media: rkisp1: params: Fix and simplify (un)registration

The rkisp1_params_register() and rkisp1_params_unregister() functions
don't destroy the mutex (in the error path for the former). Fix this,
simplify error handling at registration time as media_entity_cleanup()
can be called on an uninitialized entity, and make
rkisp1_params_unregister() safe to be called on an unregistered params
node to prepare for simplification of error handling at probe time.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/platform/rockchip/rkisp1/rkisp1-params.c

@@ -1844,16 +1844,20 @@ int rkisp1_params_register(struct rkisp1_device *rkisp1)
 	node->pad.flags = MEDIA_PAD_FL_SOURCE;
 	ret = media_entity_pads_init(&vdev->entity, 1, &node->pad);
 	if (ret)
-		return ret;
+		goto error;
+
 	ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
 	if (ret) {
 		dev_err(rkisp1->dev,
 			"failed to register %s, ret=%d\n", vdev->name, ret);
-		goto err_cleanup_media_entity;
+		goto error;
 	}
+
 	return 0;
-err_cleanup_media_entity:
+
+error:
 	media_entity_cleanup(&vdev->entity);
+	mutex_destroy(&node->vlock);
 	return ret;
 }
 
@@ -1863,6 +1867,10 @@ void rkisp1_params_unregister(struct rkisp1_device *rkisp1)
 	struct rkisp1_vdev_node *node = &params->vnode;
 	struct video_device *vdev = &node->vdev;
 
+	if (!video_is_registered(vdev))
+		return;
+
 	vb2_video_unregister_device(vdev);
 	media_entity_cleanup(&vdev->entity);
+	mutex_destroy(&node->vlock);
 }