tty: mxser: fix TIOCSSERIAL jiffies conversions

The port close_delay and closing wait parameters set by TIOCSSERIAL are
specified in jiffies, while the values returned by TIOCGSERIAL are
specified in centiseconds.

Add the missing conversions so that TIOCSSERIAL works as expected also
when HZ is not 100.

Cc: stable@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210407102334.32361-14-johan@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/mxser.c

@@ -1208,19 +1208,26 @@ static int mxser_get_serial_info(struct tty_struct *tty,
 {
 	struct mxser_port *info = tty->driver_data;
 	struct tty_port *port = &info->port;
+	unsigned int closing_wait, close_delay;
 
 	if (tty->index == MXSER_PORTS)
 		return -ENOTTY;
 
 	mutex_lock(&port->mutex);
+
+	close_delay = jiffies_to_msecs(info->port.close_delay) / 10;
+	closing_wait = info->port.closing_wait;
+	if (closing_wait != ASYNC_CLOSING_WAIT_NONE)
+		closing_wait = jiffies_to_msecs(closing_wait) / 10;
+
 	ss->type = info->type,
 	ss->line = tty->index,
 	ss->port = info->ioaddr,
 	ss->irq = info->board->irq,
 	ss->flags = info->port.flags,
 	ss->baud_base = info->baud_base,
-	ss->close_delay = info->port.close_delay,
-	ss->closing_wait = info->port.closing_wait,
+	ss->close_delay = close_delay;
+	ss->closing_wait = closing_wait;
 	ss->custom_divisor = info->custom_divisor,
 	mutex_unlock(&port->mutex);
 	return 0;
@@ -1233,7 +1240,7 @@ static int mxser_set_serial_info(struct tty_struct *tty,
 	struct tty_port *port = &info->port;
 	speed_t baud;
 	unsigned long sl_flags;
-	unsigned int flags;
+	unsigned int flags, close_delay, closing_wait;
 	int retval = 0;
 
 	if (tty->index == MXSER_PORTS)
@@ -1255,9 +1262,14 @@ static int mxser_set_serial_info(struct tty_struct *tty,
 
 	flags = port->flags & ASYNC_SPD_MASK;
 
+	close_delay = msecs_to_jiffies(ss->close_delay * 10);
+	closing_wait = ss->closing_wait;
+	if (closing_wait != ASYNC_CLOSING_WAIT_NONE)
+		closing_wait = msecs_to_jiffies(closing_wait * 10);
+
 	if (!capable(CAP_SYS_ADMIN)) {
 		if ((ss->baud_base != info->baud_base) ||
-				(ss->close_delay != info->port.close_delay) ||
+				(close_delay != info->port.close_delay) ||
 				((ss->flags & ~ASYNC_USR_MASK) != (info->port.flags & ~ASYNC_USR_MASK))) {
 			mutex_unlock(&port->mutex);
 			return -EPERM;
@@ -1271,8 +1283,8 @@ static int mxser_set_serial_info(struct tty_struct *tty,
 		 */
 		port->flags = ((port->flags & ~ASYNC_FLAGS) |
 				(ss->flags & ASYNC_FLAGS));
-		port->close_delay = ss->close_delay * HZ / 100;
-		port->closing_wait = ss->closing_wait * HZ / 100;
+		port->close_delay = close_delay;
+		port->closing_wait = closing_wait;
 		if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST &&
 				(ss->baud_base != info->baud_base ||
 				ss->custom_divisor !=