Hi Laurent, Sakari, Sorry for the delay. Back on this topic. On Mon, Oct 21, 2024 at 10:30:34AM +0300, Laurent Pinchart wrote: > On Mon, Oct 21, 2024 at 08:35:53AM +0200, Tommaso Merciai wrote: > > Hi Laurent, > > Thanks for your review. > > > > On Sun, Oct 20, 2024 at 07:43:54PM +0300, Laurent Pinchart wrote: > > > Hi Tommaso, > > > > > > Thank you for the patch. > > > > > > On Sun, Oct 20, 2024 at 06:35:32PM +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. > > > > If a control handler is set for the subdev then set the HAS_EVENTS > > > > flag automatically into v4l2_subdev_init_finalize() and use > > > > v4l2_ctrl_subdev_subscribe_event() and v4l2_event_subdev_unsubscribe() > > > > as default if subdev don't have .(un)subscribe control operations. > > > > > > I would add here > > > > > > This simplifies subdev drivers by avoiding the need to set the > > > V4L2_SUBDEV_FL_HAS_EVENTS flag and plug the event handlers, and ensures > > > consistency of the API exposed to userspace. > > > > > > And you can also add > > > > > > Suggested-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > > > > > > > Signed-off-by: Tommaso Merciai <tomm.merciai@xxxxxxxxx> > > > > > > Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > > > > Oks, Thanks again. > > > > > Now, can we simplify sensor drivers to drop the event handlers and the > > > flag ? :-) > > > > Yep, plan is add all to support v4l2_subdev_init_finalize() > > Removing: > > > > .subscribe_event = v4l2_ctrl_subdev_subscribe_event, > > .unsubscribe_event = v4l2_event_subdev_unsubscribe, > > > > if are used. And ofc V4L2_SUBDEV_FL_HAS_EVENTS. > > What I meant is looking at the I2C sensor drivers that currently > > - call v4l2_subdev_init_finalize() > - set V4L2_SUBDEV_FL_HAS_EVENTS > - set the .subscribe_event() and .unsubscribe_event() handlers > > and dropping the flag and handlers from them. Is that what you plan to > work on ? It's ok for you per/driver patch or you prefer a big single patch? Meanwhile I've prepared something here: https://gitlab.freedesktop.org/linux-media/users/tmerciai/-/compare/next...v6.12.0-rc1-nxp?from_project_id=22111 Let me know if you prefer (un)squashed version. Thanks in advance. :) Thanks & Regards, Tommaso > > > Meanwhile I think I will send v3 with your > > suggestions. :) > > > > > > --- > > > > Changes since v1: > > > > - Aligned event subscription with unsubscription as suggested by LPinchart, > > > > SAilus > > > > > > > > drivers/media/v4l2-core/v4l2-subdev.c | 22 ++++++++++++++++++++-- > > > > 1 file changed, 20 insertions(+), 2 deletions(-) > > > > > > > > diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c > > > > index 3a4ba08810d2..fad8fa1f63e8 100644 > > > > --- a/drivers/media/v4l2-core/v4l2-subdev.c > > > > +++ b/drivers/media/v4l2-core/v4l2-subdev.c > > > > @@ -691,10 +691,25 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg, > > > > return v4l2_event_dequeue(vfh, arg, file->f_flags & O_NONBLOCK); > > > > > > > > case VIDIOC_SUBSCRIBE_EVENT: > > > > - return v4l2_subdev_call(sd, core, subscribe_event, vfh, arg); > > > > + if (v4l2_subdev_has_op(sd, core, subscribe_event)) > > > > + return v4l2_subdev_call(sd, core, subscribe_event, > > > > + vfh, arg); > > > > + > > > > + if ((sd->flags & V4L2_SUBDEV_FL_HAS_EVENTS) && > > > > + vfh->ctrl_handler) > > > > + return v4l2_ctrl_subdev_subscribe_event(sd, vfh, arg); > > > > + > > > > + return -ENOIOCTLCMD; > > > > > > > > case VIDIOC_UNSUBSCRIBE_EVENT: > > > > - return v4l2_subdev_call(sd, core, unsubscribe_event, vfh, arg); > > > > + if (v4l2_subdev_has_op(sd, core, unsubscribe_event)) > > > > + return v4l2_subdev_call(sd, core, unsubscribe_event, > > > > + vfh, arg); > > > > + > > > > + if (sd->flags & V4L2_SUBDEV_FL_HAS_EVENTS) > > > > + return v4l2_event_subdev_unsubscribe(sd, vfh, arg); > > > > + > > > > + return -ENOIOCTLCMD; > > > > > > > > #ifdef CONFIG_VIDEO_ADV_DEBUG > > > > case VIDIOC_DBG_G_REGISTER: > > > > @@ -1641,6 +1656,9 @@ int __v4l2_subdev_init_finalize(struct v4l2_subdev *sd, const char *name, > > > > } > > > > } > > > > > > > > + if (sd->ctrl_handler) > > > > + sd->flags |= V4L2_SUBDEV_FL_HAS_EVENTS; > > > > + > > > > state = __v4l2_subdev_state_alloc(sd, name, key); > > > > if (IS_ERR(state)) > > > > return PTR_ERR(state); > > -- > Regards, > > Laurent Pinchart