From b468e688240b58ece498c430c377bb81b78a41f1 Mon Sep 17 00:00:00 2001
From: Jiri Slaby <jslaby@suse.cz>
Date: Tue, 14 Sep 2021 11:11:20 +0200
Subject: tty: remove flags from struct tty_ldisc_ops

The last user was apparently removed by commit a352def21a64 (tty: Ldisc
revamp) in 2008. So remove the field completely, the only setter
(n_tty_inherit_ops) and also its only possible value
(LDISC_FLAG_DEFINED).

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210914091134.17426-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 include/linux/tty_ldisc.h | 3 ---
 1 file changed, 3 deletions(-)

(limited to 'include/linux')

diff --git a/include/linux/tty_ldisc.h b/include/linux/tty_ldisc.h
index b1d812e902aa..1f37184eee63 100644
--- a/include/linux/tty_ldisc.h
+++ b/include/linux/tty_ldisc.h
@@ -180,7 +180,6 @@ extern int ldsem_down_write_nested(struct ld_semaphore *sem, int subclass,
 struct tty_ldisc_ops {
 	char	*name;
 	int	num;
-	int	flags;
 
 	/*
 	 * The following routines are called from above.
@@ -220,8 +219,6 @@ struct tty_ldisc {
 	struct tty_struct *tty;
 };
 
-#define LDISC_FLAG_DEFINED	0x00000001
-
 #define MODULE_ALIAS_LDISC(ldisc) \
 	MODULE_ALIAS("tty-ldisc-" __stringify(ldisc))
 
-- 
cgit v1.2.3


From 7894193436b65f304ba790abe2532a7a3bbeb7c8 Mon Sep 17 00:00:00 2001
From: Jiri Slaby <jslaby@suse.cz>
Date: Tue, 14 Sep 2021 11:11:21 +0200
Subject: tty: remove extern from functions in tty headers

After the recent headers cleanup, some function declarations still have
extern before them. It is superfluous (for function declarations), so
remove extern from those which still have it.

This unifies them with the rest of the files.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210914091134.17426-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 include/linux/tty.h        | 139 ++++++++++++++++++++++-----------------------
 include/linux/tty_driver.h |   8 +--
 include/linux/tty_flip.h   |  20 +++----
 include/linux/tty_ldisc.h  |  22 +++----
 4 files changed, 94 insertions(+), 95 deletions(-)

(limited to 'include/linux')

diff --git a/include/linux/tty.h b/include/linux/tty.h
index 168e57e40bbb..15453b0c4081 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -252,20 +252,20 @@ static inline bool tty_throttled(struct tty_struct *tty)
 }
 
 #ifdef CONFIG_TTY
-extern void tty_kref_put(struct tty_struct *tty);
-extern struct pid *tty_get_pgrp(struct tty_struct *tty);
-extern void tty_vhangup_self(void);
-extern void disassociate_ctty(int priv);
-extern dev_t tty_devnum(struct tty_struct *tty);
-extern void proc_clear_tty(struct task_struct *p);
-extern struct tty_struct *get_current_tty(void);
+void tty_kref_put(struct tty_struct *tty);
+struct pid *tty_get_pgrp(struct tty_struct *tty);
+void tty_vhangup_self(void);
+void disassociate_ctty(int priv);
+dev_t tty_devnum(struct tty_struct *tty);
+void proc_clear_tty(struct task_struct *p);
+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_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);
+int __init tty_init(void);
+const char *tty_name(const struct tty_struct *tty);
+struct tty_struct *tty_kopen_exclusive(dev_t device);
+struct tty_struct *tty_kopen_shared(dev_t device);
+void tty_kclose(struct tty_struct *tty);
+int tty_dev_name_to_number(const char *name, dev_t *number);
 #else
 static inline void tty_kref_put(struct tty_struct *tty)
 { }
@@ -296,7 +296,7 @@ static inline int tty_dev_name_to_number(const char *name, dev_t *number)
 
 extern struct ktermios tty_std_termios;
 
-extern int vcs_init(void);
+int vcs_init(void);
 
 extern struct class *tty_class;
 
@@ -316,34 +316,34 @@ static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
 	return tty;
 }
 
-extern const char *tty_driver_name(const struct tty_struct *tty);
-extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
-extern void stop_tty(struct tty_struct *tty);
-extern void start_tty(struct tty_struct *tty);
-extern void tty_write_message(struct tty_struct *tty, char *msg);
-extern int tty_send_xchar(struct tty_struct *tty, char ch);
-extern int tty_put_char(struct tty_struct *tty, unsigned char c);
-extern unsigned int tty_chars_in_buffer(struct tty_struct *tty);
-extern unsigned int tty_write_room(struct tty_struct *tty);
-extern void tty_driver_flush_buffer(struct tty_struct *tty);
-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);
-extern int tty_hung_up_p(struct file *filp);
-extern void do_SAK(struct tty_struct *tty);
-extern void __do_SAK(struct tty_struct *tty);
-extern void no_tty(void);
-extern speed_t tty_termios_baud_rate(struct ktermios *termios);
-extern void tty_termios_encode_baud_rate(struct ktermios *termios,
-						speed_t ibaud, speed_t obaud);
-extern void tty_encode_baud_rate(struct tty_struct *tty,
-						speed_t ibaud, speed_t obaud);
+const char *tty_driver_name(const struct tty_struct *tty);
+void tty_wait_until_sent(struct tty_struct *tty, long timeout);
+void stop_tty(struct tty_struct *tty);
+void start_tty(struct tty_struct *tty);
+void tty_write_message(struct tty_struct *tty, char *msg);
+int tty_send_xchar(struct tty_struct *tty, char ch);
+int tty_put_char(struct tty_struct *tty, unsigned char c);
+unsigned int tty_chars_in_buffer(struct tty_struct *tty);
+unsigned int tty_write_room(struct tty_struct *tty);
+void tty_driver_flush_buffer(struct tty_struct *tty);
+void tty_unthrottle(struct tty_struct *tty);
+int tty_throttle_safe(struct tty_struct *tty);
+int tty_unthrottle_safe(struct tty_struct *tty);
+int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
+int tty_get_icount(struct tty_struct *tty,
+		struct serial_icounter_struct *icount);
+int is_current_pgrp_orphaned(void);
+void tty_hangup(struct tty_struct *tty);
+void tty_vhangup(struct tty_struct *tty);
+int tty_hung_up_p(struct file *filp);
+void do_SAK(struct tty_struct *tty);
+void __do_SAK(struct tty_struct *tty);
+void no_tty(void);
+speed_t tty_termios_baud_rate(struct ktermios *termios);
+void tty_termios_encode_baud_rate(struct ktermios *termios, speed_t ibaud,
+		speed_t obaud);
+void tty_encode_baud_rate(struct tty_struct *tty, speed_t ibaud,
+		speed_t obaud);
 
 /**
  *	tty_get_baud_rate	-	get tty bit rates
@@ -363,37 +363,37 @@ static inline speed_t tty_get_baud_rate(struct tty_struct *tty)
 unsigned char tty_get_char_size(unsigned int cflag);
 unsigned char tty_get_frame_size(unsigned int cflag);
 
-extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
-extern int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b);
-extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
+void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
+int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b);
+int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
 
-extern void tty_wakeup(struct tty_struct *tty);
+void tty_wakeup(struct tty_struct *tty);
 
-extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
+int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
 			unsigned int cmd, unsigned long arg);
-extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
-extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
-extern void tty_release_struct(struct tty_struct *tty, int idx);
-extern void tty_init_termios(struct tty_struct *tty);
-extern void tty_save_termios(struct tty_struct *tty);
-extern int tty_standard_install(struct tty_driver *driver,
+int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
+struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
+void tty_release_struct(struct tty_struct *tty, int idx);
+void tty_init_termios(struct tty_struct *tty);
+void tty_save_termios(struct tty_struct *tty);
+int tty_standard_install(struct tty_driver *driver,
 		struct tty_struct *tty);
 
 extern struct mutex tty_mutex;
 
 /* n_tty.c */
-extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
+void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
 #ifdef CONFIG_TTY
-extern void __init n_tty_init(void);
+void __init n_tty_init(void);
 #else
 static inline void n_tty_init(void) { }
 #endif
 
 /* tty_audit.c */
 #ifdef CONFIG_AUDIT
-extern void tty_audit_exit(void);
-extern void tty_audit_fork(struct signal_struct *sig);
-extern int tty_audit_push(void);
+void tty_audit_exit(void);
+void tty_audit_fork(struct signal_struct *sig);
+int tty_audit_push(void);
 #else
 static inline void tty_audit_exit(void)
 {
@@ -408,24 +408,23 @@ static inline int tty_audit_push(void)
 #endif
 
 /* tty_ioctl.c */
-extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
-		       unsigned int cmd, unsigned long arg);
+int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
+		unsigned int cmd, unsigned long arg);
 
 /* vt.c */
 
-extern int vt_ioctl(struct tty_struct *tty,
-		    unsigned int cmd, unsigned long arg);
+int vt_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg);
 
-extern long vt_compat_ioctl(struct tty_struct *tty,
-		     unsigned int cmd, unsigned long arg);
+long vt_compat_ioctl(struct tty_struct *tty, unsigned int cmd,
+		unsigned long arg);
 
 /* tty_mutex.c */
 /* functions for preparation of BKL removal */
-extern void tty_lock(struct tty_struct *tty);
-extern int  tty_lock_interruptible(struct tty_struct *tty);
-extern void tty_unlock(struct tty_struct *tty);
-extern void tty_lock_slave(struct tty_struct *tty);
-extern void tty_unlock_slave(struct tty_struct *tty);
-extern void tty_set_lock_subclass(struct tty_struct *tty);
+void tty_lock(struct tty_struct *tty);
+int  tty_lock_interruptible(struct tty_struct *tty);
+void tty_unlock(struct tty_struct *tty);
+void tty_lock_slave(struct tty_struct *tty);
+void tty_unlock_slave(struct tty_struct *tty);
+void tty_set_lock_subclass(struct tty_struct *tty);
 
 #endif
diff --git a/include/linux/tty_driver.h b/include/linux/tty_driver.h
index c20431d8def8..29e1cf178afb 100644
--- a/include/linux/tty_driver.h
+++ b/include/linux/tty_driver.h
@@ -327,11 +327,11 @@ struct tty_driver {
 
 extern struct list_head tty_drivers;
 
-extern struct tty_driver *__tty_alloc_driver(unsigned int lines,
-		struct module *owner, unsigned long flags);
-extern struct tty_driver *tty_find_polling_driver(char *name, int *line);
+struct tty_driver *__tty_alloc_driver(unsigned int lines, struct module *owner,
+		unsigned long flags);
+struct tty_driver *tty_find_polling_driver(char *name, int *line);
 
-extern void tty_driver_kref_put(struct tty_driver *driver);
+void tty_driver_kref_put(struct tty_driver *driver);
 
 /* Use TTY_DRIVER_* flags below */
 #define tty_alloc_driver(lines, flags) \
diff --git a/include/linux/tty_flip.h b/include/linux/tty_flip.h
index 32284992b31a..9916acb5de49 100644
--- a/include/linux/tty_flip.h
+++ b/include/linux/tty_flip.h
@@ -7,16 +7,16 @@
 
 struct tty_ldisc;
 
-extern int tty_buffer_set_limit(struct tty_port *port, int limit);
-extern unsigned int tty_buffer_space_avail(struct tty_port *port);
-extern int tty_buffer_request_room(struct tty_port *port, size_t size);
-extern int tty_insert_flip_string_flags(struct tty_port *port,
+int tty_buffer_set_limit(struct tty_port *port, int limit);
+unsigned int tty_buffer_space_avail(struct tty_port *port);
+int tty_buffer_request_room(struct tty_port *port, size_t size);
+int tty_insert_flip_string_flags(struct tty_port *port,
 		const unsigned char *chars, const char *flags, size_t size);
-extern int tty_insert_flip_string_fixed_flag(struct tty_port *port,
+int tty_insert_flip_string_fixed_flag(struct tty_port *port,
 		const unsigned char *chars, char flag, size_t size);
-extern int tty_prepare_flip_string(struct tty_port *port,
-		unsigned char **chars, size_t size);
-extern void tty_flip_buffer_push(struct tty_port *port);
+int tty_prepare_flip_string(struct tty_port *port, unsigned char **chars,
+		size_t size);
+void tty_flip_buffer_push(struct tty_port *port);
 void tty_schedule_flip(struct tty_port *port);
 int __tty_insert_flip_char(struct tty_port *port, unsigned char ch, char flag);
 
@@ -45,7 +45,7 @@ static inline int tty_insert_flip_string(struct tty_port *port,
 int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p,
 		const char *f, int count);
 
-extern void tty_buffer_lock_exclusive(struct tty_port *port);
-extern void tty_buffer_unlock_exclusive(struct tty_port *port);
+void tty_buffer_lock_exclusive(struct tty_port *port);
+void tty_buffer_unlock_exclusive(struct tty_port *port);
 
 #endif /* _LINUX_TTY_FLIP_H */
diff --git a/include/linux/tty_ldisc.h b/include/linux/tty_ldisc.h
index 1f37184eee63..4d1c128afbfa 100644
--- a/include/linux/tty_ldisc.h
+++ b/include/linux/tty_ldisc.h
@@ -146,7 +146,7 @@ struct ld_semaphore {
 #endif
 };
 
-extern void __init_ldsem(struct ld_semaphore *sem, const char *name,
+void __init_ldsem(struct ld_semaphore *sem, const char *name,
 			 struct lock_class_key *key);
 
 #define init_ldsem(sem)						\
@@ -157,18 +157,18 @@ do {								\
 } while (0)
 
 
-extern int ldsem_down_read(struct ld_semaphore *sem, long timeout);
-extern int ldsem_down_read_trylock(struct ld_semaphore *sem);
-extern int ldsem_down_write(struct ld_semaphore *sem, long timeout);
-extern int ldsem_down_write_trylock(struct ld_semaphore *sem);
-extern void ldsem_up_read(struct ld_semaphore *sem);
-extern void ldsem_up_write(struct ld_semaphore *sem);
+int ldsem_down_read(struct ld_semaphore *sem, long timeout);
+int ldsem_down_read_trylock(struct ld_semaphore *sem);
+int ldsem_down_write(struct ld_semaphore *sem, long timeout);
+int ldsem_down_write_trylock(struct ld_semaphore *sem);
+void ldsem_up_read(struct ld_semaphore *sem);
+void ldsem_up_write(struct ld_semaphore *sem);
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
-extern int ldsem_down_read_nested(struct ld_semaphore *sem, int subclass,
-				  long timeout);
-extern int ldsem_down_write_nested(struct ld_semaphore *sem, int subclass,
-				   long timeout);
+int ldsem_down_read_nested(struct ld_semaphore *sem, int subclass,
+		long timeout);
+int ldsem_down_write_nested(struct ld_semaphore *sem, int subclass,
+		long timeout);
 #else
 # define ldsem_down_read_nested(sem, subclass, timeout)		\
 		ldsem_down_read(sem, timeout)
-- 
cgit v1.2.3


From 28f194da4a2c4d431552025a4386edaffab181bd Mon Sep 17 00:00:00 2001
From: Jiri Slaby <jslaby@suse.cz>
Date: Tue, 14 Sep 2021 11:11:22 +0200
Subject: tty: make tty_ldisc_ops::hangup return void

The documentation says that the return value of tty_ldisc_ops::hangup
hook is ignored. And it really is, so there is no point for its return
type to be int. Switch it to void and all the hooks too.

Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210914091134.17426-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 Documentation/driver-api/serial/tty.rst | 2 +-
 drivers/input/serio/serport.c           | 3 +--
 drivers/net/can/slcan.c                 | 3 +--
 drivers/net/ppp/ppp_async.c             | 3 +--
 drivers/net/ppp/ppp_synctty.c           | 3 +--
 drivers/net/slip/slip.c                 | 3 +--
 include/linux/tty_ldisc.h               | 2 +-
 sound/soc/codecs/cx20442.c              | 3 +--
 sound/soc/ti/ams-delta.c                | 3 +--
 9 files changed, 9 insertions(+), 16 deletions(-)

(limited to 'include/linux')

diff --git a/Documentation/driver-api/serial/tty.rst b/Documentation/driver-api/serial/tty.rst
index dd972caacf3e..4b709f392713 100644
--- a/Documentation/driver-api/serial/tty.rst
+++ b/Documentation/driver-api/serial/tty.rst
@@ -58,7 +58,7 @@ close()			This is called on a terminal when the line
 hangup()		Called when the tty line is hung up.
 			The line discipline should cease I/O to the tty.
 			No further calls into the ldisc code will occur.
-			The return value is ignored. Can sleep.
+			Can sleep.
 
 read()			(optional) A process requests reading data from
 			the line. Multiple read calls may occur in parallel
diff --git a/drivers/input/serio/serport.c b/drivers/input/serio/serport.c
index 7fbbe00e3553..17eb8f2aa48d 100644
--- a/drivers/input/serio/serport.c
+++ b/drivers/input/serio/serport.c
@@ -244,7 +244,7 @@ static int serport_ldisc_compat_ioctl(struct tty_struct *tty,
 }
 #endif
 
-static int serport_ldisc_hangup(struct tty_struct *tty)
+static void serport_ldisc_hangup(struct tty_struct *tty)
 {
 	struct serport *serport = (struct serport *) tty->disc_data;
 	unsigned long flags;
@@ -254,7 +254,6 @@ static int serport_ldisc_hangup(struct tty_struct *tty)
 	spin_unlock_irqrestore(&serport->lock, flags);
 
 	wake_up_interruptible(&serport->wait);
-	return 0;
 }
 
 static void serport_ldisc_write_wakeup(struct tty_struct * tty)
diff --git a/drivers/net/can/slcan.c b/drivers/net/can/slcan.c
index d42ec7d1bc14..012da4b8abe0 100644
--- a/drivers/net/can/slcan.c
+++ b/drivers/net/can/slcan.c
@@ -664,10 +664,9 @@ static void slcan_close(struct tty_struct *tty)
 	/* This will complete via sl_free_netdev */
 }
 
-static int slcan_hangup(struct tty_struct *tty)
+static void slcan_hangup(struct tty_struct *tty)
 {
 	slcan_close(tty);
-	return 0;
 }
 
 /* Perform I/O control on an active SLCAN channel. */
diff --git a/drivers/net/ppp/ppp_async.c b/drivers/net/ppp/ppp_async.c
index 29a93d6bfe37..78ec1bcebc4f 100644
--- a/drivers/net/ppp/ppp_async.c
+++ b/drivers/net/ppp/ppp_async.c
@@ -247,10 +247,9 @@ ppp_asynctty_close(struct tty_struct *tty)
  * Wait for I/O to driver to complete and unregister PPP channel.
  * This is already done by the close routine, so just call that.
  */
-static int ppp_asynctty_hangup(struct tty_struct *tty)
+static void ppp_asynctty_hangup(struct tty_struct *tty)
 {
 	ppp_asynctty_close(tty);
-	return 0;
 }
 
 /*
diff --git a/drivers/net/ppp/ppp_synctty.c b/drivers/net/ppp/ppp_synctty.c
index af3e048695b6..c249db7c466a 100644
--- a/drivers/net/ppp/ppp_synctty.c
+++ b/drivers/net/ppp/ppp_synctty.c
@@ -245,10 +245,9 @@ ppp_sync_close(struct tty_struct *tty)
  * Wait for I/O to driver to complete and unregister PPP channel.
  * This is already done by the close routine, so just call that.
  */
-static int ppp_sync_hangup(struct tty_struct *tty)
+static void ppp_sync_hangup(struct tty_struct *tty)
 {
 	ppp_sync_close(tty);
-	return 0;
 }
 
 /*
diff --git a/drivers/net/slip/slip.c b/drivers/net/slip/slip.c
index 5435b5689ce6..8be9d0c351b5 100644
--- a/drivers/net/slip/slip.c
+++ b/drivers/net/slip/slip.c
@@ -907,10 +907,9 @@ static void slip_close(struct tty_struct *tty)
 	/* This will complete via sl_free_netdev */
 }
 
-static int slip_hangup(struct tty_struct *tty)
+static void slip_hangup(struct tty_struct *tty)
 {
 	slip_close(tty);
-	return 0;
 }
  /************************************************************************
   *			STANDARD SLIP ENCAPSULATION		  	 *
diff --git a/include/linux/tty_ldisc.h b/include/linux/tty_ldisc.h
index 4d1c128afbfa..b85d84fb5f49 100644
--- a/include/linux/tty_ldisc.h
+++ b/include/linux/tty_ldisc.h
@@ -199,7 +199,7 @@ struct tty_ldisc_ops {
 	void	(*set_termios)(struct tty_struct *tty, struct ktermios *old);
 	__poll_t (*poll)(struct tty_struct *, struct file *,
 			     struct poll_table_struct *);
-	int	(*hangup)(struct tty_struct *tty);
+	void	(*hangup)(struct tty_struct *tty);
 
 	/*
 	 * The following routines are called from below.
diff --git a/sound/soc/codecs/cx20442.c b/sound/soc/codecs/cx20442.c
index 13258f3ca9aa..1af0bf5f1e2f 100644
--- a/sound/soc/codecs/cx20442.c
+++ b/sound/soc/codecs/cx20442.c
@@ -252,10 +252,9 @@ static void v253_close(struct tty_struct *tty)
 }
 
 /* Line discipline .hangup() */
-static int v253_hangup(struct tty_struct *tty)
+static void v253_hangup(struct tty_struct *tty)
 {
 	v253_close(tty);
-	return 0;
 }
 
 /* Line discipline .receive_buf() */
diff --git a/sound/soc/ti/ams-delta.c b/sound/soc/ti/ams-delta.c
index ecd24d412a9b..b1a32545babd 100644
--- a/sound/soc/ti/ams-delta.c
+++ b/sound/soc/ti/ams-delta.c
@@ -330,10 +330,9 @@ static void cx81801_close(struct tty_struct *tty)
 }
 
 /* Line discipline .hangup() */
-static int cx81801_hangup(struct tty_struct *tty)
+static void cx81801_hangup(struct tty_struct *tty)
 {
 	cx81801_close(tty);
-	return 0;
 }
 
 /* Line discipline .receive_buf() */
-- 
cgit v1.2.3


From dcc223e8b9bf3f987bcd3c327a6737022b39e35b Mon Sep 17 00:00:00 2001
From: Jiri Slaby <jslaby@suse.cz>
Date: Tue, 14 Sep 2021 11:11:23 +0200
Subject: tty: remove file from tty_mode_ioctl

The only user of 'file' parameter in tty_mode_ioctl is a BUG_ON check.
Provided it never crashed for anyone, it's an overkill to pass the
parameter to tty_mode_ioctl only for this check.

If we wanted to check 'file' there, we should handle it in more graceful
way anyway. Not by a BUG == crash.

Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Andreas Koensgen <ajk@comnets.uni-bremen.de>
Cc: Paul Mackerras <paulus@samba.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210914091134.17426-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/can/slcan.c       | 2 +-
 drivers/net/hamradio/6pack.c  | 2 +-
 drivers/net/ppp/ppp_async.c   | 2 +-
 drivers/net/ppp/ppp_synctty.c | 2 +-
 drivers/net/slip/slip.c       | 2 +-
 drivers/tty/tty_ioctl.c       | 8 ++------
 include/linux/tty.h           | 3 +--
 7 files changed, 8 insertions(+), 13 deletions(-)

(limited to 'include/linux')

diff --git a/drivers/net/can/slcan.c b/drivers/net/can/slcan.c
index 012da4b8abe0..9a4ebda30510 100644
--- a/drivers/net/can/slcan.c
+++ b/drivers/net/can/slcan.c
@@ -691,7 +691,7 @@ static int slcan_ioctl(struct tty_struct *tty, struct file *file,
 		return -EINVAL;
 
 	default:
-		return tty_mode_ioctl(tty, file, cmd, arg);
+		return tty_mode_ioctl(tty, cmd, arg);
 	}
 }
 
diff --git a/drivers/net/hamradio/6pack.c b/drivers/net/hamradio/6pack.c
index 8fe8887d506a..05404f7a3204 100644
--- a/drivers/net/hamradio/6pack.c
+++ b/drivers/net/hamradio/6pack.c
@@ -732,7 +732,7 @@ static int sixpack_ioctl(struct tty_struct *tty, struct file *file,
 			break;
 		}
 	default:
-		err = tty_mode_ioctl(tty, file, cmd, arg);
+		err = tty_mode_ioctl(tty, cmd, arg);
 	}
 
 	sp_put(sp);
diff --git a/drivers/net/ppp/ppp_async.c b/drivers/net/ppp/ppp_async.c
index 78ec1bcebc4f..6492523fc234 100644
--- a/drivers/net/ppp/ppp_async.c
+++ b/drivers/net/ppp/ppp_async.c
@@ -322,7 +322,7 @@ ppp_asynctty_ioctl(struct tty_struct *tty, struct file *file,
 
 	default:
 		/* Try the various mode ioctls */
-		err = tty_mode_ioctl(tty, file, cmd, arg);
+		err = tty_mode_ioctl(tty, cmd, arg);
 	}
 
 	ap_put(ap);
diff --git a/drivers/net/ppp/ppp_synctty.c b/drivers/net/ppp/ppp_synctty.c
index c249db7c466a..ebbfea0e1140 100644
--- a/drivers/net/ppp/ppp_synctty.c
+++ b/drivers/net/ppp/ppp_synctty.c
@@ -314,7 +314,7 @@ ppp_synctty_ioctl(struct tty_struct *tty, struct file *file,
 		break;
 
 	default:
-		err = tty_mode_ioctl(tty, file, cmd, arg);
+		err = tty_mode_ioctl(tty, cmd, arg);
 		break;
 	}
 
diff --git a/drivers/net/slip/slip.c b/drivers/net/slip/slip.c
index 8be9d0c351b5..9f3b4c1aa5ce 100644
--- a/drivers/net/slip/slip.c
+++ b/drivers/net/slip/slip.c
@@ -1173,7 +1173,7 @@ static int slip_ioctl(struct tty_struct *tty, struct file *file,
 	/* VSV changes end */
 #endif
 	default:
-		return tty_mode_ioctl(tty, file, cmd, arg);
+		return tty_mode_ioctl(tty, cmd, arg);
 	}
 }
 
diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c
index 507a25d692bb..99a29d72d294 100644
--- a/drivers/tty/tty_ioctl.c
+++ b/drivers/tty/tty_ioctl.c
@@ -675,7 +675,6 @@ static int tty_change_softcar(struct tty_struct *tty, int arg)
 /**
  *	tty_mode_ioctl		-	mode related ioctls
  *	@tty: tty for the ioctl
- *	@file: file pointer for the tty
  *	@cmd: command
  *	@arg: ioctl argument
  *
@@ -684,16 +683,13 @@ static int tty_change_softcar(struct tty_struct *tty, int arg)
  *	consistent mode setting.
  */
 
-int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
-			unsigned int cmd, unsigned long arg)
+int tty_mode_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg)
 {
 	struct tty_struct *real_tty;
 	void __user *p = (void __user *)arg;
 	int ret = 0;
 	struct ktermios kterm;
 
-	BUG_ON(file == NULL);
-
 	if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
 	    tty->driver->subtype == PTY_TYPE_MASTER)
 		real_tty = tty->link;
@@ -904,7 +900,7 @@ int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
 		return __tty_perform_flush(tty, arg);
 	default:
 		/* Try the mode commands */
-		return tty_mode_ioctl(tty, file, cmd, arg);
+		return tty_mode_ioctl(tty, cmd, arg);
 	}
 }
 EXPORT_SYMBOL(n_tty_ioctl_helper);
diff --git a/include/linux/tty.h b/include/linux/tty.h
index 15453b0c4081..5e73f577c2b4 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -369,8 +369,7 @@ int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
 
 void tty_wakeup(struct tty_struct *tty);
 
-int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
-			unsigned int cmd, unsigned long arg);
+int tty_mode_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg);
 int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
 struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
 void tty_release_struct(struct tty_struct *tty, int idx);
-- 
cgit v1.2.3


From 7c783601a3bc22a54cce0fb650259a983c8cafba Mon Sep 17 00:00:00 2001
From: Jiri Slaby <jslaby@suse.cz>
Date: Tue, 14 Sep 2021 11:11:24 +0200
Subject: tty: remove file from n_tty_ioctl_helper

After the previous patch, there are no users of 'file' in
n_tty_ioctl_helper. So remove it also from there.

Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210914091134.17426-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/bluetooth/hci_ldisc.c | 2 +-
 drivers/net/ppp/ppp_async.c   | 2 +-
 drivers/net/ppp/ppp_synctty.c | 2 +-
 drivers/tty/n_gsm.c           | 2 +-
 drivers/tty/n_hdlc.c          | 2 +-
 drivers/tty/n_tty.c           | 2 +-
 drivers/tty/tty_ioctl.c       | 4 ++--
 include/linux/tty.h           | 4 ++--
 net/nfc/nci/uart.c            | 2 +-
 9 files changed, 11 insertions(+), 11 deletions(-)

(limited to 'include/linux')

diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
index 5ed2cfa7da1d..824d1c7e3e53 100644
--- a/drivers/bluetooth/hci_ldisc.c
+++ b/drivers/bluetooth/hci_ldisc.c
@@ -790,7 +790,7 @@ static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file *file,
 		break;
 
 	default:
-		err = n_tty_ioctl_helper(tty, file, cmd, arg);
+		err = n_tty_ioctl_helper(tty, cmd, arg);
 		break;
 	}
 
diff --git a/drivers/net/ppp/ppp_async.c b/drivers/net/ppp/ppp_async.c
index 6492523fc234..f4429b93a9c8 100644
--- a/drivers/net/ppp/ppp_async.c
+++ b/drivers/net/ppp/ppp_async.c
@@ -310,7 +310,7 @@ ppp_asynctty_ioctl(struct tty_struct *tty, struct file *file,
 		/* flush our buffers and the serial port's buffer */
 		if (arg == TCIOFLUSH || arg == TCOFLUSH)
 			ppp_async_flush_output(ap);
-		err = n_tty_ioctl_helper(tty, file, cmd, arg);
+		err = n_tty_ioctl_helper(tty, cmd, arg);
 		break;
 
 	case FIONREAD:
diff --git a/drivers/net/ppp/ppp_synctty.c b/drivers/net/ppp/ppp_synctty.c
index ebbfea0e1140..b3a71b409a80 100644
--- a/drivers/net/ppp/ppp_synctty.c
+++ b/drivers/net/ppp/ppp_synctty.c
@@ -303,7 +303,7 @@ ppp_synctty_ioctl(struct tty_struct *tty, struct file *file,
 		/* flush our buffers and the serial port's buffer */
 		if (arg == TCIOFLUSH || arg == TCOFLUSH)
 			ppp_sync_flush_output(ap);
-		err = n_tty_ioctl_helper(tty, file, cmd, arg);
+		err = n_tty_ioctl_helper(tty, cmd, arg);
 		break;
 
 	case FIONREAD:
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 157b51ce9cc0..c98a04595084 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -2712,7 +2712,7 @@ static int gsmld_ioctl(struct tty_struct *tty, struct file *file,
 		base = mux_num_to_base(gsm);
 		return put_user(base + 1, (__u32 __user *)arg);
 	default:
-		return n_tty_ioctl_helper(tty, file, cmd, arg);
+		return n_tty_ioctl_helper(tty, cmd, arg);
 	}
 }
 
diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c
index 580a37b3fe1b..7e0884ecc74f 100644
--- a/drivers/tty/n_hdlc.c
+++ b/drivers/tty/n_hdlc.c
@@ -630,7 +630,7 @@ static int n_hdlc_tty_ioctl(struct tty_struct *tty, struct file *file,
 		fallthrough;	/* to default */
 
 	default:
-		error = n_tty_ioctl_helper(tty, file, cmd, arg);
+		error = n_tty_ioctl_helper(tty, cmd, arg);
 		break;
 	}
 	return error;
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index 797af5d46cbe..5be6d02dc690 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -2418,7 +2418,7 @@ static int n_tty_ioctl(struct tty_struct *tty, struct file *file,
 		up_write(&tty->termios_rwsem);
 		return put_user(retval, (unsigned int __user *) arg);
 	default:
-		return n_tty_ioctl_helper(tty, file, cmd, arg);
+		return n_tty_ioctl_helper(tty, cmd, arg);
 	}
 }
 
diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c
index 99a29d72d294..63181925ec1a 100644
--- a/drivers/tty/tty_ioctl.c
+++ b/drivers/tty/tty_ioctl.c
@@ -854,8 +854,8 @@ int tty_perform_flush(struct tty_struct *tty, unsigned long arg)
 }
 EXPORT_SYMBOL_GPL(tty_perform_flush);
 
-int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
-		       unsigned int cmd, unsigned long arg)
+int n_tty_ioctl_helper(struct tty_struct *tty, unsigned int cmd,
+		unsigned long arg)
 {
 	int retval;
 
diff --git a/include/linux/tty.h b/include/linux/tty.h
index 5e73f577c2b4..5dbd7c5afac7 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -407,8 +407,8 @@ static inline int tty_audit_push(void)
 #endif
 
 /* tty_ioctl.c */
-int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
-		unsigned int cmd, unsigned long arg);
+int n_tty_ioctl_helper(struct tty_struct *tty, unsigned int cmd,
+		unsigned long arg);
 
 /* vt.c */
 
diff --git a/net/nfc/nci/uart.c b/net/nfc/nci/uart.c
index 502e7a3f8948..9bdd9a7d187e 100644
--- a/net/nfc/nci/uart.c
+++ b/net/nfc/nci/uart.c
@@ -349,7 +349,7 @@ static int nci_uart_tty_ioctl(struct tty_struct *tty, struct file *file,
 			return -EBUSY;
 		break;
 	default:
-		err = n_tty_ioctl_helper(tty, file, cmd, arg);
+		err = n_tty_ioctl_helper(tty, cmd, arg);
 		break;
 	}
 
-- 
cgit v1.2.3


From 027b57170bf8bb6999a28e4a5f3d78bf1db0f90c Mon Sep 17 00:00:00 2001
From: Pali Rohár <pali@kernel.org>
Date: Sat, 2 Oct 2021 15:09:00 +0200
Subject: serial: core: Fix initializing and restoring termios speed
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Since commit edc6afc54968 ("tty: switch to ktermios and new framework")
termios speed is no longer stored only in c_cflag member but also in new
additional c_ispeed and c_ospeed members. If BOTHER flag is set in c_cflag
then termios speed is stored only in these new members.

Therefore to correctly restore termios speed it is required to store also
ispeed and ospeed members, not only cflag member.

In case only cflag member with BOTHER flag is restored then functions
tty_termios_baud_rate() and tty_termios_input_baud_rate() returns baudrate
stored in c_ospeed / c_ispeed member, which is zero as it was not restored
too. If reported baudrate is invalid (e.g. zero) then serial core functions
report fallback baudrate value 9600. So it means that in this case original
baudrate is lost and kernel changes it to value 9600.

Simple reproducer of this issue is to boot kernel with following command
line argument: "console=ttyXXX,86400" (where ttyXXX is the device name).
For speed 86400 there is no Bnnn constant and therefore kernel has to
represent this speed via BOTHER c_cflag. Which means that speed is stored
only in c_ospeed and c_ispeed members, not in c_cflag anymore.

If bootloader correctly configures serial device to speed 86400 then kernel
prints boot log to early console at speed speed 86400 without any issue.
But after kernel starts initializing real console device ttyXXX then speed
is changed to fallback value 9600 because information about speed was lost.

This patch fixes above issue by storing and restoring also ispeed and
ospeed members, which are required for BOTHER flag.

Fixes: edc6afc54968 ("[PATCH] tty: switch to ktermios and new framework")
Cc: stable@vger.kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20211002130900.9518-1-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/tty/serial/serial_core.c | 16 ++++++++++++++--
 include/linux/console.h          |  2 ++
 2 files changed, 16 insertions(+), 2 deletions(-)

(limited to 'include/linux')

diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 0e2e35ab64c7..1e738f265eea 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -222,7 +222,11 @@ static int uart_port_startup(struct tty_struct *tty, struct uart_state *state,
 	if (retval == 0) {
 		if (uart_console(uport) && uport->cons->cflag) {
 			tty->termios.c_cflag = uport->cons->cflag;
+			tty->termios.c_ispeed = uport->cons->ispeed;
+			tty->termios.c_ospeed = uport->cons->ospeed;
 			uport->cons->cflag = 0;
+			uport->cons->ispeed = 0;
+			uport->cons->ospeed = 0;
 		}
 		/*
 		 * Initialise the hardware port settings.
@@ -290,8 +294,11 @@ static void uart_shutdown(struct tty_struct *tty, struct uart_state *state)
 		/*
 		 * Turn off DTR and RTS early.
 		 */
-		if (uport && uart_console(uport) && tty)
+		if (uport && uart_console(uport) && tty) {
 			uport->cons->cflag = tty->termios.c_cflag;
+			uport->cons->ispeed = tty->termios.c_ispeed;
+			uport->cons->ospeed = tty->termios.c_ospeed;
+		}
 
 		if (!tty || C_HUPCL(tty))
 			uart_port_dtr_rts(uport, 0);
@@ -2094,8 +2101,11 @@ uart_set_options(struct uart_port *port, struct console *co,
 	 * Allow the setting of the UART parameters with a NULL console
 	 * too:
 	 */
-	if (co)
+	if (co) {
 		co->cflag = termios.c_cflag;
+		co->ispeed = termios.c_ispeed;
+		co->ospeed = termios.c_ospeed;
+	}
 
 	return 0;
 }
@@ -2229,6 +2239,8 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *uport)
 		 */
 		memset(&termios, 0, sizeof(struct ktermios));
 		termios.c_cflag = uport->cons->cflag;
+		termios.c_ispeed = uport->cons->ispeed;
+		termios.c_ospeed = uport->cons->ospeed;
 
 		/*
 		 * If that's unset, use the tty termios setting.
diff --git a/include/linux/console.h b/include/linux/console.h
index 20874db50bc8..a97f277cfdfa 100644
--- a/include/linux/console.h
+++ b/include/linux/console.h
@@ -149,6 +149,8 @@ struct console {
 	short	flags;
 	short	index;
 	int	cflag;
+	uint	ispeed;
+	uint	ospeed;
 	void	*data;
 	struct	 console *next;
 };
-- 
cgit v1.2.3


From e279317e9aeb11d8670e0a5acb10d50566eea9c9 Mon Sep 17 00:00:00 2001
From: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
Date: Fri, 15 Oct 2021 11:47:00 +0200
Subject: rpmsg: core: add API to get MTU

Return the rpmsg buffer MTU for sending message, so rpmsg users
can split a long message in several sub rpmsg buffers.

Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
Link: https://lore.kernel.org/r/20211015094701.5732-2-arnaud.pouliquen@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/rpmsg/rpmsg_core.c       | 21 +++++++++++++++++++++
 drivers/rpmsg/rpmsg_internal.h   |  2 ++
 drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++
 include/linux/rpmsg.h            | 10 ++++++++++
 4 files changed, 43 insertions(+)

(limited to 'include/linux')

diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
index 9151836190ce..d3eb60059ef1 100644
--- a/drivers/rpmsg/rpmsg_core.c
+++ b/drivers/rpmsg/rpmsg_core.c
@@ -327,6 +327,27 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
 }
 EXPORT_SYMBOL(rpmsg_trysend_offchannel);
 
+/**
+ * rpmsg_get_mtu() - get maximum transmission buffer size for sending message.
+ * @ept: the rpmsg endpoint
+ *
+ * This function returns maximum buffer size available for a single outgoing message.
+ *
+ * Return: the maximum transmission size on success and an appropriate error
+ * value on failure.
+ */
+
+ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
+{
+	if (WARN_ON(!ept))
+		return -EINVAL;
+	if (!ept->ops->get_mtu)
+		return -ENOTSUPP;
+
+	return ept->ops->get_mtu(ept);
+}
+EXPORT_SYMBOL(rpmsg_get_mtu);
+
 /*
  * match a rpmsg channel with a channel info struct.
  * this is used to make sure we're not creating rpmsg devices for channels
diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h
index a76c344253bf..b1245d3ed7c6 100644
--- a/drivers/rpmsg/rpmsg_internal.h
+++ b/drivers/rpmsg/rpmsg_internal.h
@@ -53,6 +53,7 @@ struct rpmsg_device_ops {
  * @trysendto:		see @rpmsg_trysendto(), optional
  * @trysend_offchannel:	see @rpmsg_trysend_offchannel(), optional
  * @poll:		see @rpmsg_poll(), optional
+ * @get_mtu:		see @rpmsg_get_mtu(), optional
  *
  * Indirection table for the operations that a rpmsg backend should implement.
  * In addition to @destroy_ept, the backend must at least implement @send and
@@ -72,6 +73,7 @@ struct rpmsg_endpoint_ops {
 			     void *data, int len);
 	__poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
 			     poll_table *wait);
+	ssize_t (*get_mtu)(struct rpmsg_endpoint *ept);
 };
 
 struct device *rpmsg_find_device(struct device *parent,
diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index 8e49a3bacfc7..05fd06fc67e9 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -149,6 +149,7 @@ static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data,
 				  int len, u32 dst);
 static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
 					   u32 dst, void *data, int len);
+static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept);
 static struct rpmsg_device *__rpmsg_create_channel(struct virtproc_info *vrp,
 						   struct rpmsg_channel_info *chinfo);
 
@@ -160,6 +161,7 @@ static const struct rpmsg_endpoint_ops virtio_endpoint_ops = {
 	.trysend = virtio_rpmsg_trysend,
 	.trysendto = virtio_rpmsg_trysendto,
 	.trysend_offchannel = virtio_rpmsg_trysend_offchannel,
+	.get_mtu = virtio_rpmsg_get_mtu,
 };
 
 /**
@@ -696,6 +698,14 @@ static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
 	return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false);
 }
 
+static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept)
+{
+	struct rpmsg_device *rpdev = ept->rpdev;
+	struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev);
+
+	return vch->vrp->buf_size - sizeof(struct rpmsg_hdr);
+}
+
 static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev,
 			     struct rpmsg_hdr *msg, unsigned int len)
 {
diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
index d97dcd049f18..990b80fb49ad 100644
--- a/include/linux/rpmsg.h
+++ b/include/linux/rpmsg.h
@@ -186,6 +186,8 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
 __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp,
 			poll_table *wait);
 
+ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept);
+
 #else
 
 static inline int rpmsg_register_device(struct rpmsg_device *rpdev)
@@ -296,6 +298,14 @@ static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept,
 	return 0;
 }
 
+static inline ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return -ENXIO;
+}
+
 #endif /* IS_ENABLED(CONFIG_RPMSG) */
 
 /* use a macro to avoid include chaining to get THIS_MODULE */
-- 
cgit v1.2.3


From cc8d7b4aea79df7cb45b74f9bc5b8a8bd2ed4c07 Mon Sep 17 00:00:00 2001
From: Anssi Hannula <anssi.hannula@bitwise.fi>
Date: Wed, 27 Oct 2021 13:21:24 +0300
Subject: tty: Fix extra "not" in TTY_DRIVER_REAL_RAW description

TTY_DRIVER_REAL_RAW flag (which is always set for e.g. serial ports)
documentation says that driver must always set special character
handling flags in certain conditions.

However, as the following sentence makes clear, what is actually
intended is the opposite.

Fix that by removing the unintended double negation.

Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Link: https://lore.kernel.org/r/20211027102124.3049414-1-anssi.hannula@bitwise.fi
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 include/linux/tty_driver.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'include/linux')

diff --git a/include/linux/tty_driver.h b/include/linux/tty_driver.h
index 29e1cf178afb..795b94ccdeb6 100644
--- a/include/linux/tty_driver.h
+++ b/include/linux/tty_driver.h
@@ -360,7 +360,7 @@ static inline void tty_set_operations(struct tty_driver *driver,
  * 	Used for PTY's, in particular.
  * 
  * TTY_DRIVER_REAL_RAW --- if set, indicates that the driver will
- * 	guarantee never not to set any special character handling
+ * 	guarantee never to set any special character handling
  * 	flags if ((IGNBRK || (!BRKINT && !PARMRK)) && (IGNPAR ||
  * 	!INPCK)).  That is, if there is no reason for the driver to
  * 	send notifications of parity and break characters up to the
-- 
cgit v1.2.3