Hello Hans
On Fri, Mar 26, 2021 at 11:01 AM Ricardo Ribalda <ribalda@xxxxxxxxxxxx> wrote:
>
> From: Hans Verkuil <hverkuil@xxxxxxxxx>
>
> Check for inactive controls in uvc_ctrl_is_accessible().
> Use the new value for the master_id controls if present,
> otherwise use the existing value to determine if it is OK
> to set the control. Doing this here avoids attempting to
> set an inactive control, which will return an error from the
> USB device.
>
> Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
> ---
> drivers/media/usb/uvc/uvc_ctrl.c | 28 +++++++++++++++++++++++++++-
> drivers/media/usb/uvc/uvc_v4l2.c | 4 ++--
> drivers/media/usb/uvc/uvcvideo.h | 3 ++-
> 3 files changed, 31 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
> index d9d4add1e813..6e7b904bc33d 100644
> --- a/drivers/media/usb/uvc/uvc_ctrl.c
> +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> @@ -1047,10 +1047,18 @@ static int uvc_query_v4l2_class(struct uvc_video_chain *chain, u32 req_id,
> }
>
> int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id,
> - bool read)
> + const struct v4l2_ext_controls *ctrls,
> + unsigned long ioctl)
> {
> + struct uvc_control_mapping *master_map = NULL;
> + struct uvc_control *master_ctrl = NULL;
> struct uvc_control_mapping *mapping;
> struct uvc_control *ctrl;
> + bool read = ioctl == VIDIOC_G_EXT_CTRLS;
> + bool try = ioctl == VIDIOC_TRY_EXT_CTRLS;
> + s32 val;
> + int ret;
> + int i;
>
> if (__uvc_query_v4l2_class(chain, v4l2_id, 0) >= 0)
> return -EACCES;
> @@ -1065,6 +1073,24 @@ int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id,
> if (!(ctrl->info.flags & UVC_CTRL_FLAG_SET_CUR) && !read)
> return -EACCES;
>
> + if (read || try || !mapping->master_id)
> + return 0;
> +
> + for (i = ctrls->count - 1; i >= 0; i--)
> + if (ctrls->controls[i].id == mapping->master_id)
> + return ctrls->controls[i].value ==
> + mapping->master_manual ? 0 : -EACCES;
> +
> + __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 0;
> +
> + ret = __uvc_ctrl_get(chain, master_ctrl, master_map, &val);
> + if (ret >= 0 && val != mapping->master_manual)
> + return -EACCES;
Maybe we could use uvc_ctrl_is_inactive().
Please checkout:
https://git.kernel.org/pub/scm/linux/kernel/git/ribalda/linux.git/commit/?h=uvc-compliance-v10&id=f49f7c84ece18df72094a18011f2fbeb20dc1b15
and if you like it better that will be what I resend for v10 ;)
Thanks!
> +
> return 0;
> }
>
> diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
> index 8d8b12a4db34..0f4d893eff46 100644
> --- a/drivers/media/usb/uvc/uvc_v4l2.c
> +++ b/drivers/media/usb/uvc/uvc_v4l2.c
> @@ -1000,8 +1000,8 @@ static int uvc_ctrl_check_access(struct uvc_video_chain *chain,
> int ret = 0;
>
> for (i = 0; i < ctrls->count; ++ctrl, ++i) {
> - ret = uvc_ctrl_is_accessible(chain, ctrl->id,
> - ioctl == VIDIOC_G_EXT_CTRLS);
> + ret = uvc_ctrl_is_accessible(chain, ctrl->id, ctrls,
> + ioctl);
> if (ret)
> break;
> }
> diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
> index 0313b30f0cea..20bc681315fb 100644
> --- a/drivers/media/usb/uvc/uvcvideo.h
> +++ b/drivers/media/usb/uvc/uvcvideo.h
> @@ -901,7 +901,8 @@ static inline int uvc_ctrl_rollback(struct uvc_fh *handle)
> int uvc_ctrl_get(struct uvc_video_chain *chain, struct v4l2_ext_control *xctrl);
> int uvc_ctrl_set(struct uvc_fh *handle, struct v4l2_ext_control *xctrl);
> int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id,
> - bool read);
> + const struct v4l2_ext_controls *ctrls,
> + unsigned long ioctl);
>
> int uvc_xu_ctrl_query(struct uvc_video_chain *chain,
> struct uvc_xu_control_query *xqry);
> --
> 2.31.0.291.g576ba9dcdaf-goog
>
--
Ricardo Ribalda
