Merge tag 'tty-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial patches from Greg Kroah-Hartman:
 "Here's the big tty/serial driver patches for 3.9-rc1.

  More tty port rework and fixes from Jiri here, as well as lots of
  individual serial driver updates and fixes.

  All of these have been in the linux-next tree for a while."

* tag 'tty-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (140 commits)
  tty: mxser: improve error handling in mxser_probe() and mxser_module_init()
  serial: imx: fix uninitialized variable warning
  serial: tegra: assume CONFIG_OF
  TTY: do not update atime/mtime on read/write
  lguest: select CONFIG_TTY to build properly.
  ARM defconfigs: add missing inclusions of linux/platform_device.h
  fb/exynos: include platform_device.h
  ARM: sa1100/assabet: include platform_device.h directly
  serial: imx: Fix recursive locking bug
  pps: Fix build breakage from decoupling pps from tty
  tty: Remove ancient hardpps()
  pps: Additional cleanups in uart_handle_dcd_change
  pps: Move timestamp read into PPS code proper
  pps: Don't crash the machine when exiting will do
  pps: Fix a use-after free bug when unregistering a source.
  pps: Use pps_lookup_dev to reduce ldisc coupling
  pps: Add pps_lookup_dev() function
  tty: serial: uartlite: Support uartlite on big and little endian systems
  tty: serial: uartlite: Fix sparse and checkpatch warnings
  serial/arc-uart: Miscll DT related updates (Grant's review comments)
  ...

Fix up trivial conflicts, mostly just due to the TTY config option
clashing with the EXPERIMENTAL removal.

115 files changed, 5932 insertions, 1673 deletions

diff --git a/drivers/tty/Kconfig b/drivers/tty/Kconfig
index 0ecf22b6a38..978db344bda 100644
--- a/drivers/tty/Kconfig
+++ b/drivers/tty/Kconfig
@@ -1,3 +1,14 @@
+config TTY
+	bool "Enable TTY" if EXPERT
+	default y
+	---help---
+	  Allows you to remove TTY support which can save space, and
+	  blocks features that require TTY from inclusion in the kernel.
+	  TTY is required for any text terminals or serial port
+	  communication. Most users should leave this enabled.
+
+if TTY
+
 config VT
 	bool "Virtual terminal" if EXPERT
 	depends on !S390 && !UML
@@ -388,3 +399,24 @@ config PPC_EARLY_DEBUG_EHV_BC_HANDLE
 	  If the number you specify is not a valid byte channel handle, then
 	  there simply will be no early console output.  This is true also
 	  if you don't boot under a hypervisor at all.
+
+config GOLDFISH_TTY
+	tristate "Goldfish TTY Driver"
+	depends on GOLDFISH
+	help
+	  Console and system TTY driver for the Goldfish virtual platform.
+
+config DA_TTY
+	bool "DA TTY"
+	depends on METAG_DA
+	select SERIAL_NONSTANDARD
+	help
+	  This enables a TTY on a Dash channel.
+
+config DA_CONSOLE
+	bool "DA Console"
+	depends on DA_TTY
+	help
+	  This enables a console on a Dash channel.
+
+endif # TTY
diff --git a/drivers/tty/Makefile b/drivers/tty/Makefile
index 2953059530e..6b78399bc7c 100644
--- a/drivers/tty/Makefile
+++ b/drivers/tty/Makefile
@@ -1,4 +1,4 @@
-obj-y				+= tty_io.o n_tty.o tty_ioctl.o tty_ldisc.o \
+obj-$(CONFIG_TTY)		+= tty_io.o n_tty.o tty_ioctl.o tty_ldisc.o \
 				   tty_buffer.o tty_port.o tty_mutex.o
 obj-$(CONFIG_LEGACY_PTYS)	+= pty.o
 obj-$(CONFIG_UNIX98_PTYS)	+= pty.o
@@ -27,5 +27,7 @@ obj-$(CONFIG_SYNCLINK_GT)	+= synclink_gt.o
 obj-$(CONFIG_SYNCLINKMP)	+= synclinkmp.o
 obj-$(CONFIG_SYNCLINK)		+= synclink.o
 obj-$(CONFIG_PPC_EPAPR_HV_BYTECHAN) += ehv_bytechan.o
+obj-$(CONFIG_GOLDFISH_TTY)	+= goldfish.o
+obj-$(CONFIG_DA_TTY)		+= metag_da.o
 
 obj-y += ipwireless/
diff --git a/drivers/tty/amiserial.c b/drivers/tty/amiserial.c
index 9d7d00cdfec..fc700342d43 100644
--- a/drivers/tty/amiserial.c
+++ b/drivers/tty/amiserial.c
@@ -251,7 +251,6 @@ static void receive_chars(struct serial_state *info)
 {
         int status;
 	int serdatr;
-	struct tty_struct *tty = info->tport.tty;
 	unsigned char ch, flag;
 	struct	async_icount *icount;
 	int oe = 0;
@@ -314,7 +313,7 @@ static void receive_chars(struct serial_state *info)
 #endif
 	    flag = TTY_BREAK;
 	    if (info->tport.flags & ASYNC_SAK)
-	      do_SAK(tty);
+	      do_SAK(info->tport.tty);
 	  } else if (status & UART_LSR_PE)
 	    flag = TTY_PARITY;
 	  else if (status & UART_LSR_FE)
@@ -328,10 +327,10 @@ static void receive_chars(struct serial_state *info)
 	     oe = 1;
 	  }
 	}
-	tty_insert_flip_char(tty, ch, flag);
+	tty_insert_flip_char(&info->tport, ch, flag);
 	if (oe == 1)
-		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
-	tty_flip_buffer_push(tty);
+		tty_insert_flip_char(&info->tport, 0, TTY_OVERRUN);
+	tty_flip_buffer_push(&info->tport);
 out:
 	return;
 }
@@ -394,11 +393,6 @@ static void check_modem_status(struct serial_state *info)
 			icount->dsr++;
 		if (dstatus & SER_DCD) {
 			icount->dcd++;
-#ifdef CONFIG_HARD_PPS
-			if ((port->flags & ASYNC_HARDPPS_CD) &&
-			    !(status & SER_DCD))
-				hardpps();
-#endif
 		}
 		if (dstatus & SER_CTS)
 			icount->cts++;
@@ -1099,7 +1093,7 @@ static int set_serial_info(struct tty_struct *tty, struct serial_state *state,
 	state->custom_divisor = new_serial.custom_divisor;
 	port->close_delay = new_serial.close_delay * HZ/100;
 	port->closing_wait = new_serial.closing_wait * HZ/100;
-	tty->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
+	port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 
 check_and_exit:
 	if (port->flags & ASYNC_INITIALIZED) {
@@ -1528,7 +1522,7 @@ static int rs_open(struct tty_struct *tty, struct file * filp)
 	if (serial_paranoia_check(info, tty->name, "rs_open"))
 		return -ENODEV;
 
-	tty->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
+	port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 
 	retval = startup(tty, info);
 	if (retval) {
diff --git a/drivers/tty/bfin_jtag_comm.c b/drivers/tty/bfin_jtag_comm.c
index 1cfcdbf1d0c..a93a424873f 100644
--- a/drivers/tty/bfin_jtag_comm.c
+++ b/drivers/tty/bfin_jtag_comm.c
@@ -95,18 +95,16 @@ bfin_jc_emudat_manager(void *arg)
 
 		/* if incoming data is ready, eat it */
 		if (bfin_read_DBGSTAT() & EMUDIF) {
-			if (tty != NULL) {
-				uint32_t emudat = bfin_read_emudat();
-				if (inbound_len == 0) {
-					pr_debug("incoming length: 0x%08x\n", emudat);
-					inbound_len = emudat;
-				} else {
-					size_t num_chars = (4 <= inbound_len ? 4 : inbound_len);
-					pr_debug("  incoming data: 0x%08x (pushing %zu)\n", emudat, num_chars);
-					inbound_len -= num_chars;
-					tty_insert_flip_string(tty, (unsigned char *)&emudat, num_chars);
-					tty_flip_buffer_push(tty);
-				}
+			uint32_t emudat = bfin_read_emudat();
+			if (inbound_len == 0) {
+				pr_debug("incoming length: 0x%08x\n", emudat);
+				inbound_len = emudat;
+			} else {
+				size_t num_chars = (4 <= inbound_len ? 4 : inbound_len);
+				pr_debug("  incoming data: 0x%08x (pushing %zu)\n", emudat, num_chars);
+				inbound_len -= num_chars;
+				tty_insert_flip_string(&port, (unsigned char *)&emudat, num_chars);
+				tty_flip_buffer_push(&port);
 			}
 		}
 
diff --git a/drivers/tty/cyclades.c b/drivers/tty/cyclades.c
index b09c8d1f9a6..345bd0e0884 100644
--- a/drivers/tty/cyclades.c
+++ b/drivers/tty/cyclades.c
@@ -441,7 +441,7 @@ static void cyy_chip_rx(struct cyclades_card *cinfo, int chip,
 		void __iomem *base_addr)
 {
 	struct cyclades_port *info;
-	struct tty_struct *tty;
+	struct tty_port *port;
 	int len, index = cinfo->bus_index;
 	u8 ivr, save_xir, channel, save_car, data, char_count;
 
@@ -452,22 +452,11 @@ static void cyy_chip_rx(struct cyclades_card *cinfo, int chip,
 	save_xir = readb(base_addr + (CyRIR << index));
 	channel = save_xir & CyIRChannel;
 	info = &cinfo->ports[channel + chip * 4];
+	port = &info->port;
 	save_car = cyy_readb(info, CyCAR);
 	cyy_writeb(info, CyCAR, save_xir);
 	ivr = cyy_readb(info, CyRIVR) & CyIVRMask;
 
-	tty = tty_port_tty_get(&info->port);
-	/* if there is nowhere to put the data, discard it */
-	if (tty == NULL) {
-		if (ivr == CyIVRRxEx) {	/* exception */
-			data = cyy_readb(info, CyRDSR);
-		} else {	/* normal character reception */
-			char_count = cyy_readb(info, CyRDCR);
-			while (char_count--)
-				data = cyy_readb(info, CyRDSR);
-		}
-		goto end;
-	}
 	/* there is an open port for this data */
 	if (ivr == CyIVRRxEx) {	/* exception */
 		data = cyy_readb(info, CyRDSR);
@@ -484,40 +473,45 @@ static void cyy_chip_rx(struct cyclades_card *cinfo, int chip,
 
 		if (data & info->ignore_status_mask) {
 			info->icount.rx++;
-			tty_kref_put(tty);
 			return;
 		}
-		if (tty_buffer_request_room(tty, 1)) {
+		if (tty_buffer_request_room(port, 1)) {
 			if (data & info->read_status_mask) {
 				if (data & CyBREAK) {
-					tty_insert_flip_char(tty,
+					tty_insert_flip_char(port,
 						cyy_readb(info, CyRDSR),
 						TTY_BREAK);
 					info->icount.rx++;
-					if (info->port.flags & ASYNC_SAK)
-						do_SAK(tty);
+					if (port->flags & ASYNC_SAK) {
+						struct tty_struct *tty =
+							tty_port_tty_get(port);
+						if (tty) {
+							do_SAK(tty);
+							tty_kref_put(tty);
+						}
+					}
 				} else if (data & CyFRAME) {
-					tty_insert_flip_char(tty,
+					tty_insert_flip_char(port,
 						cyy_readb(info, CyRDSR),
 						TTY_FRAME);
 					info->icount.rx++;
 					info->idle_stats.frame_errs++;
 				} else if (data & CyPARITY) {
 					/* Pieces of seven... */
-					tty_insert_flip_char(tty,
+					tty_insert_flip_char(port,
 						cyy_readb(info, CyRDSR),
 						TTY_PARITY);
 					info->icount.rx++;
 					info->idle_stats.parity_errs++;
 				} else if (data & CyOVERRUN) {
-					tty_insert_flip_char(tty, 0,
+					tty_insert_flip_char(port, 0,
 							TTY_OVERRUN);
 					info->icount.rx++;
 					/* If the flip buffer itself is
 					   overflowing, we still lose
 					   the next incoming character.
 					 */
-					tty_insert_flip_char(tty,
+					tty_insert_flip_char(port,
 						cyy_readb(info, CyRDSR),
 						TTY_FRAME);
 					info->icount.rx++;
@@ -527,12 +521,12 @@ static void cyy_chip_rx(struct cyclades_card *cinfo, int chip,
 				/* } else if(data & CyTIMEOUT) { */
 				/* } else if(data & CySPECHAR) { */
 				} else {
-					tty_insert_flip_char(tty, 0,
+					tty_insert_flip_char(port, 0,
 							TTY_NORMAL);
 					info->icount.rx++;
 				}
 			} else {
-				tty_insert_flip_char(tty, 0, TTY_NORMAL);
+				tty_insert_flip_char(port, 0, TTY_NORMAL);
 				info->icount.rx++;
 			}
 		} else {
@@ -552,10 +546,10 @@ static void cyy_chip_rx(struct cyclades_card *cinfo, int chip,
 			info->mon.char_max = char_count;
 		info->mon.char_last = char_count;
 #endif
-		len = tty_buffer_request_room(tty, char_count);
+		len = tty_buffer_request_room(port, char_count);
 		while (len--) {
 			data = cyy_readb(info, CyRDSR);
-			tty_insert_flip_char(tty, data, TTY_NORMAL);
+			tty_insert_flip_char(port, data, TTY_NORMAL);
 			info->idle_stats.recv_bytes++;
 			info->icount.rx++;
 #ifdef CY_16Y_HACK
@@ -564,9 +558,8 @@ static void cyy_chip_rx(struct cyclades_card *cinfo, int chip,
 		}
 		info->idle_stats.recv_idle = jiffies;
 	}
-	tty_schedule_flip(tty);
-	tty_kref_put(tty);
-end:
+	tty_schedule_flip(port);
+
 	/* end of service */
 	cyy_writeb(info, CyRIR, save_xir & 0x3f);
 	cyy_writeb(info, CyCAR, save_car);
@@ -924,10 +917,11 @@ cyz_issue_cmd(struct cyclades_card *cinfo,
 	return 0;
 }				/* cyz_issue_cmd */
 
-static void cyz_handle_rx(struct cyclades_port *info, struct tty_struct *tty)
+static void cyz_handle_rx(struct cyclades_port *info)
 {
 	struct BUF_CTRL __iomem *buf_ctrl = info->u.cyz.buf_ctrl;
 	struct cyclades_card *cinfo = info->card;
+	struct tty_port *port = &info->port;
 	unsigned int char_count;
 	int len;
 #ifdef BLOCKMOVE
@@ -946,80 +940,77 @@ static void cyz_handle_rx(struct cyclades_port *info, struct tty_struct *tty)
 	else
 		char_count = rx_put - rx_get + rx_bufsize;
 
-	if (char_count) {
+	if (!char_count)
+		return;
+
 #ifdef CY_ENABLE_MONITORING
-		info->mon.int_count++;
-		info->mon.char_count += char_count;
-		if (char_count > info->mon.char_max)
-			info->mon.char_max = char_count;
-		info->mon.char_last = char_count;
+	info->mon.int_count++;
+	info->mon.char_count += char_count;
+	if (char_count > info->mon.char_max)
+		info->mon.char_max = char_count;
+	info->mon.char_last = char_count;
 #endif
-		if (tty == NULL) {
-			/* flush received characters */
-			new_rx_get = (new_rx_get + char_count) &
-					(rx_bufsize - 1);
-			info->rflush_count++;
-		} else {
+
 #ifdef BLOCKMOVE
-		/* we'd like to use memcpy(t, f, n) and memset(s, c, count)
-		   for performance, but because of buffer boundaries, there
-		   may be several steps to the operation */
-			while (1) {
-				len = tty_prepare_flip_string(tty, &buf,
-						char_count);
-				if (!len)
-					break;
+	/* we'd like to use memcpy(t, f, n) and memset(s, c, count)
+	   for performance, but because of buffer boundaries, there
+	   may be several steps to the operation */
+	while (1) {
+		len = tty_prepare_flip_string(port, &buf,
+				char_count);
+		if (!len)
+			break;
 
-				len = min_t(unsigned int, min(len, char_count),
-						rx_bufsize - new_rx_get);
+		len = min_t(unsigned int, min(len, char_count),
+				rx_bufsize - new_rx_get);
 
-				memcpy_fromio(buf, cinfo->base_addr +
-						rx_bufaddr + new_rx_get, len);
+		memcpy_fromio(buf, cinfo->base_addr +
+				rx_bufaddr + new_rx_get, len);
 
-				new_rx_get = (new_rx_get + len) &
-						(rx_bufsize - 1);
-				char_count -= len;
-				info->icount.rx += len;
-				info->idle_stats.recv_bytes += len;
-			}
+		new_rx_get = (new_rx_get + len) &
+				(rx_bufsize - 1);
+		char_count -= len;
+		info->icount.rx += len;
+		info->idle_stats.recv_bytes += len;
+	}
 #else
-			len = tty_buffer_request_room(tty, char_count);
-			while (len--) {
-				data = readb(cinfo->base_addr + rx_bufaddr +
-						new_rx_get);
-				new_rx_get = (new_rx_get + 1) &
-							(rx_bufsize - 1);
-				tty_insert_flip_char(tty, data, TTY_NORMAL);
-				info->idle_stats.recv_bytes++;
-				info->icount.rx++;
-			}
+	len = tty_buffer_request_room(port, char_count);
+	while (len--) {
+		data = readb(cinfo->base_addr + rx_bufaddr +
+				new_rx_get);
+		new_rx_get = (new_rx_get + 1) &
+					(rx_bufsize - 1);
+		tty_insert_flip_char(port, data, TTY_NORMAL);
+		info->idle_stats.recv_bytes++;
+		info->icount.rx++;
+	}
 #endif
 #ifdef CONFIG_CYZ_INTR
-		/* Recalculate the number of chars in the RX buffer and issue
-		   a cmd in case it's higher than the RX high water mark */
-			rx_put = readl(&buf_ctrl->rx_put);
-			if (rx_put >= rx_get)
-				char_count = rx_put - rx_get;
-			else
-				char_count = rx_put - rx_get + rx_bufsize;
-			if (char_count >= readl(&buf_ctrl->rx_threshold) &&
-					!timer_pending(&cyz_rx_full_timer[
-							info->line]))
-				mod_timer(&cyz_rx_full_timer[info->line],
-						jiffies + 1);
+	/* Recalculate the number of chars in the RX buffer and issue
+	   a cmd in case it's higher than the RX high water mark */
+	rx_put = readl(&buf_ctrl->rx_put);
+	if (rx_put >= rx_get)
+		char_count = rx_put - rx_get;
+	else
+		char_count = rx_put - rx_get + rx_bufsize;
+	if (char_count >= readl(&buf_ctrl->rx_threshold) &&
+			!timer_pending(&cyz_rx_full_timer[
+					info->line]))
+		mod_timer(&cyz_rx_full_timer[info->line],
+				jiffies + 1);
 #endif
-			info->idle_stats.recv_idle = jiffies;
-			tty_schedule_flip(tty);
-		}
-		/* Update rx_get */
-		cy_writel(&buf_ctrl->rx_get, new_rx_get);
-	}
+	info->idle_stats.recv_idle = jiffies;
+	tty_schedule_flip(&info->port);
+
+	/* Update rx_get */
+	cy_writel(&buf_ctrl->rx_get, new_rx_get);
 }
 
-static void cyz_handle_tx(struct cyclades_port *info, struct tty_struct *tty)
+static void cyz_handle_tx(struct cyclades_port *info)
 {
 	struct BUF_CTRL __iomem *buf_ctrl = info->u.cyz.buf_ctrl;
 	struct cyclades_card *cinfo = info->card;
+	struct tty_struct *tty;
 	u8 data;
 	unsigned int char_count;
 #ifdef BLOCKMOVE
@@ -1039,63 +1030,63 @@ static void cyz_handle_tx(struct cyclades_port *info, struct tty_struct *tty)
 	else
 		char_count = tx_get - tx_put - 1;
 
-	if (char_count) {
-
-		if (tty == NULL)
-			goto ztxdone;
+	if (!char_count)
+		return;
+		
+	tty = tty_port_tty_get(&info->port);
+	if (tty == NULL)
+		goto ztxdone;
 
-		if (info->x_char) {	/* send special char */
-			data = info->x_char;
+	if (info->x_char) {	/* send special char */
+		data = info->x_char;
 
-			cy_writeb(cinfo->base_addr + tx_bufaddr + tx_put, data);
-			tx_put = (tx_put + 1) & (tx_bufsize - 1);
-			info->x_char = 0;
-			char_count--;
-			info->icount.tx++;
-		}
+		cy_writeb(cinfo->base_addr + tx_bufaddr + tx_put, data);
+		tx_put = (tx_put + 1) & (tx_bufsize - 1);
+		info->x_char = 0;
+		char_count--;
+		info->icount.tx++;
+	}
 #ifdef BLOCKMOVE
-		while (0 < (small_count = min_t(unsigned int,
-				tx_bufsize - tx_put, min_t(unsigned int,
-					(SERIAL_XMIT_SIZE - info->xmit_tail),
-					min_t(unsigned int, info->xmit_cnt,
-						char_count))))) {
-
-			memcpy_toio((char *)(cinfo->base_addr + tx_bufaddr +
-					tx_put),
-					&info->port.xmit_buf[info->xmit_tail],
-					small_count);
-
-			tx_put = (tx_put + small_count) & (tx_bufsize - 1);
-			char_count -= small_count;
-			info->icount.tx += small_count;
-			info->xmit_cnt -= small_count;
-			info->xmit_tail = (info->xmit_tail + small_count) &
-					(SERIAL_XMIT_SIZE - 1);
-		}
+	while (0 < (small_count = min_t(unsigned int,
+			tx_bufsize - tx_put, min_t(unsigned int,
+				(SERIAL_XMIT_SIZE - info->xmit_tail),
+				min_t(unsigned int, info->xmit_cnt,
+					char_count))))) {
+
+		memcpy_toio((char *)(cinfo->base_addr + tx_bufaddr + tx_put),
+				&info->port.xmit_buf[info->xmit_tail],
+				small_count);
+
+		tx_put = (tx_put + small_count) & (tx_bufsize - 1);
+		char_count -= small_count;
+		info->icount.tx += small_count;
+		info->xmit_cnt -= small_count;
+		info->xmit_tail = (info->xmit_tail + small_count) &
+				(SERIAL_XMIT_SIZE - 1);
+	}
 #else
-		while (info->xmit_cnt && char_count) {
-			data = info->port.xmit_buf[info->xmit_tail];
-			info->xmit_cnt--;
-			info->xmit_tail = (info->xmit_tail + 1) &
-					(SERIAL_XMIT_SIZE - 1);
-
-			cy_writeb(cinfo->base_addr + tx_bufaddr + tx_put, data);
-			tx_put = (tx_put + 1) & (tx_bufsize - 1);
-			char_count--;
-			info->icount.tx++;
-		}
+	while (info->xmit_cnt && char_count) {
+		data = info->port.xmit_buf[info->xmit_tail];
+		info->xmit_cnt--;
+		info->xmit_tail = (info->xmit_tail + 1) &
+				(SERIAL_XMIT_SIZE - 1);
+
+		cy_writeb(cinfo->base_addr + tx_bufaddr + tx_put, data);
+		tx_put = (tx_put + 1) & (tx_bufsize - 1);
+		char_count--;
+		info->icount.tx++;
+	}
 #endif
-		tty_wakeup(tty);
+	tty_wakeup(tty);
+	tty_kref_put(tty);
 ztxdone:
-		/* Update tx_put */
-		cy_writel(&buf_ctrl->tx_put, tx_put);
-	}
+	/* Update tx_put */
+	cy_writel(&buf_ctrl->tx_put, tx_put);
 }
 
 static void cyz_handle_cmd(struct cyclades_card *cinfo)
 {
 	struct BOARD_CTRL __iomem *board_ctrl = cinfo->board_ctrl;
-	struct tty_struct *tty;
 	struct cyclades_port *info;
 	__u32 channel, param, fw_ver;
 	__u8 cmd;
@@ -1108,23 +1099,20 @@ static void cyz_handle_cmd(struct cyclades_card *cinfo)
 		special_count = 0;
 		delta_count = 0;
 		info = &cinfo->ports[channel];
-		tty = tty_port_tty_get(&info->port);
-		if (tty == NULL)
-			continue;
 
 		switch (cmd) {
 		case C_CM_PR_ERROR:
-			tty_insert_flip_char(tty, 0, TTY_PARITY);
+			tty_insert_flip_char(&info->port, 0, TTY_PARITY);
 			info->icount.rx++;
 			special_count++;
 			break;
 		case C_CM_FR_ERROR:
-			tty_insert_flip_char(tty, 0, TTY_FRAME);
+			tty_insert_flip_char(&info->port, 0, TTY_FRAME);
 			info->icount.rx++;
 			special_count++;
 			break;
 		case C_CM_RXBRK:
-			tty_insert_flip_char(tty, 0, TTY_BREAK);
+			tty_insert_flip_char(&info->port, 0, TTY_BREAK);
 			info->icount.rx++;
 			special_count++;
 			break;
@@ -1136,8 +1124,14 @@ static void cyz_handle_cmd(struct cyclades_card *cinfo)
 					readl(&info->u.cyz.ch_ctrl->rs_status);
 				if (dcd & C_RS_DCD)
 					wake_up_interruptible(&info->port.open_wait);
-				else
-					tty_hangup(tty);
+				else {
+					struct tty_struct *tty;
+					tty = tty_port_tty_get(&info->port);
+					if (tty) {
+						tty_hangup(tty);
+						tty_kref_put(tty);
+					}
+				}
 			}
 			break;
 		case C_CM_MCTS:
@@ -1166,7 +1160,7 @@ static void cyz_handle_cmd(struct cyclades_card *cinfo)
 			printk(KERN_DEBUG "cyz_interrupt: rcvd intr, card %d, "
 					"port %ld\n", info->card, channel);
 #endif
-			cyz_handle_rx(info, tty);
+			cyz_handle_rx(info);
 			break;
 		case C_CM_TXBEMPTY:
 		case C_CM_TXLOWWM:
@@ -1176,7 +1170,7 @@ static void cyz_handle_cmd(struct cyclades_card *cinfo)
 			printk(KERN_DEBUG "cyz_interrupt: xmit intr, card %d, "
 					"port %ld\n", info->card, channel);
 #endif
-			cyz_handle_tx(info, tty);
+			cyz_handle_tx(info);
 			break;
 #endif				/* CONFIG_CYZ_INTR */
 		case C_CM_FATAL:
@@ -1188,8 +1182,7 @@ static void cyz_handle_cmd(struct cyclades_card *cinfo)
 		if (delta_count)
 			wake_up_interruptible(&info->port.delta_msr_wait);
 		if (special_count)
-			tty_schedule_flip(tty);
-		tty_kref_put(tty);
+			tty_schedule_flip(&info->port);
 	}
 }
 
@@ -1255,17 +1248,11 @@ static void cyz_poll(unsigned long arg)
 		cyz_handle_cmd(cinfo);
 
 		for (port = 0; port < cinfo->nports; port++) {
-			struct tty_struct *tty;
-
 			info = &cinfo->ports[port];
-			tty = tty_port_tty_get(&info->port);
-			/* OK to pass NULL to the handle functions below.
-			   They need to drop the data in that case. */
 
 			if (!info->throttle)
-				cyz_handle_rx(info, tty);
-			cyz_handle_tx(info, tty);
-			tty_kref_put(tty);
+				cyz_handle_rx(info);
+			cyz_handle_tx(info);
 		}
 		/* poll every 'cyz_polling_cycle' period */
 		expires = jiffies + cyz_polling_cycle;
diff --git a/drivers/tty/ehv_bytechan.c b/drivers/tty/ehv_bytechan.c
index c117d775a22..ed92622b894 100644
--- a/drivers/tty/ehv_bytechan.c
+++ b/drivers/tty/ehv_bytechan.c
@@ -371,22 +371,17 @@ console_initcall(ehv_bc_console_init);
 static irqreturn_t ehv_bc_tty_rx_isr(int irq, void *data)
 {
 	struct ehv_bc_data *bc = data;
-	struct tty_struct *ttys = tty_port_tty_get(&bc->port);
 	unsigned int rx_count, tx_count, len;
 	int count;
 	char buffer[EV_BYTE_CHANNEL_MAX_BYTES];
 	int ret;
 
-	/* ttys could be NULL during a hangup */
-	if (!ttys)
-		return IRQ_HANDLED;
-
 	/* Find out how much data needs to be read, and then ask the TTY layer
 	 * if it can handle that much.  We want to ensure that every byte we
 	 * read from the byte channel will be accepted by the TTY layer.
 	 */
 	ev_byte_channel_poll(bc->handle, &rx_count, &tx_count);
-	count = tty_buffer_request_room(ttys, rx_count);
+	count = tty_buffer_request_room(&bc->port, rx_count);
 
 	/* 'count' is the maximum amount of data the TTY layer can accept at
 	 * this time.  However, during testing, I was never able to get 'count'
@@ -407,7 +402,7 @@ static irqreturn_t ehv_bc_tty_rx_isr(int irq, void *data)
 		 */
 
 		/* Pass the received data to the tty layer. */
-		ret = tty_insert_flip_string(ttys, buffer, len);
+		ret = tty_insert_flip_string(&bc->port, buffer, len);
 
 		/* 'ret' is the number of bytes that the TTY layer accepted.
 		 * If it's not equal to 'len', then it means the buffer is
@@ -422,9 +417,7 @@ static irqreturn_t ehv_bc_tty_rx_isr(int irq, void *data)
 	}
 
 	/* Tell the tty layer that we're done. */
-	tty_flip_buffer_push(ttys);
-
-	tty_kref_put(ttys);
+	tty_flip_buffer_push(&bc->port);
 
 	return IRQ_HANDLED;
 }
diff --git a/drivers/tty/goldfish.c b/drivers/tty/goldfish.c
new file mode 100644
index 00000000000..f17d2e4ee2c
--- /dev/null
+++ b/drivers/tty/goldfish.c
@@ -0,0 +1,328 @@
+/*
+ * Copyright (C) 2007 Google, Inc.
+ * Copyright (C) 2012 Intel, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/console.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/module.h>
+
+enum {
+	GOLDFISH_TTY_PUT_CHAR       = 0x00,
+	GOLDFISH_TTY_BYTES_READY    = 0x04,
+	GOLDFISH_TTY_CMD            = 0x08,
+
+	GOLDFISH_TTY_DATA_PTR       = 0x10,
+	GOLDFISH_TTY_DATA_LEN       = 0x14,
+
+	GOLDFISH_TTY_CMD_INT_DISABLE    = 0,
+	GOLDFISH_TTY_CMD_INT_ENABLE     = 1,
+	GOLDFISH_TTY_CMD_WRITE_BUFFER   = 2,
+	GOLDFISH_TTY_CMD_READ_BUFFER    = 3,
+};
+
+struct goldfish_tty {
+	struct tty_port port;
+	spinlock_t lock;
+	void __iomem *base;
+	u32 irq;
+	int opencount;
+	struct console console;
+};
+
+static DEFINE_MUTEX(goldfish_tty_lock);
+static struct tty_driver *goldfish_tty_driver;
+static u32 goldfish_tty_line_count = 8;
+static u32 goldfish_tty_current_line_count;
+static struct goldfish_tty *goldfish_ttys;
+
+static void goldfish_tty_do_write(int line, const char *buf, unsigned count)
+{
+	unsigned long irq_flags;
+	struct goldfish_tty *qtty = &goldfish_ttys[line];
+	void __iomem *base = qtty->base;
+	spin_lock_irqsave(&qtty->lock, irq_flags);
+	writel((u32)buf, base + GOLDFISH_TTY_DATA_PTR);
+	writel(count, base + GOLDFISH_TTY_DATA_LEN);
+	writel(GOLDFISH_TTY_CMD_WRITE_BUFFER, base + GOLDFISH_TTY_CMD);
+	spin_unlock_irqrestore(&qtty->lock, irq_flags);
+}
+
+static irqreturn_t goldfish_tty_interrupt(int irq, void *dev_id)
+{
+	struct platform_device *pdev = dev_id;
+	struct goldfish_tty *qtty = &goldfish_ttys[pdev->id];
+	void __iomem *base = qtty->base;
+	unsigned long irq_flags;
+	unsigned char *buf;
+	u32 count;
+
+	count = readl(base + GOLDFISH_TTY_BYTES_READY);
+	if(count == 0)
+		return IRQ_NONE;
+
+	count = tty_prepare_flip_string(&qtty->port, &buf, count);
+	spin_lock_irqsave(&qtty->lock, irq_flags);
+	writel((u32)buf, base + GOLDFISH_TTY_DATA_PTR);
+	writel(count, base + GOLDFISH_TTY_DATA_LEN);
+	writel(GOLDFISH_TTY_CMD_READ_BUFFER, base + GOLDFISH_TTY_CMD);
+	spin_unlock_irqrestore(&qtty->lock, irq_flags);
+	tty_schedule_flip(&qtty->port);
+	return IRQ_HANDLED;
+}
+
+static int goldfish_tty_activate(struct tty_port *port, struct tty_struct *tty)
+{
+	struct goldfish_tty *qtty = container_of(port, struct goldfish_tty, port);
+	writel(GOLDFISH_TTY_CMD_INT_ENABLE, qtty->base + GOLDFISH_TTY_CMD);
+	return 0;
+}
+
+static void goldfish_tty_shutdown(struct tty_port *port)
+{
+	struct goldfish_tty *qtty = container_of(port, struct goldfish_tty, port);
+	writel(GOLDFISH_TTY_CMD_INT_DISABLE, qtty->base + GOLDFISH_TTY_CMD);
+}
+
+static int goldfish_tty_open(struct tty_struct * tty, struct file * filp)
+{
+	struct goldfish_tty *qtty = &goldfish_ttys[tty->index];
+	return tty_port_open(&qtty->port, tty, filp);
+}
+
+static void goldfish_tty_close(struct tty_struct * tty, struct file * filp)
+{
+	tty_port_close(tty->port, tty, filp);
+}
+
+static void goldfish_tty_hangup(struct tty_struct *tty)
+{
+	tty_port_hangup(tty->port);
+}
+
+static int goldfish_tty_write(struct tty_struct * tty, const unsigned char *buf, int count)
+{
+	goldfish_tty_do_write(tty->index, buf, count);
+	return count;
+}
+
+static int goldfish_tty_write_room(struct tty_struct *tty)
+{
+	return 0x10000;
+}
+
+static int goldfish_tty_chars_in_buffer(struct tty_struct *tty)
+{
+	struct goldfish_tty *qtty = &goldfish_ttys[tty->index];
+	void __iomem *base = qtty->base;
+	return readl(base + GOLDFISH_TTY_BYTES_READY);
+}
+
+static void goldfish_tty_console_write(struct console *co, const char *b, unsigned count)
+{
+	goldfish_tty_do_write(co->index, b, count);
+}
+
+static struct tty_driver *goldfish_tty_console_device(struct console *c, int *index)
+{
+	*index = c->index;
+	return goldfish_tty_driver;
+}
+
+static int goldfish_tty_console_setup(struct console *co, char *options)
+{
+	if((unsigned)co->index > goldfish_tty_line_count)
+		return -ENODEV;
+	if(goldfish_ttys[co->index].base == 0)
+		return -ENODEV;
+	return 0;
+}
+
+static struct tty_port_operations goldfish_port_ops = {
+	.activate = goldfish_tty_activate,
+	.shutdown = goldfish_tty_shutdown
+};
+
+static struct tty_operations goldfish_tty_ops = {
+	.open = goldfish_tty_open,
+	.close = goldfish_tty_close,
+	.hangup = goldfish_tty_hangup,
+	.write = goldfish_tty_write,
+	.write_room = goldfish_tty_write_room,
+	.chars_in_buffer = goldfish_tty_chars_in_buffer,
+};
+
+static int goldfish_tty_create_driver(void)
+{
+	int ret;
+	struct tty_driver *tty;
+
+	goldfish_ttys = kzalloc(sizeof(*goldfish_ttys) * goldfish_tty_line_count, GFP_KERNEL);
+	if(goldfish_ttys == NULL) {
+		ret = -ENOMEM;
+		goto err_alloc_goldfish_ttys_failed;
+	}
+	tty = alloc_tty_driver(goldfish_tty_line_count);
+	if(tty == NULL) {
+		ret = -ENOMEM;
+		goto err_alloc_tty_driver_failed;
+	}
+	tty->driver_name = "goldfish";
+	tty->name = "ttyGF";
+	tty->type = TTY_DRIVER_TYPE_SERIAL;
+	tty->subtype = SERIAL_TYPE_NORMAL;
+	tty->init_termios = tty_std_termios;
+	tty->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
+	tty_set_operations(tty, &goldfish_tty_ops);
+	ret = tty_register_driver(tty);
+	if(ret)
+		goto err_tty_register_driver_failed;
+
+	goldfish_tty_driver = tty;
+	return 0;
+
+err_tty_register_driver_failed:
+	put_tty_driver(tty);
+err_alloc_tty_driver_failed:
+	kfree(goldfish_ttys);
+	goldfish_ttys = NULL;
+err_alloc_goldfish_ttys_failed:
+	return ret;
+}
+
+static void goldfish_tty_delete_driver(void)
+{
+	tty_unregister_driver(goldfish_tty_driver);
+	put_tty_driver(goldfish_tty_driver);
+	goldfish_tty_driver = NULL;
+	kfree(goldfish_ttys);
+	goldfish_ttys = NULL;
+}
+
+static int goldfish_tty_probe(struct platform_device *pdev)
+{
+	struct goldfish_tty *qtty;
+	int ret = -EINVAL;
+	int i;
+	struct resource *r;
+	struct device *ttydev;
+	void __iomem *base;
+	u32 irq;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if(r == NULL)
+		return -EINVAL;
+
+	base = ioremap(r->start, 0x1000);
+	if (base == NULL)
+		pr_err("goldfish_tty: unable to remap base\n");
+
+	r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if(r == NULL)
+		goto err_unmap;
+
+	irq = r->start;
+
+	if(pdev->id >= goldfish_tty_line_count)
+		goto err_unmap;
+
+	mutex_lock(&goldfish_tty_lock);
+	if(goldfish_tty_current_line_count == 0) {
+		ret = goldfish_tty_create_driver();
+		if(ret)
+			goto err_create_driver_failed;
+	}
+	goldfish_tty_current_line_count++;
+
+	qtty = &goldfish_ttys[pdev->id];
+	spin_lock_init(&qtty->lock);
+	tty_port_init(&qtty->port);
+	qtty->port.ops = &goldfish_port_ops;
+	qtty->base = base;
+	qtty->irq = irq;
+
+	writel(GOLDFISH_TTY_CMD_INT_DISABLE, base + GOLDFISH_TTY_CMD);
+
+	ret = request_irq(irq, goldfish_tty_interrupt, IRQF_SHARED, "goldfish_tty", pdev);
+	if(ret)
+		goto err_request_irq_failed;
+
+
+	ttydev = tty_port_register_device(&qtty->port, goldfish_tty_driver,
+							pdev->id, &pdev->dev);
+	if(IS_ERR(ttydev)) {
+		ret = PTR_ERR(ttydev);
+		goto err_tty_register_device_failed;
+	}
+
+	strcpy(qtty->console.name, "ttyGF");
+	qtty->console.write = goldfish_tty_console_write;
+	qtty->console.device = goldfish_tty_console_device;
+	qtty->console.setup = goldfish_tty_console_setup;
+	qtty->console.flags = CON_PRINTBUFFER;
+	qtty->console.index = pdev->id;
+	register_console(&qtty->console);
+
+	mutex_unlock(&goldfish_tty_lock);
+	return 0;
+
+	tty_unregister_device(goldfish_tty_driver, i);
+err_tty_register_device_failed:
+	free_irq(irq, pdev);
+err_request_irq_failed:
+	goldfish_tty_current_line_count--;
+	if(goldfish_tty_current_line_count == 0)
+		goldfish_tty_delete_driver();
+err_create_driver_failed:
+	mutex_unlock(&goldfish_tty_lock);
+err_unmap:
+	iounmap(base);
+	return ret;
+}
+
+static int goldfish_tty_remove(struct platform_device *pdev)
+{
+	struct goldfish_tty *qtty;
+
+	mutex_lock(&goldfish_tty_lock);
+
+	qtty = &goldfish_ttys[pdev->id];
+	unregister_console(&qtty->console);
+	tty_unregister_device(goldfish_tty_driver, pdev->id);
+	iounmap(qtty->base);
+	qtty->base = 0;
+	free_irq(qtty->irq, pdev);
+	goldfish_tty_current_line_count--;
+	if(goldfish_tty_current_line_count == 0)
+		goldfish_tty_delete_driver();
+	mutex_unlock(&goldfish_tty_lock);
+	return 0;
+}
+
+static struct platform_driver goldfish_tty_platform_driver = {
+	.probe = goldfish_tty_probe,
+	.remove = goldfish_tty_remove,
+	.driver = {
+		.name = "goldfish_tty"
+	}
+};
+
+module_platform_driver(goldfish_tty_platform_driver);
+
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/tty/hvc/Kconfig b/drivers/tty/hvc/Kconfig
index f47b734c6a7..8902f9b4df7 100644
--- a/drivers/tty/hvc/Kconfig
+++ b/drivers/tty/hvc/Kconfig
@@ -1,3 +1,5 @@
+if TTY
+
 config HVC_DRIVER
 	bool
 	help
@@ -119,3 +121,4 @@ config HVCS
 	  which will also be compiled when this driver is built as a
 	  module.
 
+endif # TTY
diff --git a/drivers/tty/hvc/hvc_console.c b/drivers/tty/hvc/hvc_console.c
index 13ee53bd0bf..eb255e807c0 100644
--- a/drivers/tty/hvc/hvc_console.c
+++ b/drivers/tty/hvc/hvc_console.c
@@ -629,7 +629,7 @@ int hvc_poll(struct hvc_struct *hp)
 
 	/* Read data if any */
 	for (;;) {
-		int count = tty_buffer_request_room(tty, N_INBUF);
+		int count = tty_buffer_request_room(&hp->port, N_INBUF);
 
 		/* If flip is full, just reschedule a later read */
 		if (count == 0) {
@@ -672,7 +672,7 @@ int hvc_poll(struct hvc_struct *hp)
 				}
 			}
 #endif /* CONFIG_MAGIC_SYSRQ */
-			tty_insert_flip_char(tty, buf[i], 0);
+			tty_insert_flip_char(&hp->port, buf[i], 0);
 		}
 
 		read_total += n;
@@ -691,7 +691,7 @@ int hvc_poll(struct hvc_struct *hp)
 		   a minimum for performance. */
 		timeout = MIN_TIMEOUT;
 
-		tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(&hp->port);
 	}
 	tty_kref_put(tty);
 
diff --git a/drivers/tty/hvc/hvcs.c b/drivers/tty/hvc/hvcs.c
index 87763573395..1956593ee89 100644
--- a/drivers/tty/hvc/hvcs.c
+++ b/drivers/tty/hvc/hvcs.c
@@ -609,11 +609,11 @@ static int hvcs_io(struct hvcs_struct *hvcsd)
 	/* remove the read masks */
 	hvcsd->todo_mask &= ~(HVCS_READ_MASK);
 
-	if (tty_buffer_request_room(tty, HVCS_BUFF_LEN) >= HVCS_BUFF_LEN) {
+	if (tty_buffer_request_room(&hvcsd->port, HVCS_BUFF_LEN) >= HVCS_BUFF_LEN) {
 		got = hvc_get_chars(unit_address,
 				&buf[0],
 				HVCS_BUFF_LEN);
-		tty_insert_flip_string(tty, buf, got);
+		tty_insert_flip_string(&hvcsd->port, buf, got);
 	}
 
 	/* Give the TTY time to process the data we just sent. */
@@ -623,7 +623,7 @@ static int hvcs_io(struct hvcs_struct *hvcsd)
 	spin_unlock_irqrestore(&hvcsd->lock, flags);
 	/* This is synch because tty->low_latency == 1 */
 	if(got)
-		tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(&hvcsd->port);
 
 	if (!got) {
 		/* Do this _after_ the flip_buffer_push */
diff --git a/drivers/tty/hvc/hvsi.c b/drivers/tty/hvc/hvsi.c
index 68357a6e4de..ef95a154854 100644
--- a/drivers/tty/hvc/hvsi.c
+++ b/drivers/tty/hvc/hvsi.c
@@ -329,8 +329,7 @@ static void hvsi_recv_query(struct hvsi_struct *hp, uint8_t *packet)
 	}
 }
 
-static void hvsi_insert_chars(struct hvsi_struct *hp, struct tty_struct *tty,
-		const char *buf, int len)
+static void hvsi_insert_chars(struct hvsi_struct *hp, const char *buf, int len)
 {
 	int i;
 
@@ -346,7 +345,7 @@ static void hvsi_insert_chars(struct hvsi_struct *hp, struct tty_struct *tty,
 			continue;
 		}
 #endif /* CONFIG_MAGIC_SYSRQ */
-		tty_insert_flip_char(tty, c, 0);
+		tty_insert_flip_char(&hp->port, c, 0);
 	}
 }
 
@@ -359,8 +358,7 @@ static void hvsi_insert_chars(struct hvsi_struct *hp, struct tty_struct *tty,
  * revisited.
  */
 #define TTY_THRESHOLD_THROTTLE 128
-static bool hvsi_recv_data(struct hvsi_struct *hp, struct tty_struct *tty,
-		const uint8_t *packet)
+static bool hvsi_recv_data(struct hvsi_struct *hp, const uint8_t *packet)
 {
 	const struct hvsi_header *header = (const struct hvsi_header *)packet;
 	const uint8_t *data = packet + sizeof(struct hvsi_header);
@@ -377,7 +375,7 @@ static bool hvsi_recv_data(struct hvsi_struct *hp, struct tty_struct *tty,
 		datalen = TTY_THRESHOLD_THROTTLE;
 	}
 
-	hvsi_insert_chars(hp, tty, data, datalen);
+	hvsi_insert_chars(hp, data, datalen);
 
 	if (overflow > 0) {
 		/*
@@ -438,9 +436,7 @@ static int hvsi_load_chunk(struct hvsi_struct *hp, struct tty_struct *tty,
 			case VS_DATA_PACKET_HEADER:
 				if (!is_open(hp))
 					break;
-				if (tty == NULL)
-					break; /* no tty buffer to put data in */
-				flip = hvsi_recv_data(hp, tty, packet);
+				flip = hvsi_recv_data(hp, packet);
 				break;
 			case VS_CONTROL_PACKET_HEADER:
 				hvsi_recv_control(hp, packet, tty, handshake);
@@ -469,17 +465,17 @@ static int hvsi_load_chunk(struct hvsi_struct *hp, struct tty_struct *tty,
 	compact_inbuf(hp, packet);
 
 	if (flip)
-		tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(&hp->port);
 
 	return 1;
 }
 
-static void hvsi_send_overflow(struct hvsi_struct *hp, struct tty_struct *tty)
+static void hvsi_send_overflow(struct hvsi_struct *hp)
 {
 	pr_debug("%s: delivering %i bytes overflow\n", __func__,
 			hp->n_throttle);
 
-	hvsi_insert_chars(hp, tty, hp->throttle_buf, hp->n_throttle);
+	hvsi_insert_chars(hp, hp->throttle_buf, hp->n_throttle);
 	hp->n_throttle = 0;
 }
 
@@ -514,8 +510,8 @@ static irqreturn_t hvsi_interrupt(int irq, void *arg)
 	if (tty && hp->n_throttle && !test_bit(TTY_THROTTLED, &tty->flags)) {
 		/* we weren't hung up and we weren't throttled, so we can
 		 * deliver the rest now */
-		hvsi_send_overflow(hp, tty);
-		tty_flip_buffer_push(tty);
+		hvsi_send_overflow(hp);
+		tty_flip_buffer_push(&hp->port);
 	}
 	spin_unlock_irqrestore(&hp->lock, flags);
 
@@ -1001,8 +997,8 @@ static void hvsi_unthrottle(struct tty_struct *tty)
 
 	spin_lock_irqsave(&hp->lock, flags);
 	if (hp->n_throttle) {
-		hvsi_send_overflow(hp, tty);
-		tty_flip_buffer_push(tty);
+		hvsi_send_overflow(hp);
+		tty_flip_buffer_push(&hp->port);
 	}
 	spin_unlock_irqrestore(&hp->lock, flags);
 
@@ -1187,9 +1183,7 @@ static int __init hvsi_console_init(void)
 	hvsi_wait = poll_for_state; /* no irqs yet; must poll */
 
 	/* search device tree for vty nodes */
-	for (vty = of_find_compatible_node(NULL, "serial", "hvterm-protocol");
-			vty != NULL;
-			vty = of_find_compatible_node(vty, "serial", "hvterm-protocol")) {
+	for_each_compatible_node(vty, "serial", "hvterm-protocol") {
 		struct hvsi_struct *hp;
 		const uint32_t *vtermno, *irq;
 
diff --git a/drivers/tty/ipwireless/tty.c b/drivers/tty/ipwireless/tty.c
index 2cde13ddf9f..8fd72ff9436 100644
--- a/drivers/tty/ipwireless/tty.c
+++ b/drivers/tty/ipwireless/tty.c
@@ -106,7 +106,7 @@ static int ipw_open(struct tty_struct *linux_tty, struct file *filp)
 
 	tty->port.tty = linux_tty;
 	linux_tty->driver_data = tty;
-	linux_tty->low_latency = 1;
+	tty->port.low_latency = 1;
 
 	if (tty->tty_type == TTYTYPE_MODEM)
 		ipwireless_ppp_open(tty->network);
@@ -160,15 +160,9 @@ static void ipw_close(struct tty_struct *linux_tty, struct file *filp)
 void ipwireless_tty_received(struct ipw_tty *tty, unsigned char *data,
 			unsigned int length)
 {
-	struct tty_struct *linux_tty;
 	int work = 0;
 
 	mutex_lock(&tty->ipw_tty_mutex);
-	linux_tty = tty->port.tty;
-	if (linux_tty == NULL) {
-		mutex_unlock(&tty->ipw_tty_mutex);
-		return;
-	}
 
 	if (!tty->port.count) {
 		mutex_unlock(&tty->ipw_tty_mutex);
@@ -176,7 +170,7 @@ void ipwireless_tty_received(struct ipw_tty *tty, unsigned char *data,
 	}
 	mutex_unlock(&tty->ipw_tty_mutex);
 
-	work = tty_insert_flip_string(linux_tty, data, length);
+	work = tty_insert_flip_string(&tty->port, data, length);
 
 	if (work != length)
 		printk(KERN_DEBUG IPWIRELESS_PCCARD_NAME
@@ -187,7 +181,7 @@ void ipwireless_tty_received(struct ipw_tty *tty, unsigned char *data,
 	 * This may sleep if ->low_latency is set
 	 */
 	if (work)
-		tty_flip_buffer_push(linux_tty);
+		tty_flip_buffer_push(&tty->port);
 }
 
 static void ipw_write_packet_sent_callback(void *callback_data,
diff --git a/drivers/tty/isicom.c b/drivers/tty/isicom.c
index 3205b2e9090..858291ca889 100644
--- a/drivers/tty/isicom.c
+++ b/drivers/tty/isicom.c
@@ -634,10 +634,10 @@ static irqreturn_t isicom_interrupt(int irq, void *dev_id)
 			break;
 
 		case 1:	/* Received Break !!! */
-			tty_insert_flip_char(tty, 0, TTY_BREAK);
+			tty_insert_flip_char(&port->port, 0, TTY_BREAK);
 			if (port->port.flags & ASYNC_SAK)
 				do_SAK(tty);
-			tty_flip_buffer_push(tty);
+			tty_flip_buffer_push(&port->port);
 			break;
 
 		case 2:	/* Statistics		 */
@@ -650,15 +650,15 @@ static irqreturn_t isicom_interrupt(int irq, void *dev_id)
 			break;
 		}
 	} else {				/* Data   Packet */
-
-		count = tty_prepare_flip_string(tty, &rp, byte_count & ~1);
+		count = tty_prepare_flip_string(&port->port, &rp,
+				byte_count & ~1);
 		pr_debug("%s: Can rx %d of %d bytes.\n",
 			 __func__, count, byte_count);
 		word_count = count >> 1;
 		insw(base, rp, word_count);
 		byte_count -= (word_count << 1);
 		if (count & 0x0001) {
-			tty_insert_flip_char(tty,  inw(base) & 0xff,
+			tty_insert_flip_char(&port->port, inw(base) & 0xff,
 				TTY_NORMAL);
 			byte_count -= 2;
 		}
@@ -671,7 +671,7 @@ static irqreturn_t isicom_interrupt(int irq, void *dev_id)
 				byte_count -= 2;
 			}
 		}
-		tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(&port->port);
 	}
 	outw(0x0000, base+0x04); /* enable interrupts */
 	spin_unlock(&card->card_lock);
diff --git a/drivers/tty/metag_da.c b/drivers/tty/metag_da.c
new file mode 100644
index 00000000000..0e888621f48
--- /dev/null
+++ b/drivers/tty/metag_da.c
@@ -0,0 +1,677 @@
+/*
+ *  dashtty.c - tty driver for Dash channels interface.
+ *
+ *  Copyright (C) 2007,2008,2012 Imagination Technologies
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ *
+ */
+
+#include <linux/atomic.h>
+#include <linux/completion.h>
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/mutex.h>
+#include <linux/sched.h>
+#include <linux/serial.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/timer.h>
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+#include <linux/tty_flip.h>
+#include <linux/uaccess.h>
+
+#include <asm/da.h>
+
+/* Channel error codes */
+#define CONAOK	0
+#define CONERR	1
+#define CONBAD	2
+#define CONPRM	3
+#define CONADR	4
+#define CONCNT	5
+#define CONCBF	6
+#define CONCBE	7
+#define CONBSY	8
+
+/* Default channel for the console */
+#define CONSOLE_CHANNEL      1
+
+#define NUM_TTY_CHANNELS     6
+
+/* Auto allocate */
+#define DA_TTY_MAJOR        0
+
+/* A speedy poll rate helps the userland debug process connection response.
+ * But, if you set it too high then no other userland processes get much
+ * of a look in.
+ */
+#define DA_TTY_POLL (HZ / 50)
+
+/*
+ * A short put delay improves latency but has a high throughput overhead
+ */
+#define DA_TTY_PUT_DELAY (HZ / 100)
+
+static atomic_t num_channels_need_poll = ATOMIC_INIT(0);
+
+static struct timer_list poll_timer;
+
+static struct tty_driver *channel_driver;
+
+static struct timer_list put_timer;
+static struct task_struct *dashtty_thread;
+
+#define RX_BUF_SIZE 1024
+
+enum {
+	INCHR = 1,
+	OUTCHR,
+	RDBUF,
+	WRBUF,
+	RDSTAT
+};
+
+/**
+ * struct dashtty_port - Wrapper struct for dashtty tty_port.
+ * @port:		TTY port data
+ * @rx_lock:		Lock for rx_buf.
+ *			This protects between the poll timer and user context.
+ *			It's also held during read SWITCH operations.
+ * @rx_buf:		Read buffer
+ * @xmit_lock:		Lock for xmit_*, and port.xmit_buf.
+ *			This protects between user context and kernel thread.
+ *			It's also held during write SWITCH operations.
+ * @xmit_cnt:		Size of xmit buffer contents
+ * @xmit_head:		Head of xmit buffer where data is written
+ * @xmit_tail:		Tail of xmit buffer where data is read
+ * @xmit_empty:		Completion for xmit buffer being empty
+ */
+struct dashtty_port {
+	struct tty_port		 port;
+	spinlock_t		 rx_lock;
+	void			*rx_buf;
+	struct mutex		 xmit_lock;
+	unsigned int		 xmit_cnt;
+	unsigned int		 xmit_head;
+	unsigned int		 xmit_tail;
+	struct completion	 xmit_empty;
+};
+
+static struct dashtty_port dashtty_ports[NUM_TTY_CHANNELS];
+
+static atomic_t dashtty_xmit_cnt = ATOMIC_INIT(0);
+static wait_queue_head_t dashtty_waitqueue;
+
+/*
+ * Low-level DA channel access routines
+ */
+static int chancall(int in_bios_function, int in_channel,
+		    int in_arg2, void *in_arg3,
+		    void *in_arg4)
+{
+	register int   bios_function asm("D1Ar1") = in_bios_function;
+	register int   channel       asm("D0Ar2") = in_channel;
+	register int   arg2          asm("D1Ar3") = in_arg2;
+	register void *arg3          asm("D0Ar4") = in_arg3;
+	register void *arg4          asm("D1Ar5") = in_arg4;
+	register int   bios_call     asm("D0Ar6") = 3;
+	register int   result        asm("D0Re0");
+
+	asm volatile (
+		"MSETL	[A0StP++], %6,%4,%2\n\t"
+		"ADD	A0StP, A0StP, #8\n\t"
+		"SWITCH	#0x0C30208\n\t"
+		"GETD	%0, [A0StP+#-8]\n\t"
+		"SUB	A0StP, A0StP, #(4*6)+8\n\t"
+		: "=d" (result)   /* outs */
+		: "d" (bios_function),
+		  "d" (channel),
+		  "d" (arg2),
+		  "d" (arg3),
+		  "d" (arg4),
+		  "d" (bios_call) /* ins */
+		: "memory");
+
+	return result;
+}
+
+/*
+ * Attempts to fetch count bytes from channel and returns actual count.
+ */
+static int fetch_data(unsigned int channel)
+{
+	struct dashtty_port *dport = &dashtty_ports[channel];
+	int received = 0;
+
+	spin_lock_bh(&dport->rx_lock);
+	/* check the port isn't being shut down */
+	if (!dport->rx_buf)
+		goto unlock;
+	if (chancall(RDBUF, channel, RX_BUF_SIZE,
+		     (void *)dport->rx_buf, &received) == CONAOK) {
+		if (received) {
+			int space;
+			unsigned char *cbuf;
+
+			space = tty_prepare_flip_string(&dport->port, &cbuf,
+							received);
+
+			if (space <= 0)
+				goto unlock;
+
+			memcpy(cbuf, dport->rx_buf, space);
+			tty_flip_buffer_push(&dport->port);
+		}
+	}
+unlock:
+	spin_unlock_bh(&dport->rx_lock);
+
+	return received;
+}
+
+/**
+ * find_channel_to_poll() - Returns number of the next channel to poll.
+ * Returns:	The number of the next channel to poll, or -1 if none need
+ *		polling.
+ */
+static int find_channel_to_poll(void)
+{
+	static int last_polled_channel;
+	int last = last_polled_channel;
+	int chan;
+	struct dashtty_port *dport;
+
+	for (chan = last + 1; ; ++chan) {
+		if (chan >= NUM_TTY_CHANNELS)
+			chan = 0;
+
+		dport = &dashtty_ports[chan];
+		if (dport->rx_buf) {
+			last_polled_channel = chan;
+			return chan;
+		}
+
+		if (chan == last)
+			break;
+	}
+	return -1;
+}
+
+/**
+ * put_channel_data() - Write out a block of channel data.
+ * @chan:	DA channel number.
+ *
+ * Write a single block of data out to the debug adapter. If the circular buffer
+ * is wrapped then only the first block is written.
+ *
+ * Returns:	1 if the remote buffer was too full to accept data.
+ *		0 otherwise.
+ */
+static int put_channel_data(unsigned int chan)
+{
+	struct dashtty_port *dport;
+	struct tty_struct *tty;
+	int number_written;
+	unsigned int count = 0;
+
+	dport = &dashtty_ports[chan];
+	mutex_lock(&dport->xmit_lock);
+	if (dport->xmit_cnt) {
+		count = min((unsigned int)(SERIAL_XMIT_SIZE - dport->xmit_tail),
+			    dport->xmit_cnt);
+		chancall(WRBUF, chan, count,
+			 dport->port.xmit_buf + dport->xmit_tail,
+			 &number_written);
+		dport->xmit_cnt -= number_written;
+		if (!dport->xmit_cnt) {
+			/* reset pointers to avoid wraps */
+			dport->xmit_head = 0;
+			dport->xmit_tail = 0;
+			complete(&dport->xmit_empty);
+		} else {
+			dport->xmit_tail += number_written;
+			if (dport->xmit_tail >= SERIAL_XMIT_SIZE)
+				dport->xmit_tail -= SERIAL_XMIT_SIZE;
+		}
+		atomic_sub(number_written, &dashtty_xmit_cnt);
+	}
+	mutex_unlock(&dport->xmit_lock);
+
+	/* if we've made more data available, wake up tty */
+	if (count && number_written) {
+		tty = tty_port_tty_get(&dport->port);
+		if (tty) {
+			tty_wakeup(tty);
+			tty_kref_put(tty);
+		}
+	}
+
+	/* did the write fail? */
+	return count && !number_written;
+}
+
+/**
+ * put_data() - Kernel thread to write out blocks of channel data to DA.
+ * @arg:	Unused.
+ *
+ * This kernel thread runs while @dashtty_xmit_cnt != 0, and loops over the
+ * channels to write out any buffered data. If any of the channels stall due to
+ * the remote buffer being full, a hold off happens to allow the debugger to
+ * drain the buffer.
+ */
+static int put_data(void *arg)
+{
+	unsigned int chan, stall;
+
+	__set_current_state(TASK_RUNNING);
+	while (!kthread_should_stop()) {
+		/*
+		 * For each channel see if there's anything to transmit in the
+		 * port's xmit_buf.
+		 */
+		stall = 0;
+		for (chan = 0; chan < NUM_TTY_CHANNELS; ++chan)
+			stall += put_channel_data(chan);
+
+		/*
+		 * If some of the buffers are full, hold off for a short while
+		 * to allow them to empty.
+		 */
+		if (stall)
+			msleep(25);
+
+		wait_event_interruptible(dashtty_waitqueue,
+					 atomic_read(&dashtty_xmit_cnt));
+	}
+
+	return 0;
+}
+
+/*
+ *	This gets called every DA_TTY_POLL and polls the channels for data
+ */
+static void dashtty_timer(unsigned long ignored)
+{
+	int channel;
+
+	/* If there are no ports open do nothing and don't poll again. */
+	if (!atomic_read(&num_channels_need_poll))
+		return;
+
+	channel = find_channel_to_poll();
+
+	/* Did we find a channel to poll? */
+	if (channel >= 0)
+		fetch_data(channel);
+
+	mod_timer_pinned(&poll_timer, jiffies + DA_TTY_POLL);
+}
+
+static void add_poll_timer(struct timer_list *poll_timer)
+{
+	setup_timer(poll_timer, dashtty_timer, 0);
+	poll_timer->expires = jiffies + DA_TTY_POLL;
+
+	/*
+	 * Always attach the timer to the boot CPU. The DA channels are per-CPU
+	 * so all polling should be from a single CPU.
+	 */
+	add_timer_on(poll_timer, 0);
+}
+
+static int dashtty_port_activate(struct tty_port *port, struct tty_struct *tty)
+{
+	struct dashtty_port *dport = container_of(port, struct dashtty_port,
+						  port);
+	void *rx_buf;
+
+	/* Allocate the buffer we use for writing data */
+	if (tty_port_alloc_xmit_buf(port) < 0)
+		goto err;
+
+	/* Allocate the buffer we use for reading data */
+	rx_buf = kzalloc(RX_BUF_SIZE, GFP_KERNEL);
+	if (!rx_buf)
+		goto err_free_xmit;
+
+	spin_lock_bh(&dport->rx_lock);
+	dport->rx_buf = rx_buf;
+	spin_unlock_bh(&dport->rx_lock);
+
+	/*
+	 * Don't add the poll timer if we're opening a console. This
+	 * avoids the overhead of polling the Dash but means it is not
+	 * possible to have a login on /dev/console.
+	 *
+	 */
+	if (dport != &dashtty_ports[CONSOLE_CHANNEL])
+		if (atomic_inc_return(&num_channels_need_poll) == 1)
+			add_poll_timer(&poll_timer);
+
+	return 0;
+err_free_xmit:
+	tty_port_free_xmit_buf(port);
+err:
+	return -ENOMEM;
+}
+
+static void dashtty_port_shutdown(struct tty_port *port)
+{
+	struct dashtty_port *dport = container_of(port, struct dashtty_port,
+						  port);
+	void *rx_buf;
+	unsigned int count;
+
+	/* stop reading */
+	if (dport != &dashtty_ports[CONSOLE_CHANNEL])
+		if (atomic_dec_and_test(&num_channels_need_poll))
+			del_timer_sync(&poll_timer);
+
+	mutex_lock(&dport->xmit_lock);
+	count = dport->xmit_cnt;
+	mutex_unlock(&dport->xmit_lock);
+	if (count) {
+		/*
+		 * There's still data to write out, so wake and wait for the
+		 * writer thread to drain the buffer.
+		 */
+		del_timer(&put_timer);
+		wake_up_interruptible(&dashtty_waitqueue);
+		wait_for_completion(&dport->xmit_empty);
+	}
+
+	/* Null the read buffer (timer could still be running!) */
+	spin_lock_bh(&dport->rx_lock);
+	rx_buf = dport->rx_buf;
+	dport->rx_buf = NULL;
+	spin_unlock_bh(&dport->rx_lock);
+	/* Free the read buffer */
+	kfree(rx_buf);
+
+	/* Free the write buffer */
+	tty_port_free_xmit_buf(port);
+}
+
+static const struct tty_port_operations dashtty_port_ops = {
+	.activate	= dashtty_port_activate,
+	.shutdown	= dashtty_port_shutdown,
+};
+
+static int dashtty_install(struct tty_driver *driver, struct tty_struct *tty)
+{
+	return tty_port_install(&dashtty_ports[tty->index].port, driver, tty);
+}
+
+static int dashtty_open(struct tty_struct *tty, struct file *filp)
+{
+	return tty_port_open(tty->port, tty, filp);
+}
+
+static void dashtty_close(struct tty_struct *tty, struct file *filp)
+{
+	return tty_port_close(tty->port, tty, filp);
+}
+
+static void dashtty_hangup(struct tty_struct *tty)
+{
+	int channel;
+	struct dashtty_port *dport;
+
+	channel = tty->index;
+	dport = &dashtty_ports[channel];
+
+	/* drop any data in the xmit buffer */
+	mutex_lock(&dport->xmit_lock);
+	if (dport->xmit_cnt) {
+		atomic_sub(dport->xmit_cnt, &dashtty_xmit_cnt);
+		dport->xmit_cnt = 0;
+		dport->xmit_head = 0;
+		dport->xmit_tail = 0;
+		complete(&dport->xmit_empty);
+	}
+	mutex_unlock(&dport->xmit_lock);
+
+	tty_port_hangup(tty->port);
+}
+
+/**
+ * dashtty_put_timer() - Delayed wake up of kernel thread.
+ * @ignored:	unused
+ *
+ * This timer function wakes up the kernel thread if any data exists in the
+ * buffers. It is used to delay the expensive writeout until the writer has
+ * stopped writing.
+ */
+static void dashtty_put_timer(unsigned long ignored)
+{
+	if (atomic_read(&dashtty_xmit_cnt))
+		wake_up_interruptible(&dashtty_waitqueue);
+}
+
+static int dashtty_write(struct tty_struct *tty, const unsigned char *buf,
+			 int total)
+{
+	int channel, count, block;
+	struct dashtty_port *dport;
+
+	/* Determine the channel */
+	channel = tty->index;
+	dport = &dashtty_ports[channel];
+
+	/*
+	 * Write to output buffer.
+	 *
+	 * The reason that we asynchronously write the buffer is because if we
+	 * were to write the buffer synchronously then because DA channels are
+	 * per-CPU the buffer would be written to the channel of whatever CPU
+	 * we're running on.
+	 *
+	 * What we actually want to happen is have all input and output done on
+	 * one CPU.
+	 */
+	mutex_lock(&dport->xmit_lock);
+	/* work out how many bytes we can write to the xmit buffer */
+	total = min(total, (int)(SERIAL_XMIT_SIZE - dport->xmit_cnt));
+	atomic_add(total, &dashtty_xmit_cnt);
+	dport->xmit_cnt += total;
+	/* write the actual bytes (may need splitting if it wraps) */
+	for (count = total; count; count -= block) {
+		block = min(count, (int)(SERIAL_XMIT_SIZE - dport->xmit_head));
+		memcpy(dport->port.xmit_buf + dport->xmit_head, buf, block);
+		dport->xmit_head += block;
+		if (dport->xmit_head >= SERIAL_XMIT_SIZE)
+			dport->xmit_head -= SERIAL_XMIT_SIZE;
+		buf += block;
+	}
+	count = dport->xmit_cnt;
+	/* xmit buffer no longer empty? */
+	if (count)
+		INIT_COMPLETION(dport->xmit_empty);
+	mutex_unlock(&dport->xmit_lock);
+
+	if (total) {
+		/*
+		 * If the buffer is full, wake up the kthread, otherwise allow
+		 * some more time for the buffer to fill up a bit before waking
+		 * it.
+		 */
+		if (count == SERIAL_XMIT_SIZE) {
+			del_timer(&put_timer);
+			wake_up_interruptible(&dashtty_waitqueue);
+		} else {
+			mod_timer(&put_timer, jiffies + DA_TTY_PUT_DELAY);
+		}
+	}
+	return total;
+}
+
+static int dashtty_write_room(struct tty_struct *tty)
+{
+	struct dashtty_port *dport;
+	int channel;
+	int room;
+
+	channel = tty->index;
+	dport = &dashtty_ports[channel];
+
+	/* report the space in the xmit buffer */
+	mutex_lock(&dport->xmit_lock);
+	room = SERIAL_XMIT_SIZE - dport->xmit_cnt;
+	mutex_unlock(&dport->xmit_lock);
+
+	return room;
+}
+
+static int dashtty_chars_in_buffer(struct tty_struct *tty)
+{
+	struct dashtty_port *dport;
+	int channel;
+	int chars;
+
+	channel = tty->index;
+	dport = &dashtty_ports[channel];
+
+	/* report the number of bytes in the xmit buffer */
+	mutex_lock(&dport->xmit_lock);
+	chars = dport->xmit_cnt;
+	mutex_unlock(&dport->xmit_lock);
+
+	return chars;
+}
+
+static const struct tty_operations dashtty_ops = {
+	.install		= dashtty_install,
+	.open			= dashtty_open,
+	.close			= dashtty_close,
+	.hangup			= dashtty_hangup,
+	.write			= dashtty_write,
+	.write_room		= dashtty_write_room,
+	.chars_in_buffer	= dashtty_chars_in_buffer,
+};
+
+static int __init dashtty_init(void)
+{
+	int ret;
+	int nport;
+	struct dashtty_port *dport;
+
+	if (!metag_da_enabled())
+		return -ENODEV;
+
+	channel_driver = tty_alloc_driver(NUM_TTY_CHANNELS,
+					  TTY_DRIVER_REAL_RAW);
+	if (IS_ERR(channel_driver))
+		return PTR_ERR(channel_driver);
+
+	channel_driver->driver_name = "metag_da";
+	channel_driver->name = "ttyDA";
+	channel_driver->major = DA_TTY_MAJOR;
+	channel_driver->minor_start = 0;
+	channel_driver->type = TTY_DRIVER_TYPE_SERIAL;
+	channel_driver->subtype = SERIAL_TYPE_NORMAL;
+	channel_driver->init_termios = tty_std_termios;
+	channel_driver->init_termios.c_cflag |= CLOCAL;
+
+	tty_set_operations(channel_driver, &dashtty_ops);
+	for (nport = 0; nport < NUM_TTY_CHANNELS; nport++) {
+		dport = &dashtty_ports[nport];
+		tty_port_init(&dport->port);
+		dport->port.ops = &dashtty_port_ops;
+		spin_lock_init(&dport->rx_lock);
+		mutex_init(&dport->xmit_lock);
+		/* the xmit buffer starts empty, i.e. completely written */
+		init_completion(&dport->xmit_empty);
+		complete(&dport->xmit_empty);
+	}
+
+	setup_timer(&put_timer, dashtty_put_timer, 0);
+
+	init_waitqueue_head(&dashtty_waitqueue);
+	dashtty_thread = kthread_create(put_data, NULL, "ttyDA");
+	if (IS_ERR(dashtty_thread)) {
+		pr_err("Couldn't create dashtty thread\n");
+		ret = PTR_ERR(dashtty_thread);
+		goto err_destroy_ports;
+	}
+	/*
+	 * Bind the writer thread to the boot CPU so it can't migrate.
+	 * DA channels are per-CPU and we want all channel I/O to be on a single
+	 * predictable CPU.
+	 */
+	kthread_bind(dashtty_thread, 0);
+	wake_up_process(dashtty_thread);
+
+	ret = tty_register_driver(channel_driver);
+
+	if (ret < 0) {
+		pr_err("Couldn't install dashtty driver: err %d\n",
+		       ret);
+		goto err_stop_kthread;
+	}
+
+	return 0;
+
+err_stop_kthread:
+	kthread_stop(dashtty_thread);
+err_destroy_ports:
+	for (nport = 0; nport < NUM_TTY_CHANNELS; nport++) {
+		dport = &dashtty_ports[nport];
+		tty_port_destroy(&dport->port);
+	}
+	put_tty_driver(channel_driver);
+	return ret;
+}
+
+static void dashtty_exit(void)
+{
+	int nport;
+	struct dashtty_port *dport;
+
+	del_timer_sync(&put_timer);
+	kthread_stop(dashtty_thread);
+	del_timer_sync(&poll_timer);
+	tty_unregister_driver(channel_driver);
+	for (nport = 0; nport < NUM_TTY_CHANNELS; nport++) {
+		dport = &dashtty_ports[nport];
+		tty_port_destroy(&dport->port);
+	}
+	put_tty_driver(channel_driver);
+}
+
+module_init(dashtty_init);
+module_exit(dashtty_exit);
+
+#ifdef CONFIG_DA_CONSOLE
+
+static void dash_console_write(struct console *co, const char *s,
+			       unsigned int count)
+{
+	int actually_written;
+
+	chancall(WRBUF, CONSOLE_CHANNEL, count, (void *)s, &actually_written);
+}
+
+static struct tty_driver *dash_console_device(struct console *c, int *index)
+{
+	*index = c->index;
+	return channel_driver;
+}
+
+struct console dash_console = {
+	.name = "ttyDA",
+	.write = dash_console_write,
+	.device = dash_console_device,
+	.flags = CON_PRINTBUFFER,
+	.index = 1,
+};
+
+#endif
diff --git a/drivers/tty/moxa.c b/drivers/tty/moxa.c
index f9d28503bde..adeac255e52 100644
--- a/drivers/tty/moxa.c
+++ b/drivers/tty/moxa.c
@@ -1405,7 +1405,7 @@ static int moxa_poll_port(struct moxa_port *p, unsigned int handle,
 		if (inited && !test_bit(TTY_THROTTLED, &tty->flags) &&
 				MoxaPortRxQueue(p) > 0) { /* RX */
 			MoxaPortReadData(p);
-			tty_schedule_flip(tty);
+			tty_schedule_flip(&p->port);
 		}
 	} else {
 		clear_bit(EMPTYWAIT, &p->statusflags);
@@ -1429,8 +1429,8 @@ static int moxa_poll_port(struct moxa_port *p, unsigned int handle,
 		goto put;
 
 	if (tty && (intr & IntrBreak) && !I_IGNBRK(tty)) { /* BREAK */
-		tty_insert_flip_char(tty, 0, TTY_BREAK);
-		tty_schedule_flip(tty);
+		tty_insert_flip_char(&p->port, 0, TTY_BREAK);
+		tty_schedule_flip(&p->port);
 	}
 
 	if (intr & IntrLine)
@@ -1966,7 +1966,7 @@ static int MoxaPortReadData(struct moxa_port *port)
 			ofs = baseAddr + DynPage_addr + bufhead + head;
 			len = (tail >= head) ? (tail - head) :
 					(rx_mask + 1 - head);
-			len = tty_prepare_flip_string(tty, &dst,
+			len = tty_prepare_flip_string(&port->port, &dst,
 					min(len, count));
 			memcpy_fromio(dst, ofs, len);
 			head = (head + len) & rx_mask;
@@ -1978,7 +1978,7 @@ static int MoxaPortReadData(struct moxa_port *port)
 		while (count > 0) {
 			writew(pageno, baseAddr + Control_reg);
 			ofs = baseAddr + DynPage_addr + pageofs;
-			len = tty_prepare_flip_string(tty, &dst,
+			len = tty_prepare_flip_string(&port->port, &dst,
 					min(Page_size - pageofs, count));
 			memcpy_fromio(dst, ofs, len);
 
diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index 40113868bec..484b6a3c9b0 100644
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -1264,7 +1264,7 @@ static int mxser_set_serial_info(struct tty_struct *tty,
 				(new_serial.flags & ASYNC_FLAGS));
 		port->close_delay = new_serial.close_delay * HZ / 100;
 		port->closing_wait = new_serial.closing_wait * HZ / 100;
-		tty->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
+		port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 		if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST &&
 				(new_serial.baud_base != info->baud_base ||
 				new_serial.custom_divisor !=
@@ -2079,7 +2079,7 @@ static void mxser_receive_chars(struct tty_struct *tty,
 		}
 		while (gdl--) {
 			ch = inb(port->ioaddr + UART_RX);
-			tty_insert_flip_char(tty, ch, 0);
+			tty_insert_flip_char(&port->port, ch, 0);
 			cnt++;
 		}
 		goto end_intr;
@@ -2118,7 +2118,7 @@ intr_old:
 				} else
 					flag = TTY_BREAK;
 			}
-			tty_insert_flip_char(tty, ch, flag);
+			tty_insert_flip_char(&port->port, ch, flag);
 			cnt++;
 			if (cnt >= recv_room) {
 				if (!port->ldisc_stop_rx)
@@ -2145,7 +2145,7 @@ end_intr:
 	 * recursive locking.
 	 */
 	spin_unlock(&port->slock);
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&port->port);
 	spin_lock(&port->slock);
 }
 
@@ -2364,7 +2364,6 @@ static void mxser_release_vector(struct mxser_board *brd)
 
 static void mxser_release_ISA_res(struct mxser_board *brd)
 {
-	free_irq(brd->irq, brd);
 	release_region(brd->ports[0].ioaddr, 8 * brd->info->nports);
 	mxser_release_vector(brd);
 }
@@ -2430,6 +2429,7 @@ static void mxser_board_remove(struct mxser_board *brd)
 		tty_unregister_device(mxvar_sdriver, brd->idx + i);
 		tty_port_destroy(&brd->ports[i].port);
 	}
+	free_irq(brd->irq, brd);
 }
 
 static int __init mxser_get_ISA_conf(int cap, struct mxser_board *brd)
@@ -2554,6 +2554,7 @@ static int mxser_probe(struct pci_dev *pdev,
 	struct mxser_board *brd;
 	unsigned int i, j;
 	unsigned long ioaddress;
+	struct device *tty_dev;
 	int retval = -EINVAL;
 
 	for (i = 0; i < MXSER_BOARDS; i++)
@@ -2637,13 +2638,25 @@ static int mxser_probe(struct pci_dev *pdev,
 	if (retval)
 		goto err_rel3;
 
-	for (i = 0; i < brd->info->nports; i++)
-		tty_port_register_device(&brd->ports[i].port, mxvar_sdriver,
-				brd->idx + i, &pdev->dev);
+	for (i = 0; i < brd->info->nports; i++) {
+		tty_dev = tty_port_register_device(&brd->ports[i].port,
+				mxvar_sdriver, brd->idx + i, &pdev->dev);
+		if (IS_ERR(tty_dev)) {
+			retval = PTR_ERR(tty_dev);
+			for (i--; i >= 0; i--)
+				tty_unregister_device(mxvar_sdriver,
+					brd->idx + i);
+			goto err_relbrd;
+		}
+	}
 
 	pci_set_drvdata(pdev, brd);
 
 	return 0;
+err_relbrd:
+	for (i = 0; i < brd->info->nports; i++)
+		tty_port_destroy(&brd->ports[i].port);
+	free_irq(brd->irq, brd);
 err_rel3:
 	pci_release_region(pdev, 3);
 err_zero:
@@ -2665,7 +2678,6 @@ static void mxser_remove(struct pci_dev *pdev)
 
 	mxser_board_remove(brd);
 
-	free_irq(pdev->irq, brd);
 	pci_release_region(pdev, 2);
 	pci_release_region(pdev, 3);
 	pci_disable_device(pdev);
@@ -2683,6 +2695,7 @@ static struct pci_driver mxser_driver = {
 static int __init mxser_module_init(void)
 {
 	struct mxser_board *brd;
+	struct device *tty_dev;
 	unsigned int b, i, m;
 	int retval;
 
@@ -2728,14 +2741,29 @@ static int __init mxser_module_init(void)
 
 		/* mxser_initbrd will hook ISR. */
 		if (mxser_initbrd(brd, NULL) < 0) {
+			mxser_release_ISA_res(brd);
 			brd->info = NULL;
 			continue;
 		}
 
 		brd->idx = m * MXSER_PORTS_PER_BOARD;
-		for (i = 0; i < brd->info->nports; i++)
-			tty_port_register_device(&brd->ports[i].port,
+		for (i = 0; i < brd->info->nports; i++) {
+			tty_dev = tty_port_register_device(&brd->ports[i].port,
 					mxvar_sdriver, brd->idx + i, NULL);
+			if (IS_ERR(tty_dev)) {
+				for (i--; i >= 0; i--)
+					tty_unregister_device(mxvar_sdriver,
+						brd->idx + i);
+				for (i = 0; i < brd->info->nports; i++)
+					tty_port_destroy(&brd->ports[i].port);
+				free_irq(brd->irq, brd);
+				mxser_release_ISA_res(brd);
+				brd->info = NULL;
+				break;
+			}
+		}
+		if (brd->info == NULL)
+			continue;
 
 		m++;
 	}
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index dcc0430a49c..4a43ef5d796 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -1067,9 +1067,9 @@ static void gsm_process_modem(struct tty_struct *tty, struct gsm_dlci *dlci,
 		if ((mlines & TIOCM_CD) == 0 && (dlci->modem_rx & TIOCM_CD))
 			if (!(tty->termios.c_cflag & CLOCAL))
 				tty_hangup(tty);
-		if (brk & 0x01)
-			tty_insert_flip_char(tty, 0, TTY_BREAK);
 	}
+	if (brk & 0x01)
+		tty_insert_flip_char(&dlci->port, 0, TTY_BREAK);
 	dlci->modem_rx = mlines;
 }
 
@@ -1137,7 +1137,7 @@ static void gsm_control_modem(struct gsm_mux *gsm, u8 *data, int clen)
 
 static void gsm_control_rls(struct gsm_mux *gsm, u8 *data, int clen)
 {
-	struct tty_struct *tty;
+	struct tty_port *port;
 	unsigned int addr = 0 ;
 	u8 bits;
 	int len = clen;
@@ -1160,19 +1160,18 @@ static void gsm_control_rls(struct gsm_mux *gsm, u8 *data, int clen)
 	bits = *dp;
 	if ((bits & 1) == 0)
 		return;
-	/* See if we have an uplink tty */
-	tty = tty_port_tty_get(&gsm->dlci[addr]->port);
 
-	if (tty) {
-		if (bits & 2)
-			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
-		if (bits & 4)
-			tty_insert_flip_char(tty, 0, TTY_PARITY);
-		if (bits & 8)
-			tty_insert_flip_char(tty, 0, TTY_FRAME);
-		tty_flip_buffer_push(tty);
-		tty_kref_put(tty);
-	}
+	port = &gsm->dlci[addr]->port;
+
+	if (bits & 2)
+		tty_insert_flip_char(port, 0, TTY_OVERRUN);
+	if (bits & 4)
+		tty_insert_flip_char(port, 0, TTY_PARITY);
+	if (bits & 8)
+		tty_insert_flip_char(port, 0, TTY_FRAME);
+
+	tty_flip_buffer_push(port);
+
 	gsm_control_reply(gsm, CMD_RLS, data, clen);
 }
 
@@ -1545,36 +1544,37 @@ static void gsm_dlci_data(struct gsm_dlci *dlci, u8 *data, int clen)
 {
 	/* krefs .. */
 	struct tty_port *port = &dlci->port;
-	struct tty_struct *tty = tty_port_tty_get(port);
+	struct tty_struct *tty;
 	unsigned int modem = 0;
 	int len = clen;
 
 	if (debug & 16)
-		pr_debug("%d bytes for tty %p\n", len, tty);
-	if (tty) {
-		switch (dlci->adaption)  {
-		/* Unsupported types */
-		/* Packetised interruptible data */
-		case 4:
-			break;
-		/* Packetised uininterruptible voice/data */
-		case 3:
-			break;
-		/* Asynchronous serial with line state in each frame */
-		case 2:
-			while (gsm_read_ea(&modem, *data++) == 0) {
-				len--;
-				if (len == 0)
-					return;
-			}
+		pr_debug("%d bytes for tty\n", len);
+	switch (dlci->adaption)  {
+	/* Unsupported types */
+	/* Packetised interruptible data */
+	case 4:
+		break;
+	/* Packetised uininterruptible voice/data */
+	case 3:
+		break;
+	/* Asynchronous serial with line state in each frame */
+	case 2:
+		while (gsm_read_ea(&modem, *data++) == 0) {
+			len--;
+			if (len == 0)
+				return;
+		}
+		tty = tty_port_tty_get(port);
+		if (tty) {
 			gsm_process_modem(tty, dlci, modem, clen);
-		/* Line state will go via DLCI 0 controls only */
-		case 1:
-		default:
-			tty_insert_flip_string(tty, data, len);
-			tty_flip_buffer_push(tty);
+			tty_kref_put(tty);
 		}
-		tty_kref_put(tty);
+	/* Line state will go via DLCI 0 controls only */
+	case 1:
+	default:
+		tty_insert_flip_string(port, data, len);
+		tty_flip_buffer_push(port);
 	}
 }
 
@@ -1689,6 +1689,8 @@ static inline void dlci_put(struct gsm_dlci *dlci)
 	tty_port_put(&dlci->port);
 }
 
+static void gsm_destroy_network(struct gsm_dlci *dlci);
+
 /**
  *	gsm_dlci_release		-	release DLCI
  *	@dlci: DLCI to destroy
@@ -1702,9 +1704,19 @@ static void gsm_dlci_release(struct gsm_dlci *dlci)
 {
 	struct tty_struct *tty = tty_port_tty_get(&dlci->port);
 	if (tty) {
+		mutex_lock(&dlci->mutex);
+		gsm_destroy_network(dlci);
+		mutex_unlock(&dlci->mutex);
+
+		/* tty_vhangup needs the tty_lock, so unlock and
+		   relock after doing the hangup. */
+		tty_unlock(tty);
 		tty_vhangup(tty);
+		tty_lock(tty);
+		tty_port_tty_set(&dlci->port, NULL);
 		tty_kref_put(tty);
 	}
+	dlci->state = DLCI_CLOSED;
 	dlci_put(dlci);
 }
 
@@ -2947,6 +2959,8 @@ static void gsmtty_close(struct tty_struct *tty, struct file *filp)
 
 	if (dlci == NULL)
 		return;
+	if (dlci->state == DLCI_CLOSED)
+		return;
 	mutex_lock(&dlci->mutex);
 	gsm_destroy_network(dlci);
 	mutex_unlock(&dlci->mutex);
@@ -2965,6 +2979,8 @@ out:
 static void gsmtty_hangup(struct tty_struct *tty)
 {
 	struct gsm_dlci *dlci = tty->driver_data;
+	if (dlci->state == DLCI_CLOSED)
+		return;
 	tty_port_hangup(&dlci->port);
 	gsm_dlci_begin_close(dlci);
 }
@@ -2972,9 +2988,12 @@ static void gsmtty_hangup(struct tty_struct *tty)
 static int gsmtty_write(struct tty_struct *tty, const unsigned char *buf,
 								    int len)
 {
+	int sent;
 	struct gsm_dlci *dlci = tty->driver_data;
+	if (dlci->state == DLCI_CLOSED)
+		return -EINVAL;
 	/* Stuff the bytes into the fifo queue */
-	int sent = kfifo_in_locked(dlci->fifo, buf, len, &dlci->lock);
+	sent = kfifo_in_locked(dlci->fifo, buf, len, &dlci->lock);
 	/* Need to kick the channel */
 	gsm_dlci_data_kick(dlci);
 	return sent;
@@ -2983,18 +3002,24 @@ static int gsmtty_write(struct tty_struct *tty, const unsigned char *buf,
 static int gsmtty_write_room(struct tty_struct *tty)
 {
 	struct gsm_dlci *dlci = tty->driver_data;
+	if (dlci->state == DLCI_CLOSED)
+		return -EINVAL;
 	return TX_SIZE - kfifo_len(dlci->fifo);
 }
 
 static int gsmtty_chars_in_buffer(struct tty_struct *tty)
 {
 	struct gsm_dlci *dlci = tty->driver_data;
+	if (dlci->state == DLCI_CLOSED)
+		return -EINVAL;
 	return kfifo_len(dlci->fifo);
 }
 
 static void gsmtty_flush_buffer(struct tty_struct *tty)
 {
 	struct gsm_dlci *dlci = tty->driver_data;
+	if (dlci->state == DLCI_CLOSED)
+		return;
 	/* Caution needed: If we implement reliable transport classes
 	   then the data being transmitted can't simply be junked once
 	   it has first hit the stack. Until then we can just blow it
@@ -3013,6 +3038,8 @@ static void gsmtty_wait_until_sent(struct tty_struct *tty, int timeout)
 static int gsmtty_tiocmget(struct tty_struct *tty)
 {
 	struct gsm_dlci *dlci = tty->driver_data;
+	if (dlci->state == DLCI_CLOSED)
+		return -EINVAL;
 	return dlci->modem_rx;
 }
 
@@ -3022,6 +3049,8 @@ static int gsmtty_tiocmset(struct tty_struct *tty,
 	struct gsm_dlci *dlci = tty->driver_data;
 	unsigned int modem_tx = dlci->modem_tx;
 
+	if (dlci->state == DLCI_CLOSED)
+		return -EINVAL;
 	modem_tx &= ~clear;
 	modem_tx |= set;
 
@@ -3040,6 +3069,8 @@ static int gsmtty_ioctl(struct tty_struct *tty,
 	struct gsm_netconfig nc;
 	int index;
 
+	if (dlci->state == DLCI_CLOSED)
+		return -EINVAL;
 	switch (cmd) {
 	case GSMIOC_ENABLE_NET:
 		if (copy_from_user(&nc, (void __user *)arg, sizeof(nc)))
@@ -3066,6 +3097,9 @@ static int gsmtty_ioctl(struct tty_struct *tty,
 
 static void gsmtty_set_termios(struct tty_struct *tty, struct ktermios *old)
 {
+	struct gsm_dlci *dlci = tty->driver_data;
+	if (dlci->state == DLCI_CLOSED)
+		return;
 	/* For the moment its fixed. In actual fact the speed information
 	   for the virtual channel can be propogated in both directions by
 	   the RPN control message. This however rapidly gets nasty as we
@@ -3077,6 +3111,8 @@ static void gsmtty_set_termios(struct tty_struct *tty, struct ktermios *old)
 static void gsmtty_throttle(struct tty_struct *tty)
 {
 	struct gsm_dlci *dlci = tty->driver_data;
+	if (dlci->state == DLCI_CLOSED)
+		return;
 	if (tty->termios.c_cflag & CRTSCTS)
 		dlci->modem_tx &= ~TIOCM_DTR;
 	dlci->throttled = 1;
@@ -3087,6 +3123,8 @@ static void gsmtty_throttle(struct tty_struct *tty)
 static void gsmtty_unthrottle(struct tty_struct *tty)
 {
 	struct gsm_dlci *dlci = tty->driver_data;
+	if (dlci->state == DLCI_CLOSED)
+		return;
 	if (tty->termios.c_cflag & CRTSCTS)
 		dlci->modem_tx |= TIOCM_DTR;
 	dlci->throttled = 0;
@@ -3098,6 +3136,8 @@ static int gsmtty_break_ctl(struct tty_struct *tty, int state)
 {
 	struct gsm_dlci *dlci = tty->driver_data;
 	int encode = 0;	/* Off */
+	if (dlci->state == DLCI_CLOSED)
+		return -EINVAL;
 
 	if (state == -1)	/* "On indefinitely" - we can't encode this
 				    properly */
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index 19083efa231..05e72bea9b0 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -49,6 +49,7 @@
 #include <linux/file.h>
 #include <linux/uaccess.h>
 #include <linux/module.h>
+#include <linux/ratelimit.h>
 
 
 /* number of characters left in xmit buffer before select has we have room */
@@ -100,7 +101,7 @@ struct n_tty_data {
 	struct mutex atomic_read_lock;
 	struct mutex output_lock;
 	struct mutex echo_lock;
-	spinlock_t read_lock;
+	raw_spinlock_t read_lock;
 };
 
 static inline int tty_put_user(struct tty_struct *tty, unsigned char x,
@@ -182,9 +183,9 @@ static void put_tty_queue(unsigned char c, struct n_tty_data *ldata)
 	 *	The problem of stomping on the buffers ends here.
 	 *	Why didn't anyone see this one coming? --AJK
 	*/
-	spin_lock_irqsave(&ldata->read_lock, flags);
+	raw_spin_lock_irqsave(&ldata->read_lock, flags);
 	put_tty_queue_nolock(c, ldata);
-	spin_unlock_irqrestore(&ldata->read_lock, flags);
+	raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 }
 
 /**
@@ -218,9 +219,9 @@ static void reset_buffer_flags(struct tty_struct *tty)
 	struct n_tty_data *ldata = tty->disc_data;
 	unsigned long flags;
 
-	spin_lock_irqsave(&ldata->read_lock, flags);
+	raw_spin_lock_irqsave(&ldata->read_lock, flags);
 	ldata->read_head = ldata->read_tail = ldata->read_cnt = 0;
-	spin_unlock_irqrestore(&ldata->read_lock, flags);
+	raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 
 	mutex_lock(&ldata->echo_lock);
 	ldata->echo_pos = ldata->echo_cnt = ldata->echo_overrun = 0;
@@ -276,7 +277,7 @@ static ssize_t n_tty_chars_in_buffer(struct tty_struct *tty)
 	unsigned long flags;
 	ssize_t n = 0;
 
-	spin_lock_irqsave(&ldata->read_lock, flags);
+	raw_spin_lock_irqsave(&ldata->read_lock, flags);
 	if (!ldata->icanon) {
 		n = ldata->read_cnt;
 	} else if (ldata->canon_data) {
@@ -284,7 +285,7 @@ static ssize_t n_tty_chars_in_buffer(struct tty_struct *tty)
 			ldata->canon_head - ldata->read_tail :
 			ldata->canon_head + (N_TTY_BUF_SIZE - ldata->read_tail);
 	}
-	spin_unlock_irqrestore(&ldata->read_lock, flags);
+	raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 	return n;
 }
 
@@ -915,19 +916,19 @@ static void eraser(unsigned char c, struct tty_struct *tty)
 		kill_type = WERASE;
 	else {
 		if (!L_ECHO(tty)) {
-			spin_lock_irqsave(&ldata->read_lock, flags);
+			raw_spin_lock_irqsave(&ldata->read_lock, flags);
 			ldata->read_cnt -= ((ldata->read_head - ldata->canon_head) &
 					  (N_TTY_BUF_SIZE - 1));
 			ldata->read_head = ldata->canon_head;
-			spin_unlock_irqrestore(&ldata->read_lock, flags);
+			raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 			return;
 		}
 		if (!L_ECHOK(tty) || !L_ECHOKE(tty) || !L_ECHOE(tty)) {
-			spin_lock_irqsave(&ldata->read_lock, flags);
+			raw_spin_lock_irqsave(&ldata->read_lock, flags);
 			ldata->read_cnt -= ((ldata->read_head - ldata->canon_head) &
 					  (N_TTY_BUF_SIZE - 1));
 			ldata->read_head = ldata->canon_head;
-			spin_unlock_irqrestore(&ldata->read_lock, flags);
+			raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 			finish_erasing(ldata);
 			echo_char(KILL_CHAR(tty), tty);
 			/* Add a newline if ECHOK is on and ECHOKE is off. */
@@ -961,10 +962,10 @@ static void eraser(unsigned char c, struct tty_struct *tty)
 				break;
 		}
 		cnt = (ldata->read_head - head) & (N_TTY_BUF_SIZE-1);
-		spin_lock_irqsave(&ldata->read_lock, flags);
+		raw_spin_lock_irqsave(&ldata->read_lock, flags);
 		ldata->read_head = head;
 		ldata->read_cnt -= cnt;
-		spin_unlock_irqrestore(&ldata->read_lock, flags);
+		raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 		if (L_ECHO(tty)) {
 			if (L_ECHOPRT(tty)) {
 				if (!ldata->erasing) {
@@ -1344,12 +1345,12 @@ send_signal:
 				put_tty_queue(c, ldata);
 
 handle_newline:
-			spin_lock_irqsave(&ldata->read_lock, flags);
+			raw_spin_lock_irqsave(&ldata->read_lock, flags);
 			set_bit(ldata->read_head, ldata->read_flags);
 			put_tty_queue_nolock(c, ldata);
 			ldata->canon_head = ldata->read_head;
 			ldata->canon_data++;
-			spin_unlock_irqrestore(&ldata->read_lock, flags);
+			raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 			kill_fasync(&tty->fasync, SIGIO, POLL_IN);
 			if (waitqueue_active(&tty->read_wait))
 				wake_up_interruptible(&tty->read_wait);
@@ -1423,7 +1424,7 @@ static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp,
 	unsigned long cpuflags;
 
 	if (ldata->real_raw) {
-		spin_lock_irqsave(&ldata->read_lock, cpuflags);
+		raw_spin_lock_irqsave(&ldata->read_lock, cpuflags);
 		i = min(N_TTY_BUF_SIZE - ldata->read_cnt,
 			N_TTY_BUF_SIZE - ldata->read_head);
 		i = min(count, i);
@@ -1439,7 +1440,7 @@ static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp,
 		memcpy(ldata->read_buf + ldata->read_head, cp, i);
 		ldata->read_head = (ldata->read_head + i) & (N_TTY_BUF_SIZE-1);
 		ldata->read_cnt += i;
-		spin_unlock_irqrestore(&ldata->read_lock, cpuflags);
+		raw_spin_unlock_irqrestore(&ldata->read_lock, cpuflags);
 	} else {
 		for (i = count, p = cp, f = fp; i; i--, p++) {
 			if (f)
@@ -1635,7 +1636,7 @@ static int n_tty_open(struct tty_struct *tty)
 	mutex_init(&ldata->atomic_read_lock);
 	mutex_init(&ldata->output_lock);
 	mutex_init(&ldata->echo_lock);
-	spin_lock_init(&ldata->read_lock);
+	raw_spin_lock_init(&ldata->read_lock);
 
 	/* These are ugly. Currently a malloc failure here can panic */
 	ldata->read_buf = kzalloc(N_TTY_BUF_SIZE, GFP_KERNEL);
@@ -1703,10 +1704,10 @@ static int copy_from_read_buf(struct tty_struct *tty,
 	bool is_eof;
 
 	retval = 0;
-	spin_lock_irqsave(&ldata->read_lock, flags);
+	raw_spin_lock_irqsave(&ldata->read_lock, flags);
 	n = min(ldata->read_cnt, N_TTY_BUF_SIZE - ldata->read_tail);
 	n = min(*nr, n);
-	spin_unlock_irqrestore(&ldata->read_lock, flags);
+	raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 	if (n) {
 		retval = copy_to_user(*b, &ldata->read_buf[ldata->read_tail], n);
 		n -= retval;
@@ -1714,13 +1715,13 @@ static int copy_from_read_buf(struct tty_struct *tty,
 			ldata->read_buf[ldata->read_tail] == EOF_CHAR(tty);
 		tty_audit_add_data(tty, &ldata->read_buf[ldata->read_tail], n,
 				ldata->icanon);
-		spin_lock_irqsave(&ldata->read_lock, flags);
+		raw_spin_lock_irqsave(&ldata->read_lock, flags);
 		ldata->read_tail = (ldata->read_tail + n) & (N_TTY_BUF_SIZE-1);
 		ldata->read_cnt -= n;
 		/* Turn single EOF into zero-length read */
 		if (L_EXTPROC(tty) && ldata->icanon && is_eof && !ldata->read_cnt)
 			n = 0;
-		spin_unlock_irqrestore(&ldata->read_lock, flags);
+		raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 		*b += n;
 		*nr -= n;
 	}
@@ -1900,7 +1901,7 @@ do_it_again:
 
 		if (ldata->icanon && !L_EXTPROC(tty)) {
 			/* N.B. avoid overrun if nr == 0 */
-			spin_lock_irqsave(&ldata->read_lock, flags);
+			raw_spin_lock_irqsave(&ldata->read_lock, flags);
 			while (nr && ldata->read_cnt) {
 				int eol;
 
@@ -1918,25 +1919,25 @@ do_it_again:
 					if (--ldata->canon_data < 0)
 						ldata->canon_data = 0;
 				}
-				spin_unlock_irqrestore(&ldata->read_lock, flags);
+				raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 
 				if (!eol || (c != __DISABLED_CHAR)) {
 					if (tty_put_user(tty, c, b++)) {
 						retval = -EFAULT;
 						b--;
-						spin_lock_irqsave(&ldata->read_lock, flags);
+						raw_spin_lock_irqsave(&ldata->read_lock, flags);
 						break;
 					}
 					nr--;
 				}
 				if (eol) {
 					tty_audit_push(tty);
-					spin_lock_irqsave(&ldata->read_lock, flags);
+					raw_spin_lock_irqsave(&ldata->read_lock, flags);
 					break;
 				}
-				spin_lock_irqsave(&ldata->read_lock, flags);
+				raw_spin_lock_irqsave(&ldata->read_lock, flags);
 			}
-			spin_unlock_irqrestore(&ldata->read_lock, flags);
+			raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 			if (retval)
 				break;
 		} else {
@@ -2188,7 +2189,7 @@ struct tty_ldisc_ops tty_ldisc_N_TTY = {
  *	n_tty_inherit_ops	-	inherit N_TTY methods
  *	@ops: struct tty_ldisc_ops where to save N_TTY methods
  *
- *	Used by a generic struct tty_ldisc_ops to easily inherit N_TTY
+ *	Enables a 'subclass' line discipline to 'inherit' N_TTY
  *	methods.
  */
 
diff --git a/drivers/tty/nozomi.c b/drivers/tty/nozomi.c
index a0c69ab0439..2dff1979615 100644
--- a/drivers/tty/nozomi.c
+++ b/drivers/tty/nozomi.c
@@ -827,15 +827,10 @@ static int receive_data(enum port_type index, struct nozomi *dc)
 	struct tty_struct *tty = tty_port_tty_get(&port->port);
 	int i, ret;
 
-	if (unlikely(!tty)) {
-		DBG1("tty not open for port: %d?", index);
-		return 1;
-	}
-
 	read_mem32((u32 *) &size, addr, 4);
 	/*  DBG1( "%d bytes port: %d", size, index); */
 
-	if (test_bit(TTY_THROTTLED, &tty->flags)) {
+	if (tty && test_bit(TTY_THROTTLED, &tty->flags)) {
 		DBG1("No room in tty, don't read data, don't ack interrupt, "
 			"disable interrupt");
 
@@ -855,13 +850,14 @@ static int receive_data(enum port_type index, struct nozomi *dc)
 		read_mem32((u32 *) buf, addr + offset, RECEIVE_BUF_MAX);
 
 		if (size == 1) {
-			tty_insert_flip_char(tty, buf[0], TTY_NORMAL);
+			tty_insert_flip_char(&port->port, buf[0], TTY_NORMAL);
 			size = 0;
 		} else if (size < RECEIVE_BUF_MAX) {
-			size -= tty_insert_flip_string(tty, (char *) buf, size);
+			size -= tty_insert_flip_string(&port->port,
+					(char *)buf, size);
 		} else {
-			i = tty_insert_flip_string(tty, \
-						(char *) buf, RECEIVE_BUF_MAX);
+			i = tty_insert_flip_string(&port->port,
+					(char *)buf, RECEIVE_BUF_MAX);
 			size -= i;
 			offset += i;
 		}
@@ -1276,15 +1272,11 @@ static irqreturn_t interrupt_handler(int irq, void *dev_id)
 
 exit_handler:
 	spin_unlock(&dc->spin_mutex);
-	for (a = 0; a < NOZOMI_MAX_PORTS; a++) {
-		struct tty_struct *tty;
-		if (test_and_clear_bit(a, &dc->flip)) {
-			tty = tty_port_tty_get(&dc->port[a].port);
-			if (tty)
-				tty_flip_buffer_push(tty);
-			tty_kref_put(tty);
-		}
-	}
+
+	for (a = 0; a < NOZOMI_MAX_PORTS; a++)
+		if (test_and_clear_bit(a, &dc->flip))
+			tty_flip_buffer_push(&dc->port[a].port);
+
 	return IRQ_HANDLED;
 none:
 	spin_unlock(&dc->spin_mutex);
@@ -1687,12 +1679,6 @@ static int ntty_write(struct tty_struct *tty, const unsigned char *buffer,
 
 	rval = kfifo_in(&port->fifo_ul, (unsigned char *)buffer, count);
 
-	/* notify card */
-	if (unlikely(dc == NULL)) {
-		DBG1("No device context?");
-		goto exit;
-	}
-
 	spin_lock_irqsave(&dc->spin_mutex, flags);
 	/* CTS is only valid on the modem channel */
 	if (port == &(dc->port[PORT_MDM])) {
@@ -1708,7 +1694,6 @@ static int ntty_write(struct tty_struct *tty, const unsigned char *buffer,
 	}
 	spin_unlock_irqrestore(&dc->spin_mutex, flags);
 
-exit:
 	return rval;
 }
 
diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index 79ff3a5e925..c24b4db243b 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -38,16 +38,18 @@ static void pty_close(struct tty_struct *tty, struct file *filp)
 	if (tty->driver->subtype == PTY_TYPE_MASTER)
 		WARN_ON(tty->count > 1);
 	else {
+		if (test_bit(TTY_IO_ERROR, &tty->flags))
+			return;
 		if (tty->count > 2)
 			return;
 	}
+	set_bit(TTY_IO_ERROR, &tty->flags);
 	wake_up_interruptible(&tty->read_wait);
 	wake_up_interruptible(&tty->write_wait);
 	tty->packet = 0;
 	/* Review - krefs on tty_link ?? */
 	if (!tty->link)
 		return;
-	tty->link->packet = 0;
 	set_bit(TTY_OTHER_CLOSED, &tty->link->flags);
 	wake_up_interruptible(&tty->link->read_wait);
 	wake_up_interruptible(&tty->link->write_wait);
@@ -55,9 +57,10 @@ static void pty_close(struct tty_struct *tty, struct file *filp)
 		set_bit(TTY_OTHER_CLOSED, &tty->flags);
 #ifdef CONFIG_UNIX98_PTYS
 		if (tty->driver == ptm_driver) {
-		        mutex_lock(&devpts_mutex);
-			devpts_pty_kill(tty->link->driver_data);
-		        mutex_unlock(&devpts_mutex);
+			mutex_lock(&devpts_mutex);
+			if (tty->link->driver_data)
+				devpts_pty_kill(tty->link->driver_data);
+			mutex_unlock(&devpts_mutex);
 		}
 #endif
 		tty_unlock(tty);
@@ -120,10 +123,10 @@ static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c)
 
 	if (c > 0) {
 		/* Stuff the data into the input queue of the other end */
-		c = tty_insert_flip_string(to, buf, c);
+		c = tty_insert_flip_string(to->port, buf, c);
 		/* And shovel */
 		if (c) {
-			tty_flip_buffer_push(to);
+			tty_flip_buffer_push(to->port);
 			tty_wakeup(tty);
 		}
 	}
@@ -246,14 +249,17 @@ static int pty_open(struct tty_struct *tty, struct file *filp)
 	if (!tty || !tty->link)
 		goto out;
 
+	set_bit(TTY_IO_ERROR, &tty->flags);
+
 	retval = -EIO;
 	if (test_bit(TTY_OTHER_CLOSED, &tty->flags))
 		goto out;
 	if (test_bit(TTY_PTY_LOCK, &tty->link->flags))
 		goto out;
-	if (tty->link->count != 1)
+	if (tty->driver->subtype == PTY_TYPE_SLAVE && tty->link->count != 1)
 		goto out;
 
+	clear_bit(TTY_IO_ERROR, &tty->flags);
 	clear_bit(TTY_OTHER_CLOSED, &tty->link->flags);
 	set_bit(TTY_THROTTLED, &tty->flags);
 	retval = 0;
@@ -663,7 +669,7 @@ static const struct tty_operations pty_unix98_ops = {
  *	Allocate a unix98 pty master device from the ptmx driver.
  *
  *	Locking: tty_mutex protects the init_dev work. tty->count should
- * 		protect the rest.
+ *		protect the rest.
  *		allocated_ptys_lock handles the list of free pty numbers
  */
 
@@ -704,6 +710,7 @@ static int ptmx_open(struct inode *inode, struct file *filp)
 	mutex_unlock(&tty_mutex);
 
 	set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
+	tty->driver_data = inode;
 
 	tty_add_file(tty, filp);
 
@@ -714,14 +721,13 @@ static int ptmx_open(struct inode *inode, struct file *filp)
 		retval = PTR_ERR(slave_inode);
 		goto err_release;
 	}
+	tty->link->driver_data = slave_inode;
 
 	retval = ptm_driver->ops->open(tty, filp);
 	if (retval)
 		goto err_release;
 
 	tty_unlock(tty);
-	tty->driver_data = inode;
-	tty->link->driver_data = slave_inode;
 	return 0;
 err_release:
 	tty_unlock(tty);
@@ -797,7 +803,7 @@ static void __init unix98_pty_init(void)
 	cdev_init(&ptmx_cdev, &ptmx_fops);
 	if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
 	    register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
-		panic("Couldn't register /dev/ptmx driver\n");
+		panic("Couldn't register /dev/ptmx driver");
 	device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
 }
 
diff --git a/drivers/tty/rocket.c b/drivers/tty/rocket.c
index e42009a0052..1d270034bfc 100644
--- a/drivers/tty/rocket.c
+++ b/drivers/tty/rocket.c
@@ -55,7 +55,7 @@
 #undef REV_PCI_ORDER
 #undef ROCKET_DEBUG_IO
 
-#define POLL_PERIOD HZ/100	/*  Polling period .01 seconds (10ms) */
+#define POLL_PERIOD (HZ/100)	/*  Polling period .01 seconds (10ms) */
 
 /****** Kernel includes ******/
 
@@ -315,9 +315,8 @@ static inline int rocket_paranoia_check(struct r_port *info,
  *  that receive data is present on a serial port.  Pulls data from FIFO, moves it into the 
  *  tty layer.  
  */
-static void rp_do_receive(struct r_port *info,
-			  struct tty_struct *tty,
-			  CHANNEL_t * cp, unsigned int ChanStatus)
+static void rp_do_receive(struct r_port *info, CHANNEL_t *cp,
+		unsigned int ChanStatus)
 {
 	unsigned int CharNStat;
 	int ToRecv, wRecv, space;
@@ -379,7 +378,8 @@ static void rp_do_receive(struct r_port *info,
 				flag = TTY_OVERRUN;
 			else
 				flag = TTY_NORMAL;
-			tty_insert_flip_char(tty, CharNStat & 0xff, flag);
+			tty_insert_flip_char(&info->port, CharNStat & 0xff,
+					flag);
 			ToRecv--;
 		}
 
@@ -399,7 +399,7 @@ static void rp_do_receive(struct r_port *info,
 		 * characters at time by doing repeated word IO
 		 * transfer.
 		 */
-		space = tty_prepare_flip_string(tty, &cbuf, ToRecv);
+		space = tty_prepare_flip_string(&info->port, &cbuf, ToRecv);
 		if (space < ToRecv) {
 #ifdef ROCKET_DEBUG_RECEIVE
 			printk(KERN_INFO "rp_do_receive:insufficient space ToRecv=%d space=%d\n", ToRecv, space);
@@ -415,7 +415,7 @@ static void rp_do_receive(struct r_port *info,
 			cbuf[ToRecv - 1] = sInB(sGetTxRxDataIO(cp));
 	}
 	/*  Push the data up to the tty layer */
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&info->port);
 }
 
 /*
@@ -494,7 +494,6 @@ static void rp_do_transmit(struct r_port *info)
 static void rp_handle_port(struct r_port *info)
 {
 	CHANNEL_t *cp;
-	struct tty_struct *tty;
 	unsigned int IntMask, ChanStatus;
 
 	if (!info)
@@ -505,12 +504,7 @@ static void rp_handle_port(struct r_port *info)
 				"info->flags & NOT_INIT\n");
 		return;
 	}
-	tty = tty_port_tty_get(&info->port);
-	if (!tty) {
-		printk(KERN_WARNING "rp: WARNING: rp_handle_port called with "
-				"tty==NULL\n");
-		return;
-	}
+
 	cp = &info->channel;
 
 	IntMask = sGetChanIntID(cp) & info->intmask;
@@ -519,7 +513,7 @@ static void rp_handle_port(struct r_port *info)
 #endif
 	ChanStatus = sGetChanStatus(cp);
 	if (IntMask & RXF_TRIG) {	/* Rx FIFO trigger level */
-		rp_do_receive(info, tty, cp, ChanStatus);
+		rp_do_receive(info, cp, ChanStatus);
 	}
 	if (IntMask & DELTA_CD) {	/* CD change  */
 #if (defined(ROCKET_DEBUG_OPEN) || defined(ROCKET_DEBUG_INTR) || defined(ROCKET_DEBUG_HANGUP))
@@ -527,10 +521,15 @@ static void rp_handle_port(struct r_port *info)
 		       (ChanStatus & CD_ACT) ? "on" : "off");
 #endif
 		if (!(ChanStatus & CD_ACT) && info->cd_status) {
+			struct tty_struct *tty;
 #ifdef ROCKET_DEBUG_HANGUP
 			printk(KERN_INFO "CD drop, calling hangup.\n");
 #endif
-			tty_hangup(tty);
+			tty = tty_port_tty_get(&info->port);
+			if (tty) {
+				tty_hangup(tty);
+				tty_kref_put(tty);
+			}
 		}
 		info->cd_status = (ChanStatus & CD_ACT) ? 1 : 0;
 		wake_up_interruptible(&info->port.open_wait);
@@ -543,7 +542,6 @@ static void rp_handle_port(struct r_port *info)
 		printk(KERN_INFO "DSR change...\n");
 	}
 #endif
-	tty_kref_put(tty);
 }
 
 /*
@@ -1758,8 +1756,29 @@ static void rp_flush_buffer(struct tty_struct *tty)
 
 #ifdef CONFIG_PCI
 
-static struct pci_device_id __used rocket_pci_ids[] = {
-	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_ANY_ID) },
+static DEFINE_PCI_DEVICE_TABLE(rocket_pci_ids) = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_RP4QUAD) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_RP8OCTA) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_URP8OCTA) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_RP8INTF) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_URP8INTF) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_RP8J) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_RP4J) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_RP8SNI) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_RP16SNI) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_RP16INTF) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_URP16INTF) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_CRP16INTF) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_RP32INTF) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_URP32INTF) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_RPP4) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_RPP8) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_RP2_232) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_RP2_422) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_RP6M) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_RP4M) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_UPCI_RM3_8PORT) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_RP, PCI_DEVICE_ID_UPCI_RM3_4PORT) },
 	{ }
 };
 MODULE_DEVICE_TABLE(pci, rocket_pci_ids);
@@ -1781,7 +1800,8 @@ static __init int register_PCI(int i, struct pci_dev *dev)
 	WordIO_t ConfigIO = 0;
 	ByteIO_t UPCIRingInd = 0;
 
-	if (!dev || pci_enable_device(dev))
+	if (!dev || !pci_match_id(rocket_pci_ids, dev) ||
+	    pci_enable_device(dev))
 		return 0;
 
 	rcktpt_io_addr[i] = pci_resource_start(dev, 0);
diff --git a/drivers/tty/serial/21285.c b/drivers/tty/serial/21285.c
index a44345a2dbb..c7e8b60b617 100644
--- a/drivers/tty/serial/21285.c
+++ b/drivers/tty/serial/21285.c
@@ -85,7 +85,6 @@ static void serial21285_enable_ms(struct uart_port *port)
 static irqreturn_t serial21285_rx_chars(int irq, void *dev_id)
 {
 	struct uart_port *port = dev_id;
-	struct tty_struct *tty = port->state->port.tty;
 	unsigned int status, ch, flag, rxs, max_count = 256;
 
 	status = *CSR_UARTFLG;
@@ -115,7 +114,7 @@ static irqreturn_t serial21285_rx_chars(int irq, void *dev_id)
 
 		status = *CSR_UARTFLG;
 	}
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&port->state->port);
 
 	return IRQ_HANDLED;
 }
diff --git a/drivers/tty/serial/68328serial.c b/drivers/tty/serial/68328serial.c
index f99a84526f8..49399470794 100644
--- a/drivers/tty/serial/68328serial.c
+++ b/drivers/tty/serial/68328serial.c
@@ -262,8 +262,7 @@ static void rs_start(struct tty_struct *tty)
 	local_irq_restore(flags);
 }
 
-static void receive_chars(struct m68k_serial *info, struct tty_struct *tty,
-		unsigned short rx)
+static void receive_chars(struct m68k_serial *info, unsigned short rx)
 {
 	m68328_uart *uart = &uart_addr[info->line];
 	unsigned char ch, flag;
@@ -293,9 +292,6 @@ static void receive_chars(struct m68k_serial *info, struct tty_struct *tty,
 			}
 		}
 
-		if(!tty)
-			goto clear_and_exit;
-		
 		flag = TTY_NORMAL;
 
 		if (rx & URX_PARITY_ERROR)
@@ -305,15 +301,12 @@ static void receive_chars(struct m68k_serial *info, struct tty_struct *tty,
 		else if (rx & URX_FRAME_ERROR)
 			flag = TTY_FRAME;
 
-		tty_insert_flip_char(tty, ch, flag);
+		tty_insert_flip_char(&info->tport, ch, flag);
 #ifndef CONFIG_XCOPILOT_BUGS
 	} while((rx = uart->urx.w) & URX_DATA_READY);
 #endif
 
-	tty_schedule_flip(tty);
-
-clear_and_exit:
-	return;
+	tty_schedule_flip(&info->tport);
 }
 
 static void transmit_chars(struct m68k_serial *info, struct tty_struct *tty)
@@ -367,11 +360,11 @@ irqreturn_t rs_interrupt(int irq, void *dev_id)
 	tx = uart->utx.w;
 
 	if (rx & URX_DATA_READY)
-		receive_chars(info, tty, rx);
+		receive_chars(info, rx);
 	if (tx & UTX_TX_AVAIL)
 		transmit_chars(info, tty);
 #else
-	receive_chars(info, tty, rx);
+	receive_chars(info, rx);
 #endif
 	tty_kref_put(tty);
 
@@ -1009,7 +1002,7 @@ static void rs_close(struct tty_struct *tty, struct file * filp)
 	m68328_uart *uart = &uart_addr[info->line];
 	unsigned long flags;
 
-	if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
+	if (serial_paranoia_check(info, tty->name, "rs_close"))
 		return;
 	
 	local_irq_save(flags);
diff --git a/drivers/tty/serial/8250/8250.c b/drivers/tty/serial/8250/8250.c
index f9320437a64..0efc815a496 100644
--- a/drivers/tty/serial/8250/8250.c
+++ b/drivers/tty/serial/8250/8250.c
@@ -239,13 +239,6 @@ static const struct serial8250_config uart_config[] = {
 		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
 		.flags		= UART_CAP_FIFO | UART_CAP_UUE | UART_CAP_RTOIE,
 	},
-	[PORT_RM9000] = {
-		.name		= "RM9000",
-		.fifo_size	= 16,
-		.tx_loadsz	= 16,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
-		.flags		= UART_CAP_FIFO,
-	},
 	[PORT_OCTEON] = {
 		.name		= "OCTEON",
 		.fifo_size	= 64,
@@ -324,9 +317,9 @@ static void default_serial_dl_write(struct uart_8250_port *up, int value)
 	serial_out(up, UART_DLM, value >> 8 & 0xff);
 }
 
-#ifdef CONFIG_MIPS_ALCHEMY
+#if defined(CONFIG_MIPS_ALCHEMY) || defined(CONFIG_SERIAL_8250_RT288X)
 
-/* Au1x00 UART hardware has a weird register layout */
+/* Au1x00/RT288x UART hardware has a weird register layout */
 static const u8 au_io_in_map[] = {
 	[UART_RX]  = 0,
 	[UART_IER] = 2,
@@ -370,56 +363,6 @@ static void au_serial_dl_write(struct uart_8250_port *up, int value)
 
 #endif
 
-#ifdef CONFIG_SERIAL_8250_RM9K
-
-static const u8
-	regmap_in[8] = {
-		[UART_RX]	= 0x00,
-		[UART_IER]	= 0x0c,
-		[UART_IIR]	= 0x14,
-		[UART_LCR]	= 0x1c,
-		[UART_MCR]	= 0x20,
-		[UART_LSR]	= 0x24,
-		[UART_MSR]	= 0x28,
-		[UART_SCR]	= 0x2c
-	},
-	regmap_out[8] = {
-		[UART_TX] 	= 0x04,
-		[UART_IER]	= 0x0c,
-		[UART_FCR]	= 0x18,
-		[UART_LCR]	= 0x1c,
-		[UART_MCR]	= 0x20,
-		[UART_LSR]	= 0x24,
-		[UART_MSR]	= 0x28,
-		[UART_SCR]	= 0x2c
-	};
-
-static unsigned int rm9k_serial_in(struct uart_port *p, int offset)
-{
-	offset = regmap_in[offset] << p->regshift;
-	return readl(p->membase + offset);
-}
-
-static void rm9k_serial_out(struct uart_port *p, int offset, int value)
-{
-	offset = regmap_out[offset] << p->regshift;
-	writel(value, p->membase + offset);
-}
-
-static int rm9k_serial_dl_read(struct uart_8250_port *up)
-{
-	return ((__raw_readl(up->port.membase + 0x10) << 8) |
-		(__raw_readl(up->port.membase + 0x08) & 0xff)) & 0xffff;
-}
-
-static void rm9k_serial_dl_write(struct uart_8250_port *up, int value)
-{
-	__raw_writel(value, up->port.membase + 0x08);
-	__raw_writel(value >> 8, up->port.membase + 0x10);
-}
-
-#endif
-
 static unsigned int hub6_serial_in(struct uart_port *p, int offset)
 {
 	offset = offset << p->regshift;
@@ -497,16 +440,7 @@ static void set_io_from_upio(struct uart_port *p)
 		p->serial_out = mem32_serial_out;
 		break;
 
-#ifdef CONFIG_SERIAL_8250_RM9K
-	case UPIO_RM9000:
-		p->serial_in = rm9k_serial_in;
-		p->serial_out = rm9k_serial_out;
-		up->dl_read = rm9k_serial_dl_read;
-		up->dl_write = rm9k_serial_dl_write;
-		break;
-#endif
-
-#ifdef CONFIG_MIPS_ALCHEMY
+#if defined(CONFIG_MIPS_ALCHEMY) || defined(CONFIG_SERIAL_8250_RT288X)
 	case UPIO_AU:
 		p->serial_in = au_serial_in;
 		p->serial_out = au_serial_out;
@@ -1341,7 +1275,9 @@ static void serial8250_start_tx(struct uart_port *port)
 	struct uart_8250_port *up =
 		container_of(port, struct uart_8250_port, port);
 
-	if (!(up->ier & UART_IER_THRI)) {
+	if (up->dma && !serial8250_tx_dma(up)) {
+		return;
+	} else if (!(up->ier & UART_IER_THRI)) {
 		up->ier |= UART_IER_THRI;
 		serial_port_out(port, UART_IER, up->ier);
 
@@ -1349,9 +1285,7 @@ static void serial8250_start_tx(struct uart_port *port)
 			unsigned char lsr;
 			lsr = serial_in(up, UART_LSR);
 			up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS;
-			if ((port->type == PORT_RM9000) ?
-				(lsr & UART_LSR_THRE) :
-				(lsr & UART_LSR_TEMT))
+			if (lsr & UART_LSR_TEMT)
 				serial8250_tx_chars(up);
 		}
 	}
@@ -1397,7 +1331,6 @@ unsigned char
 serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr)
 {
 	struct uart_port *port = &up->port;
-	struct tty_struct *tty = port->state->port.tty;
 	unsigned char ch;
 	int max_count = 256;
 	char flag;
@@ -1462,7 +1395,7 @@ ignore_char:
 		lsr = serial_in(up, UART_LSR);
 	} while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (max_count-- > 0));
 	spin_unlock(&port->lock);
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&port->state->port);
 	spin_lock(&port->lock);
 	return lsr;
 }
@@ -1547,6 +1480,7 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir)
 	unsigned long flags;
 	struct uart_8250_port *up =
 		container_of(port, struct uart_8250_port, port);
+	int dma_err = 0;
 
 	if (iir & UART_IIR_NO_INT)
 		return 0;
@@ -1557,8 +1491,13 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir)
 
 	DEBUG_INTR("status = %x...", status);
 
-	if (status & (UART_LSR_DR | UART_LSR_BI))
-		status = serial8250_rx_chars(up, status);
+	if (status & (UART_LSR_DR | UART_LSR_BI)) {
+		if (up->dma)
+			dma_err = serial8250_rx_dma(up, iir);
+
+		if (!up->dma || dma_err)
+			status = serial8250_rx_chars(up, status);
+	}
 	serial8250_modem_status(up);
 	if (status & UART_LSR_THRE)
 		serial8250_tx_chars(up);
@@ -1991,9 +1930,12 @@ static int serial8250_startup(struct uart_port *port)
 	if (port->type == PORT_8250_CIR)
 		return -ENODEV;
 
-	port->fifosize = uart_config[up->port.type].fifo_size;
-	up->tx_loadsz = uart_config[up->port.type].tx_loadsz;
-	up->capabilities = uart_config[up->port.type].flags;
+	if (!port->fifosize)
+		port->fifosize = uart_config[port->type].fifo_size;
+	if (!up->tx_loadsz)
+		up->tx_loadsz = uart_config[port->type].tx_loadsz;
+	if (!up->capabilities)
+		up->capabilities = uart_config[port->type].flags;
 	up->mcr = 0;
 
 	if (port->iotype != up->cur_iotype)
@@ -2198,6 +2140,18 @@ dont_test_tx_en:
 	up->msr_saved_flags = 0;
 
 	/*
+	 * Request DMA channels for both RX and TX.
+	 */
+	if (up->dma) {
+		retval = serial8250_request_dma(up);
+		if (retval) {
+			pr_warn_ratelimited("ttyS%d - failed to request DMA\n",
+					    serial_index(port));
+			up->dma = NULL;
+		}
+	}
+
+	/*
 	 * Finally, enable interrupts.  Note: Modem status interrupts
 	 * are set via set_termios(), which will be occurring imminently
 	 * anyway, so we don't enable them here.
@@ -2230,6 +2184,9 @@ static void serial8250_shutdown(struct uart_port *port)
 	up->ier = 0;
 	serial_port_out(port, UART_IER, 0);
 
+	if (up->dma)
+		serial8250_release_dma(up);
+
 	spin_lock_irqsave(&port->lock, flags);
 	if (port->flags & UPF_FOURPORT) {
 		/* reset interrupts on the AST Fourport board */
@@ -2826,9 +2783,12 @@ static void
 serial8250_init_fixed_type_port(struct uart_8250_port *up, unsigned int type)
 {
 	up->port.type = type;
-	up->port.fifosize = uart_config[type].fifo_size;
-	up->capabilities = uart_config[type].flags;
-	up->tx_loadsz = uart_config[type].tx_loadsz;
+	if (!up->port.fifosize)
+		up->port.fifosize = uart_config[type].fifo_size;
+	if (!up->tx_loadsz)
+		up->tx_loadsz = uart_config[type].tx_loadsz;
+	if (!up->capabilities)
+		up->capabilities = uart_config[type].flags;
 }
 
 static void __init
@@ -3262,6 +3222,10 @@ int serial8250_register_8250_port(struct uart_8250_port *up)
 		uart->bugs		= up->bugs;
 		uart->port.mapbase      = up->port.mapbase;
 		uart->port.private_data = up->port.private_data;
+		uart->port.fifosize	= up->port.fifosize;
+		uart->tx_loadsz		= up->tx_loadsz;
+		uart->capabilities	= up->capabilities;
+
 		if (up->port.dev)
 			uart->port.dev = up->port.dev;
 
@@ -3287,6 +3251,8 @@ int serial8250_register_8250_port(struct uart_8250_port *up)
 			uart->dl_read = up->dl_read;
 		if (up->dl_write)
 			uart->dl_write = up->dl_write;
+		if (up->dma)
+			uart->dma = up->dma;
 
 		if (serial8250_isa_config != NULL)
 			serial8250_isa_config(0, &uart->port,
diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h
index 12caa1292b7..34eb676916f 100644
--- a/drivers/tty/serial/8250/8250.h
+++ b/drivers/tty/serial/8250/8250.h
@@ -12,6 +12,35 @@
  */
 
 #include <linux/serial_8250.h>
+#include <linux/dmaengine.h>
+
+struct uart_8250_dma {
+	dma_filter_fn		fn;
+	void			*rx_param;
+	void			*tx_param;
+
+	int			rx_chan_id;
+	int			tx_chan_id;
+
+	struct dma_slave_config	rxconf;
+	struct dma_slave_config	txconf;
+
+	struct dma_chan		*rxchan;
+	struct dma_chan		*txchan;
+
+	dma_addr_t		rx_addr;
+	dma_addr_t		tx_addr;
+
+	dma_cookie_t		rx_cookie;
+	dma_cookie_t		tx_cookie;
+
+	void			*rx_buf;
+
+	size_t			rx_size;
+	size_t			tx_size;
+
+	unsigned char		tx_running:1;
+};
 
 struct old_serial_port {
 	unsigned int uart;
@@ -143,3 +172,24 @@ static inline int is_omap1510_8250(struct uart_8250_port *pt)
 	return 0;
 }
 #endif
+
+#ifdef CONFIG_SERIAL_8250_DMA
+extern int serial8250_tx_dma(struct uart_8250_port *);
+extern int serial8250_rx_dma(struct uart_8250_port *, unsigned int iir);
+extern int serial8250_request_dma(struct uart_8250_port *);
+extern void serial8250_release_dma(struct uart_8250_port *);
+#else
+static inline int serial8250_tx_dma(struct uart_8250_port *p)
+{
+	return -1;
+}
+static inline int serial8250_rx_dma(struct uart_8250_port *p, unsigned int iir)
+{
+	return -1;
+}
+static inline int serial8250_request_dma(struct uart_8250_port *p)
+{
+	return -1;
+}
+static inline void serial8250_release_dma(struct uart_8250_port *p) { }
+#endif
diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c
new file mode 100644
index 00000000000..b9f7fd28112
--- /dev/null
+++ b/drivers/tty/serial/8250/8250_dma.c
@@ -0,0 +1,216 @@
+/*
+ * 8250_dma.c - DMA Engine API support for 8250.c
+ *
+ * Copyright (C) 2013 Intel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial_reg.h>
+#include <linux/dma-mapping.h>
+
+#include "8250.h"
+
+static void __dma_tx_complete(void *param)
+{
+	struct uart_8250_port	*p = param;
+	struct uart_8250_dma	*dma = p->dma;
+	struct circ_buf		*xmit = &p->port.state->xmit;
+
+	dma->tx_running = 0;
+
+	dma_sync_single_for_cpu(dma->txchan->device->dev, dma->tx_addr,
+				UART_XMIT_SIZE, DMA_TO_DEVICE);
+
+	xmit->tail += dma->tx_size;
+	xmit->tail &= UART_XMIT_SIZE - 1;
+	p->port.icount.tx += dma->tx_size;
+
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(&p->port);
+
+	if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) {
+		serial8250_tx_dma(p);
+		uart_write_wakeup(&p->port);
+	}
+}
+
+static void __dma_rx_complete(void *param)
+{
+	struct uart_8250_port	*p = param;
+	struct uart_8250_dma	*dma = p->dma;
+	struct tty_port		*tty_port = &p->port.state->port;
+	struct dma_tx_state	state;
+	int			count;
+
+	dma_sync_single_for_cpu(dma->rxchan->device->dev, dma->rx_addr,
+				dma->rx_size, DMA_FROM_DEVICE);
+
+	dmaengine_tx_status(dma->rxchan, dma->rx_cookie, &state);
+	dmaengine_terminate_all(dma->rxchan);
+
+	count = dma->rx_size - state.residue;
+
+	tty_insert_flip_string(tty_port, dma->rx_buf, count);
+	p->port.icount.rx += count;
+
+	tty_flip_buffer_push(tty_port);
+}
+
+int serial8250_tx_dma(struct uart_8250_port *p)
+{
+	struct uart_8250_dma		*dma = p->dma;
+	struct circ_buf			*xmit = &p->port.state->xmit;
+	struct dma_async_tx_descriptor	*desc;
+
+	if (dma->tx_running)
+		return -EBUSY;
+
+	dma->tx_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
+	if (!dma->tx_size)
+		return -EINVAL;
+
+	desc = dmaengine_prep_slave_single(dma->txchan,
+					   dma->tx_addr + xmit->tail,
+					   dma->tx_size, DMA_MEM_TO_DEV,
+					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+	if (!desc)
+		return -EBUSY;
+
+	dma->tx_running = 1;
+
+	desc->callback = __dma_tx_complete;
+	desc->callback_param = p;
+
+	dma->tx_cookie = dmaengine_submit(desc);
+
+	dma_sync_single_for_device(dma->txchan->device->dev, dma->tx_addr,
+				   UART_XMIT_SIZE, DMA_TO_DEVICE);
+
+	dma_async_issue_pending(dma->txchan);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(serial8250_tx_dma);
+
+int serial8250_rx_dma(struct uart_8250_port *p, unsigned int iir)
+{
+	struct uart_8250_dma		*dma = p->dma;
+	struct dma_async_tx_descriptor	*desc;
+	struct dma_tx_state		state;
+	int				dma_status;
+
+	/*
+	 * If RCVR FIFO trigger level was not reached, complete the transfer and
+	 * let 8250.c copy the remaining data.
+	 */
+	if ((iir & 0x3f) == UART_IIR_RX_TIMEOUT) {
+		dma_status = dmaengine_tx_status(dma->rxchan, dma->rx_cookie,
+						&state);
+		if (dma_status == DMA_IN_PROGRESS) {
+			dmaengine_pause(dma->rxchan);
+			__dma_rx_complete(p);
+		}
+		return -ETIMEDOUT;
+	}
+
+	desc = dmaengine_prep_slave_single(dma->rxchan, dma->rx_addr,
+					   dma->rx_size, DMA_DEV_TO_MEM,
+					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+	if (!desc)
+		return -EBUSY;
+
+	desc->callback = __dma_rx_complete;
+	desc->callback_param = p;
+
+	dma->rx_cookie = dmaengine_submit(desc);
+
+	dma_sync_single_for_device(dma->rxchan->device->dev, dma->rx_addr,
+				   dma->rx_size, DMA_FROM_DEVICE);
+
+	dma_async_issue_pending(dma->rxchan);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(serial8250_rx_dma);
+
+int serial8250_request_dma(struct uart_8250_port *p)
+{
+	struct uart_8250_dma	*dma = p->dma;
+	dma_cap_mask_t		mask;
+
+	dma->rxconf.src_addr = p->port.mapbase + UART_RX;
+	dma->txconf.dst_addr = p->port.mapbase + UART_TX;
+
+	dma_cap_zero(mask);
+	dma_cap_set(DMA_SLAVE, mask);
+
+	/* Get a channel for RX */
+	dma->rxchan = dma_request_channel(mask, dma->fn, dma->rx_param);
+	if (!dma->rxchan)
+		return -ENODEV;
+
+	dmaengine_slave_config(dma->rxchan, &dma->rxconf);
+
+	/* Get a channel for TX */
+	dma->txchan = dma_request_channel(mask, dma->fn, dma->tx_param);
+	if (!dma->txchan) {
+		dma_release_channel(dma->rxchan);
+		return -ENODEV;
+	}
+
+	dmaengine_slave_config(dma->txchan, &dma->txconf);
+
+	/* RX buffer */
+	if (!dma->rx_size)
+		dma->rx_size = PAGE_SIZE;
+
+	dma->rx_buf = dma_alloc_coherent(dma->rxchan->device->dev, dma->rx_size,
+					&dma->rx_addr, GFP_KERNEL);
+	if (!dma->rx_buf) {
+		dma_release_channel(dma->rxchan);
+		dma_release_channel(dma->txchan);
+		return -ENOMEM;
+	}
+
+	/* TX buffer */
+	dma->tx_addr = dma_map_single(dma->txchan->device->dev,
+					p->port.state->xmit.buf,
+					UART_XMIT_SIZE,
+					DMA_TO_DEVICE);
+
+	dev_dbg_ratelimited(p->port.dev, "got both dma channels\n");
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(serial8250_request_dma);
+
+void serial8250_release_dma(struct uart_8250_port *p)
+{
+	struct uart_8250_dma *dma = p->dma;
+
+	if (!dma)
+		return;
+
+	/* Release RX resources */
+	dmaengine_terminate_all(dma->rxchan);
+	dma_free_coherent(dma->rxchan->device->dev, dma->rx_size, dma->rx_buf,
+			  dma->rx_addr);
+	dma_release_channel(dma->rxchan);
+	dma->rxchan = NULL;
+
+	/* Release TX resources */
+	dmaengine_terminate_all(dma->txchan);
+	dma_unmap_single(dma->txchan->device->dev, dma->tx_addr,
+			 UART_XMIT_SIZE, DMA_TO_DEVICE);
+	dma_release_channel(dma->txchan);
+	dma->txchan = NULL;
+	dma->tx_running = 0;
+
+	dev_dbg_ratelimited(p->port.dev, "dma channels released\n");
+}
+EXPORT_SYMBOL_GPL(serial8250_release_dma);
diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 096d2ef48b3..db0e66f6dd0 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -2,6 +2,7 @@
  * Synopsys DesignWare 8250 driver.
  *
  * Copyright 2011 Picochip, Jamie Iles.
+ * Copyright 2013 Intel Corporation
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -24,6 +25,34 @@
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
+#include <linux/acpi.h>
+
+#include "8250.h"
+
+/* Offsets for the DesignWare specific registers */
+#define DW_UART_USR	0x1f /* UART Status Register */
+#define DW_UART_CPR	0xf4 /* Component Parameter Register */
+#define DW_UART_UCV	0xf8 /* UART Component Version */
+
+/* Intel Low Power Subsystem specific */
+#define LPSS_PRV_CLOCK_PARAMS 0x800
+
+/* Component Parameter Register bits */
+#define DW_UART_CPR_ABP_DATA_WIDTH	(3 << 0)
+#define DW_UART_CPR_AFCE_MODE		(1 << 4)
+#define DW_UART_CPR_THRE_MODE		(1 << 5)
+#define DW_UART_CPR_SIR_MODE		(1 << 6)
+#define DW_UART_CPR_SIR_LP_MODE		(1 << 7)
+#define DW_UART_CPR_ADDITIONAL_FEATURES	(1 << 8)
+#define DW_UART_CPR_FIFO_ACCESS		(1 << 9)
+#define DW_UART_CPR_FIFO_STAT		(1 << 10)
+#define DW_UART_CPR_SHADOW		(1 << 11)
+#define DW_UART_CPR_ENCODED_PARMS	(1 << 12)
+#define DW_UART_CPR_DMA_EXTRA		(1 << 13)
+#define DW_UART_CPR_FIFO_MODE		(0xff << 16)
+/* Helper for fifo size calculation */
+#define DW_UART_CPR_FIFO_SIZE(a)	(((a >> 16) & 0xff) * 16)
+
 
 struct dw8250_data {
 	int	last_lcr;
@@ -66,9 +95,6 @@ static unsigned int dw8250_serial_in32(struct uart_port *p, int offset)
 	return readl(p->membase + offset);
 }
 
-/* Offset for the DesignWare's UART Status Register. */
-#define UART_USR	0x1f
-
 static int dw8250_handle_irq(struct uart_port *p)
 {
 	struct dw8250_data *d = p->private_data;
@@ -78,7 +104,7 @@ static int dw8250_handle_irq(struct uart_port *p)
 		return 1;
 	} else if ((iir & UART_IIR_BUSY) == UART_IIR_BUSY) {
 		/* Clear the USR and write the LCR again. */
-		(void)p->serial_in(p, UART_USR);
+		(void)p->serial_in(p, DW_UART_USR);
 		p->serial_out(p, UART_LCR, d->last_lcr);
 
 		return 1;
@@ -87,61 +113,210 @@ static int dw8250_handle_irq(struct uart_port *p)
 	return 0;
 }
 
+static int dw8250_probe_of(struct uart_port *p)
+{
+	struct device_node	*np = p->dev->of_node;
+	u32			val;
+
+	if (!of_property_read_u32(np, "reg-io-width", &val)) {
+		switch (val) {
+		case 1:
+			break;
+		case 4:
+			p->iotype = UPIO_MEM32;
+			p->serial_in = dw8250_serial_in32;
+			p->serial_out = dw8250_serial_out32;
+			break;
+		default:
+			dev_err(p->dev, "unsupported reg-io-width (%u)\n", val);
+			return -EINVAL;
+		}
+	}
+
+	if (!of_property_read_u32(np, "reg-shift", &val))
+		p->regshift = val;
+
+	if (of_property_read_u32(np, "clock-frequency", &val)) {
+		dev_err(p->dev, "no clock-frequency property set\n");
+		return -EINVAL;
+	}
+	p->uartclk = val;
+
+	return 0;
+}
+
+#ifdef CONFIG_ACPI
+static bool dw8250_acpi_dma_filter(struct dma_chan *chan, void *parm)
+{
+	return chan->chan_id == *(int *)parm;
+}
+
+static acpi_status
+dw8250_acpi_walk_resource(struct acpi_resource *res, void *data)
+{
+	struct uart_port		*p = data;
+	struct uart_8250_port		*port;
+	struct uart_8250_dma		*dma;
+	struct acpi_resource_fixed_dma	*fixed_dma;
+	struct dma_slave_config		*slave;
+
+	port = container_of(p, struct uart_8250_port, port);
+
+	switch (res->type) {
+	case ACPI_RESOURCE_TYPE_FIXED_DMA:
+		fixed_dma = &res->data.fixed_dma;
+
+		/* TX comes first */
+		if (!port->dma) {
+			dma = devm_kzalloc(p->dev, sizeof(*dma), GFP_KERNEL);
+			if (!dma)
+				return AE_NO_MEMORY;
+
+			port->dma = dma;
+			slave = &dma->txconf;
+
+			slave->direction	= DMA_MEM_TO_DEV;
+			slave->dst_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;
+			slave->slave_id		= fixed_dma->request_lines;
+			slave->dst_maxburst	= port->tx_loadsz / 4;
+
+			dma->tx_chan_id		= fixed_dma->channels;
+			dma->tx_param		= &dma->tx_chan_id;
+			dma->fn			= dw8250_acpi_dma_filter;
+		} else {
+			dma = port->dma;
+			slave = &dma->rxconf;
+
+			slave->direction	= DMA_DEV_TO_MEM;
+			slave->src_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;
+			slave->slave_id		= fixed_dma->request_lines;
+			slave->src_maxburst	= p->fifosize / 4;
+
+			dma->rx_chan_id		= fixed_dma->channels;
+			dma->rx_param		= &dma->rx_chan_id;
+		}
+
+		break;
+	}
+
+	return AE_OK;
+}
+
+static int dw8250_probe_acpi(struct uart_port *p)
+{
+	const struct acpi_device_id *id;
+	acpi_status status;
+	u32 reg;
+
+	id = acpi_match_device(p->dev->driver->acpi_match_table, p->dev);
+	if (!id)
+		return -ENODEV;
+
+	p->iotype = UPIO_MEM32;
+	p->serial_in = dw8250_serial_in32;
+	p->serial_out = dw8250_serial_out32;
+	p->regshift = 2;
+	p->uartclk = (unsigned int)id->driver_data;
+
+	status = acpi_walk_resources(ACPI_HANDLE(p->dev), METHOD_NAME__CRS,
+				     dw8250_acpi_walk_resource, p);
+	if (ACPI_FAILURE(status)) {
+		dev_err_ratelimited(p->dev, "%s failed \"%s\"\n", __func__,
+				    acpi_format_exception(status));
+		return -ENODEV;
+	}
+
+	/* Fix Haswell issue where the clocks do not get enabled */
+	if (!strcmp(id->id, "INT33C4") || !strcmp(id->id, "INT33C5")) {
+		reg = readl(p->membase + LPSS_PRV_CLOCK_PARAMS);
+		writel(reg | 1, p->membase + LPSS_PRV_CLOCK_PARAMS);
+	}
+
+	return 0;
+}
+#else
+static inline int dw8250_probe_acpi(struct uart_port *p)
+{
+	return -ENODEV;
+}
+#endif /* CONFIG_ACPI */
+
+static void dw8250_setup_port(struct uart_8250_port *up)
+{
+	struct uart_port	*p = &up->port;
+	u32			reg = readl(p->membase + DW_UART_UCV);
+
+	/*
+	 * If the Component Version Register returns zero, we know that
+	 * ADDITIONAL_FEATURES are not enabled. No need to go any further.
+	 */
+	if (!reg)
+		return;
+
+	dev_dbg_ratelimited(p->dev, "Designware UART version %c.%c%c\n",
+		(reg >> 24) & 0xff, (reg >> 16) & 0xff, (reg >> 8) & 0xff);
+
+	reg = readl(p->membase + DW_UART_CPR);
+	if (!reg)
+		return;
+
+	/* Select the type based on fifo */
+	if (reg & DW_UART_CPR_FIFO_MODE) {
+		p->type = PORT_16550A;
+		p->flags |= UPF_FIXED_TYPE;
+		p->fifosize = DW_UART_CPR_FIFO_SIZE(reg);
+		up->tx_loadsz = p->fifosize;
+	}
+}
+
 static int dw8250_probe(struct platform_device *pdev)
 {
 	struct uart_8250_port uart = {};
 	struct resource *regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	struct resource *irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-	struct device_node *np = pdev->dev.of_node;
-	u32 val;
 	struct dw8250_data *data;
+	int err;
 
 	if (!regs || !irq) {
 		dev_err(&pdev->dev, "no registers/irq defined\n");
 		return -EINVAL;
 	}
 
-	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
-	if (!data)
-		return -ENOMEM;
-	uart.port.private_data = data;
-
 	spin_lock_init(&uart.port.lock);
 	uart.port.mapbase = regs->start;
 	uart.port.irq = irq->start;
 	uart.port.handle_irq = dw8250_handle_irq;
 	uart.port.type = PORT_8250;
-	uart.port.flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_IOREMAP |
-		UPF_FIXED_PORT | UPF_FIXED_TYPE;
+	uart.port.flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_FIXED_PORT;
 	uart.port.dev = &pdev->dev;
 
+	uart.port.membase = ioremap(regs->start, resource_size(regs));
+	if (!uart.port.membase)
+		return -ENOMEM;
+
 	uart.port.iotype = UPIO_MEM;
 	uart.port.serial_in = dw8250_serial_in;
 	uart.port.serial_out = dw8250_serial_out;
-	if (!of_property_read_u32(np, "reg-io-width", &val)) {
-		switch (val) {
-		case 1:
-			break;
-		case 4:
-			uart.port.iotype = UPIO_MEM32;
-			uart.port.serial_in = dw8250_serial_in32;
-			uart.port.serial_out = dw8250_serial_out32;
-			break;
-		default:
-			dev_err(&pdev->dev, "unsupported reg-io-width (%u)\n",
-				val);
-			return -EINVAL;
-		}
+
+	dw8250_setup_port(&uart);
+
+	if (pdev->dev.of_node) {
+		err = dw8250_probe_of(&uart.port);
+		if (err)
+			return err;
+	} else if (ACPI_HANDLE(&pdev->dev)) {
+		err = dw8250_probe_acpi(&uart.port);
+		if (err)
+			return err;
+	} else {
+		return -ENODEV;
 	}
 
-	if (!of_property_read_u32(np, "reg-shift", &val))
-		uart.port.regshift = val;
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
 
-	if (of_property_read_u32(np, "clock-frequency", &val)) {
-		dev_err(&pdev->dev, "no clock-frequency property set\n");
-		return -EINVAL;
-	}
-	uart.port.uartclk = val;
+	uart.port.private_data = data;
 
 	data->line = serial8250_register_8250_port(&uart);
 	if (data->line < 0)
@@ -184,17 +359,25 @@ static int dw8250_resume(struct platform_device *pdev)
 #define dw8250_resume NULL
 #endif /* CONFIG_PM */
 
-static const struct of_device_id dw8250_match[] = {
+static const struct of_device_id dw8250_of_match[] = {
 	{ .compatible = "snps,dw-apb-uart" },
 	{ /* Sentinel */ }
 };
-MODULE_DEVICE_TABLE(of, dw8250_match);
+MODULE_DEVICE_TABLE(of, dw8250_of_match);
+
+static const struct acpi_device_id dw8250_acpi_match[] = {
+	{ "INT33C4", 100000000 },
+	{ "INT33C5", 100000000 },
+	{ },
+};
+MODULE_DEVICE_TABLE(acpi, dw8250_acpi_match);
 
 static struct platform_driver dw8250_platform_driver = {
 	.driver = {
 		.name		= "dw-apb-uart",
 		.owner		= THIS_MODULE,
-		.of_match_table	= dw8250_match,
+		.of_match_table	= dw8250_of_match,
+		.acpi_match_table = ACPI_PTR(dw8250_acpi_match),
 	},
 	.probe			= dw8250_probe,
 	.remove			= dw8250_remove,
diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
index f53a7db4350..721904f8efa 100644
--- a/drivers/tty/serial/8250/8250_early.c
+++ b/drivers/tty/serial/8250/8250_early.c
@@ -194,7 +194,7 @@ static int __init parse_options(struct early_serial8250_device *device,
 		options++;
 		device->baud = simple_strtoul(options, NULL, 0);
 		length = min(strcspn(options, " "), sizeof(device->options));
-		strncpy(device->options, options, length);
+		strlcpy(device->options, options, length);
 	} else {
 		device->baud = probe_baud(port);
 		snprintf(device->options, sizeof(device->options), "%u",
diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c
index a27a98e1b06..791c5a77ec6 100644
--- a/drivers/tty/serial/8250/8250_pci.c
+++ b/drivers/tty/serial/8250/8250_pci.c
@@ -1040,6 +1040,253 @@ static int pci_asix_setup(struct serial_private *priv,
 	return pci_default_setup(priv, board, port, idx);
 }
 
+/* Quatech devices have their own extra interface features */
+
+struct quatech_feature {
+	u16 devid;
+	bool amcc;
+};
+
+#define QPCR_TEST_FOR1		0x3F
+#define QPCR_TEST_GET1		0x00
+#define QPCR_TEST_FOR2		0x40
+#define QPCR_TEST_GET2		0x40
+#define QPCR_TEST_FOR3		0x80
+#define QPCR_TEST_GET3		0x40
+#define QPCR_TEST_FOR4		0xC0
+#define QPCR_TEST_GET4		0x80
+
+#define QOPR_CLOCK_X1		0x0000
+#define QOPR_CLOCK_X2		0x0001
+#define QOPR_CLOCK_X4		0x0002
+#define QOPR_CLOCK_X8		0x0003
+#define QOPR_CLOCK_RATE_MASK	0x0003
+
+
+static struct quatech_feature quatech_cards[] = {
+	{ PCI_DEVICE_ID_QUATECH_QSC100,   1 },
+	{ PCI_DEVICE_ID_QUATECH_DSC100,   1 },
+	{ PCI_DEVICE_ID_QUATECH_DSC100E,  0 },
+	{ PCI_DEVICE_ID_QUATECH_DSC200,   1 },
+	{ PCI_DEVICE_ID_QUATECH_DSC200E,  0 },
+	{ PCI_DEVICE_ID_QUATECH_ESC100D,  1 },
+	{ PCI_DEVICE_ID_QUATECH_ESC100M,  1 },
+	{ PCI_DEVICE_ID_QUATECH_QSCP100,  1 },
+	{ PCI_DEVICE_ID_QUATECH_DSCP100,  1 },
+	{ PCI_DEVICE_ID_QUATECH_QSCP200,  1 },
+	{ PCI_DEVICE_ID_QUATECH_DSCP200,  1 },
+	{ PCI_DEVICE_ID_QUATECH_ESCLP100, 0 },
+	{ PCI_DEVICE_ID_QUATECH_QSCLP100, 0 },
+	{ PCI_DEVICE_ID_QUATECH_DSCLP100, 0 },
+	{ PCI_DEVICE_ID_QUATECH_SSCLP100, 0 },
+	{ PCI_DEVICE_ID_QUATECH_QSCLP200, 0 },
+	{ PCI_DEVICE_ID_QUATECH_DSCLP200, 0 },
+	{ PCI_DEVICE_ID_QUATECH_SSCLP200, 0 },
+	{ PCI_DEVICE_ID_QUATECH_SPPXP_100, 0 },
+	{ 0, }
+};
+
+static int pci_quatech_amcc(u16 devid)
+{
+	struct quatech_feature *qf = &quatech_cards[0];
+	while (qf->devid) {
+		if (qf->devid == devid)
+			return qf->amcc;
+		qf++;
+	}
+	pr_err("quatech: unknown port type '0x%04X'.\n", devid);
+	return 0;
+};
+
+static int pci_quatech_rqopr(struct uart_8250_port *port)
+{
+	unsigned long base = port->port.iobase;
+	u8 LCR, val;
+
+	LCR = inb(base + UART_LCR);
+	outb(0xBF, base + UART_LCR);
+	val = inb(base + UART_SCR);
+	outb(LCR, base + UART_LCR);
+	return val;
+}
+
+static void pci_quatech_wqopr(struct uart_8250_port *port, u8 qopr)
+{
+	unsigned long base = port->port.iobase;
+	u8 LCR, val;
+
+	LCR = inb(base + UART_LCR);
+	outb(0xBF, base + UART_LCR);
+	val = inb(base + UART_SCR);
+	outb(qopr, base + UART_SCR);
+	outb(LCR, base + UART_LCR);
+}
+
+static int pci_quatech_rqmcr(struct uart_8250_port *port)
+{
+	unsigned long base = port->port.iobase;
+	u8 LCR, val, qmcr;
+
+	LCR = inb(base + UART_LCR);
+	outb(0xBF, base + UART_LCR);
+	val = inb(base + UART_SCR);
+	outb(val | 0x10, base + UART_SCR);
+	qmcr = inb(base + UART_MCR);
+	outb(val, base + UART_SCR);
+	outb(LCR, base + UART_LCR);
+
+	return qmcr;
+}
+
+static void pci_quatech_wqmcr(struct uart_8250_port *port, u8 qmcr)
+{
+	unsigned long base = port->port.iobase;
+	u8 LCR, val;
+
+	LCR = inb(base + UART_LCR);
+	outb(0xBF, base + UART_LCR);
+	val = inb(base + UART_SCR);
+	outb(val | 0x10, base + UART_SCR);
+	outb(qmcr, base + UART_MCR);
+	outb(val, base + UART_SCR);
+	outb(LCR, base + UART_LCR);
+}
+
+static int pci_quatech_has_qmcr(struct uart_8250_port *port)
+{
+	unsigned long base = port->port.iobase;
+	u8 LCR, val;
+
+	LCR = inb(base + UART_LCR);
+	outb(0xBF, base + UART_LCR);
+	val = inb(base + UART_SCR);
+	if (val & 0x20) {
+		outb(0x80, UART_LCR);
+		if (!(inb(UART_SCR) & 0x20)) {
+			outb(LCR, base + UART_LCR);
+			return 1;
+		}
+	}
+	return 0;
+}
+
+static int pci_quatech_test(struct uart_8250_port *port)
+{
+	u8 reg;
+	u8 qopr = pci_quatech_rqopr(port);
+	pci_quatech_wqopr(port, qopr & QPCR_TEST_FOR1);
+	reg = pci_quatech_rqopr(port) & 0xC0;
+	if (reg != QPCR_TEST_GET1)
+		return -EINVAL;
+	pci_quatech_wqopr(port, (qopr & QPCR_TEST_FOR1)|QPCR_TEST_FOR2);
+	reg = pci_quatech_rqopr(port) & 0xC0;
+	if (reg != QPCR_TEST_GET2)
+		return -EINVAL;
+	pci_quatech_wqopr(port, (qopr & QPCR_TEST_FOR1)|QPCR_TEST_FOR3);
+	reg = pci_quatech_rqopr(port) & 0xC0;
+	if (reg != QPCR_TEST_GET3)
+		return -EINVAL;
+	pci_quatech_wqopr(port, (qopr & QPCR_TEST_FOR1)|QPCR_TEST_FOR4);
+	reg = pci_quatech_rqopr(port) & 0xC0;
+	if (reg != QPCR_TEST_GET4)
+		return -EINVAL;
+
+	pci_quatech_wqopr(port, qopr);
+	return 0;
+}
+
+static int pci_quatech_clock(struct uart_8250_port *port)
+{
+	u8 qopr, reg, set;
+	unsigned long clock;
+
+	if (pci_quatech_test(port) < 0)
+		return 1843200;
+
+	qopr = pci_quatech_rqopr(port);
+
+	pci_quatech_wqopr(port, qopr & ~QOPR_CLOCK_X8);
+	reg = pci_quatech_rqopr(port);
+	if (reg & QOPR_CLOCK_X8) {
+		clock = 1843200;
+		goto out;
+	}
+	pci_quatech_wqopr(port, qopr | QOPR_CLOCK_X8);
+	reg = pci_quatech_rqopr(port);
+	if (!(reg & QOPR_CLOCK_X8)) {
+		clock = 1843200;
+		goto out;
+	}
+	reg &= QOPR_CLOCK_X8;
+	if (reg == QOPR_CLOCK_X2) {
+		clock =  3685400;
+		set = QOPR_CLOCK_X2;
+	} else if (reg == QOPR_CLOCK_X4) {
+		clock = 7372800;
+		set = QOPR_CLOCK_X4;
+	} else if (reg == QOPR_CLOCK_X8) {
+		clock = 14745600;
+		set = QOPR_CLOCK_X8;
+	} else {
+		clock = 1843200;
+		set = QOPR_CLOCK_X1;
+	}
+	qopr &= ~QOPR_CLOCK_RATE_MASK;
+	qopr |= set;
+
+out:
+	pci_quatech_wqopr(port, qopr);
+	return clock;
+}
+
+static int pci_quatech_rs422(struct uart_8250_port *port)
+{
+	u8 qmcr;
+	int rs422 = 0;
+
+	if (!pci_quatech_has_qmcr(port))
+		return 0;
+	qmcr = pci_quatech_rqmcr(port);
+	pci_quatech_wqmcr(port, 0xFF);
+	if (pci_quatech_rqmcr(port))
+		rs422 = 1;
+	pci_quatech_wqmcr(port, qmcr);
+	return rs422;
+}
+
+static int pci_quatech_init(struct pci_dev *dev)
+{
+	if (pci_quatech_amcc(dev->device)) {
+		unsigned long base = pci_resource_start(dev, 0);
+		if (base) {
+			u32 tmp;
+			outl(inl(base + 0x38), base + 0x38);
+			tmp = inl(base + 0x3c);
+			outl(tmp | 0x01000000, base + 0x3c);
+			outl(tmp, base + 0x3c);
+		}
+	}
+	return 0;
+}
+
+static int pci_quatech_setup(struct serial_private *priv,
+		  const struct pciserial_board *board,
+		  struct uart_8250_port *port, int idx)
+{
+	/* Needed by pci_quatech calls below */
+	port->port.iobase = pci_resource_start(priv->dev, FL_GET_BASE(board->flags));
+	/* Set up the clocking */
+	port->port.uartclk = pci_quatech_clock(port);
+	/* For now just warn about RS422 */
+	if (pci_quatech_rs422(port))
+		pr_warn("quatech: software control of RS422 features not currently supported.\n");
+	return pci_default_setup(priv, board, port, idx);
+}
+
+static void pci_quatech_exit(struct pci_dev *dev)
+{
+}
+
 static int pci_default_setup(struct serial_private *priv,
 		  const struct pciserial_board *board,
 		  struct uart_8250_port *port, int idx)
@@ -1318,6 +1565,9 @@ pci_wch_ch353_setup(struct serial_private *priv,
 #define PCI_DEVICE_ID_COMMTECH_4222PCIE	0x0022
 #define PCI_DEVICE_ID_BROADCOM_TRUMANAGE 0x160a
 
+#define PCI_VENDOR_ID_SUNIX		0x1fd4
+#define PCI_DEVICE_ID_SUNIX_1999	0x1999
+
 
 /* Unknown vendors/cards - this should not be in linux/pci_ids.h */
 #define PCI_SUBDEVICE_ID_UNKNOWN_0x1584	0x1584
@@ -1541,6 +1791,16 @@ static struct pci_serial_quirk pci_serial_quirks[] __refdata = {
 		.setup		= pci_ni8430_setup,
 		.exit		= pci_ni8430_exit,
 	},
+	/* Quatech */
+	{
+		.vendor		= PCI_VENDOR_ID_QUATECH,
+		.device		= PCI_ANY_ID,
+		.subvendor	= PCI_ANY_ID,
+		.subdevice	= PCI_ANY_ID,
+		.init		= pci_quatech_init,
+		.setup		= pci_quatech_setup,
+		.exit		= pci_quatech_exit,
+	},
 	/*
 	 * Panacom
 	 */
@@ -1704,6 +1964,23 @@ static struct pci_serial_quirk pci_serial_quirks[] __refdata = {
 		.setup		= pci_timedia_setup,
 	},
 	/*
+	 * SUNIX (Timedia) cards
+	 * Do not "probe" for these cards as there is at least one combination
+	 * card that should be handled by parport_pc that doesn't match the
+	 * rule in pci_timedia_probe.
+	 * It is part number is MIO5079A but its subdevice ID is 0x0102.
+	 * There are some boards with part number SER5037AL that report
+	 * subdevice ID 0x0002.
+	 */
+	{
+		.vendor		= PCI_VENDOR_ID_SUNIX,
+		.device		= PCI_DEVICE_ID_SUNIX_1999,
+		.subvendor	= PCI_VENDOR_ID_SUNIX,
+		.subdevice	= PCI_ANY_ID,
+		.init		= pci_timedia_init,
+		.setup		= pci_timedia_setup,
+	},
+	/*
 	 * Exar cards
 	 */
 	{
@@ -3506,18 +3783,70 @@ static struct pci_device_id serial_pci_tbl[] = {
 	{	PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_ROMULUS,
 		0x10b5, 0x106a, 0, 0,
 		pbn_plx_romulus },
+	/*
+	 * Quatech cards. These actually have configurable clocks but for
+	 * now we just use the default.
+	 *
+	 * 100 series are RS232, 200 series RS422,
+	 */
 	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_QSC100,
 		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
 		pbn_b1_4_115200 },
 	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_DSC100,
 		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
 		pbn_b1_2_115200 },
+	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_DSC100E,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b2_2_115200 },
+	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_DSC200,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b1_2_115200 },
+	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_DSC200E,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b2_2_115200 },
+	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_QSC200,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b1_4_115200 },
 	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_ESC100D,
 		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
 		pbn_b1_8_115200 },
 	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_ESC100M,
 		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
 		pbn_b1_8_115200 },
+	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_QSCP100,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b1_4_115200 },
+	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_DSCP100,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b1_2_115200 },
+	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_QSCP200,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b1_4_115200 },
+	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_DSCP200,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b1_2_115200 },
+	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_QSCLP100,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b2_4_115200 },
+	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_DSCLP100,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b2_2_115200 },
+	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_SSCLP100,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b2_1_115200 },
+	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_QSCLP200,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b2_4_115200 },
+	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_DSCLP200,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b2_2_115200 },
+	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_SSCLP200,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b2_1_115200 },
+	{	PCI_VENDOR_ID_QUATECH, PCI_DEVICE_ID_QUATECH_ESCLP100,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b0_8_115200 },
+
 	{	PCI_VENDOR_ID_SPECIALIX, PCI_DEVICE_ID_OXSEMI_16PCI954,
 		PCI_VENDOR_ID_SPECIALIX, PCI_SUBDEVICE_ID_SPECIALIX_SPEED4,
 		0, 0,
@@ -3902,6 +4231,19 @@ static struct pci_device_id serial_pci_tbl[] = {
 		pbn_b0_bt_1_921600 },
 
 	/*
+	 * SUNIX (TIMEDIA)
+	 */
+	{	PCI_VENDOR_ID_SUNIX, PCI_DEVICE_ID_SUNIX_1999,
+		PCI_VENDOR_ID_SUNIX, PCI_ANY_ID,
+		PCI_CLASS_COMMUNICATION_SERIAL << 8, 0xffff00,
+		pbn_b0_bt_1_921600 },
+
+	{	PCI_VENDOR_ID_SUNIX, PCI_DEVICE_ID_SUNIX_1999,
+		PCI_VENDOR_ID_SUNIX, PCI_ANY_ID,
+		PCI_CLASS_COMMUNICATION_MULTISERIAL << 8, 0xffff00,
+		pbn_b0_bt_1_921600 },
+
+	/*
 	 * AFAVLAB serial card, from Harald Welte <laforge@gnumonks.org>
 	 */
 	{	PCI_VENDOR_ID_AFAVLAB, PCI_DEVICE_ID_AFAVLAB_P028,
diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig
index c31133a6ea8..2ef9537bcb2 100644
--- a/drivers/tty/serial/8250/Kconfig
+++ b/drivers/tty/serial/8250/Kconfig
@@ -84,6 +84,14 @@ config SERIAL_8250_GSC
 	depends on SERIAL_8250 && GSC
 	default SERIAL_8250
 
+config SERIAL_8250_DMA
+	bool "DMA support for 16550 compatible UART controllers" if EXPERT
+	depends on SERIAL_8250 && DMADEVICES=y
+	default SERIAL_8250
+	help
+	  This builds DMA support that can be used with 8250/16650
+	  compatible UART controllers that support DMA signaling.
+
 config SERIAL_8250_PCI
 	tristate "8250/16550 PCI device support" if EXPERT
 	depends on SERIAL_8250 && PCI
@@ -249,15 +257,6 @@ config SERIAL_8250_ACORN
 	  system, say Y to this option.  The driver can handle 1, 2, or 3 port
 	  cards.  If unsure, say N.
 
-config SERIAL_8250_RM9K
-	bool "Support for MIPS RM9xxx integrated serial port"
-	depends on SERIAL_8250 != n && SERIAL_RM9000
-	select SERIAL_8250_SHARE_IRQ
-	help
-	  Selecting this option will add support for the integrated serial
-	  port hardware found on MIPS RM9122 and similar processors.
-	  If unsure, say N.
-
 config SERIAL_8250_FSL
 	bool
 	depends on SERIAL_8250_CONSOLE && PPC_UDBG_16550
@@ -265,7 +264,7 @@ config SERIAL_8250_FSL
 
 config SERIAL_8250_DW
 	tristate "Support for Synopsys DesignWare 8250 quirks"
-	depends on SERIAL_8250 && OF
+	depends on SERIAL_8250
 	help
 	  Selecting this option will enable handling of the extra features
 	  present in the Synopsys DesignWare APB UART.
@@ -277,3 +276,11 @@ config SERIAL_8250_EM
 	  Selecting this option will add support for the integrated serial
 	  port hardware found on the Emma Mobile line of processors.
 	  If unsure, say N.
+
+config SERIAL_8250_RT288X
+	bool "Ralink RT288x/RT305x/RT3662/RT3883 serial port support"
+	depends on SERIAL_8250 && (SOC_RT288X || SOC_RT305X || SOC_RT3883)
+	help
+	  If you have a Ralink RT288x/RT305x SoC based board and want to use the
+	  serial port, say Y to this option. The driver can handle up to 2 serial
+	  ports. If unsure, say N.
diff --git a/drivers/tty/serial/8250/Makefile b/drivers/tty/serial/8250/Makefile
index 108fe7fe13e..a23838a4d53 100644
--- a/drivers/tty/serial/8250/Makefile
+++ b/drivers/tty/serial/8250/Makefile
@@ -5,6 +5,7 @@
 obj-$(CONFIG_SERIAL_8250)		+= 8250_core.o
 8250_core-y				:= 8250.o
 8250_core-$(CONFIG_SERIAL_8250_PNP)	+= 8250_pnp.o
+8250_core-$(CONFIG_SERIAL_8250_DMA)	+= 8250_dma.o
 obj-$(CONFIG_SERIAL_8250_GSC)		+= 8250_gsc.o
 obj-$(CONFIG_SERIAL_8250_PCI)		+= 8250_pci.o
 obj-$(CONFIG_SERIAL_8250_HP300)		+= 8250_hp300.o
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 59c23d03810..a0162cbf055 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -2,8 +2,10 @@
 # Serial device configuration
 #
 
+if TTY
+
 menu "Serial drivers"
-	depends on HAS_IOMEM
+	depends on HAS_IOMEM && GENERIC_HARDIRQS
 
 source "drivers/tty/serial/8250/Kconfig"
 
@@ -269,6 +271,17 @@ config SERIAL_SIRFSOC_CONSOLE
           your boot loader about how to pass options to the kernel at
           boot time.)
 
+config SERIAL_TEGRA
+	tristate "NVIDIA Tegra20/30 SoC serial controller"
+	depends on ARCH_TEGRA && TEGRA20_APB_DMA
+	select SERIAL_CORE
+	help
+	  Support for the on-chip UARTs on the NVIDIA Tegra series SOCs
+	  providing /dev/ttyHS0, 1, 2, 3 and 4 (note, some machines may not
+	  provide all of these ports, depending on how the serial port
+	  are enabled). This driver uses the APB DMA to achieve higher baudrate
+	  and better performance.
+
 config SERIAL_MAX3100
 	tristate "MAX3100 support"
 	depends on SPI
@@ -1447,4 +1460,30 @@ config SERIAL_ARC_NR_PORTS
 	  Set this to the number of serial ports you want the driver
 	  to support.
 
+config SERIAL_RP2
+	tristate "Comtrol RocketPort EXPRESS/INFINITY support"
+	depends on PCI
+	select SERIAL_CORE
+	help
+	  This driver supports the Comtrol RocketPort EXPRESS and
+	  RocketPort INFINITY families of PCI/PCIe multiport serial adapters.
+	  These adapters use a "RocketPort 2" ASIC that is not compatible
+	  with the original RocketPort driver (CONFIG_ROCKETPORT).
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called rp2.
+
+	  If you want to compile this driver into the kernel, say Y here.  If
+	  you don't have a suitable RocketPort card installed, say N.
+
+config SERIAL_RP2_NR_UARTS
+	int "Maximum number of RocketPort EXPRESS/INFINITY ports"
+	depends on SERIAL_RP2
+	default "32"
+	help
+	  If multiple cards are present, the default limit of 32 ports may
+	  need to be increased.
+
 endmenu
+
+endif # TTY
diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
index df1b998c436..eedfec40e3d 100644
--- a/drivers/tty/serial/Makefile
+++ b/drivers/tty/serial/Makefile
@@ -80,6 +80,8 @@ obj-$(CONFIG_SERIAL_MXS_AUART) += mxs-auart.o
 obj-$(CONFIG_SERIAL_LANTIQ)	+= lantiq.o
 obj-$(CONFIG_SERIAL_XILINX_PS_UART) += xilinx_uartps.o
 obj-$(CONFIG_SERIAL_SIRFSOC) += sirfsoc_uart.o
+obj-$(CONFIG_SERIAL_TEGRA) += serial-tegra.o
 obj-$(CONFIG_SERIAL_AR933X)   += ar933x_uart.o
 obj-$(CONFIG_SERIAL_EFM32_UART) += efm32-uart.o
 obj-$(CONFIG_SERIAL_ARC)	+= arc_uart.o
+obj-$(CONFIG_SERIAL_RP2)	+= rp2.o
diff --git a/drivers/tty/serial/altera_jtaguart.c b/drivers/tty/serial/altera_jtaguart.c
index 872f14ae43d..c6bdb943726 100644
--- a/drivers/tty/serial/altera_jtaguart.c
+++ b/drivers/tty/serial/altera_jtaguart.c
@@ -139,7 +139,7 @@ static void altera_jtaguart_rx_chars(struct altera_jtaguart *pp)
 		uart_insert_char(port, 0, 0, ch, flag);
 	}
 
-	tty_flip_buffer_push(port->state->port.tty);
+	tty_flip_buffer_push(&port->state->port);
 }
 
 static void altera_jtaguart_tx_chars(struct altera_jtaguart *pp)
@@ -493,11 +493,9 @@ static int __init altera_jtaguart_init(void)
 	if (rc)
 		return rc;
 	rc = platform_driver_register(&altera_jtaguart_platform_driver);
-	if (rc) {
+	if (rc)
 		uart_unregister_driver(&altera_jtaguart_driver);
-		return rc;
-	}
-	return 0;
+	return rc;
 }
 
 static void __exit altera_jtaguart_exit(void)
diff --git a/drivers/tty/serial/altera_uart.c b/drivers/tty/serial/altera_uart.c
index 684a0808e1c..13471dd9579 100644
--- a/drivers/tty/serial/altera_uart.c
+++ b/drivers/tty/serial/altera_uart.c
@@ -231,7 +231,7 @@ static void altera_uart_rx_chars(struct altera_uart *pp)
 				 flag);
 	}
 
-	tty_flip_buffer_push(port->state->port.tty);
+	tty_flip_buffer_push(&port->state->port);
 }
 
 static void altera_uart_tx_chars(struct altera_uart *pp)
@@ -637,11 +637,9 @@ static int __init altera_uart_init(void)
 	if (rc)
 		return rc;
 	rc = platform_driver_register(&altera_uart_platform_driver);
-	if (rc) {
+	if (rc)
 		uart_unregister_driver(&altera_uart_driver);
-		return rc;
-	}
-	return 0;
+	return rc;
 }
 
 static void __exit altera_uart_exit(void)
diff --git a/drivers/tty/serial/amba-pl010.c b/drivers/tty/serial/amba-pl010.c
index 22317dd1647..c3684051952 100644
--- a/drivers/tty/serial/amba-pl010.c
+++ b/drivers/tty/serial/amba-pl010.c
@@ -116,7 +116,6 @@ static void pl010_enable_ms(struct uart_port *port)
 
 static void pl010_rx_chars(struct uart_amba_port *uap)
 {
-	struct tty_struct *tty = uap->port.state->port.tty;
 	unsigned int status, ch, flag, rsr, max_count = 256;
 
 	status = readb(uap->port.membase + UART01x_FR);
@@ -165,7 +164,7 @@ static void pl010_rx_chars(struct uart_amba_port *uap)
 		status = readb(uap->port.membase + UART01x_FR);
 	}
 	spin_unlock(&uap->port.lock);
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&uap->port.state->port);
 	spin_lock(&uap->port.lock);
 }
 
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 7fca4022a8b..3ea5408fcbe 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -698,7 +698,7 @@ static void pl011_dma_rx_chars(struct uart_amba_port *uap,
 			       u32 pending, bool use_buf_b,
 			       bool readfifo)
 {
-	struct tty_struct *tty = uap->port.state->port.tty;
+	struct tty_port *port = &uap->port.state->port;
 	struct pl011_sgbuf *sgbuf = use_buf_b ?
 		&uap->dmarx.sgbuf_b : &uap->dmarx.sgbuf_a;
 	struct device *dev = uap->dmarx.chan->device->dev;
@@ -715,8 +715,7 @@ static void pl011_dma_rx_chars(struct uart_amba_port *uap,
 		 * Note that tty_insert_flip_buf() tries to take as many chars
 		 * as it can.
 		 */
-		dma_count = tty_insert_flip_string(uap->port.state->port.tty,
-						   sgbuf->buf, pending);
+		dma_count = tty_insert_flip_string(port, sgbuf->buf, pending);
 
 		/* Return buffer to device */
 		dma_sync_sg_for_device(dev, &sgbuf->sg, 1, DMA_FROM_DEVICE);
@@ -754,7 +753,7 @@ static void pl011_dma_rx_chars(struct uart_amba_port *uap,
 	dev_vdbg(uap->port.dev,
 		 "Took %d chars from DMA buffer and %d chars from the FIFO\n",
 		 dma_count, fifotaken);
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(port);
 	spin_lock(&uap->port.lock);
 }
 
@@ -1076,12 +1075,10 @@ static void pl011_enable_ms(struct uart_port *port)
 
 static void pl011_rx_chars(struct uart_amba_port *uap)
 {
-	struct tty_struct *tty = uap->port.state->port.tty;
-
 	pl011_fifo_to_tty(uap);
 
 	spin_unlock(&uap->port.lock);
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&uap->port.state->port);
 	/*
 	 * If we were temporarily out of DMA mode for a while,
 	 * attempt to switch back to DMA mode again.
diff --git a/drivers/tty/serial/apbuart.c b/drivers/tty/serial/apbuart.c
index 59ae2b53e76..6331464d910 100644
--- a/drivers/tty/serial/apbuart.c
+++ b/drivers/tty/serial/apbuart.c
@@ -78,7 +78,6 @@ static void apbuart_enable_ms(struct uart_port *port)
 
 static void apbuart_rx_chars(struct uart_port *port)
 {
-	struct tty_struct *tty = port->state->port.tty;
 	unsigned int status, ch, rsr, flag;
 	unsigned int max_chars = port->fifosize;
 
@@ -126,7 +125,7 @@ static void apbuart_rx_chars(struct uart_port *port)
 		status = UART_GET_STATUS(port);
 	}
 
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&port->state->port);
 }
 
 static void apbuart_tx_chars(struct uart_port *port)
diff --git a/drivers/tty/serial/ar933x_uart.c b/drivers/tty/serial/ar933x_uart.c
index 505c490c0b4..27f20c57abe 100644
--- a/drivers/tty/serial/ar933x_uart.c
+++ b/drivers/tty/serial/ar933x_uart.c
@@ -297,10 +297,9 @@ static void ar933x_uart_set_termios(struct uart_port *port,
 
 static void ar933x_uart_rx_chars(struct ar933x_uart_port *up)
 {
-	struct tty_struct *tty;
+	struct tty_port *port = &up->port.state->port;
 	int max_count = 256;
 
-	tty = tty_port_tty_get(&up->port.state->port);
 	do {
 		unsigned int rdata;
 		unsigned char ch;
@@ -313,11 +312,6 @@ static void ar933x_uart_rx_chars(struct ar933x_uart_port *up)
 		ar933x_uart_write(up, AR933X_UART_DATA_REG,
 				  AR933X_UART_DATA_RX_CSR);
 
-		if (!tty) {
-			/* discard the data if no tty available */
-			continue;
-		}
-
 		up->port.icount.rx++;
 		ch = rdata & AR933X_UART_DATA_TX_RX_MASK;
 
@@ -325,13 +319,10 @@ static void ar933x_uart_rx_chars(struct ar933x_uart_port *up)
 			continue;
 
 		if ((up->port.ignore_status_mask & AR933X_DUMMY_STATUS_RD) == 0)
-			tty_insert_flip_char(tty, ch, TTY_NORMAL);
+			tty_insert_flip_char(port, ch, TTY_NORMAL);
 	} while (max_count-- > 0);
 
-	if (tty) {
-		tty_flip_buffer_push(tty);
-		tty_kref_put(tty);
-	}
+	tty_flip_buffer_push(port);
 }
 
 static void ar933x_uart_tx_chars(struct ar933x_uart_port *up)
diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c
index 3e0b3fac6a0..d97e194b6bc 100644
--- a/drivers/tty/serial/arc_uart.c
+++ b/drivers/tty/serial/arc_uart.c
@@ -37,6 +37,8 @@
 #include <linux/tty_flip.h>
 #include <linux/serial_core.h>
 #include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
 
 /*************************************
  * ARC UART Hardware Specs
@@ -209,12 +211,8 @@ static void arc_serial_start_tx(struct uart_port *port)
 
 static void arc_serial_rx_chars(struct arc_uart_port *uart)
 {
-	struct tty_struct *tty = tty_port_tty_get(&uart->port.state->port);
 	unsigned int status, ch, flg = 0;
 
-	if (!tty)
-		return;
-
 	/*
 	 * UART has 4 deep RX-FIFO. Driver's recongnition of this fact
 	 * is very subtle. Here's how ...
@@ -250,10 +248,8 @@ static void arc_serial_rx_chars(struct arc_uart_port *uart)
 		uart_insert_char(&uart->port, status, RXOERR, ch, flg);
 
 done:
-		tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(&uart->port.state->port);
 	}
-
-	tty_kref_put(tty);
 }
 
 /*
@@ -526,18 +522,37 @@ static struct uart_ops arc_serial_pops = {
 };
 
 static int
-arc_uart_init_one(struct platform_device *pdev, struct arc_uart_port *uart)
+arc_uart_init_one(struct platform_device *pdev, int dev_id)
 {
 	struct resource *res, *res2;
 	unsigned long *plat_data;
-
-	if (pdev->id < 0 || pdev->id >= CONFIG_SERIAL_ARC_NR_PORTS) {
-		dev_err(&pdev->dev, "Wrong uart platform device id.\n");
-		return -ENOENT;
-	}
+	struct arc_uart_port *uart = &arc_uart_ports[dev_id];
 
 	plat_data = ((unsigned long *)(pdev->dev.platform_data));
-	uart->baud = plat_data[0];
+	if (!plat_data)
+		return -ENODEV;
+
+	uart->is_emulated = !!plat_data[0];	/* workaround ISS bug */
+
+	if (is_early_platform_device(pdev)) {
+		uart->port.uartclk = plat_data[1];
+		uart->baud = plat_data[2];
+	} else {
+		struct device_node *np = pdev->dev.of_node;
+		u32 val;
+
+		if (of_property_read_u32(np, "clock-frequency", &val)) {
+			dev_err(&pdev->dev, "clock-frequency property NOTset\n");
+			return -EINVAL;
+		}
+		uart->port.uartclk = val;
+
+		if (of_property_read_u32(np, "current-speed", &val)) {
+			dev_err(&pdev->dev, "current-speed property NOT set\n");
+			return -EINVAL;
+		}
+		uart->baud = val;
+	}
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res)
@@ -557,10 +572,9 @@ arc_uart_init_one(struct platform_device *pdev, struct arc_uart_port *uart)
 	uart->port.dev = &pdev->dev;
 	uart->port.iotype = UPIO_MEM;
 	uart->port.flags = UPF_BOOT_AUTOCONF;
-	uart->port.line = pdev->id;
+	uart->port.line = dev_id;
 	uart->port.ops = &arc_serial_pops;
 
-	uart->port.uartclk = plat_data[1];
 	uart->port.fifosize = ARC_UART_TX_FIFO_SIZE;
 
 	/*
@@ -569,9 +583,6 @@ arc_uart_init_one(struct platform_device *pdev, struct arc_uart_port *uart)
 	 */
 	uart->port.ignore_status_mask = 0;
 
-	/* Real Hardware vs. emulated to work around a bug */
-	uart->is_emulated = !!plat_data[2];
-
 	return 0;
 }
 
@@ -648,45 +659,50 @@ static __init void early_serial_write(struct console *con, const char *s,
 	}
 }
 
-static struct __initdata console arc_early_serial_console = {
+static struct console arc_early_serial_console __initdata = {
 	.name = "early_ARCuart",
 	.write = early_serial_write,
 	.flags = CON_PRINTBUFFER | CON_BOOT,
 	.index = -1
 };
 
-static int arc_serial_probe_earlyprintk(struct platform_device *pdev)
+static int __init arc_serial_probe_earlyprintk(struct platform_device *pdev)
 {
-	arc_early_serial_console.index = pdev->id;
+	int dev_id = pdev->id < 0 ? 0 : pdev->id;
+	int rc;
+
+	arc_early_serial_console.index = dev_id;
 
-	arc_uart_init_one(pdev, &arc_uart_ports[pdev->id]);
+	rc = arc_uart_init_one(pdev, dev_id);
+	if (rc)
+		panic("early console init failed\n");
 
 	arc_serial_console_setup(&arc_early_serial_console, NULL);
 
 	register_console(&arc_early_serial_console);
 	return 0;
 }
-#else
-static int arc_serial_probe_earlyprintk(struct platform_device *pdev)
-{
-	return -ENODEV;
-}
 #endif	/* CONFIG_SERIAL_ARC_CONSOLE */
 
 static int arc_serial_probe(struct platform_device *pdev)
 {
-	struct arc_uart_port *uart;
-	int rc;
+	int rc, dev_id;
+	struct device_node *np = pdev->dev.of_node;
+
+	/* no device tree device */
+	if (!np)
+		return -ENODEV;
 
-	if (is_early_platform_device(pdev))
-		return arc_serial_probe_earlyprintk(pdev);
+	dev_id = of_alias_get_id(np, "serial");
+	if (dev_id < 0)
+		dev_id = 0;
 
-	uart = &arc_uart_ports[pdev->id];
-	rc = arc_uart_init_one(pdev, uart);
+	rc = arc_uart_init_one(pdev, dev_id);
 	if (rc)
 		return rc;
 
-	return uart_add_one_port(&arc_uart_driver, &uart->port);
+	rc = uart_add_one_port(&arc_uart_driver, &arc_uart_ports[dev_id].port);
+	return rc;
 }
 
 static int arc_serial_remove(struct platform_device *pdev)
@@ -695,16 +711,32 @@ static int arc_serial_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static const struct of_device_id arc_uart_dt_ids[] = {
+	{ .compatible = "snps,arc-uart" },
+	{ /* Sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, arc_uart_dt_ids);
+
 static struct platform_driver arc_platform_driver = {
 	.probe = arc_serial_probe,
 	.remove = arc_serial_remove,
 	.driver = {
 		.name = DRIVER_NAME,
 		.owner = THIS_MODULE,
+		.of_match_table  = arc_uart_dt_ids,
 	 },
 };
 
 #ifdef CONFIG_SERIAL_ARC_CONSOLE
+
+static struct platform_driver early_arc_platform_driver __initdata = {
+	.probe = arc_serial_probe_earlyprintk,
+	.remove = arc_serial_remove,
+	.driver = {
+		.name = DRIVER_NAME,
+		.owner = THIS_MODULE,
+	 },
+};
 /*
  * Register an early platform driver of "earlyprintk" class.
  * ARCH platform code installs the driver and probes the early devices
@@ -712,7 +744,7 @@ static struct platform_driver arc_platform_driver = {
  * or it could be done independently, for all "earlyprintk" class drivers.
  * [see arch/arc/plat-arcfpga/platform.c]
  */
-early_platform_init("earlyprintk", &arc_platform_driver);
+early_platform_init("earlyprintk", &early_arc_platform_driver);
 
 #endif  /* CONFIG_SERIAL_ARC_CONSOLE */
 
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 922e85aeb63..d4a7c241b75 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -774,14 +774,14 @@ static void atmel_rx_from_ring(struct uart_port *port)
 	 * uart_start(), which takes the lock.
 	 */
 	spin_unlock(&port->lock);
-	tty_flip_buffer_push(port->state->port.tty);
+	tty_flip_buffer_push(&port->state->port);
 	spin_lock(&port->lock);
 }
 
 static void atmel_rx_from_dma(struct uart_port *port)
 {
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
-	struct tty_struct *tty = port->state->port.tty;
+	struct tty_port *tport = &port->state->port;
 	struct atmel_dma_buffer *pdc;
 	int rx_idx = atmel_port->pdc_rx_idx;
 	unsigned int head;
@@ -820,7 +820,8 @@ static void atmel_rx_from_dma(struct uart_port *port)
 			 */
 			count = head - tail;
 
-			tty_insert_flip_string(tty, pdc->buf + pdc->ofs, count);
+			tty_insert_flip_string(tport, pdc->buf + pdc->ofs,
+						count);
 
 			dma_sync_single_for_device(port->dev, pdc->dma_addr,
 					pdc->dma_size, DMA_FROM_DEVICE);
@@ -848,7 +849,7 @@ static void atmel_rx_from_dma(struct uart_port *port)
 	 * uart_start(), which takes the lock.
 	 */
 	spin_unlock(&port->lock);
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(tport);
 	spin_lock(&port->lock);
 
 	UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
diff --git a/drivers/tty/serial/bcm63xx_uart.c b/drivers/tty/serial/bcm63xx_uart.c
index c76a226080f..719594e5fc2 100644
--- a/drivers/tty/serial/bcm63xx_uart.c
+++ b/drivers/tty/serial/bcm63xx_uart.c
@@ -235,14 +235,13 @@ static const char *bcm_uart_type(struct uart_port *port)
  */
 static void bcm_uart_do_rx(struct uart_port *port)
 {
-	struct tty_struct *tty;
+	struct tty_port *port = &port->state->port;
 	unsigned int max_count;
 
 	/* limit number of char read in interrupt, should not be
 	 * higher than fifo size anyway since we're much faster than
 	 * serial port */
 	max_count = 32;
-	tty = port->state->port.tty;
 	do {
 		unsigned int iestat, c, cstat;
 		char flag;
@@ -261,7 +260,7 @@ static void bcm_uart_do_rx(struct uart_port *port)
 			bcm_uart_writel(port, val, UART_CTL_REG);
 
 			port->icount.overrun++;
-			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+			tty_insert_flip_char(port, 0, TTY_OVERRUN);
 		}
 
 		if (!(iestat & UART_IR_STAT(UART_IR_RXNOTEMPTY)))
@@ -300,11 +299,11 @@ static void bcm_uart_do_rx(struct uart_port *port)
 
 
 		if ((cstat & port->ignore_status_mask) == 0)
-			tty_insert_flip_char(tty, c, flag);
+			tty_insert_flip_char(port, c, flag);
 
 	} while (--max_count);
 
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(port);
 }
 
 /*
diff --git a/drivers/tty/serial/bfin_sport_uart.c b/drivers/tty/serial/bfin_sport_uart.c
index f5d117379b6..487c173b0f7 100644
--- a/drivers/tty/serial/bfin_sport_uart.c
+++ b/drivers/tty/serial/bfin_sport_uart.c
@@ -149,7 +149,7 @@ static int sport_uart_setup(struct sport_uart_port *up, int size, int baud_rate)
 static irqreturn_t sport_uart_rx_irq(int irq, void *dev_id)
 {
 	struct sport_uart_port *up = dev_id;
-	struct tty_struct *tty = up->port.state->port.tty;
+	struct tty_port *port = &up->port.state->port;
 	unsigned int ch;
 
 	spin_lock(&up->port.lock);
@@ -159,9 +159,10 @@ static irqreturn_t sport_uart_rx_irq(int irq, void *dev_id)
 		up->port.icount.rx++;
 
 		if (!uart_handle_sysrq_char(&up->port, ch))
-			tty_insert_flip_char(tty, ch, TTY_NORMAL);
+			tty_insert_flip_char(port, ch, TTY_NORMAL);
 	}
-	tty_flip_buffer_push(tty);
+	/* XXX this won't deadlock with lowlat? */
+	tty_flip_buffer_push(port);
 
 	spin_unlock(&up->port.lock);
 
@@ -182,7 +183,6 @@ static irqreturn_t sport_uart_tx_irq(int irq, void *dev_id)
 static irqreturn_t sport_uart_err_irq(int irq, void *dev_id)
 {
 	struct sport_uart_port *up = dev_id;
-	struct tty_struct *tty = up->port.state->port.tty;
 	unsigned int stat = SPORT_GET_STAT(up);
 
 	spin_lock(&up->port.lock);
@@ -190,7 +190,7 @@ static irqreturn_t sport_uart_err_irq(int irq, void *dev_id)
 	/* Overflow in RX FIFO */
 	if (stat & ROVF) {
 		up->port.icount.overrun++;
-		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+		tty_insert_flip_char(&up->port.state->port, 0, TTY_OVERRUN);
 		SPORT_PUT_STAT(up, ROVF); /* Clear ROVF bit */
 	}
 	/* These should not happen */
@@ -205,6 +205,8 @@ static irqreturn_t sport_uart_err_irq(int irq, void *dev_id)
 	SSYNC();
 
 	spin_unlock(&up->port.lock);
+	/* XXX we don't push the overrun bit to TTY? */
+
 	return IRQ_HANDLED;
 }
 
diff --git a/drivers/tty/serial/bfin_uart.c b/drivers/tty/serial/bfin_uart.c
index 2e2b2c1cb72..12dceda9db3 100644
--- a/drivers/tty/serial/bfin_uart.c
+++ b/drivers/tty/serial/bfin_uart.c
@@ -223,7 +223,6 @@ static void bfin_serial_enable_ms(struct uart_port *port)
 #ifdef CONFIG_SERIAL_BFIN_PIO
 static void bfin_serial_rx_chars(struct bfin_serial_port *uart)
 {
-	struct tty_struct *tty = NULL;
 	unsigned int status, ch, flg;
 	static struct timeval anomaly_start = { .tv_sec = 0 };
 
@@ -242,11 +241,9 @@ static void bfin_serial_rx_chars(struct bfin_serial_port *uart)
 			return;
 		}
 
-	if (!uart->port.state || !uart->port.state->port.tty)
+	if (!uart->port.state)
 		return;
 #endif
-	tty = uart->port.state->port.tty;
-
 	if (ANOMALY_05000363) {
 		/* The BF533 (and BF561) family of processors have a nice anomaly
 		 * where they continuously generate characters for a "single" break.
@@ -325,7 +322,7 @@ static void bfin_serial_rx_chars(struct bfin_serial_port *uart)
 	uart_insert_char(&uart->port, status, OE, ch, flg);
 
  ignore_char:
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&uart->port.state->port);
 }
 
 static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
@@ -426,7 +423,6 @@ static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
 
 static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
 {
-	struct tty_struct *tty = uart->port.state->port.tty;
 	int i, flg, status;
 
 	status = UART_GET_LSR(uart);
@@ -471,7 +467,7 @@ static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
 	}
 
  dma_ignore_char:
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&uart->port.state->port);
 }
 
 void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
diff --git a/drivers/tty/serial/clps711x.c b/drivers/tty/serial/clps711x.c
index 3fd2526d121..bfb17968c8d 100644
--- a/drivers/tty/serial/clps711x.c
+++ b/drivers/tty/serial/clps711x.c
@@ -85,12 +85,8 @@ static void uart_clps711x_enable_ms(struct uart_port *port)
 static irqreturn_t uart_clps711x_int_rx(int irq, void *dev_id)
 {
 	struct uart_port *port = dev_id;
-	struct tty_struct *tty = tty_port_tty_get(&port->state->port);
 	unsigned int status, ch, flg;
 
-	if (!tty)
-		return IRQ_HANDLED;
-
 	for (;;) {
 		status = clps_readl(SYSFLG(port));
 		if (status & SYSFLG_URXFE)
@@ -130,9 +126,7 @@ static irqreturn_t uart_clps711x_int_rx(int irq, void *dev_id)
 		uart_insert_char(port, status, UARTDR_OVERR, ch, flg);
 	}
 
-	tty_flip_buffer_push(tty);
-
-	tty_kref_put(tty);
+	tty_flip_buffer_push(&port->state->port);
 
 	return IRQ_HANDLED;
 }
diff --git a/drivers/tty/serial/cpm_uart/cpm_uart_core.c b/drivers/tty/serial/cpm_uart/cpm_uart_core.c
index ad0caf17680..97f4e185864 100644
--- a/drivers/tty/serial/cpm_uart/cpm_uart_core.c
+++ b/drivers/tty/serial/cpm_uart/cpm_uart_core.c
@@ -245,7 +245,7 @@ static void cpm_uart_int_rx(struct uart_port *port)
 	int i;
 	unsigned char ch;
 	u8 *cp;
-	struct tty_struct *tty = port->state->port.tty;
+	struct tty_port *tport = &port->state->port;
 	struct uart_cpm_port *pinfo = (struct uart_cpm_port *)port;
 	cbd_t __iomem *bdp;
 	u16 status;
@@ -276,7 +276,7 @@ static void cpm_uart_int_rx(struct uart_port *port)
 		/* If we have not enough room in tty flip buffer, then we try
 		 * later, which will be the next rx-interrupt or a timeout
 		 */
-		if(tty_buffer_request_room(tty, i) < i) {
+		if (tty_buffer_request_room(tport, i) < i) {
 			printk(KERN_WARNING "No room in flip buffer\n");
 			return;
 		}
@@ -302,7 +302,7 @@ static void cpm_uart_int_rx(struct uart_port *port)
 			}
 #endif
 		      error_return:
-			tty_insert_flip_char(tty, ch, flg);
+			tty_insert_flip_char(tport, ch, flg);
 
 		}		/* End while (i--) */
 
@@ -322,7 +322,7 @@ static void cpm_uart_int_rx(struct uart_port *port)
 	pinfo->rx_cur = bdp;
 
 	/* activate BH processing */
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(tport);
 
 	return;
 
@@ -507,7 +507,7 @@ static void cpm_uart_set_termios(struct uart_port *port,
 
 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
 	if (baud < HW_BUF_SPD_THRESHOLD ||
-	    (pinfo->port.state && pinfo->port.state->port.tty->low_latency))
+	    (pinfo->port.state && pinfo->port.state->port.low_latency))
 		pinfo->rx_fifosize = 1;
 	else
 		pinfo->rx_fifosize = RX_BUF_SIZE;
diff --git a/drivers/tty/serial/crisv10.c b/drivers/tty/serial/crisv10.c
index 35ee6a2c687..5f37c31e32b 100644
--- a/drivers/tty/serial/crisv10.c
+++ b/drivers/tty/serial/crisv10.c
@@ -1760,8 +1760,7 @@ add_char_and_flag(struct e100_serial *info, unsigned char data, unsigned char fl
 
 		info->icount.rx++;
 	} else {
-		struct tty_struct *tty = info->port.tty;
-		tty_insert_flip_char(tty, data, flag);
+		tty_insert_flip_char(&info->port, data, flag);
 		info->icount.rx++;
 	}
 
@@ -2105,22 +2104,15 @@ static int force_eop_if_needed(struct e100_serial *info)
 
 static void flush_to_flip_buffer(struct e100_serial *info)
 {
-	struct tty_struct *tty;
 	struct etrax_recv_buffer *buffer;
 	unsigned long flags;
 
 	local_irq_save(flags);
-	tty = info->port.tty;
-
-	if (!tty) {
-		local_irq_restore(flags);
-		return;
-	}
 
 	while ((buffer = info->first_recv_buffer) != NULL) {
 		unsigned int count = buffer->length;
 
-		tty_insert_flip_string(tty, buffer->buffer, count);
+		tty_insert_flip_string(&info->port, buffer->buffer, count);
 		info->recv_cnt -= count;
 
 		if (count == buffer->length) {
@@ -2139,7 +2131,7 @@ static void flush_to_flip_buffer(struct e100_serial *info)
 	local_irq_restore(flags);
 
 	/* This includes a check for low-latency */
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&info->port);
 }
 
 static void check_flush_timeout(struct e100_serial *info)
@@ -2275,12 +2267,6 @@ static
 struct e100_serial * handle_ser_rx_interrupt_no_dma(struct e100_serial *info)
 {
 	unsigned long data_read;
-	struct tty_struct *tty = info->port.tty;
-
-	if (!tty) {
-		printk("!NO TTY!\n");
-		return info;
-	}
 
 	/* Read data and status at the same time */
 	data_read = *((unsigned long *)&info->ioport[REG_DATA_STATUS32]);
@@ -2338,8 +2324,7 @@ more_data:
 					data_in, data_read);
 				char flag = TTY_NORMAL;
 				if (info->errorcode == ERRCODE_INSERT_BREAK) {
-					struct tty_struct *tty = info->port.tty;
-					tty_insert_flip_char(tty, 0, flag);
+					tty_insert_flip_char(&info->port, 0, flag);
 					info->icount.rx++;
 				}
 
@@ -2353,7 +2338,7 @@ more_data:
 					info->icount.frame++;
 					flag = TTY_FRAME;
 				}
-				tty_insert_flip_char(tty, data, flag);
+				tty_insert_flip_char(&info->port, data, flag);
 				info->errorcode = 0;
 			}
 			info->break_detected_cnt = 0;
@@ -2369,7 +2354,7 @@ more_data:
 			log_int(rdpc(), 0, 0);
 		}
 		);
-		tty_insert_flip_char(tty,
+		tty_insert_flip_char(&info->port,
 			IO_EXTRACT(R_SERIAL0_READ, data_in, data_read),
 			TTY_NORMAL);
 	} else {
@@ -2384,7 +2369,7 @@ more_data:
 		goto more_data;
 	}
 
-	tty_flip_buffer_push(info->port.tty);
+	tty_flip_buffer_push(&info->port);
 	return info;
 }
 
@@ -3137,7 +3122,7 @@ static int rs_raw_write(struct tty_struct *tty,
 
 	/* first some sanity checks */
 
-	if (!tty || !info->xmit.buf)
+	if (!info->xmit.buf)
 		return 0;
 
 #ifdef SERIAL_DEBUG_DATA
@@ -3464,7 +3449,7 @@ set_serial_info(struct e100_serial *info,
 	info->type = new_serial.type;
 	info->close_delay = new_serial.close_delay;
 	info->closing_wait = new_serial.closing_wait;
-	info->port.tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
+	info->port.low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 
  check_and_exit:
 	if (info->flags & ASYNC_INITIALIZED) {
@@ -4108,7 +4093,7 @@ rs_open(struct tty_struct *tty, struct file * filp)
 	tty->driver_data = info;
 	info->port.tty = tty;
 
-	tty->low_latency = !!(info->flags & ASYNC_LOW_LATENCY);
+	info->port.low_latency = !!(info->flags & ASYNC_LOW_LATENCY);
 
 	/*
 	 * If the port is in the middle of closing, bail out now
diff --git a/drivers/tty/serial/dz.c b/drivers/tty/serial/dz.c
index 6491b8644a7..2f2b2e538a5 100644
--- a/drivers/tty/serial/dz.c
+++ b/drivers/tty/serial/dz.c
@@ -187,7 +187,6 @@ static inline void dz_receive_chars(struct dz_mux *mux)
 {
 	struct uart_port *uport;
 	struct dz_port *dport = &mux->dport[0];
-	struct tty_struct *tty = NULL;
 	struct uart_icount *icount;
 	int lines_rx[DZ_NB_PORT] = { [0 ... DZ_NB_PORT - 1] = 0 };
 	unsigned char ch, flag;
@@ -197,7 +196,6 @@ static inline void dz_receive_chars(struct dz_mux *mux)
 	while ((status = dz_in(dport, DZ_RBUF)) & DZ_DVAL) {
 		dport = &mux->dport[LINE(status)];
 		uport = &dport->port;
-		tty = uport->state->port.tty;	/* point to the proper dev */
 
 		ch = UCHAR(status);		/* grab the char */
 		flag = TTY_NORMAL;
@@ -249,7 +247,7 @@ static inline void dz_receive_chars(struct dz_mux *mux)
 	}
 	for (i = 0; i < DZ_NB_PORT; i++)
 		if (lines_rx[i])
-			tty_flip_buffer_push(mux->dport[i].port.state->port.tty);
+			tty_flip_buffer_push(&mux->dport[i].port.state->port);
 }
 
 /*
diff --git a/drivers/tty/serial/efm32-uart.c b/drivers/tty/serial/efm32-uart.c
index a8cbb267052..7d199c8e1a7 100644
--- a/drivers/tty/serial/efm32-uart.c
+++ b/drivers/tty/serial/efm32-uart.c
@@ -81,6 +81,7 @@ struct efm32_uart_port {
 	struct uart_port port;
 	unsigned int txirq;
 	struct clk *clk;
+	struct efm32_uart_pdata pdata;
 };
 #define to_efm_port(_port) container_of(_port, struct efm32_uart_port, port)
 #define efm_debug(efm_port, format, arg...)			\
@@ -194,8 +195,7 @@ static void efm32_uart_break_ctl(struct uart_port *port, int ctl)
 	/* not possible without fiddling with gpios */
 }
 
-static void efm32_uart_rx_chars(struct efm32_uart_port *efm_port,
-		struct tty_struct *tty)
+static void efm32_uart_rx_chars(struct efm32_uart_port *efm_port)
 {
 	struct uart_port *port = &efm_port->port;
 
@@ -237,8 +237,8 @@ static void efm32_uart_rx_chars(struct efm32_uart_port *efm_port,
 					rxdata & UARTn_RXDATAX_RXDATA__MASK))
 			continue;
 
-		if (tty && (rxdata & port->ignore_status_mask) == 0)
-			tty_insert_flip_char(tty,
+		if ((rxdata & port->ignore_status_mask) == 0)
+			tty_insert_flip_char(&port->state->port,
 					rxdata & UARTn_RXDATAX_RXDATA__MASK, flag);
 	}
 }
@@ -249,15 +249,13 @@ static irqreturn_t efm32_uart_rxirq(int irq, void *data)
 	u32 irqflag = efm32_uart_read32(efm_port, UARTn_IF);
 	int handled = IRQ_NONE;
 	struct uart_port *port = &efm_port->port;
-	struct tty_struct *tty;
+	struct tty_port *tport = &port->state->port;
 
 	spin_lock(&port->lock);
 
-	tty = tty_kref_get(port->state->port.tty);
-
 	if (irqflag & UARTn_IF_RXDATAV) {
 		efm32_uart_write32(efm_port, UARTn_IF_RXDATAV, UARTn_IFC);
-		efm32_uart_rx_chars(efm_port, tty);
+		efm32_uart_rx_chars(efm_port);
 
 		handled = IRQ_HANDLED;
 	}
@@ -265,16 +263,12 @@ static irqreturn_t efm32_uart_rxirq(int irq, void *data)
 	if (irqflag & UARTn_IF_RXOF) {
 		efm32_uart_write32(efm_port, UARTn_IF_RXOF, UARTn_IFC);
 		port->icount.overrun++;
-		if (tty)
-			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 
 		handled = IRQ_HANDLED;
 	}
 
-	if (tty) {
-		tty_flip_buffer_push(tty);
-		tty_kref_put(tty);
-	}
+	tty_flip_buffer_push(tport);
 
 	spin_unlock(&port->lock);
 
@@ -300,13 +294,8 @@ static irqreturn_t efm32_uart_txirq(int irq, void *data)
 static int efm32_uart_startup(struct uart_port *port)
 {
 	struct efm32_uart_port *efm_port = to_efm_port(port);
-	u32 location = 0;
-	struct efm32_uart_pdata *pdata = dev_get_platdata(port->dev);
 	int ret;
 
-	if (pdata)
-		location = UARTn_ROUTE_LOCATION(pdata->location);
-
 	ret = clk_enable(efm_port->clk);
 	if (ret) {
 		efm_debug(efm_port, "failed to enable clk\n");
@@ -315,7 +304,9 @@ static int efm32_uart_startup(struct uart_port *port)
 	port->uartclk = clk_get_rate(efm_port->clk);
 
 	/* Enable pins at configured location */
-	efm32_uart_write32(efm_port, location | UARTn_ROUTE_RXPEN | UARTn_ROUTE_TXPEN,
+	efm32_uart_write32(efm_port,
+			UARTn_ROUTE_LOCATION(efm_port->pdata.location) |
+			UARTn_ROUTE_RXPEN | UARTn_ROUTE_TXPEN,
 			UARTn_ROUTE);
 
 	ret = request_irq(port->irq, efm32_uart_rxirq, 0,
@@ -674,11 +665,24 @@ static int efm32_uart_probe_dt(struct platform_device *pdev,
 		struct efm32_uart_port *efm_port)
 {
 	struct device_node *np = pdev->dev.of_node;
+	u32 location;
 	int ret;
 
 	if (!np)
 		return 1;
 
+	ret = of_property_read_u32(np, "location", &location);
+	if (!ret) {
+		if (location > 5) {
+			dev_err(&pdev->dev, "invalid location\n");
+			return -EINVAL;
+		}
+		efm_debug(efm_port, "using location %u\n", location);
+		efm_port->pdata.location = location;
+	} else {
+		efm_debug(efm_port, "fall back to location 0\n");
+	}
+
 	ret = of_alias_get_id(np, "serial");
 	if (ret < 0) {
 		dev_err(&pdev->dev, "failed to get alias id: %d\n", ret);
@@ -738,10 +742,16 @@ static int efm32_uart_probe(struct platform_device *pdev)
 	efm_port->port.flags = UPF_BOOT_AUTOCONF;
 
 	ret = efm32_uart_probe_dt(pdev, efm_port);
-	if (ret > 0)
+	if (ret > 0) {
 		/* not created by device tree */
+		const struct efm32_uart_pdata *pdata = dev_get_platdata(&pdev->dev);
+
 		efm_port->port.line = pdev->id;
 
+		if (pdata)
+			efm_port->pdata = *pdata;
+	}
+
 	if (efm_port->port.line >= 0 &&
 			efm_port->port.line < ARRAY_SIZE(efm32_uart_ports))
 		efm32_uart_ports[efm_port->port.line] = efm_port;
diff --git a/drivers/tty/serial/icom.c b/drivers/tty/serial/icom.c
index 72b6334bcf1..bc9e6b017b0 100644
--- a/drivers/tty/serial/icom.c
+++ b/drivers/tty/serial/icom.c
@@ -734,7 +734,7 @@ static void xmit_interrupt(u16 port_int_reg, struct icom_port *icom_port)
 static void recv_interrupt(u16 port_int_reg, struct icom_port *icom_port)
 {
 	short int count, rcv_buff;
-	struct tty_struct *tty = icom_port->uart_port.state->port.tty;
+	struct tty_port *port = &icom_port->uart_port.state->port;
 	unsigned short int status;
 	struct uart_icount *icount;
 	unsigned long offset;
@@ -761,7 +761,7 @@ static void recv_interrupt(u16 port_int_reg, struct icom_port *icom_port)
 		/* Block copy all but the last byte as this may have status */
 		if (count > 0) {
 			first = icom_port->recv_buf[offset];
-			tty_insert_flip_string(tty, icom_port->recv_buf + offset, count - 1);
+			tty_insert_flip_string(port, icom_port->recv_buf + offset, count - 1);
 		}
 
 		icount = &icom_port->uart_port.icount;
@@ -812,7 +812,7 @@ static void recv_interrupt(u16 port_int_reg, struct icom_port *icom_port)
 
 		}
 
-		tty_insert_flip_char(tty, *(icom_port->recv_buf + offset + count - 1), flag);
+		tty_insert_flip_char(port, *(icom_port->recv_buf + offset + count - 1), flag);
 
 		if (status & SA_FLAGS_OVERRUN)
 			/*
@@ -820,7 +820,7 @@ static void recv_interrupt(u16 port_int_reg, struct icom_port *icom_port)
 			 * reported immediately, and doesn't
 			 * affect the current character
 			 */
-			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+			tty_insert_flip_char(port, 0, TTY_OVERRUN);
 ignore_char:
 		icom_port->statStg->rcv[rcv_buff].flags = 0;
 		icom_port->statStg->rcv[rcv_buff].leLength = 0;
@@ -834,7 +834,7 @@ ignore_char:
 		status = cpu_to_le16(icom_port->statStg->rcv[rcv_buff].flags);
 	}
 	icom_port->next_rcv = rcv_buff;
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(port);
 }
 
 static void process_interrupt(u16 port_int_reg,
diff --git a/drivers/tty/serial/ifx6x60.c b/drivers/tty/serial/ifx6x60.c
index 8cb6d8d66a1..68d7ce997ed 100644
--- a/drivers/tty/serial/ifx6x60.c
+++ b/drivers/tty/serial/ifx6x60.c
@@ -481,7 +481,6 @@ static int ifx_spi_prepare_tx_buffer(struct ifx_spi_device *ifx_dev)
 	unsigned char *tx_buffer;
 
 	tx_buffer = ifx_dev->tx_buffer;
-	memset(tx_buffer, 0, IFX_SPI_TRANSFER_SIZE);
 
 	/* make room for required SPI header */
 	tx_buffer += IFX_SPI_HEADER_OVERHEAD;
@@ -615,7 +614,7 @@ static int ifx_port_activate(struct tty_port *port, struct tty_struct *tty)
 	tty->driver_data = ifx_dev;
 
 	/* allows flip string push from int context */
-	tty->low_latency = 1;
+	port->low_latency = 1;
 
 	/* set flag to allows data transfer */
 	set_bit(IFX_SPI_STATE_IO_AVAILABLE, &ifx_dev->flags);
@@ -670,12 +669,8 @@ static const struct tty_operations ifx_spi_serial_ops = {
 static void ifx_spi_insert_flip_string(struct ifx_spi_device *ifx_dev,
 				    unsigned char *chars, size_t size)
 {
-	struct tty_struct *tty = tty_port_tty_get(&ifx_dev->tty_port);
-	if (!tty)
-		return;
-	tty_insert_flip_string(tty, chars, size);
-	tty_flip_buffer_push(tty);
-	tty_kref_put(tty);
+	tty_insert_flip_string(&ifx_dev->tty_port, chars, size);
+	tty_flip_buffer_push(&ifx_dev->tty_port);
 }
 
 /**
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 59819121fe9..147c9e19359 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -48,8 +48,8 @@
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/pinctrl/consumer.h>
+#include <linux/io.h>
 
-#include <asm/io.h>
 #include <asm/irq.h>
 #include <linux/platform_data/serial-imx.h>
 
@@ -73,102 +73,102 @@
 #define IMX21_UTS 0xb4 /* UART Test Register on all other i.mx*/
 
 /* UART Control Register Bit Fields.*/
-#define  URXD_CHARRDY    (1<<15)
-#define  URXD_ERR        (1<<14)
-#define  URXD_OVRRUN     (1<<13)
-#define  URXD_FRMERR     (1<<12)
-#define  URXD_BRK        (1<<11)
-#define  URXD_PRERR      (1<<10)
-#define  UCR1_ADEN       (1<<15) /* Auto detect interrupt */
-#define  UCR1_ADBR       (1<<14) /* Auto detect baud rate */
-#define  UCR1_TRDYEN     (1<<13) /* Transmitter ready interrupt enable */
-#define  UCR1_IDEN       (1<<12) /* Idle condition interrupt */
-#define  UCR1_RRDYEN     (1<<9)	 /* Recv ready interrupt enable */
-#define  UCR1_RDMAEN     (1<<8)	 /* Recv ready DMA enable */
-#define  UCR1_IREN       (1<<7)	 /* Infrared interface enable */
-#define  UCR1_TXMPTYEN   (1<<6)	 /* Transimitter empty interrupt enable */
-#define  UCR1_RTSDEN     (1<<5)	 /* RTS delta interrupt enable */
-#define  UCR1_SNDBRK     (1<<4)	 /* Send break */
-#define  UCR1_TDMAEN     (1<<3)	 /* Transmitter ready DMA enable */
-#define  IMX1_UCR1_UARTCLKEN  (1<<2)  /* UART clock enabled, i.mx1 only */
-#define  UCR1_DOZE       (1<<1)	 /* Doze */
-#define  UCR1_UARTEN     (1<<0)	 /* UART enabled */
-#define  UCR2_ESCI     	 (1<<15) /* Escape seq interrupt enable */
-#define  UCR2_IRTS  	 (1<<14) /* Ignore RTS pin */
-#define  UCR2_CTSC  	 (1<<13) /* CTS pin control */
-#define  UCR2_CTS        (1<<12) /* Clear to send */
-#define  UCR2_ESCEN      (1<<11) /* Escape enable */
-#define  UCR2_PREN       (1<<8)  /* Parity enable */
-#define  UCR2_PROE       (1<<7)  /* Parity odd/even */
-#define  UCR2_STPB       (1<<6)	 /* Stop */
-#define  UCR2_WS         (1<<5)	 /* Word size */
-#define  UCR2_RTSEN      (1<<4)	 /* Request to send interrupt enable */
-#define  UCR2_ATEN       (1<<3)  /* Aging Timer Enable */
-#define  UCR2_TXEN       (1<<2)	 /* Transmitter enabled */
-#define  UCR2_RXEN       (1<<1)	 /* Receiver enabled */
-#define  UCR2_SRST 	 (1<<0)	 /* SW reset */
-#define  UCR3_DTREN 	 (1<<13) /* DTR interrupt enable */
-#define  UCR3_PARERREN   (1<<12) /* Parity enable */
-#define  UCR3_FRAERREN   (1<<11) /* Frame error interrupt enable */
-#define  UCR3_DSR        (1<<10) /* Data set ready */
-#define  UCR3_DCD        (1<<9)  /* Data carrier detect */
-#define  UCR3_RI         (1<<8)  /* Ring indicator */
-#define  UCR3_TIMEOUTEN  (1<<7)  /* Timeout interrupt enable */
-#define  UCR3_RXDSEN	 (1<<6)  /* Receive status interrupt enable */
-#define  UCR3_AIRINTEN   (1<<5)  /* Async IR wake interrupt enable */
-#define  UCR3_AWAKEN	 (1<<4)  /* Async wake interrupt enable */
-#define  IMX21_UCR3_RXDMUXSEL	 (1<<2)  /* RXD Muxed Input Select */
-#define  UCR3_INVT  	 (1<<1)  /* Inverted Infrared transmission */
-#define  UCR3_BPEN  	 (1<<0)  /* Preset registers enable */
-#define  UCR4_CTSTL_SHF  10      /* CTS trigger level shift */
-#define  UCR4_CTSTL_MASK 0x3F    /* CTS trigger is 6 bits wide */
-#define  UCR4_INVR  	 (1<<9)  /* Inverted infrared reception */
-#define  UCR4_ENIRI 	 (1<<8)  /* Serial infrared interrupt enable */
-#define  UCR4_WKEN  	 (1<<7)  /* Wake interrupt enable */
-#define  UCR4_REF16 	 (1<<6)  /* Ref freq 16 MHz */
-#define  UCR4_IRSC  	 (1<<5)  /* IR special case */
-#define  UCR4_TCEN  	 (1<<3)  /* Transmit complete interrupt enable */
-#define  UCR4_BKEN  	 (1<<2)  /* Break condition interrupt enable */
-#define  UCR4_OREN  	 (1<<1)  /* Receiver overrun interrupt enable */
-#define  UCR4_DREN  	 (1<<0)  /* Recv data ready interrupt enable */
-#define  UFCR_RXTL_SHF   0       /* Receiver trigger level shift */
-#define  UFCR_DCEDTE	 (1<<6)  /* DCE/DTE mode select */
-#define  UFCR_RFDIV      (7<<7)  /* Reference freq divider mask */
-#define  UFCR_RFDIV_REG(x)	(((x) < 7 ? 6 - (x) : 6) << 7)
-#define  UFCR_TXTL_SHF   10      /* Transmitter trigger level shift */
-#define  USR1_PARITYERR  (1<<15) /* Parity error interrupt flag */
-#define  USR1_RTSS  	 (1<<14) /* RTS pin status */
-#define  USR1_TRDY  	 (1<<13) /* Transmitter ready interrupt/dma flag */
-#define  USR1_RTSD  	 (1<<12) /* RTS delta */
-#define  USR1_ESCF  	 (1<<11) /* Escape seq interrupt flag */
-#define  USR1_FRAMERR    (1<<10) /* Frame error interrupt flag */
-#define  USR1_RRDY       (1<<9)	 /* Receiver ready interrupt/dma flag */
-#define  USR1_TIMEOUT    (1<<7)	 /* Receive timeout interrupt status */
-#define  USR1_RXDS  	 (1<<6)	 /* Receiver idle interrupt flag */
-#define  USR1_AIRINT	 (1<<5)	 /* Async IR wake interrupt flag */
-#define  USR1_AWAKE 	 (1<<4)	 /* Aysnc wake interrupt flag */
-#define  USR2_ADET  	 (1<<15) /* Auto baud rate detect complete */
-#define  USR2_TXFE  	 (1<<14) /* Transmit buffer FIFO empty */
-#define  USR2_DTRF  	 (1<<13) /* DTR edge interrupt flag */
-#define  USR2_IDLE  	 (1<<12) /* Idle condition */
-#define  USR2_IRINT 	 (1<<8)	 /* Serial infrared interrupt flag */
-#define  USR2_WAKE  	 (1<<7)	 /* Wake */
-#define  USR2_RTSF  	 (1<<4)	 /* RTS edge interrupt flag */
-#define  USR2_TXDC  	 (1<<3)	 /* Transmitter complete */
-#define  USR2_BRCD  	 (1<<2)	 /* Break condition */
-#define  USR2_ORE        (1<<1)	 /* Overrun error */
-#define  USR2_RDR        (1<<0)	 /* Recv data ready */
-#define  UTS_FRCPERR	 (1<<13) /* Force parity error */
-#define  UTS_LOOP        (1<<12) /* Loop tx and rx */
-#define  UTS_TXEMPTY	 (1<<6)	 /* TxFIFO empty */
-#define  UTS_RXEMPTY	 (1<<5)	 /* RxFIFO empty */
-#define  UTS_TXFULL 	 (1<<4)	 /* TxFIFO full */
-#define  UTS_RXFULL 	 (1<<3)	 /* RxFIFO full */
-#define  UTS_SOFTRST	 (1<<0)	 /* Software reset */
+#define URXD_CHARRDY	(1<<15)
+#define URXD_ERR	(1<<14)
+#define URXD_OVRRUN	(1<<13)
+#define URXD_FRMERR	(1<<12)
+#define URXD_BRK	(1<<11)
+#define URXD_PRERR	(1<<10)
+#define UCR1_ADEN	(1<<15) /* Auto detect interrupt */
+#define UCR1_ADBR	(1<<14) /* Auto detect baud rate */
+#define UCR1_TRDYEN	(1<<13) /* Transmitter ready interrupt enable */
+#define UCR1_IDEN	(1<<12) /* Idle condition interrupt */
+#define UCR1_RRDYEN	(1<<9)	/* Recv ready interrupt enable */
+#define UCR1_RDMAEN	(1<<8)	/* Recv ready DMA enable */
+#define UCR1_IREN	(1<<7)	/* Infrared interface enable */
+#define UCR1_TXMPTYEN	(1<<6)	/* Transimitter empty interrupt enable */
+#define UCR1_RTSDEN	(1<<5)	/* RTS delta interrupt enable */
+#define UCR1_SNDBRK	(1<<4)	/* Send break */
+#define UCR1_TDMAEN	(1<<3)	/* Transmitter ready DMA enable */
+#define IMX1_UCR1_UARTCLKEN (1<<2) /* UART clock enabled, i.mx1 only */
+#define UCR1_DOZE	(1<<1)	/* Doze */
+#define UCR1_UARTEN	(1<<0)	/* UART enabled */
+#define UCR2_ESCI	(1<<15)	/* Escape seq interrupt enable */
+#define UCR2_IRTS	(1<<14)	/* Ignore RTS pin */
+#define UCR2_CTSC	(1<<13)	/* CTS pin control */
+#define UCR2_CTS	(1<<12)	/* Clear to send */
+#define UCR2_ESCEN	(1<<11)	/* Escape enable */
+#define UCR2_PREN	(1<<8)	/* Parity enable */
+#define UCR2_PROE	(1<<7)	/* Parity odd/even */
+#define UCR2_STPB	(1<<6)	/* Stop */
+#define UCR2_WS		(1<<5)	/* Word size */
+#define UCR2_RTSEN	(1<<4)	/* Request to send interrupt enable */
+#define UCR2_ATEN	(1<<3)	/* Aging Timer Enable */
+#define UCR2_TXEN	(1<<2)	/* Transmitter enabled */
+#define UCR2_RXEN	(1<<1)	/* Receiver enabled */
+#define UCR2_SRST	(1<<0)	/* SW reset */
+#define UCR3_DTREN	(1<<13) /* DTR interrupt enable */
+#define UCR3_PARERREN	(1<<12) /* Parity enable */
+#define UCR3_FRAERREN	(1<<11) /* Frame error interrupt enable */
+#define UCR3_DSR	(1<<10) /* Data set ready */
+#define UCR3_DCD	(1<<9)	/* Data carrier detect */
+#define UCR3_RI		(1<<8)	/* Ring indicator */
+#define UCR3_TIMEOUTEN	(1<<7)	/* Timeout interrupt enable */
+#define UCR3_RXDSEN	(1<<6)	/* Receive status interrupt enable */
+#define UCR3_AIRINTEN	(1<<5)	/* Async IR wake interrupt enable */
+#define UCR3_AWAKEN	(1<<4)	/* Async wake interrupt enable */
+#define IMX21_UCR3_RXDMUXSEL	(1<<2)	/* RXD Muxed Input Select */
+#define UCR3_INVT	(1<<1)	/* Inverted Infrared transmission */
+#define UCR3_BPEN	(1<<0)	/* Preset registers enable */
+#define UCR4_CTSTL_SHF	10	/* CTS trigger level shift */
+#define UCR4_CTSTL_MASK	0x3F	/* CTS trigger is 6 bits wide */
+#define UCR4_INVR	(1<<9)	/* Inverted infrared reception */
+#define UCR4_ENIRI	(1<<8)	/* Serial infrared interrupt enable */
+#define UCR4_WKEN	(1<<7)	/* Wake interrupt enable */
+#define UCR4_REF16	(1<<6)	/* Ref freq 16 MHz */
+#define UCR4_IRSC	(1<<5)	/* IR special case */
+#define UCR4_TCEN	(1<<3)	/* Transmit complete interrupt enable */
+#define UCR4_BKEN	(1<<2)	/* Break condition interrupt enable */
+#define UCR4_OREN	(1<<1)	/* Receiver overrun interrupt enable */
+#define UCR4_DREN	(1<<0)	/* Recv data ready interrupt enable */
+#define UFCR_RXTL_SHF	0	/* Receiver trigger level shift */
+#define UFCR_DCEDTE	(1<<6)	/* DCE/DTE mode select */
+#define UFCR_RFDIV	(7<<7)	/* Reference freq divider mask */
+#define UFCR_RFDIV_REG(x)	(((x) < 7 ? 6 - (x) : 6) << 7)
+#define UFCR_TXTL_SHF	10	/* Transmitter trigger level shift */
+#define USR1_PARITYERR	(1<<15) /* Parity error interrupt flag */
+#define USR1_RTSS	(1<<14) /* RTS pin status */
+#define USR1_TRDY	(1<<13) /* Transmitter ready interrupt/dma flag */
+#define USR1_RTSD	(1<<12) /* RTS delta */
+#define USR1_ESCF	(1<<11) /* Escape seq interrupt flag */
+#define USR1_FRAMERR	(1<<10) /* Frame error interrupt flag */
+#define USR1_RRDY	(1<<9)	 /* Receiver ready interrupt/dma flag */
+#define USR1_TIMEOUT	(1<<7)	 /* Receive timeout interrupt status */
+#define USR1_RXDS	 (1<<6)	 /* Receiver idle interrupt flag */
+#define USR1_AIRINT	 (1<<5)	 /* Async IR wake interrupt flag */
+#define USR1_AWAKE	 (1<<4)	 /* Aysnc wake interrupt flag */
+#define USR2_ADET	 (1<<15) /* Auto baud rate detect complete */
+#define USR2_TXFE	 (1<<14) /* Transmit buffer FIFO empty */
+#define USR2_DTRF	 (1<<13) /* DTR edge interrupt flag */
+#define USR2_IDLE	 (1<<12) /* Idle condition */
+#define USR2_IRINT	 (1<<8)	 /* Serial infrared interrupt flag */
+#define USR2_WAKE	 (1<<7)	 /* Wake */
+#define USR2_RTSF	 (1<<4)	 /* RTS edge interrupt flag */
+#define USR2_TXDC	 (1<<3)	 /* Transmitter complete */
+#define USR2_BRCD	 (1<<2)	 /* Break condition */
+#define USR2_ORE	(1<<1)	 /* Overrun error */
+#define USR2_RDR	(1<<0)	 /* Recv data ready */
+#define UTS_FRCPERR	(1<<13) /* Force parity error */
+#define UTS_LOOP	(1<<12)	 /* Loop tx and rx */
+#define UTS_TXEMPTY	 (1<<6)	 /* TxFIFO empty */
+#define UTS_RXEMPTY	 (1<<5)	 /* RxFIFO empty */
+#define UTS_TXFULL	 (1<<4)	 /* TxFIFO full */
+#define UTS_RXFULL	 (1<<3)	 /* RxFIFO full */
+#define UTS_SOFTRST	 (1<<0)	 /* Software reset */
 
 /* We've been assigned a range on the "Low-density serial ports" major */
-#define SERIAL_IMX_MAJOR        207
-#define MINOR_START	        16
+#define SERIAL_IMX_MAJOR	207
+#define MINOR_START		16
 #define DEV_NAME		"ttymxc"
 
 /*
@@ -199,7 +199,7 @@ struct imx_port {
 	struct uart_port	port;
 	struct timer_list	timer;
 	unsigned int		old_status;
-	int			txirq,rxirq,rtsirq;
+	int			txirq, rxirq, rtsirq;
 	unsigned int		have_rtscts:1;
 	unsigned int		use_irda:1;
 	unsigned int		irda_inv_rx:1;
@@ -397,7 +397,7 @@ static void imx_stop_rx(struct uart_port *port)
 	unsigned long temp;
 
 	temp = readl(sport->port.membase + UCR2);
-	writel(temp &~ UCR2_RXEN, sport->port.membase + UCR2);
+	writel(temp & ~UCR2_RXEN, sport->port.membase + UCR2);
 }
 
 /*
@@ -490,9 +490,8 @@ static irqreturn_t imx_txint(int irq, void *dev_id)
 	struct circ_buf *xmit = &sport->port.state->xmit;
 	unsigned long flags;
 
-	spin_lock_irqsave(&sport->port.lock,flags);
-	if (sport->port.x_char)
-	{
+	spin_lock_irqsave(&sport->port.lock, flags);
+	if (sport->port.x_char) {
 		/* Send next char */
 		writel(sport->port.x_char, sport->port.membase + URTX0);
 		goto out;
@@ -509,18 +508,18 @@ static irqreturn_t imx_txint(int irq, void *dev_id)
 		uart_write_wakeup(&sport->port);
 
 out:
-	spin_unlock_irqrestore(&sport->port.lock,flags);
+	spin_unlock_irqrestore(&sport->port.lock, flags);
 	return IRQ_HANDLED;
 }
 
 static irqreturn_t imx_rxint(int irq, void *dev_id)
 {
 	struct imx_port *sport = dev_id;
-	unsigned int rx,flg,ignored = 0;
-	struct tty_struct *tty = sport->port.state->port.tty;
+	unsigned int rx, flg, ignored = 0;
+	struct tty_port *port = &sport->port.state->port;
 	unsigned long flags, temp;
 
-	spin_lock_irqsave(&sport->port.lock,flags);
+	spin_lock_irqsave(&sport->port.lock, flags);
 
 	while (readl(sport->port.membase + USR2) & USR2_RDR) {
 		flg = TTY_NORMAL;
@@ -570,12 +569,12 @@ static irqreturn_t imx_rxint(int irq, void *dev_id)
 #endif
 		}
 
-		tty_insert_flip_char(tty, rx, flg);
+		tty_insert_flip_char(port, rx, flg);
 	}
 
 out:
-	spin_unlock_irqrestore(&sport->port.lock,flags);
-	tty_flip_buffer_push(tty);
+	spin_unlock_irqrestore(&sport->port.lock, flags);
+	tty_flip_buffer_push(port);
 	return IRQ_HANDLED;
 }
 
@@ -654,7 +653,7 @@ static void imx_break_ctl(struct uart_port *port, int break_state)
 
 	temp = readl(sport->port.membase + UCR1) & ~UCR1_SNDBRK;
 
-	if ( break_state != 0 )
+	if (break_state != 0)
 		temp |= UCR1_SNDBRK;
 
 	writel(temp, sport->port.membase + UCR1);
@@ -696,8 +695,8 @@ static int imx_startup(struct uart_port *port)
 		temp |= UCR4_IRSC;
 
 	/* set the trigger level for CTS */
-	temp &= ~(UCR4_CTSTL_MASK<<  UCR4_CTSTL_SHF);
-	temp |= CTSTL<<  UCR4_CTSTL_SHF;
+	temp &= ~(UCR4_CTSTL_MASK << UCR4_CTSTL_SHF);
+	temp |= CTSTL << UCR4_CTSTL_SHF;
 
 	writel(temp & ~UCR4_DREN, sport->port.membase + UCR4);
 
@@ -799,7 +798,7 @@ static int imx_startup(struct uart_port *port)
 	 * Enable modem status interrupts
 	 */
 	imx_enable_ms(&sport->port);
-	spin_unlock_irqrestore(&sport->port.lock,flags);
+	spin_unlock_irqrestore(&sport->port.lock, flags);
 
 	if (USE_IRDA(sport)) {
 		struct imxuart_platform_data *pdata;
@@ -909,7 +908,7 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios,
 		ucr2 = UCR2_SRST | UCR2_IRTS;
 
 	if (termios->c_cflag & CRTSCTS) {
-		if( sport->have_rtscts ) {
+		if (sport->have_rtscts) {
 			ucr2 &= ~UCR2_IRTS;
 			ucr2 |= UCR2_CTSC;
 		} else {
@@ -969,12 +968,12 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios,
 	writel(old_ucr1 & ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN),
 			sport->port.membase + UCR1);
 
-	while ( !(readl(sport->port.membase + USR2) & USR2_TXDC))
+	while (!(readl(sport->port.membase + USR2) & USR2_TXDC))
 		barrier();
 
 	/* then, disable everything */
 	old_txrxen = readl(sport->port.membase + UCR2);
-	writel(old_txrxen & ~( UCR2_TXEN | UCR2_RXEN),
+	writel(old_txrxen & ~(UCR2_TXEN | UCR2_RXEN),
 			sport->port.membase + UCR2);
 	old_txrxen &= (UCR2_TXEN | UCR2_RXEN);
 
@@ -1212,9 +1211,15 @@ imx_console_write(struct console *co, const char *s, unsigned int count)
 	struct imx_port *sport = imx_ports[co->index];
 	struct imx_port_ucrs old_ucr;
 	unsigned int ucr1;
-	unsigned long flags;
+	unsigned long flags = 0;
+	int locked = 1;
 
-	spin_lock_irqsave(&sport->port.lock, flags);
+	if (sport->port.sysrq)
+		locked = 0;
+	else if (oops_in_progress)
+		locked = spin_trylock_irqsave(&sport->port.lock, flags);
+	else
+		spin_lock_irqsave(&sport->port.lock, flags);
 
 	/*
 	 *	First, save UCR1/2/3 and then disable interrupts
@@ -1241,7 +1246,8 @@ imx_console_write(struct console *co, const char *s, unsigned int count)
 
 	imx_port_ucrs_restore(&sport->port, &old_ucr);
 
-	spin_unlock_irqrestore(&sport->port.lock, flags);
+	if (locked)
+		spin_unlock_irqrestore(&sport->port.lock, flags);
 }
 
 /*
@@ -1255,7 +1261,7 @@ imx_console_get_options(struct imx_port *sport, int *baud,
 
 	if (readl(sport->port.membase + UCR1) & UCR1_UARTEN) {
 		/* ok, the port was enabled */
-		unsigned int ucr2, ubir,ubmr, uartclk;
+		unsigned int ucr2, ubir, ubmr, uartclk;
 		unsigned int baud_raw;
 		unsigned int ucfr_rfdiv;
 
@@ -1301,8 +1307,8 @@ imx_console_get_options(struct imx_port *sport, int *baud,
 			*baud = (baud_raw + 50) / 100 * 100;
 		}
 
-		if(*baud != baud_raw)
-			printk(KERN_INFO "Serial: Console IMX rounded baud rate from %d to %d\n",
+		if (*baud != baud_raw)
+			pr_info("Console IMX rounded baud rate from %d to %d\n",
 				baud_raw, *baud);
 	}
 }
@@ -1324,7 +1330,7 @@ imx_console_setup(struct console *co, char *options)
 	if (co->index == -1 || co->index >= ARRAY_SIZE(imx_ports))
 		co->index = 0;
 	sport = imx_ports[co->index];
-	if(sport == NULL)
+	if (sport == NULL)
 		return -ENODEV;
 
 	if (options)
@@ -1462,7 +1468,7 @@ static int serial_imx_probe(struct platform_device *pdev)
 	struct resource *res;
 	struct pinctrl *pinctrl;
 
-	sport = kzalloc(sizeof(*sport), GFP_KERNEL);
+	sport = devm_kzalloc(&pdev->dev, sizeof(*sport), GFP_KERNEL);
 	if (!sport)
 		return -ENOMEM;
 
@@ -1470,19 +1476,15 @@ static int serial_imx_probe(struct platform_device *pdev)
 	if (ret > 0)
 		serial_imx_probe_pdata(sport, pdev);
 	else if (ret < 0)
-		goto free;
+		return ret;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res) {
-		ret = -ENODEV;
-		goto free;
-	}
+	if (!res)
+		return -ENODEV;
 
-	base = ioremap(res->start, PAGE_SIZE);
-	if (!base) {
-		ret = -ENOMEM;
-		goto free;
-	}
+	base = devm_ioremap(&pdev->dev, res->start, PAGE_SIZE);
+	if (!base)
+		return -ENOMEM;
 
 	sport->port.dev = &pdev->dev;
 	sport->port.mapbase = res->start;
@@ -1504,21 +1506,21 @@ static int serial_imx_probe(struct platform_device *pdev)
 	if (IS_ERR(pinctrl)) {
 		ret = PTR_ERR(pinctrl);
 		dev_err(&pdev->dev, "failed to get default pinctrl: %d\n", ret);
-		goto unmap;
+		return ret;
 	}
 
 	sport->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
 	if (IS_ERR(sport->clk_ipg)) {
 		ret = PTR_ERR(sport->clk_ipg);
 		dev_err(&pdev->dev, "failed to get ipg clk: %d\n", ret);
-		goto unmap;
+		return ret;
 	}
 
 	sport->clk_per = devm_clk_get(&pdev->dev, "per");
 	if (IS_ERR(sport->clk_per)) {
 		ret = PTR_ERR(sport->clk_per);
 		dev_err(&pdev->dev, "failed to get per clk: %d\n", ret);
-		goto unmap;
+		return ret;
 	}
 
 	clk_prepare_enable(sport->clk_per);
@@ -1547,11 +1549,6 @@ deinit:
 clkput:
 	clk_disable_unprepare(sport->clk_per);
 	clk_disable_unprepare(sport->clk_ipg);
-unmap:
-	iounmap(sport->port.membase);
-free:
-	kfree(sport);
-
 	return ret;
 }
 
@@ -1572,9 +1569,6 @@ static int serial_imx_remove(struct platform_device *pdev)
 	if (pdata && pdata->exit)
 		pdata->exit(pdev);
 
-	iounmap(sport->port.membase);
-	kfree(sport);
-
 	return 0;
 }
 
@@ -1596,7 +1590,7 @@ static int __init imx_serial_init(void)
 {
 	int ret;
 
-	printk(KERN_INFO "Serial: IMX driver\n");
+	pr_info("Serial: IMX driver\n");
 
 	ret = uart_register_driver(&imx_reg);
 	if (ret)
diff --git a/drivers/tty/serial/ioc3_serial.c b/drivers/tty/serial/ioc3_serial.c
index d8f1d1d5447..6e4c715c5d2 100644
--- a/drivers/tty/serial/ioc3_serial.c
+++ b/drivers/tty/serial/ioc3_serial.c
@@ -1000,7 +1000,7 @@ ioc3_change_speed(struct uart_port *the_port,
 
 	the_port->ignore_status_mask = N_ALL_INPUT;
 
-	state->port.tty->low_latency = 1;
+	state->port.low_latency = 1;
 
 	if (iflag & IGNPAR)
 		the_port->ignore_status_mask &= ~(N_PARITY_ERROR
@@ -1393,7 +1393,6 @@ static inline int do_read(struct uart_port *the_port, char *buf, int len)
  */
 static int receive_chars(struct uart_port *the_port)
 {
-	struct tty_struct *tty;
 	unsigned char ch[MAX_CHARS];
 	int read_count = 0, read_room, flip = 0;
 	struct uart_state *state = the_port->state;
@@ -1403,25 +1402,23 @@ static int receive_chars(struct uart_port *the_port)
 	/* Make sure all the pointers are "good" ones */
 	if (!state)
 		return 0;
-	if (!state->port.tty)
-		return 0;
 
 	if (!(port->ip_flags & INPUT_ENABLE))
 		return 0;
 
 	spin_lock_irqsave(&the_port->lock, pflags);
-	tty = state->port.tty;
 
 	read_count = do_read(the_port, ch, MAX_CHARS);
 	if (read_count > 0) {
 		flip = 1;
-		read_room = tty_insert_flip_string(tty, ch, read_count);
+		read_room = tty_insert_flip_string(&state->port, ch,
+				read_count);
 		the_port->icount.rx += read_count;
 	}
 	spin_unlock_irqrestore(&the_port->lock, pflags);
 
 	if (flip)
-		tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(&state->port);
 
 	return read_count;
 }
diff --git a/drivers/tty/serial/ioc4_serial.c b/drivers/tty/serial/ioc4_serial.c
index 3e7da10cebb..e2520abcb1c 100644
--- a/drivers/tty/serial/ioc4_serial.c
+++ b/drivers/tty/serial/ioc4_serial.c
@@ -1740,7 +1740,7 @@ ioc4_change_speed(struct uart_port *the_port,
 
 	the_port->ignore_status_mask = N_ALL_INPUT;
 
-	state->port.tty->low_latency = 1;
+	state->port.low_latency = 1;
 
 	if (iflag & IGNPAR)
 		the_port->ignore_status_mask &= ~(N_PARITY_ERROR
@@ -2340,7 +2340,6 @@ static inline int do_read(struct uart_port *the_port, unsigned char *buf,
  */
 static void receive_chars(struct uart_port *the_port)
 {
-	struct tty_struct *tty;
 	unsigned char ch[IOC4_MAX_CHARS];
 	int read_count, request_count = IOC4_MAX_CHARS;
 	struct uart_icount *icount;
@@ -2350,26 +2349,23 @@ static void receive_chars(struct uart_port *the_port)
 	/* Make sure all the pointers are "good" ones */
 	if (!state)
 		return;
-	if (!state->port.tty)
-		return;
 
 	spin_lock_irqsave(&the_port->lock, pflags);
-	tty = state->port.tty;
 
-	request_count = tty_buffer_request_room(tty, IOC4_MAX_CHARS);
+	request_count = tty_buffer_request_room(&state->port, IOC4_MAX_CHARS);
 
 	if (request_count > 0) {
 		icount = &the_port->icount;
 		read_count = do_read(the_port, ch, request_count);
 		if (read_count > 0) {
-			tty_insert_flip_string(tty, ch, read_count);
+			tty_insert_flip_string(&state->port, ch, read_count);
 			icount->rx += read_count;
 		}
 	}
 
 	spin_unlock_irqrestore(&the_port->lock, pflags);
 
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&state->port);
 }
 
 /**
@@ -2883,6 +2879,7 @@ ioc4_serial_attach_one(struct ioc4_driver_data *idd)
 	/* error exits that give back resources */
 out5:
 	ioc4_serial_remove_one(idd);
+	return ret;
 out4:
 	kfree(soft);
 out3:
diff --git a/drivers/tty/serial/ip22zilog.c b/drivers/tty/serial/ip22zilog.c
index 7b1cda59ebb..cb3c81eb099 100644
--- a/drivers/tty/serial/ip22zilog.c
+++ b/drivers/tty/serial/ip22zilog.c
@@ -248,17 +248,12 @@ static void ip22zilog_maybe_update_regs(struct uart_ip22zilog_port *up,
 #define Rx_BRK 0x0100                   /* BREAK event software flag.  */
 #define Rx_SYS 0x0200                   /* SysRq event software flag.  */
 
-static struct tty_struct *ip22zilog_receive_chars(struct uart_ip22zilog_port *up,
+static bool ip22zilog_receive_chars(struct uart_ip22zilog_port *up,
 						  struct zilog_channel *channel)
 {
-	struct tty_struct *tty;
 	unsigned char ch, flag;
 	unsigned int r1;
-
-	tty = NULL;
-	if (up->port.state != NULL &&
-	    up->port.state->port.tty != NULL)
-		tty = up->port.state->port.tty;
+	bool push = up->port.state != NULL;
 
 	for (;;) {
 		ch = readb(&channel->control);
@@ -312,10 +307,10 @@ static struct tty_struct *ip22zilog_receive_chars(struct uart_ip22zilog_port *up
 		if (uart_handle_sysrq_char(&up->port, ch))
 			continue;
 
-		if (tty)
+		if (push)
 			uart_insert_char(&up->port, r1, Rx_OVR, ch, flag);
 	}
-	return tty;
+	return push;
 }
 
 static void ip22zilog_status_handle(struct uart_ip22zilog_port *up,
@@ -438,21 +433,20 @@ static irqreturn_t ip22zilog_interrupt(int irq, void *dev_id)
 	while (up) {
 		struct zilog_channel *channel
 			= ZILOG_CHANNEL_FROM_PORT(&up->port);
-		struct tty_struct *tty;
 		unsigned char r3;
+		bool push = false;
 
 		spin_lock(&up->port.lock);
 		r3 = read_zsreg(channel, R3);
 
 		/* Channel A */
-		tty = NULL;
 		if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
 			writeb(RES_H_IUS, &channel->control);
 			ZSDELAY();
 			ZS_WSYNC(channel);
 
 			if (r3 & CHARxIP)
-				tty = ip22zilog_receive_chars(up, channel);
+				push = ip22zilog_receive_chars(up, channel);
 			if (r3 & CHAEXT)
 				ip22zilog_status_handle(up, channel);
 			if (r3 & CHATxIP)
@@ -460,22 +454,22 @@ static irqreturn_t ip22zilog_interrupt(int irq, void *dev_id)
 		}
 		spin_unlock(&up->port.lock);
 
-		if (tty)
-			tty_flip_buffer_push(tty);
+		if (push)
+			tty_flip_buffer_push(&up->port.state->port);
 
 		/* Channel B */
 		up = up->next;
 		channel = ZILOG_CHANNEL_FROM_PORT(&up->port);
+		push = false;
 
 		spin_lock(&up->port.lock);
-		tty = NULL;
 		if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
 			writeb(RES_H_IUS, &channel->control);
 			ZSDELAY();
 			ZS_WSYNC(channel);
 
 			if (r3 & CHBRxIP)
-				tty = ip22zilog_receive_chars(up, channel);
+				push = ip22zilog_receive_chars(up, channel);
 			if (r3 & CHBEXT)
 				ip22zilog_status_handle(up, channel);
 			if (r3 & CHBTxIP)
@@ -483,8 +477,8 @@ static irqreturn_t ip22zilog_interrupt(int irq, void *dev_id)
 		}
 		spin_unlock(&up->port.lock);
 
-		if (tty)
-			tty_flip_buffer_push(tty);
+		if (push)
+			tty_flip_buffer_push(&up->port.state->port);
 
 		up = up->next;
 	}
diff --git a/drivers/tty/serial/jsm/jsm_tty.c b/drivers/tty/serial/jsm/jsm_tty.c
index 4c00c5550b1..00f250ae14c 100644
--- a/drivers/tty/serial/jsm/jsm_tty.c
+++ b/drivers/tty/serial/jsm/jsm_tty.c
@@ -521,6 +521,7 @@ void jsm_input(struct jsm_channel *ch)
 {
 	struct jsm_board *bd;
 	struct tty_struct *tp;
+	struct tty_port *port;
 	u32 rmask;
 	u16 head;
 	u16 tail;
@@ -536,7 +537,8 @@ void jsm_input(struct jsm_channel *ch)
 	if (!ch)
 		return;
 
-	tp = ch->uart_port.state->port.tty;
+	port = &ch->uart_port.state->port;
+	tp = port->tty;
 
 	bd = ch->ch_bd;
 	if(!bd)
@@ -600,7 +602,7 @@ void jsm_input(struct jsm_channel *ch)
 		return;
 	}
 
-	len = tty_buffer_request_room(tp, data_len);
+	len = tty_buffer_request_room(port, data_len);
 	n = len;
 
 	/*
@@ -629,16 +631,16 @@ void jsm_input(struct jsm_channel *ch)
 				 * format it likes.
 				 */
 				if (*(ch->ch_equeue +tail +i) & UART_LSR_BI)
-					tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i),  TTY_BREAK);
+					tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i),  TTY_BREAK);
 				else if (*(ch->ch_equeue +tail +i) & UART_LSR_PE)
-					tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i), TTY_PARITY);
+					tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_PARITY);
 				else if (*(ch->ch_equeue +tail +i) & UART_LSR_FE)
-					tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i), TTY_FRAME);
+					tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_FRAME);
 				else
-					tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i), TTY_NORMAL);
+					tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_NORMAL);
 			}
 		} else {
-			tty_insert_flip_string(tp, ch->ch_rqueue + tail, s) ;
+			tty_insert_flip_string(port, ch->ch_rqueue + tail, s);
 		}
 		tail += s;
 		n -= s;
@@ -652,7 +654,7 @@ void jsm_input(struct jsm_channel *ch)
 	spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 
 	/* Tell the tty layer its okay to "eat" the data now */
-	tty_flip_buffer_push(tp);
+	tty_flip_buffer_push(port);
 
 	jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "finish\n");
 }
diff --git a/drivers/tty/serial/kgdb_nmi.c b/drivers/tty/serial/kgdb_nmi.c
index 6ac2b797a76..5dafcf1c227 100644
--- a/drivers/tty/serial/kgdb_nmi.c
+++ b/drivers/tty/serial/kgdb_nmi.c
@@ -23,6 +23,7 @@
 #include <linux/tty.h>
 #include <linux/tty_driver.h>
 #include <linux/tty_flip.h>
+#include <linux/serial_core.h>
 #include <linux/interrupt.h>
 #include <linux/hrtimer.h>
 #include <linux/tick.h>
@@ -202,7 +203,6 @@ bool kgdb_nmi_poll_knock(void)
 static void kgdb_nmi_tty_receiver(unsigned long data)
 {
 	struct kgdb_nmi_tty_priv *priv = (void *)data;
-	struct tty_struct *tty;
 	char ch;
 
 	tasklet_schedule(&priv->tlet);
@@ -210,16 +210,9 @@ static void kgdb_nmi_tty_receiver(unsigned long data)
 	if (likely(!kgdb_nmi_tty_enabled || !kfifo_len(&priv->fifo)))
 		return;
 
-	/* Port is there, but tty might be hung up, check. */
-	tty = tty_port_tty_get(kgdb_nmi_port);
-	if (!tty)
-		return;
-
 	while (kfifo_out(&priv->fifo, &ch, 1))
-		tty_insert_flip_char(priv->port.tty, ch, TTY_NORMAL);
-	tty_flip_buffer_push(priv->port.tty);
-
-	tty_kref_put(tty);
+		tty_insert_flip_char(&priv->port, ch, TTY_NORMAL);
+	tty_flip_buffer_push(&priv->port);
 }
 
 static int kgdb_nmi_tty_activate(struct tty_port *port, struct tty_struct *tty)
diff --git a/drivers/tty/serial/lantiq.c b/drivers/tty/serial/lantiq.c
index 02da071fe1e..15733da757c 100644
--- a/drivers/tty/serial/lantiq.c
+++ b/drivers/tty/serial/lantiq.c
@@ -162,21 +162,16 @@ lqasc_enable_ms(struct uart_port *port)
 static int
 lqasc_rx_chars(struct uart_port *port)
 {
-	struct tty_struct *tty = tty_port_tty_get(&port->state->port);
+	struct tty_port *tport = &port->state->port;
 	unsigned int ch = 0, rsr = 0, fifocnt;
 
-	if (!tty) {
-		dev_dbg(port->dev, "%s:tty is busy now", __func__);
-		return -EBUSY;
-	}
-	fifocnt =
-		ltq_r32(port->membase + LTQ_ASC_FSTAT) & ASCFSTAT_RXFFLMASK;
+	fifocnt = ltq_r32(port->membase + LTQ_ASC_FSTAT) & ASCFSTAT_RXFFLMASK;
 	while (fifocnt--) {
 		u8 flag = TTY_NORMAL;
 		ch = ltq_r8(port->membase + LTQ_ASC_RBUF);
 		rsr = (ltq_r32(port->membase + LTQ_ASC_STATE)
 			& ASCSTATE_ANY) | UART_DUMMY_UER_RX;
-		tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(tport);
 		port->icount.rx++;
 
 		/*
@@ -208,7 +203,7 @@ lqasc_rx_chars(struct uart_port *port)
 		}
 
 		if ((rsr & port->ignore_status_mask) == 0)
-			tty_insert_flip_char(tty, ch, flag);
+			tty_insert_flip_char(tport, ch, flag);
 
 		if (rsr & ASCSTATE_ROE)
 			/*
@@ -216,11 +211,12 @@ lqasc_rx_chars(struct uart_port *port)
 			 * immediately, and doesn't affect the current
 			 * character
 			 */
-			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+			tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 	}
+
 	if (ch != 0)
-		tty_flip_buffer_push(tty);
-	tty_kref_put(tty);
+		tty_flip_buffer_push(tport);
+
 	return 0;
 }
 
diff --git a/drivers/tty/serial/lpc32xx_hs.c b/drivers/tty/serial/lpc32xx_hs.c
index 0e86bff3fe2..dffea6b2cd7 100644
--- a/drivers/tty/serial/lpc32xx_hs.c
+++ b/drivers/tty/serial/lpc32xx_hs.c
@@ -257,17 +257,8 @@ static void __serial_uart_flush(struct uart_port *port)
 
 static void __serial_lpc32xx_rx(struct uart_port *port)
 {
+	struct tty_port *tport = &port->state->port;
 	unsigned int tmp, flag;
-	struct tty_struct *tty = tty_port_tty_get(&port->state->port);
-
-	if (!tty) {
-		/* Discard data: no tty available */
-		while (!(readl(LPC32XX_HSUART_FIFO(port->membase)) &
-			 LPC32XX_HSU_RX_EMPTY))
-			;
-
-		return;
-	}
 
 	/* Read data from FIFO and push into terminal */
 	tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
@@ -281,15 +272,14 @@ static void __serial_lpc32xx_rx(struct uart_port *port)
 			       LPC32XX_HSUART_IIR(port->membase));
 			port->icount.frame++;
 			flag = TTY_FRAME;
-			tty_insert_flip_char(tty, 0, TTY_FRAME);
+			tty_insert_flip_char(tport, 0, TTY_FRAME);
 		}
 
-		tty_insert_flip_char(tty, (tmp & 0xFF), flag);
+		tty_insert_flip_char(tport, (tmp & 0xFF), flag);
 
 		tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
 	}
-	tty_flip_buffer_push(tty);
-	tty_kref_put(tty);
+	tty_flip_buffer_push(tport);
 }
 
 static void __serial_lpc32xx_tx(struct uart_port *port)
@@ -332,7 +322,7 @@ exit_tx:
 static irqreturn_t serial_lpc32xx_interrupt(int irq, void *dev_id)
 {
 	struct uart_port *port = dev_id;
-	struct tty_struct *tty = tty_port_tty_get(&port->state->port);
+	struct tty_port *tport = &port->state->port;
 	u32 status;
 
 	spin_lock(&port->lock);
@@ -356,17 +346,14 @@ static irqreturn_t serial_lpc32xx_interrupt(int irq, void *dev_id)
 		writel(LPC32XX_HSU_RX_OE_INT,
 		       LPC32XX_HSUART_IIR(port->membase));
 		port->icount.overrun++;
-		if (tty) {
-			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
-			tty_schedule_flip(tty);
-		}
+		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
+		tty_schedule_flip(tport);
 	}
 
 	/* Data received? */
 	if (status & (LPC32XX_HSU_RX_TIMEOUT_INT | LPC32XX_HSU_RX_TRIG_INT)) {
 		__serial_lpc32xx_rx(port);
-		if (tty)
-			tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(tport);
 	}
 
 	/* Transmit data request? */
@@ -376,7 +363,6 @@ static irqreturn_t serial_lpc32xx_interrupt(int irq, void *dev_id)
 	}
 
 	spin_unlock(&port->lock);
-	tty_kref_put(tty);
 
 	return IRQ_HANDLED;
 }
diff --git a/drivers/tty/serial/m32r_sio.c b/drivers/tty/serial/m32r_sio.c
index b13949ad340..bb1afa0922e 100644
--- a/drivers/tty/serial/m32r_sio.c
+++ b/drivers/tty/serial/m32r_sio.c
@@ -300,7 +300,7 @@ static void m32r_sio_enable_ms(struct uart_port *port)
 
 static void receive_chars(struct uart_sio_port *up, int *status)
 {
-	struct tty_struct *tty = up->port.state->port.tty;
+	struct tty_port *port = &up->port.state->port;
 	unsigned char ch;
 	unsigned char flag;
 	int max_count = 256;
@@ -355,7 +355,7 @@ static void receive_chars(struct uart_sio_port *up, int *status)
 		if (uart_handle_sysrq_char(&up->port, ch))
 			goto ignore_char;
 		if ((*status & up->port.ignore_status_mask) == 0)
-			tty_insert_flip_char(tty, ch, flag);
+			tty_insert_flip_char(port, ch, flag);
 
 		if (*status & UART_LSR_OE) {
 			/*
@@ -363,12 +363,12 @@ static void receive_chars(struct uart_sio_port *up, int *status)
 			 * immediately, and doesn't affect the current
 			 * character.
 			 */
-			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+			tty_insert_flip_char(port, 0, TTY_OVERRUN);
 		}
 	ignore_char:
 		*status = serial_in(up, UART_LSR);
 	} while ((*status & UART_LSR_DR) && (max_count-- > 0));
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(port);
 }
 
 static void transmit_chars(struct uart_sio_port *up)
diff --git a/drivers/tty/serial/max3100.c b/drivers/tty/serial/max3100.c
index dd6277eb5a3..32517d4bcea 100644
--- a/drivers/tty/serial/max3100.c
+++ b/drivers/tty/serial/max3100.c
@@ -310,8 +310,8 @@ static void max3100_work(struct work_struct *w)
 			}
 		}
 
-		if (rxchars > 16 && s->port.state->port.tty != NULL) {
-			tty_flip_buffer_push(s->port.state->port.tty);
+		if (rxchars > 16) {
+			tty_flip_buffer_push(&s->port.state->port);
 			rxchars = 0;
 		}
 		if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
@@ -323,8 +323,8 @@ static void max3100_work(struct work_struct *w)
 		  (!uart_circ_empty(xmit) &&
 		   !uart_tx_stopped(&s->port))));
 
-	if (rxchars > 0 && s->port.state->port.tty != NULL)
-		tty_flip_buffer_push(s->port.state->port.tty);
+	if (rxchars > 0)
+		tty_flip_buffer_push(&s->port.state->port);
 }
 
 static irqreturn_t max3100_irq(int irqno, void *dev_id)
@@ -529,7 +529,7 @@ max3100_set_termios(struct uart_port *port, struct ktermios *termios,
 			MAX3100_STATUS_OE;
 
 	/* we are sending char from a workqueue so enable */
-	s->port.state->port.tty->low_latency = 1;
+	s->port.state->port.low_latency = 1;
 
 	if (s->poll_time > 0)
 		del_timer_sync(&s->timer);
diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c
index a801f6872ca..0c2422cb04e 100644
--- a/drivers/tty/serial/max310x.c
+++ b/drivers/tty/serial/max310x.c
@@ -460,10 +460,6 @@ static int max310x_set_ref_clk(struct max310x_port *s)
 static void max310x_handle_rx(struct max310x_port *s, unsigned int rxlen)
 {
 	unsigned int sts = 0, ch = 0, flag;
-	struct tty_struct *tty = tty_port_tty_get(&s->port.state->port);
-
-	if (!tty)
-		return;
 
 	if (unlikely(rxlen >= MAX310X_FIFO_SIZE)) {
 		dev_warn(s->port.dev, "Possible RX FIFO overrun %d\n", rxlen);
@@ -516,9 +512,7 @@ static void max310x_handle_rx(struct max310x_port *s, unsigned int rxlen)
 				 ch, flag);
 	}
 
-	tty_flip_buffer_push(tty);
-
-	tty_kref_put(tty);
+	tty_flip_buffer_push(&s->port.state->port);
 }
 
 static void max310x_handle_tx(struct max310x_port *s)
diff --git a/drivers/tty/serial/mcf.c b/drivers/tty/serial/mcf.c
index fcd56ab6053..e956377a38f 100644
--- a/drivers/tty/serial/mcf.c
+++ b/drivers/tty/serial/mcf.c
@@ -23,6 +23,7 @@
 #include <linux/serial.h>
 #include <linux/serial_core.h>
 #include <linux/io.h>
+#include <linux/uaccess.h>
 #include <asm/coldfire.h>
 #include <asm/mcfsim.h>
 #include <asm/mcfuart.h>
@@ -55,6 +56,7 @@ struct mcf_uart {
 	struct uart_port	port;
 	unsigned int		sigs;		/* Local copy of line sigs */
 	unsigned char		imr;		/* Local IMR mirror */
+	struct serial_rs485	rs485;		/* RS485 settings */
 };
 
 /****************************************************************************/
@@ -101,6 +103,12 @@ static void mcf_start_tx(struct uart_port *port)
 {
 	struct mcf_uart *pp = container_of(port, struct mcf_uart, port);
 
+	if (pp->rs485.flags & SER_RS485_ENABLED) {
+		/* Enable Transmitter */
+		writeb(MCFUART_UCR_TXENABLE, port->membase + MCFUART_UCR);
+		/* Manually assert RTS */
+		writeb(MCFUART_UOP_RTS, port->membase + MCFUART_UOP1);
+	}
 	pp->imr |= MCFUART_UIR_TXREADY;
 	writeb(pp->imr, port->membase + MCFUART_UIMR);
 }
@@ -196,6 +204,7 @@ static void mcf_shutdown(struct uart_port *port)
 static void mcf_set_termios(struct uart_port *port, struct ktermios *termios,
 	struct ktermios *old)
 {
+	struct mcf_uart *pp = container_of(port, struct mcf_uart, port);
 	unsigned long flags;
 	unsigned int baud, baudclk;
 #if defined(CONFIG_M5272)
@@ -248,6 +257,11 @@ static void mcf_set_termios(struct uart_port *port, struct ktermios *termios,
 		mr2 |= MCFUART_MR2_TXCTS;
 	}
 
+	if (pp->rs485.flags & SER_RS485_ENABLED) {
+		dev_dbg(port->dev, "Setting UART to RS485\n");
+		mr2 |= MCFUART_MR2_TXRTS;
+	}
+
 	spin_lock_irqsave(&port->lock, flags);
 	uart_update_timeout(port, termios->c_cflag, baud);
 	writeb(MCFUART_UCR_CMDRESETRX, port->membase + MCFUART_UCR);
@@ -310,7 +324,7 @@ static void mcf_rx_chars(struct mcf_uart *pp)
 		uart_insert_char(port, status, MCFUART_USR_RXOVERRUN, ch, flag);
 	}
 
-	tty_flip_buffer_push(port->state->port.tty);
+	tty_flip_buffer_push(&port->state->port);
 }
 
 /****************************************************************************/
@@ -342,6 +356,10 @@ static void mcf_tx_chars(struct mcf_uart *pp)
 	if (xmit->head == xmit->tail) {
 		pp->imr &= ~MCFUART_UIR_TXREADY;
 		writeb(pp->imr, port->membase + MCFUART_UIMR);
+		/* Disable TX to negate RTS automatically */
+		if (pp->rs485.flags & SER_RS485_ENABLED)
+			writeb(MCFUART_UCR_TXDISABLE,
+				port->membase + MCFUART_UCR);
 	}
 }
 
@@ -418,6 +436,58 @@ static int mcf_verify_port(struct uart_port *port, struct serial_struct *ser)
 
 /****************************************************************************/
 
+/* Enable or disable the RS485 support */
+static void mcf_config_rs485(struct uart_port *port, struct serial_rs485 *rs485)
+{
+	struct mcf_uart *pp = container_of(port, struct mcf_uart, port);
+	unsigned long flags;
+	unsigned char mr1, mr2;
+
+	spin_lock_irqsave(&port->lock, flags);
+	/* Get mode registers */
+	mr1 = readb(port->membase + MCFUART_UMR);
+	mr2 = readb(port->membase + MCFUART_UMR);
+	if (rs485->flags & SER_RS485_ENABLED) {
+		dev_dbg(port->dev, "Setting UART to RS485\n");
+		/* Automatically negate RTS after TX completes */
+		mr2 |= MCFUART_MR2_TXRTS;
+	} else {
+		dev_dbg(port->dev, "Setting UART to RS232\n");
+		mr2 &= ~MCFUART_MR2_TXRTS;
+	}
+	writeb(mr1, port->membase + MCFUART_UMR);
+	writeb(mr2, port->membase + MCFUART_UMR);
+	pp->rs485 = *rs485;
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static int mcf_ioctl(struct uart_port *port, unsigned int cmd,
+		unsigned long arg)
+{
+	switch (cmd) {
+	case TIOCSRS485: {
+		struct serial_rs485 rs485;
+		if (copy_from_user(&rs485, (struct serial_rs485 *)arg,
+				sizeof(struct serial_rs485)))
+			return -EFAULT;
+		mcf_config_rs485(port, &rs485);
+		break;
+	}
+	case TIOCGRS485: {
+		struct mcf_uart *pp = container_of(port, struct mcf_uart, port);
+		if (copy_to_user((struct serial_rs485 *)arg, &pp->rs485,
+				sizeof(struct serial_rs485)))
+			return -EFAULT;
+		break;
+	}
+	default:
+		return -ENOIOCTLCMD;
+	}
+	return 0;
+}
+
+/****************************************************************************/
+
 /*
  *	Define the basic serial functions we support.
  */
@@ -438,6 +508,7 @@ static const struct uart_ops mcf_uart_ops = {
 	.release_port	= mcf_release_port,
 	.config_port	= mcf_config_port,
 	.verify_port	= mcf_verify_port,
+	.ioctl		= mcf_ioctl,
 };
 
 static struct mcf_uart mcf_ports[4];
diff --git a/drivers/tty/serial/mfd.c b/drivers/tty/serial/mfd.c
index 2c01344dc33..5f4765a7a5c 100644
--- a/drivers/tty/serial/mfd.c
+++ b/drivers/tty/serial/mfd.c
@@ -387,12 +387,9 @@ void hsu_dma_rx(struct uart_hsu_port *up, u32 int_sts)
 	struct hsu_dma_buffer *dbuf = &up->rxbuf;
 	struct hsu_dma_chan *chan = up->rxc;
 	struct uart_port *port = &up->port;
-	struct tty_struct *tty = port->state->port.tty;
+	struct tty_port *tport = &port->state->port;
 	int count;
 
-	if (!tty)
-		return;
-
 	/*
 	 * First need to know how many is already transferred,
 	 * then check if its a timeout DMA irq, and return
@@ -423,7 +420,7 @@ void hsu_dma_rx(struct uart_hsu_port *up, u32 int_sts)
 	 * explicitly set tail to 0. So head will
 	 * always be greater than tail.
 	 */
-	tty_insert_flip_string(tty, dbuf->buf, count);
+	tty_insert_flip_string(tport, dbuf->buf, count);
 	port->icount.rx += count;
 
 	dma_sync_single_for_device(up->port.dev, dbuf->dma_addr,
@@ -437,7 +434,7 @@ void hsu_dma_rx(struct uart_hsu_port *up, u32 int_sts)
 					 | (0x1 << 16)
 					 | (0x1 << 24)	/* timeout bit, see HSU Errata 1 */
 					 );
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(tport);
 
 	chan_writel(chan, HSU_CH_CR, 0x3);
 
@@ -460,13 +457,9 @@ static void serial_hsu_stop_rx(struct uart_port *port)
 
 static inline void receive_chars(struct uart_hsu_port *up, int *status)
 {
-	struct tty_struct *tty = up->port.state->port.tty;
 	unsigned int ch, flag;
 	unsigned int max_count = 256;
 
-	if (!tty)
-		return;
-
 	do {
 		ch = serial_in(up, UART_RX);
 		flag = TTY_NORMAL;
@@ -522,7 +515,7 @@ static inline void receive_chars(struct uart_hsu_port *up, int *status)
 	ignore_char:
 		*status = serial_in(up, UART_LSR);
 	} while ((*status & UART_LSR_DR) && max_count--);
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&up->port.state->port);
 }
 
 static void transmit_chars(struct uart_hsu_port *up)
diff --git a/drivers/tty/serial/mpc52xx_uart.c b/drivers/tty/serial/mpc52xx_uart.c
index 7c23c4f4c58..c0e1fad51be 100644
--- a/drivers/tty/serial/mpc52xx_uart.c
+++ b/drivers/tty/serial/mpc52xx_uart.c
@@ -941,7 +941,7 @@ static struct uart_ops mpc52xx_uart_ops = {
 static inline int
 mpc52xx_uart_int_rx_chars(struct uart_port *port)
 {
-	struct tty_struct *tty = port->state->port.tty;
+	struct tty_port *tport = &port->state->port;
 	unsigned char ch, flag;
 	unsigned short status;
 
@@ -986,20 +986,20 @@ mpc52xx_uart_int_rx_chars(struct uart_port *port)
 			out_8(&PSC(port)->command, MPC52xx_PSC_RST_ERR_STAT);
 
 		}
-		tty_insert_flip_char(tty, ch, flag);
+		tty_insert_flip_char(tport, ch, flag);
 		if (status & MPC52xx_PSC_SR_OE) {
 			/*
 			 * Overrun is special, since it's
 			 * reported immediately, and doesn't
 			 * affect the current character
 			 */
-			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+			tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 			port->icount.overrun++;
 		}
 	}
 
 	spin_unlock(&port->lock);
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(tport);
 	spin_lock(&port->lock);
 
 	return psc_ops->raw_rx_rdy(port);
diff --git a/drivers/tty/serial/mpsc.c b/drivers/tty/serial/mpsc.c
index 6a9c6605666..bc24f493167 100644
--- a/drivers/tty/serial/mpsc.c
+++ b/drivers/tty/serial/mpsc.c
@@ -937,7 +937,7 @@ static int serial_polled;
 static int mpsc_rx_intr(struct mpsc_port_info *pi)
 {
 	struct mpsc_rx_desc *rxre;
-	struct tty_struct *tty = pi->port.state->port.tty;
+	struct tty_port *port = &pi->port.state->port;
 	u32	cmdstat, bytes_in, i;
 	int	rc = 0;
 	u8	*bp;
@@ -968,10 +968,9 @@ static int mpsc_rx_intr(struct mpsc_port_info *pi)
 		}
 #endif
 		/* Following use of tty struct directly is deprecated */
-		if (unlikely(tty_buffer_request_room(tty, bytes_in)
-					< bytes_in)) {
-			if (tty->low_latency)
-				tty_flip_buffer_push(tty);
+		if (tty_buffer_request_room(port, bytes_in) < bytes_in) {
+			if (port->low_latency)
+				tty_flip_buffer_push(port);
 			/*
 			 * If this failed then we will throw away the bytes
 			 * but must do so to clear interrupts.
@@ -1040,10 +1039,10 @@ static int mpsc_rx_intr(struct mpsc_port_info *pi)
 						| SDMA_DESC_CMDSTAT_FR
 						| SDMA_DESC_CMDSTAT_OR)))
 				&& !(cmdstat & pi->port.ignore_status_mask)) {
-			tty_insert_flip_char(tty, *bp, flag);
+			tty_insert_flip_char(port, *bp, flag);
 		} else {
 			for (i=0; i<bytes_in; i++)
-				tty_insert_flip_char(tty, *bp++, TTY_NORMAL);
+				tty_insert_flip_char(port, *bp++, TTY_NORMAL);
 
 			pi->port.icount.rx += bytes_in;
 		}
@@ -1081,7 +1080,7 @@ next_frame:
 	if ((readl(pi->sdma_base + SDMA_SDCM) & SDMA_SDCM_ERD) == 0)
 		mpsc_start_rx(pi);
 
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(port);
 	return rc;
 }
 
diff --git a/drivers/tty/serial/mrst_max3110.c b/drivers/tty/serial/mrst_max3110.c
index 58734d7e746..f641c232bec 100644
--- a/drivers/tty/serial/mrst_max3110.c
+++ b/drivers/tty/serial/mrst_max3110.c
@@ -339,7 +339,7 @@ static int
 receive_chars(struct uart_max3110 *max, unsigned short *str, int len)
 {
 	struct uart_port *port = &max->port;
-	struct tty_struct *tty;
+	struct tty_port *tport;
 	char buf[M3110_RX_FIFO_DEPTH];
 	int r, w, usable;
 
@@ -347,9 +347,7 @@ receive_chars(struct uart_max3110 *max, unsigned short *str, int len)
 	if (!port->state)
 		return 0;
 
-	tty = tty_port_tty_get(&port->state->port);
-	if (!tty)
-		return 0;
+	tport = &port->state->port;
 
 	for (r = 0, w = 0; r < len; r++) {
 		if (str[r] & MAX3110_BREAK &&
@@ -364,20 +362,17 @@ receive_chars(struct uart_max3110 *max, unsigned short *str, int len)
 		}
 	}
 
-	if (!w) {
-		tty_kref_put(tty);
+	if (!w)
 		return 0;
-	}
 
 	for (r = 0; w; r += usable, w -= usable) {
-		usable = tty_buffer_request_room(tty, w);
+		usable = tty_buffer_request_room(tport, w);
 		if (usable) {
-			tty_insert_flip_string(tty, buf + r, usable);
+			tty_insert_flip_string(tport, buf + r, usable);
 			port->icount.rx += usable;
 		}
 	}
-	tty_flip_buffer_push(tty);
-	tty_kref_put(tty);
+	tty_flip_buffer_push(tport);
 
 	return r;
 }
@@ -493,7 +488,7 @@ static int serial_m3110_startup(struct uart_port *port)
 			| WC_BAUD_DR2;
 
 	/* as we use thread to handle tx/rx, need set low latency */
-	port->state->port.tty->low_latency = 1;
+	port->state->port.low_latency = 1;
 
 	if (max->irq) {
 		max->read_thread = NULL;
diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c
index 95fd39be293..b11e99797fd 100644
--- a/drivers/tty/serial/msm_serial.c
+++ b/drivers/tty/serial/msm_serial.c
@@ -91,14 +91,14 @@ static void msm_enable_ms(struct uart_port *port)
 
 static void handle_rx_dm(struct uart_port *port, unsigned int misr)
 {
-	struct tty_struct *tty = port->state->port.tty;
+	struct tty_port *tport = &port->state->port;
 	unsigned int sr;
 	int count = 0;
 	struct msm_port *msm_port = UART_TO_MSM(port);
 
 	if ((msm_read(port, UART_SR) & UART_SR_OVERRUN)) {
 		port->icount.overrun++;
-		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 		msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
 	}
 
@@ -132,12 +132,12 @@ static void handle_rx_dm(struct uart_port *port, unsigned int misr)
 			port->icount.frame++;
 
 		/* TODO: handle sysrq */
-		tty_insert_flip_string(tty, (char *) &c,
+		tty_insert_flip_string(tport, (char *)&c,
 				       (count > 4) ? 4 : count);
 		count -= 4;
 	}
 
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(tport);
 	if (misr & (UART_IMR_RXSTALE))
 		msm_write(port, UART_CR_CMD_RESET_STALE_INT, UART_CR);
 	msm_write(port, 0xFFFFFF, UARTDM_DMRX);
@@ -146,7 +146,7 @@ static void handle_rx_dm(struct uart_port *port, unsigned int misr)
 
 static void handle_rx(struct uart_port *port)
 {
-	struct tty_struct *tty = port->state->port.tty;
+	struct tty_port *tport = &port->state->port;
 	unsigned int sr;
 
 	/*
@@ -155,7 +155,7 @@ static void handle_rx(struct uart_port *port)
 	 */
 	if ((msm_read(port, UART_SR) & UART_SR_OVERRUN)) {
 		port->icount.overrun++;
-		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 		msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
 	}
 
@@ -186,10 +186,10 @@ static void handle_rx(struct uart_port *port)
 		}
 
 		if (!uart_handle_sysrq_char(port, c))
-			tty_insert_flip_char(tty, c, flag);
+			tty_insert_flip_char(tport, c, flag);
 	}
 
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(tport);
 }
 
 static void reset_dm_count(struct uart_port *port)
diff --git a/drivers/tty/serial/msm_serial_hs.c b/drivers/tty/serial/msm_serial_hs.c
index 1fa92284ade..4a942c78347 100644
--- a/drivers/tty/serial/msm_serial_hs.c
+++ b/drivers/tty/serial/msm_serial_hs.c
@@ -908,6 +908,7 @@ static void msm_hs_dmov_rx_callback(struct msm_dmov_cmd *cmd_ptr,
 	unsigned long flags;
 	unsigned int flush;
 	struct tty_struct *tty;
+	struct tty_port *port;
 	struct uart_port *uport;
 	struct msm_hs_port *msm_uport;
 
@@ -917,7 +918,8 @@ static void msm_hs_dmov_rx_callback(struct msm_dmov_cmd *cmd_ptr,
 	spin_lock_irqsave(&uport->lock, flags);
 	clk_enable(msm_uport->clk);
 
-	tty = uport->state->port.tty;
+	port = &uport->state->port;
+	tty = port->tty;
 
 	msm_hs_write(uport, UARTDM_CR_ADDR, STALE_EVENT_DISABLE);
 
@@ -926,7 +928,7 @@ static void msm_hs_dmov_rx_callback(struct msm_dmov_cmd *cmd_ptr,
 	/* overflow is not connect to data in a FIFO */
 	if (unlikely((status & UARTDM_SR_OVERRUN_BMSK) &&
 		     (uport->read_status_mask & CREAD))) {
-		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+		tty_insert_flip_char(port, 0, TTY_OVERRUN);
 		uport->icount.buf_overrun++;
 		error_f = 1;
 	}
@@ -939,7 +941,7 @@ static void msm_hs_dmov_rx_callback(struct msm_dmov_cmd *cmd_ptr,
 		uport->icount.parity++;
 		error_f = 1;
 		if (uport->ignore_status_mask & IGNPAR)
-			tty_insert_flip_char(tty, 0, TTY_PARITY);
+			tty_insert_flip_char(port, 0, TTY_PARITY);
 	}
 
 	if (error_f)
@@ -959,7 +961,7 @@ static void msm_hs_dmov_rx_callback(struct msm_dmov_cmd *cmd_ptr,
 	rx_count = msm_hs_read(uport, UARTDM_RX_TOTAL_SNAP_ADDR);
 
 	if (0 != (uport->read_status_mask & CREAD)) {
-		retval = tty_insert_flip_string(tty, msm_uport->rx.buffer,
+		retval = tty_insert_flip_string(port, msm_uport->rx.buffer,
 						rx_count);
 		BUG_ON(retval != rx_count);
 	}
@@ -979,9 +981,8 @@ static void msm_hs_tty_flip_buffer_work(struct work_struct *work)
 {
 	struct msm_hs_port *msm_uport =
 			container_of(work, struct msm_hs_port, rx.tty_work);
-	struct tty_struct *tty = msm_uport->uport.state->port.tty;
 
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&msm_uport->uport.state->port);
 }
 
 /*
@@ -1344,7 +1345,6 @@ static irqreturn_t msm_hs_rx_wakeup_isr(int irq, void *dev)
 	unsigned long flags;
 	struct msm_hs_port *msm_uport = dev;
 	struct uart_port *uport = &msm_uport->uport;
-	struct tty_struct *tty = NULL;
 
 	spin_lock_irqsave(&uport->lock, flags);
 	if (msm_uport->clk_state == MSM_HS_CLK_OFF) {
@@ -1361,8 +1361,7 @@ static irqreturn_t msm_hs_rx_wakeup_isr(int irq, void *dev)
 		 * optionally inject char into tty rx */
 		msm_hs_request_clock_on_locked(uport);
 		if (msm_uport->rx_wakeup.inject_rx) {
-			tty = uport->state->port.tty;
-			tty_insert_flip_char(tty,
+			tty_insert_flip_char(&uport->state->port,
 					     msm_uport->rx_wakeup.rx_to_inject,
 					     TTY_NORMAL);
 			queue_work(msm_hs_workqueue, &msm_uport->rx.tty_work);
@@ -1400,7 +1399,7 @@ static int msm_hs_startup(struct uart_port *uport)
 
 	/* do not let tty layer execute RX in global workqueue, use a
 	 * dedicated workqueue managed by this driver */
-	uport->state->port.tty->low_latency = 1;
+	uport->state->port.low_latency = 1;
 
 	/* turn on uart clk */
 	ret = msm_hs_init_clk_locked(uport);
diff --git a/drivers/tty/serial/msm_smd_tty.c b/drivers/tty/serial/msm_smd_tty.c
index 925d1fa153d..e722ff163d9 100644
--- a/drivers/tty/serial/msm_smd_tty.c
+++ b/drivers/tty/serial/msm_smd_tty.c
@@ -70,7 +70,7 @@ static void smd_tty_notify(void *priv, unsigned event)
 		if (avail == 0)
 			break;
 
-		avail = tty_prepare_flip_string(tty, &ptr, avail);
+		avail = tty_prepare_flip_string(&info->port, &ptr, avail);
 
 		if (smd_read(info->ch, ptr, avail) != avail) {
 			/* shouldn't be possible since we're in interrupt
@@ -80,7 +80,7 @@ static void smd_tty_notify(void *priv, unsigned event)
 			pr_err("OOPS - smd_tty_buffer mismatch?!");
 		}
 
-		tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(&info->port);
 	}
 
 	/* XXX only when writable and necessary */
diff --git a/drivers/tty/serial/mux.c b/drivers/tty/serial/mux.c
index e2775b6df5a..7fd6aaaacd8 100644
--- a/drivers/tty/serial/mux.c
+++ b/drivers/tty/serial/mux.c
@@ -242,8 +242,8 @@ static void mux_write(struct uart_port *port)
  */
 static void mux_read(struct uart_port *port)
 {
+	struct tty_port *tport = &port->state->port;
 	int data;
-	struct tty_struct *tty = port->state->port.tty;
 	__u32 start_count = port->icount.rx;
 
 	while(1) {
@@ -266,12 +266,11 @@ static void mux_read(struct uart_port *port)
 		if (uart_handle_sysrq_char(port, data & 0xffu))
 			continue;
 
-		tty_insert_flip_char(tty, data & 0xFF, TTY_NORMAL);
+		tty_insert_flip_char(tport, data & 0xFF, TTY_NORMAL);
 	}
 	
-	if (start_count != port->icount.rx) {
-		tty_flip_buffer_push(tty);
-	}
+	if (start_count != port->icount.rx)
+		tty_flip_buffer_push(tport);
 }
 
 /**
diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c
index e55615eb34a..d549fe1fa42 100644
--- a/drivers/tty/serial/mxs-auart.c
+++ b/drivers/tty/serial/mxs-auart.c
@@ -364,7 +364,6 @@ out:
 
 static void mxs_auart_rx_chars(struct mxs_auart_port *s)
 {
-	struct tty_struct *tty = s->port.state->port.tty;
 	u32 stat = 0;
 
 	for (;;) {
@@ -375,7 +374,7 @@ static void mxs_auart_rx_chars(struct mxs_auart_port *s)
 	}
 
 	writel(stat, s->port.membase + AUART_STAT);
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&s->port.state->port);
 }
 
 static int mxs_auart_request_port(struct uart_port *u)
@@ -459,7 +458,7 @@ static int mxs_auart_dma_prep_rx(struct mxs_auart_port *s);
 static void dma_rx_callback(void *arg)
 {
 	struct mxs_auart_port *s = (struct mxs_auart_port *) arg;
-	struct tty_struct *tty = s->port.state->port.tty;
+	struct tty_port *port = &s->port.state->port;
 	int count;
 	u32 stat;
 
@@ -470,10 +469,10 @@ static void dma_rx_callback(void *arg)
 			AUART_STAT_PERR | AUART_STAT_FERR);
 
 	count = stat & AUART_STAT_RXCOUNT_MASK;
-	tty_insert_flip_string(tty, s->rx_dma_buf, count);
+	tty_insert_flip_string(port, s->rx_dma_buf, count);
 
 	writel(stat, s->port.membase + AUART_STAT);
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(port);
 
 	/* start the next DMA for RX. */
 	mxs_auart_dma_prep_rx(s);
@@ -552,7 +551,7 @@ static int mxs_auart_dma_init(struct mxs_auart_port *s)
 		return 0;
 
 	/* We do not get the right DMA channels. */
-	if (s->dma_channel_rx == -1 || s->dma_channel_rx == -1)
+	if (s->dma_channel_rx == -1 || s->dma_channel_tx == -1)
 		return -EINVAL;
 
 	/* init for RX */
diff --git a/drivers/tty/serial/netx-serial.c b/drivers/tty/serial/netx-serial.c
index d40da78e7c8..b9a40ed70be 100644
--- a/drivers/tty/serial/netx-serial.c
+++ b/drivers/tty/serial/netx-serial.c
@@ -199,7 +199,6 @@ static void netx_txint(struct uart_port *port)
 static void netx_rxint(struct uart_port *port)
 {
 	unsigned char rx, flg, status;
-	struct tty_struct *tty = port->state->port.tty;
 
 	while (!(readl(port->membase + UART_FR) & FR_RXFE)) {
 		rx = readl(port->membase + UART_DR);
@@ -237,8 +236,7 @@ static void netx_rxint(struct uart_port *port)
 		uart_insert_char(port, status, SR_OE, rx, flg);
 	}
 
-	tty_flip_buffer_push(tty);
-	return;
+	tty_flip_buffer_push(&port->state->port);
 }
 
 static irqreturn_t netx_int(int irq, void *dev_id)
diff --git a/drivers/tty/serial/nwpserial.c b/drivers/tty/serial/nwpserial.c
index dd4c31d1aee..77287c54f33 100644
--- a/drivers/tty/serial/nwpserial.c
+++ b/drivers/tty/serial/nwpserial.c
@@ -128,7 +128,7 @@ static void nwpserial_config_port(struct uart_port *port, int flags)
 static irqreturn_t nwpserial_interrupt(int irq, void *dev_id)
 {
 	struct nwpserial_port *up = dev_id;
-	struct tty_struct *tty = up->port.state->port.tty;
+	struct tty_port *port = &up->port.state->port;
 	irqreturn_t ret;
 	unsigned int iir;
 	unsigned char ch;
@@ -146,10 +146,10 @@ static irqreturn_t nwpserial_interrupt(int irq, void *dev_id)
 		up->port.icount.rx++;
 		ch = dcr_read(up->dcr_host, UART_RX);
 		if (up->port.ignore_status_mask != NWPSERIAL_STATUS_RXVALID)
-			tty_insert_flip_char(tty, ch, TTY_NORMAL);
+			tty_insert_flip_char(port, ch, TTY_NORMAL);
 	} while (dcr_read(up->dcr_host, UART_LSR) & UART_LSR_DR);
 
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(port);
 	ret = IRQ_HANDLED;
 
 	/* clear interrupt */
diff --git a/drivers/tty/serial/of_serial.c b/drivers/tty/serial/of_serial.c
index e7cae1c2d7d..d5874605682 100644
--- a/drivers/tty/serial/of_serial.c
+++ b/drivers/tty/serial/of_serial.c
@@ -18,7 +18,6 @@
 #include <linux/serial_reg.h>
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
-#include <linux/of_serial.h>
 #include <linux/of_platform.h>
 #include <linux/nwpserial.h>
 #include <linux/clk.h>
@@ -45,8 +44,10 @@ void tegra_serial_handle_break(struct uart_port *p)
 		udelay(1);
 	} while (1);
 }
-/* FIXME remove this export when tegra finishes conversion to open firmware */
-EXPORT_SYMBOL_GPL(tegra_serial_handle_break);
+#else
+static inline void tegra_serial_handle_break(struct uart_port *port)
+{
+}
 #endif
 
 /*
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 57d6b29c039..4dc41408ecb 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -59,6 +59,7 @@
 
 /* SCR register bitmasks */
 #define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK		(1 << 7)
+#define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK		(1 << 6)
 #define OMAP_UART_SCR_TX_EMPTY			(1 << 3)
 
 /* FCR register bitmasks */
@@ -232,24 +233,42 @@ static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
 }
 
 /*
+ * serial_omap_baud_is_mode16 - check if baud rate is MODE16X
+ * @port: uart port info
+ * @baud: baudrate for which mode needs to be determined
+ *
+ * Returns true if baud rate is MODE16X and false if MODE13X
+ * Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values,
+ * and Error Rates" determines modes not for all common baud rates.
+ * E.g. for 1000000 baud rate mode must be 16x, but according to that
+ * table it's determined as 13x.
+ */
+static bool
+serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
+{
+	unsigned int n13 = port->uartclk / (13 * baud);
+	unsigned int n16 = port->uartclk / (16 * baud);
+	int baudAbsDiff13 = baud - (port->uartclk / (13 * n13));
+	int baudAbsDiff16 = baud - (port->uartclk / (16 * n16));
+	if(baudAbsDiff13 < 0)
+		baudAbsDiff13 = -baudAbsDiff13;
+	if(baudAbsDiff16 < 0)
+		baudAbsDiff16 = -baudAbsDiff16;
+
+	return (baudAbsDiff13 > baudAbsDiff16);
+}
+
+/*
  * serial_omap_get_divisor - calculate divisor value
  * @port: uart port info
  * @baud: baudrate for which divisor needs to be calculated.
- *
- * We have written our own function to get the divisor so as to support
- * 13x mode. 3Mbps Baudrate as an different divisor.
- * Reference OMAP TRM Chapter 17:
- * Table 17-1. UART Mode Baud Rates, Divisor Values, and Error Rates
- * referring to oversampling - divisor value
- * baudrate 460,800 to 3,686,400 all have divisor 13
- * except 3,000,000 which has divisor value 16
  */
 static unsigned int
 serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
 {
 	unsigned int divisor;
 
-	if (baud > OMAP_MODE13X_SPEED && baud != 3000000)
+	if (!serial_omap_baud_is_mode16(port, baud))
 		divisor = 13;
 	else
 		divisor = 16;
@@ -302,9 +321,6 @@ static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
 	struct circ_buf *xmit = &up->port.state->xmit;
 	int count;
 
-	if (!(lsr & UART_LSR_THRE))
-		return;
-
 	if (up->port.x_char) {
 		serial_out(up, UART_TX, up->port.x_char);
 		up->port.icount.tx++;
@@ -483,7 +499,6 @@ static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr)
 static irqreturn_t serial_omap_irq(int irq, void *dev_id)
 {
 	struct uart_omap_port *up = dev_id;
-	struct tty_struct *tty = up->port.state->port.tty;
 	unsigned int iir, lsr;
 	unsigned int type;
 	irqreturn_t ret = IRQ_NONE;
@@ -530,7 +545,7 @@ static irqreturn_t serial_omap_irq(int irq, void *dev_id)
 
 	spin_unlock(&up->port.lock);
 
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&up->port.state->port);
 
 	pm_runtime_mark_last_busy(up->dev);
 	pm_runtime_put_autosuspend(up->dev);
@@ -776,6 +791,8 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
 		cval |= UART_LCR_PARITY;
 	if (!(termios->c_cflag & PARODD))
 		cval |= UART_LCR_EPAR;
+	if (termios->c_cflag & CMSPAR)
+		cval |= UART_LCR_SPAR;
 
 	/*
 	 * Ask the core to calculate the divisor for us.
@@ -845,7 +862,7 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
 	serial_out(up, UART_IER, up->ier);
 	serial_out(up, UART_LCR, cval);		/* reset DLAB */
 	up->lcr = cval;
-	up->scr = OMAP_UART_SCR_TX_EMPTY;
+	up->scr = 0;
 
 	/* FIFOs and DMA Settings */
 
@@ -869,8 +886,6 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
 	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
 	/* FIFO ENABLE, DMA MODE */
 
-	up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
-
 	/* Set receive FIFO threshold to 16 characters and
 	 * transmit FIFO threshold to 16 spaces
 	 */
@@ -915,7 +930,7 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
 	serial_out(up, UART_EFR, up->efr);
 	serial_out(up, UART_LCR, cval);
 
-	if (baud > 230400 && baud != 3000000)
+	if (!serial_omap_baud_is_mode16(port, baud))
 		up->mdr1 = UART_OMAP_MDR1_13X_MODE;
 	else
 		up->mdr1 = UART_OMAP_MDR1_16X_MODE;
diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index 8318925fbf6..7a6c989924b 100644
--- a/drivers/tty/serial/pch_uart.c
+++ b/drivers/tty/serial/pch_uart.c
@@ -14,18 +14,21 @@
  *along with this program; if not, write to the Free Software
  *Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  */
+#if defined(CONFIG_SERIAL_PCH_UART_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
 #include <linux/kernel.h>
 #include <linux/serial_reg.h>
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/pci.h>
+#include <linux/console.h>
 #include <linux/serial_core.h>
 #include <linux/tty.h>
 #include <linux/tty_flip.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/dmi.h>
-#include <linux/console.h>
 #include <linux/nmi.h>
 #include <linux/delay.h>
 
@@ -553,12 +556,26 @@ static int pch_uart_hal_read(struct eg20t_port *priv, unsigned char *buf,
 {
 	int i;
 	u8 rbr, lsr;
+	struct uart_port *port = &priv->port;
 
 	lsr = ioread8(priv->membase + UART_LSR);
 	for (i = 0, lsr = ioread8(priv->membase + UART_LSR);
-	     i < rx_size && lsr & UART_LSR_DR;
+	     i < rx_size && lsr & (UART_LSR_DR | UART_LSR_BI);
 	     lsr = ioread8(priv->membase + UART_LSR)) {
 		rbr = ioread8(priv->membase + PCH_UART_RBR);
+
+		if (lsr & UART_LSR_BI) {
+			port->icount.brk++;
+			if (uart_handle_break(port))
+				continue;
+		}
+#ifdef SUPPORT_SYSRQ
+		if (port->sysrq) {
+			if (uart_handle_sysrq_char(port, rbr))
+				continue;
+		}
+#endif
+
 		buf[i++] = rbr;
 	}
 	return i;
@@ -591,19 +608,11 @@ static void pch_uart_hal_set_break(struct eg20t_port *priv, int on)
 static int push_rx(struct eg20t_port *priv, const unsigned char *buf,
 		   int size)
 {
-	struct uart_port *port;
-	struct tty_struct *tty;
-
-	port = &priv->port;
-	tty = tty_port_tty_get(&port->state->port);
-	if (!tty) {
-		dev_dbg(priv->port.dev, "%s:tty is busy now", __func__);
-		return -EBUSY;
-	}
+	struct uart_port *port = &priv->port;
+	struct tty_port *tport = &port->state->port;
 
-	tty_insert_flip_string(tty, buf, size);
-	tty_flip_buffer_push(tty);
-	tty_kref_put(tty);
+	tty_insert_flip_string(tport, buf, size);
+	tty_flip_buffer_push(tport);
 
 	return 0;
 }
@@ -629,15 +638,16 @@ static int dma_push_rx(struct eg20t_port *priv, int size)
 	struct tty_struct *tty;
 	int room;
 	struct uart_port *port = &priv->port;
+	struct tty_port *tport = &port->state->port;
 
 	port = &priv->port;
-	tty = tty_port_tty_get(&port->state->port);
+	tty = tty_port_tty_get(tport);
 	if (!tty) {
 		dev_dbg(priv->port.dev, "%s:tty is busy now", __func__);
 		return 0;
 	}
 
-	room = tty_buffer_request_room(tty, size);
+	room = tty_buffer_request_room(tport, size);
 
 	if (room < size)
 		dev_warn(port->dev, "Rx overrun: dropping %u bytes\n",
@@ -645,7 +655,7 @@ static int dma_push_rx(struct eg20t_port *priv, int size)
 	if (!room)
 		return room;
 
-	tty_insert_flip_string(tty, sg_virt(&priv->sg_rx), size);
+	tty_insert_flip_string(tport, sg_virt(&priv->sg_rx), size);
 
 	port->icount.rx += room;
 	tty_kref_put(tty);
@@ -743,19 +753,12 @@ static void pch_dma_rx_complete(void *arg)
 {
 	struct eg20t_port *priv = arg;
 	struct uart_port *port = &priv->port;
-	struct tty_struct *tty = tty_port_tty_get(&port->state->port);
 	int count;
 
-	if (!tty) {
-		dev_dbg(priv->port.dev, "%s:tty is busy now", __func__);
-		return;
-	}
-
 	dma_sync_sg_for_cpu(port->dev, &priv->sg_rx, 1, DMA_FROM_DEVICE);
 	count = dma_push_rx(priv, priv->trigger_level);
 	if (count)
-		tty_flip_buffer_push(tty);
-	tty_kref_put(tty);
+		tty_flip_buffer_push(&port->state->port);
 	async_tx_ack(priv->desc_rx);
 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_RX_INT |
 					    PCH_UART_HAL_RX_ERR_INT);
@@ -1037,23 +1040,33 @@ static unsigned int dma_handle_tx(struct eg20t_port *priv)
 
 static void pch_uart_err_ir(struct eg20t_port *priv, unsigned int lsr)
 {
-	u8 fcr = ioread8(priv->membase + UART_FCR);
-
-	/* Reset FIFO */
-	fcr |= UART_FCR_CLEAR_RCVR;
-	iowrite8(fcr, priv->membase + UART_FCR);
+	struct uart_port *port = &priv->port;
+	struct tty_struct *tty = tty_port_tty_get(&port->state->port);
+	char   *error_msg[5] = {};
+	int    i = 0;
 
 	if (lsr & PCH_UART_LSR_ERR)
-		dev_err(&priv->pdev->dev, "Error data in FIFO\n");
+		error_msg[i++] = "Error data in FIFO\n";
 
-	if (lsr & UART_LSR_FE)
-		dev_err(&priv->pdev->dev, "Framing Error\n");
+	if (lsr & UART_LSR_FE) {
+		port->icount.frame++;
+		error_msg[i++] = "  Framing Error\n";
+	}
 
-	if (lsr & UART_LSR_PE)
-		dev_err(&priv->pdev->dev, "Parity Error\n");
+	if (lsr & UART_LSR_PE) {
+		port->icount.parity++;
+		error_msg[i++] = "  Parity Error\n";
+	}
 
-	if (lsr & UART_LSR_OE)
-		dev_err(&priv->pdev->dev, "Overrun Error\n");
+	if (lsr & UART_LSR_OE) {
+		port->icount.overrun++;
+		error_msg[i++] = "  Overrun Error\n";
+	}
+
+	if (tty == NULL) {
+		for (i = 0; error_msg[i] != NULL; i++)
+			dev_err(&priv->pdev->dev, error_msg[i]);
+	}
 }
 
 static irqreturn_t pch_uart_interrupt(int irq, void *dev_id)
@@ -1564,7 +1577,8 @@ pch_console_write(struct console *co, const char *s, unsigned int count)
 
 	local_irq_save(flags);
 	if (priv->port.sysrq) {
-		spin_lock(&priv->lock);
+		/* call to uart_handle_sysrq_char already took the priv lock */
+		priv_locked = 0;
 		/* serial8250_handle_port() already took the port lock */
 		port_locked = 0;
 	} else if (oops_in_progress) {
diff --git a/drivers/tty/serial/pmac_zilog.c b/drivers/tty/serial/pmac_zilog.c
index 333c8d012b0..b1785f58b6e 100644
--- a/drivers/tty/serial/pmac_zilog.c
+++ b/drivers/tty/serial/pmac_zilog.c
@@ -227,19 +227,19 @@ static void pmz_interrupt_control(struct uart_pmac_port *uap, int enable)
 	write_zsreg(uap, R1, uap->curregs[1]);
 }
 
-static struct tty_struct *pmz_receive_chars(struct uart_pmac_port *uap)
+static bool pmz_receive_chars(struct uart_pmac_port *uap)
 {
-	struct tty_struct *tty = NULL;
+	struct tty_port *port;
 	unsigned char ch, r1, drop, error, flag;
 	int loops = 0;
 
 	/* Sanity check, make sure the old bug is no longer happening */
-	if (uap->port.state == NULL || uap->port.state->port.tty == NULL) {
+	if (uap->port.state == NULL) {
 		WARN_ON(1);
 		(void)read_zsdata(uap);
-		return NULL;
+		return false;
 	}
-	tty = uap->port.state->port.tty;
+	port = &uap->port.state->port;
 
 	while (1) {
 		error = 0;
@@ -309,10 +309,10 @@ static struct tty_struct *pmz_receive_chars(struct uart_pmac_port *uap)
 
 		if (uap->port.ignore_status_mask == 0xff ||
 		    (r1 & uap->port.ignore_status_mask) == 0) {
-			tty_insert_flip_char(tty, ch, flag);
+			tty_insert_flip_char(port, ch, flag);
 		}
 		if (r1 & Rx_OVR)
-			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+			tty_insert_flip_char(port, 0, TTY_OVERRUN);
 	next_char:
 		/* We can get stuck in an infinite loop getting char 0 when the
 		 * line is in a wrong HW state, we break that here.
@@ -328,11 +328,11 @@ static struct tty_struct *pmz_receive_chars(struct uart_pmac_port *uap)
 			break;
 	}
 
-	return tty;
+	return true;
  flood:
 	pmz_interrupt_control(uap, 0);
 	pmz_error("pmz: rx irq flood !\n");
-	return tty;
+	return true;
 }
 
 static void pmz_status_handle(struct uart_pmac_port *uap)
@@ -453,7 +453,7 @@ static irqreturn_t pmz_interrupt(int irq, void *dev_id)
 	struct uart_pmac_port *uap_a;
 	struct uart_pmac_port *uap_b;
 	int rc = IRQ_NONE;
-	struct tty_struct *tty;
+	bool push;
 	u8 r3;
 
 	uap_a = pmz_get_port_A(uap);
@@ -466,7 +466,7 @@ static irqreturn_t pmz_interrupt(int irq, void *dev_id)
 	pmz_debug("irq, r3: %x\n", r3);
 #endif
 	/* Channel A */
-	tty = NULL;
+	push = false;
 	if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
 		if (!ZS_IS_OPEN(uap_a)) {
 			pmz_debug("ChanA interrupt while not open !\n");
@@ -477,21 +477,21 @@ static irqreturn_t pmz_interrupt(int irq, void *dev_id)
 		if (r3 & CHAEXT)
 			pmz_status_handle(uap_a);
 		if (r3 & CHARxIP)
-			tty = pmz_receive_chars(uap_a);
+			push = pmz_receive_chars(uap_a);
 		if (r3 & CHATxIP)
 			pmz_transmit_chars(uap_a);
 		rc = IRQ_HANDLED;
 	}
  skip_a:
 	spin_unlock(&uap_a->port.lock);
-	if (tty != NULL)
-		tty_flip_buffer_push(tty);
+	if (push)
+		tty_flip_buffer_push(&uap->port.state->port);
 
 	if (!uap_b)
 		goto out;
 
 	spin_lock(&uap_b->port.lock);
-	tty = NULL;
+	push = false;
 	if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
 		if (!ZS_IS_OPEN(uap_b)) {
 			pmz_debug("ChanB interrupt while not open !\n");
@@ -502,15 +502,15 @@ static irqreturn_t pmz_interrupt(int irq, void *dev_id)
 		if (r3 & CHBEXT)
 			pmz_status_handle(uap_b);
 		if (r3 & CHBRxIP)
-			tty = pmz_receive_chars(uap_b);
+			push = pmz_receive_chars(uap_b);
 		if (r3 & CHBTxIP)
 			pmz_transmit_chars(uap_b);
 		rc = IRQ_HANDLED;
 	}
  skip_b:
 	spin_unlock(&uap_b->port.lock);
-	if (tty != NULL)
-		tty_flip_buffer_push(tty);
+	if (push)
+		tty_flip_buffer_push(&uap->port.state->port);
 
  out:
 	return rc;
diff --git a/drivers/tty/serial/pnx8xxx_uart.c b/drivers/tty/serial/pnx8xxx_uart.c
index 0aa75a97531..7e277a5384a 100644
--- a/drivers/tty/serial/pnx8xxx_uart.c
+++ b/drivers/tty/serial/pnx8xxx_uart.c
@@ -181,7 +181,6 @@ static void pnx8xxx_enable_ms(struct uart_port *port)
 
 static void pnx8xxx_rx_chars(struct pnx8xxx_port *sport)
 {
-	struct tty_struct *tty = sport->port.state->port.tty;
 	unsigned int status, ch, flg;
 
 	status = FIFO_TO_SM(serial_in(sport, PNX8XXX_FIFO)) |
@@ -238,7 +237,7 @@ static void pnx8xxx_rx_chars(struct pnx8xxx_port *sport)
 		status = FIFO_TO_SM(serial_in(sport, PNX8XXX_FIFO)) |
 			 ISTAT_TO_SM(serial_in(sport, PNX8XXX_ISTAT));
 	}
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&sport->port.state->port);
 }
 
 static void pnx8xxx_tx_chars(struct pnx8xxx_port *sport)
diff --git a/drivers/tty/serial/pxa.c b/drivers/tty/serial/pxa.c
index 2764828251f..05f504e0c27 100644
--- a/drivers/tty/serial/pxa.c
+++ b/drivers/tty/serial/pxa.c
@@ -98,7 +98,6 @@ static void serial_pxa_stop_rx(struct uart_port *port)
 
 static inline void receive_chars(struct uart_pxa_port *up, int *status)
 {
-	struct tty_struct *tty = up->port.state->port.tty;
 	unsigned int ch, flag;
 	int max_count = 256;
 
@@ -168,7 +167,7 @@ static inline void receive_chars(struct uart_pxa_port *up, int *status)
 	ignore_char:
 		*status = serial_in(up, UART_LSR);
 	} while ((*status & UART_LSR_DR) && (max_count-- > 0));
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&up->port.state->port);
 
 	/* work around Errata #20 according to
 	 * Intel(R) PXA27x Processor Family
@@ -673,8 +672,7 @@ serial_pxa_console_write(struct console *co, const char *s, unsigned int count)
 	unsigned long flags;
 	int locked = 1;
 
-	clk_prepare_enable(up->clk);
-
+	clk_enable(up->clk);
 	local_irq_save(flags);
 	if (up->port.sysrq)
 		locked = 0;
@@ -701,8 +699,8 @@ serial_pxa_console_write(struct console *co, const char *s, unsigned int count)
 	if (locked)
 		spin_unlock(&up->port.lock);
 	local_irq_restore(flags);
+	clk_disable(up->clk);
 
-	clk_disable_unprepare(up->clk);
 }
 
 #ifdef CONFIG_CONSOLE_POLL
@@ -899,6 +897,12 @@ static int serial_pxa_probe(struct platform_device *dev)
 		goto err_free;
 	}
 
+	ret = clk_prepare(sport->clk);
+	if (ret) {
+		clk_put(sport->clk);
+		goto err_free;
+	}
+
 	sport->port.type = PORT_PXA;
 	sport->port.iotype = UPIO_MEM;
 	sport->port.mapbase = mmres->start;
@@ -930,6 +934,7 @@ static int serial_pxa_probe(struct platform_device *dev)
 	return 0;
 
  err_clk:
+	clk_unprepare(sport->clk);
 	clk_put(sport->clk);
  err_free:
 	kfree(sport);
@@ -943,6 +948,8 @@ static int serial_pxa_remove(struct platform_device *dev)
 	platform_set_drvdata(dev, NULL);
 
 	uart_remove_one_port(&serial_pxa_reg, &sport->port);
+
+	clk_unprepare(sport->clk);
 	clk_put(sport->clk);
 	kfree(sport);
 
diff --git a/drivers/tty/serial/rp2.c b/drivers/tty/serial/rp2.c
new file mode 100644
index 00000000000..a314a943f12
--- /dev/null
+++ b/drivers/tty/serial/rp2.c
@@ -0,0 +1,885 @@
+/*
+ * Driver for Comtrol RocketPort EXPRESS/INFINITY cards
+ *
+ * Copyright (C) 2012 Kevin Cernekee <cernekee@gmail.com>
+ *
+ * Inspired by, and loosely based on:
+ *
+ *   ar933x_uart.c
+ *     Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
+ *
+ *   rocketport_infinity_express-linux-1.20.tar.gz
+ *     Copyright (C) 2004-2011 Comtrol, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#include <linux/bitops.h>
+#include <linux/compiler.h>
+#include <linux/completion.h>
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/log2.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/serial.h>
+#include <linux/serial_core.h>
+#include <linux/slab.h>
+#include <linux/sysrq.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/types.h>
+
+#define DRV_NAME			"rp2"
+
+#define RP2_FW_NAME			"rp2.fw"
+#define RP2_UCODE_BYTES			0x3f
+
+#define PORTS_PER_ASIC			16
+#define ALL_PORTS_MASK			(BIT(PORTS_PER_ASIC) - 1)
+
+#define UART_CLOCK			44236800
+#define DEFAULT_BAUD_DIV		(UART_CLOCK / (9600 * 16))
+#define FIFO_SIZE			512
+
+/* BAR0 registers */
+#define RP2_FPGA_CTL0			0x110
+#define RP2_FPGA_CTL1			0x11c
+#define RP2_IRQ_MASK			0x1ec
+#define RP2_IRQ_MASK_EN_m		BIT(0)
+#define RP2_IRQ_STATUS			0x1f0
+
+/* BAR1 registers */
+#define RP2_ASIC_SPACING		0x1000
+#define RP2_ASIC_OFFSET(i)		((i) << ilog2(RP2_ASIC_SPACING))
+
+#define RP2_PORT_BASE			0x000
+#define RP2_PORT_SPACING		0x040
+
+#define RP2_UCODE_BASE			0x400
+#define RP2_UCODE_SPACING		0x80
+
+#define RP2_CLK_PRESCALER		0xc00
+#define RP2_CH_IRQ_STAT			0xc04
+#define RP2_CH_IRQ_MASK			0xc08
+#define RP2_ASIC_IRQ			0xd00
+#define RP2_ASIC_IRQ_EN_m		BIT(20)
+#define RP2_GLOBAL_CMD			0xd0c
+#define RP2_ASIC_CFG			0xd04
+
+/* port registers */
+#define RP2_DATA_DWORD			0x000
+
+#define RP2_DATA_BYTE			0x008
+#define RP2_DATA_BYTE_ERR_PARITY_m	BIT(8)
+#define RP2_DATA_BYTE_ERR_OVERRUN_m	BIT(9)
+#define RP2_DATA_BYTE_ERR_FRAMING_m	BIT(10)
+#define RP2_DATA_BYTE_BREAK_m		BIT(11)
+
+/* This lets uart_insert_char() drop bytes received on a !CREAD port */
+#define RP2_DUMMY_READ			BIT(16)
+
+#define RP2_DATA_BYTE_EXCEPTION_MASK	(RP2_DATA_BYTE_ERR_PARITY_m | \
+					 RP2_DATA_BYTE_ERR_OVERRUN_m | \
+					 RP2_DATA_BYTE_ERR_FRAMING_m | \
+					 RP2_DATA_BYTE_BREAK_m)
+
+#define RP2_RX_FIFO_COUNT		0x00c
+#define RP2_TX_FIFO_COUNT		0x00e
+
+#define RP2_CHAN_STAT			0x010
+#define RP2_CHAN_STAT_RXDATA_m		BIT(0)
+#define RP2_CHAN_STAT_DCD_m		BIT(3)
+#define RP2_CHAN_STAT_DSR_m		BIT(4)
+#define RP2_CHAN_STAT_CTS_m		BIT(5)
+#define RP2_CHAN_STAT_RI_m		BIT(6)
+#define RP2_CHAN_STAT_OVERRUN_m		BIT(13)
+#define RP2_CHAN_STAT_DSR_CHANGED_m	BIT(16)
+#define RP2_CHAN_STAT_CTS_CHANGED_m	BIT(17)
+#define RP2_CHAN_STAT_CD_CHANGED_m	BIT(18)
+#define RP2_CHAN_STAT_RI_CHANGED_m	BIT(22)
+#define RP2_CHAN_STAT_TXEMPTY_m		BIT(25)
+
+#define RP2_CHAN_STAT_MS_CHANGED_MASK	(RP2_CHAN_STAT_DSR_CHANGED_m | \
+					 RP2_CHAN_STAT_CTS_CHANGED_m | \
+					 RP2_CHAN_STAT_CD_CHANGED_m | \
+					 RP2_CHAN_STAT_RI_CHANGED_m)
+
+#define RP2_TXRX_CTL			0x014
+#define RP2_TXRX_CTL_MSRIRQ_m		BIT(0)
+#define RP2_TXRX_CTL_RXIRQ_m		BIT(2)
+#define RP2_TXRX_CTL_RX_TRIG_s		3
+#define RP2_TXRX_CTL_RX_TRIG_m		(0x3 << RP2_TXRX_CTL_RX_TRIG_s)
+#define RP2_TXRX_CTL_RX_TRIG_1		(0x1 << RP2_TXRX_CTL_RX_TRIG_s)
+#define RP2_TXRX_CTL_RX_TRIG_256	(0x2 << RP2_TXRX_CTL_RX_TRIG_s)
+#define RP2_TXRX_CTL_RX_TRIG_448	(0x3 << RP2_TXRX_CTL_RX_TRIG_s)
+#define RP2_TXRX_CTL_RX_EN_m		BIT(5)
+#define RP2_TXRX_CTL_RTSFLOW_m		BIT(6)
+#define RP2_TXRX_CTL_DTRFLOW_m		BIT(7)
+#define RP2_TXRX_CTL_TX_TRIG_s		16
+#define RP2_TXRX_CTL_TX_TRIG_m		(0x3 << RP2_TXRX_CTL_RX_TRIG_s)
+#define RP2_TXRX_CTL_DSRFLOW_m		BIT(18)
+#define RP2_TXRX_CTL_TXIRQ_m		BIT(19)
+#define RP2_TXRX_CTL_CTSFLOW_m		BIT(23)
+#define RP2_TXRX_CTL_TX_EN_m		BIT(24)
+#define RP2_TXRX_CTL_RTS_m		BIT(25)
+#define RP2_TXRX_CTL_DTR_m		BIT(26)
+#define RP2_TXRX_CTL_LOOP_m		BIT(27)
+#define RP2_TXRX_CTL_BREAK_m		BIT(28)
+#define RP2_TXRX_CTL_CMSPAR_m		BIT(29)
+#define RP2_TXRX_CTL_nPARODD_m		BIT(30)
+#define RP2_TXRX_CTL_PARENB_m		BIT(31)
+
+#define RP2_UART_CTL			0x018
+#define RP2_UART_CTL_MODE_s		0
+#define RP2_UART_CTL_MODE_m		(0x7 << RP2_UART_CTL_MODE_s)
+#define RP2_UART_CTL_MODE_rs232		(0x1 << RP2_UART_CTL_MODE_s)
+#define RP2_UART_CTL_FLUSH_RX_m		BIT(3)
+#define RP2_UART_CTL_FLUSH_TX_m		BIT(4)
+#define RP2_UART_CTL_RESET_CH_m		BIT(5)
+#define RP2_UART_CTL_XMIT_EN_m		BIT(6)
+#define RP2_UART_CTL_DATABITS_s		8
+#define RP2_UART_CTL_DATABITS_m		(0x3 << RP2_UART_CTL_DATABITS_s)
+#define RP2_UART_CTL_DATABITS_8		(0x3 << RP2_UART_CTL_DATABITS_s)
+#define RP2_UART_CTL_DATABITS_7		(0x2 << RP2_UART_CTL_DATABITS_s)
+#define RP2_UART_CTL_DATABITS_6		(0x1 << RP2_UART_CTL_DATABITS_s)
+#define RP2_UART_CTL_DATABITS_5		(0x0 << RP2_UART_CTL_DATABITS_s)
+#define RP2_UART_CTL_STOPBITS_m		BIT(10)
+
+#define RP2_BAUD			0x01c
+
+/* ucode registers */
+#define RP2_TX_SWFLOW			0x02
+#define RP2_TX_SWFLOW_ena		0x81
+#define RP2_TX_SWFLOW_dis		0x9d
+
+#define RP2_RX_SWFLOW			0x0c
+#define RP2_RX_SWFLOW_ena		0x81
+#define RP2_RX_SWFLOW_dis		0x8d
+
+#define RP2_RX_FIFO			0x37
+#define RP2_RX_FIFO_ena			0x08
+#define RP2_RX_FIFO_dis			0x81
+
+static struct uart_driver rp2_uart_driver = {
+	.owner				= THIS_MODULE,
+	.driver_name			= DRV_NAME,
+	.dev_name			= "ttyRP",
+	.nr				= CONFIG_SERIAL_RP2_NR_UARTS,
+};
+
+struct rp2_card;
+
+struct rp2_uart_port {
+	struct uart_port		port;
+	int				idx;
+	int				ignore_rx;
+	struct rp2_card			*card;
+	void __iomem			*asic_base;
+	void __iomem			*base;
+	void __iomem			*ucode;
+};
+
+struct rp2_card {
+	struct pci_dev			*pdev;
+	struct rp2_uart_port		*ports;
+	int				n_ports;
+	int				initialized_ports;
+	int				minor_start;
+	int				smpte;
+	void __iomem			*bar0;
+	void __iomem			*bar1;
+	spinlock_t			card_lock;
+	struct completion		fw_loaded;
+};
+
+#define RP_ID(prod) PCI_VDEVICE(RP, (prod))
+#define RP_CAP(ports, smpte) (((ports) << 8) | ((smpte) << 0))
+
+static inline void rp2_decode_cap(const struct pci_device_id *id,
+				  int *ports, int *smpte)
+{
+	*ports = id->driver_data >> 8;
+	*smpte = id->driver_data & 0xff;
+}
+
+static DEFINE_SPINLOCK(rp2_minor_lock);
+static int rp2_minor_next;
+
+static int rp2_alloc_ports(int n_ports)
+{
+	int ret = -ENOSPC;
+
+	spin_lock(&rp2_minor_lock);
+	if (rp2_minor_next + n_ports <= CONFIG_SERIAL_RP2_NR_UARTS) {
+		/* sorry, no support for hot unplugging individual cards */
+		ret = rp2_minor_next;
+		rp2_minor_next += n_ports;
+	}
+	spin_unlock(&rp2_minor_lock);
+
+	return ret;
+}
+
+static inline struct rp2_uart_port *port_to_up(struct uart_port *port)
+{
+	return container_of(port, struct rp2_uart_port, port);
+}
+
+static void rp2_rmw(struct rp2_uart_port *up, int reg,
+		    u32 clr_bits, u32 set_bits)
+{
+	u32 tmp = readl(up->base + reg);
+	tmp &= ~clr_bits;
+	tmp |= set_bits;
+	writel(tmp, up->base + reg);
+}
+
+static void rp2_rmw_clr(struct rp2_uart_port *up, int reg, u32 val)
+{
+	rp2_rmw(up, reg, val, 0);
+}
+
+static void rp2_rmw_set(struct rp2_uart_port *up, int reg, u32 val)
+{
+	rp2_rmw(up, reg, 0, val);
+}
+
+static void rp2_mask_ch_irq(struct rp2_uart_port *up, int ch_num,
+			    int is_enabled)
+{
+	unsigned long flags, irq_mask;
+
+	spin_lock_irqsave(&up->card->card_lock, flags);
+
+	irq_mask = readl(up->asic_base + RP2_CH_IRQ_MASK);
+	if (is_enabled)
+		irq_mask &= ~BIT(ch_num);
+	else
+		irq_mask |= BIT(ch_num);
+	writel(irq_mask, up->asic_base + RP2_CH_IRQ_MASK);
+
+	spin_unlock_irqrestore(&up->card->card_lock, flags);
+}
+
+static unsigned int rp2_uart_tx_empty(struct uart_port *port)
+{
+	struct rp2_uart_port *up = port_to_up(port);
+	unsigned long tx_fifo_bytes, flags;
+
+	/*
+	 * This should probably check the transmitter, not the FIFO.
+	 * But the TXEMPTY bit doesn't seem to work unless the TX IRQ is
+	 * enabled.
+	 */
+	spin_lock_irqsave(&up->port.lock, flags);
+	tx_fifo_bytes = readw(up->base + RP2_TX_FIFO_COUNT);
+	spin_unlock_irqrestore(&up->port.lock, flags);
+
+	return tx_fifo_bytes ? 0 : TIOCSER_TEMT;
+}
+
+static unsigned int rp2_uart_get_mctrl(struct uart_port *port)
+{
+	struct rp2_uart_port *up = port_to_up(port);
+	u32 status;
+
+	status = readl(up->base + RP2_CHAN_STAT);
+	return ((status & RP2_CHAN_STAT_DCD_m) ? TIOCM_CAR : 0) |
+	       ((status & RP2_CHAN_STAT_DSR_m) ? TIOCM_DSR : 0) |
+	       ((status & RP2_CHAN_STAT_CTS_m) ? TIOCM_CTS : 0) |
+	       ((status & RP2_CHAN_STAT_RI_m) ? TIOCM_RI : 0);
+}
+
+static void rp2_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+	rp2_rmw(port_to_up(port), RP2_TXRX_CTL,
+		RP2_TXRX_CTL_DTR_m | RP2_TXRX_CTL_RTS_m | RP2_TXRX_CTL_LOOP_m,
+		((mctrl & TIOCM_DTR) ? RP2_TXRX_CTL_DTR_m : 0) |
+		((mctrl & TIOCM_RTS) ? RP2_TXRX_CTL_RTS_m : 0) |
+		((mctrl & TIOCM_LOOP) ? RP2_TXRX_CTL_LOOP_m : 0));
+}
+
+static void rp2_uart_start_tx(struct uart_port *port)
+{
+	rp2_rmw_set(port_to_up(port), RP2_TXRX_CTL, RP2_TXRX_CTL_TXIRQ_m);
+}
+
+static void rp2_uart_stop_tx(struct uart_port *port)
+{
+	rp2_rmw_clr(port_to_up(port), RP2_TXRX_CTL, RP2_TXRX_CTL_TXIRQ_m);
+}
+
+static void rp2_uart_stop_rx(struct uart_port *port)
+{
+	rp2_rmw_clr(port_to_up(port), RP2_TXRX_CTL, RP2_TXRX_CTL_RXIRQ_m);
+}
+
+static void rp2_uart_break_ctl(struct uart_port *port, int break_state)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&port->lock, flags);
+	rp2_rmw(port_to_up(port), RP2_TXRX_CTL, RP2_TXRX_CTL_BREAK_m,
+		break_state ? RP2_TXRX_CTL_BREAK_m : 0);
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void rp2_uart_enable_ms(struct uart_port *port)
+{
+	rp2_rmw_set(port_to_up(port), RP2_TXRX_CTL, RP2_TXRX_CTL_MSRIRQ_m);
+}
+
+static void __rp2_uart_set_termios(struct rp2_uart_port *up,
+				   unsigned long cfl,
+				   unsigned long ifl,
+				   unsigned int baud_div)
+{
+	/* baud rate divisor (calculated elsewhere).  0 = divide-by-1 */
+	writew(baud_div - 1, up->base + RP2_BAUD);
+
+	/* data bits and stop bits */
+	rp2_rmw(up, RP2_UART_CTL,
+		RP2_UART_CTL_STOPBITS_m | RP2_UART_CTL_DATABITS_m,
+		((cfl & CSTOPB) ? RP2_UART_CTL_STOPBITS_m : 0) |
+		(((cfl & CSIZE) == CS8) ? RP2_UART_CTL_DATABITS_8 : 0) |
+		(((cfl & CSIZE) == CS7) ? RP2_UART_CTL_DATABITS_7 : 0) |
+		(((cfl & CSIZE) == CS6) ? RP2_UART_CTL_DATABITS_6 : 0) |
+		(((cfl & CSIZE) == CS5) ? RP2_UART_CTL_DATABITS_5 : 0));
+
+	/* parity and hardware flow control */
+	rp2_rmw(up, RP2_TXRX_CTL,
+		RP2_TXRX_CTL_PARENB_m | RP2_TXRX_CTL_nPARODD_m |
+		RP2_TXRX_CTL_CMSPAR_m | RP2_TXRX_CTL_DTRFLOW_m |
+		RP2_TXRX_CTL_DSRFLOW_m | RP2_TXRX_CTL_RTSFLOW_m |
+		RP2_TXRX_CTL_CTSFLOW_m,
+		((cfl & PARENB) ? RP2_TXRX_CTL_PARENB_m : 0) |
+		((cfl & PARODD) ? 0 : RP2_TXRX_CTL_nPARODD_m) |
+		((cfl & CMSPAR) ? RP2_TXRX_CTL_CMSPAR_m : 0) |
+		((cfl & CRTSCTS) ? (RP2_TXRX_CTL_RTSFLOW_m |
+				    RP2_TXRX_CTL_CTSFLOW_m) : 0));
+
+	/* XON/XOFF software flow control */
+	writeb((ifl & IXON) ? RP2_TX_SWFLOW_ena : RP2_TX_SWFLOW_dis,
+	       up->ucode + RP2_TX_SWFLOW);
+	writeb((ifl & IXOFF) ? RP2_RX_SWFLOW_ena : RP2_RX_SWFLOW_dis,
+	       up->ucode + RP2_RX_SWFLOW);
+}
+
+static void rp2_uart_set_termios(struct uart_port *port,
+				 struct ktermios *new,
+				 struct ktermios *old)
+{
+	struct rp2_uart_port *up = port_to_up(port);
+	unsigned long flags;
+	unsigned int baud, baud_div;
+
+	baud = uart_get_baud_rate(port, new, old, 0, port->uartclk / 16);
+	baud_div = uart_get_divisor(port, baud);
+
+	if (tty_termios_baud_rate(new))
+		tty_termios_encode_baud_rate(new, baud, baud);
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	/* ignore all characters if CREAD is not set */
+	port->ignore_status_mask = (new->c_cflag & CREAD) ? 0 : RP2_DUMMY_READ;
+
+	__rp2_uart_set_termios(up, new->c_cflag, new->c_iflag, baud_div);
+	uart_update_timeout(port, new->c_cflag, baud);
+
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void rp2_rx_chars(struct rp2_uart_port *up)
+{
+	u16 bytes = readw(up->base + RP2_RX_FIFO_COUNT);
+	struct tty_port *port = &up->port.state->port;
+
+	for (; bytes != 0; bytes--) {
+		u32 byte = readw(up->base + RP2_DATA_BYTE) | RP2_DUMMY_READ;
+		char ch = byte & 0xff;
+
+		if (likely(!(byte & RP2_DATA_BYTE_EXCEPTION_MASK))) {
+			if (!uart_handle_sysrq_char(&up->port, ch))
+				uart_insert_char(&up->port, byte, 0, ch,
+						 TTY_NORMAL);
+		} else {
+			char flag = TTY_NORMAL;
+
+			if (byte & RP2_DATA_BYTE_BREAK_m)
+				flag = TTY_BREAK;
+			else if (byte & RP2_DATA_BYTE_ERR_FRAMING_m)
+				flag = TTY_FRAME;
+			else if (byte & RP2_DATA_BYTE_ERR_PARITY_m)
+				flag = TTY_PARITY;
+			uart_insert_char(&up->port, byte,
+					 RP2_DATA_BYTE_ERR_OVERRUN_m, ch, flag);
+		}
+		up->port.icount.rx++;
+	}
+
+	tty_flip_buffer_push(port);
+}
+
+static void rp2_tx_chars(struct rp2_uart_port *up)
+{
+	u16 max_tx = FIFO_SIZE - readw(up->base + RP2_TX_FIFO_COUNT);
+	struct circ_buf *xmit = &up->port.state->xmit;
+
+	if (uart_tx_stopped(&up->port)) {
+		rp2_uart_stop_tx(&up->port);
+		return;
+	}
+
+	for (; max_tx != 0; max_tx--) {
+		if (up->port.x_char) {
+			writeb(up->port.x_char, up->base + RP2_DATA_BYTE);
+			up->port.x_char = 0;
+			up->port.icount.tx++;
+			continue;
+		}
+		if (uart_circ_empty(xmit)) {
+			rp2_uart_stop_tx(&up->port);
+			break;
+		}
+		writeb(xmit->buf[xmit->tail], up->base + RP2_DATA_BYTE);
+		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+		up->port.icount.tx++;
+	}
+
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(&up->port);
+}
+
+static void rp2_ch_interrupt(struct rp2_uart_port *up)
+{
+	u32 status;
+
+	spin_lock(&up->port.lock);
+
+	/*
+	 * The IRQ status bits are clear-on-write.  Other status bits in
+	 * this register aren't, so it's harmless to write to them.
+	 */
+	status = readl(up->base + RP2_CHAN_STAT);
+	writel(status, up->base + RP2_CHAN_STAT);
+
+	if (status & RP2_CHAN_STAT_RXDATA_m)
+		rp2_rx_chars(up);
+	if (status & RP2_CHAN_STAT_TXEMPTY_m)
+		rp2_tx_chars(up);
+	if (status & RP2_CHAN_STAT_MS_CHANGED_MASK)
+		wake_up_interruptible(&up->port.state->port.delta_msr_wait);
+
+	spin_unlock(&up->port.lock);
+}
+
+static int rp2_asic_interrupt(struct rp2_card *card, unsigned int asic_id)
+{
+	void __iomem *base = card->bar1 + RP2_ASIC_OFFSET(asic_id);
+	int ch, handled = 0;
+	unsigned long status = readl(base + RP2_CH_IRQ_STAT) &
+			       ~readl(base + RP2_CH_IRQ_MASK);
+
+	for_each_set_bit(ch, &status, PORTS_PER_ASIC) {
+		rp2_ch_interrupt(&card->ports[ch]);
+		handled++;
+	}
+	return handled;
+}
+
+static irqreturn_t rp2_uart_interrupt(int irq, void *dev_id)
+{
+	struct rp2_card *card = dev_id;
+	int handled;
+
+	handled = rp2_asic_interrupt(card, 0);
+	if (card->n_ports >= PORTS_PER_ASIC)
+		handled += rp2_asic_interrupt(card, 1);
+
+	return handled ? IRQ_HANDLED : IRQ_NONE;
+}
+
+static inline void rp2_flush_fifos(struct rp2_uart_port *up)
+{
+	rp2_rmw_set(up, RP2_UART_CTL,
+		    RP2_UART_CTL_FLUSH_RX_m | RP2_UART_CTL_FLUSH_TX_m);
+	readl(up->base + RP2_UART_CTL);
+	udelay(10);
+	rp2_rmw_clr(up, RP2_UART_CTL,
+		    RP2_UART_CTL_FLUSH_RX_m | RP2_UART_CTL_FLUSH_TX_m);
+}
+
+static int rp2_uart_startup(struct uart_port *port)
+{
+	struct rp2_uart_port *up = port_to_up(port);
+
+	rp2_flush_fifos(up);
+	rp2_rmw(up, RP2_TXRX_CTL, RP2_TXRX_CTL_MSRIRQ_m, RP2_TXRX_CTL_RXIRQ_m);
+	rp2_rmw(up, RP2_TXRX_CTL, RP2_TXRX_CTL_RX_TRIG_m,
+		RP2_TXRX_CTL_RX_TRIG_1);
+	rp2_rmw(up, RP2_CHAN_STAT, 0, 0);
+	rp2_mask_ch_irq(up, up->idx, 1);
+
+	return 0;
+}
+
+static void rp2_uart_shutdown(struct uart_port *port)
+{
+	struct rp2_uart_port *up = port_to_up(port);
+	unsigned long flags;
+
+	rp2_uart_break_ctl(port, 0);
+
+	spin_lock_irqsave(&port->lock, flags);
+	rp2_mask_ch_irq(up, up->idx, 0);
+	rp2_rmw(up, RP2_CHAN_STAT, 0, 0);
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static const char *rp2_uart_type(struct uart_port *port)
+{
+	return (port->type == PORT_RP2) ? "RocketPort 2 UART" : NULL;
+}
+
+static void rp2_uart_release_port(struct uart_port *port)
+{
+	/* Nothing to release ... */
+}
+
+static int rp2_uart_request_port(struct uart_port *port)
+{
+	/* UARTs always present */
+	return 0;
+}
+
+static void rp2_uart_config_port(struct uart_port *port, int flags)
+{
+	if (flags & UART_CONFIG_TYPE)
+		port->type = PORT_RP2;
+}
+
+static int rp2_uart_verify_port(struct uart_port *port,
+				   struct serial_struct *ser)
+{
+	if (ser->type != PORT_UNKNOWN && ser->type != PORT_RP2)
+		return -EINVAL;
+
+	return 0;
+}
+
+static const struct uart_ops rp2_uart_ops = {
+	.tx_empty	= rp2_uart_tx_empty,
+	.set_mctrl	= rp2_uart_set_mctrl,
+	.get_mctrl	= rp2_uart_get_mctrl,
+	.stop_tx	= rp2_uart_stop_tx,
+	.start_tx	= rp2_uart_start_tx,
+	.stop_rx	= rp2_uart_stop_rx,
+	.enable_ms	= rp2_uart_enable_ms,
+	.break_ctl	= rp2_uart_break_ctl,
+	.startup	= rp2_uart_startup,
+	.shutdown	= rp2_uart_shutdown,
+	.set_termios	= rp2_uart_set_termios,
+	.type		= rp2_uart_type,
+	.release_port	= rp2_uart_release_port,
+	.request_port	= rp2_uart_request_port,
+	.config_port	= rp2_uart_config_port,
+	.verify_port	= rp2_uart_verify_port,
+};
+
+static void rp2_reset_asic(struct rp2_card *card, unsigned int asic_id)
+{
+	void __iomem *base = card->bar1 + RP2_ASIC_OFFSET(asic_id);
+	u32 clk_cfg;
+
+	writew(1, base + RP2_GLOBAL_CMD);
+	readw(base + RP2_GLOBAL_CMD);
+	msleep(100);
+	writel(0, base + RP2_CLK_PRESCALER);
+
+	/* TDM clock configuration */
+	clk_cfg = readw(base + RP2_ASIC_CFG);
+	clk_cfg = (clk_cfg & ~BIT(8)) | BIT(9);
+	writew(clk_cfg, base + RP2_ASIC_CFG);
+
+	/* IRQ routing */
+	writel(ALL_PORTS_MASK, base + RP2_CH_IRQ_MASK);
+	writel(RP2_ASIC_IRQ_EN_m, base + RP2_ASIC_IRQ);
+}
+
+static void rp2_init_card(struct rp2_card *card)
+{
+	writel(4, card->bar0 + RP2_FPGA_CTL0);
+	writel(0, card->bar0 + RP2_FPGA_CTL1);
+
+	rp2_reset_asic(card, 0);
+	if (card->n_ports >= PORTS_PER_ASIC)
+		rp2_reset_asic(card, 1);
+
+	writel(RP2_IRQ_MASK_EN_m, card->bar0 + RP2_IRQ_MASK);
+}
+
+static void rp2_init_port(struct rp2_uart_port *up, const struct firmware *fw)
+{
+	int i;
+
+	writel(RP2_UART_CTL_RESET_CH_m, up->base + RP2_UART_CTL);
+	readl(up->base + RP2_UART_CTL);
+	udelay(1);
+
+	writel(0, up->base + RP2_TXRX_CTL);
+	writel(0, up->base + RP2_UART_CTL);
+	readl(up->base + RP2_UART_CTL);
+	udelay(1);
+
+	rp2_flush_fifos(up);
+
+	for (i = 0; i < min_t(int, fw->size, RP2_UCODE_BYTES); i++)
+		writeb(fw->data[i], up->ucode + i);
+
+	__rp2_uart_set_termios(up, CS8 | CREAD | CLOCAL, 0, DEFAULT_BAUD_DIV);
+	rp2_uart_set_mctrl(&up->port, 0);
+
+	writeb(RP2_RX_FIFO_ena, up->ucode + RP2_RX_FIFO);
+	rp2_rmw(up, RP2_UART_CTL, RP2_UART_CTL_MODE_m,
+		RP2_UART_CTL_XMIT_EN_m | RP2_UART_CTL_MODE_rs232);
+	rp2_rmw_set(up, RP2_TXRX_CTL,
+		    RP2_TXRX_CTL_TX_EN_m | RP2_TXRX_CTL_RX_EN_m);
+}
+
+static void rp2_remove_ports(struct rp2_card *card)
+{
+	int i;
+
+	for (i = 0; i < card->initialized_ports; i++)
+		uart_remove_one_port(&rp2_uart_driver, &card->ports[i].port);
+	card->initialized_ports = 0;
+}
+
+static void rp2_fw_cb(const struct firmware *fw, void *context)
+{
+	struct rp2_card *card = context;
+	resource_size_t phys_base;
+	int i, rc = -ENOENT;
+
+	if (!fw) {
+		dev_err(&card->pdev->dev, "cannot find '%s' firmware image\n",
+			RP2_FW_NAME);
+		goto no_fw;
+	}
+
+	phys_base = pci_resource_start(card->pdev, 1);
+
+	for (i = 0; i < card->n_ports; i++) {
+		struct rp2_uart_port *rp = &card->ports[i];
+		struct uart_port *p;
+		int j = (unsigned)i % PORTS_PER_ASIC;
+
+		rp->asic_base = card->bar1;
+		rp->base = card->bar1 + RP2_PORT_BASE + j*RP2_PORT_SPACING;
+		rp->ucode = card->bar1 + RP2_UCODE_BASE + j*RP2_UCODE_SPACING;
+		rp->card = card;
+		rp->idx = j;
+
+		p = &rp->port;
+		p->line = card->minor_start + i;
+		p->dev = &card->pdev->dev;
+		p->type = PORT_RP2;
+		p->iotype = UPIO_MEM32;
+		p->uartclk = UART_CLOCK;
+		p->regshift = 2;
+		p->fifosize = FIFO_SIZE;
+		p->ops = &rp2_uart_ops;
+		p->irq = card->pdev->irq;
+		p->membase = rp->base;
+		p->mapbase = phys_base + RP2_PORT_BASE + j*RP2_PORT_SPACING;
+
+		if (i >= PORTS_PER_ASIC) {
+			rp->asic_base += RP2_ASIC_SPACING;
+			rp->base += RP2_ASIC_SPACING;
+			rp->ucode += RP2_ASIC_SPACING;
+			p->mapbase += RP2_ASIC_SPACING;
+		}
+
+		rp2_init_port(rp, fw);
+		rc = uart_add_one_port(&rp2_uart_driver, p);
+		if (rc) {
+			dev_err(&card->pdev->dev,
+				"error registering port %d: %d\n", i, rc);
+			rp2_remove_ports(card);
+			break;
+		}
+		card->initialized_ports++;
+	}
+
+	release_firmware(fw);
+no_fw:
+	/*
+	 * rp2_fw_cb() is called from a workqueue long after rp2_probe()
+	 * has already returned success.  So if something failed here,
+	 * we'll just leave the now-dormant device in place until somebody
+	 * unbinds it.
+	 */
+	if (rc)
+		dev_warn(&card->pdev->dev, "driver initialization failed\n");
+
+	complete(&card->fw_loaded);
+}
+
+static int rp2_probe(struct pci_dev *pdev,
+				   const struct pci_device_id *id)
+{
+	struct rp2_card *card;
+	struct rp2_uart_port *ports;
+	void __iomem * const *bars;
+	int rc;
+
+	card = devm_kzalloc(&pdev->dev, sizeof(*card), GFP_KERNEL);
+	if (!card)
+		return -ENOMEM;
+	pci_set_drvdata(pdev, card);
+	spin_lock_init(&card->card_lock);
+	init_completion(&card->fw_loaded);
+
+	rc = pcim_enable_device(pdev);
+	if (rc)
+		return rc;
+
+	rc = pcim_iomap_regions_request_all(pdev, 0x03, DRV_NAME);
+	if (rc)
+		return rc;
+
+	bars = pcim_iomap_table(pdev);
+	card->bar0 = bars[0];
+	card->bar1 = bars[1];
+	card->pdev = pdev;
+
+	rp2_decode_cap(id, &card->n_ports, &card->smpte);
+	dev_info(&pdev->dev, "found new card with %d ports\n", card->n_ports);
+
+	card->minor_start = rp2_alloc_ports(card->n_ports);
+	if (card->minor_start < 0) {
+		dev_err(&pdev->dev,
+			"too many ports (try increasing CONFIG_SERIAL_RP2_NR_UARTS)\n");
+		return -EINVAL;
+	}
+
+	rp2_init_card(card);
+
+	ports = devm_kzalloc(&pdev->dev, sizeof(*ports) * card->n_ports,
+			     GFP_KERNEL);
+	if (!ports)
+		return -ENOMEM;
+	card->ports = ports;
+
+	rc = devm_request_irq(&pdev->dev, pdev->irq, rp2_uart_interrupt,
+			      IRQF_SHARED, DRV_NAME, card);
+	if (rc)
+		return rc;
+
+	/*
+	 * Only catastrophic errors (e.g. ENOMEM) are reported here.
+	 * If the FW image is missing, we'll find out in rp2_fw_cb()
+	 * and print an error message.
+	 */
+	rc = request_firmware_nowait(THIS_MODULE, 1, RP2_FW_NAME, &pdev->dev,
+				     GFP_KERNEL, card, rp2_fw_cb);
+	if (rc)
+		return rc;
+	dev_dbg(&pdev->dev, "waiting for firmware blob...\n");
+
+	return 0;
+}
+
+static void rp2_remove(struct pci_dev *pdev)
+{
+	struct rp2_card *card = pci_get_drvdata(pdev);
+
+	wait_for_completion(&card->fw_loaded);
+	rp2_remove_ports(card);
+}
+
+static DEFINE_PCI_DEVICE_TABLE(rp2_pci_tbl) = {
+
+	/* RocketPort INFINITY cards */
+
+	{ RP_ID(0x0040), RP_CAP(8,  0) }, /* INF Octa, RJ45, selectable */
+	{ RP_ID(0x0041), RP_CAP(32, 0) }, /* INF 32, ext interface */
+	{ RP_ID(0x0042), RP_CAP(8,  0) }, /* INF Octa, ext interface */
+	{ RP_ID(0x0043), RP_CAP(16, 0) }, /* INF 16, ext interface */
+	{ RP_ID(0x0044), RP_CAP(4,  0) }, /* INF Quad, DB, selectable */
+	{ RP_ID(0x0045), RP_CAP(8,  0) }, /* INF Octa, DB, selectable */
+	{ RP_ID(0x0046), RP_CAP(4,  0) }, /* INF Quad, ext interface */
+	{ RP_ID(0x0047), RP_CAP(4,  0) }, /* INF Quad, RJ45 */
+	{ RP_ID(0x004a), RP_CAP(4,  0) }, /* INF Plus, Quad */
+	{ RP_ID(0x004b), RP_CAP(8,  0) }, /* INF Plus, Octa */
+	{ RP_ID(0x004c), RP_CAP(8,  0) }, /* INF III, Octa */
+	{ RP_ID(0x004d), RP_CAP(4,  0) }, /* INF III, Quad */
+	{ RP_ID(0x004e), RP_CAP(2,  0) }, /* INF Plus, 2, RS232 */
+	{ RP_ID(0x004f), RP_CAP(2,  1) }, /* INF Plus, 2, SMPTE */
+	{ RP_ID(0x0050), RP_CAP(4,  0) }, /* INF Plus, Quad, RJ45 */
+	{ RP_ID(0x0051), RP_CAP(8,  0) }, /* INF Plus, Octa, RJ45 */
+	{ RP_ID(0x0052), RP_CAP(8,  1) }, /* INF Octa, SMPTE */
+
+	/* RocketPort EXPRESS cards */
+
+	{ RP_ID(0x0060), RP_CAP(8,  0) }, /* EXP Octa, RJ45, selectable */
+	{ RP_ID(0x0061), RP_CAP(32, 0) }, /* EXP 32, ext interface */
+	{ RP_ID(0x0062), RP_CAP(8,  0) }, /* EXP Octa, ext interface */
+	{ RP_ID(0x0063), RP_CAP(16, 0) }, /* EXP 16, ext interface */
+	{ RP_ID(0x0064), RP_CAP(4,  0) }, /* EXP Quad, DB, selectable */
+	{ RP_ID(0x0065), RP_CAP(8,  0) }, /* EXP Octa, DB, selectable */
+	{ RP_ID(0x0066), RP_CAP(4,  0) }, /* EXP Quad, ext interface */
+	{ RP_ID(0x0067), RP_CAP(4,  0) }, /* EXP Quad, RJ45 */
+	{ RP_ID(0x0068), RP_CAP(8,  0) }, /* EXP Octa, RJ11 */
+	{ RP_ID(0x0072), RP_CAP(8,  1) }, /* EXP Octa, SMPTE */
+	{ }
+};
+MODULE_DEVICE_TABLE(pci, rp2_pci_tbl);
+
+static struct pci_driver rp2_pci_driver = {
+	.name		= DRV_NAME,
+	.id_table	= rp2_pci_tbl,
+	.probe		= rp2_probe,
+	.remove		= rp2_remove,
+};
+
+static int __init rp2_uart_init(void)
+{
+	int rc;
+
+	rc = uart_register_driver(&rp2_uart_driver);
+	if (rc)
+		return rc;
+
+	rc = pci_register_driver(&rp2_pci_driver);
+	if (rc) {
+		uart_unregister_driver(&rp2_uart_driver);
+		return rc;
+	}
+
+	return 0;
+}
+
+static void __exit rp2_uart_exit(void)
+{
+	pci_unregister_driver(&rp2_pci_driver);
+	uart_unregister_driver(&rp2_uart_driver);
+}
+
+module_init(rp2_uart_init);
+module_exit(rp2_uart_exit);
+
+MODULE_DESCRIPTION("Comtrol RocketPort EXPRESS/INFINITY driver");
+MODULE_AUTHOR("Kevin Cernekee <cernekee@gmail.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_FIRMWARE(RP2_FW_NAME);
diff --git a/drivers/tty/serial/sa1100.c b/drivers/tty/serial/sa1100.c
index 5d4b9b449b4..af6b3e3ad24 100644
--- a/drivers/tty/serial/sa1100.c
+++ b/drivers/tty/serial/sa1100.c
@@ -188,7 +188,6 @@ static void sa1100_enable_ms(struct uart_port *port)
 static void
 sa1100_rx_chars(struct sa1100_port *sport)
 {
-	struct tty_struct *tty = sport->port.state->port.tty;
 	unsigned int status, ch, flg;
 
 	status = UTSR1_TO_SM(UART_GET_UTSR1(sport)) |
@@ -233,7 +232,7 @@ sa1100_rx_chars(struct sa1100_port *sport)
 		status = UTSR1_TO_SM(UART_GET_UTSR1(sport)) |
 			 UTSR0_TO_SM(UART_GET_UTSR0(sport));
 	}
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&sport->port.state->port);
 }
 
 static void sa1100_tx_chars(struct sa1100_port *sport)
diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index e514b3a4dc5..2769a38d15b 100644
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -47,7 +47,6 @@
 #include <asm/irq.h>
 
 #include <mach/hardware.h>
-#include <mach/map.h>
 
 #include <plat/regs-serial.h>
 #include <plat/clock.h>
@@ -221,7 +220,6 @@ s3c24xx_serial_rx_chars(int irq, void *dev_id)
 {
 	struct s3c24xx_uart_port *ourport = dev_id;
 	struct uart_port *port = &ourport->port;
-	struct tty_struct *tty = port->state->port.tty;
 	unsigned int ufcon, ch, flag, ufstat, uerstat;
 	unsigned long flags;
 	int max_count = 64;
@@ -299,7 +297,7 @@ s3c24xx_serial_rx_chars(int irq, void *dev_id)
  ignore_char:
 		continue;
 	}
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&port->state->port);
 
  out:
 	spin_unlock_irqrestore(&port->lock, flags);
@@ -1143,8 +1141,13 @@ static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
 
 	dbg("resource %p (%lx..%lx)\n", res, res->start, res->end);
 
+	port->membase = devm_ioremap(port->dev, res->start, resource_size(res));
+	if (!port->membase) {
+		dev_err(port->dev, "failed to remap controller address\n");
+		return -EBUSY;
+	}
+
 	port->mapbase = res->start;
-	port->membase = S3C_VA_UART + (res->start & 0xfffff);
 	ret = platform_get_irq(platdev, 0);
 	if (ret < 0)
 		port->irq = 0;
@@ -1724,8 +1727,6 @@ static const struct of_device_id s3c24xx_uart_dt_match[] = {
 	{},
 };
 MODULE_DEVICE_TABLE(of, s3c24xx_uart_dt_match);
-#else
-#define s3c24xx_uart_dt_match NULL
 #endif
 
 static struct platform_driver samsung_serial_driver = {
@@ -1736,7 +1737,7 @@ static struct platform_driver samsung_serial_driver = {
 		.name	= "samsung-uart",
 		.owner	= THIS_MODULE,
 		.pm	= SERIAL_SAMSUNG_PM_OPS,
-		.of_match_table	= s3c24xx_uart_dt_match,
+		.of_match_table	= of_match_ptr(s3c24xx_uart_dt_match),
 	},
 };
 
diff --git a/drivers/tty/serial/sb1250-duart.c b/drivers/tty/serial/sb1250-duart.c
index f76b1688c5c..a7cdec2962d 100644
--- a/drivers/tty/serial/sb1250-duart.c
+++ b/drivers/tty/serial/sb1250-duart.c
@@ -384,7 +384,7 @@ static void sbd_receive_chars(struct sbd_port *sport)
 		uart_insert_char(uport, status, M_DUART_OVRUN_ERR, ch, flag);
 	}
 
-	tty_flip_buffer_push(uport->state->port.tty);
+	tty_flip_buffer_push(&uport->state->port);
 }
 
 static void sbd_transmit_chars(struct sbd_port *sport)
diff --git a/drivers/tty/serial/sc26xx.c b/drivers/tty/serial/sc26xx.c
index aced1dd923d..c9735680762 100644
--- a/drivers/tty/serial/sc26xx.c
+++ b/drivers/tty/serial/sc26xx.c
@@ -136,16 +136,17 @@ static void sc26xx_disable_irq(struct uart_port *port, int mask)
 	WRITE_SC(port, IMR, up->imr);
 }
 
-static struct tty_struct *receive_chars(struct uart_port *port)
+static bool receive_chars(struct uart_port *port)
 {
-	struct tty_struct *tty = NULL;
+	struct tty_port *tport = NULL;
 	int limit = 10000;
 	unsigned char ch;
 	char flag;
 	u8 status;
 
+	/* FIXME what is this trying to achieve? */
 	if (port->state != NULL)		/* Unopened serial console */
-		tty = port->state->port.tty;
+		tport = &port->state->port;
 
 	while (limit-- > 0) {
 		status = READ_SC_PORT(port, SR);
@@ -185,9 +186,9 @@ static struct tty_struct *receive_chars(struct uart_port *port)
 		if (status & port->ignore_status_mask)
 			continue;
 
-		tty_insert_flip_char(tty, ch, flag);
+		tty_insert_flip_char(tport, ch, flag);
 	}
-	return tty;
+	return !!tport;
 }
 
 static void transmit_chars(struct uart_port *port)
@@ -217,36 +218,36 @@ static void transmit_chars(struct uart_port *port)
 static irqreturn_t sc26xx_interrupt(int irq, void *dev_id)
 {
 	struct uart_sc26xx_port *up = dev_id;
-	struct tty_struct *tty;
 	unsigned long flags;
+	bool push;
 	u8 isr;
 
 	spin_lock_irqsave(&up->port[0].lock, flags);
 
-	tty = NULL;
+	push = false;
 	isr = READ_SC(&up->port[0], ISR);
 	if (isr & ISR_TXRDYA)
 	    transmit_chars(&up->port[0]);
 	if (isr & ISR_RXRDYA)
-	    tty = receive_chars(&up->port[0]);
+	    push = receive_chars(&up->port[0]);
 
 	spin_unlock(&up->port[0].lock);
 
-	if (tty)
-		tty_flip_buffer_push(tty);
+	if (push)
+		tty_flip_buffer_push(&up->port[0].state->port);
 
 	spin_lock(&up->port[1].lock);
 
-	tty = NULL;
+	push = false;
 	if (isr & ISR_TXRDYB)
 	    transmit_chars(&up->port[1]);
 	if (isr & ISR_RXRDYB)
-	    tty = receive_chars(&up->port[1]);
+	    push = receive_chars(&up->port[1]);
 
 	spin_unlock_irqrestore(&up->port[1].lock, flags);
 
-	if (tty)
-		tty_flip_buffer_push(tty);
+	if (push)
+		tty_flip_buffer_push(&up->port[1].state->port);
 
 	return IRQ_HANDLED;
 }
diff --git a/drivers/tty/serial/sccnxp.c b/drivers/tty/serial/sccnxp.c
index e869eab180b..08dbfb88d42 100644
--- a/drivers/tty/serial/sccnxp.c
+++ b/drivers/tty/serial/sccnxp.c
@@ -24,8 +24,9 @@
 #include <linux/io.h>
 #include <linux/tty.h>
 #include <linux/tty_flip.h>
+#include <linux/spinlock.h>
 #include <linux/platform_device.h>
-#include <linux/platform_data/sccnxp.h>
+#include <linux/platform_data/serial-sccnxp.h>
 
 #define SCCNXP_NAME			"uart-sccnxp"
 #define SCCNXP_MAJOR			204
@@ -107,6 +108,7 @@ enum {
 struct sccnxp_port {
 	struct uart_driver	uart;
 	struct uart_port	port[SCCNXP_MAX_UARTS];
+	bool			opened[SCCNXP_MAX_UARTS];
 
 	const char		*name;
 	int			irq;
@@ -123,7 +125,10 @@ struct sccnxp_port {
 	struct console		console;
 #endif
 
-	struct mutex		sccnxp_mutex;
+	spinlock_t		lock;
+
+	bool			poll;
+	struct timer_list	timer;
 
 	struct sccnxp_pdata	pdata;
 };
@@ -175,14 +180,12 @@ static int sccnxp_update_best_err(int a, int b, int *besterr)
 	return 1;
 }
 
-struct baud_table {
+static const struct {
 	u8	csr;
 	u8	acr;
 	u8	mr0;
 	int	baud;
-};
-
-const struct baud_table baud_std[] = {
+} baud_std[] = {
 	{ 0,	ACR_BAUD0,	MR0_BAUD_NORMAL,	50, },
 	{ 0,	ACR_BAUD1,	MR0_BAUD_NORMAL,	75, },
 	{ 1,	ACR_BAUD0,	MR0_BAUD_NORMAL,	110, },
@@ -286,10 +289,6 @@ static void sccnxp_handle_rx(struct uart_port *port)
 {
 	u8 sr;
 	unsigned int ch, flag;
-	struct tty_struct *tty = tty_port_tty_get(&port->state->port);
-
-	if (!tty)
-		return;
 
 	for (;;) {
 		sr = sccnxp_port_read(port, SCCNXP_SR_REG);
@@ -305,14 +304,19 @@ static void sccnxp_handle_rx(struct uart_port *port)
 		if (unlikely(sr)) {
 			if (sr & SR_BRK) {
 				port->icount.brk++;
+				sccnxp_port_write(port, SCCNXP_CR_REG,
+						  CR_CMD_BREAK_RESET);
 				if (uart_handle_break(port))
 					continue;
 			} else if (sr & SR_PE)
 				port->icount.parity++;
 			else if (sr & SR_FE)
 				port->icount.frame++;
-			else if (sr & SR_OVR)
+			else if (sr & SR_OVR) {
 				port->icount.overrun++;
+				sccnxp_port_write(port, SCCNXP_CR_REG,
+						  CR_CMD_STATUS_RESET);
+			}
 
 			sr &= port->read_status_mask;
 			if (sr & SR_BRK)
@@ -334,9 +338,7 @@ static void sccnxp_handle_rx(struct uart_port *port)
 		uart_insert_char(port, sr, SR_OVR, ch, flag);
 	}
 
-	tty_flip_buffer_push(tty);
-
-	tty_kref_put(tty);
+	tty_flip_buffer_push(&port->state->port);
 }
 
 static void sccnxp_handle_tx(struct uart_port *port)
@@ -378,31 +380,48 @@ static void sccnxp_handle_tx(struct uart_port *port)
 		uart_write_wakeup(port);
 }
 
-static irqreturn_t sccnxp_ist(int irq, void *dev_id)
+static void sccnxp_handle_events(struct sccnxp_port *s)
 {
 	int i;
 	u8 isr;
-	struct sccnxp_port *s = (struct sccnxp_port *)dev_id;
-
-	mutex_lock(&s->sccnxp_mutex);
 
-	for (;;) {
+	do {
 		isr = sccnxp_read(&s->port[0], SCCNXP_ISR_REG);
 		isr &= s->imr;
 		if (!isr)
 			break;
 
-		dev_dbg(s->port[0].dev, "IRQ status: 0x%02x\n", isr);
-
 		for (i = 0; i < s->uart.nr; i++) {
-			if (isr & ISR_RXRDY(i))
+			if (s->opened[i] && (isr & ISR_RXRDY(i)))
 				sccnxp_handle_rx(&s->port[i]);
-			if (isr & ISR_TXRDY(i))
+			if (s->opened[i] && (isr & ISR_TXRDY(i)))
 				sccnxp_handle_tx(&s->port[i]);
 		}
-	}
+	} while (1);
+}
+
+static void sccnxp_timer(unsigned long data)
+{
+	struct sccnxp_port *s = (struct sccnxp_port *)data;
+	unsigned long flags;
 
-	mutex_unlock(&s->sccnxp_mutex);
+	spin_lock_irqsave(&s->lock, flags);
+	sccnxp_handle_events(s);
+	spin_unlock_irqrestore(&s->lock, flags);
+
+	if (!timer_pending(&s->timer))
+		mod_timer(&s->timer, jiffies +
+			  usecs_to_jiffies(s->pdata.poll_time_us));
+}
+
+static irqreturn_t sccnxp_ist(int irq, void *dev_id)
+{
+	struct sccnxp_port *s = (struct sccnxp_port *)dev_id;
+	unsigned long flags;
+
+	spin_lock_irqsave(&s->lock, flags);
+	sccnxp_handle_events(s);
+	spin_unlock_irqrestore(&s->lock, flags);
 
 	return IRQ_HANDLED;
 }
@@ -410,8 +429,9 @@ static irqreturn_t sccnxp_ist(int irq, void *dev_id)
 static void sccnxp_start_tx(struct uart_port *port)
 {
 	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+	unsigned long flags;
 
-	mutex_lock(&s->sccnxp_mutex);
+	spin_lock_irqsave(&s->lock, flags);
 
 	/* Set direction to output */
 	if (s->flags & SCCNXP_HAVE_IO)
@@ -419,7 +439,7 @@ static void sccnxp_start_tx(struct uart_port *port)
 
 	sccnxp_enable_irq(port, IMR_TXRDY);
 
-	mutex_unlock(&s->sccnxp_mutex);
+	spin_unlock_irqrestore(&s->lock, flags);
 }
 
 static void sccnxp_stop_tx(struct uart_port *port)
@@ -430,20 +450,22 @@ static void sccnxp_stop_tx(struct uart_port *port)
 static void sccnxp_stop_rx(struct uart_port *port)
 {
 	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+	unsigned long flags;
 
-	mutex_lock(&s->sccnxp_mutex);
+	spin_lock_irqsave(&s->lock, flags);
 	sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_DISABLE);
-	mutex_unlock(&s->sccnxp_mutex);
+	spin_unlock_irqrestore(&s->lock, flags);
 }
 
 static unsigned int sccnxp_tx_empty(struct uart_port *port)
 {
 	u8 val;
+	unsigned long flags;
 	struct sccnxp_port *s = dev_get_drvdata(port->dev);
 
-	mutex_lock(&s->sccnxp_mutex);
+	spin_lock_irqsave(&s->lock, flags);
 	val = sccnxp_port_read(port, SCCNXP_SR_REG);
-	mutex_unlock(&s->sccnxp_mutex);
+	spin_unlock_irqrestore(&s->lock, flags);
 
 	return (val & SR_TXEMT) ? TIOCSER_TEMT : 0;
 }
@@ -456,28 +478,30 @@ static void sccnxp_enable_ms(struct uart_port *port)
 static void sccnxp_set_mctrl(struct uart_port *port, unsigned int mctrl)
 {
 	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+	unsigned long flags;
 
 	if (!(s->flags & SCCNXP_HAVE_IO))
 		return;
 
-	mutex_lock(&s->sccnxp_mutex);
+	spin_lock_irqsave(&s->lock, flags);
 
 	sccnxp_set_bit(port, DTR_OP, mctrl & TIOCM_DTR);
 	sccnxp_set_bit(port, RTS_OP, mctrl & TIOCM_RTS);
 
-	mutex_unlock(&s->sccnxp_mutex);
+	spin_unlock_irqrestore(&s->lock, flags);
 }
 
 static unsigned int sccnxp_get_mctrl(struct uart_port *port)
 {
 	u8 bitmask, ipr;
+	unsigned long flags;
 	struct sccnxp_port *s = dev_get_drvdata(port->dev);
 	unsigned int mctrl = TIOCM_DSR | TIOCM_CTS | TIOCM_CAR;
 
 	if (!(s->flags & SCCNXP_HAVE_IO))
 		return mctrl;
 
-	mutex_lock(&s->sccnxp_mutex);
+	spin_lock_irqsave(&s->lock, flags);
 
 	ipr = ~sccnxp_read(port, SCCNXP_IPCR_REG);
 
@@ -506,7 +530,7 @@ static unsigned int sccnxp_get_mctrl(struct uart_port *port)
 		mctrl |= (ipr & bitmask) ? TIOCM_RNG : 0;
 	}
 
-	mutex_unlock(&s->sccnxp_mutex);
+	spin_unlock_irqrestore(&s->lock, flags);
 
 	return mctrl;
 }
@@ -514,21 +538,23 @@ static unsigned int sccnxp_get_mctrl(struct uart_port *port)
 static void sccnxp_break_ctl(struct uart_port *port, int break_state)
 {
 	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+	unsigned long flags;
 
-	mutex_lock(&s->sccnxp_mutex);
+	spin_lock_irqsave(&s->lock, flags);
 	sccnxp_port_write(port, SCCNXP_CR_REG, break_state ?
 			  CR_CMD_START_BREAK : CR_CMD_STOP_BREAK);
-	mutex_unlock(&s->sccnxp_mutex);
+	spin_unlock_irqrestore(&s->lock, flags);
 }
 
 static void sccnxp_set_termios(struct uart_port *port,
 			       struct ktermios *termios, struct ktermios *old)
 {
 	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+	unsigned long flags;
 	u8 mr1, mr2;
 	int baud;
 
-	mutex_lock(&s->sccnxp_mutex);
+	spin_lock_irqsave(&s->lock, flags);
 
 	/* Mask termios capabilities we don't support */
 	termios->c_cflag &= ~CMSPAR;
@@ -595,20 +621,22 @@ static void sccnxp_set_termios(struct uart_port *port,
 	/* Update timeout according to new baud rate */
 	uart_update_timeout(port, termios->c_cflag, baud);
 
+	/* Report actual baudrate back to core */
 	if (tty_termios_baud_rate(termios))
 		tty_termios_encode_baud_rate(termios, baud, baud);
 
 	/* Enable RX & TX */
 	sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_ENABLE | CR_TX_ENABLE);
 
-	mutex_unlock(&s->sccnxp_mutex);
+	spin_unlock_irqrestore(&s->lock, flags);
 }
 
 static int sccnxp_startup(struct uart_port *port)
 {
 	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+	unsigned long flags;
 
-	mutex_lock(&s->sccnxp_mutex);
+	spin_lock_irqsave(&s->lock, flags);
 
 	if (s->flags & SCCNXP_HAVE_IO) {
 		/* Outputs are controlled manually */
@@ -627,7 +655,9 @@ static int sccnxp_startup(struct uart_port *port)
 	/* Enable RX interrupt */
 	sccnxp_enable_irq(port, IMR_RXRDY);
 
-	mutex_unlock(&s->sccnxp_mutex);
+	s->opened[port->line] = 1;
+
+	spin_unlock_irqrestore(&s->lock, flags);
 
 	return 0;
 }
@@ -635,8 +665,11 @@ static int sccnxp_startup(struct uart_port *port)
 static void sccnxp_shutdown(struct uart_port *port)
 {
 	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+	unsigned long flags;
 
-	mutex_lock(&s->sccnxp_mutex);
+	spin_lock_irqsave(&s->lock, flags);
+
+	s->opened[port->line] = 0;
 
 	/* Disable interrupts */
 	sccnxp_disable_irq(port, IMR_TXRDY | IMR_RXRDY);
@@ -648,7 +681,7 @@ static void sccnxp_shutdown(struct uart_port *port)
 	if (s->flags & SCCNXP_HAVE_IO)
 		sccnxp_set_bit(port, DIR_OP, 0);
 
-	mutex_unlock(&s->sccnxp_mutex);
+	spin_unlock_irqrestore(&s->lock, flags);
 }
 
 static const char *sccnxp_type(struct uart_port *port)
@@ -722,10 +755,11 @@ static void sccnxp_console_write(struct console *co, const char *c, unsigned n)
 {
 	struct sccnxp_port *s = (struct sccnxp_port *)co->data;
 	struct uart_port *port = &s->port[co->index];
+	unsigned long flags;
 
-	mutex_lock(&s->sccnxp_mutex);
+	spin_lock_irqsave(&s->lock, flags);
 	uart_console_write(port, c, n, sccnxp_console_putchar);
-	mutex_unlock(&s->sccnxp_mutex);
+	spin_unlock_irqrestore(&s->lock, flags);
 }
 
 static int sccnxp_console_setup(struct console *co, char *options)
@@ -764,7 +798,7 @@ static int sccnxp_probe(struct platform_device *pdev)
 	}
 	platform_set_drvdata(pdev, s);
 
-	mutex_init(&s->sccnxp_mutex);
+	spin_lock_init(&s->lock);
 
 	/* Individual chip settings */
 	switch (chiptype) {
@@ -861,11 +895,19 @@ static int sccnxp_probe(struct platform_device *pdev)
 	} else
 		memcpy(&s->pdata, pdata, sizeof(struct sccnxp_pdata));
 
-	s->irq = platform_get_irq(pdev, 0);
-	if (s->irq <= 0) {
-		dev_err(&pdev->dev, "Missing irq resource data\n");
-		ret = -ENXIO;
-		goto err_out;
+	if (s->pdata.poll_time_us) {
+		dev_info(&pdev->dev, "Using poll mode, resolution %u usecs\n",
+			 s->pdata.poll_time_us);
+		s->poll = 1;
+	}
+
+	if (!s->poll) {
+		s->irq = platform_get_irq(pdev, 0);
+		if (s->irq < 0) {
+			dev_err(&pdev->dev, "Missing irq resource data\n");
+			ret = -ENXIO;
+			goto err_out;
+		}
 	}
 
 	/* Check input frequency */
@@ -929,13 +971,23 @@ static int sccnxp_probe(struct platform_device *pdev)
 	if (s->pdata.init)
 		s->pdata.init();
 
-	ret = devm_request_threaded_irq(&pdev->dev, s->irq, NULL, sccnxp_ist,
-					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
-					dev_name(&pdev->dev), s);
-	if (!ret)
+	if (!s->poll) {
+		ret = devm_request_threaded_irq(&pdev->dev, s->irq, NULL,
+						sccnxp_ist,
+						IRQF_TRIGGER_FALLING |
+						IRQF_ONESHOT,
+						dev_name(&pdev->dev), s);
+		if (!ret)
+			return 0;
+
+		dev_err(&pdev->dev, "Unable to reguest IRQ %i\n", s->irq);
+	} else {
+		init_timer(&s->timer);
+		setup_timer(&s->timer, sccnxp_timer, (unsigned long)s);
+		mod_timer(&s->timer, jiffies +
+			  usecs_to_jiffies(s->pdata.poll_time_us));
 		return 0;
-
-	dev_err(&pdev->dev, "Unable to reguest IRQ %i\n", s->irq);
+	}
 
 err_out:
 	platform_set_drvdata(pdev, NULL);
@@ -948,7 +1000,10 @@ static int sccnxp_remove(struct platform_device *pdev)
 	int i;
 	struct sccnxp_port *s = platform_get_drvdata(pdev);
 
-	devm_free_irq(&pdev->dev, s->irq, s);
+	if (!s->poll)
+		devm_free_irq(&pdev->dev, s->irq, s);
+	else
+		del_timer_sync(&s->timer);
 
 	for (i = 0; i < s->uart.nr; i++)
 		uart_remove_one_port(&s->uart, &s->port[i]);
diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c
new file mode 100644
index 00000000000..372de8ade76
--- /dev/null
+++ b/drivers/tty/serial/serial-tegra.c
@@ -0,0 +1,1401 @@
+/*
+ * serial_tegra.c
+ *
+ * High-speed serial driver for NVIDIA Tegra SoCs
+ *
+ * Copyright (c) 2012-2013, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * Author: Laxman Dewangan <ldewangan@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/clk.h>
+#include <linux/debugfs.h>
+#include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmapool.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/pagemap.h>
+#include <linux/platform_device.h>
+#include <linux/serial.h>
+#include <linux/serial_8250.h>
+#include <linux/serial_core.h>
+#include <linux/serial_reg.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/termios.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+
+#include <linux/clk/tegra.h>
+
+#define TEGRA_UART_TYPE				"TEGRA_UART"
+#define TX_EMPTY_STATUS				(UART_LSR_TEMT | UART_LSR_THRE)
+#define BYTES_TO_ALIGN(x)			((unsigned long)(x) & 0x3)
+
+#define TEGRA_UART_RX_DMA_BUFFER_SIZE		4096
+#define TEGRA_UART_LSR_TXFIFO_FULL		0x100
+#define TEGRA_UART_IER_EORD			0x20
+#define TEGRA_UART_MCR_RTS_EN			0x40
+#define TEGRA_UART_MCR_CTS_EN			0x20
+#define TEGRA_UART_LSR_ANY			(UART_LSR_OE | UART_LSR_BI | \
+						UART_LSR_PE | UART_LSR_FE)
+#define TEGRA_UART_IRDA_CSR			0x08
+#define TEGRA_UART_SIR_ENABLED			0x80
+
+#define TEGRA_UART_TX_PIO			1
+#define TEGRA_UART_TX_DMA			2
+#define TEGRA_UART_MIN_DMA			16
+#define TEGRA_UART_FIFO_SIZE			32
+
+/*
+ * Tx fifo trigger level setting in tegra uart is in
+ * reverse way then conventional uart.
+ */
+#define TEGRA_UART_TX_TRIG_16B			0x00
+#define TEGRA_UART_TX_TRIG_8B			0x10
+#define TEGRA_UART_TX_TRIG_4B			0x20
+#define TEGRA_UART_TX_TRIG_1B			0x30
+
+#define TEGRA_UART_MAXIMUM			5
+
+/* Default UART setting when started: 115200 no parity, stop, 8 data bits */
+#define TEGRA_UART_DEFAULT_BAUD			115200
+#define TEGRA_UART_DEFAULT_LSR			UART_LCR_WLEN8
+
+/* Tx transfer mode */
+#define TEGRA_TX_PIO				1
+#define TEGRA_TX_DMA				2
+
+/**
+ * tegra_uart_chip_data: SOC specific data.
+ *
+ * @tx_fifo_full_status: Status flag available for checking tx fifo full.
+ * @allow_txfifo_reset_fifo_mode: allow_tx fifo reset with fifo mode or not.
+ *			Tegra30 does not allow this.
+ * @support_clk_src_div: Clock source support the clock divider.
+ */
+struct tegra_uart_chip_data {
+	bool	tx_fifo_full_status;
+	bool	allow_txfifo_reset_fifo_mode;
+	bool	support_clk_src_div;
+};
+
+struct tegra_uart_port {
+	struct uart_port			uport;
+	const struct tegra_uart_chip_data	*cdata;
+
+	struct clk				*uart_clk;
+	unsigned int				current_baud;
+
+	/* Register shadow */
+	unsigned long				fcr_shadow;
+	unsigned long				mcr_shadow;
+	unsigned long				lcr_shadow;
+	unsigned long				ier_shadow;
+	bool					rts_active;
+
+	int					tx_in_progress;
+	unsigned int				tx_bytes;
+
+	bool					enable_modem_interrupt;
+
+	bool					rx_timeout;
+	int					rx_in_progress;
+	int					symb_bit;
+	int					dma_req_sel;
+
+	struct dma_chan				*rx_dma_chan;
+	struct dma_chan				*tx_dma_chan;
+	dma_addr_t				rx_dma_buf_phys;
+	dma_addr_t				tx_dma_buf_phys;
+	unsigned char				*rx_dma_buf_virt;
+	unsigned char				*tx_dma_buf_virt;
+	struct dma_async_tx_descriptor		*tx_dma_desc;
+	struct dma_async_tx_descriptor		*rx_dma_desc;
+	dma_cookie_t				tx_cookie;
+	dma_cookie_t				rx_cookie;
+	int					tx_bytes_requested;
+	int					rx_bytes_requested;
+};
+
+static void tegra_uart_start_next_tx(struct tegra_uart_port *tup);
+static int tegra_uart_start_rx_dma(struct tegra_uart_port *tup);
+
+static inline unsigned long tegra_uart_read(struct tegra_uart_port *tup,
+		unsigned long reg)
+{
+	return readl(tup->uport.membase + (reg << tup->uport.regshift));
+}
+
+static inline void tegra_uart_write(struct tegra_uart_port *tup, unsigned val,
+	unsigned long reg)
+{
+	writel(val, tup->uport.membase + (reg << tup->uport.regshift));
+}
+
+static inline struct tegra_uart_port *to_tegra_uport(struct uart_port *u)
+{
+	return container_of(u, struct tegra_uart_port, uport);
+}
+
+static unsigned int tegra_uart_get_mctrl(struct uart_port *u)
+{
+	struct tegra_uart_port *tup = to_tegra_uport(u);
+
+	/*
+	 * RI - Ring detector is active
+	 * CD/DCD/CAR - Carrier detect is always active. For some reason
+	 *	linux has different names for carrier detect.
+	 * DSR - Data Set ready is active as the hardware doesn't support it.
+	 *	Don't know if the linux support this yet?
+	 * CTS - Clear to send. Always set to active, as the hardware handles
+	 *	CTS automatically.
+	 */
+	if (tup->enable_modem_interrupt)
+		return TIOCM_RI | TIOCM_CD | TIOCM_DSR | TIOCM_CTS;
+	return TIOCM_CTS;
+}
+
+static void set_rts(struct tegra_uart_port *tup, bool active)
+{
+	unsigned long mcr;
+
+	mcr = tup->mcr_shadow;
+	if (active)
+		mcr |= TEGRA_UART_MCR_RTS_EN;
+	else
+		mcr &= ~TEGRA_UART_MCR_RTS_EN;
+	if (mcr != tup->mcr_shadow) {
+		tegra_uart_write(tup, mcr, UART_MCR);
+		tup->mcr_shadow = mcr;
+	}
+	return;
+}
+
+static void set_dtr(struct tegra_uart_port *tup, bool active)
+{
+	unsigned long mcr;
+
+	mcr = tup->mcr_shadow;
+	if (active)
+		mcr |= UART_MCR_DTR;
+	else
+		mcr &= ~UART_MCR_DTR;
+	if (mcr != tup->mcr_shadow) {
+		tegra_uart_write(tup, mcr, UART_MCR);
+		tup->mcr_shadow = mcr;
+	}
+	return;
+}
+
+static void tegra_uart_set_mctrl(struct uart_port *u, unsigned int mctrl)
+{
+	struct tegra_uart_port *tup = to_tegra_uport(u);
+	unsigned long mcr;
+	int dtr_enable;
+
+	mcr = tup->mcr_shadow;
+	tup->rts_active = !!(mctrl & TIOCM_RTS);
+	set_rts(tup, tup->rts_active);
+
+	dtr_enable = !!(mctrl & TIOCM_DTR);
+	set_dtr(tup, dtr_enable);
+	return;
+}
+
+static void tegra_uart_break_ctl(struct uart_port *u, int break_ctl)
+{
+	struct tegra_uart_port *tup = to_tegra_uport(u);
+	unsigned long lcr;
+
+	lcr = tup->lcr_shadow;
+	if (break_ctl)
+		lcr |= UART_LCR_SBC;
+	else
+		lcr &= ~UART_LCR_SBC;
+	tegra_uart_write(tup, lcr, UART_LCR);
+	tup->lcr_shadow = lcr;
+}
+
+/* Wait for a symbol-time. */
+static void tegra_uart_wait_sym_time(struct tegra_uart_port *tup,
+		unsigned int syms)
+{
+	if (tup->current_baud)
+		udelay(DIV_ROUND_UP(syms * tup->symb_bit * 1000000,
+			tup->current_baud));
+}
+
+static void tegra_uart_fifo_reset(struct tegra_uart_port *tup, u8 fcr_bits)
+{
+	unsigned long fcr = tup->fcr_shadow;
+
+	if (tup->cdata->allow_txfifo_reset_fifo_mode) {
+		fcr |= fcr_bits & (UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
+		tegra_uart_write(tup, fcr, UART_FCR);
+	} else {
+		fcr &= ~UART_FCR_ENABLE_FIFO;
+		tegra_uart_write(tup, fcr, UART_FCR);
+		udelay(60);
+		fcr |= fcr_bits & (UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
+		tegra_uart_write(tup, fcr, UART_FCR);
+		fcr |= UART_FCR_ENABLE_FIFO;
+		tegra_uart_write(tup, fcr, UART_FCR);
+	}
+
+	/* Dummy read to ensure the write is posted */
+	tegra_uart_read(tup, UART_SCR);
+
+	/* Wait for the flush to propagate. */
+	tegra_uart_wait_sym_time(tup, 1);
+}
+
+static int tegra_set_baudrate(struct tegra_uart_port *tup, unsigned int baud)
+{
+	unsigned long rate;
+	unsigned int divisor;
+	unsigned long lcr;
+	int ret;
+
+	if (tup->current_baud == baud)
+		return 0;
+
+	if (tup->cdata->support_clk_src_div) {
+		rate = baud * 16;
+		ret = clk_set_rate(tup->uart_clk, rate);
+		if (ret < 0) {
+			dev_err(tup->uport.dev,
+				"clk_set_rate() failed for rate %lu\n", rate);
+			return ret;
+		}
+		divisor = 1;
+	} else {
+		rate = clk_get_rate(tup->uart_clk);
+		divisor = DIV_ROUND_CLOSEST(rate, baud * 16);
+	}
+
+	lcr = tup->lcr_shadow;
+	lcr |= UART_LCR_DLAB;
+	tegra_uart_write(tup, lcr, UART_LCR);
+
+	tegra_uart_write(tup, divisor & 0xFF, UART_TX);
+	tegra_uart_write(tup, ((divisor >> 8) & 0xFF), UART_IER);
+
+	lcr &= ~UART_LCR_DLAB;
+	tegra_uart_write(tup, lcr, UART_LCR);
+
+	/* Dummy read to ensure the write is posted */
+	tegra_uart_read(tup, UART_SCR);
+
+	tup->current_baud = baud;
+
+	/* wait two character intervals at new rate */
+	tegra_uart_wait_sym_time(tup, 2);
+	return 0;
+}
+
+static char tegra_uart_decode_rx_error(struct tegra_uart_port *tup,
+			unsigned long lsr)
+{
+	char flag = TTY_NORMAL;
+
+	if (unlikely(lsr & TEGRA_UART_LSR_ANY)) {
+		if (lsr & UART_LSR_OE) {
+			/* Overrrun error */
+			flag |= TTY_OVERRUN;
+			tup->uport.icount.overrun++;
+			dev_err(tup->uport.dev, "Got overrun errors\n");
+		} else if (lsr & UART_LSR_PE) {
+			/* Parity error */
+			flag |= TTY_PARITY;
+			tup->uport.icount.parity++;
+			dev_err(tup->uport.dev, "Got Parity errors\n");
+		} else if (lsr & UART_LSR_FE) {
+			flag |= TTY_FRAME;
+			tup->uport.icount.frame++;
+			dev_err(tup->uport.dev, "Got frame errors\n");
+		} else if (lsr & UART_LSR_BI) {
+			dev_err(tup->uport.dev, "Got Break\n");
+			tup->uport.icount.brk++;
+			/* If FIFO read error without any data, reset Rx FIFO */
+			if (!(lsr & UART_LSR_DR) && (lsr & UART_LSR_FIFOE))
+				tegra_uart_fifo_reset(tup, UART_FCR_CLEAR_RCVR);
+		}
+	}
+	return flag;
+}
+
+static int tegra_uart_request_port(struct uart_port *u)
+{
+	return 0;
+}
+
+static void tegra_uart_release_port(struct uart_port *u)
+{
+	/* Nothing to do here */
+}
+
+static void tegra_uart_fill_tx_fifo(struct tegra_uart_port *tup, int max_bytes)
+{
+	struct circ_buf *xmit = &tup->uport.state->xmit;
+	int i;
+
+	for (i = 0; i < max_bytes; i++) {
+		BUG_ON(uart_circ_empty(xmit));
+		if (tup->cdata->tx_fifo_full_status) {
+			unsigned long lsr = tegra_uart_read(tup, UART_LSR);
+			if ((lsr & TEGRA_UART_LSR_TXFIFO_FULL))
+				break;
+		}
+		tegra_uart_write(tup, xmit->buf[xmit->tail], UART_TX);
+		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+		tup->uport.icount.tx++;
+	}
+}
+
+static void tegra_uart_start_pio_tx(struct tegra_uart_port *tup,
+		unsigned int bytes)
+{
+	if (bytes > TEGRA_UART_MIN_DMA)
+		bytes = TEGRA_UART_MIN_DMA;
+
+	tup->tx_in_progress = TEGRA_UART_TX_PIO;
+	tup->tx_bytes = bytes;
+	tup->ier_shadow |= UART_IER_THRI;
+	tegra_uart_write(tup, tup->ier_shadow, UART_IER);
+}
+
+static void tegra_uart_tx_dma_complete(void *args)
+{
+	struct tegra_uart_port *tup = args;
+	struct circ_buf *xmit = &tup->uport.state->xmit;
+	struct dma_tx_state state;
+	unsigned long flags;
+	int count;
+
+	dmaengine_tx_status(tup->tx_dma_chan, tup->rx_cookie, &state);
+	count = tup->tx_bytes_requested - state.residue;
+	async_tx_ack(tup->tx_dma_desc);
+	spin_lock_irqsave(&tup->uport.lock, flags);
+	xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1);
+	tup->tx_in_progress = 0;
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(&tup->uport);
+	tegra_uart_start_next_tx(tup);
+	spin_unlock_irqrestore(&tup->uport.lock, flags);
+}
+
+static int tegra_uart_start_tx_dma(struct tegra_uart_port *tup,
+		unsigned long count)
+{
+	struct circ_buf *xmit = &tup->uport.state->xmit;
+	dma_addr_t tx_phys_addr;
+
+	dma_sync_single_for_device(tup->uport.dev, tup->tx_dma_buf_phys,
+				UART_XMIT_SIZE, DMA_TO_DEVICE);
+
+	tup->tx_bytes = count & ~(0xF);
+	tx_phys_addr = tup->tx_dma_buf_phys + xmit->tail;
+	tup->tx_dma_desc = dmaengine_prep_slave_single(tup->tx_dma_chan,
+				tx_phys_addr, tup->tx_bytes, DMA_MEM_TO_DEV,
+				DMA_PREP_INTERRUPT);
+	if (!tup->tx_dma_desc) {
+		dev_err(tup->uport.dev, "Not able to get desc for Tx\n");
+		return -EIO;
+	}
+
+	tup->tx_dma_desc->callback = tegra_uart_tx_dma_complete;
+	tup->tx_dma_desc->callback_param = tup;
+	tup->tx_in_progress = TEGRA_UART_TX_DMA;
+	tup->tx_bytes_requested = tup->tx_bytes;
+	tup->tx_cookie = dmaengine_submit(tup->tx_dma_desc);
+	dma_async_issue_pending(tup->tx_dma_chan);
+	return 0;
+}
+
+static void tegra_uart_start_next_tx(struct tegra_uart_port *tup)
+{
+	unsigned long tail;
+	unsigned long count;
+	struct circ_buf *xmit = &tup->uport.state->xmit;
+
+	tail = (unsigned long)&xmit->buf[xmit->tail];
+	count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
+	if (!count)
+		return;
+
+	if (count < TEGRA_UART_MIN_DMA)
+		tegra_uart_start_pio_tx(tup, count);
+	else if (BYTES_TO_ALIGN(tail) > 0)
+		tegra_uart_start_pio_tx(tup, BYTES_TO_ALIGN(tail));
+	else
+		tegra_uart_start_tx_dma(tup, count);
+}
+
+/* Called by serial core driver with u->lock taken. */
+static void tegra_uart_start_tx(struct uart_port *u)
+{
+	struct tegra_uart_port *tup = to_tegra_uport(u);
+	struct circ_buf *xmit = &u->state->xmit;
+
+	if (!uart_circ_empty(xmit) && !tup->tx_in_progress)
+		tegra_uart_start_next_tx(tup);
+}
+
+static unsigned int tegra_uart_tx_empty(struct uart_port *u)
+{
+	struct tegra_uart_port *tup = to_tegra_uport(u);
+	unsigned int ret = 0;
+	unsigned long flags;
+
+	spin_lock_irqsave(&u->lock, flags);
+	if (!tup->tx_in_progress) {
+		unsigned long lsr = tegra_uart_read(tup, UART_LSR);
+		if ((lsr & TX_EMPTY_STATUS) == TX_EMPTY_STATUS)
+			ret = TIOCSER_TEMT;
+	}
+	spin_unlock_irqrestore(&u->lock, flags);
+	return ret;
+}
+
+static void tegra_uart_stop_tx(struct uart_port *u)
+{
+	struct tegra_uart_port *tup = to_tegra_uport(u);
+	struct circ_buf *xmit = &tup->uport.state->xmit;
+	struct dma_tx_state state;
+	int count;
+
+	dmaengine_terminate_all(tup->tx_dma_chan);
+	dmaengine_tx_status(tup->tx_dma_chan, tup->tx_cookie, &state);
+	count = tup->tx_bytes_requested - state.residue;
+	async_tx_ack(tup->tx_dma_desc);
+	xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1);
+	tup->tx_in_progress = 0;
+	return;
+}
+
+static void tegra_uart_handle_tx_pio(struct tegra_uart_port *tup)
+{
+	struct circ_buf *xmit = &tup->uport.state->xmit;
+
+	tegra_uart_fill_tx_fifo(tup, tup->tx_bytes);
+	tup->tx_in_progress = 0;
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(&tup->uport);
+	tegra_uart_start_next_tx(tup);
+	return;
+}
+
+static void tegra_uart_handle_rx_pio(struct tegra_uart_port *tup,
+		struct tty_port *tty)
+{
+	do {
+		char flag = TTY_NORMAL;
+		unsigned long lsr = 0;
+		unsigned char ch;
+
+		lsr = tegra_uart_read(tup, UART_LSR);
+		if (!(lsr & UART_LSR_DR))
+			break;
+
+		flag = tegra_uart_decode_rx_error(tup, lsr);
+		ch = (unsigned char) tegra_uart_read(tup, UART_RX);
+		tup->uport.icount.rx++;
+
+		if (!uart_handle_sysrq_char(&tup->uport, ch) && tty)
+			tty_insert_flip_char(tty, ch, flag);
+	} while (1);
+
+	return;
+}
+
+static void tegra_uart_copy_rx_to_tty(struct tegra_uart_port *tup,
+		struct tty_port *tty, int count)
+{
+	int copied;
+
+	tup->uport.icount.rx += count;
+	if (!tty) {
+		dev_err(tup->uport.dev, "No tty port\n");
+		return;
+	}
+	dma_sync_single_for_cpu(tup->uport.dev, tup->rx_dma_buf_phys,
+				TEGRA_UART_RX_DMA_BUFFER_SIZE, DMA_FROM_DEVICE);
+	copied = tty_insert_flip_string(tty,
+			((unsigned char *)(tup->rx_dma_buf_virt)), count);
+	if (copied != count) {
+		WARN_ON(1);
+		dev_err(tup->uport.dev, "RxData copy to tty layer failed\n");
+	}
+	dma_sync_single_for_device(tup->uport.dev, tup->rx_dma_buf_phys,
+				TEGRA_UART_RX_DMA_BUFFER_SIZE, DMA_TO_DEVICE);
+}
+
+static void tegra_uart_rx_dma_complete(void *args)
+{
+	struct tegra_uart_port *tup = args;
+	struct uart_port *u = &tup->uport;
+	int count = tup->rx_bytes_requested;
+	struct tty_struct *tty = tty_port_tty_get(&tup->uport.state->port);
+	struct tty_port *port = &u->state->port;
+	unsigned long flags;
+
+	async_tx_ack(tup->rx_dma_desc);
+	spin_lock_irqsave(&u->lock, flags);
+
+	/* Deactivate flow control to stop sender */
+	if (tup->rts_active)
+		set_rts(tup, false);
+
+	/* If we are here, DMA is stopped */
+	if (count)
+		tegra_uart_copy_rx_to_tty(tup, port, count);
+
+	tegra_uart_handle_rx_pio(tup, port);
+	if (tty) {
+		tty_flip_buffer_push(port);
+		tty_kref_put(tty);
+	}
+	tegra_uart_start_rx_dma(tup);
+
+	/* Activate flow control to start transfer */
+	if (tup->rts_active)
+		set_rts(tup, true);
+
+	spin_unlock_irqrestore(&u->lock, flags);
+}
+
+static void tegra_uart_handle_rx_dma(struct tegra_uart_port *tup)
+{
+	struct dma_tx_state state;
+	struct tty_struct *tty = tty_port_tty_get(&tup->uport.state->port);
+	struct tty_port *port = &tup->uport.state->port;
+	int count;
+
+	/* Deactivate flow control to stop sender */
+	if (tup->rts_active)
+		set_rts(tup, false);
+
+	dmaengine_terminate_all(tup->rx_dma_chan);
+	dmaengine_tx_status(tup->rx_dma_chan,  tup->rx_cookie, &state);
+	count = tup->rx_bytes_requested - state.residue;
+
+	/* If we are here, DMA is stopped */
+	if (count)
+		tegra_uart_copy_rx_to_tty(tup, port, count);
+
+	tegra_uart_handle_rx_pio(tup, port);
+	if (tty) {
+		tty_flip_buffer_push(port);
+		tty_kref_put(tty);
+	}
+	tegra_uart_start_rx_dma(tup);
+
+	if (tup->rts_active)
+		set_rts(tup, true);
+}
+
+static int tegra_uart_start_rx_dma(struct tegra_uart_port *tup)
+{
+	unsigned int count = TEGRA_UART_RX_DMA_BUFFER_SIZE;
+
+	tup->rx_dma_desc = dmaengine_prep_slave_single(tup->rx_dma_chan,
+				tup->rx_dma_buf_phys, count, DMA_DEV_TO_MEM,
+				DMA_PREP_INTERRUPT);
+	if (!tup->rx_dma_desc) {
+		dev_err(tup->uport.dev, "Not able to get desc for Rx\n");
+		return -EIO;
+	}
+
+	tup->rx_dma_desc->callback = tegra_uart_rx_dma_complete;
+	tup->rx_dma_desc->callback_param = tup;
+	dma_sync_single_for_device(tup->uport.dev, tup->rx_dma_buf_phys,
+				count, DMA_TO_DEVICE);
+	tup->rx_bytes_requested = count;
+	tup->rx_cookie = dmaengine_submit(tup->rx_dma_desc);
+	dma_async_issue_pending(tup->rx_dma_chan);
+	return 0;
+}
+
+static void tegra_uart_handle_modem_signal_change(struct uart_port *u)
+{
+	struct tegra_uart_port *tup = to_tegra_uport(u);
+	unsigned long msr;
+
+	msr = tegra_uart_read(tup, UART_MSR);
+	if (!(msr & UART_MSR_ANY_DELTA))
+		return;
+
+	if (msr & UART_MSR_TERI)
+		tup->uport.icount.rng++;
+	if (msr & UART_MSR_DDSR)
+		tup->uport.icount.dsr++;
+	/* We may only get DDCD when HW init and reset */
+	if (msr & UART_MSR_DDCD)
+		uart_handle_dcd_change(&tup->uport, msr & UART_MSR_DCD);
+	/* Will start/stop_tx accordingly */
+	if (msr & UART_MSR_DCTS)
+		uart_handle_cts_change(&tup->uport, msr & UART_MSR_CTS);
+	return;
+}
+
+static irqreturn_t tegra_uart_isr(int irq, void *data)
+{
+	struct tegra_uart_port *tup = data;
+	struct uart_port *u = &tup->uport;
+	unsigned long iir;
+	unsigned long ier;
+	bool is_rx_int = false;
+	unsigned long flags;
+
+	spin_lock_irqsave(&u->lock, flags);
+	while (1) {
+		iir = tegra_uart_read(tup, UART_IIR);
+		if (iir & UART_IIR_NO_INT) {
+			if (is_rx_int) {
+				tegra_uart_handle_rx_dma(tup);
+				if (tup->rx_in_progress) {
+					ier = tup->ier_shadow;
+					ier |= (UART_IER_RLSI | UART_IER_RTOIE |
+						TEGRA_UART_IER_EORD);
+					tup->ier_shadow = ier;
+					tegra_uart_write(tup, ier, UART_IER);
+				}
+			}
+			spin_unlock_irqrestore(&u->lock, flags);
+			return IRQ_HANDLED;
+		}
+
+		switch ((iir >> 1) & 0x7) {
+		case 0: /* Modem signal change interrupt */
+			tegra_uart_handle_modem_signal_change(u);
+			break;
+
+		case 1: /* Transmit interrupt only triggered when using PIO */
+			tup->ier_shadow &= ~UART_IER_THRI;
+			tegra_uart_write(tup, tup->ier_shadow, UART_IER);
+			tegra_uart_handle_tx_pio(tup);
+			break;
+
+		case 4: /* End of data */
+		case 6: /* Rx timeout */
+		case 2: /* Receive */
+			if (!is_rx_int) {
+				is_rx_int = true;
+				/* Disable Rx interrupts */
+				ier = tup->ier_shadow;
+				ier |= UART_IER_RDI;
+				tegra_uart_write(tup, ier, UART_IER);
+				ier &= ~(UART_IER_RDI | UART_IER_RLSI |
+					UART_IER_RTOIE | TEGRA_UART_IER_EORD);
+				tup->ier_shadow = ier;
+				tegra_uart_write(tup, ier, UART_IER);
+			}
+			break;
+
+		case 3: /* Receive error */
+			tegra_uart_decode_rx_error(tup,
+					tegra_uart_read(tup, UART_LSR));
+			break;
+
+		case 5: /* break nothing to handle */
+		case 7: /* break nothing to handle */
+			break;
+		}
+	}
+}
+
+static void tegra_uart_stop_rx(struct uart_port *u)
+{
+	struct tegra_uart_port *tup = to_tegra_uport(u);
+	struct tty_struct *tty = tty_port_tty_get(&tup->uport.state->port);
+	struct tty_port *port = &u->state->port;
+	struct dma_tx_state state;
+	unsigned long ier;
+	int count;
+
+	if (tup->rts_active)
+		set_rts(tup, false);
+
+	if (!tup->rx_in_progress)
+		return;
+
+	tegra_uart_wait_sym_time(tup, 1); /* wait a character interval */
+
+	ier = tup->ier_shadow;
+	ier &= ~(UART_IER_RDI | UART_IER_RLSI | UART_IER_RTOIE |
+					TEGRA_UART_IER_EORD);
+	tup->ier_shadow = ier;
+	tegra_uart_write(tup, ier, UART_IER);
+	tup->rx_in_progress = 0;
+	if (tup->rx_dma_chan) {
+		dmaengine_terminate_all(tup->rx_dma_chan);
+		dmaengine_tx_status(tup->rx_dma_chan, tup->rx_cookie, &state);
+		async_tx_ack(tup->rx_dma_desc);
+		count = tup->rx_bytes_requested - state.residue;
+		tegra_uart_copy_rx_to_tty(tup, port, count);
+		tegra_uart_handle_rx_pio(tup, port);
+	} else {
+		tegra_uart_handle_rx_pio(tup, port);
+	}
+	if (tty) {
+		tty_flip_buffer_push(port);
+		tty_kref_put(tty);
+	}
+	return;
+}
+
+static void tegra_uart_hw_deinit(struct tegra_uart_port *tup)
+{
+	unsigned long flags;
+	unsigned long char_time = DIV_ROUND_UP(10000000, tup->current_baud);
+	unsigned long fifo_empty_time = tup->uport.fifosize * char_time;
+	unsigned long wait_time;
+	unsigned long lsr;
+	unsigned long msr;
+	unsigned long mcr;
+
+	/* Disable interrupts */
+	tegra_uart_write(tup, 0, UART_IER);
+
+	lsr = tegra_uart_read(tup, UART_LSR);
+	if ((lsr & UART_LSR_TEMT) != UART_LSR_TEMT) {
+		msr = tegra_uart_read(tup, UART_MSR);
+		mcr = tegra_uart_read(tup, UART_MCR);
+		if ((mcr & TEGRA_UART_MCR_CTS_EN) && (msr & UART_MSR_CTS))
+			dev_err(tup->uport.dev,
+				"Tx Fifo not empty, CTS disabled, waiting\n");
+
+		/* Wait for Tx fifo to be empty */
+		while ((lsr & UART_LSR_TEMT) != UART_LSR_TEMT) {
+			wait_time = min(fifo_empty_time, 100lu);
+			udelay(wait_time);
+			fifo_empty_time -= wait_time;
+			if (!fifo_empty_time) {
+				msr = tegra_uart_read(tup, UART_MSR);
+				mcr = tegra_uart_read(tup, UART_MCR);
+				if ((mcr & TEGRA_UART_MCR_CTS_EN) &&
+					(msr & UART_MSR_CTS))
+					dev_err(tup->uport.dev,
+						"Slave not ready\n");
+				break;
+			}
+			lsr = tegra_uart_read(tup, UART_LSR);
+		}
+	}
+
+	spin_lock_irqsave(&tup->uport.lock, flags);
+	/* Reset the Rx and Tx FIFOs */
+	tegra_uart_fifo_reset(tup, UART_FCR_CLEAR_XMIT | UART_FCR_CLEAR_RCVR);
+	tup->current_baud = 0;
+	spin_unlock_irqrestore(&tup->uport.lock, flags);
+
+	clk_disable_unprepare(tup->uart_clk);
+}
+
+static int tegra_uart_hw_init(struct tegra_uart_port *tup)
+{
+	int ret;
+
+	tup->fcr_shadow = 0;
+	tup->mcr_shadow = 0;
+	tup->lcr_shadow = 0;
+	tup->ier_shadow = 0;
+	tup->current_baud = 0;
+
+	clk_prepare_enable(tup->uart_clk);
+
+	/* Reset the UART controller to clear all previous status.*/
+	tegra_periph_reset_assert(tup->uart_clk);
+	udelay(10);
+	tegra_periph_reset_deassert(tup->uart_clk);
+
+	tup->rx_in_progress = 0;
+	tup->tx_in_progress = 0;
+
+	/*
+	 * Set the trigger level
+	 *
+	 * For PIO mode:
+	 *
+	 * For receive, this will interrupt the CPU after that many number of
+	 * bytes are received, for the remaining bytes the receive timeout
+	 * interrupt is received. Rx high watermark is set to 4.
+	 *
+	 * For transmit, if the trasnmit interrupt is enabled, this will
+	 * interrupt the CPU when the number of entries in the FIFO reaches the
+	 * low watermark. Tx low watermark is set to 16 bytes.
+	 *
+	 * For DMA mode:
+	 *
+	 * Set the Tx trigger to 16. This should match the DMA burst size that
+	 * programmed in the DMA registers.
+	 */
+	tup->fcr_shadow = UART_FCR_ENABLE_FIFO;
+	tup->fcr_shadow |= UART_FCR_R_TRIG_01;
+	tup->fcr_shadow |= TEGRA_UART_TX_TRIG_16B;
+	tegra_uart_write(tup, tup->fcr_shadow, UART_FCR);
+
+	/*
+	 * Initialize the UART with default configuration
+	 * (115200, N, 8, 1) so that the receive DMA buffer may be
+	 * enqueued
+	 */
+	tup->lcr_shadow = TEGRA_UART_DEFAULT_LSR;
+	tegra_set_baudrate(tup, TEGRA_UART_DEFAULT_BAUD);
+	tup->fcr_shadow |= UART_FCR_DMA_SELECT;
+	tegra_uart_write(tup, tup->fcr_shadow, UART_FCR);
+
+	ret = tegra_uart_start_rx_dma(tup);
+	if (ret < 0) {
+		dev_err(tup->uport.dev, "Not able to start Rx DMA\n");
+		return ret;
+	}
+	tup->rx_in_progress = 1;
+
+	/*
+	 * Enable IE_RXS for the receive status interrupts like line errros.
+	 * Enable IE_RX_TIMEOUT to get the bytes which cannot be DMA'd.
+	 *
+	 * If using DMA mode, enable EORD instead of receive interrupt which
+	 * will interrupt after the UART is done with the receive instead of
+	 * the interrupt when the FIFO "threshold" is reached.
+	 *
+	 * EORD is different interrupt than RX_TIMEOUT - RX_TIMEOUT occurs when
+	 * the DATA is sitting in the FIFO and couldn't be transferred to the
+	 * DMA as the DMA size alignment(4 bytes) is not met. EORD will be
+	 * triggered when there is a pause of the incomming data stream for 4
+	 * characters long.
+	 *
+	 * For pauses in the data which is not aligned to 4 bytes, we get
+	 * both the EORD as well as RX_TIMEOUT - SW sees RX_TIMEOUT first
+	 * then the EORD.
+	 */
+	tup->ier_shadow = UART_IER_RLSI | UART_IER_RTOIE | TEGRA_UART_IER_EORD;
+	tegra_uart_write(tup, tup->ier_shadow, UART_IER);
+	return 0;
+}
+
+static int tegra_uart_dma_channel_allocate(struct tegra_uart_port *tup,
+			bool dma_to_memory)
+{
+	struct dma_chan *dma_chan;
+	unsigned char *dma_buf;
+	dma_addr_t dma_phys;
+	int ret;
+	struct dma_slave_config dma_sconfig;
+	dma_cap_mask_t mask;
+
+	dma_cap_zero(mask);
+	dma_cap_set(DMA_SLAVE, mask);
+	dma_chan = dma_request_channel(mask, NULL, NULL);
+	if (!dma_chan) {
+		dev_err(tup->uport.dev,
+			"Dma channel is not available, will try later\n");
+		return -EPROBE_DEFER;
+	}
+
+	if (dma_to_memory) {
+		dma_buf = dma_alloc_coherent(tup->uport.dev,
+				TEGRA_UART_RX_DMA_BUFFER_SIZE,
+				 &dma_phys, GFP_KERNEL);
+		if (!dma_buf) {
+			dev_err(tup->uport.dev,
+				"Not able to allocate the dma buffer\n");
+			dma_release_channel(dma_chan);
+			return -ENOMEM;
+		}
+	} else {
+		dma_phys = dma_map_single(tup->uport.dev,
+			tup->uport.state->xmit.buf, UART_XMIT_SIZE,
+			DMA_TO_DEVICE);
+		dma_buf = tup->uport.state->xmit.buf;
+	}
+
+	dma_sconfig.slave_id = tup->dma_req_sel;
+	if (dma_to_memory) {
+		dma_sconfig.src_addr = tup->uport.mapbase;
+		dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+		dma_sconfig.src_maxburst = 4;
+	} else {
+		dma_sconfig.dst_addr = tup->uport.mapbase;
+		dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+		dma_sconfig.dst_maxburst = 16;
+	}
+
+	ret = dmaengine_slave_config(dma_chan, &dma_sconfig);
+	if (ret < 0) {
+		dev_err(tup->uport.dev,
+			"Dma slave config failed, err = %d\n", ret);
+		goto scrub;
+	}
+
+	if (dma_to_memory) {
+		tup->rx_dma_chan = dma_chan;
+		tup->rx_dma_buf_virt = dma_buf;
+		tup->rx_dma_buf_phys = dma_phys;
+	} else {
+		tup->tx_dma_chan = dma_chan;
+		tup->tx_dma_buf_virt = dma_buf;
+		tup->tx_dma_buf_phys = dma_phys;
+	}
+	return 0;
+
+scrub:
+	dma_release_channel(dma_chan);
+	return ret;
+}
+
+static void tegra_uart_dma_channel_free(struct tegra_uart_port *tup,
+		bool dma_to_memory)
+{
+	struct dma_chan *dma_chan;
+
+	if (dma_to_memory) {
+		dma_free_coherent(tup->uport.dev, TEGRA_UART_RX_DMA_BUFFER_SIZE,
+				tup->rx_dma_buf_virt, tup->rx_dma_buf_phys);
+		dma_chan = tup->rx_dma_chan;
+		tup->rx_dma_chan = NULL;
+		tup->rx_dma_buf_phys = 0;
+		tup->rx_dma_buf_virt = NULL;
+	} else {
+		dma_unmap_single(tup->uport.dev, tup->tx_dma_buf_phys,
+			UART_XMIT_SIZE, DMA_TO_DEVICE);
+		dma_chan = tup->tx_dma_chan;
+		tup->tx_dma_chan = NULL;
+		tup->tx_dma_buf_phys = 0;
+		tup->tx_dma_buf_virt = NULL;
+	}
+	dma_release_channel(dma_chan);
+}
+
+static int tegra_uart_startup(struct uart_port *u)
+{
+	struct tegra_uart_port *tup = to_tegra_uport(u);
+	int ret;
+
+	ret = tegra_uart_dma_channel_allocate(tup, false);
+	if (ret < 0) {
+		dev_err(u->dev, "Tx Dma allocation failed, err = %d\n", ret);
+		return ret;
+	}
+
+	ret = tegra_uart_dma_channel_allocate(tup, true);
+	if (ret < 0) {
+		dev_err(u->dev, "Rx Dma allocation failed, err = %d\n", ret);
+		goto fail_rx_dma;
+	}
+
+	ret = tegra_uart_hw_init(tup);
+	if (ret < 0) {
+		dev_err(u->dev, "Uart HW init failed, err = %d\n", ret);
+		goto fail_hw_init;
+	}
+
+	ret = request_irq(u->irq, tegra_uart_isr, IRQF_DISABLED,
+				dev_name(u->dev), tup);
+	if (ret < 0) {
+		dev_err(u->dev, "Failed to register ISR for IRQ %d\n", u->irq);
+		goto fail_hw_init;
+	}
+	return 0;
+
+fail_hw_init:
+	tegra_uart_dma_channel_free(tup, true);
+fail_rx_dma:
+	tegra_uart_dma_channel_free(tup, false);
+	return ret;
+}
+
+static void tegra_uart_shutdown(struct uart_port *u)
+{
+	struct tegra_uart_port *tup = to_tegra_uport(u);
+
+	tegra_uart_hw_deinit(tup);
+
+	tup->rx_in_progress = 0;
+	tup->tx_in_progress = 0;
+
+	tegra_uart_dma_channel_free(tup, true);
+	tegra_uart_dma_channel_free(tup, false);
+	free_irq(u->irq, tup);
+}
+
+static void tegra_uart_enable_ms(struct uart_port *u)
+{
+	struct tegra_uart_port *tup = to_tegra_uport(u);
+
+	if (tup->enable_modem_interrupt) {
+		tup->ier_shadow |= UART_IER_MSI;
+		tegra_uart_write(tup, tup->ier_shadow, UART_IER);
+	}
+}
+
+static void tegra_uart_set_termios(struct uart_port *u,
+		struct ktermios *termios, struct ktermios *oldtermios)
+{
+	struct tegra_uart_port *tup = to_tegra_uport(u);
+	unsigned int baud;
+	unsigned long flags;
+	unsigned int lcr;
+	int symb_bit = 1;
+	struct clk *parent_clk = clk_get_parent(tup->uart_clk);
+	unsigned long parent_clk_rate = clk_get_rate(parent_clk);
+	int max_divider = (tup->cdata->support_clk_src_div) ? 0x7FFF : 0xFFFF;
+
+	max_divider *= 16;
+	spin_lock_irqsave(&u->lock, flags);
+
+	/* Changing configuration, it is safe to stop any rx now */
+	if (tup->rts_active)
+		set_rts(tup, false);
+
+	/* Clear all interrupts as configuration is going to be change */
+	tegra_uart_write(tup, tup->ier_shadow | UART_IER_RDI, UART_IER);
+	tegra_uart_read(tup, UART_IER);
+	tegra_uart_write(tup, 0, UART_IER);
+	tegra_uart_read(tup, UART_IER);
+
+	/* Parity */
+	lcr = tup->lcr_shadow;
+	lcr &= ~UART_LCR_PARITY;
+
+	/* CMSPAR isn't supported by this driver */
+	termios->c_cflag &= ~CMSPAR;
+
+	if ((termios->c_cflag & PARENB) == PARENB) {
+		symb_bit++;
+		if (termios->c_cflag & PARODD) {
+			lcr |= UART_LCR_PARITY;
+			lcr &= ~UART_LCR_EPAR;
+			lcr &= ~UART_LCR_SPAR;
+		} else {
+			lcr |= UART_LCR_PARITY;
+			lcr |= UART_LCR_EPAR;
+			lcr &= ~UART_LCR_SPAR;
+		}
+	}
+
+	lcr &= ~UART_LCR_WLEN8;
+	switch (termios->c_cflag & CSIZE) {
+	case CS5:
+		lcr |= UART_LCR_WLEN5;
+		symb_bit += 5;
+		break;
+	case CS6:
+		lcr |= UART_LCR_WLEN6;
+		symb_bit += 6;
+		break;
+	case CS7:
+		lcr |= UART_LCR_WLEN7;
+		symb_bit += 7;
+		break;
+	default:
+		lcr |= UART_LCR_WLEN8;
+		symb_bit += 8;
+		break;
+	}
+
+	/* Stop bits */
+	if (termios->c_cflag & CSTOPB) {
+		lcr |= UART_LCR_STOP;
+		symb_bit += 2;
+	} else {
+		lcr &= ~UART_LCR_STOP;
+		symb_bit++;
+	}
+
+	tegra_uart_write(tup, lcr, UART_LCR);
+	tup->lcr_shadow = lcr;
+	tup->symb_bit = symb_bit;
+
+	/* Baud rate. */
+	baud = uart_get_baud_rate(u, termios, oldtermios,
+			parent_clk_rate/max_divider,
+			parent_clk_rate/16);
+	spin_unlock_irqrestore(&u->lock, flags);
+	tegra_set_baudrate(tup, baud);
+	if (tty_termios_baud_rate(termios))
+		tty_termios_encode_baud_rate(termios, baud, baud);
+	spin_lock_irqsave(&u->lock, flags);
+
+	/* Flow control */
+	if (termios->c_cflag & CRTSCTS)	{
+		tup->mcr_shadow |= TEGRA_UART_MCR_CTS_EN;
+		tup->mcr_shadow &= ~TEGRA_UART_MCR_RTS_EN;
+		tegra_uart_write(tup, tup->mcr_shadow, UART_MCR);
+		/* if top layer has asked to set rts active then do so here */
+		if (tup->rts_active)
+			set_rts(tup, true);
+	} else {
+		tup->mcr_shadow &= ~TEGRA_UART_MCR_CTS_EN;
+		tup->mcr_shadow &= ~TEGRA_UART_MCR_RTS_EN;
+		tegra_uart_write(tup, tup->mcr_shadow, UART_MCR);
+	}
+
+	/* update the port timeout based on new settings */
+	uart_update_timeout(u, termios->c_cflag, baud);
+
+	/* Make sure all write has completed */
+	tegra_uart_read(tup, UART_IER);
+
+	/* Reenable interrupt */
+	tegra_uart_write(tup, tup->ier_shadow, UART_IER);
+	tegra_uart_read(tup, UART_IER);
+
+	spin_unlock_irqrestore(&u->lock, flags);
+	return;
+}
+
+/*
+ * Flush any TX data submitted for DMA and PIO. Called when the
+ * TX circular buffer is reset.
+ */
+static void tegra_uart_flush_buffer(struct uart_port *u)
+{
+	struct tegra_uart_port *tup = to_tegra_uport(u);
+
+	tup->tx_bytes = 0;
+	if (tup->tx_dma_chan)
+		dmaengine_terminate_all(tup->tx_dma_chan);
+	return;
+}
+
+static const char *tegra_uart_type(struct uart_port *u)
+{
+	return TEGRA_UART_TYPE;
+}
+
+static struct uart_ops tegra_uart_ops = {
+	.tx_empty	= tegra_uart_tx_empty,
+	.set_mctrl	= tegra_uart_set_mctrl,
+	.get_mctrl	= tegra_uart_get_mctrl,
+	.stop_tx	= tegra_uart_stop_tx,
+	.start_tx	= tegra_uart_start_tx,
+	.stop_rx	= tegra_uart_stop_rx,
+	.flush_buffer	= tegra_uart_flush_buffer,
+	.enable_ms	= tegra_uart_enable_ms,
+	.break_ctl	= tegra_uart_break_ctl,
+	.startup	= tegra_uart_startup,
+	.shutdown	= tegra_uart_shutdown,
+	.set_termios	= tegra_uart_set_termios,
+	.type		= tegra_uart_type,
+	.request_port	= tegra_uart_request_port,
+	.release_port	= tegra_uart_release_port,
+};
+
+static struct uart_driver tegra_uart_driver = {
+	.owner		= THIS_MODULE,
+	.driver_name	= "tegra_hsuart",
+	.dev_name	= "ttyTHS",
+	.cons		= 0,
+	.nr		= TEGRA_UART_MAXIMUM,
+};
+
+static int tegra_uart_parse_dt(struct platform_device *pdev,
+	struct tegra_uart_port *tup)
+{
+	struct device_node *np = pdev->dev.of_node;
+	u32 of_dma[2];
+	int port;
+
+	if (of_property_read_u32_array(np, "nvidia,dma-request-selector",
+				of_dma, 2) >= 0) {
+		tup->dma_req_sel = of_dma[1];
+	} else {
+		dev_err(&pdev->dev, "missing dma requestor in device tree\n");
+		return -EINVAL;
+	}
+
+	port = of_alias_get_id(np, "serial");
+	if (port < 0) {
+		dev_err(&pdev->dev, "failed to get alias id, errno %d\n", port);
+		return port;
+	}
+	tup->uport.line = port;
+
+	tup->enable_modem_interrupt = of_property_read_bool(np,
+					"nvidia,enable-modem-interrupt");
+	return 0;
+}
+
+struct tegra_uart_chip_data tegra20_uart_chip_data = {
+	.tx_fifo_full_status		= false,
+	.allow_txfifo_reset_fifo_mode	= true,
+	.support_clk_src_div		= false,
+};
+
+struct tegra_uart_chip_data tegra30_uart_chip_data = {
+	.tx_fifo_full_status		= true,
+	.allow_txfifo_reset_fifo_mode	= false,
+	.support_clk_src_div		= true,
+};
+
+static struct of_device_id tegra_uart_of_match[] = {
+	{
+		.compatible	= "nvidia,tegra30-hsuart",
+		.data		= &tegra30_uart_chip_data,
+	}, {
+		.compatible	= "nvidia,tegra20-hsuart",
+		.data		= &tegra20_uart_chip_data,
+	}, {
+	},
+};
+MODULE_DEVICE_TABLE(of, tegra_uart_of_match);
+
+static int tegra_uart_probe(struct platform_device *pdev)
+{
+	struct tegra_uart_port *tup;
+	struct uart_port *u;
+	struct resource *resource;
+	int ret;
+	const struct tegra_uart_chip_data *cdata;
+	const struct of_device_id *match;
+
+	match = of_match_device(tegra_uart_of_match, &pdev->dev);
+	if (!match) {
+		dev_err(&pdev->dev, "Error: No device match found\n");
+		return -ENODEV;
+	}
+	cdata = match->data;
+
+	tup = devm_kzalloc(&pdev->dev, sizeof(*tup), GFP_KERNEL);
+	if (!tup) {
+		dev_err(&pdev->dev, "Failed to allocate memory for tup\n");
+		return -ENOMEM;
+	}
+
+	ret = tegra_uart_parse_dt(pdev, tup);
+	if (ret < 0)
+		return ret;
+
+	u = &tup->uport;
+	u->dev = &pdev->dev;
+	u->ops = &tegra_uart_ops;
+	u->type = PORT_TEGRA;
+	u->fifosize = 32;
+	tup->cdata = cdata;
+
+	platform_set_drvdata(pdev, tup);
+	resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!resource) {
+		dev_err(&pdev->dev, "No IO memory resource\n");
+		return -ENODEV;
+	}
+
+	u->mapbase = resource->start;
+	u->membase = devm_request_and_ioremap(&pdev->dev, resource);
+	if (!u->membase) {
+		dev_err(&pdev->dev, "memregion/iomap address req failed\n");
+		return -EADDRNOTAVAIL;
+	}
+
+	tup->uart_clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(tup->uart_clk)) {
+		dev_err(&pdev->dev, "Couldn't get the clock\n");
+		return PTR_ERR(tup->uart_clk);
+	}
+
+	u->iotype = UPIO_MEM32;
+	u->irq = platform_get_irq(pdev, 0);
+	u->regshift = 2;
+	ret = uart_add_one_port(&tegra_uart_driver, u);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Failed to add uart port, err %d\n", ret);
+		return ret;
+	}
+	return ret;
+}
+
+static int tegra_uart_remove(struct platform_device *pdev)
+{
+	struct tegra_uart_port *tup = platform_get_drvdata(pdev);
+	struct uart_port *u = &tup->uport;
+
+	uart_remove_one_port(&tegra_uart_driver, u);
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int tegra_uart_suspend(struct device *dev)
+{
+	struct tegra_uart_port *tup = dev_get_drvdata(dev);
+	struct uart_port *u = &tup->uport;
+
+	return uart_suspend_port(&tegra_uart_driver, u);
+}
+
+static int tegra_uart_resume(struct device *dev)
+{
+	struct tegra_uart_port *tup = dev_get_drvdata(dev);
+	struct uart_port *u = &tup->uport;
+
+	return uart_resume_port(&tegra_uart_driver, u);
+}
+#endif
+
+static const struct dev_pm_ops tegra_uart_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(tegra_uart_suspend, tegra_uart_resume)
+};
+
+static struct platform_driver tegra_uart_platform_driver = {
+	.probe		= tegra_uart_probe,
+	.remove		= tegra_uart_remove,
+	.driver		= {
+		.name	= "serial-tegra",
+		.of_match_table = tegra_uart_of_match,
+		.pm	= &tegra_uart_pm_ops,
+	},
+};
+
+static int __init tegra_uart_init(void)
+{
+	int ret;
+
+	ret = uart_register_driver(&tegra_uart_driver);
+	if (ret < 0) {
+		pr_err("Could not register %s driver\n",
+			tegra_uart_driver.driver_name);
+		return ret;
+	}
+
+	ret = platform_driver_register(&tegra_uart_platform_driver);
+	if (ret < 0) {
+		pr_err("Uart platfrom driver register failed, e = %d\n", ret);
+		uart_unregister_driver(&tegra_uart_driver);
+		return ret;
+	}
+	return 0;
+}
+
+static void __exit tegra_uart_exit(void)
+{
+	pr_info("Unloading tegra uart driver\n");
+	platform_driver_unregister(&tegra_uart_platform_driver);
+	uart_unregister_driver(&tegra_uart_driver);
+}
+
+module_init(tegra_uart_init);
+module_exit(tegra_uart_exit);
+
+MODULE_ALIAS("platform:serial-tegra");
+MODULE_DESCRIPTION("High speed UART driver for tegra chipset");
+MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 2c7230aaefd..a400002dfa8 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -59,7 +59,8 @@ static struct lock_class_key port_lock_key;
 static void uart_change_speed(struct tty_struct *tty, struct uart_state *state,
 					struct ktermios *old_termios);
 static void uart_wait_until_sent(struct tty_struct *tty, int timeout);
-static void uart_change_pm(struct uart_state *state, int pm_state);
+static void uart_change_pm(struct uart_state *state,
+			   enum uart_pm_state pm_state);
 
 static void uart_port_shutdown(struct tty_port *port);
 
@@ -866,9 +867,7 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port,
 	port->closing_wait    = closing_wait;
 	if (new_info->xmit_fifo_size)
 		uport->fifosize = new_info->xmit_fifo_size;
-	if (port->tty)
-		port->tty->low_latency =
-			(uport->flags & UPF_LOW_LATENCY) ? 1 : 0;
+	port->low_latency = (uport->flags & UPF_LOW_LATENCY) ? 1 : 0;
 
  check_and_exit:
 	retval = 0;
@@ -1308,9 +1307,10 @@ static void uart_set_termios(struct tty_struct *tty,
 }
 
 /*
- * In 2.4.5, calls to this will be serialized via the BKL in
- *  linux/drivers/char/tty_io.c:tty_release()
- *  linux/drivers/char/tty_io.c:do_tty_handup()
+ * Calls to uart_close() are serialised via the tty_lock in
+ *   drivers/tty/tty_io.c:tty_release()
+ *   drivers/tty/tty_io.c:do_tty_hangup()
+ * This runs from a workqueue and can sleep for a _short_ time only.
  */
 static void uart_close(struct tty_struct *tty, struct file *filp)
 {
@@ -1365,7 +1365,7 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
 		spin_lock_irqsave(&port->lock, flags);
 	} else if (!uart_console(uport)) {
 		spin_unlock_irqrestore(&port->lock, flags);
-		uart_change_pm(state, 3);
+		uart_change_pm(state, UART_PM_STATE_OFF);
 		spin_lock_irqsave(&port->lock, flags);
 	}
 
@@ -1437,10 +1437,9 @@ static void uart_wait_until_sent(struct tty_struct *tty, int timeout)
 }
 
 /*
- * This is called with the BKL held in
- *  linux/drivers/char/tty_io.c:do_tty_hangup()
- * We're called from the eventd thread, so we can sleep for
- * a _short_ time only.
+ * Calls to uart_hangup() are serialised by the tty_lock in
+ *   drivers/tty/tty_io.c:do_tty_hangup()
+ * This runs from a workqueue and can sleep for a _short_ time only.
  */
 static void uart_hangup(struct tty_struct *tty)
 {
@@ -1521,8 +1520,8 @@ static void uart_dtr_rts(struct tty_port *port, int onoff)
 }
 
 /*
- * calls to uart_open are serialised by the BKL in
- *   fs/char_dev.c:chrdev_open()
+ * Calls to uart_open are serialised by the tty_lock in
+ *   drivers/tty/tty_io.c:tty_open()
  * Note that if this fails, then uart_close() _will_ be called.
  *
  * In time, we want to scrap the "opening nonpresent ports"
@@ -1564,7 +1563,8 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
 	 */
 	tty->driver_data = state;
 	state->uart_port->state = state;
-	tty->low_latency = (state->uart_port->flags & UPF_LOW_LATENCY) ? 1 : 0;
+	state->port.low_latency =
+		(state->uart_port->flags & UPF_LOW_LATENCY) ? 1 : 0;
 	tty_port_tty_set(port, tty);
 
 	/*
@@ -1579,7 +1579,7 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
 	 * Make sure the device is in D0 state.
 	 */
 	if (port->count == 1)
-		uart_change_pm(state, 0);
+		uart_change_pm(state, UART_PM_STATE_ON);
 
 	/*
 	 * Start up the serial port.
@@ -1620,7 +1620,7 @@ static void uart_line_info(struct seq_file *m, struct uart_driver *drv, int i)
 {
 	struct uart_state *state = drv->state + i;
 	struct tty_port *port = &state->port;
-	int pm_state;
+	enum uart_pm_state pm_state;
 	struct uart_port *uport = state->uart_port;
 	char stat_buf[32];
 	unsigned int status;
@@ -1645,12 +1645,12 @@ static void uart_line_info(struct seq_file *m, struct uart_driver *drv, int i)
 	if (capable(CAP_SYS_ADMIN)) {
 		mutex_lock(&port->mutex);
 		pm_state = state->pm_state;
-		if (pm_state)
-			uart_change_pm(state, 0);
+		if (pm_state != UART_PM_STATE_ON)
+			uart_change_pm(state, UART_PM_STATE_ON);
 		spin_lock_irq(&uport->lock);
 		status = uport->ops->get_mctrl(uport);
 		spin_unlock_irq(&uport->lock);
-		if (pm_state)
+		if (pm_state != UART_PM_STATE_ON)
 			uart_change_pm(state, pm_state);
 		mutex_unlock(&port->mutex);
 
@@ -1897,7 +1897,8 @@ EXPORT_SYMBOL_GPL(uart_set_options);
  *
  * Locking: port->mutex has to be held
  */
-static void uart_change_pm(struct uart_state *state, int pm_state)
+static void uart_change_pm(struct uart_state *state,
+			   enum uart_pm_state pm_state)
 {
 	struct uart_port *port = state->uart_port;
 
@@ -1982,7 +1983,7 @@ int uart_suspend_port(struct uart_driver *drv, struct uart_port *uport)
 		console_stop(uport->cons);
 
 	if (console_suspend_enabled || !uart_console(uport))
-		uart_change_pm(state, 3);
+		uart_change_pm(state, UART_PM_STATE_OFF);
 
 	mutex_unlock(&port->mutex);
 
@@ -2027,7 +2028,7 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *uport)
 			termios = port->tty->termios;
 
 		if (console_suspend_enabled)
-			uart_change_pm(state, 0);
+			uart_change_pm(state, UART_PM_STATE_ON);
 		uport->ops->set_termios(uport, &termios, NULL);
 		if (console_suspend_enabled)
 			console_start(uport->cons);
@@ -2037,7 +2038,7 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *uport)
 		const struct uart_ops *ops = uport->ops;
 		int ret;
 
-		uart_change_pm(state, 0);
+		uart_change_pm(state, UART_PM_STATE_ON);
 		spin_lock_irq(&uport->lock);
 		ops->set_mctrl(uport, 0);
 		spin_unlock_irq(&uport->lock);
@@ -2137,7 +2138,7 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state,
 		uart_report_port(drv, port);
 
 		/* Power up port for set_mctrl() */
-		uart_change_pm(state, 0);
+		uart_change_pm(state, UART_PM_STATE_ON);
 
 		/*
 		 * Ensure that the modem control lines are de-activated.
@@ -2161,7 +2162,7 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state,
 		 * console if we have one.
 		 */
 		if (!uart_console(port))
-			uart_change_pm(state, 3);
+			uart_change_pm(state, UART_PM_STATE_OFF);
 	}
 }
 
@@ -2588,7 +2589,7 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport)
 	}
 
 	state->uart_port = uport;
-	state->pm_state = -1;
+	state->pm_state = UART_PM_STATE_UNDEFINED;
 
 	uport->cons = drv->cons;
 	uport->state = state;
@@ -2642,6 +2643,7 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport)
 {
 	struct uart_state *state = drv->state + uport->line;
 	struct tty_port *port = &state->port;
+	int ret = 0;
 
 	BUG_ON(in_interrupt());
 
@@ -2656,6 +2658,11 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport)
 	 * succeeding while we shut down the port.
 	 */
 	mutex_lock(&port->mutex);
+	if (!state->uart_port) {
+		mutex_unlock(&port->mutex);
+		ret = -EINVAL;
+		goto out;
+	}
 	uport->flags |= UPF_DEAD;
 	mutex_unlock(&port->mutex);
 
@@ -2679,9 +2686,10 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport)
 	uport->type = PORT_UNKNOWN;
 
 	state->uart_port = NULL;
+out:
 	mutex_unlock(&port_mutex);
 
-	return 0;
+	return ret;
 }
 
 /*
@@ -2715,22 +2723,17 @@ EXPORT_SYMBOL(uart_match_port);
  */
 void uart_handle_dcd_change(struct uart_port *uport, unsigned int status)
 {
-	struct uart_state *state = uport->state;
-	struct tty_port *port = &state->port;
-	struct tty_ldisc *ld = NULL;
-	struct pps_event_time ts;
+	struct tty_port *port = &uport->state->port;
 	struct tty_struct *tty = port->tty;
+	struct tty_ldisc *ld = tty ? tty_ldisc_ref(tty) : NULL;
 
-	if (tty)
-	        ld = tty_ldisc_ref(tty);
-	if (ld && ld->ops->dcd_change)
-		pps_get_ts(&ts);
+	if (ld) {
+		if (ld->ops->dcd_change)
+			ld->ops->dcd_change(tty, status);
+		tty_ldisc_deref(ld);
+	}
 
 	uport->icount.dcd++;
-#ifdef CONFIG_HARD_PPS
-	if ((uport->flags & UPF_HARDPPS_CD) && status)
-		hardpps();
-#endif
 
 	if (port->flags & ASYNC_CHECK_CD) {
 		if (status)
@@ -2738,11 +2741,6 @@ void uart_handle_dcd_change(struct uart_port *uport, unsigned int status)
 		else if (tty)
 			tty_hangup(tty);
 	}
-
-	if (ld && ld->ops->dcd_change)
-		ld->ops->dcd_change(tty, status, &ts);
-	if (ld)
-		tty_ldisc_deref(ld);
 }
 EXPORT_SYMBOL_GPL(uart_handle_dcd_change);
 
@@ -2790,10 +2788,10 @@ EXPORT_SYMBOL_GPL(uart_handle_cts_change);
 void uart_insert_char(struct uart_port *port, unsigned int status,
 		 unsigned int overrun, unsigned int ch, unsigned int flag)
 {
-	struct tty_struct *tty = port->state->port.tty;
+	struct tty_port *tport = &port->state->port;
 
 	if ((status & port->ignore_status_mask & ~overrun) == 0)
-		if (tty_insert_flip_char(tty, ch, flag) == 0)
+		if (tty_insert_flip_char(tport, ch, flag) == 0)
 			++port->icount.buf_overrun;
 
 	/*
@@ -2801,7 +2799,7 @@ void uart_insert_char(struct uart_port *port, unsigned int status,
 	 * it doesn't affect the current character.
 	 */
 	if (status & ~port->ignore_status_mask & overrun)
-		if (tty_insert_flip_char(tty, 0, TTY_OVERRUN) == 0)
+		if (tty_insert_flip_char(tport, 0, TTY_OVERRUN) == 0)
 			++port->icount.buf_overrun;
 }
 EXPORT_SYMBOL_GPL(uart_insert_char);
diff --git a/drivers/tty/serial/serial_ks8695.c b/drivers/tty/serial/serial_ks8695.c
index 9bd004f9da8..e1caa99e3d3 100644
--- a/drivers/tty/serial/serial_ks8695.c
+++ b/drivers/tty/serial/serial_ks8695.c
@@ -153,7 +153,6 @@ static void ks8695uart_disable_ms(struct uart_port *port)
 static irqreturn_t ks8695uart_rx_chars(int irq, void *dev_id)
 {
 	struct uart_port *port = dev_id;
-	struct tty_struct *tty = port->state->port.tty;
 	unsigned int status, ch, lsr, flg, max_count = 256;
 
 	status = UART_GET_LSR(port);		/* clears pending LSR interrupts */
@@ -200,7 +199,7 @@ static irqreturn_t ks8695uart_rx_chars(int irq, void *dev_id)
 ignore_char:
 		status = UART_GET_LSR(port);
 	}
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&port->state->port);
 
 	return IRQ_HANDLED;
 }
diff --git a/drivers/tty/serial/serial_txx9.c b/drivers/tty/serial/serial_txx9.c
index b52b21aeb25..fe48a0c2b4c 100644
--- a/drivers/tty/serial/serial_txx9.c
+++ b/drivers/tty/serial/serial_txx9.c
@@ -277,7 +277,6 @@ static void serial_txx9_initialize(struct uart_port *port)
 static inline void
 receive_chars(struct uart_txx9_port *up, unsigned int *status)
 {
-	struct tty_struct *tty = up->port.state->port.tty;
 	unsigned char ch;
 	unsigned int disr = *status;
 	int max_count = 256;
@@ -346,7 +345,7 @@ receive_chars(struct uart_txx9_port *up, unsigned int *status)
 		disr = sio_in(up, TXX9_SIDISR);
 	} while (!(disr & TXX9_SIDISR_UVALID) && (max_count-- > 0));
 	spin_unlock(&up->port.lock);
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&up->port.state->port);
 	spin_lock(&up->port.lock);
 	*status = disr;
 }
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 61477567423..15641861994 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -596,7 +596,7 @@ static void sci_transmit_chars(struct uart_port *port)
 static void sci_receive_chars(struct uart_port *port)
 {
 	struct sci_port *sci_port = to_sci_port(port);
-	struct tty_struct *tty = port->state->port.tty;
+	struct tty_port *tport = &port->state->port;
 	int i, count, copied = 0;
 	unsigned short status;
 	unsigned char flag;
@@ -607,7 +607,7 @@ static void sci_receive_chars(struct uart_port *port)
 
 	while (1) {
 		/* Don't copy more bytes than there is room for in the buffer */
-		count = tty_buffer_request_room(tty, sci_rxfill(port));
+		count = tty_buffer_request_room(tport, sci_rxfill(port));
 
 		/* If for any reason we can't copy more data, we're done! */
 		if (count == 0)
@@ -619,7 +619,7 @@ static void sci_receive_chars(struct uart_port *port)
 			    sci_port->break_flag)
 				count = 0;
 			else
-				tty_insert_flip_char(tty, c, TTY_NORMAL);
+				tty_insert_flip_char(tport, c, TTY_NORMAL);
 		} else {
 			for (i = 0; i < count; i++) {
 				char c = serial_port_in(port, SCxRDR);
@@ -661,7 +661,7 @@ static void sci_receive_chars(struct uart_port *port)
 				} else
 					flag = TTY_NORMAL;
 
-				tty_insert_flip_char(tty, c, flag);
+				tty_insert_flip_char(tport, c, flag);
 			}
 		}
 
@@ -674,7 +674,7 @@ static void sci_receive_chars(struct uart_port *port)
 
 	if (copied) {
 		/* Tell the rest of the system the news. New characters! */
-		tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(tport);
 	} else {
 		serial_port_in(port, SCxSR); /* dummy read */
 		serial_port_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
@@ -720,7 +720,7 @@ static int sci_handle_errors(struct uart_port *port)
 {
 	int copied = 0;
 	unsigned short status = serial_port_in(port, SCxSR);
-	struct tty_struct *tty = port->state->port.tty;
+	struct tty_port *tport = &port->state->port;
 	struct sci_port *s = to_sci_port(port);
 
 	/*
@@ -731,7 +731,7 @@ static int sci_handle_errors(struct uart_port *port)
 			port->icount.overrun++;
 
 			/* overrun error */
-			if (tty_insert_flip_char(tty, 0, TTY_OVERRUN))
+			if (tty_insert_flip_char(tport, 0, TTY_OVERRUN))
 				copied++;
 
 			dev_notice(port->dev, "overrun error");
@@ -755,7 +755,7 @@ static int sci_handle_errors(struct uart_port *port)
 
 				dev_dbg(port->dev, "BREAK detected\n");
 
-				if (tty_insert_flip_char(tty, 0, TTY_BREAK))
+				if (tty_insert_flip_char(tport, 0, TTY_BREAK))
 					copied++;
 			}
 
@@ -763,7 +763,7 @@ static int sci_handle_errors(struct uart_port *port)
 			/* frame error */
 			port->icount.frame++;
 
-			if (tty_insert_flip_char(tty, 0, TTY_FRAME))
+			if (tty_insert_flip_char(tport, 0, TTY_FRAME))
 				copied++;
 
 			dev_notice(port->dev, "frame error\n");
@@ -774,21 +774,21 @@ static int sci_handle_errors(struct uart_port *port)
 		/* parity error */
 		port->icount.parity++;
 
-		if (tty_insert_flip_char(tty, 0, TTY_PARITY))
+		if (tty_insert_flip_char(tport, 0, TTY_PARITY))
 			copied++;
 
 		dev_notice(port->dev, "parity error");
 	}
 
 	if (copied)
-		tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(tport);
 
 	return copied;
 }
 
 static int sci_handle_fifo_overrun(struct uart_port *port)
 {
-	struct tty_struct *tty = port->state->port.tty;
+	struct tty_port *tport = &port->state->port;
 	struct sci_port *s = to_sci_port(port);
 	struct plat_sci_reg *reg;
 	int copied = 0;
@@ -802,8 +802,8 @@ static int sci_handle_fifo_overrun(struct uart_port *port)
 
 		port->icount.overrun++;
 
-		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
-		tty_flip_buffer_push(tty);
+		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
+		tty_flip_buffer_push(tport);
 
 		dev_notice(port->dev, "overrun error\n");
 		copied++;
@@ -816,7 +816,7 @@ static int sci_handle_breaks(struct uart_port *port)
 {
 	int copied = 0;
 	unsigned short status = serial_port_in(port, SCxSR);
-	struct tty_struct *tty = port->state->port.tty;
+	struct tty_port *tport = &port->state->port;
 	struct sci_port *s = to_sci_port(port);
 
 	if (uart_handle_break(port))
@@ -831,14 +831,14 @@ static int sci_handle_breaks(struct uart_port *port)
 		port->icount.brk++;
 
 		/* Notify of BREAK */
-		if (tty_insert_flip_char(tty, 0, TTY_BREAK))
+		if (tty_insert_flip_char(tport, 0, TTY_BREAK))
 			copied++;
 
 		dev_dbg(port->dev, "BREAK detected\n");
 	}
 
 	if (copied)
-		tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(tport);
 
 	copied += sci_handle_fifo_overrun(port);
 
@@ -1259,13 +1259,13 @@ static void sci_dma_tx_complete(void *arg)
 }
 
 /* Locking: called with port lock held */
-static int sci_dma_rx_push(struct sci_port *s, struct tty_struct *tty,
-			   size_t count)
+static int sci_dma_rx_push(struct sci_port *s, size_t count)
 {
 	struct uart_port *port = &s->port;
+	struct tty_port *tport = &port->state->port;
 	int i, active, room;
 
-	room = tty_buffer_request_room(tty, count);
+	room = tty_buffer_request_room(tport, count);
 
 	if (s->active_rx == s->cookie_rx[0]) {
 		active = 0;
@@ -1283,7 +1283,7 @@ static int sci_dma_rx_push(struct sci_port *s, struct tty_struct *tty,
 		return room;
 
 	for (i = 0; i < room; i++)
-		tty_insert_flip_char(tty, ((u8 *)sg_virt(&s->sg_rx[active]))[i],
+		tty_insert_flip_char(tport, ((u8 *)sg_virt(&s->sg_rx[active]))[i],
 				     TTY_NORMAL);
 
 	port->icount.rx += room;
@@ -1295,7 +1295,6 @@ static void sci_dma_rx_complete(void *arg)
 {
 	struct sci_port *s = arg;
 	struct uart_port *port = &s->port;
-	struct tty_struct *tty = port->state->port.tty;
 	unsigned long flags;
 	int count;
 
@@ -1303,14 +1302,14 @@ static void sci_dma_rx_complete(void *arg)
 
 	spin_lock_irqsave(&port->lock, flags);
 
-	count = sci_dma_rx_push(s, tty, s->buf_len_rx);
+	count = sci_dma_rx_push(s, s->buf_len_rx);
 
 	mod_timer(&s->rx_timer, jiffies + s->rx_timeout);
 
 	spin_unlock_irqrestore(&port->lock, flags);
 
 	if (count)
-		tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(&port->state->port);
 
 	schedule_work(&s->work_rx);
 }
@@ -1404,7 +1403,6 @@ static void work_fn_rx(struct work_struct *work)
 	if (dma_async_is_tx_complete(s->chan_rx, s->active_rx, NULL, NULL) !=
 	    DMA_SUCCESS) {
 		/* Handle incomplete DMA receive */
-		struct tty_struct *tty = port->state->port.tty;
 		struct dma_chan *chan = s->chan_rx;
 		struct shdma_desc *sh_desc = container_of(desc,
 					struct shdma_desc, async_tx);
@@ -1416,11 +1414,11 @@ static void work_fn_rx(struct work_struct *work)
 			sh_desc->partial, sh_desc->cookie);
 
 		spin_lock_irqsave(&port->lock, flags);
-		count = sci_dma_rx_push(s, tty, sh_desc->partial);
+		count = sci_dma_rx_push(s, sh_desc->partial);
 		spin_unlock_irqrestore(&port->lock, flags);
 
 		if (count)
-			tty_flip_buffer_push(tty);
+			tty_flip_buffer_push(&port->state->port);
 
 		sci_submit_rx(s);
 
diff --git a/drivers/tty/serial/sirfsoc_uart.c b/drivers/tty/serial/sirfsoc_uart.c
index 5da5cb96276..6bbfe9934a4 100644
--- a/drivers/tty/serial/sirfsoc_uart.c
+++ b/drivers/tty/serial/sirfsoc_uart.c
@@ -75,6 +75,20 @@ static struct sirfsoc_uart_port sirfsoc_uart_ports[SIRFSOC_UART_NR] = {
 			.line		= 2,
 		},
 	},
+	[3] = {
+		.port = {
+			.iotype		= UPIO_MEM,
+			.flags		= UPF_BOOT_AUTOCONF,
+			.line		= 3,
+		},
+	},
+	[4] = {
+		.port = {
+			.iotype		= UPIO_MEM,
+			.flags		= UPF_BOOT_AUTOCONF,
+			.line		= 4,
+		},
+	},
 };
 
 static inline struct sirfsoc_uart_port *to_sirfport(struct uart_port *port)
@@ -192,11 +206,6 @@ static unsigned int
 sirfsoc_uart_pio_rx_chars(struct uart_port *port, unsigned int max_rx_count)
 {
 	unsigned int ch, rx_count = 0;
-	struct tty_struct *tty;
-
-	tty = tty_port_tty_get(&port->state->port);
-	if (!tty)
-		return -ENODEV;
 
 	while (!(rd_regl(port, SIRFUART_RX_FIFO_STATUS) &
 					SIRFUART_FIFOEMPTY_MASK(port))) {
@@ -210,8 +219,7 @@ sirfsoc_uart_pio_rx_chars(struct uart_port *port, unsigned int max_rx_count)
 	}
 
 	port->icount.rx += rx_count;
-	tty_flip_buffer_push(tty);
-	tty_kref_put(tty);
+	tty_flip_buffer_push(&port->state->port);
 
 	return rx_count;
 }
@@ -245,6 +253,7 @@ static irqreturn_t sirfsoc_uart_isr(int irq, void *dev_id)
 	struct uart_port *port = &sirfport->port;
 	struct uart_state *state = port->state;
 	struct circ_buf *xmit = &port->state->xmit;
+	spin_lock(&port->lock);
 	intr_status = rd_regl(port, SIRFUART_INT_STATUS);
 	wr_regl(port, SIRFUART_INT_STATUS, intr_status);
 	intr_status &= rd_regl(port, SIRFUART_INT_EN);
@@ -254,6 +263,7 @@ static irqreturn_t sirfsoc_uart_isr(int irq, void *dev_id)
 				goto recv_char;
 			uart_insert_char(port, intr_status,
 					SIRFUART_RX_OFLOW, 0, TTY_BREAK);
+			spin_unlock(&port->lock);
 			return IRQ_HANDLED;
 		}
 		if (intr_status & SIRFUART_RX_OFLOW)
@@ -286,6 +296,7 @@ recv_char:
 		sirfsoc_uart_pio_rx_chars(port, SIRFSOC_UART_IO_RX_MAX_CNT);
 	if (intr_status & SIRFUART_TX_INT_EN) {
 		if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
+			spin_unlock(&port->lock);
 			return IRQ_HANDLED;
 		} else {
 			sirfsoc_uart_pio_tx_chars(sirfport,
@@ -296,6 +307,7 @@ recv_char:
 				sirfsoc_uart_stop_tx(port);
 		}
 	}
+	spin_unlock(&port->lock);
 	return IRQ_HANDLED;
 }
 
@@ -345,7 +357,6 @@ static void sirfsoc_uart_set_termios(struct uart_port *port,
 				       struct ktermios *old)
 {
 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
-	unsigned long	ioclk_rate;
 	unsigned long	config_reg = 0;
 	unsigned long	baud_rate;
 	unsigned long	setted_baud;
@@ -357,7 +368,6 @@ static void sirfsoc_uart_set_termios(struct uart_port *port,
 	int		threshold_div;
 	int		temp;
 
-	ioclk_rate = 150000000;
 	switch (termios->c_cflag & CSIZE) {
 	default:
 	case CS8:
@@ -413,14 +423,17 @@ static void sirfsoc_uart_set_termios(struct uart_port *port,
 			sirfsoc_uart_disable_ms(port);
 	}
 
-	/* common rate: fast calculation */
-	for (ic = 0; ic < SIRF_BAUD_RATE_SUPPORT_NR; ic++)
-		if (baud_rate == baudrate_to_regv[ic].baud_rate)
-			clk_div_reg = baudrate_to_regv[ic].reg_val;
+	if (port->uartclk == 150000000) {
+		/* common rate: fast calculation */
+		for (ic = 0; ic < SIRF_BAUD_RATE_SUPPORT_NR; ic++)
+			if (baud_rate == baudrate_to_regv[ic].baud_rate)
+				clk_div_reg = baudrate_to_regv[ic].reg_val;
+	}
+
 	setted_baud = baud_rate;
 	/* arbitary rate setting */
 	if (unlikely(clk_div_reg == 0))
-		clk_div_reg = sirfsoc_calc_sample_div(baud_rate, ioclk_rate,
+		clk_div_reg = sirfsoc_calc_sample_div(baud_rate, port->uartclk,
 								&setted_baud);
 	wr_regl(port, SIRFUART_DIVISOR, clk_div_reg);
 
@@ -679,6 +692,14 @@ int sirfsoc_uart_probe(struct platform_device *pdev)
 			goto err;
 	}
 
+	sirfport->clk = clk_get(&pdev->dev, NULL);
+	if (IS_ERR(sirfport->clk)) {
+		ret = PTR_ERR(sirfport->clk);
+		goto clk_err;
+	}
+	clk_prepare_enable(sirfport->clk);
+	port->uartclk = clk_get_rate(sirfport->clk);
+
 	port->ops = &sirfsoc_uart_ops;
 	spin_lock_init(&port->lock);
 
@@ -692,6 +713,9 @@ int sirfsoc_uart_probe(struct platform_device *pdev)
 	return 0;
 
 port_err:
+	clk_disable_unprepare(sirfport->clk);
+	clk_put(sirfport->clk);
+clk_err:
 	platform_set_drvdata(pdev, NULL);
 	if (sirfport->hw_flow_ctrl)
 		pinctrl_put(sirfport->p);
@@ -706,6 +730,8 @@ static int sirfsoc_uart_remove(struct platform_device *pdev)
 	platform_set_drvdata(pdev, NULL);
 	if (sirfport->hw_flow_ctrl)
 		pinctrl_put(sirfport->p);
+	clk_disable_unprepare(sirfport->clk);
+	clk_put(sirfport->clk);
 	uart_remove_one_port(&sirfsoc_uart_drv, port);
 	return 0;
 }
@@ -729,6 +755,7 @@ static int sirfsoc_uart_resume(struct platform_device *pdev)
 
 static struct of_device_id sirfsoc_uart_ids[] = {
 	{ .compatible = "sirf,prima2-uart", },
+	{ .compatible = "sirf,marco-uart", },
 	{}
 };
 MODULE_DEVICE_TABLE(of, sirfsoc_serial_of_match);
diff --git a/drivers/tty/serial/sirfsoc_uart.h b/drivers/tty/serial/sirfsoc_uart.h
index 6e207fdc2fe..85328ba0c4e 100644
--- a/drivers/tty/serial/sirfsoc_uart.h
+++ b/drivers/tty/serial/sirfsoc_uart.h
@@ -139,7 +139,7 @@
 #define SIRFSOC_UART_MINOR			0
 #define SIRFUART_PORT_NAME			"sirfsoc-uart"
 #define SIRFUART_MAP_SIZE			0x200
-#define SIRFSOC_UART_NR				3
+#define SIRFSOC_UART_NR				5
 #define SIRFSOC_PORT_TYPE			0xa5
 
 /* Baud Rate Calculation */
@@ -163,6 +163,7 @@ struct sirfsoc_uart_port {
 
 	struct uart_port		port;
 	struct pinctrl			*p;
+	struct clk			*clk;
 };
 
 /* Hardware Flow Control */
diff --git a/drivers/tty/serial/sn_console.c b/drivers/tty/serial/sn_console.c
index 1c6de9f5869..f51ffdc696f 100644
--- a/drivers/tty/serial/sn_console.c
+++ b/drivers/tty/serial/sn_console.c
@@ -457,8 +457,8 @@ static int sn_debug_printf(const char *fmt, ...)
 static void
 sn_receive_chars(struct sn_cons_port *port, unsigned long flags)
 {
+	struct tty_port *tport = NULL;
 	int ch;
-	struct tty_struct *tty;
 
 	if (!port) {
 		printk(KERN_ERR "sn_receive_chars - port NULL so can't receive\n");
@@ -472,11 +472,7 @@ sn_receive_chars(struct sn_cons_port *port, unsigned long flags)
 
 	if (port->sc_port.state) {
 		/* The serial_core stuffs are initialized, use them */
-		tty = port->sc_port.state->port.tty;
-	}
-	else {
-		/* Not registered yet - can't pass to tty layer.  */
-		tty = NULL;
+		tport = &port->sc_port.state->port;
 	}
 
 	while (port->sc_ops->sal_input_pending()) {
@@ -516,15 +512,15 @@ sn_receive_chars(struct sn_cons_port *port, unsigned long flags)
 #endif /* CONFIG_MAGIC_SYSRQ */
 
 		/* record the character to pass up to the tty layer */
-		if (tty) {
-			if(tty_insert_flip_char(tty, ch, TTY_NORMAL) == 0)
+		if (tport) {
+			if (tty_insert_flip_char(tport, ch, TTY_NORMAL) == 0)
 				break;
 		}
 		port->sc_port.icount.rx++;
 	}
 
-	if (tty)
-		tty_flip_buffer_push(tty);
+	if (tport)
+		tty_flip_buffer_push(tport);
 }
 
 /**
diff --git a/drivers/tty/serial/sunhv.c b/drivers/tty/serial/sunhv.c
index b9bf9c53f7f..ba60708053e 100644
--- a/drivers/tty/serial/sunhv.c
+++ b/drivers/tty/serial/sunhv.c
@@ -72,7 +72,7 @@ static void transmit_chars_write(struct uart_port *port, struct circ_buf *xmit)
 	}
 }
 
-static int receive_chars_getchar(struct uart_port *port, struct tty_struct *tty)
+static int receive_chars_getchar(struct uart_port *port)
 {
 	int saw_console_brk = 0;
 	int limit = 10000;
@@ -99,7 +99,7 @@ static int receive_chars_getchar(struct uart_port *port, struct tty_struct *tty)
 			uart_handle_dcd_change(port, 1);
 		}
 
-		if (tty == NULL) {
+		if (port->state == NULL) {
 			uart_handle_sysrq_char(port, c);
 			continue;
 		}
@@ -109,13 +109,13 @@ static int receive_chars_getchar(struct uart_port *port, struct tty_struct *tty)
 		if (uart_handle_sysrq_char(port, c))
 			continue;
 
-		tty_insert_flip_char(tty, c, TTY_NORMAL);
+		tty_insert_flip_char(&port->state->port, c, TTY_NORMAL);
 	}
 
 	return saw_console_brk;
 }
 
-static int receive_chars_read(struct uart_port *port, struct tty_struct *tty)
+static int receive_chars_read(struct uart_port *port)
 {
 	int saw_console_brk = 0;
 	int limit = 10000;
@@ -152,12 +152,13 @@ static int receive_chars_read(struct uart_port *port, struct tty_struct *tty)
 		for (i = 0; i < bytes_read; i++)
 			uart_handle_sysrq_char(port, con_read_page[i]);
 
-		if (tty == NULL)
+		if (port->state == NULL)
 			continue;
 
 		port->icount.rx += bytes_read;
 
-		tty_insert_flip_string(tty, con_read_page, bytes_read);
+		tty_insert_flip_string(&port->state->port, con_read_page,
+				bytes_read);
 	}
 
 	return saw_console_brk;
@@ -165,7 +166,7 @@ static int receive_chars_read(struct uart_port *port, struct tty_struct *tty)
 
 struct sunhv_ops {
 	void (*transmit_chars)(struct uart_port *port, struct circ_buf *xmit);
-	int (*receive_chars)(struct uart_port *port, struct tty_struct *tty);
+	int (*receive_chars)(struct uart_port *port);
 };
 
 static struct sunhv_ops bychar_ops = {
@@ -180,17 +181,17 @@ static struct sunhv_ops bywrite_ops = {
 
 static struct sunhv_ops *sunhv_ops = &bychar_ops;
 
-static struct tty_struct *receive_chars(struct uart_port *port)
+static struct tty_port *receive_chars(struct uart_port *port)
 {
-	struct tty_struct *tty = NULL;
+	struct tty_port *tport = NULL;
 
 	if (port->state != NULL)		/* Unopened serial console */
-		tty = port->state->port.tty;
+		tport = &port->state->port;
 
-	if (sunhv_ops->receive_chars(port, tty))
+	if (sunhv_ops->receive_chars(port))
 		sun_do_break();
 
-	return tty;
+	return tport;
 }
 
 static void transmit_chars(struct uart_port *port)
@@ -213,16 +214,16 @@ static void transmit_chars(struct uart_port *port)
 static irqreturn_t sunhv_interrupt(int irq, void *dev_id)
 {
 	struct uart_port *port = dev_id;
-	struct tty_struct *tty;
+	struct tty_port *tport;
 	unsigned long flags;
 
 	spin_lock_irqsave(&port->lock, flags);
-	tty = receive_chars(port);
+	tport = receive_chars(port);
 	transmit_chars(port);
 	spin_unlock_irqrestore(&port->lock, flags);
 
-	if (tty)
-		tty_flip_buffer_push(tty);
+	if (tport)
+		tty_flip_buffer_push(tport);
 
 	return IRQ_HANDLED;
 }
diff --git a/drivers/tty/serial/sunsab.c b/drivers/tty/serial/sunsab.c
index bd8b3b63410..8de2213664e 100644
--- a/drivers/tty/serial/sunsab.c
+++ b/drivers/tty/serial/sunsab.c
@@ -107,11 +107,11 @@ static __inline__ void sunsab_cec_wait(struct uart_sunsab_port *up)
 		udelay(1);
 }
 
-static struct tty_struct *
+static struct tty_port *
 receive_chars(struct uart_sunsab_port *up,
 	      union sab82532_irq_status *stat)
 {
-	struct tty_struct *tty = NULL;
+	struct tty_port *port = NULL;
 	unsigned char buf[32];
 	int saw_console_brk = 0;
 	int free_fifo = 0;
@@ -119,7 +119,7 @@ receive_chars(struct uart_sunsab_port *up,
 	int i;
 
 	if (up->port.state != NULL)		/* Unopened serial console */
-		tty = up->port.state->port.tty;
+		port = &up->port.state->port;
 
 	/* Read number of BYTES (Character + Status) available. */
 	if (stat->sreg.isr0 & SAB82532_ISR0_RPF) {
@@ -136,7 +136,7 @@ receive_chars(struct uart_sunsab_port *up,
 	if (stat->sreg.isr0 & SAB82532_ISR0_TIME) {
 		sunsab_cec_wait(up);
 		writeb(SAB82532_CMDR_RFRD, &up->regs->w.cmdr);
-		return tty;
+		return port;
 	}
 
 	if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
@@ -160,11 +160,6 @@ receive_chars(struct uart_sunsab_port *up,
 	for (i = 0; i < count; i++) {
 		unsigned char ch = buf[i], flag;
 
-		if (tty == NULL) {
-			uart_handle_sysrq_char(&up->port, ch);
-			continue;
-		}
-
 		flag = TTY_NORMAL;
 		up->port.icount.rx++;
 
@@ -213,15 +208,15 @@ receive_chars(struct uart_sunsab_port *up,
 
 		if ((stat->sreg.isr0 & (up->port.ignore_status_mask & 0xff)) == 0 &&
 		    (stat->sreg.isr1 & ((up->port.ignore_status_mask >> 8) & 0xff)) == 0)
-			tty_insert_flip_char(tty, ch, flag);
+			tty_insert_flip_char(port, ch, flag);
 		if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
-			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+			tty_insert_flip_char(port, 0, TTY_OVERRUN);
 	}
 
 	if (saw_console_brk)
 		sun_do_break();
 
-	return tty;
+	return port;
 }
 
 static void sunsab_stop_tx(struct uart_port *);
@@ -304,7 +299,7 @@ static void check_status(struct uart_sunsab_port *up,
 static irqreturn_t sunsab_interrupt(int irq, void *dev_id)
 {
 	struct uart_sunsab_port *up = dev_id;
-	struct tty_struct *tty;
+	struct tty_port *port = NULL;
 	union sab82532_irq_status status;
 	unsigned long flags;
 	unsigned char gis;
@@ -318,12 +313,11 @@ static irqreturn_t sunsab_interrupt(int irq, void *dev_id)
 	if (gis & 2)
 		status.sreg.isr1 = readb(&up->regs->r.isr1);
 
-	tty = NULL;
 	if (status.stat) {
 		if ((status.sreg.isr0 & (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
 					 SAB82532_ISR0_RFO | SAB82532_ISR0_RPF)) ||
 		    (status.sreg.isr1 & SAB82532_ISR1_BRK))
-			tty = receive_chars(up, &status);
+			port = receive_chars(up, &status);
 		if ((status.sreg.isr0 & SAB82532_ISR0_CDSC) ||
 		    (status.sreg.isr1 & SAB82532_ISR1_CSC))
 			check_status(up, &status);
@@ -333,8 +327,8 @@ static irqreturn_t sunsab_interrupt(int irq, void *dev_id)
 
 	spin_unlock_irqrestore(&up->port.lock, flags);
 
-	if (tty)
-		tty_flip_buffer_push(tty);
+	if (port)
+		tty_flip_buffer_push(port);
 
 	return IRQ_HANDLED;
 }
diff --git a/drivers/tty/serial/sunsu.c b/drivers/tty/serial/sunsu.c
index 220da3f9724..e343d667085 100644
--- a/drivers/tty/serial/sunsu.c
+++ b/drivers/tty/serial/sunsu.c
@@ -315,10 +315,10 @@ static void sunsu_enable_ms(struct uart_port *port)
 	spin_unlock_irqrestore(&up->port.lock, flags);
 }
 
-static struct tty_struct *
+static void
 receive_chars(struct uart_sunsu_port *up, unsigned char *status)
 {
-	struct tty_struct *tty = up->port.state->port.tty;
+	struct tty_port *port = &up->port.state->port;
 	unsigned char ch, flag;
 	int max_count = 256;
 	int saw_console_brk = 0;
@@ -376,22 +376,20 @@ receive_chars(struct uart_sunsu_port *up, unsigned char *status)
 		if (uart_handle_sysrq_char(&up->port, ch))
 			goto ignore_char;
 		if ((*status & up->port.ignore_status_mask) == 0)
-			tty_insert_flip_char(tty, ch, flag);
+			tty_insert_flip_char(port, ch, flag);
 		if (*status & UART_LSR_OE)
 			/*
 			 * Overrun is special, since it's reported
 			 * immediately, and doesn't affect the current
 			 * character.
 			 */
-			 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+			 tty_insert_flip_char(port, 0, TTY_OVERRUN);
 	ignore_char:
 		*status = serial_inp(up, UART_LSR);
 	} while ((*status & UART_LSR_DR) && (max_count-- > 0));
 
 	if (saw_console_brk)
 		sun_do_break();
-
-	return tty;
 }
 
 static void transmit_chars(struct uart_sunsu_port *up)
@@ -460,20 +458,16 @@ static irqreturn_t sunsu_serial_interrupt(int irq, void *dev_id)
 	spin_lock_irqsave(&up->port.lock, flags);
 
 	do {
-		struct tty_struct *tty;
-
 		status = serial_inp(up, UART_LSR);
-		tty = NULL;
 		if (status & UART_LSR_DR)
-			tty = receive_chars(up, &status);
+			receive_chars(up, &status);
 		check_modem_status(up);
 		if (status & UART_LSR_THRE)
 			transmit_chars(up);
 
 		spin_unlock_irqrestore(&up->port.lock, flags);
 
-		if (tty)
-			tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(&up->port.state->port);
 
 		spin_lock_irqsave(&up->port.lock, flags);
 
diff --git a/drivers/tty/serial/sunzilog.c b/drivers/tty/serial/sunzilog.c
index aef4fab957c..27669ff3d44 100644
--- a/drivers/tty/serial/sunzilog.c
+++ b/drivers/tty/serial/sunzilog.c
@@ -323,17 +323,15 @@ static void sunzilog_kbdms_receive_chars(struct uart_sunzilog_port *up,
 	}
 }
 
-static struct tty_struct *
+static struct tty_port *
 sunzilog_receive_chars(struct uart_sunzilog_port *up,
 		       struct zilog_channel __iomem *channel)
 {
-	struct tty_struct *tty;
+	struct tty_port *port = NULL;
 	unsigned char ch, r1, flag;
 
-	tty = NULL;
-	if (up->port.state != NULL &&		/* Unopened serial console */
-	    up->port.state->port.tty != NULL)	/* Keyboard || mouse */
-		tty = up->port.state->port.tty;
+	if (up->port.state != NULL)		/* Unopened serial console */
+		port = &up->port.state->port;
 
 	for (;;) {
 
@@ -366,11 +364,6 @@ sunzilog_receive_chars(struct uart_sunzilog_port *up,
 			continue;
 		}
 
-		if (tty == NULL) {
-			uart_handle_sysrq_char(&up->port, ch);
-			continue;
-		}
-
 		/* A real serial line, record the character and status.  */
 		flag = TTY_NORMAL;
 		up->port.icount.rx++;
@@ -400,13 +393,13 @@ sunzilog_receive_chars(struct uart_sunzilog_port *up,
 
 		if (up->port.ignore_status_mask == 0xff ||
 		    (r1 & up->port.ignore_status_mask) == 0) {
-		    	tty_insert_flip_char(tty, ch, flag);
+		    	tty_insert_flip_char(port, ch, flag);
 		}
 		if (r1 & Rx_OVR)
-			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+			tty_insert_flip_char(port, 0, TTY_OVERRUN);
 	}
 
-	return tty;
+	return port;
 }
 
 static void sunzilog_status_handle(struct uart_sunzilog_port *up,
@@ -539,21 +532,21 @@ static irqreturn_t sunzilog_interrupt(int irq, void *dev_id)
 	while (up) {
 		struct zilog_channel __iomem *channel
 			= ZILOG_CHANNEL_FROM_PORT(&up->port);
-		struct tty_struct *tty;
+		struct tty_port *port;
 		unsigned char r3;
 
 		spin_lock(&up->port.lock);
 		r3 = read_zsreg(channel, R3);
 
 		/* Channel A */
-		tty = NULL;
+		port = NULL;
 		if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
 			writeb(RES_H_IUS, &channel->control);
 			ZSDELAY();
 			ZS_WSYNC(channel);
 
 			if (r3 & CHARxIP)
-				tty = sunzilog_receive_chars(up, channel);
+				port = sunzilog_receive_chars(up, channel);
 			if (r3 & CHAEXT)
 				sunzilog_status_handle(up, channel);
 			if (r3 & CHATxIP)
@@ -561,22 +554,22 @@ static irqreturn_t sunzilog_interrupt(int irq, void *dev_id)
 		}
 		spin_unlock(&up->port.lock);
 
-		if (tty)
-			tty_flip_buffer_push(tty);
+		if (port)
+			tty_flip_buffer_push(port);
 
 		/* Channel B */
 		up = up->next;
 		channel = ZILOG_CHANNEL_FROM_PORT(&up->port);
 
 		spin_lock(&up->port.lock);
-		tty = NULL;
+		port = NULL;
 		if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
 			writeb(RES_H_IUS, &channel->control);
 			ZSDELAY();
 			ZS_WSYNC(channel);
 
 			if (r3 & CHBRxIP)
-				tty = sunzilog_receive_chars(up, channel);
+				port = sunzilog_receive_chars(up, channel);
 			if (r3 & CHBEXT)
 				sunzilog_status_handle(up, channel);
 			if (r3 & CHBTxIP)
@@ -584,8 +577,8 @@ static irqreturn_t sunzilog_interrupt(int irq, void *dev_id)
 		}
 		spin_unlock(&up->port.lock);
 
-		if (tty)
-			tty_flip_buffer_push(tty);
+		if (port)
+			tty_flip_buffer_push(port);
 
 		up = up->next;
 	}
diff --git a/drivers/tty/serial/timbuart.c b/drivers/tty/serial/timbuart.c
index 5be0d68fece..6818410a2be 100644
--- a/drivers/tty/serial/timbuart.c
+++ b/drivers/tty/serial/timbuart.c
@@ -91,16 +91,16 @@ static void timbuart_flush_buffer(struct uart_port *port)
 
 static void timbuart_rx_chars(struct uart_port *port)
 {
-	struct tty_struct *tty = port->state->port.tty;
+	struct tty_port *tport = &port->state->port;
 
 	while (ioread32(port->membase + TIMBUART_ISR) & RXDP) {
 		u8 ch = ioread8(port->membase + TIMBUART_RXFIFO);
 		port->icount.rx++;
-		tty_insert_flip_char(tty, ch, TTY_NORMAL);
+		tty_insert_flip_char(tport, ch, TTY_NORMAL);
 	}
 
 	spin_unlock(&port->lock);
-	tty_flip_buffer_push(port->state->port.tty);
+	tty_flip_buffer_push(tport);
 	spin_lock(&port->lock);
 
 	dev_dbg(port->dev, "%s - total read %d bytes\n",
diff --git a/drivers/tty/serial/uartlite.c b/drivers/tty/serial/uartlite.c
index 89eee43c4e2..5f90ef24d47 100644
--- a/drivers/tty/serial/uartlite.c
+++ b/drivers/tty/serial/uartlite.c
@@ -19,7 +19,7 @@
 #include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <linux/init.h>
-#include <asm/io.h>
+#include <linux/io.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/of_device.h>
@@ -34,7 +34,7 @@
  * Register definitions
  *
  * For register details see datasheet:
- * http://www.xilinx.com/support/documentation/ip_documentation/opb_uartlite.pdf 
+ * http://www.xilinx.com/support/documentation/ip_documentation/opb_uartlite.pdf
  */
 
 #define ULITE_RX		0x00
@@ -57,6 +57,54 @@
 #define ULITE_CONTROL_RST_RX	0x02
 #define ULITE_CONTROL_IE	0x10
 
+struct uartlite_reg_ops {
+	u32 (*in)(void __iomem *addr);
+	void (*out)(u32 val, void __iomem *addr);
+};
+
+static u32 uartlite_inbe32(void __iomem *addr)
+{
+	return ioread32be(addr);
+}
+
+static void uartlite_outbe32(u32 val, void __iomem *addr)
+{
+	iowrite32be(val, addr);
+}
+
+static struct uartlite_reg_ops uartlite_be = {
+	.in = uartlite_inbe32,
+	.out = uartlite_outbe32,
+};
+
+static u32 uartlite_inle32(void __iomem *addr)
+{
+	return ioread32(addr);
+}
+
+static void uartlite_outle32(u32 val, void __iomem *addr)
+{
+	iowrite32(val, addr);
+}
+
+static struct uartlite_reg_ops uartlite_le = {
+	.in = uartlite_inle32,
+	.out = uartlite_outle32,
+};
+
+static inline u32 uart_in32(u32 offset, struct uart_port *port)
+{
+	struct uartlite_reg_ops *reg_ops = port->private_data;
+
+	return reg_ops->in(port->membase + offset);
+}
+
+static inline void uart_out32(u32 val, u32 offset, struct uart_port *port)
+{
+	struct uartlite_reg_ops *reg_ops = port->private_data;
+
+	reg_ops->out(val, port->membase + offset);
+}
 
 static struct uart_port ulite_ports[ULITE_NR_UARTS];
 
@@ -66,7 +114,7 @@ static struct uart_port ulite_ports[ULITE_NR_UARTS];
 
 static int ulite_receive(struct uart_port *port, int stat)
 {
-	struct tty_struct *tty = port->state->port.tty;
+	struct tty_port *tport = &port->state->port;
 	unsigned char ch = 0;
 	char flag = TTY_NORMAL;
 
@@ -77,7 +125,7 @@ static int ulite_receive(struct uart_port *port, int stat)
 	/* stats */
 	if (stat & ULITE_STATUS_RXVALID) {
 		port->icount.rx++;
-		ch = ioread32be(port->membase + ULITE_RX);
+		ch = uart_in32(ULITE_RX, port);
 
 		if (stat & ULITE_STATUS_PARITY)
 			port->icount.parity++;
@@ -103,13 +151,13 @@ static int ulite_receive(struct uart_port *port, int stat)
 	stat &= ~port->ignore_status_mask;
 
 	if (stat & ULITE_STATUS_RXVALID)
-		tty_insert_flip_char(tty, ch, flag);
+		tty_insert_flip_char(tport, ch, flag);
 
 	if (stat & ULITE_STATUS_FRAME)
-		tty_insert_flip_char(tty, 0, TTY_FRAME);
+		tty_insert_flip_char(tport, 0, TTY_FRAME);
 
 	if (stat & ULITE_STATUS_OVERRUN)
-		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 
 	return 1;
 }
@@ -122,7 +170,7 @@ static int ulite_transmit(struct uart_port *port, int stat)
 		return 0;
 
 	if (port->x_char) {
-		iowrite32be(port->x_char, port->membase + ULITE_TX);
+		uart_out32(port->x_char, ULITE_TX, port);
 		port->x_char = 0;
 		port->icount.tx++;
 		return 1;
@@ -131,7 +179,7 @@ static int ulite_transmit(struct uart_port *port, int stat)
 	if (uart_circ_empty(xmit) || uart_tx_stopped(port))
 		return 0;
 
-	iowrite32be(xmit->buf[xmit->tail], port->membase + ULITE_TX);
+	uart_out32(xmit->buf[xmit->tail], ULITE_TX, port);
 	xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE-1);
 	port->icount.tx++;
 
@@ -148,7 +196,7 @@ static irqreturn_t ulite_isr(int irq, void *dev_id)
 	int busy, n = 0;
 
 	do {
-		int stat = ioread32be(port->membase + ULITE_STATUS);
+		int stat = uart_in32(ULITE_STATUS, port);
 		busy  = ulite_receive(port, stat);
 		busy |= ulite_transmit(port, stat);
 		n++;
@@ -156,7 +204,7 @@ static irqreturn_t ulite_isr(int irq, void *dev_id)
 
 	/* work done? */
 	if (n > 1) {
-		tty_flip_buffer_push(port->state->port.tty);
+		tty_flip_buffer_push(&port->state->port);
 		return IRQ_HANDLED;
 	} else {
 		return IRQ_NONE;
@@ -169,7 +217,7 @@ static unsigned int ulite_tx_empty(struct uart_port *port)
 	unsigned int ret;
 
 	spin_lock_irqsave(&port->lock, flags);
-	ret = ioread32be(port->membase + ULITE_STATUS);
+	ret = uart_in32(ULITE_STATUS, port);
 	spin_unlock_irqrestore(&port->lock, flags);
 
 	return ret & ULITE_STATUS_TXEMPTY ? TIOCSER_TEMT : 0;
@@ -192,7 +240,7 @@ static void ulite_stop_tx(struct uart_port *port)
 
 static void ulite_start_tx(struct uart_port *port)
 {
-	ulite_transmit(port, ioread32be(port->membase + ULITE_STATUS));
+	ulite_transmit(port, uart_in32(ULITE_STATUS, port));
 }
 
 static void ulite_stop_rx(struct uart_port *port)
@@ -220,17 +268,17 @@ static int ulite_startup(struct uart_port *port)
 	if (ret)
 		return ret;
 
-	iowrite32be(ULITE_CONTROL_RST_RX | ULITE_CONTROL_RST_TX,
-	       port->membase + ULITE_CONTROL);
-	iowrite32be(ULITE_CONTROL_IE, port->membase + ULITE_CONTROL);
+	uart_out32(ULITE_CONTROL_RST_RX | ULITE_CONTROL_RST_TX,
+		ULITE_CONTROL, port);
+	uart_out32(ULITE_CONTROL_IE, ULITE_CONTROL, port);
 
 	return 0;
 }
 
 static void ulite_shutdown(struct uart_port *port)
 {
-	iowrite32be(0, port->membase + ULITE_CONTROL);
-	ioread32be(port->membase + ULITE_CONTROL); /* dummy */
+	uart_out32(0, ULITE_CONTROL, port);
+	uart_in32(ULITE_CONTROL, port); /* dummy */
 	free_irq(port->irq, port);
 }
 
@@ -281,6 +329,8 @@ static void ulite_release_port(struct uart_port *port)
 
 static int ulite_request_port(struct uart_port *port)
 {
+	int ret;
+
 	pr_debug("ulite console: port=%p; port->mapbase=%llx\n",
 		 port, (unsigned long long) port->mapbase);
 
@@ -296,6 +346,14 @@ static int ulite_request_port(struct uart_port *port)
 		return -EBUSY;
 	}
 
+	port->private_data = &uartlite_be;
+	ret = uart_in32(ULITE_CONTROL, port);
+	uart_out32(ULITE_CONTROL_RST_TX, ULITE_CONTROL, port);
+	ret = uart_in32(ULITE_STATUS, port);
+	/* Endianess detection */
+	if ((ret & ULITE_STATUS_TXEMPTY) != ULITE_STATUS_TXEMPTY)
+		port->private_data = &uartlite_le;
+
 	return 0;
 }
 
@@ -314,20 +372,19 @@ static int ulite_verify_port(struct uart_port *port, struct serial_struct *ser)
 #ifdef CONFIG_CONSOLE_POLL
 static int ulite_get_poll_char(struct uart_port *port)
 {
-	if (!(ioread32be(port->membase + ULITE_STATUS)
-						& ULITE_STATUS_RXVALID))
+	if (!(uart_in32(ULITE_STATUS, port) & ULITE_STATUS_RXVALID))
 		return NO_POLL_CHAR;
 
-	return ioread32be(port->membase + ULITE_RX);
+	return uart_in32(ULITE_RX, port);
 }
 
 static void ulite_put_poll_char(struct uart_port *port, unsigned char ch)
 {
-	while (ioread32be(port->membase + ULITE_STATUS) & ULITE_STATUS_TXFULL)
+	while (uart_in32(ULITE_STATUS, port) & ULITE_STATUS_TXFULL)
 		cpu_relax();
 
 	/* write char to device */
-	iowrite32be(ch, port->membase + ULITE_TX);
+	uart_out32(ch, ULITE_TX, port);
 }
 #endif
 
@@ -366,7 +423,7 @@ static void ulite_console_wait_tx(struct uart_port *port)
 
 	/* Spin waiting for TX fifo to have space available */
 	for (i = 0; i < 100000; i++) {
-		val = ioread32be(port->membase + ULITE_STATUS);
+		val = uart_in32(ULITE_STATUS, port);
 		if ((val & ULITE_STATUS_TXFULL) == 0)
 			break;
 		cpu_relax();
@@ -376,7 +433,7 @@ static void ulite_console_wait_tx(struct uart_port *port)
 static void ulite_console_putchar(struct uart_port *port, int ch)
 {
 	ulite_console_wait_tx(port);
-	iowrite32be(ch, port->membase + ULITE_TX);
+	uart_out32(ch, ULITE_TX, port);
 }
 
 static void ulite_console_write(struct console *co, const char *s,
@@ -393,8 +450,8 @@ static void ulite_console_write(struct console *co, const char *s,
 		spin_lock_irqsave(&port->lock, flags);
 
 	/* save and disable interrupt */
-	ier = ioread32be(port->membase + ULITE_STATUS) & ULITE_STATUS_IE;
-	iowrite32be(0, port->membase + ULITE_CONTROL);
+	ier = uart_in32(ULITE_STATUS, port) & ULITE_STATUS_IE;
+	uart_out32(0, ULITE_CONTROL, port);
 
 	uart_console_write(port, s, count, ulite_console_putchar);
 
@@ -402,7 +459,7 @@ static void ulite_console_write(struct console *co, const char *s,
 
 	/* restore interrupt state */
 	if (ier)
-		iowrite32be(ULITE_CONTROL_IE, port->membase + ULITE_CONTROL);
+		uart_out32(ULITE_CONTROL_IE, ULITE_CONTROL, port);
 
 	if (locked)
 		spin_unlock_irqrestore(&port->lock, flags);
@@ -615,7 +672,7 @@ static struct platform_driver ulite_platform_driver = {
  * Module setup/teardown
  */
 
-int __init ulite_init(void)
+static int __init ulite_init(void)
 {
 	int ret;
 
@@ -634,11 +691,11 @@ int __init ulite_init(void)
 err_plat:
 	uart_unregister_driver(&ulite_uart_driver);
 err_uart:
-	printk(KERN_ERR "registering uartlite driver failed: err=%i", ret);
+	pr_err("registering uartlite driver failed: err=%i", ret);
 	return ret;
 }
 
-void __exit ulite_exit(void)
+static void __exit ulite_exit(void)
 {
 	platform_driver_unregister(&ulite_platform_driver);
 	uart_unregister_driver(&ulite_uart_driver);
diff --git a/drivers/tty/serial/ucc_uart.c b/drivers/tty/serial/ucc_uart.c
index f99b0c965f8..7355303dad9 100644
--- a/drivers/tty/serial/ucc_uart.c
+++ b/drivers/tty/serial/ucc_uart.c
@@ -469,7 +469,7 @@ static void qe_uart_int_rx(struct uart_qe_port *qe_port)
 	int i;
 	unsigned char ch, *cp;
 	struct uart_port *port = &qe_port->port;
-	struct tty_struct *tty = port->state->port.tty;
+	struct tty_port *tport = &port->state->port;
 	struct qe_bd *bdp;
 	u16 status;
 	unsigned int flg;
@@ -491,7 +491,7 @@ static void qe_uart_int_rx(struct uart_qe_port *qe_port)
 		/* If we don't have enough room in RX buffer for the entire BD,
 		 * then we try later, which will be the next RX interrupt.
 		 */
-		if (tty_buffer_request_room(tty, i) < i) {
+		if (tty_buffer_request_room(tport, i) < i) {
 			dev_dbg(port->dev, "ucc-uart: no room in RX buffer\n");
 			return;
 		}
@@ -512,7 +512,7 @@ static void qe_uart_int_rx(struct uart_qe_port *qe_port)
 				continue;
 
 error_return:
-			tty_insert_flip_char(tty, ch, flg);
+			tty_insert_flip_char(tport, ch, flg);
 
 		}
 
@@ -530,7 +530,7 @@ error_return:
 	qe_port->rx_cur = bdp;
 
 	/* Activate BH processing */
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(tport);
 
 	return;
 
@@ -560,7 +560,7 @@ handle_error:
 
 	/* Overrun does not affect the current character ! */
 	if (status & BD_SC_OV)
-		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 #ifdef SUPPORT_SYSRQ
 	port->sysrq = 0;
 #endif
diff --git a/drivers/tty/serial/vr41xx_siu.c b/drivers/tty/serial/vr41xx_siu.c
index 62ee0166bc6..f655997f44a 100644
--- a/drivers/tty/serial/vr41xx_siu.c
+++ b/drivers/tty/serial/vr41xx_siu.c
@@ -313,12 +313,10 @@ static void siu_break_ctl(struct uart_port *port, int ctl)
 
 static inline void receive_chars(struct uart_port *port, uint8_t *status)
 {
-	struct tty_struct *tty;
 	uint8_t lsr, ch;
 	char flag;
 	int max_count = RX_MAX_COUNT;
 
-	tty = port->state->port.tty;
 	lsr = *status;
 
 	do {
@@ -365,7 +363,7 @@ static inline void receive_chars(struct uart_port *port, uint8_t *status)
 		lsr = siu_read(port, UART_LSR);
 	} while ((lsr & UART_LSR_DR) && (max_count-- > 0));
 
-	tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&port->state->port);
 
 	*status = lsr;
 }
diff --git a/drivers/tty/serial/vt8500_serial.c b/drivers/tty/serial/vt8500_serial.c
index d5ed9f61300..a3f9dd5c9df 100644
--- a/drivers/tty/serial/vt8500_serial.c
+++ b/drivers/tty/serial/vt8500_serial.c
@@ -136,22 +136,14 @@ static void vt8500_enable_ms(struct uart_port *port)
 
 static void handle_rx(struct uart_port *port)
 {
-	struct tty_struct *tty = tty_port_tty_get(&port->state->port);
-	if (!tty) {
-		/* Discard data: no tty available */
-		int count = (vt8500_read(port, VT8500_URFIDX) & 0x1f00) >> 8;
-		u16 ch;
-		while (count--)
-			ch = readw(port->membase + VT8500_RXFIFO);
-		return;
-	}
+	struct tty_port *tport = &port->state->port;
 
 	/*
 	 * Handle overrun
 	 */
 	if ((vt8500_read(port, VT8500_URISR) & RXOVER)) {
 		port->icount.overrun++;
-		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 	}
 
 	/* and now the main RX loop */
@@ -174,11 +166,10 @@ static void handle_rx(struct uart_port *port)
 		port->icount.rx++;
 
 		if (!uart_handle_sysrq_char(port, c))
-			tty_insert_flip_char(tty, c, flag);
+			tty_insert_flip_char(tport, c, flag);
 	}
 
-	tty_flip_buffer_push(tty);
-	tty_kref_put(tty);
+	tty_flip_buffer_push(tport);
 }
 
 static void handle_tx(struct uart_port *port)
@@ -569,7 +560,7 @@ static int vt8500_serial_probe(struct platform_device *pdev)
 
 	if (np)
 		port = of_alias_get_id(np, "serial");
-		if (port > VT8500_MAX_PORTS)
+		if (port >= VT8500_MAX_PORTS)
 			port = -1;
 	else
 		port = -1;
@@ -580,7 +571,7 @@ static int vt8500_serial_probe(struct platform_device *pdev)
 					sizeof(vt8500_ports_in_use));
 	}
 
-	if (port > VT8500_MAX_PORTS)
+	if (port >= VT8500_MAX_PORTS)
 		return -ENODEV;
 
 	/* reserve the port id */
@@ -589,10 +580,27 @@ static int vt8500_serial_probe(struct platform_device *pdev)
 		return -EBUSY;
 	}
 
-	vt8500_port = kzalloc(sizeof(struct vt8500_port), GFP_KERNEL);
+	vt8500_port = devm_kzalloc(&pdev->dev, sizeof(struct vt8500_port),
+				   GFP_KERNEL);
 	if (!vt8500_port)
 		return -ENOMEM;
 
+	vt8500_port->uart.membase = devm_request_and_ioremap(&pdev->dev, mmres);
+	if (!vt8500_port->uart.membase)
+		return -EADDRNOTAVAIL;
+
+	vt8500_port->clk = of_clk_get(pdev->dev.of_node, 0);
+	if (IS_ERR(vt8500_port->clk)) {
+		dev_err(&pdev->dev, "failed to get clock\n");
+		return  -EINVAL;
+	}
+
+	ret = clk_prepare_enable(vt8500_port->clk);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to enable clock\n");
+		return ret;
+	}
+
 	vt8500_port->uart.type = PORT_VT8500;
 	vt8500_port->uart.iotype = UPIO_MEM;
 	vt8500_port->uart.mapbase = mmres->start;
@@ -615,12 +623,6 @@ static int vt8500_serial_probe(struct platform_device *pdev)
 	snprintf(vt8500_port->name, sizeof(vt8500_port->name),
 		 "VT8500 UART%d", pdev->id);
 
-	vt8500_port->uart.membase = ioremap(mmres->start, resource_size(mmres));
-	if (!vt8500_port->uart.membase) {
-		ret = -ENOMEM;
-		goto err;
-	}
-
 	vt8500_uart_ports[port] = vt8500_port;
 
 	uart_add_one_port(&vt8500_uart_driver, &vt8500_port->uart);
@@ -628,10 +630,6 @@ static int vt8500_serial_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, vt8500_port);
 
 	return 0;
-
-err:
-	kfree(vt8500_port);
-	return ret;
 }
 
 static int vt8500_serial_remove(struct platform_device *pdev)
@@ -639,8 +637,8 @@ static int vt8500_serial_remove(struct platform_device *pdev)
 	struct vt8500_port *vt8500_port = platform_get_drvdata(pdev);
 
 	platform_set_drvdata(pdev, NULL);
+	clk_disable_unprepare(vt8500_port->clk);
 	uart_remove_one_port(&vt8500_uart_driver, &vt8500_port->uart);
-	kfree(vt8500_port);
 
 	return 0;
 }
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index 9ab910370c5..ba451c7209f 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -17,6 +17,7 @@
 #include <linux/tty.h>
 #include <linux/tty_flip.h>
 #include <linux/console.h>
+#include <linux/clk.h>
 #include <linux/irq.h>
 #include <linux/io.h>
 #include <linux/of.h>
@@ -147,15 +148,11 @@
 static irqreturn_t xuartps_isr(int irq, void *dev_id)
 {
 	struct uart_port *port = (struct uart_port *)dev_id;
-	struct tty_struct *tty;
 	unsigned long flags;
 	unsigned int isrstatus, numbytes;
 	unsigned int data;
 	char status = TTY_NORMAL;
 
-	/* Get the tty which could be NULL so don't assume it's valid */
-	tty = tty_port_tty_get(&port->state->port);
-
 	spin_lock_irqsave(&port->lock, flags);
 
 	/* Read the interrupt status register to determine which
@@ -187,14 +184,11 @@ static irqreturn_t xuartps_isr(int irq, void *dev_id)
 			} else if (isrstatus & XUARTPS_IXR_OVERRUN)
 				port->icount.overrun++;
 
-			if (tty)
-				uart_insert_char(port, isrstatus,
-						XUARTPS_IXR_OVERRUN, data,
-						status);
+			uart_insert_char(port, isrstatus, XUARTPS_IXR_OVERRUN,
+					data, status);
 		}
 		spin_unlock(&port->lock);
-		if (tty)
-			tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(&port->state->port);
 		spin_lock(&port->lock);
 	}
 
@@ -237,7 +231,6 @@ static irqreturn_t xuartps_isr(int irq, void *dev_id)
 
 	/* be sure to release the lock and tty before leaving */
 	spin_unlock_irqrestore(&port->lock, flags);
-	tty_kref_put(tty);
 
 	return IRQ_HANDLED;
 }
@@ -944,16 +937,18 @@ static int xuartps_probe(struct platform_device *pdev)
 	int rc;
 	struct uart_port *port;
 	struct resource *res, *res2;
-	int clk = 0;
-
-	const unsigned int *prop;
+	struct clk *clk;
 
-	prop = of_get_property(pdev->dev.of_node, "clock", NULL);
-	if (prop)
-		clk = be32_to_cpup(prop);
-	if (!clk) {
+	clk = of_clk_get(pdev->dev.of_node, 0);
+	if (IS_ERR(clk)) {
 		dev_err(&pdev->dev, "no clock specified\n");
-		return -ENODEV;
+		return PTR_ERR(clk);
+	}
+
+	rc = clk_prepare_enable(clk);
+	if (rc) {
+		dev_err(&pdev->dev, "could not enable clock\n");
+		return -EBUSY;
 	}
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -978,7 +973,8 @@ static int xuartps_probe(struct platform_device *pdev)
 		port->mapbase = res->start;
 		port->irq = res2->start;
 		port->dev = &pdev->dev;
-		port->uartclk = clk;
+		port->uartclk = clk_get_rate(clk);
+		port->private_data = clk;
 		dev_set_drvdata(&pdev->dev, port);
 		rc = uart_add_one_port(&xuartps_uart_driver, port);
 		if (rc) {
@@ -1000,14 +996,14 @@ static int xuartps_probe(struct platform_device *pdev)
 static int xuartps_remove(struct platform_device *pdev)
 {
 	struct uart_port *port = dev_get_drvdata(&pdev->dev);
-	int rc = 0;
+	struct clk *clk = port->private_data;
+	int rc;
 
 	/* Remove the xuartps port from the serial core */
-	if (port) {
-		rc = uart_remove_one_port(&xuartps_uart_driver, port);
-		dev_set_drvdata(&pdev->dev, NULL);
-		port->mapbase = 0;
-	}
+	rc = uart_remove_one_port(&xuartps_uart_driver, port);
+	dev_set_drvdata(&pdev->dev, NULL);
+	port->mapbase = 0;
+	clk_disable_unprepare(clk);
 	return rc;
 }
 
@@ -1048,7 +1044,7 @@ MODULE_DEVICE_TABLE(of, xuartps_of_match);
 
 static struct platform_driver xuartps_platform_driver = {
 	.probe   = xuartps_probe,		/* Probe method */
-	.remove  = __exit_p(xuartps_remove),	/* Detach method */
+	.remove  = xuartps_remove,		/* Detach method */
 	.suspend = xuartps_suspend,		/* Suspend */
 	.resume  = xuartps_resume,		/* Resume after a suspend */
 	.driver  = {
diff --git a/drivers/tty/serial/zs.c b/drivers/tty/serial/zs.c
index 92c00b24d0d..6a169877109 100644
--- a/drivers/tty/serial/zs.c
+++ b/drivers/tty/serial/zs.c
@@ -603,7 +603,7 @@ static void zs_receive_chars(struct zs_port *zport)
 		uart_insert_char(uport, status, Rx_OVR, ch, flag);
 	}
 
-	tty_flip_buffer_push(uport->state->port.tty);
+	tty_flip_buffer_push(&uport->state->port);
 }
 
 static void zs_raw_transmit_chars(struct zs_port *zport)
diff --git a/drivers/tty/synclink.c b/drivers/tty/synclink.c
index 9e071f6985f..8983276aa35 100644
--- a/drivers/tty/synclink.c
+++ b/drivers/tty/synclink.c
@@ -291,8 +291,7 @@ struct mgsl_struct {
 	bool lcr_mem_requested;
 
 	u32 misc_ctrl_value;
-	char flag_buf[MAX_ASYNC_BUFFER_SIZE];
-	char char_buf[MAX_ASYNC_BUFFER_SIZE];	
+	char *flag_buf;
 	bool drop_rts_on_tx_done;
 
 	bool loopmode_insert_requested;
@@ -1440,7 +1439,6 @@ static void mgsl_isr_receive_data( struct mgsl_struct *info )
 	u16 status;
 	int work = 0;
 	unsigned char DataByte;
- 	struct tty_struct *tty = info->port.tty;
  	struct	mgsl_icount *icount = &info->icount;
 	
 	if ( debug_level >= DEBUG_LEVEL_ISR )	
@@ -1502,19 +1500,19 @@ static void mgsl_isr_receive_data( struct mgsl_struct *info )
 			if (status & RXSTATUS_BREAK_RECEIVED) {
 				flag = TTY_BREAK;
 				if (info->port.flags & ASYNC_SAK)
-					do_SAK(tty);
+					do_SAK(info->port.tty);
 			} else if (status & RXSTATUS_PARITY_ERROR)
 				flag = TTY_PARITY;
 			else if (status & RXSTATUS_FRAMING_ERROR)
 				flag = TTY_FRAME;
 		}	/* end of if (error) */
-		tty_insert_flip_char(tty, DataByte, flag);
+		tty_insert_flip_char(&info->port, DataByte, flag);
 		if (status & RXSTATUS_OVERRUN) {
 			/* Overrun is special, since it's
 			 * reported immediately, and doesn't
 			 * affect the current character
 			 */
-			work += tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+			work += tty_insert_flip_char(&info->port, 0, TTY_OVERRUN);
 		}
 	}
 
@@ -1525,7 +1523,7 @@ static void mgsl_isr_receive_data( struct mgsl_struct *info )
 	}
 			
 	if(work)
-		tty_flip_buffer_push(tty);
+		tty_flip_buffer_push(&info->port);
 }
 
 /* mgsl_isr_misc()
@@ -1852,7 +1850,7 @@ static void shutdown(struct mgsl_struct * info)
 	usc_OutReg(info, PCR, (u16)((usc_InReg(info, PCR) | BIT13) | BIT12));
 
 	if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
- 		info->serial_signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
 		usc_set_serial_signals(info);
 	}
 
@@ -1917,12 +1915,12 @@ static void mgsl_change_params(struct mgsl_struct *info)
 			 
 	cflag = info->port.tty->termios.c_cflag;
 
-	/* if B0 rate (hangup) specified then negate DTR and RTS */
-	/* otherwise assert DTR and RTS */
+	/* if B0 rate (hangup) specified then negate RTS and DTR */
+	/* otherwise assert RTS and DTR */
  	if (cflag & CBAUD)
-		info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
+		info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
 	else
-		info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
 	
 	/* byte size and parity */
 	
@@ -3046,7 +3044,7 @@ static void mgsl_set_termios(struct tty_struct *tty, struct ktermios *old_termio
 	/* Handle transition to B0 status */
 	if (old_termios->c_cflag & CBAUD &&
 	    !(tty->termios.c_cflag & CBAUD)) {
-		info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
 		spin_lock_irqsave(&info->irq_spinlock,flags);
 	 	usc_set_serial_signals(info);
 		spin_unlock_irqrestore(&info->irq_spinlock,flags);
@@ -3245,9 +3243,9 @@ static void dtr_rts(struct tty_port *port, int on)
 
 	spin_lock_irqsave(&info->irq_spinlock,flags);
 	if (on)
-		info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
+		info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
 	else
-		info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
  	usc_set_serial_signals(info);
 	spin_unlock_irqrestore(&info->irq_spinlock,flags);
 }
@@ -3416,7 +3414,7 @@ static int mgsl_open(struct tty_struct *tty, struct file * filp)
 		goto cleanup;
 	}
 	
-	info->port.tty->low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
+	info->port.low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 
 	spin_lock_irqsave(&info->netlock, flags);
 	if (info->netcount) {
@@ -3898,7 +3896,13 @@ static int mgsl_alloc_intermediate_rxbuffer_memory(struct mgsl_struct *info)
 	info->intermediate_rxbuffer = kmalloc(info->max_frame_size, GFP_KERNEL | GFP_DMA);
 	if ( info->intermediate_rxbuffer == NULL )
 		return -ENOMEM;
-
+	/* unused flag buffer to satisfy receive_buf calling interface */
+	info->flag_buf = kzalloc(info->max_frame_size, GFP_KERNEL);
+	if (!info->flag_buf) {
+		kfree(info->intermediate_rxbuffer);
+		info->intermediate_rxbuffer = NULL;
+		return -ENOMEM;
+	}
 	return 0;
 
 }	/* end of mgsl_alloc_intermediate_rxbuffer_memory() */
@@ -3917,6 +3921,8 @@ static void mgsl_free_intermediate_rxbuffer_memory(struct mgsl_struct *info)
 {
 	kfree(info->intermediate_rxbuffer);
 	info->intermediate_rxbuffer = NULL;
+	kfree(info->flag_buf);
+	info->flag_buf = NULL;
 
 }	/* end of mgsl_free_intermediate_rxbuffer_memory() */
 
@@ -6233,8 +6239,8 @@ static void usc_get_serial_signals( struct mgsl_struct *info )
 {
 	u16 status;
 
-	/* clear all serial signals except DTR and RTS */
-	info->serial_signals &= SerialSignal_DTR + SerialSignal_RTS;
+	/* clear all serial signals except RTS and DTR */
+	info->serial_signals &= SerialSignal_RTS | SerialSignal_DTR;
 
 	/* Read the Misc Interrupt status Register (MISR) to get */
 	/* the V24 status signals. */
@@ -6259,7 +6265,7 @@ static void usc_get_serial_signals( struct mgsl_struct *info )
 
 /* usc_set_serial_signals()
  *
- *	Set the state of DTR and RTS based on contents of
+ *	Set the state of RTS and DTR based on contents of
  *	serial_signals member of device extension.
  *	
  * Arguments:		info	pointer to device instance data
@@ -7773,8 +7779,8 @@ static int hdlcdev_open(struct net_device *dev)
 		return rc;
 	}
 
-	/* assert DTR and RTS, apply hardware settings */
-	info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
+	/* assert RTS and DTR, apply hardware settings */
+	info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
 	mgsl_program_hw(info);
 
 	/* enable network layer transmit */
diff --git a/drivers/tty/synclink_gt.c b/drivers/tty/synclink_gt.c
index aba1e59f4a8..aa9eece35c3 100644
--- a/drivers/tty/synclink_gt.c
+++ b/drivers/tty/synclink_gt.c
@@ -317,8 +317,7 @@ struct slgt_info {
 	unsigned char *tx_buf;
 	int tx_count;
 
-	char flag_buf[MAX_ASYNC_BUFFER_SIZE];
-	char char_buf[MAX_ASYNC_BUFFER_SIZE];
+	char *flag_buf;
 	bool drop_rts_on_tx_done;
 	struct	_input_signal_events	input_signal_events;
 
@@ -683,7 +682,7 @@ static int open(struct tty_struct *tty, struct file *filp)
 	}
 
 	mutex_lock(&info->port.mutex);
-	info->port.tty->low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
+	info->port.low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 
 	spin_lock_irqsave(&info->netlock, flags);
 	if (info->netcount) {
@@ -786,7 +785,7 @@ static void set_termios(struct tty_struct *tty, struct ktermios *old_termios)
 	/* Handle transition to B0 status */
 	if (old_termios->c_cflag & CBAUD &&
 	    !(tty->termios.c_cflag & CBAUD)) {
-		info->signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
 		spin_lock_irqsave(&info->lock,flags);
 		set_signals(info);
 		spin_unlock_irqrestore(&info->lock,flags);
@@ -1561,8 +1560,8 @@ static int hdlcdev_open(struct net_device *dev)
 		return rc;
 	}
 
-	/* assert DTR and RTS, apply hardware settings */
-	info->signals |= SerialSignal_RTS + SerialSignal_DTR;
+	/* assert RTS and DTR, apply hardware settings */
+	info->signals |= SerialSignal_RTS | SerialSignal_DTR;
 	program_hw(info);
 
 	/* enable network layer transmit */
@@ -1855,7 +1854,6 @@ static void hdlcdev_exit(struct slgt_info *info)
  */
 static void rx_async(struct slgt_info *info)
 {
- 	struct tty_struct *tty = info->port.tty;
  	struct mgsl_icount *icount = &info->icount;
 	unsigned int start, end;
 	unsigned char *p;
@@ -1894,10 +1892,8 @@ static void rx_async(struct slgt_info *info)
 				else if (status & BIT0)
 					stat = TTY_FRAME;
 			}
-			if (tty) {
-				tty_insert_flip_char(tty, ch, stat);
-				chars++;
-			}
+			tty_insert_flip_char(&info->port, ch, stat);
+			chars++;
 		}
 
 		if (i < count) {
@@ -1918,8 +1914,8 @@ static void rx_async(struct slgt_info *info)
 			break;
 	}
 
-	if (tty && chars)
-		tty_flip_buffer_push(tty);
+	if (chars)
+		tty_flip_buffer_push(&info->port);
 }
 
 /*
@@ -1961,8 +1957,6 @@ static void bh_handler(struct work_struct *work)
 	struct slgt_info *info = container_of(work, struct slgt_info, task);
 	int action;
 
-	if (!info)
-		return;
 	info->bh_running = true;
 
 	while((action = bh_action(info))) {
@@ -2183,7 +2177,7 @@ static void isr_serial(struct slgt_info *info)
 			if (info->port.tty) {
 				if (!(status & info->ignore_status_mask)) {
 					if (info->read_status_mask & MASK_BREAK) {
-						tty_insert_flip_char(info->port.tty, 0, TTY_BREAK);
+						tty_insert_flip_char(&info->port, 0, TTY_BREAK);
 						if (info->port.flags & ASYNC_SAK)
 							do_SAK(info->port.tty);
 					}
@@ -2494,7 +2488,7 @@ static void shutdown(struct slgt_info *info)
 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
 
  	if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
- 		info->signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
+		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
 		set_signals(info);
 	}
 
@@ -2554,12 +2548,12 @@ static void change_params(struct slgt_info *info)
 
 	cflag = info->port.tty->termios.c_cflag;
 
-	/* if B0 rate (hangup) specified then negate DTR and RTS */
-	/* otherwise assert DTR and RTS */
+	/* if B0 rate (hangup) specified then negate RTS and DTR */
+	/* otherwise assert RTS and DTR */
  	if (cflag & CBAUD)
-		info->signals |= SerialSignal_RTS + SerialSignal_DTR;
+		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
 	else
-		info->signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
 
 	/* byte size and parity */
 
@@ -3262,9 +3256,9 @@ static void dtr_rts(struct tty_port *port, int on)
 
 	spin_lock_irqsave(&info->lock,flags);
 	if (on)
-		info->signals |= SerialSignal_RTS + SerialSignal_DTR;
+		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
 	else
-		info->signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
  	set_signals(info);
 	spin_unlock_irqrestore(&info->lock,flags);
 }
@@ -3355,11 +3349,24 @@ static int block_til_ready(struct tty_struct *tty, struct file *filp,
 	return retval;
 }
 
+/*
+ * allocate buffers used for calling line discipline receive_buf
+ * directly in synchronous mode
+ * note: add 5 bytes to max frame size to allow appending
+ * 32-bit CRC and status byte when configured to do so
+ */
 static int alloc_tmp_rbuf(struct slgt_info *info)
 {
 	info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
 	if (info->tmp_rbuf == NULL)
 		return -ENOMEM;
+	/* unused flag buffer to satisfy receive_buf calling interface */
+	info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
+	if (!info->flag_buf) {
+		kfree(info->tmp_rbuf);
+		info->tmp_rbuf = NULL;
+		return -ENOMEM;
+	}
 	return 0;
 }
 
@@ -3367,6 +3374,8 @@ static void free_tmp_rbuf(struct slgt_info *info)
 {
 	kfree(info->tmp_rbuf);
 	info->tmp_rbuf = NULL;
+	kfree(info->flag_buf);
+	info->flag_buf = NULL;
 }
 
 /*
@@ -4110,7 +4119,7 @@ static void reset_port(struct slgt_info *info)
 	tx_stop(info);
 	rx_stop(info);
 
-	info->signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
+	info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
 	set_signals(info);
 
 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
@@ -4537,8 +4546,8 @@ static void get_signals(struct slgt_info *info)
 {
 	unsigned short status = rd_reg16(info, SSR);
 
-	/* clear all serial signals except DTR and RTS */
-	info->signals &= SerialSignal_DTR + SerialSignal_RTS;
+	/* clear all serial signals except RTS and DTR */
+	info->signals &= SerialSignal_RTS | SerialSignal_DTR;
 
 	if (status & BIT3)
 		info->signals |= SerialSignal_DSR;
diff --git a/drivers/tty/synclinkmp.c b/drivers/tty/synclinkmp.c
index fd43fb6f7ce..6d5780cf1d5 100644
--- a/drivers/tty/synclinkmp.c
+++ b/drivers/tty/synclinkmp.c
@@ -262,8 +262,7 @@ typedef struct _synclinkmp_info {
 	bool sca_statctrl_requested;
 
 	u32 misc_ctrl_value;
-	char flag_buf[MAX_ASYNC_BUFFER_SIZE];
-	char char_buf[MAX_ASYNC_BUFFER_SIZE];
+	char *flag_buf;
 	bool drop_rts_on_tx_done;
 
 	struct	_input_signal_events	input_signal_events;
@@ -762,7 +761,7 @@ static int open(struct tty_struct *tty, struct file *filp)
 		goto cleanup;
 	}
 
-	info->port.tty->low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
+	info->port.low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 
 	spin_lock_irqsave(&info->netlock, flags);
 	if (info->netcount) {
@@ -883,7 +882,7 @@ static void set_termios(struct tty_struct *tty, struct ktermios *old_termios)
 	/* Handle transition to B0 status */
 	if (old_termios->c_cflag & CBAUD &&
 	    !(tty->termios.c_cflag & CBAUD)) {
-		info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
 		spin_lock_irqsave(&info->lock,flags);
 	 	set_signals(info);
 		spin_unlock_irqrestore(&info->lock,flags);
@@ -1677,8 +1676,8 @@ static int hdlcdev_open(struct net_device *dev)
 		return rc;
 	}
 
-	/* assert DTR and RTS, apply hardware settings */
-	info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
+	/* assert RTS and DTR, apply hardware settings */
+	info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
 	program_hw(info);
 
 	/* enable network layer transmit */
@@ -2008,9 +2007,6 @@ static void bh_handler(struct work_struct *work)
 	SLMP_INFO *info = container_of(work, SLMP_INFO, task);
 	int action;
 
-	if (!info)
-		return;
-
 	if ( debug_level >= DEBUG_LEVEL_BH )
 		printk( "%s(%d):%s bh_handler() entry\n",
 			__FILE__,__LINE__,info->device_name);
@@ -2132,13 +2128,11 @@ static void isr_rxint(SLMP_INFO * info)
 			/* process break detection if tty control
 			 * is not set to ignore it
 			 */
-			if ( tty ) {
-				if (!(status & info->ignore_status_mask1)) {
-					if (info->read_status_mask1 & BRKD) {
-						tty_insert_flip_char(tty, 0, TTY_BREAK);
-						if (info->port.flags & ASYNC_SAK)
-							do_SAK(tty);
-					}
+			if (!(status & info->ignore_status_mask1)) {
+				if (info->read_status_mask1 & BRKD) {
+					tty_insert_flip_char(&info->port, 0, TTY_BREAK);
+					if (tty && (info->port.flags & ASYNC_SAK))
+						do_SAK(tty);
 				}
 			}
 		}
@@ -2170,7 +2164,6 @@ static void isr_rxrdy(SLMP_INFO * info)
 {
 	u16 status;
 	unsigned char DataByte;
- 	struct tty_struct *tty = info->port.tty;
  	struct	mgsl_icount *icount = &info->icount;
 
 	if ( debug_level >= DEBUG_LEVEL_ISR )
@@ -2203,26 +2196,22 @@ static void isr_rxrdy(SLMP_INFO * info)
 
 			status &= info->read_status_mask2;
 
-			if ( tty ) {
-				if (status & PE)
-					flag = TTY_PARITY;
-				else if (status & FRME)
-					flag = TTY_FRAME;
-				if (status & OVRN) {
-					/* Overrun is special, since it's
-					 * reported immediately, and doesn't
-					 * affect the current character
-					 */
-					over = true;
-				}
+			if (status & PE)
+				flag = TTY_PARITY;
+			else if (status & FRME)
+				flag = TTY_FRAME;
+			if (status & OVRN) {
+				/* Overrun is special, since it's
+				 * reported immediately, and doesn't
+				 * affect the current character
+				 */
+				over = true;
 			}
 		}	/* end of if (error) */
 
-		if ( tty ) {
-			tty_insert_flip_char(tty, DataByte, flag);
-			if (over)
-				tty_insert_flip_char(tty, 0, TTY_OVERRUN);
-		}
+		tty_insert_flip_char(&info->port, DataByte, flag);
+		if (over)
+			tty_insert_flip_char(&info->port, 0, TTY_OVERRUN);
 	}
 
 	if ( debug_level >= DEBUG_LEVEL_ISR ) {
@@ -2232,8 +2221,7 @@ static void isr_rxrdy(SLMP_INFO * info)
 			icount->frame,icount->overrun);
 	}
 
-	if ( tty )
-		tty_flip_buffer_push(tty);
+	tty_flip_buffer_push(&info->port);
 }
 
 static void isr_txeom(SLMP_INFO * info, unsigned char status)
@@ -2718,7 +2706,7 @@ static void shutdown(SLMP_INFO * info)
 	reset_port(info);
 
  	if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
- 		info->serial_signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
 		set_signals(info);
 	}
 
@@ -2780,12 +2768,12 @@ static void change_params(SLMP_INFO *info)
 
 	cflag = info->port.tty->termios.c_cflag;
 
-	/* if B0 rate (hangup) specified then negate DTR and RTS */
-	/* otherwise assert DTR and RTS */
+	/* if B0 rate (hangup) specified then negate RTS and DTR */
+	/* otherwise assert RTS and DTR */
  	if (cflag & CBAUD)
-		info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
+		info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
 	else
-		info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
 
 	/* byte size and parity */
 
@@ -3224,12 +3212,12 @@ static int tiocmget(struct tty_struct *tty)
  	get_signals(info);
 	spin_unlock_irqrestore(&info->lock,flags);
 
-	result = ((info->serial_signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
-		((info->serial_signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
-		((info->serial_signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
-		((info->serial_signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
-		((info->serial_signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
-		((info->serial_signals & SerialSignal_CTS) ? TIOCM_CTS:0);
+	result = ((info->serial_signals & SerialSignal_RTS) ? TIOCM_RTS : 0) |
+		 ((info->serial_signals & SerialSignal_DTR) ? TIOCM_DTR : 0) |
+		 ((info->serial_signals & SerialSignal_DCD) ? TIOCM_CAR : 0) |
+		 ((info->serial_signals & SerialSignal_RI)  ? TIOCM_RNG : 0) |
+		 ((info->serial_signals & SerialSignal_DSR) ? TIOCM_DSR : 0) |
+		 ((info->serial_signals & SerialSignal_CTS) ? TIOCM_CTS : 0);
 
 	if (debug_level >= DEBUG_LEVEL_INFO)
 		printk("%s(%d):%s tiocmget() value=%08X\n",
@@ -3284,9 +3272,9 @@ static void dtr_rts(struct tty_port *port, int on)
 
 	spin_lock_irqsave(&info->lock,flags);
 	if (on)
-		info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
+		info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
 	else
-		info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
  	set_signals(info);
 	spin_unlock_irqrestore(&info->lock,flags);
 }
@@ -3553,6 +3541,13 @@ static int alloc_tmp_rx_buf(SLMP_INFO *info)
 	info->tmp_rx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
 	if (info->tmp_rx_buf == NULL)
 		return -ENOMEM;
+	/* unused flag buffer to satisfy receive_buf calling interface */
+	info->flag_buf = kzalloc(info->max_frame_size, GFP_KERNEL);
+	if (!info->flag_buf) {
+		kfree(info->tmp_rx_buf);
+		info->tmp_rx_buf = NULL;
+		return -ENOMEM;
+	}
 	return 0;
 }
 
@@ -3560,6 +3555,8 @@ static void free_tmp_rx_buf(SLMP_INFO *info)
 {
 	kfree(info->tmp_rx_buf);
 	info->tmp_rx_buf = NULL;
+	kfree(info->flag_buf);
+	info->flag_buf = NULL;
 }
 
 static int claim_resources(SLMP_INFO *info)
@@ -4357,7 +4354,7 @@ static void reset_port(SLMP_INFO *info)
 		tx_stop(info);
 		rx_stop(info);
 
-		info->serial_signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
 		set_signals(info);
 
 		/* disable all port interrupts */
@@ -4753,8 +4750,8 @@ static void get_signals(SLMP_INFO *info)
 	u16 gpstatus = read_status_reg(info);
 	u16 testbit;
 
-	/* clear all serial signals except DTR and RTS */
-	info->serial_signals &= SerialSignal_DTR + SerialSignal_RTS;
+	/* clear all serial signals except RTS and DTR */
+	info->serial_signals &= SerialSignal_RTS | SerialSignal_DTR;
 
 	/* set serial signal bits to reflect MISR */
 
@@ -4773,7 +4770,7 @@ static void get_signals(SLMP_INFO *info)
 		info->serial_signals |= SerialSignal_DSR;
 }
 
-/* Set the state of DTR and RTS based on contents of
+/* Set the state of RTS and DTR based on contents of
  * serial_signals member of device context.
  */
 static void set_signals(SLMP_INFO *info)
diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c
index 45d916198f7..bb119934e76 100644
--- a/drivers/tty/tty_buffer.c
+++ b/drivers/tty/tty_buffer.c
@@ -16,6 +16,7 @@
 #include <linux/bitops.h>
 #include <linux/delay.h>
 #include <linux/module.h>
+#include <linux/ratelimit.h>
 
 /**
  *	tty_buffer_free_all		-	free buffers used by a tty
@@ -119,11 +120,14 @@ static void __tty_buffer_flush(struct tty_port *port)
 	struct tty_bufhead *buf = &port->buf;
 	struct tty_buffer *thead;
 
-	while ((thead = buf->head) != NULL) {
-		buf->head = thead->next;
-		tty_buffer_free(port, thead);
+	if (unlikely(buf->head == NULL))
+		return;
+	while ((thead = buf->head->next) != NULL) {
+		tty_buffer_free(port, buf->head);
+		buf->head = thead;
 	}
-	buf->tail = NULL;
+	WARN_ON(buf->head != buf->tail);
+	buf->head->read = buf->head->commit;
 }
 
 /**
@@ -194,19 +198,22 @@ static struct tty_buffer *tty_buffer_find(struct tty_port *port, size_t size)
 	   have queued and recycle that ? */
 }
 /**
- *	__tty_buffer_request_room		-	grow tty buffer if needed
+ *	tty_buffer_request_room		-	grow tty buffer if needed
  *	@tty: tty structure
  *	@size: size desired
  *
  *	Make at least size bytes of linear space available for the tty
  *	buffer. If we fail return the size we managed to find.
- *      Locking: Caller must hold port->buf.lock
+ *
+ *	Locking: Takes port->buf.lock
  */
-static int __tty_buffer_request_room(struct tty_port *port, size_t size)
+int tty_buffer_request_room(struct tty_port *port, size_t size)
 {
 	struct tty_bufhead *buf = &port->buf;
 	struct tty_buffer *b, *n;
 	int left;
+	unsigned long flags;
+	spin_lock_irqsave(&buf->lock, flags);
 	/* OPTIMISATION: We could keep a per tty "zero" sized buffer to
 	   remove this conditional if its worth it. This would be invisible
 	   to the callers */
@@ -228,37 +235,14 @@ static int __tty_buffer_request_room(struct tty_port *port, size_t size)
 		} else
 			size = left;
 	}
-
+	spin_unlock_irqrestore(&buf->lock, flags);
 	return size;
 }
-
-
-/**
- *	tty_buffer_request_room		-	grow tty buffer if needed
- *	@tty: tty structure
- *	@size: size desired
- *
- *	Make at least size bytes of linear space available for the tty
- *	buffer. If we fail return the size we managed to find.
- *
- *	Locking: Takes port->buf.lock
- */
-int tty_buffer_request_room(struct tty_struct *tty, size_t size)
-{
-	struct tty_port *port = tty->port;
-	unsigned long flags;
-	int length;
-
-	spin_lock_irqsave(&port->buf.lock, flags);
-	length = __tty_buffer_request_room(port, size);
-	spin_unlock_irqrestore(&port->buf.lock, flags);
-	return length;
-}
 EXPORT_SYMBOL_GPL(tty_buffer_request_room);
 
 /**
  *	tty_insert_flip_string_fixed_flag - Add characters to the tty buffer
- *	@tty: tty structure
+ *	@port: tty port
  *	@chars: characters
  *	@flag: flag value for each character
  *	@size: size
@@ -269,29 +253,21 @@ EXPORT_SYMBOL_GPL(tty_buffer_request_room);
  *	Locking: Called functions may take port->buf.lock
  */
 
-int tty_insert_flip_string_fixed_flag(struct tty_struct *tty,
+int tty_insert_flip_string_fixed_flag(struct tty_port *port,
 		const unsigned char *chars, char flag, size_t size)
 {
-	struct tty_bufhead *buf = &tty->port->buf;
 	int copied = 0;
 	do {
 		int goal = min_t(size_t, size - copied, TTY_BUFFER_PAGE);
-		int space;
-		unsigned long flags;
-		struct tty_buffer *tb;
-
-		spin_lock_irqsave(&buf->lock, flags);
-		space = __tty_buffer_request_room(tty->port, goal);
-		tb = buf->tail;
+		int space = tty_buffer_request_room(port, goal);
+		struct tty_buffer *tb = port->buf.tail;
 		/* If there is no space then tb may be NULL */
 		if (unlikely(space == 0)) {
-			spin_unlock_irqrestore(&buf->lock, flags);
 			break;
 		}
 		memcpy(tb->char_buf_ptr + tb->used, chars, space);
 		memset(tb->flag_buf_ptr + tb->used, flag, space);
 		tb->used += space;
-		spin_unlock_irqrestore(&buf->lock, flags);
 		copied += space;
 		chars += space;
 		/* There is a small chance that we need to split the data over
@@ -303,7 +279,7 @@ EXPORT_SYMBOL(tty_insert_flip_string_fixed_flag);
 
 /**
  *	tty_insert_flip_string_flags	-	Add characters to the tty buffer
- *	@tty: tty structure
+ *	@port: tty port
  *	@chars: characters
  *	@flags: flag bytes
  *	@size: size
@@ -315,29 +291,21 @@ EXPORT_SYMBOL(tty_insert_flip_string_fixed_flag);
  *	Locking: Called functions may take port->buf.lock
  */
 
-int tty_insert_flip_string_flags(struct tty_struct *tty,
+int tty_insert_flip_string_flags(struct tty_port *port,
 		const unsigned char *chars, const char *flags, size_t size)
 {
-	struct tty_bufhead *buf = &tty->port->buf;
 	int copied = 0;
 	do {
 		int goal = min_t(size_t, size - copied, TTY_BUFFER_PAGE);
-		int space;
-		unsigned long __flags;
-		struct tty_buffer *tb;
-
-		spin_lock_irqsave(&buf->lock, __flags);
-		space = __tty_buffer_request_room(tty->port, goal);
-		tb = buf->tail;
+		int space = tty_buffer_request_room(port, goal);
+		struct tty_buffer *tb = port->buf.tail;
 		/* If there is no space then tb may be NULL */
 		if (unlikely(space == 0)) {
-			spin_unlock_irqrestore(&buf->lock, __flags);
 			break;
 		}
 		memcpy(tb->char_buf_ptr + tb->used, chars, space);
 		memcpy(tb->flag_buf_ptr + tb->used, flags, space);
 		tb->used += space;
-		spin_unlock_irqrestore(&buf->lock, __flags);
 		copied += space;
 		chars += space;
 		flags += space;
@@ -350,7 +318,7 @@ EXPORT_SYMBOL(tty_insert_flip_string_flags);
 
 /**
  *	tty_schedule_flip	-	push characters to ldisc
- *	@tty: tty to push from
+ *	@port: tty port to push from
  *
  *	Takes any pending buffers and transfers their ownership to the
  *	ldisc side of the queue. It then schedules those characters for
@@ -361,11 +329,11 @@ EXPORT_SYMBOL(tty_insert_flip_string_flags);
  *	Locking: Takes port->buf.lock
  */
 
-void tty_schedule_flip(struct tty_struct *tty)
+void tty_schedule_flip(struct tty_port *port)
 {
-	struct tty_bufhead *buf = &tty->port->buf;
+	struct tty_bufhead *buf = &port->buf;
 	unsigned long flags;
-	WARN_ON(tty->low_latency);
+	WARN_ON(port->low_latency);
 
 	spin_lock_irqsave(&buf->lock, flags);
 	if (buf->tail != NULL)
@@ -377,7 +345,7 @@ EXPORT_SYMBOL(tty_schedule_flip);
 
 /**
  *	tty_prepare_flip_string		-	make room for characters
- *	@tty: tty
+ *	@port: tty port
  *	@chars: return pointer for character write area
  *	@size: desired size
  *
@@ -390,31 +358,23 @@ EXPORT_SYMBOL(tty_schedule_flip);
  *	Locking: May call functions taking port->buf.lock
  */
 
-int tty_prepare_flip_string(struct tty_struct *tty, unsigned char **chars,
+int tty_prepare_flip_string(struct tty_port *port, unsigned char **chars,
 		size_t size)
 {
-	struct tty_bufhead *buf = &tty->port->buf;
-	int space;
-	unsigned long flags;
-	struct tty_buffer *tb;
-
-	spin_lock_irqsave(&buf->lock, flags);
-	space = __tty_buffer_request_room(tty->port, size);
-
-	tb = buf->tail;
+	int space = tty_buffer_request_room(port, size);
 	if (likely(space)) {
+		struct tty_buffer *tb = port->buf.tail;
 		*chars = tb->char_buf_ptr + tb->used;
 		memset(tb->flag_buf_ptr + tb->used, TTY_NORMAL, space);
 		tb->used += space;
 	}
-	spin_unlock_irqrestore(&buf->lock, flags);
 	return space;
 }
 EXPORT_SYMBOL_GPL(tty_prepare_flip_string);
 
 /**
  *	tty_prepare_flip_string_flags	-	make room for characters
- *	@tty: tty
+ *	@port: tty port
  *	@chars: return pointer for character write area
  *	@flags: return pointer for status flag write area
  *	@size: desired size
@@ -428,24 +388,16 @@ EXPORT_SYMBOL_GPL(tty_prepare_flip_string);
  *	Locking: May call functions taking port->buf.lock
  */
 
-int tty_prepare_flip_string_flags(struct tty_struct *tty,
+int tty_prepare_flip_string_flags(struct tty_port *port,
 			unsigned char **chars, char **flags, size_t size)
 {
-	struct tty_bufhead *buf = &tty->port->buf;
-	int space;
-	unsigned long __flags;
-	struct tty_buffer *tb;
-
-	spin_lock_irqsave(&buf->lock, __flags);
-	space = __tty_buffer_request_room(tty->port, size);
-
-	tb = buf->tail;
+	int space = tty_buffer_request_room(port, size);
 	if (likely(space)) {
+		struct tty_buffer *tb = port->buf.tail;
 		*chars = tb->char_buf_ptr + tb->used;
 		*flags = tb->flag_buf_ptr + tb->used;
 		tb->used += space;
 	}
-	spin_unlock_irqrestore(&buf->lock, __flags);
 	return space;
 }
 EXPORT_SYMBOL_GPL(tty_prepare_flip_string_flags);
@@ -539,16 +491,17 @@ static void flush_to_ldisc(struct work_struct *work)
  */
 void tty_flush_to_ldisc(struct tty_struct *tty)
 {
-	if (!tty->low_latency)
+	if (!tty->port->low_latency)
 		flush_work(&tty->port->buf.work);
 }
 
 /**
  *	tty_flip_buffer_push	-	terminal
- *	@tty: tty to push
+ *	@port: tty port to push
  *
  *	Queue a push of the terminal flip buffers to the line discipline. This
- *	function must not be called from IRQ context if tty->low_latency is set.
+ *	function must not be called from IRQ context if port->low_latency is
+ *	set.
  *
  *	In the event of the queue being busy for flipping the work will be
  *	held off and retried later.
@@ -556,9 +509,9 @@ void tty_flush_to_ldisc(struct tty_struct *tty)
  *	Locking: tty buffer lock. Driver locks in low latency mode.
  */
 
-void tty_flip_buffer_push(struct tty_struct *tty)
+void tty_flip_buffer_push(struct tty_port *port)
 {
-	struct tty_bufhead *buf = &tty->port->buf;
+	struct tty_bufhead *buf = &port->buf;
 	unsigned long flags;
 
 	spin_lock_irqsave(&buf->lock, flags);
@@ -566,7 +519,7 @@ void tty_flip_buffer_push(struct tty_struct *tty)
 		buf->tail->commit = buf->tail->used;
 	spin_unlock_irqrestore(&buf->lock, flags);
 
-	if (tty->low_latency)
+	if (port->low_latency)
 		flush_to_ldisc(&buf->work);
 	else
 		schedule_work(&buf->work);
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 6b20fd66d4a..60e48a11b66 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -536,7 +536,7 @@ EXPORT_SYMBOL_GPL(tty_wakeup);
  *	__tty_hangup		-	actual handler for hangup events
  *	@work: tty device
  *
- *	This can be called by the "eventd" kernel thread.  That is process
+ *	This can be called by a "kworker" kernel thread.  That is process
  *	synchronous but doesn't hold any locks, so we need to make sure we
  *	have the appropriate locks for what we're doing.
  *
@@ -977,8 +977,7 @@ static ssize_t tty_read(struct file *file, char __user *buf, size_t count,
 	else
 		i = -EIO;
 	tty_ldisc_deref(ld);
-	if (i > 0)
-		inode->i_atime = current_fs_time(inode->i_sb);
+
 	return i;
 }
 
@@ -1079,11 +1078,8 @@ static inline ssize_t do_tty_write(
 			break;
 		cond_resched();
 	}
-	if (written) {
-		struct inode *inode = file->f_path.dentry->d_inode;
-		inode->i_mtime = current_fs_time(inode->i_sb);
+	if (written)
 		ret = written;
-	}
 out:
 	tty_write_unlock(tty);
 	return ret;
diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c
index 8481b29d5b3..d58b92cc187 100644
--- a/drivers/tty/tty_ioctl.c
+++ b/drivers/tty/tty_ioctl.c
@@ -617,7 +617,7 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
 	if (opt & TERMIOS_WAIT) {
 		tty_wait_until_sent(tty, 0);
 		if (signal_pending(current))
-			return -EINTR;
+			return -ERESTARTSYS;
 	}
 
 	tty_set_termios(tty, &tmp_termios);
@@ -684,7 +684,7 @@ static int set_termiox(struct tty_struct *tty, void __user *arg, int opt)
 	if (opt & TERMIOS_WAIT) {
 		tty_wait_until_sent(tty, 0);
 		if (signal_pending(current))
-			return -EINTR;
+			return -ERESTARTSYS;
 	}
 
 	mutex_lock(&tty->termios_mutex);
@@ -1096,12 +1096,16 @@ int tty_perform_flush(struct tty_struct *tty, unsigned long arg)
 	ld = tty_ldisc_ref_wait(tty);
 	switch (arg) {
 	case TCIFLUSH:
-		if (ld && ld->ops->flush_buffer)
+		if (ld && ld->ops->flush_buffer) {
 			ld->ops->flush_buffer(tty);
+			tty_unthrottle(tty);
+		}
 		break;
 	case TCIOFLUSH:
-		if (ld && ld->ops->flush_buffer)
+		if (ld && ld->ops->flush_buffer) {
 			ld->ops->flush_buffer(tty);
+			tty_unthrottle(tty);
+		}
 		/* fall through */
 	case TCOFLUSH:
 		tty_driver_flush_buffer(tty);
diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c
index c5782294e53..d794087c327 100644
--- a/drivers/tty/tty_ldisc.c
+++ b/drivers/tty/tty_ldisc.c
@@ -64,7 +64,9 @@ static void put_ldisc(struct tty_ldisc *ld)
 		return;
 	}
 	raw_spin_unlock_irqrestore(&tty_ldisc_lock, flags);
-	wake_up(&ld->wq_idle);
+
+	if (waitqueue_active(&ld->wq_idle))
+		wake_up(&ld->wq_idle);
 }
 
 /**
@@ -934,17 +936,17 @@ void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty)
 	 * race with the set_ldisc code path.
 	 */
 
-	tty_lock_pair(tty, o_tty);
 	tty_ldisc_halt(tty);
-	tty_ldisc_flush_works(tty);
-	if (o_tty) {
+	if (o_tty)
 		tty_ldisc_halt(o_tty);
+
+	tty_ldisc_flush_works(tty);
+	if (o_tty)
 		tty_ldisc_flush_works(o_tty);
-	}
 
+	tty_lock_pair(tty, o_tty);
 	/* This will need doing differently if we need to lock */
 	tty_ldisc_kill(tty);
-
 	if (o_tty)
 		tty_ldisc_kill(o_tty);
 
diff --git a/drivers/tty/vt/Makefile b/drivers/tty/vt/Makefile
index 14a51c9960d..17ae94cb29f 100644
--- a/drivers/tty/vt/Makefile
+++ b/drivers/tty/vt/Makefile
@@ -27,8 +27,6 @@ $(obj)/defkeymap.o:  $(obj)/defkeymap.c
 ifdef GENERATE_KEYMAP
 
 $(obj)/defkeymap.c: $(obj)/%.c: $(src)/%.map
-	loadkeys --mktable $< > $@.tmp
-	sed -e 's/^static *//' $@.tmp > $@
-	rm $@.tmp
+	loadkeys --mktable $< > $@
 
 endif
diff --git a/drivers/tty/vt/keyboard.c b/drivers/tty/vt/keyboard.c
index 681765baef6..a9af1b9ae16 100644
--- a/drivers/tty/vt/keyboard.c
+++ b/drivers/tty/vt/keyboard.c
@@ -307,26 +307,17 @@ int kbd_rate(struct kbd_repeat *rep)
  */
 static void put_queue(struct vc_data *vc, int ch)
 {
-	struct tty_struct *tty = vc->port.tty;
-
-	if (tty) {
-		tty_insert_flip_char(tty, ch, 0);
-		tty_schedule_flip(tty);
-	}
+	tty_insert_flip_char(&vc->port, ch, 0);
+	tty_schedule_flip(&vc->port);
 }
 
 static void puts_queue(struct vc_data *vc, char *cp)
 {
-	struct tty_struct *tty = vc->port.tty;
-
-	if (!tty)
-		return;
-
 	while (*cp) {
-		tty_insert_flip_char(tty, *cp, 0);
+		tty_insert_flip_char(&vc->port, *cp, 0);
 		cp++;
 	}
-	tty_schedule_flip(tty);
+	tty_schedule_flip(&vc->port);
 }
 
 static void applkey(struct vc_data *vc, int key, char mode)
@@ -582,12 +573,8 @@ static void fn_inc_console(struct vc_data *vc)
 
 static void fn_send_intr(struct vc_data *vc)
 {
-	struct tty_struct *tty = vc->port.tty;
-
-	if (!tty)
-		return;
-	tty_insert_flip_char(tty, 0, TTY_BREAK);
-	tty_schedule_flip(tty);
+	tty_insert_flip_char(&vc->port, 0, TTY_BREAK);
+	tty_schedule_flip(&vc->port);
 }
 
 static void fn_scroll_forw(struct vc_data *vc)
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index 8fd89687d06..1a272803459 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -1333,13 +1333,13 @@ static void csi_m(struct vc_data *vc)
 	update_attr(vc);
 }
 
-static void respond_string(const char *p, struct tty_struct *tty)
+static void respond_string(const char *p, struct tty_port *port)
 {
 	while (*p) {
-		tty_insert_flip_char(tty, *p, 0);
+		tty_insert_flip_char(port, *p, 0);
 		p++;
 	}
-	tty_schedule_flip(tty);
+	tty_schedule_flip(port);
 }
 
 static void cursor_report(struct vc_data *vc, struct tty_struct *tty)
@@ -1347,17 +1347,17 @@ static void cursor_report(struct vc_data *vc, struct tty_struct *tty)
 	char buf[40];
 
 	sprintf(buf, "\033[%d;%dR", vc->vc_y + (vc->vc_decom ? vc->vc_top + 1 : 1), vc->vc_x + 1);
-	respond_string(buf, tty);
+	respond_string(buf, tty->port);
 }
 
 static inline void status_report(struct tty_struct *tty)
 {
-	respond_string("\033[0n", tty);	/* Terminal ok */
+	respond_string("\033[0n", tty->port);	/* Terminal ok */
 }
 
-static inline void respond_ID(struct tty_struct * tty)
+static inline void respond_ID(struct tty_struct *tty)
 {
-	respond_string(VT102ID, tty);
+	respond_string(VT102ID, tty->port);
 }
 
 void mouse_report(struct tty_struct *tty, int butt, int mrx, int mry)
@@ -1366,7 +1366,7 @@ void mouse_report(struct tty_struct *tty, int butt, int mrx, int mry)
 
 	sprintf(buf, "\033[M%c%c%c", (char)(' ' + butt), (char)('!' + mrx),
 		(char)('!' + mry));
-	respond_string(buf, tty);
+	respond_string(buf, tty->port);
 }
 
 /* invoked via ioctl(TIOCLINUX) and through set_selection */