@@ -1825,11 +1825,14 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev,
unsigned int processed_ctrls = 0;
struct uvc_control *ctrl;
unsigned int i;
- int ret;
+ int ret = 0;
if (entity == NULL)
return 0;
+ if (err_ctrl)
+ *err_ctrl = NULL;
+
for (i = 0; i < entity->ncontrols; ++i) {
ctrl = &entity->controls[i];
if (!ctrl->initialized)
@@ -1854,8 +1857,6 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev,
dev->intfnum, ctrl->info.selector,
uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
ctrl->info.size);
- else
- ret = 0;
if (!ret)
processed_ctrls++;
@@ -1868,12 +1869,19 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev,
ctrl->dirty = 0;
if (ret < 0) {
- if (err_ctrl)
+ if (err_ctrl && !*err_ctrl)
*err_ctrl = ctrl;
- return ret;
+ /*
+ * If we fail to set a control, we need to rollback
+ * the next ones.
+ */
+ rollback = 1;
}
}
+ if (ret)
+ return ret;
+
return processed_ctrls;
}
@@ -1904,6 +1912,7 @@ int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,
struct uvc_video_chain *chain = handle->chain;
struct uvc_control *err_ctrl;
struct uvc_entity *entity;
+ int ret_out = 0;
int ret = 0;
/* Find the control. */
@@ -1915,16 +1924,23 @@ int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,
ctrls->error_idx =
uvc_ctrl_find_ctrl_idx(entity, ctrls,
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) {
uvc_ctrl_send_events(handle, entity,
ctrls->controls, ctrls->count);
}
}
-done:
mutex_unlock(&chain->ctrl_mutex);
- return ret < 0 ? ret : 0;
+ return ret_out;
}
int uvc_ctrl_get(struct uvc_video_chain *chain,
If we wail 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: b4012002f3a3 ("[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> --- drivers/media/usb/uvc/uvc_ctrl.c | 32 ++++++++++++++++++++++++-------- 1 file changed, 24 insertions(+), 8 deletions(-)