tty/serial_core: Introduce lock mechanism for RS485

Introduce an homogeneous lock system between setting and using the rs485
data of the uart_port.

This patch should not be split into multiple ones in order to avoid
leaving the tree in an unstable state.

Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Suggested-by: Alan Cox <alan@linux.intel.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 0 insertions, 3 deletions

diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 050d1b5c7b36..e0bec06a5f60 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -1360,12 +1360,10 @@ static int
 serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
 {
         struct uart_omap_port *up = to_uart_omap_port(port);
-        unsigned long flags;
         unsigned int mode;
         int val;
 
         pm_runtime_get_sync(up->dev);
-        spin_lock_irqsave(&up->port.lock, flags);
 
         /* Disable interrupts from this port */
         mode = up->ier;
@@ -1401,7 +1399,6 @@ serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
                 serial_out(up, UART_OMAP_SCR, up->scr);
         }
 
-        spin_unlock_irqrestore(&up->port.lock, flags);
         pm_runtime_mark_last_busy(up->dev);
         pm_runtime_put_autosuspend(up->dev);