diff --git a/Documentation/devicetree/bindings/sound/rockchip-i2s.yaml b/Documentation/devicetree/bindings/sound/rockchip-i2s.yaml
index 1cb4da300607..c32b4750651c 100644
--- a/Documentation/devicetree/bindings/sound/rockchip-i2s.yaml
+++ b/Documentation/devicetree/bindings/sound/rockchip-i2s.yaml
@@ -82,6 +82,10 @@ properties:
   resets:
     maxItems: 2
 
+  port:
+    $ref: audio-graph-port.yaml#
+    unevaluatedProperties: false
+
   rockchip,capture-channels:
     $ref: /schemas/types.yaml#/definitions/uint32
     default: 2