tty: make tty_operations::chars_in_buffer return uint

tty_operations::chars_in_buffer is another hook which is expected to
return values >= 0. So make it explicit by the return type too -- use
unsigned int.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Acked-by: David Sterba <dsterba@suse.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Cc: Jens Taprogge <jens.taprogge@taprogge.org>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Lin <dtwlin@gmail.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: Alex Elder <elder@kernel.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Oliver Neukum <oneukum@suse.com>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Mathias Nyman <mathias.nyman@intel.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Link: https://lore.kernel.org/r/20210505091928.22010-27-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

5 files changed, 8 insertions, 10 deletions

diff --git a/drivers/s390/char/con3215.c b/drivers/s390/char/con3215.c
index c9fd4a05931a..8821927ef875 100644
--- a/drivers/s390/char/con3215.c
+++ b/drivers/s390/char/con3215.c
@@ -980,7 +980,7 @@ static void tty3215_flush_chars(struct tty_struct *tty)
 /*
  * Returns the number of characters in the output buffer
  */
-static int tty3215_chars_in_buffer(struct tty_struct *tty)
+static unsigned int tty3215_chars_in_buffer(struct tty_struct *tty)
 {
 	struct raw3215_info *raw = tty->driver_data;
 
diff --git a/drivers/s390/char/sclp_rw.c b/drivers/s390/char/sclp_rw.c
index d6c84e354df5..5a1bf6eaa9d9 100644
--- a/drivers/s390/char/sclp_rw.c
+++ b/drivers/s390/char/sclp_rw.c
@@ -325,10 +325,10 @@ sclp_buffer_space(struct sclp_buffer *buffer)
 /*
  * Return number of characters in buffer
  */
-int
+unsigned int
 sclp_chars_in_buffer(struct sclp_buffer *buffer)
 {
-	int count;
+	unsigned int count;
 
 	count = buffer->char_sum;
 	if (buffer->current_line != NULL)
diff --git a/drivers/s390/char/sclp_rw.h b/drivers/s390/char/sclp_rw.h
index 93d706e4935c..b4506be79246 100644
--- a/drivers/s390/char/sclp_rw.h
+++ b/drivers/s390/char/sclp_rw.h
@@ -86,7 +86,7 @@ void *sclp_unmake_buffer(struct sclp_buffer *);
 int sclp_buffer_space(struct sclp_buffer *);
 int sclp_write(struct sclp_buffer *buffer, const unsigned char *, int);
 int sclp_emit_buffer(struct sclp_buffer *,void (*)(struct sclp_buffer *,int));
-int sclp_chars_in_buffer(struct sclp_buffer *);
+unsigned int sclp_chars_in_buffer(struct sclp_buffer *);
 
 #ifdef CONFIG_SCLP_CONSOLE
 void sclp_console_pm_event(enum sclp_pm_event sclp_pm_event);
diff --git a/drivers/s390/char/sclp_tty.c b/drivers/s390/char/sclp_tty.c
index ea1e43fd16bc..162127ff7845 100644
--- a/drivers/s390/char/sclp_tty.c
+++ b/drivers/s390/char/sclp_tty.c
@@ -280,16 +280,15 @@ sclp_tty_flush_chars(struct tty_struct *tty)
  * characters in the write buffer (will not be written as long as there is a
  * final line feed missing).
  */
-static int
+static unsigned int
 sclp_tty_chars_in_buffer(struct tty_struct *tty)
 {
 	unsigned long flags;
 	struct list_head *l;
 	struct sclp_buffer *t;
-	int count;
+	unsigned int count = 0;
 
 	spin_lock_irqsave(&sclp_tty_lock, flags);
-	count = 0;
 	if (sclp_ttybuf != NULL)
 		count = sclp_chars_in_buffer(sclp_ttybuf);
 	list_for_each(l, &sclp_tty_outqueue) {
diff --git a/drivers/s390/char/sclp_vt220.c b/drivers/s390/char/sclp_vt220.c
index b621adee35f0..24eb3a0b0a9a 100644
--- a/drivers/s390/char/sclp_vt220.c
+++ b/drivers/s390/char/sclp_vt220.c
@@ -629,16 +629,15 @@ sclp_vt220_write_room(struct tty_struct *tty)
 /*
  * Return number of buffered chars.
  */
-static int
+static unsigned int
 sclp_vt220_chars_in_buffer(struct tty_struct *tty)
 {
 	unsigned long flags;
 	struct list_head *l;
 	struct sclp_vt220_request *r;
-	int count;
+	unsigned int count = 0;
 
 	spin_lock_irqsave(&sclp_vt220_lock, flags);
-	count = 0;
 	if (sclp_vt220_current_request != NULL)
 		count = sclp_vt220_chars_stored(sclp_vt220_current_request);
 	list_for_each(l, &sclp_vt220_outqueue) {