Volatile controls can change their value outside the v4l-ctrl framework. We should ignore the cached written value of the ctrl when evaluating if we should run s_ctrl. Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@xxxxxxxxx> --- v4: Hans Verkuil: explicity set has_changed to false. and add comment drivers/media/v4l2-core/v4l2-ctrls.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c index 45c5b47..f34a689 100644 --- a/drivers/media/v4l2-core/v4l2-ctrls.c +++ b/drivers/media/v4l2-core/v4l2-ctrls.c @@ -1609,6 +1609,17 @@ static int cluster_changed(struct v4l2_ctrl *master) if (ctrl == NULL) continue; + + if (ctrl->flags & V4L2_CTRL_FLAG_VOLATILE) { + /* + * Set has_changed to false to avoid generating + * the event V4L2_EVENT_CTRL_CH_VALUE + */ + ctrl->has_changed = false; + changed = true; + continue; + } + for (idx = 0; !ctrl_changed && idx < ctrl->elems; idx++) ctrl_changed = !ctrl->type_ops->equal(ctrl, idx, ctrl->p_cur, ctrl->p_new); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html