diff --git a/drivers/staging/comedi/drivers/usbduxfast.c b/drivers/staging/comedi/drivers/usbduxfast.c
index 4c86a9a913cd..c6b2a6582127 100644
--- a/drivers/staging/comedi/drivers/usbduxfast.c
+++ b/drivers/staging/comedi/drivers/usbduxfast.c
@@ -998,16 +998,10 @@ static void usbduxfast_detach(struct comedi_device *dev)
 		usb_kill_urb(devpriv->urb);
 
 		kfree(devpriv->inbuf);
-		devpriv->inbuf = NULL;
-
 		usb_free_urb(devpriv->urb);
-		devpriv->urb = NULL;
 	}
 
 	kfree(devpriv->duxbuf);
-	devpriv->duxbuf = NULL;
-
-	devpriv->ai_cmd_running = 0;
 
 	up(&devpriv->sem);
 }