Re: [PATCH v14 08/11] media: uvcvideo: support V4L2_CTRL_WHICH_MIN/MAX_VAL

Laurent Pinchart
2023-12-08T15:26:15Z

Hi Yunke,

Thank you for the patch.

On Fri, Dec 01, 2023 at 04:18:59PM +0900, Yunke Cao wrote:
> Add support for V4L2_CTRL_WHICH_MIN/MAX_VAL in uvc driver.
> It is useful for the V4L2_CID_UVC_REGION_OF_INTEREST_RECT control.
>
> Reviewed-by: Ricardo Ribalda <ribalda@chromium.org>
> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
> Signed-off-by: Yunke Cao <yunkec@google.com>
> ---
> Changelog since v11:
> - No change.
> Changelog since v10:
> - Added Reviewed-by from Sergey.
> Changelog since v9:
> - Revert a change in v7 that causes v4l2-compliance failure:
> - In uvc_ioctl_g_ext_ctrls(), when v4l2_which is not V4L2_CTRL_WHICH_*_VAL,
> - treat it the same as cur instead of returning EINVAL. This is the existing
> - behavior.
> - The change in v7 of returning EINVAL fails the check in
> - v4l2-compliance/v4l2-test-controls.cpp#L834.
> Changelog since v8:
> - No change.
> Changelog since v7:
> - Address some comments.
>
> drivers/media/usb/uvc/uvc_ctrl.c | 64 +++++++++++++++++++++++++++-----
> drivers/media/usb/uvc/uvc_v4l2.c | 7 +++-
> drivers/media/usb/uvc/uvcvideo.h | 3 +-
> 3 files changed, 61 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
> index aae2480496b7..c073c2a02102 100644
> --- a/drivers/media/usb/uvc/uvc_ctrl.c
> +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> @@ -1247,11 +1247,18 @@ int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id,
> if (!ctrl)
> return -EINVAL;
>
> - if (!(ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR) && read)
> - return -EACCES;
> -
> - if (!(ctrl->info.flags & UVC_CTRL_FLAG_SET_CUR) && !read)
> - return -EACCES;
> + if (read) {
> + if (ctrls->which == V4L2_CTRL_WHICH_MIN_VAL ||
> + ctrls->which == V4L2_CTRL_WHICH_MAX_VAL) {
> + if (!(ctrl->info.flags & UVC_CTRL_FLAG_GET_MIN) ||
> + !(ctrl->info.flags & UVC_CTRL_FLAG_GET_MAX))
> + return -EINVAL;

Shouldn't this be

if (ctrls->which == V4L2_CTRL_WHICH_MIN_VAL &&
!(ctrl->info.flags & UVC_CTRL_FLAG_GET_MIN))
return -EINVAL;

if (ctrls->which == V4L2_CTRL_WHICH_MAX_VAL &&
!(ctrl->info.flags & UVC_CTRL_FLAG_GET_MAX))
return -EINVAL;

> + } else if (!(ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR))
> + return -EACCES;

if (ctrls->which == V4L2_CTRL_WHICH_CUR_VAL &&
!(ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR))
return -EACCES;

> + } else {
> + if (!(ctrl->info.flags & UVC_CTRL_FLAG_SET_CUR))
> + return -EACCES;
> + }
>
> if (ioctl != VIDIOC_S_EXT_CTRLS || !mapping->master_id)
> return 0;
> @@ -1332,6 +1339,9 @@ static int __uvc_query_v4l2_ctrl(struct uvc_video_chain *chain,
> v4l2_ctrl->flags |= V4L2_CTRL_FLAG_WRITE_ONLY;
> if (!(ctrl->info.flags & UVC_CTRL_FLAG_SET_CUR))
> v4l2_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> + if ((ctrl->info.flags & UVC_CTRL_FLAG_GET_MAX) &&
> + (ctrl->info.flags & UVC_CTRL_FLAG_GET_MIN))
> + v4l2_ctrl->flags |= V4L2_CTRL_FLAG_HAS_WHICH_MIN_MAX;
>
> if (mapping->master_id)
> __uvc_find_control(ctrl->entity, mapping->master_id,
> @@ -1981,6 +1991,7 @@ int uvc_ctrl_get(struct uvc_video_chain *chain,
> static int __uvc_ctrl_get_boundary_std(struct uvc_video_chain *chain,
> struct uvc_control *ctrl,
> struct uvc_control_mapping *mapping,
> + u32 v4l2_which,
> struct v4l2_ext_control *xctrl)
> {
> struct v4l2_queryctrl qc = { .id = xctrl->id };
> @@ -1990,28 +2001,59 @@ static int __uvc_ctrl_get_boundary_std(struct uvc_video_chain *chain,
> if (ret < 0)
> return ret;
>
> - xctrl->value = qc.default_value;
> + switch (v4l2_which) {
> + case V4L2_CTRL_WHICH_DEF_VAL:
> + xctrl->value = qc.default_value;
> + break;
> + case V4L2_CTRL_WHICH_MIN_VAL:
> + xctrl->value = qc.minimum;
> + break;
> + case V4L2_CTRL_WHICH_MAX_VAL:
> + xctrl->value = qc.maximum;
> + break;
> + }
> +
> return 0;
> }
>
> static int __uvc_ctrl_get_boundary_compound(struct uvc_video_chain *chain,
> struct uvc_control *ctrl,
> struct uvc_control_mapping *mapping,
> + u32 v4l2_which,
> struct v4l2_ext_control *xctrl)
> {
> + u32 flag, id;
> int ret;
>
> + switch (v4l2_which) {
> + case V4L2_CTRL_WHICH_DEF_VAL:
> + flag = UVC_CTRL_FLAG_GET_DEF;
> + id = UVC_CTRL_DATA_DEF;
> + break;
> + case V4L2_CTRL_WHICH_MIN_VAL:
> + flag = UVC_CTRL_FLAG_GET_MIN;
> + id = UVC_CTRL_DATA_MIN;
> + break;
> + case V4L2_CTRL_WHICH_MAX_VAL:
> + flag = UVC_CTRL_FLAG_GET_MAX;
> + id = UVC_CTRL_DATA_MAX;
> + break;
> + }
> +
> + if (!(ctrl->info.flags & flag) && flag != UVC_CTRL_FLAG_GET_DEF)
> + return -EINVAL;
> +
> if (!ctrl->cached) {
> ret = uvc_ctrl_populate_cache(chain, ctrl);
> if (ret < 0)
> return ret;
> }
>
> - return __uvc_ctrl_get_compound(mapping, ctrl, UVC_CTRL_DATA_DEF, xctrl);
> + return __uvc_ctrl_get_compound(mapping, ctrl, id, xctrl);
> }
>
> int uvc_ctrl_get_boundary(struct uvc_video_chain *chain,
> - struct v4l2_ext_control *xctrl)
> + struct v4l2_ext_control *xctrl, u32 v4l2_which)
> {
> struct uvc_control *ctrl;
> struct uvc_control_mapping *mapping;
> @@ -2028,9 +2070,11 @@ int uvc_ctrl_get_boundary(struct uvc_video_chain *chain,
>
> if (uvc_ctrl_mapping_is_compound(mapping))
> ret = __uvc_ctrl_get_boundary_compound(chain, ctrl, mapping,
> - xctrl);
> + v4l2_which, xctrl);
> else
> - ret = __uvc_ctrl_get_boundary_std(chain, ctrl, mapping, xctrl);
> + ret = __uvc_ctrl_get_boundary_std(chain, ctrl, mapping,
> + v4l2_which, xctrl);
> +
>
> done:
> mutex_unlock(&chain->ctrl_mutex);
> diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
> index ff72caf7bc9e..352f62ef02f2 100644
> --- a/drivers/media/usb/uvc/uvc_v4l2.c
> +++ b/drivers/media/usb/uvc/uvc_v4l2.c
> @@ -1094,9 +1094,12 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file, void *fh,
> if (ret < 0)
> return ret;
>
> - if (ctrls->which == V4L2_CTRL_WHICH_DEF_VAL) {
> + switch (ctrls->which) {
> + case V4L2_CTRL_WHICH_DEF_VAL:
> + case V4L2_CTRL_WHICH_MIN_VAL:
> + case V4L2_CTRL_WHICH_MAX_VAL:
> for (i = 0; i < ctrls->count; ++ctrl, ++i) {
> - ret = uvc_ctrl_get_boundary(chain, ctrl);
> + ret = uvc_ctrl_get_boundary(chain, ctrl, ctrls->which);
> if (ret < 0) {
> ctrls->error_idx = i;
> return ret;
> diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
> index 11805b729c22..6fda40919e7f 100644
> --- a/drivers/media/usb/uvc/uvcvideo.h
> +++ b/drivers/media/usb/uvc/uvcvideo.h
> @@ -790,7 +790,8 @@ 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_get_boundary(struct uvc_video_chain *chain,
> - struct v4l2_ext_control *xctrl);
> + struct v4l2_ext_control *xctrl,
> + u32 v4l2_which);
> 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,
> const struct v4l2_ext_controls *ctrls,

--
Regards,

Laurent Pinchart