The MediaDevice lock is meant to prevent concurrent usage of multiple cameras from the same pipeline handlers. As media devices are acquired by pipeline handlers, we can't have multiple pipeline handlers trying to lock the same media device. The recursive locking detection can thus be moved to the pipeline handler. This simplifies the media device implementation that now implements true lock semantics, and prepares for support of concurrent camera usage. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Umang Jain <umang.jain@ideasonboard.com>