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, 14 insertions, 2 deletions

diff --git a/include/linux/tty_ldisc.h b/include/linux/tty_ldisc.h
index a1b048999821..f15c898ff462 100644
--- a/include/linux/tty_ldisc.h
+++ b/include/linux/tty_ldisc.h
@@ -109,6 +109,17 @@
  *
  *	Tells the discipline that the DCD pin has changed its status.
  *	Used exclusively by the N_PPS (Pulse-Per-Second) line discipline.
+ *
+ * int	(*receive_buf2)(struct tty_struct *, const unsigned char *cp,
+ *			char *fp, int count);
+ *
+ *	This function is called by the low-level tty driver to send
+ *	characters received by the hardware to the line discpline for
+ *	processing.  <cp> is a pointer to the buffer of input
+ *	character received by the device.  <fp> is a pointer to a
+ *	pointer of flag bytes which indicate whether a character was
+ *	received with a parity error, etc.
+ *	If assigned, prefer this function for automatic flow control.
  */
 
 #include <linux/fs.h>
@@ -195,6 +206,8 @@ struct tty_ldisc_ops {
 	void	(*write_wakeup)(struct tty_struct *);
 	void	(*dcd_change)(struct tty_struct *, unsigned int);
 	void	(*fasync)(struct tty_struct *tty, int on);
+	int	(*receive_buf2)(struct tty_struct *, const unsigned char *cp,
+				char *fp, int count);
 
 	struct  module *owner;
 
@@ -203,8 +216,7 @@ struct tty_ldisc_ops {
 
 struct tty_ldisc {
 	struct tty_ldisc_ops *ops;
-	atomic_t users;
-	wait_queue_head_t wq_idle;
+	struct tty_struct *tty;
 };
 
 #define TTY_LDISC_MAGIC	0x5403