Add CameraManager.read_event() so that the user does not need to call os.read(). We use eventfd, and we must always read 8 bytes. Hiding that inside read_event() makes sense. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>