The V4L2ControlInfo class only stores a ControlRange. Make it inherit from ControlRange to provide a convenience constructor from a struct v4l2_query_ext_ctrl and rename it to V4L2ControlRange. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>