Re: [PATCH 09/10] uvcvideo: Properly report the inactive flag for inactive controls

Laurent Pinchart
2012-03-28T09:12:38Z

Hi Hans,

Thanks for the patch.

On Sunday 25 March 2012 13:56:49 Hans de Goede wrote:
> Note the unused in this patch slave_ids addition to the mappings will get
> used in a follow up patch to generate control change events for the slave
> ctrls when their flags change due to the master control changing value.
>
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
> drivers/media/video/uvc/uvc_ctrl.c | 33 +++++++++++++++++++++++++++++++++
> drivers/media/video/uvc/uvcvideo.h | 4 ++++
> 2 files changed, 37 insertions(+)
>
> diff --git a/drivers/media/video/uvc/uvc_ctrl.c
> b/drivers/media/video/uvc/uvc_ctrl.c index 742496f..91d9007 100644
> --- a/drivers/media/video/uvc/uvc_ctrl.c
> +++ b/drivers/media/video/uvc/uvc_ctrl.c

[snip]

> @@ -943,6 +961,8 @@ static int __uvc_query_v4l2_ctrl(struct uvc_video_chain
> *chain, struct uvc_control_mapping *mapping,
> struct v4l2_queryctrl *v4l2_ctrl)
> {
> + struct uvc_control_mapping *master_map;
> + struct uvc_control *master_ctrl = NULL;
> struct uvc_menu_info *menu;
> unsigned int i;
> int ret = 0;
> @@ -958,6 +978,19 @@ 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)
> + master_ctrl = uvc_find_control(chain, mapping->master_id,
> + &master_map);

As an optimization, do you think it would make sense to add a struct
uvc_contro *master_ctrl field to struct uvc_control_mapping, and fill it in
uvc_ctrl_init_ctrl() ? That would require a loop over the mappings at
initialization time, but would get rid of the search operation at runtime. The
master_ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR check would be performed at
initialization time as well, and master_ctrl would be left NULL it the master
control doesn't support the GET_CUR query.

> + if (master_ctrl && (master_ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR)) {
> + s32 val;
> + ret = __uvc_ctrl_get(chain, master_ctrl, master_map, &val);
> + if (ret < 0)
> + goto done;
> +
> + if (val != mapping->master_manual)
> + v4l2_ctrl->flags |= V4L2_CTRL_FLAG_INACTIVE;
> + }
> +
> if (!ctrl->cached) {
> ret = uvc_ctrl_populate_cache(chain, ctrl);
> if (ret < 0)

--
Regards,

Laurent Pinchart