media: uvcvideo: Rollback non processed entities on error

commit a70705d3c020d0d5c3ab6a5cc93e011ac35e7d48 upstream.

If we fail to commit an entity, we need to restore the
UVC_CTRL_DATA_BACKUP for the other uncommitted entities. Otherwise the
control cache and the device would be out of sync.

Cc: stable@kernel.org
Fixes: b4012002f3 ("[media] uvcvideo: Add support for control events")
Reported-by: Hans de Goede <hdegoede@redhat.com>
Closes: https://lore.kernel.org/linux-media/fe845e04-9fde-46ee-9763-a6f00867929a@redhat.com/
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Message-ID: <20250224-uvc-data-backup-v2-3-de993ed9823b@chromium.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ricardo Ribalda
2025-02-24 10:34:55 +00:00
committed by Greg Kroah-Hartman
parent f165d04c41
commit 56aa7679c9

View File

@@ -1801,7 +1801,7 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev,
unsigned int processed_ctrls = 0; unsigned int processed_ctrls = 0;
struct uvc_control *ctrl; struct uvc_control *ctrl;
unsigned int i; unsigned int i;
int ret; int ret = 0;
if (entity == NULL) if (entity == NULL)
return 0; return 0;
@@ -1830,8 +1830,6 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev,
dev->intfnum, ctrl->info.selector, dev->intfnum, ctrl->info.selector,
uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT), uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
ctrl->info.size); ctrl->info.size);
else
ret = 0;
if (!ret) if (!ret)
processed_ctrls++; processed_ctrls++;
@@ -1843,17 +1841,25 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev,
ctrl->dirty = 0; ctrl->dirty = 0;
if (ret < 0) {
if (err_ctrl)
*err_ctrl = ctrl;
return ret;
}
if (!rollback && handle && if (!rollback && handle &&
ctrl->info.flags & UVC_CTRL_FLAG_ASYNCHRONOUS) ctrl->info.flags & UVC_CTRL_FLAG_ASYNCHRONOUS)
uvc_ctrl_set_handle(handle, ctrl, handle); uvc_ctrl_set_handle(handle, ctrl, handle);
if (ret < 0 && !rollback) {
if (err_ctrl)
*err_ctrl = ctrl;
/*
* If we fail to set a control, we need to rollback
* the next ones.
*/
rollback = 1;
} }
}
if (ret)
return ret;
return processed_ctrls; return processed_ctrls;
} }
@@ -1884,7 +1890,8 @@ int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,
struct uvc_video_chain *chain = handle->chain; struct uvc_video_chain *chain = handle->chain;
struct uvc_control *err_ctrl; struct uvc_control *err_ctrl;
struct uvc_entity *entity; struct uvc_entity *entity;
int ret = 0; int ret_out = 0;
int ret;
/* Find the control. */ /* Find the control. */
list_for_each_entry(entity, &chain->entities, chain) { list_for_each_entry(entity, &chain->entities, chain) {
@@ -1895,17 +1902,23 @@ int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,
ctrls->error_idx = ctrls->error_idx =
uvc_ctrl_find_ctrl_idx(entity, ctrls, uvc_ctrl_find_ctrl_idx(entity, ctrls,
err_ctrl); err_ctrl);
goto done; /*
* When we fail to commit an entity, we need to
* restore the UVC_CTRL_DATA_BACKUP for all the
* controls in the other entities, otherwise our cache
* and the hardware will be out of sync.
*/
rollback = 1;
ret_out = ret;
} else if (ret > 0 && !rollback) { } else if (ret > 0 && !rollback) {
uvc_ctrl_send_events(handle, entity, uvc_ctrl_send_events(handle, entity,
ctrls->controls, ctrls->count); ctrls->controls, ctrls->count);
} }
} }
ret = 0;
done:
mutex_unlock(&chain->ctrl_mutex); mutex_unlock(&chain->ctrl_mutex);
return ret; return ret_out;
} }
int uvc_ctrl_get(struct uvc_video_chain *chain, int uvc_ctrl_get(struct uvc_video_chain *chain,