diff --git a/drivers/media/usb/rainshadow-cec/rainshadow-cec.c b/drivers/media/usb/rainshadow-cec/rainshadow-cec.c
index 9ddd6a99f066bd557787af2e708ba413a6d920e5..8d3ca2c8b20fb43d8112b198b524cfce09be868e 100644
--- a/drivers/media/usb/rainshadow-cec/rainshadow-cec.c
+++ b/drivers/media/usb/rainshadow-cec/rainshadow-cec.c
@@ -337,6 +337,7 @@ static int rain_connect(struct serio *serio, struct serio_driver *drv)
 	serio_set_drvdata(serio, rain);
 	INIT_WORK(&rain->work, rain_irq_work_handler);
 	mutex_init(&rain->write_lock);
+	spin_lock_init(&rain->buf_lock);
 
 	err = serio_open(serio, drv);
 	if (err)