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,
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
>>
>
>
