diff --git a/drivers/usb/serial/quatech2.c b/drivers/usb/serial/quatech2.c
index 659cb8606bd953a7585a013beeb3dc3989400a14..5709cc93b0837a0b73a8acec627caa05e27c9b64 100644
--- a/drivers/usb/serial/quatech2.c
+++ b/drivers/usb/serial/quatech2.c
@@ -408,16 +408,12 @@ static void qt2_close(struct usb_serial_port *port)
 {
 	struct usb_serial *serial;
 	struct qt2_port_private *port_priv;
-	unsigned long flags;
 	int i;
 
 	serial = port->serial;
 	port_priv = usb_get_serial_port_data(port);
 
-	spin_lock_irqsave(&port_priv->urb_lock, flags);
 	usb_kill_urb(port_priv->write_urb);
-	port_priv->urb_in_use = false;
-	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
 
 	/* flush the port transmit buffer */
 	i = usb_control_msg(serial->dev,