diff --git a/Documentation/devicetree/bindings/pinctrl/nuvoton,npcm845-pinctrl.yaml b/Documentation/devicetree/bindings/pinctrl/nuvoton,npcm845-pinctrl.yaml
index e4b9f3da2cf0..3e8472898800 100644
--- a/Documentation/devicetree/bindings/pinctrl/nuvoton,npcm845-pinctrl.yaml
+++ b/Documentation/devicetree/bindings/pinctrl/nuvoton,npcm845-pinctrl.yaml
@@ -35,6 +35,7 @@ properties:
 patternProperties:
   '^gpio@':
     type: object
+    additionalProperties: false
 
     description:
       Eight GPIO banks that each contain 32 GPIOs.