From: Jiun Yu
Samsung Exynos tv subsystem is composed of video processor, mixer, HDMI Tx
and analog TV. Each h/w IP becomes a entity and also inputs of video and graphic
layers become entities in media controller framework like below figure
> 5. Mixer & Video Processor driver. It is called 's5p-mixer' because of
> historical reasons. It was decided combine VP and MXR drivers into one because
> of shared interrupt and very similar interface via V4L2 nodes. The driver is a
> realization of many-to-many relation between multiple input
