spin_lock_irqsave(&tport->tp_lock, flags);
 
        if (tport->tp_read_urb_state == TI_READ_URB_STOPPED) {
+               tport->tp_read_urb_state = TI_READ_URB_RUNNING;
                urb = tport->tp_port->read_urb;
+               spin_unlock_irqrestore(&tport->tp_lock, flags);
                urb->complete = ti_bulk_in_callback;
                urb->context = tport;
                urb->dev = tport->tp_port->serial->dev;
                status = usb_submit_urb(urb, GFP_KERNEL);
+       } else  {
+               tport->tp_read_urb_state = TI_READ_URB_RUNNING;
+               spin_unlock_irqrestore(&tport->tp_lock, flags);
        }
-       tport->tp_read_urb_state = TI_READ_URB_RUNNING;
-
-       spin_unlock_irqrestore(&tport->tp_lock, flags);
 
        return status;
 }