diff --git a/drivers/staging/comedi/drivers/dt9812.c b/drivers/staging/comedi/drivers/dt9812.c
index 9f165f1cefa56..634f57730c1e0 100644
--- a/drivers/staging/comedi/drivers/dt9812.c
+++ b/drivers/staging/comedi/drivers/dt9812.c
@@ -835,11 +835,8 @@ static void dt9812_detach(struct comedi_device *dev)
 	if (!devpriv)
 		return;
 
-	mutex_lock(&devpriv->mut);
-
+	mutex_destroy(&devpriv->mut);
 	usb_set_intfdata(intf, NULL);
-
-	mutex_unlock(&devpriv->mut);
 }
 
 static struct comedi_driver dt9812_driver = {