Re: [PATCH 1/2] media: i2c: max96714: add HAS_EVENTS subdev flag
From: Sakari Ailus
Date: Thu Sep 12 2024 - 08:15:25 EST
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