__uvc_query_v4l2_class
idx = __uvc_query_v4l2_class(chain, req_id, found_id);
if (__uvc_query_v4l2_class(chain, v4l2_id, 0) >= 0)
if (__uvc_query_v4l2_class(handle->chain, sev->id, 0) >= 0) {
if (__uvc_query_v4l2_class(handle->chain, sev->id, 0) >= 0)
if (__uvc_query_v4l2_class(chain, xctrl->id, 0) >= 0)
if (__uvc_query_v4l2_class(chain, xctrl->id, 0) >= 0)