Merge tag 'tty-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here is the big tty and serial driver update for 4.4-rc1.

  Lots of serial driver updates and a few small tty core changes.  Full
  details in the shortlog.

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

* tag 'tty-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (148 commits)
  tty: Use unbound workqueue for all input workers
  tty: Abstract tty buffer work
  tty: Prevent tty teardown during tty_write_message()
  tty: core: Use correct spinlock flavor in tiocspgrp()
  tty: Combine SIGTTOU/SIGTTIN handling
  serial: amba-pl011: fix incorrect integer size in pl011_fifo_to_tty()
  ttyFDC: Fix build problems due to use of module_{init,exit}
  tty: remove unneeded return statement
  serial: 8250_mid: add support for DMA engine handling from UART MMIO
  dmaengine: hsu: remove platform data
  dmaengine: hsu: introduce stubs for the exported functions
  dmaengine: hsu: make the UART driver in control of selecting this driver
  serial: fix mctrl helper functions
  serial: 8250_pci: Intel MID UART support to its own driver
  serial: fsl_lpuart: add earlycon support
  tty: disable unbind for old 74xx based serial/mpsc console port
  serial: pl011: Spelling s/clocks-names/clock-names/
  n_tty: Remove reader wakeups for TTY_BREAK/TTY_PARITY chars
  tty: synclink, fix indentation
  serial: at91, fix rs485 properties
  ...

1 files changed, 16 insertions, 12 deletions

diff --git a/drivers/tty/n_r3964.c b/drivers/tty/n_r3964.c
index 8b157d68a03e..345111467b85 100644
--- a/drivers/tty/n_r3964.c
+++ b/drivers/tty/n_r3964.c
@@ -276,7 +276,7 @@ static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code)
 			add_msg(pHeader->owner, R3964_MSG_ACK, pHeader->length,
 				error_code, NULL);
 		}
-		wake_up_interruptible(&pInfo->read_wait);
+		wake_up_interruptible(&pInfo->tty->read_wait);
 	}
 
 	spin_lock_irqsave(&pInfo->lock, flags);
@@ -542,7 +542,7 @@ static void on_receive_block(struct r3964_info *pInfo)
 				pBlock);
 		}
 	}
-	wake_up_interruptible(&pInfo->read_wait);
+	wake_up_interruptible(&pInfo->tty->read_wait);
 
 	pInfo->state = R3964_IDLE;
 
@@ -978,8 +978,8 @@ static int r3964_open(struct tty_struct *tty)
 	}
 
 	spin_lock_init(&pInfo->lock);
+	mutex_init(&pInfo->read_lock);
 	pInfo->tty = tty;
-	init_waitqueue_head(&pInfo->read_wait);
 	pInfo->priority = R3964_MASTER;
 	pInfo->rx_first = pInfo->rx_last = NULL;
 	pInfo->tx_first = pInfo->tx_last = NULL;
@@ -1045,7 +1045,6 @@ static void r3964_close(struct tty_struct *tty)
 	}
 
 	/* Free buffers: */
-	wake_up_interruptible(&pInfo->read_wait);
 	kfree(pInfo->rx_buf);
 	TRACE_M("r3964_close - rx_buf kfree %p", pInfo->rx_buf);
 	kfree(pInfo->tx_buf);
@@ -1065,7 +1064,16 @@ static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
 
 	TRACE_L("read()");
 
-	tty_lock(tty);
+	/*
+	 *	Internal serialization of reads.
+	 */
+	if (file->f_flags & O_NONBLOCK) {
+		if (!mutex_trylock(&pInfo->read_lock))
+			return -EAGAIN;
+	} else {
+		if (mutex_lock_interruptible(&pInfo->read_lock))
+			return -ERESTARTSYS;
+	}
 
 	pClient = findClient(pInfo, task_pid(current));
 	if (pClient) {
@@ -1077,7 +1085,7 @@ static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
 				goto unlock;
 			}
 			/* block until there is a message: */
-			wait_event_interruptible_tty(tty, pInfo->read_wait,
+			wait_event_interruptible(tty->read_wait,
 					(pMsg = remove_msg(pInfo, pClient)));
 		}
 
@@ -1107,7 +1115,7 @@ static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
 	}
 	ret = -EPERM;
 unlock:
-	tty_unlock(tty);
+	mutex_unlock(&pInfo->read_lock);
 	return ret;
 }
 
@@ -1156,8 +1164,6 @@ static ssize_t r3964_write(struct tty_struct *tty, struct file *file,
 	pHeader->locks = 0;
 	pHeader->owner = NULL;
 
-	tty_lock(tty);
-
 	pClient = findClient(pInfo, task_pid(current));
 	if (pClient) {
 		pHeader->owner = pClient;
@@ -1175,8 +1181,6 @@ static ssize_t r3964_write(struct tty_struct *tty, struct file *file,
 	add_tx_queue(pInfo, pHeader);
 	trigger_transmit(pInfo);
 
-	tty_unlock(tty);
-
 	return 0;
 }
 
@@ -1227,7 +1231,7 @@ static unsigned int r3964_poll(struct tty_struct *tty, struct file *file,
 
 	pClient = findClient(pInfo, task_pid(current));
 	if (pClient) {
-		poll_wait(file, &pInfo->read_wait, wait);
+		poll_wait(file, &tty->read_wait, wait);
 		spin_lock_irqsave(&pInfo->lock, flags);
 		pMsg = pClient->first_msg;
 		spin_unlock_irqrestore(&pInfo->lock, flags);