- The Frame Interval Monitor could be exported to v4l2-core for
  general use.

- This media driver supports inheriting V4L2 controls to the
  video capture devices, from the subdevices in the capture device's
  pipeline. The controls for each capture device are updated in the
  link_notify callback when the pipeline is modified. This feature should be
  removed, userspace should use the subdev-based userspace API instead.

- Similarly to the legacy control handling, legacy format handling where
  formats on the video nodes are influenced by the active format of the
  connected subdev should be removed.