usb_serial: Kill port mutex

The tty port has a port mutex used for all the port related locking so we
don't need the one in the USB serial layer any more.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/serial/opticon.c

@@ -501,12 +501,12 @@ static int opticon_resume(struct usb_interface *intf)
 	struct usb_serial_port *port = serial->port[0];
 	int result;
 
-	mutex_lock(&port->mutex);
+	mutex_lock(&port->port.mutex);
 	if (port->port.count)
 		result = usb_submit_urb(priv->bulk_read_urb, GFP_NOIO);
 	else
 		result = 0;
-	mutex_unlock(&port->mutex);
+	mutex_unlock(&port->port.mutex);
 	return result;
 }
 

drivers/usb/serial/usb-serial.c

@@ -897,7 +897,6 @@ int usb_serial_probe(struct usb_interface *interface,
 		spin_lock_init(&port->lock);
 		/* Keep this for private driver use for the moment but
 		   should probably go away */
-		mutex_init(&port->mutex);
 		INIT_WORK(&port->work, usb_serial_port_work);
 		serial->port[i] = port;
 		port->dev.parent = &interface->dev;

include/linux/usb/serial.h

@@ -39,8 +39,6 @@ enum port_dev_state {
  * @serial: pointer back to the struct usb_serial owner of this port.
  * @port: pointer to the corresponding tty_port for this port.
  * @lock: spinlock to grab when updating portions of this structure.
- * @mutex: mutex used to synchronize serial_open() and serial_close()
- *	access for this port.
  * @number: the number of the port (the minor number).
  * @interrupt_in_buffer: pointer to the interrupt in buffer for this port.
  * @interrupt_in_urb: pointer to the interrupt in struct urb for this port.
@@ -77,7 +75,6 @@ struct usb_serial_port {
 	struct usb_serial	*serial;
 	struct tty_port		port;
 	spinlock_t		lock;
-	struct mutex            mutex;
 	unsigned char		number;
 
 	unsigned char		*interrupt_in_buffer;