diff --git a/Documentation/devicetree/bindings/phy/samsung,usb3-drd-phy.yaml b/Documentation/devicetree/bindings/phy/samsung,usb3-drd-phy.yaml
index 2f457f8b13e8..4562e0468f4f 100644
--- a/Documentation/devicetree/bindings/phy/samsung,usb3-drd-phy.yaml
+++ b/Documentation/devicetree/bindings/phy/samsung,usb3-drd-phy.yaml
@@ -54,6 +54,9 @@ properties:
           settings register.  For Exynos5420 this is given as 'sclk_usbphy30'
           in the CMU. It's not needed for Exynos2200.
 
+  power-domains:
+    maxItems: 1
+
   "#phy-cells":
     const: 1