--- zzzz-none-000/linux-2.6.32.61/drivers/usb/serial/garmin_gps.c	2013-06-10 09:43:48.000000000 +0000
+++ virian-300e-630/linux-2.6.32.61/drivers/usb/serial/garmin_gps.c	2013-02-11 16:39:19.000000000 +0000
@@ -974,7 +974,10 @@
 	if (!serial)
 		return;
 
-	garmin_clear(garmin_data_p);
+	mutex_lock(&port->serial->disc_mutex);
+
+	if (!port->serial->disconnected)
+		garmin_clear(garmin_data_p);
 
 	/* shutdown our urbs */
 	usb_kill_urb(port->read_urb);
@@ -983,6 +986,8 @@
 	/* keep reset state so we know that we must start a new session */
 	if (garmin_data_p->state != STATE_RESET)
 		garmin_data_p->state = STATE_DISCONNECTED;
+
+	mutex_unlock(&port->serial->disc_mutex);
 }