The subdev userspace API isn't serialized in the core, serialize access
to formats and selection rectangles in the driver.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: NNiklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>