Merge tag 'tty-5.12-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 set of tty/serial driver changes for 5.12-rc1.

  Nothing huge, just lots of good cleanups and additions:

   - n_tty line discipline cleanups

   - vt core cleanups and reworks to make the code more "modern"

   - stm32 driver additions

   - tty led support added to the tty core and led layer

   - minor serial driver fixups and additions

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (54 commits)
  serial: core: Remove BUG_ON(in_interrupt()) check
  vt_ioctl: Remove in_interrupt() check
  dt-bindings: serial: imx: Switch to my personal address
  vt: keyboard, use new API for keyboard_tasklet
  serial: stm32: improve platform_get_irq condition handling in init_port
  serial: ifx6x60: Remove driver for deprecated platform
  tty: fix up iterate_tty_read() EOVERFLOW handling
  tty: fix up hung_up_tty_read() conversion
  tty: fix up hung_up_tty_write() conversion
  tty: teach the n_tty ICANON case about the new "cookie continuations" too
  tty: teach n_tty line discipline about the new "cookie continuations"
  tty: clean up legacy leftovers from n_tty line discipline
  tty: implement read_iter
  tty: convert tty_ldisc_ops 'read()' function to take a kernel pointer
  serial: remove sirf prima/atlas driver
  serial: mxs-auart: Remove <asm/cacheflush.h>
  serial: mxs-auart: Remove serial_mxs_probe_dt()
  serial: fsl_lpuart: Use of_device_get_match_data()
  dt-bindings: serial: renesas,hscif: Add r8a779a0 support
  tty: serial: Drop unused efm32 serial driver
  ...

include/linux/tty.h

@@ -240,8 +240,7 @@ struct tty_port {
 	wait_queue_head_t	delta_msr_wait;	/* Modem status change */
 	unsigned long		flags;		/* User TTY flags ASYNC_ */
 	unsigned long		iflags;		/* Internal flags TTY_PORT_ */
-	unsigned char		console:1,	/* port is a console */
-				low_latency:1;	/* optional: tune for latency */
+	unsigned char		console:1;	/* port is a console */
 	struct mutex		mutex;		/* Locking */
 	struct mutex		buf_mutex;	/* Buffer alloc lock */
 	unsigned char		*xmit_buf;	/* Optional buffer */
@@ -416,12 +415,14 @@ extern struct tty_struct *get_current_tty(void);
 /* tty_io.c */
 extern int __init tty_init(void);
 extern const char *tty_name(const struct tty_struct *tty);
-extern struct tty_struct *tty_kopen(dev_t device);
+extern struct tty_struct *tty_kopen_exclusive(dev_t device);
+extern struct tty_struct *tty_kopen_shared(dev_t device);
 extern void tty_kclose(struct tty_struct *tty);
 extern int tty_dev_name_to_number(const char *name, dev_t *number);
 extern int tty_ldisc_lock(struct tty_struct *tty, unsigned long timeout);
 extern void tty_ldisc_unlock(struct tty_struct *tty);
 extern ssize_t redirected_tty_write(struct kiocb *, struct iov_iter *);
+extern struct file *tty_release_redirect(struct tty_struct *tty);
 #else
 static inline void tty_kref_put(struct tty_struct *tty)
 { }
@@ -442,7 +443,7 @@ static inline int __init tty_init(void)
 { return 0; }
 static inline const char *tty_name(const struct tty_struct *tty)
 { return "(none)"; }
-static inline struct tty_struct *tty_kopen(dev_t device)
+static inline struct tty_struct *tty_kopen_exclusive(dev_t device)
 { return ERR_PTR(-ENODEV); }
 static inline void tty_kclose(struct tty_struct *tty)
 { }
@@ -500,6 +501,8 @@ extern void tty_unthrottle(struct tty_struct *tty);
 extern int tty_throttle_safe(struct tty_struct *tty);
 extern int tty_unthrottle_safe(struct tty_struct *tty);
 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
+extern int tty_get_icount(struct tty_struct *tty,
+			  struct serial_icounter_struct *icount);
 extern int is_current_pgrp_orphaned(void);
 extern void tty_hangup(struct tty_struct *tty);
 extern void tty_vhangup(struct tty_struct *tty);