diff --git a/Documentation/devicetree/bindings/usb/mediatek,mtu3.txt b/Documentation/devicetree/bindings/usb/mediatek,mtu3.txt
index 49f54767cd214e8d6d4ada2dcd1e133aa6ede4cc..7c611d14a0a056098d81aef26d97ba3e3c0897f8 100644
--- a/Documentation/devicetree/bindings/usb/mediatek,mtu3.txt
+++ b/Documentation/devicetree/bindings/usb/mediatek,mtu3.txt
@@ -44,6 +44,8 @@ Optional properties:
  - mediatek,enable-wakeup : supports ip sleep wakeup used by host mode
  - mediatek,syscon-wakeup : phandle to syscon used to access USB wakeup
 	control register, it depends on "mediatek,enable-wakeup".
+ - mediatek,u3p-dis-msk : mask to disable u3ports, bit0 for u3port0,
+	bit1 for u3port1, ... etc;
 
 Sub-nodes:
 The xhci should be added as subnode to mtu3 as shown in the following example