diff --git a/Documentation/devicetree/bindings/serial/rs485.yaml b/Documentation/devicetree/bindings/serial/rs485.yaml
index 303a443d9e29b2266d66992e1a71546b19d6b23c..9418fd66a8e95a94066720be9e5f28c32b6e0665 100644
--- a/Documentation/devicetree/bindings/serial/rs485.yaml
+++ b/Documentation/devicetree/bindings/serial/rs485.yaml
@@ -29,6 +29,10 @@ properties:
           default: 0
           maximum: 100
 
+  rs485-rts-active-high:
+    description: drive RTS high when sending (this is the default).
+    $ref: /schemas/types.yaml#/definitions/flag
+
   rs485-rts-active-low:
     description: drive RTS low when sending (default is high).
     $ref: /schemas/types.yaml#/definitions/flag