diff --git a/Documentation/devicetree/bindings/phy/phy-mtk-tphy.txt b/Documentation/devicetree/bindings/phy/phy-mtk-tphy.txt
index 0d34b2b4a6b79600906515679ec45771359d11ac..a5f7a4f0dbc1a8609270b32b761a447183222a57 100644
--- a/Documentation/devicetree/bindings/phy/phy-mtk-tphy.txt
+++ b/Documentation/devicetree/bindings/phy/phy-mtk-tphy.txt
@@ -47,6 +47,12 @@ Required properties (port (child) node):
 			- PHY_TYPE_PCIE
 			- PHY_TYPE_SATA
 
+Optional properties (PHY_TYPE_USB2 port (child) node):
+- mediatek,eye-src	: u32, the value of slew rate calibrate
+- mediatek,eye-vrt	: u32, the selection of VRT reference voltage
+- mediatek,eye-term	: u32, the selection of HS_TX TERM reference voltage
+- mediatek,bc12	: bool, enable BC12 of u2phy if support it
+
 Example:
 
 u3phy: usb-phy@11290000 {