Merge tag 'tty-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver patches from Greg KH:
 "Here's the big tty/serial driver pull request for 3.12-rc1.

  Lots of n_tty reworks to resolve some very long-standing issues,
  removing the 3-4 different locks that were taken for every character.
  This code has been beaten on for a long time in linux-next with no
  reported regressions.

  Other than that, a range of serial and tty driver updates and
  revisions.  Full details in the shortlog"

* tag 'tty-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (226 commits)
  hvc_xen: Remove unnecessary __GFP_ZERO from kzalloc
  serial: imx: initialize the local variable
  tty: ar933x_uart: add device tree support and binding documentation
  tty: ar933x_uart: allow to build the driver as a module
  ARM: dts: msm: Update uartdm compatible strings
  devicetree: serial: Document msm_serial bindings
  serial: unify serial bindings into a single dir
  serial: fsl-imx-uart: Cleanup duplicate device tree binding
  tty: ar933x_uart: use config_enabled() macro to clean up ifdefs
  tty: ar933x_uart: remove superfluous assignment of ar933x_uart_driver.nr
  tty: ar933x_uart: use the clk API to get the uart clock
  tty: serial: cpm_uart: Adding proper request of GPIO used by cpm_uart driver
  serial: sirf: fix the amount of serial ports
  serial: sirf: define macro for some magic numbers of USP
  serial: icom: move array overflow checks earlier
  TTY: amiserial, remove unnecessary platform_set_drvdata()
  serial: st-asc: remove unnecessary platform_set_drvdata()
  msm_serial: Send more than 1 character on the console w/ UARTDM
  msm_serial: Add support for non-GSBI UARTDM devices
  msm_serial: Switch clock consumer strings and simplify code
  ...

1 files changed, 11 insertions, 5 deletions

diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c
index ee7c8123c374..d0d972f7e43e 100644
--- a/drivers/tty/serial/serial-tegra.c
+++ b/drivers/tty/serial/serial-tegra.c
@@ -571,7 +571,9 @@ static void tegra_uart_rx_dma_complete(void *args)
 
 	tegra_uart_handle_rx_pio(tup, port);
 	if (tty) {
+		spin_unlock_irqrestore(&u->lock, flags);
 		tty_flip_buffer_push(port);
+		spin_lock_irqsave(&u->lock, flags);
 		tty_kref_put(tty);
 	}
 	tegra_uart_start_rx_dma(tup);
@@ -583,11 +585,13 @@ static void tegra_uart_rx_dma_complete(void *args)
 	spin_unlock_irqrestore(&u->lock, flags);
 }
 
-static void tegra_uart_handle_rx_dma(struct tegra_uart_port *tup)
+static void tegra_uart_handle_rx_dma(struct tegra_uart_port *tup,
+		unsigned long *flags)
 {
 	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;
+	struct uart_port *u = &tup->uport;
 	int count;
 
 	/* Deactivate flow control to stop sender */
@@ -604,7 +608,9 @@ static void tegra_uart_handle_rx_dma(struct tegra_uart_port *tup)
 
 	tegra_uart_handle_rx_pio(tup, port);
 	if (tty) {
+		spin_unlock_irqrestore(&u->lock, *flags);
 		tty_flip_buffer_push(port);
+		spin_lock_irqsave(&u->lock, *flags);
 		tty_kref_put(tty);
 	}
 	tegra_uart_start_rx_dma(tup);
@@ -671,7 +677,7 @@ static irqreturn_t tegra_uart_isr(int irq, void *data)
 		iir = tegra_uart_read(tup, UART_IIR);
 		if (iir & UART_IIR_NO_INT) {
 			if (is_rx_int) {
-				tegra_uart_handle_rx_dma(tup);
+				tegra_uart_handle_rx_dma(tup, &flags);
 				if (tup->rx_in_progress) {
 					ier = tup->ier_shadow;
 					ier |= (UART_IER_RLSI | UART_IER_RTOIE |
@@ -1206,7 +1212,7 @@ static struct uart_driver tegra_uart_driver = {
 	.owner		= THIS_MODULE,
 	.driver_name	= "tegra_hsuart",
 	.dev_name	= "ttyTHS",
-	.cons		= 0,
+	.cons		= NULL,
 	.nr		= TEGRA_UART_MAXIMUM,
 };
 
@@ -1237,13 +1243,13 @@ static int tegra_uart_parse_dt(struct platform_device *pdev,
 	return 0;
 }
 
-struct tegra_uart_chip_data tegra20_uart_chip_data = {
+static 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 = {
+static 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,