Re: [PATCH v10 21/21] media: uvcvideo: Return -EACCES to inactive controls

From: Ricardo Ribalda
Date: Wed Jul 07 2021 - 05:08:08 EST


Hi Hans

On Tue, 6 Jul 2021 at 16:19, Hans Verkuil <hverkuil-cisco@xxxxxxxxx> wrote:
>
> On 30/06/2021 14:51, Ricardo Ribalda wrote:
> > Hi Hans
> >
> >
> > On Wed, 30 Jun 2021 at 11:03, Hans Verkuil <hverkuil-cisco@xxxxxxxxx> wrote:
> >>
> >> Hi Ricardo,
> >>
> >> On 25/06/2021 15:55, Ricardo Ribalda wrote:
> >>> Hi Hans
> >>>
> >>> On Fri, 25 Jun 2021 at 13:07, Hans Verkuil <hverkuil-cisco@xxxxxxxxx> wrote:
> >>>>
> >>>> On 25/06/2021 12:29, Ricardo Ribalda wrote:
> >>>>> Hi Hans
> >>>>>
> >>>>> Did you have some hardware that did not work fine without this patch?
> >>>>> Am I remembering correctly?
> >>>>
> >>>> Yes, that's correct. It's one of my webcams, but I can't remember which one
> >>>> it is. You probably want me to test this v10?
> >>>>
> >>>> Regards,
> >>>
> >>> That would be awesome. Thanks!
> >>
> >> You can add my:
> >>
> >> Tested-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
> >
> > Thanks a lot for testing it!
> >
> > Sorry to bother you, but could I ask you to try again, but with this
> > patch reverted? This is v10 1-20, without 21/21
>
> I tried with and without this patch and I didn't see any difference. Unfortunately,
> I don't remember the exact details of what I tested last time and with which hardware.
>
> I would drop this patch, it can always be added later.

Thank you very much for testing. I think there were no more comments
in this set.

Laurent: Shall I resend the series without this last patch, or can you
take it as is ignoring the last one?

Thanks!

>
> Regards,
>
> Hans
>
> >
> >
> > Thanks!
> >>
> >> to this series.
> >>
> >> I do get these warnings (depends on the webcam model, though, some do, some don't):
> >>
> >> Streaming ioctls:
> >> test read/write: OK (Not Supported)
> >> test blocking wait: OK
> >> warn: v4l2-test-buffers.cpp(438): got sequence number 1, expected 0
> >> test MMAP (no poll): OK
> >> warn: v4l2-test-buffers.cpp(438): got sequence number 1, expected 0
> >> test MMAP (select): OK
> >> warn: v4l2-test-buffers.cpp(438): got sequence number 1, expected 0
> >> test MMAP (epoll): OK
> >> warn: v4l2-test-buffers.cpp(438): got sequence number 1, expected 0
> >> test USERPTR (no poll): OK
> >> warn: v4l2-test-buffers.cpp(438): got sequence number 1, expected 0
> >> test USERPTR (select): OK
> >> test DMABUF: Cannot test, specify --expbuf-device
> >>
> >> It's something to do with the Field ID, but I'm not sure if this is really correctly
> >> reporting a dropped frame, or if it is a false report and the sequence counter was
> >> wrongly incremented.
> >>
> >> This is a separate issue, though, and doesn't block this series.
> >>
> >> Regards,
> >>
> >> Hans
> >>
> >>>
> >>>>
> >>>> Hans
> >>>>
> >>>>>
> >>>>> Thanks!
> >>>>>
> >>>>> On Fri, 18 Jun 2021 at 14:29, Ricardo Ribalda <ribalda@xxxxxxxxxxxx> wrote:
> >>>>>>
> >>>>>> If a control is inactive return -EACCES to let the userspace know that
> >>>>>> the value will not be applied automatically when the control is active
> >>>>>> again.
> >>>>>>
> >>>>>> Also make sure that query_v4l2_ctrl doesn't return an error.
> >>>>>>
> >>>>>> Suggested-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
> >>>>>> Reviewed-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
> >>>>>> Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
> >>>>>> ---
> >>>>>> drivers/media/usb/uvc/uvc_ctrl.c | 73 +++++++++++++++++++++-----------
> >>>>>> 1 file changed, 49 insertions(+), 24 deletions(-)
> >>>>>>
> >>>>>> diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
> >>>>>> index da44d5c0b9ad..4f80c06d3c43 100644
> >>>>>> --- a/drivers/media/usb/uvc/uvc_ctrl.c
> >>>>>> +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> >>>>>> @@ -1104,13 +1104,36 @@ static const char *uvc_map_get_name(const struct uvc_control_mapping *map)
> >>>>>> return "Unknown Control";
> >>>>>> }
> >>>>>>
> >>>>>> +static bool uvc_ctrl_is_inactive(struct uvc_video_chain *chain,
> >>>>>> + struct uvc_control *ctrl,
> >>>>>> + struct uvc_control_mapping *mapping)
> >>>>>> +{
> >>>>>> + struct uvc_control_mapping *master_map = NULL;
> >>>>>> + struct uvc_control *master_ctrl = NULL;
> >>>>>> + s32 val;
> >>>>>> + int ret;
> >>>>>> +
> >>>>>> + if (!mapping->master_id)
> >>>>>> + return false;
> >>>>>> +
> >>>>>> + __uvc_find_control(ctrl->entity, mapping->master_id, &master_map,
> >>>>>> + &master_ctrl, 0);
> >>>>>> +
> >>>>>> + if (!master_ctrl || !(master_ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR))
> >>>>>> + return false;
> >>>>>> +
> >>>>>> + ret = __uvc_ctrl_get(chain, master_ctrl, master_map, &val);
> >>>>>> + if (ret < 0 || val == mapping->master_manual)
> >>>>>> + return false;
> >>>>>> +
> >>>>>> + return true;
> >>>>>> +}
> >>>>>> +
> >>>>>> static int __uvc_query_v4l2_ctrl(struct uvc_video_chain *chain,
> >>>>>> struct uvc_control *ctrl,
> >>>>>> struct uvc_control_mapping *mapping,
> >>>>>> struct v4l2_queryctrl *v4l2_ctrl)
> >>>>>> {
> >>>>>> - struct uvc_control_mapping *master_map = NULL;
> >>>>>> - struct uvc_control *master_ctrl = NULL;
> >>>>>> const struct uvc_menu_info *menu;
> >>>>>> unsigned int i;
> >>>>>>
> >>>>>> @@ -1126,18 +1149,8 @@ static int __uvc_query_v4l2_ctrl(struct uvc_video_chain *chain,
> >>>>>> if (!(ctrl->info.flags & UVC_CTRL_FLAG_SET_CUR))
> >>>>>> v4l2_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> >>>>>>
> >>>>>> - if (mapping->master_id)
> >>>>>> - __uvc_find_control(ctrl->entity, mapping->master_id,
> >>>>>> - &master_map, &master_ctrl, 0);
> >>>>>> - if (master_ctrl && (master_ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR)) {
> >>>>>> - s32 val;
> >>>>>> - int ret = __uvc_ctrl_get(chain, master_ctrl, master_map, &val);
> >>>>>> - if (ret < 0)
> >>>>>> - return ret;
> >>>>>> -
> >>>>>> - if (val != mapping->master_manual)
> >>>>>> - v4l2_ctrl->flags |= V4L2_CTRL_FLAG_INACTIVE;
> >>>>>> - }
> >>>>>> + if (uvc_ctrl_is_inactive(chain, ctrl, mapping))
> >>>>>> + v4l2_ctrl->flags |= V4L2_CTRL_FLAG_INACTIVE;
> >>>>>>
> >>>>>> if (!ctrl->cached) {
> >>>>>> int ret = uvc_ctrl_populate_cache(chain, ctrl);
> >>>>>> @@ -1660,25 +1673,37 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev,
> >>>>>> return 0;
> >>>>>> }
> >>>>>>
> >>>>>> -static int uvc_ctrl_find_ctrl_idx(struct uvc_entity *entity,
> >>>>>> - struct v4l2_ext_controls *ctrls,
> >>>>>> - struct uvc_control *uvc_control)
> >>>>>> +static int uvc_ctrl_commit_error(struct uvc_video_chain *chain,
> >>>>>> + struct uvc_entity *entity,
> >>>>>> + struct v4l2_ext_controls *ctrls,
> >>>>>> + struct uvc_control *err_control,
> >>>>>> + int ret)
> >>>>>> {
> >>>>>> struct uvc_control_mapping *mapping;
> >>>>>> struct uvc_control *ctrl_found;
> >>>>>> unsigned int i;
> >>>>>>
> >>>>>> - if (!entity)
> >>>>>> - return ctrls->count;
> >>>>>> + if (!entity) {
> >>>>>> + ctrls->error_idx = ctrls->count;
> >>>>>> + return ret;
> >>>>>> + }
> >>>>>>
> >>>>>> for (i = 0; i < ctrls->count; i++) {
> >>>>>> __uvc_find_control(entity, ctrls->controls[i].id, &mapping,
> >>>>>> &ctrl_found, 0);
> >>>>>> - if (uvc_control == ctrl_found)
> >>>>>> - return i;
> >>>>>> + if (err_control == ctrl_found)
> >>>>>> + break;
> >>>>>> }
> >>>>>> + ctrls->error_idx = i;
> >>>>>> +
> >>>>>> + /* We could not find the control that failed. */
> >>>>>> + if (i == ctrls->count)
> >>>>>> + return ret;
> >>>>>> +
> >>>>>> + if (uvc_ctrl_is_inactive(chain, err_control, mapping))
> >>>>>> + return -EACCES;
> >>>>>>
> >>>>>> - return ctrls->count;
> >>>>>> + return ret;
> >>>>>> }
> >>>>>>
> >>>>>> int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,
> >>>>>> @@ -1701,8 +1726,8 @@ int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,
> >>>>>> uvc_ctrl_send_events(handle, ctrls->controls, ctrls->count);
> >>>>>> done:
> >>>>>> if (ret < 0 && ctrls)
> >>>>>> - ctrls->error_idx = uvc_ctrl_find_ctrl_idx(entity, ctrls,
> >>>>>> - err_ctrl);
> >>>>>> + ret = uvc_ctrl_commit_error(chain, entity, ctrls, err_ctrl,
> >>>>>> + ret);
> >>>>>> mutex_unlock(&chain->ctrl_mutex);
> >>>>>> return ret;
> >>>>>> }
> >>>>>> --
> >>>>>> 2.32.0.288.g62a8d224e6-goog
> >>>>>>
> >>>>>
> >>>>>
> >>>>
> >>>
> >>>
> >>
> >
> >
>


--
Ricardo Ribalda