Hi Laurent, On Thu, Sep 12, 2024 at 03:05:10PM +0300, Laurent Pinchart wrote: > On Thu, Sep 12, 2024 at 01:11:13PM +0200, Tommaso Merciai wrote: > > Hi Laurent, > > > > On Thu, Sep 12, 2024 at 01:44:09PM +0300, Laurent Pinchart wrote: > > > Hi Tommaso, > > > > > > On Tue, Sep 10, 2024 at 03:44:27PM +0200, Tommaso Merciai wrote: > > > > Controls can be exposed to userspace via a v4l-subdevX device, and > > > > userspace has to be able to subscribe to control events so that it is > > > > notified when the control changes value. Add missing HAS_EVENTS flag. > > > > > > How is this supposed to work, given that the driver doesn't implement > > > .subscribe_event() ? > > > > You are completely right, sorry. > > I think in both cases I'm missing: > > > > diff --git a/drivers/media/i2c/max96714.c b/drivers/media/i2c/max96714.c > > index 94b1bc000e48..2257b6b807ea 100644 > > --- a/drivers/media/i2c/max96714.c > > +++ b/drivers/media/i2c/max96714.c > > @@ -17,6 +17,7 @@ > > > > #include <media/v4l2-cci.h> > > #include <media/v4l2-ctrls.h> > > +#include <media/v4l2-event.h> > > #include <media/v4l2-fwnode.h> > > #include <media/v4l2-subdev.h> > > > > @@ -488,6 +489,8 @@ static int max96714_log_status(struct v4l2_subdev *sd) > > > > static const struct v4l2_subdev_core_ops max96714_subdev_core_ops = { > > .log_status = max96714_log_status, > > + .subscribe_event = v4l2_ctrl_subdev_subscribe_event, > > + .unsubscribe_event = v4l2_event_subdev_unsubscribe, > > }; > > > > static const struct v4l2_subdev_video_ops max96714_video_ops = { > > > > Like you suggest. Or I'm wrong? > > That looks better :-) > > Out of curiosity, what's your use case for control events ? I'm not sure if there's a use case, however control event should be supported when a driver supports controls. -- Regards, Sakari Ailus