[media] v4l: subdev: Add new file operations

V4L2 sub-devices store pad formats and crop settings in the file handle.
To let drivers initialize those settings properly, add an open operation
that is called when the subdev is opened as well as a corresponding
close operation.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/v4l2-subdev.c b/drivers/media/video/v4l2-subdev.c
index 6cef6ad..bc763db 100644
--- a/drivers/media/video/v4l2-subdev.c
+++ b/drivers/media/video/v4l2-subdev.c
@@ -61,7 +61,7 @@
 	struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev);
 	struct v4l2_subdev_fh *subdev_fh;
 #if defined(CONFIG_MEDIA_CONTROLLER)
-	struct media_entity *entity;
+	struct media_entity *entity = NULL;
 #endif
 	int ret;
 
@@ -101,9 +101,19 @@
 	}
 #endif
 
+	if (sd->internal_ops && sd->internal_ops->open) {
+		ret = sd->internal_ops->open(sd, subdev_fh);
+		if (ret < 0)
+			goto err;
+	}
+
 	return 0;
 
 err:
+#if defined(CONFIG_MEDIA_CONTROLLER)
+	if (entity)
+		media_entity_put(entity);
+#endif
 	v4l2_fh_del(&subdev_fh->vfh);
 	v4l2_fh_exit(&subdev_fh->vfh);
 	subdev_fh_free(subdev_fh);
@@ -114,13 +124,13 @@
 
 static int subdev_close(struct file *file)
 {
-#if defined(CONFIG_MEDIA_CONTROLLER)
 	struct video_device *vdev = video_devdata(file);
 	struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev);
-#endif
 	struct v4l2_fh *vfh = file->private_data;
 	struct v4l2_subdev_fh *subdev_fh = to_v4l2_subdev_fh(vfh);
 
+	if (sd->internal_ops && sd->internal_ops->close)
+		sd->internal_ops->close(sd, subdev_fh);
 #if defined(CONFIG_MEDIA_CONTROLLER)
 	if (sd->v4l2_dev->mdev)
 		media_entity_put(&sd->entity);