Provide v4l2_subdevs with v4l2_event support. Subdev drivers only need very
little to support events.
Signed-off-by: NSakari Ailus <sakari.ailus@iki.fi>
Signed-off-by: NDavid Cohen <dacohen@gmail.com>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>