From: Ricardo Ribalda Date: Mon, 24 Feb 2025 10:34:53 +0000 (+0000) Subject: media: uvcvideo: Return the number of processed controls X-Git-Tag: v6.16-rc1~145^2~12 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ba4fafb02ad6a4eb2e00f861893b5db42ba54369;p=thirdparty%2Flinux.git media: uvcvideo: Return the number of processed controls If we let know our callers that we have not done anything, they will be able to optimize their decisions. Cc: stable@kernel.org Fixes: b4012002f3a3 ("[media] uvcvideo: Add support for control events") Reviewed-by: Laurent Pinchart Signed-off-by: Ricardo Ribalda Message-ID: <20250224-uvc-data-backup-v2-1-de993ed9823b@chromium.org> Signed-off-by: Hans de Goede Signed-off-by: Hans Verkuil --- diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c index e2052130f4c91..0c4d84eab42a3 100644 --- a/drivers/media/usb/uvc/uvc_ctrl.c +++ b/drivers/media/usb/uvc/uvc_ctrl.c @@ -2101,12 +2101,17 @@ int uvc_ctrl_begin(struct uvc_video_chain *chain) return mutex_lock_interruptible(&chain->ctrl_mutex) ? -ERESTARTSYS : 0; } +/* + * Returns the number of uvc controls that have been correctly set, or a + * negative number if there has been an error. + */ static int uvc_ctrl_commit_entity(struct uvc_device *dev, struct uvc_fh *handle, struct uvc_entity *entity, int rollback, struct uvc_control **err_ctrl) { + unsigned int processed_ctrls = 0; struct uvc_control *ctrl; unsigned int i; int ret; @@ -2141,6 +2146,9 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev, else ret = 0; + if (!ret) + processed_ctrls++; + if (rollback || ret < 0) memcpy(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT), uvc_ctrl_data(ctrl, UVC_CTRL_DATA_BACKUP), @@ -2159,7 +2167,7 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev, } } - return 0; + return processed_ctrls; } static int uvc_ctrl_find_ctrl_idx(struct uvc_entity *entity, @@ -2206,6 +2214,7 @@ int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback, if (!rollback) uvc_ctrl_send_events(handle, ctrls->controls, ctrls->count); + ret = 0; done: mutex_unlock(&chain->ctrl_mutex); return ret;