diff --git a/doc/device-tree-bindings/usb/mediatek,mtk-xhci.txt b/doc/device-tree-bindings/usb/mediatek,mtk-xhci.txt
index 0447468a2d..2a298f7b16 100644
--- a/doc/device-tree-bindings/usb/mediatek,mtk-xhci.txt
+++ b/doc/device-tree-bindings/usb/mediatek,mtk-xhci.txt
@@ -25,6 +25,10 @@ Required properties:
 
 Optional properties:
  - vbus-supply : reference to the VBUS regulator;
+ - mediatek,u3p-dis-msk : mask to disable u3ports, bit0 for u3port0,
+	bit1 for u3port1, ... etc;
+ - mediatek,u2p-dis-msk : mask to disable u2ports, bit0 for u2port0,
+	bit1 for u2port1, ... etc;
 
 Example:
 xhci: usb@1a0c0000 {