diff --git a/[refs] b/[refs]
index 96ee7393ced4..cde84f995931 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: de0c8cb314cc737c47a00de33cd6246accf94192
+refs/heads/master: 24fcc7c8cd0fcabcf37d455abe3501b3196fcf64
diff --git a/trunk/drivers/serial/serial_core.c b/trunk/drivers/serial/serial_core.c
index 2379045e0871..0603e0d46d33 100644
--- a/trunk/drivers/serial/serial_core.c
+++ b/trunk/drivers/serial/serial_core.c
@@ -1506,12 +1506,10 @@ static int uart_carrier_raised(struct tty_port *port)
 	struct uart_state *state = container_of(port, struct uart_state, port);
 	struct uart_port *uport = state->uart_port;
 	int mctrl;
-	mutex_lock(&port->mutex);
 	spin_lock_irq(&uport->lock);
 	uport->ops->enable_ms(uport);
 	mctrl = uport->ops->get_mctrl(uport);
 	spin_unlock_irq(&uport->lock);
-	mutex_unlock(&port->mutex);
 	if (mctrl & TIOCM_CAR)
 		return 1;
 	return 0;
@@ -1521,12 +1519,11 @@ static void uart_dtr_rts(struct tty_port *port, int onoff)
 {
 	struct uart_state *state = container_of(port, struct uart_state, port);
 	struct uart_port *uport = state->uart_port;
-	mutex_lock(&port->mutex);
+
 	if (onoff)
 		uart_set_mctrl(uport, TIOCM_DTR | TIOCM_RTS);
 	else
 		uart_clear_mctrl(uport, TIOCM_DTR | TIOCM_RTS);
-	mutex_unlock(&port->mutex);
 }
 
 /*