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path: root/drivers/tty/serial/bfin_sport_uart.c
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Diffstat (limited to 'drivers/tty/serial/bfin_sport_uart.c')
-rw-r--r--drivers/tty/serial/bfin_sport_uart.c935
1 files changed, 935 insertions, 0 deletions
diff --git a/drivers/tty/serial/bfin_sport_uart.c b/drivers/tty/serial/bfin_sport_uart.c
new file mode 100644
index 00000000000..e95c524d9d1
--- /dev/null
+++ b/drivers/tty/serial/bfin_sport_uart.c
@@ -0,0 +1,935 @@
+/*
+ * Blackfin On-Chip Sport Emulated UART Driver
+ *
+ * Copyright 2006-2009 Analog Devices Inc.
+ *
+ * Enter bugs at http://blackfin.uclinux.org/
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+/*
+ * This driver and the hardware supported are in term of EE-191 of ADI.
+ * http://www.analog.com/static/imported-files/application_notes/EE191.pdf
+ * This application note describe how to implement a UART on a Sharc DSP,
+ * but this driver is implemented on Blackfin Processor.
+ * Transmit Frame Sync is not used by this driver to transfer data out.
+ */
+
+/* #define DEBUG */
+
+#define DRV_NAME "bfin-sport-uart"
+#define DEVICE_NAME "ttySS"
+#define pr_fmt(fmt) DRV_NAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial_core.h>
+
+#include <asm/bfin_sport.h>
+#include <asm/delay.h>
+#include <asm/portmux.h>
+
+#include "bfin_sport_uart.h"
+
+struct sport_uart_port {
+ struct uart_port port;
+ int err_irq;
+ unsigned short csize;
+ unsigned short rxmask;
+ unsigned short txmask1;
+ unsigned short txmask2;
+ unsigned char stopb;
+/* unsigned char parib; */
+#ifdef CONFIG_SERIAL_BFIN_SPORT_CTSRTS
+ int cts_pin;
+ int rts_pin;
+#endif
+};
+
+static int sport_uart_tx_chars(struct sport_uart_port *up);
+static void sport_stop_tx(struct uart_port *port);
+
+static inline void tx_one_byte(struct sport_uart_port *up, unsigned int value)
+{
+ pr_debug("%s value:%x, mask1=0x%x, mask2=0x%x\n", __func__, value,
+ up->txmask1, up->txmask2);
+
+ /* Place Start and Stop bits */
+ __asm__ __volatile__ (
+ "%[val] <<= 1;"
+ "%[val] = %[val] & %[mask1];"
+ "%[val] = %[val] | %[mask2];"
+ : [val]"+d"(value)
+ : [mask1]"d"(up->txmask1), [mask2]"d"(up->txmask2)
+ : "ASTAT"
+ );
+ pr_debug("%s value:%x\n", __func__, value);
+
+ SPORT_PUT_TX(up, value);
+}
+
+static inline unsigned char rx_one_byte(struct sport_uart_port *up)
+{
+ unsigned int value;
+ unsigned char extract;
+ u32 tmp_mask1, tmp_mask2, tmp_shift, tmp;
+
+ if ((up->csize + up->stopb) > 7)
+ value = SPORT_GET_RX32(up);
+ else
+ value = SPORT_GET_RX(up);
+
+ pr_debug("%s value:%x, cs=%d, mask=0x%x\n", __func__, value,
+ up->csize, up->rxmask);
+
+ /* Extract data */
+ __asm__ __volatile__ (
+ "%[extr] = 0;"
+ "%[mask1] = %[rxmask];"
+ "%[mask2] = 0x0200(Z);"
+ "%[shift] = 0;"
+ "LSETUP(.Lloop_s, .Lloop_e) LC0 = %[lc];"
+ ".Lloop_s:"
+ "%[tmp] = extract(%[val], %[mask1].L)(Z);"
+ "%[tmp] <<= %[shift];"
+ "%[extr] = %[extr] | %[tmp];"
+ "%[mask1] = %[mask1] - %[mask2];"
+ ".Lloop_e:"
+ "%[shift] += 1;"
+ : [extr]"=&d"(extract), [shift]"=&d"(tmp_shift), [tmp]"=&d"(tmp),
+ [mask1]"=&d"(tmp_mask1), [mask2]"=&d"(tmp_mask2)
+ : [val]"d"(value), [rxmask]"d"(up->rxmask), [lc]"a"(up->csize)
+ : "ASTAT", "LB0", "LC0", "LT0"
+ );
+
+ pr_debug(" extract:%x\n", extract);
+ return extract;
+}
+
+static int sport_uart_setup(struct sport_uart_port *up, int size, int baud_rate)
+{
+ int tclkdiv, rclkdiv;
+ unsigned int sclk = get_sclk();
+
+ /* Set TCR1 and TCR2, TFSR is not enabled for uart */
+ SPORT_PUT_TCR1(up, (LATFS | ITFS | TFSR | TLSBIT | ITCLK));
+ SPORT_PUT_TCR2(up, size + 1);
+ pr_debug("%s TCR1:%x, TCR2:%x\n", __func__, SPORT_GET_TCR1(up), SPORT_GET_TCR2(up));
+
+ /* Set RCR1 and RCR2 */
+ SPORT_PUT_RCR1(up, (RCKFE | LARFS | LRFS | RFSR | IRCLK));
+ SPORT_PUT_RCR2(up, (size + 1) * 2 - 1);
+ pr_debug("%s RCR1:%x, RCR2:%x\n", __func__, SPORT_GET_RCR1(up), SPORT_GET_RCR2(up));
+
+ tclkdiv = sclk / (2 * baud_rate) - 1;
+ /* The actual uart baud rate of devices vary between +/-2%. The sport
+ * RX sample rate should be faster than the double of the worst case,
+ * otherwise, wrong data are received. So, set sport RX clock to be
+ * 3% faster.
+ */
+ rclkdiv = sclk / (2 * baud_rate * 2 * 97 / 100) - 1;
+ SPORT_PUT_TCLKDIV(up, tclkdiv);
+ SPORT_PUT_RCLKDIV(up, rclkdiv);
+ SSYNC();
+ pr_debug("%s sclk:%d, baud_rate:%d, tclkdiv:%d, rclkdiv:%d\n",
+ __func__, sclk, baud_rate, tclkdiv, rclkdiv);
+
+ return 0;
+}
+
+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;
+ unsigned int ch;
+
+ spin_lock(&up->port.lock);
+
+ while (SPORT_GET_STAT(up) & RXNE) {
+ ch = rx_one_byte(up);
+ up->port.icount.rx++;
+
+ if (!uart_handle_sysrq_char(&up->port, ch))
+ tty_insert_flip_char(tty, ch, TTY_NORMAL);
+ }
+ tty_flip_buffer_push(tty);
+
+ spin_unlock(&up->port.lock);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t sport_uart_tx_irq(int irq, void *dev_id)
+{
+ struct sport_uart_port *up = dev_id;
+
+ spin_lock(&up->port.lock);
+ sport_uart_tx_chars(up);
+ spin_unlock(&up->port.lock);
+
+ return IRQ_HANDLED;
+}
+
+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);
+
+ /* Overflow in RX FIFO */
+ if (stat & ROVF) {
+ up->port.icount.overrun++;
+ tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+ SPORT_PUT_STAT(up, ROVF); /* Clear ROVF bit */
+ }
+ /* These should not happen */
+ if (stat & (TOVF | TUVF | RUVF)) {
+ pr_err("SPORT Error:%s %s %s\n",
+ (stat & TOVF) ? "TX overflow" : "",
+ (stat & TUVF) ? "TX underflow" : "",
+ (stat & RUVF) ? "RX underflow" : "");
+ SPORT_PUT_TCR1(up, SPORT_GET_TCR1(up) & ~TSPEN);
+ SPORT_PUT_RCR1(up, SPORT_GET_RCR1(up) & ~RSPEN);
+ }
+ SSYNC();
+
+ spin_unlock(&up->port.lock);
+ return IRQ_HANDLED;
+}
+
+#ifdef CONFIG_SERIAL_BFIN_SPORT_CTSRTS
+static unsigned int sport_get_mctrl(struct uart_port *port)
+{
+ struct sport_uart_port *up = (struct sport_uart_port *)port;
+ if (up->cts_pin < 0)
+ return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
+
+ /* CTS PIN is negative assertive. */
+ if (SPORT_UART_GET_CTS(up))
+ return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
+ else
+ return TIOCM_DSR | TIOCM_CAR;
+}
+
+static void sport_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ struct sport_uart_port *up = (struct sport_uart_port *)port;
+ if (up->rts_pin < 0)
+ return;
+
+ /* RTS PIN is negative assertive. */
+ if (mctrl & TIOCM_RTS)
+ SPORT_UART_ENABLE_RTS(up);
+ else
+ SPORT_UART_DISABLE_RTS(up);
+}
+
+/*
+ * Handle any change of modem status signal.
+ */
+static irqreturn_t sport_mctrl_cts_int(int irq, void *dev_id)
+{
+ struct sport_uart_port *up = (struct sport_uart_port *)dev_id;
+ unsigned int status;
+
+ status = sport_get_mctrl(&up->port);
+ uart_handle_cts_change(&up->port, status & TIOCM_CTS);
+
+ return IRQ_HANDLED;
+}
+#else
+static unsigned int sport_get_mctrl(struct uart_port *port)
+{
+ pr_debug("%s enter\n", __func__);
+ return TIOCM_CTS | TIOCM_CD | TIOCM_DSR;
+}
+
+static void sport_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ pr_debug("%s enter\n", __func__);
+}
+#endif
+
+/* Reqeust IRQ, Setup clock */
+static int sport_startup(struct uart_port *port)
+{
+ struct sport_uart_port *up = (struct sport_uart_port *)port;
+ int ret;
+
+ pr_debug("%s enter\n", __func__);
+ ret = request_irq(up->port.irq, sport_uart_rx_irq, 0,
+ "SPORT_UART_RX", up);
+ if (ret) {
+ dev_err(port->dev, "unable to request SPORT RX interrupt\n");
+ return ret;
+ }
+
+ ret = request_irq(up->port.irq+1, sport_uart_tx_irq, 0,
+ "SPORT_UART_TX", up);
+ if (ret) {
+ dev_err(port->dev, "unable to request SPORT TX interrupt\n");
+ goto fail1;
+ }
+
+ ret = request_irq(up->err_irq, sport_uart_err_irq, 0,
+ "SPORT_UART_STATUS", up);
+ if (ret) {
+ dev_err(port->dev, "unable to request SPORT status interrupt\n");
+ goto fail2;
+ }
+
+#ifdef CONFIG_SERIAL_BFIN_SPORT_CTSRTS
+ if (up->cts_pin >= 0) {
+ if (request_irq(gpio_to_irq(up->cts_pin),
+ sport_mctrl_cts_int,
+ IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
+ IRQF_DISABLED, "BFIN_SPORT_UART_CTS", up)) {
+ up->cts_pin = -1;
+ dev_info(port->dev, "Unable to attach BlackFin UART \
+ over SPORT CTS interrupt. So, disable it.\n");
+ }
+ }
+ if (up->rts_pin >= 0)
+ gpio_direction_output(up->rts_pin, 0);
+#endif
+
+ return 0;
+ fail2:
+ free_irq(up->port.irq+1, up);
+ fail1:
+ free_irq(up->port.irq, up);
+
+ return ret;
+}
+
+/*
+ * sport_uart_tx_chars
+ *
+ * ret 1 means need to enable sport.
+ * ret 0 means do nothing.
+ */
+static int sport_uart_tx_chars(struct sport_uart_port *up)
+{
+ struct circ_buf *xmit = &up->port.state->xmit;
+
+ if (SPORT_GET_STAT(up) & TXF)
+ return 0;
+
+ if (up->port.x_char) {
+ tx_one_byte(up, up->port.x_char);
+ up->port.icount.tx++;
+ up->port.x_char = 0;
+ return 1;
+ }
+
+ if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
+ /* The waiting loop to stop SPORT TX from TX interrupt is
+ * too long. This may block SPORT RX interrupts and cause
+ * RX FIFO overflow. So, do stop sport TX only after the last
+ * char in TX FIFO is moved into the shift register.
+ */
+ if (SPORT_GET_STAT(up) & TXHRE)
+ sport_stop_tx(&up->port);
+ return 0;
+ }
+
+ while(!(SPORT_GET_STAT(up) & TXF) && !uart_circ_empty(xmit)) {
+ tx_one_byte(up, xmit->buf[xmit->tail]);
+ 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);
+
+ return 1;
+}
+
+static unsigned int sport_tx_empty(struct uart_port *port)
+{
+ struct sport_uart_port *up = (struct sport_uart_port *)port;
+ unsigned int stat;
+
+ stat = SPORT_GET_STAT(up);
+ pr_debug("%s stat:%04x\n", __func__, stat);
+ if (stat & TXHRE) {
+ return TIOCSER_TEMT;
+ } else
+ return 0;
+}
+
+static void sport_stop_tx(struct uart_port *port)
+{
+ struct sport_uart_port *up = (struct sport_uart_port *)port;
+
+ pr_debug("%s enter\n", __func__);
+
+ if (!(SPORT_GET_TCR1(up) & TSPEN))
+ return;
+
+ /* Although the hold register is empty, last byte is still in shift
+ * register and not sent out yet. So, put a dummy data into TX FIFO.
+ * Then, sport tx stops when last byte is shift out and the dummy
+ * data is moved into the shift register.
+ */
+ SPORT_PUT_TX(up, 0xffff);
+ while (!(SPORT_GET_STAT(up) & TXHRE))
+ cpu_relax();
+
+ SPORT_PUT_TCR1(up, (SPORT_GET_TCR1(up) & ~TSPEN));
+ SSYNC();
+
+ return;
+}
+
+static void sport_start_tx(struct uart_port *port)
+{
+ struct sport_uart_port *up = (struct sport_uart_port *)port;
+
+ pr_debug("%s enter\n", __func__);
+
+ /* Write data into SPORT FIFO before enable SPROT to transmit */
+ if (sport_uart_tx_chars(up)) {
+ /* Enable transmit, then an interrupt will generated */
+ SPORT_PUT_TCR1(up, (SPORT_GET_TCR1(up) | TSPEN));
+ SSYNC();
+ }
+
+ pr_debug("%s exit\n", __func__);
+}
+
+static void sport_stop_rx(struct uart_port *port)
+{
+ struct sport_uart_port *up = (struct sport_uart_port *)port;
+
+ pr_debug("%s enter\n", __func__);
+ /* Disable sport to stop rx */
+ SPORT_PUT_RCR1(up, (SPORT_GET_RCR1(up) & ~RSPEN));
+ SSYNC();
+}
+
+static void sport_enable_ms(struct uart_port *port)
+{
+ pr_debug("%s enter\n", __func__);
+}
+
+static void sport_break_ctl(struct uart_port *port, int break_state)
+{
+ pr_debug("%s enter\n", __func__);
+}
+
+static void sport_shutdown(struct uart_port *port)
+{
+ struct sport_uart_port *up = (struct sport_uart_port *)port;
+
+ dev_dbg(port->dev, "%s enter\n", __func__);
+
+ /* Disable sport */
+ SPORT_PUT_TCR1(up, (SPORT_GET_TCR1(up) & ~TSPEN));
+ SPORT_PUT_RCR1(up, (SPORT_GET_RCR1(up) & ~RSPEN));
+ SSYNC();
+
+ free_irq(up->port.irq, up);
+ free_irq(up->port.irq+1, up);
+ free_irq(up->err_irq, up);
+#ifdef CONFIG_SERIAL_BFIN_SPORT_CTSRTS
+ if (up->cts_pin >= 0)
+ free_irq(gpio_to_irq(up->cts_pin), up);
+#endif
+}
+
+static const char *sport_type(struct uart_port *port)
+{
+ struct sport_uart_port *up = (struct sport_uart_port *)port;
+
+ pr_debug("%s enter\n", __func__);
+ return up->port.type == PORT_BFIN_SPORT ? "BFIN-SPORT-UART" : NULL;
+}
+
+static void sport_release_port(struct uart_port *port)
+{
+ pr_debug("%s enter\n", __func__);
+}
+
+static int sport_request_port(struct uart_port *port)
+{
+ pr_debug("%s enter\n", __func__);
+ return 0;
+}
+
+static void sport_config_port(struct uart_port *port, int flags)
+{
+ struct sport_uart_port *up = (struct sport_uart_port *)port;
+
+ pr_debug("%s enter\n", __func__);
+ up->port.type = PORT_BFIN_SPORT;
+}
+
+static int sport_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+ pr_debug("%s enter\n", __func__);
+ return 0;
+}
+
+static void sport_set_termios(struct uart_port *port,
+ struct ktermios *termios, struct ktermios *old)
+{
+ struct sport_uart_port *up = (struct sport_uart_port *)port;
+ unsigned long flags;
+ int i;
+
+ pr_debug("%s enter, c_cflag:%08x\n", __func__, termios->c_cflag);
+
+ switch (termios->c_cflag & CSIZE) {
+ case CS8:
+ up->csize = 8;
+ break;
+ case CS7:
+ up->csize = 7;
+ break;
+ case CS6:
+ up->csize = 6;
+ break;
+ case CS5:
+ up->csize = 5;
+ break;
+ default:
+ pr_warning("requested word length not supported\n");
+ }
+
+ if (termios->c_cflag & CSTOPB) {
+ up->stopb = 1;
+ }
+ if (termios->c_cflag & PARENB) {
+ pr_warning("PAREN bits is not supported yet\n");
+ /* up->parib = 1; */
+ }
+
+ spin_lock_irqsave(&up->port.lock, flags);
+
+ port->read_status_mask = 0;
+
+ /*
+ * Characters to ignore
+ */
+ port->ignore_status_mask = 0;
+
+ /* RX extract mask */
+ up->rxmask = 0x01 | (((up->csize + up->stopb) * 2 - 1) << 0x8);
+ /* TX masks, 8 bit data and 1 bit stop for example:
+ * mask1 = b#0111111110
+ * mask2 = b#1000000000
+ */
+ for (i = 0, up->txmask1 = 0; i < up->csize; i++)
+ up->txmask1 |= (1<<i);
+ up->txmask2 = (1<<i);
+ if (up->stopb) {
+ ++i;
+ up->txmask2 |= (1<<i);
+ }
+ up->txmask1 <<= 1;
+ up->txmask2 <<= 1;
+ /* uart baud rate */
+ port->uartclk = uart_get_baud_rate(port, termios, old, 0, get_sclk()/16);
+
+ /* Disable UART */
+ SPORT_PUT_TCR1(up, SPORT_GET_TCR1(up) & ~TSPEN);
+ SPORT_PUT_RCR1(up, SPORT_GET_RCR1(up) & ~RSPEN);
+
+ sport_uart_setup(up, up->csize + up->stopb, port->uartclk);
+
+ /* driver TX line high after config, one dummy data is
+ * necessary to stop sport after shift one byte
+ */
+ SPORT_PUT_TX(up, 0xffff);
+ SPORT_PUT_TX(up, 0xffff);
+ SPORT_PUT_TCR1(up, (SPORT_GET_TCR1(up) | TSPEN));
+ SSYNC();
+ while (!(SPORT_GET_STAT(up) & TXHRE))
+ cpu_relax();
+ SPORT_PUT_TCR1(up, SPORT_GET_TCR1(up) & ~TSPEN);
+ SSYNC();
+
+ /* Port speed changed, update the per-port timeout. */
+ uart_update_timeout(port, termios->c_cflag, port->uartclk);
+
+ /* Enable sport rx */
+ SPORT_PUT_RCR1(up, SPORT_GET_RCR1(up) | RSPEN);
+ SSYNC();
+
+ spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+struct uart_ops sport_uart_ops = {
+ .tx_empty = sport_tx_empty,
+ .set_mctrl = sport_set_mctrl,
+ .get_mctrl = sport_get_mctrl,
+ .stop_tx = sport_stop_tx,
+ .start_tx = sport_start_tx,
+ .stop_rx = sport_stop_rx,
+ .enable_ms = sport_enable_ms,
+ .break_ctl = sport_break_ctl,
+ .startup = sport_startup,
+ .shutdown = sport_shutdown,
+ .set_termios = sport_set_termios,
+ .type = sport_type,
+ .release_port = sport_release_port,
+ .request_port = sport_request_port,
+ .config_port = sport_config_port,
+ .verify_port = sport_verify_port,
+};
+
+#define BFIN_SPORT_UART_MAX_PORTS 4
+
+static struct sport_uart_port *bfin_sport_uart_ports[BFIN_SPORT_UART_MAX_PORTS];
+
+#ifdef CONFIG_SERIAL_BFIN_SPORT_CONSOLE
+#define CLASS_BFIN_SPORT_CONSOLE "bfin-sport-console"
+
+static int __init
+sport_uart_console_setup(struct console *co, char *options)
+{
+ struct sport_uart_port *up;
+ int baud = 57600;
+ int bits = 8;
+ int parity = 'n';
+# ifdef CONFIG_SERIAL_BFIN_SPORT_CTSRTS
+ int flow = 'r';
+# else
+ int flow = 'n';
+# endif
+
+ /* Check whether an invalid uart number has been specified */
+ if (co->index < 0 || co->index >= BFIN_SPORT_UART_MAX_PORTS)
+ return -ENODEV;
+
+ up = bfin_sport_uart_ports[co->index];
+ if (!up)
+ return -ENODEV;
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+
+ return uart_set_options(&up->port, co, baud, parity, bits, flow);
+}
+
+static void sport_uart_console_putchar(struct uart_port *port, int ch)
+{
+ struct sport_uart_port *up = (struct sport_uart_port *)port;
+
+ while (SPORT_GET_STAT(up) & TXF)
+ barrier();
+
+ tx_one_byte(up, ch);
+}
+
+/*
+ * Interrupts are disabled on entering
+ */
+static void
+sport_uart_console_write(struct console *co, const char *s, unsigned int count)
+{
+ struct sport_uart_port *up = bfin_sport_uart_ports[co->index];
+ unsigned long flags;
+
+ spin_lock_irqsave(&up->port.lock, flags);
+
+ if (SPORT_GET_TCR1(up) & TSPEN)
+ uart_console_write(&up->port, s, count, sport_uart_console_putchar);
+ else {
+ /* dummy data to start sport */
+ while (SPORT_GET_STAT(up) & TXF)
+ barrier();
+ SPORT_PUT_TX(up, 0xffff);
+ /* Enable transmit, then an interrupt will generated */
+ SPORT_PUT_TCR1(up, (SPORT_GET_TCR1(up) | TSPEN));
+ SSYNC();
+
+ uart_console_write(&up->port, s, count, sport_uart_console_putchar);
+
+ /* Although the hold register is empty, last byte is still in shift
+ * register and not sent out yet. So, put a dummy data into TX FIFO.
+ * Then, sport tx stops when last byte is shift out and the dummy
+ * data is moved into the shift register.
+ */
+ while (SPORT_GET_STAT(up) & TXF)
+ barrier();
+ SPORT_PUT_TX(up, 0xffff);
+ while (!(SPORT_GET_STAT(up) & TXHRE))
+ barrier();
+
+ /* Stop sport tx transfer */
+ SPORT_PUT_TCR1(up, (SPORT_GET_TCR1(up) & ~TSPEN));
+ SSYNC();
+ }
+
+ spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+static struct uart_driver sport_uart_reg;
+
+static struct console sport_uart_console = {
+ .name = DEVICE_NAME,
+ .write = sport_uart_console_write,
+ .device = uart_console_device,
+ .setup = sport_uart_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &sport_uart_reg,
+};
+
+#define SPORT_UART_CONSOLE (&sport_uart_console)
+#else
+#define SPORT_UART_CONSOLE NULL
+#endif /* CONFIG_SERIAL_BFIN_SPORT_CONSOLE */
+
+
+static struct uart_driver sport_uart_reg = {
+ .owner = THIS_MODULE,
+ .driver_name = DRV_NAME,
+ .dev_name = DEVICE_NAME,
+ .major = 204,
+ .minor = 84,
+ .nr = BFIN_SPORT_UART_MAX_PORTS,
+ .cons = SPORT_UART_CONSOLE,
+};
+
+#ifdef CONFIG_PM
+static int sport_uart_suspend(struct device *dev)
+{
+ struct sport_uart_port *sport = dev_get_drvdata(dev);
+
+ dev_dbg(dev, "%s enter\n", __func__);
+ if (sport)
+ uart_suspend_port(&sport_uart_reg, &sport->port);
+
+ return 0;
+}
+
+static int sport_uart_resume(struct device *dev)
+{
+ struct sport_uart_port *sport = dev_get_drvdata(dev);
+
+ dev_dbg(dev, "%s enter\n", __func__);
+ if (sport)
+ uart_resume_port(&sport_uart_reg, &sport->port);
+
+ return 0;
+}
+
+static struct dev_pm_ops bfin_sport_uart_dev_pm_ops = {
+ .suspend = sport_uart_suspend,
+ .resume = sport_uart_resume,
+};
+#endif
+
+static int __devinit sport_uart_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct sport_uart_port *sport;
+ int ret = 0;
+
+ dev_dbg(&pdev->dev, "%s enter\n", __func__);
+
+ if (pdev->id < 0 || pdev->id >= BFIN_SPORT_UART_MAX_PORTS) {
+ dev_err(&pdev->dev, "Wrong sport uart platform device id.\n");
+ return -ENOENT;
+ }
+
+ if (bfin_sport_uart_ports[pdev->id] == NULL) {
+ bfin_sport_uart_ports[pdev->id] =
+ kzalloc(sizeof(struct sport_uart_port), GFP_KERNEL);
+ sport = bfin_sport_uart_ports[pdev->id];
+ if (!sport) {
+ dev_err(&pdev->dev,
+ "Fail to malloc sport_uart_port\n");
+ return -ENOMEM;
+ }
+
+ ret = peripheral_request_list(
+ (unsigned short *)pdev->dev.platform_data, DRV_NAME);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "Fail to request SPORT peripherals\n");
+ goto out_error_free_mem;
+ }
+
+ spin_lock_init(&sport->port.lock);
+ sport->port.fifosize = SPORT_TX_FIFO_SIZE,
+ sport->port.ops = &sport_uart_ops;
+ sport->port.line = pdev->id;
+ sport->port.iotype = UPIO_MEM;
+ sport->port.flags = UPF_BOOT_AUTOCONF;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (res == NULL) {
+ dev_err(&pdev->dev, "Cannot get IORESOURCE_MEM\n");
+ ret = -ENOENT;
+ goto out_error_free_peripherals;
+ }
+
+ sport->port.membase = ioremap(res->start, resource_size(res));
+ if (!sport->port.membase) {
+ dev_err(&pdev->dev, "Cannot map sport IO\n");
+ ret = -ENXIO;
+ goto out_error_free_peripherals;
+ }
+ sport->port.mapbase = res->start;
+
+ sport->port.irq = platform_get_irq(pdev, 0);
+ if (sport->port.irq < 0) {
+ dev_err(&pdev->dev, "No sport RX/TX IRQ specified\n");
+ ret = -ENOENT;
+ goto out_error_unmap;
+ }
+
+ sport->err_irq = platform_get_irq(pdev, 1);
+ if (sport->err_irq < 0) {
+ dev_err(&pdev->dev, "No sport status IRQ specified\n");
+ ret = -ENOENT;
+ goto out_error_unmap;
+ }
+#ifdef CONFIG_SERIAL_BFIN_SPORT_CTSRTS
+ res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+ if (res == NULL)
+ sport->cts_pin = -1;
+ else
+ sport->cts_pin = res->start;
+
+ res = platform_get_resource(pdev, IORESOURCE_IO, 1);
+ if (res == NULL)
+ sport->rts_pin = -1;
+ else
+ sport->rts_pin = res->start;
+
+ if (sport->rts_pin >= 0)
+ gpio_request(sport->rts_pin, DRV_NAME);
+#endif
+ }
+
+#ifdef CONFIG_SERIAL_BFIN_SPORT_CONSOLE
+ if (!is_early_platform_device(pdev)) {
+#endif
+ sport = bfin_sport_uart_ports[pdev->id];
+ sport->port.dev = &pdev->dev;
+ dev_set_drvdata(&pdev->dev, sport);
+ ret = uart_add_one_port(&sport_uart_reg, &sport->port);
+#ifdef CONFIG_SERIAL_BFIN_SPORT_CONSOLE
+ }
+#endif
+ if (!ret)
+ return 0;
+
+ if (sport) {
+out_error_unmap:
+ iounmap(sport->port.membase);
+out_error_free_peripherals:
+ peripheral_free_list(
+ (unsigned short *)pdev->dev.platform_data);
+out_error_free_mem:
+ kfree(sport);
+ bfin_sport_uart_ports[pdev->id] = NULL;
+ }
+
+ return ret;
+}
+
+static int __devexit sport_uart_remove(struct platform_device *pdev)
+{
+ struct sport_uart_port *sport = platform_get_drvdata(pdev);
+
+ dev_dbg(&pdev->dev, "%s enter\n", __func__);
+ dev_set_drvdata(&pdev->dev, NULL);
+
+ if (sport) {
+ uart_remove_one_port(&sport_uart_reg, &sport->port);
+#ifdef CONFIG_SERIAL_BFIN_CTSRTS
+ if (sport->rts_pin >= 0)
+ gpio_free(sport->rts_pin);
+#endif
+ iounmap(sport->port.membase);
+ peripheral_free_list(
+ (unsigned short *)pdev->dev.platform_data);
+ kfree(sport);
+ bfin_sport_uart_ports[pdev->id] = NULL;
+ }
+
+ return 0;
+}
+
+static struct platform_driver sport_uart_driver = {
+ .probe = sport_uart_probe,
+ .remove = __devexit_p(sport_uart_remove),
+ .driver = {
+ .name = DRV_NAME,
+#ifdef CONFIG_PM
+ .pm = &bfin_sport_uart_dev_pm_ops,
+#endif
+ },
+};
+
+#ifdef CONFIG_SERIAL_BFIN_SPORT_CONSOLE
+static __initdata struct early_platform_driver early_sport_uart_driver = {
+ .class_str = CLASS_BFIN_SPORT_CONSOLE,
+ .pdrv = &sport_uart_driver,
+ .requested_id = EARLY_PLATFORM_ID_UNSET,
+};
+
+static int __init sport_uart_rs_console_init(void)
+{
+ early_platform_driver_register(&early_sport_uart_driver, DRV_NAME);
+
+ early_platform_driver_probe(CLASS_BFIN_SPORT_CONSOLE,
+ BFIN_SPORT_UART_MAX_PORTS, 0);
+
+ register_console(&sport_uart_console);
+
+ return 0;
+}
+console_initcall(sport_uart_rs_console_init);
+#endif
+
+static int __init sport_uart_init(void)
+{
+ int ret;
+
+ pr_info("Blackfin uart over sport driver\n");
+
+ ret = uart_register_driver(&sport_uart_reg);
+ if (ret) {
+ pr_err("failed to register %s:%d\n",
+ sport_uart_reg.driver_name, ret);
+ return ret;
+ }
+
+ ret = platform_driver_register(&sport_uart_driver);
+ if (ret) {
+ pr_err("failed to register sport uart driver:%d\n", ret);
+ uart_unregister_driver(&sport_uart_reg);
+ }
+
+ return ret;
+}
+module_init(sport_uart_init);
+
+static void __exit sport_uart_exit(void)
+{
+ platform_driver_unregister(&sport_uart_driver);
+ uart_unregister_driver(&sport_uart_reg);
+}
+module_exit(sport_uart_exit);
+
+MODULE_AUTHOR("Sonic Zhang, Roy Huang");
+MODULE_DESCRIPTION("Blackfin serial over SPORT driver");
+MODULE_LICENSE("GPL");