diff --git a/libc/kernel/uapi/linux/uvcvideo.h b/libc/kernel/uapi/linux/uvcvideo.h
index 7ae7aad..719147a 100644
--- a/libc/kernel/uapi/linux/uvcvideo.h
+++ b/libc/kernel/uapi/linux/uvcvideo.h
@@ -34,6 +34,7 @@
 #define UVC_CTRL_FLAG_GET_DEF (1 << 5)
 #define UVC_CTRL_FLAG_RESTORE (1 << 6)
 #define UVC_CTRL_FLAG_AUTO_UPDATE (1 << 7)
+#define UVC_CTRL_FLAG_ASYNCHRONOUS (1 << 8)
 #define UVC_CTRL_FLAG_GET_RANGE (UVC_CTRL_FLAG_GET_CUR | UVC_CTRL_FLAG_GET_MIN | UVC_CTRL_FLAG_GET_MAX | UVC_CTRL_FLAG_GET_RES | UVC_CTRL_FLAG_GET_DEF)
 struct uvc_menu_info {
   __u32 value;