diff --git a/drivers/usb/serial/io_ti.c b/drivers/usb/serial/io_ti.c
index 58184f3de6867bfa9ebbbc6d6afbe074d80a8f12..82afc4d6a327d6bdbebc4707507684c966f11f9f 100644
--- a/drivers/usb/serial/io_ti.c
+++ b/drivers/usb/serial/io_ti.c
@@ -530,6 +530,9 @@ static void chase_port(struct edgeport_port *port, unsigned long timeout,
 	wait_queue_t wait;
 	unsigned long flags;
 
+	if (!tty)
+		return;
+
 	if (!timeout)
 		timeout = (HZ * EDGE_CLOSING_WAIT)/100;