1 files changed, 13 insertions, 9 deletions

diff --git a/drivers/usb/serial/visor.c b/drivers/usb/serial/visor.c
index 7ee087fed913..c2347995c786 100644
--- a/drivers/usb/serial/visor.c
+++ b/drivers/usb/serial/visor.c
@@ -349,16 +349,20 @@ static void visor_close (struct usb_serial_port *port, struct file * filp)
         usb_kill_urb(port->read_urb);
         usb_kill_urb(port->interrupt_in_urb);
 
-        /* Try to send shutdown message, if the device is gone, this will just fail. */
-        transfer_buffer =  kmalloc (0x12, GFP_KERNEL);
-        if (transfer_buffer) {
-                usb_control_msg (port->serial->dev,
-                                 usb_rcvctrlpipe(port->serial->dev, 0),
-                                 VISOR_CLOSE_NOTIFICATION, 0xc2,
-                                 0x0000, 0x0000, 
-                                 transfer_buffer, 0x12, 300);
-                kfree (transfer_buffer);
+        mutex_lock(&port->serial->disc_mutex);
+        if (!port->serial->disconnected) {
+                /* Try to send shutdown message, unless the device is gone */
+                transfer_buffer =  kmalloc (0x12, GFP_KERNEL);
+                if (transfer_buffer) {
+                        usb_control_msg (port->serial->dev,
+                                         usb_rcvctrlpipe(port->serial->dev, 0),
+                                         VISOR_CLOSE_NOTIFICATION, 0xc2,
+                                         0x0000, 0x0000,
+                                         transfer_buffer, 0x12, 300);
+                        kfree (transfer_buffer);
+                }
         }
+        mutex_lock(&port->serial->disc_mutex);
 
         if (stats)
                 dev_info(&port->dev, "Bytes In = %d  Bytes Out = %d\n",