Hi Hans
On Mon, 2 Dec 2024 at 12:17, Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
>
> Hi All,
>
> While reviewing Ricardo's "[PATCH v4 0/4] media: uvcvideo: Two fixes for
> async controls" series I noticed that uvc_ctrl_commit() stops processing
> entities on an error:
>
> list_for_each_entry(entity, &chain->entities, chain) {
> ret = uvc_ctrl_commit_entity(chain->dev, entity, rollback,
> &err_ctrl);
> if (ret < 0) {
> if (ctrls)
> ctrls->error_idx =
> uvc_ctrl_find_ctrl_idx(entity, ctrls,
> err_ctrl);
> goto done;
> }
> }
>
> This means that if there are further entities with changed ctrls
> in the chain, not only do the new ctrl values not get committed
> which is expected. But the new values do get kept in the drivers
> cached ctrl values.
>
> I believe that what needs to happen instead is that the loop
> over all entities is continued, but for the other entities
> uvc_ctrl_commit_entity() needs to be called with rollback = 1
> after the error.
>
I believe that you are correct. Check out this patchset:
https://lore.kernel.org/linux-media/20241210-uvc-data-backup-v1-0-77141e439cc3@xxxxxxxxxxxx/T/#t
Regards!
> Regards,
>
> Hans
>
>
>
>
--
Ricardo Ribalda
