[PATCH] Serial: Adjust serial locking

This patch changes the way serial ports are locked when getting modem
status.  This change is necessary because we will need to atomically
read the modem status and take action depending on the CTS status.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

drivers/serial/serial_txx9.c

@@ -442,13 +442,10 @@ static unsigned int serial_txx9_tx_empty(struct uart_port *port)
 static unsigned int serial_txx9_get_mctrl(struct uart_port *port)
 {
 	struct uart_txx9_port *up = (struct uart_txx9_port *)port;
-	unsigned long flags;
 	unsigned int ret;
 
-	spin_lock_irqsave(&up->port.lock, flags);
 	ret =  ((sio_in(up, TXX9_SIFLCR) & TXX9_SIFLCR_RTSSC) ? 0 : TIOCM_RTS)
 		| ((sio_in(up, TXX9_SICISR) & TXX9_SICISR_CTSS) ? 0 : TIOCM_CTS);
-	spin_unlock_irqrestore(&up->port.lock, flags);
 
 	return ret;
 }