Re: [PATCH 1/2] media: i2c: max96714: add HAS_EVENTS subdev flag

From: Tommaso Merciai
Date: Thu Sep 12 2024 - 07:11:28 EST


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?

Thanks & Regards,
Tommaso

>
> > Signed-off-by: Tommaso Merciai <tomm.merciai@xxxxxxxxx>
> > ---
> > drivers/media/i2c/max96714.c | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/media/i2c/max96714.c b/drivers/media/i2c/max96714.c
> > index 159753b13777..94b1bc000e48 100644
> > --- a/drivers/media/i2c/max96714.c
> > +++ b/drivers/media/i2c/max96714.c
> > @@ -602,7 +602,8 @@ static int max96714_create_subdev(struct max96714_priv *priv)
> > goto err_free_ctrl;
> > }
> >
> > - priv->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_STREAMS;
> > + priv->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> > + V4L2_SUBDEV_FL_HAS_EVENTS | V4L2_SUBDEV_FL_STREAMS;
> > priv->sd.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
> > priv->sd.entity.ops = &max96714_entity_ops;
> >
>
> --
> Regards,
>
> Laurent Pinchart