tty: Make ->set_termios() old ktermios const

There should be no reason to adjust old ktermios which is going to get
discarded anyway.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220816115739.10928-9-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

7 files changed, 20 insertions, 15 deletions

diff --git a/drivers/tty/amiserial.c b/drivers/tty/amiserial.c
index 81e7f64c1739..f52266766df9 100644
--- a/drivers/tty/amiserial.c
+++ b/drivers/tty/amiserial.c
@@ -94,7 +94,7 @@ static struct tty_driver *serial_driver;
 static unsigned char current_ctl_bits;
 
 static void change_speed(struct tty_struct *tty, struct serial_state *info,
-		struct ktermios *old);
+			 const struct ktermios *old);
 static void rs_wait_until_sent(struct tty_struct *tty, int timeout);
 
 
@@ -566,7 +566,7 @@ static void shutdown(struct tty_struct *tty, struct serial_state *info)
  * the specified baud rate for a serial port.
  */
 static void change_speed(struct tty_struct *tty, struct serial_state *info,
-			 struct ktermios *old_termios)
+			 const struct ktermios *old_termios)
 {
 	struct tty_port *port = &info->tport;
 	int	quot = 0, baud_base, baud;
@@ -1169,7 +1169,7 @@ static int rs_ioctl(struct tty_struct *tty,
 	return 0;
 }
 
-static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
+static void rs_set_termios(struct tty_struct *tty, const struct ktermios *old_termios)
 {
 	struct serial_state *info = tty->driver_data;
 	unsigned long flags;
diff --git a/drivers/tty/moxa.c b/drivers/tty/moxa.c
index f3c72ab1476c..35b6fddf0341 100644
--- a/drivers/tty/moxa.c
+++ b/drivers/tty/moxa.c
@@ -491,7 +491,7 @@ static int moxa_write(struct tty_struct *, const unsigned char *, int);
 static unsigned int moxa_write_room(struct tty_struct *);
 static void moxa_flush_buffer(struct tty_struct *);
 static unsigned int moxa_chars_in_buffer(struct tty_struct *);
-static void moxa_set_termios(struct tty_struct *, struct ktermios *);
+static void moxa_set_termios(struct tty_struct *, const struct ktermios *);
 static void moxa_stop(struct tty_struct *);
 static void moxa_start(struct tty_struct *);
 static void moxa_hangup(struct tty_struct *);
@@ -499,7 +499,7 @@ static int moxa_tiocmget(struct tty_struct *tty);
 static int moxa_tiocmset(struct tty_struct *tty,
 			 unsigned int set, unsigned int clear);
 static void moxa_poll(struct timer_list *);
-static void moxa_set_tty_param(struct tty_struct *, struct ktermios *);
+static void moxa_set_tty_param(struct tty_struct *, const struct ktermios *);
 static void moxa_shutdown(struct tty_port *);
 static int moxa_carrier_raised(struct tty_port *);
 static void moxa_dtr_rts(struct tty_port *, int);
@@ -1602,7 +1602,7 @@ static int moxa_tiocmset(struct tty_struct *tty,
 }
 
 static void moxa_set_termios(struct tty_struct *tty,
-		struct ktermios *old_termios)
+		             const struct ktermios *old_termios)
 {
 	struct moxa_port *ch = tty->driver_data;
 
@@ -1761,7 +1761,8 @@ static void moxa_poll(struct timer_list *unused)
 
 /******************************************************************************/
 
-static void moxa_set_tty_param(struct tty_struct *tty, struct ktermios *old_termios)
+static void moxa_set_tty_param(struct tty_struct *tty,
+			       const struct ktermios *old_termios)
 {
 	register struct ktermios *ts = &tty->termios;
 	struct moxa_port *ch = tty->driver_data;
diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index 70b982b2c6b2..3413bd77beed 100644
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -571,7 +571,8 @@ static void mxser_handle_cts(struct tty_struct *tty, struct mxser_port *info,
  * This routine is called to set the UART divisor registers to match
  * the specified baud rate for a serial port.
  */
-static void mxser_change_speed(struct tty_struct *tty, struct ktermios *old_termios)
+static void mxser_change_speed(struct tty_struct *tty,
+			       const struct ktermios *old_termios)
 {
 	struct mxser_port *info = tty->driver_data;
 	unsigned cflag, cval;
@@ -1348,7 +1349,8 @@ static void mxser_start(struct tty_struct *tty)
 	spin_unlock_irqrestore(&info->slock, flags);
 }
 
-static void mxser_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
+static void mxser_set_termios(struct tty_struct *tty,
+			      const struct ktermios *old_termios)
 {
 	struct mxser_port *info = tty->driver_data;
 	unsigned long flags;
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index caa5c14ed57f..97cd8d67c866 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -3647,7 +3647,8 @@ static int gsmtty_ioctl(struct tty_struct *tty,
 	}
 }
 
-static void gsmtty_set_termios(struct tty_struct *tty, struct ktermios *old)
+static void gsmtty_set_termios(struct tty_struct *tty,
+			       const struct ktermios *old)
 {
 	struct gsm_dlci *dlci = tty->driver_data;
 	if (dlci->state == DLCI_CLOSED)
diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index 752dab3356d7..07394fdaf522 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -240,7 +240,7 @@ out:
 }
 
 static void pty_set_termios(struct tty_struct *tty,
-					struct ktermios *old_termios)
+			    const struct ktermios *old_termios)
 {
 	/* See if packet mode change of state. */
 	if (tty->link && tty->link->ctrl.packet) {
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 04c0bb18cfd3..c7113182275a 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -49,7 +49,7 @@ static struct lock_class_key port_lock_key;
 #define RS485_MAX_RTS_DELAY	100 /* msecs */
 
 static void uart_change_speed(struct tty_struct *tty, struct uart_state *state,
-					struct ktermios *old_termios);
+			      const struct ktermios *old_termios);
 static void uart_wait_until_sent(struct tty_struct *tty, int timeout);
 static void uart_change_pm(struct uart_state *state,
 			   enum uart_pm_state pm_state);
@@ -492,7 +492,7 @@ EXPORT_SYMBOL(uart_get_divisor);
 
 /* Caller holds port mutex */
 static void uart_change_speed(struct tty_struct *tty, struct uart_state *state,
-					struct ktermios *old_termios)
+			      const struct ktermios *old_termios)
 {
 	struct uart_port *uport = uart_port_check(state);
 	struct ktermios *termios;
@@ -1619,7 +1619,7 @@ static void uart_set_ldisc(struct tty_struct *tty)
 }
 
 static void uart_set_termios(struct tty_struct *tty,
-						struct ktermios *old_termios)
+			     const struct ktermios *old_termios)
 {
 	struct uart_state *state = tty->driver_data;
 	struct uart_port *uport;
diff --git a/drivers/tty/synclink_gt.c b/drivers/tty/synclink_gt.c
index 9bc2a9265277..4a003e929776 100644
--- a/drivers/tty/synclink_gt.c
+++ b/drivers/tty/synclink_gt.c
@@ -707,7 +707,8 @@ static void hangup(struct tty_struct *tty)
 	wake_up_interruptible(&info->port.open_wait);
 }
 
-static void set_termios(struct tty_struct *tty, struct ktermios *old_termios)
+static void set_termios(struct tty_struct *tty,
+			const struct ktermios *old_termios)
 {
 	struct slgt_info *info = tty->driver_data;
 	unsigned long flags;