diff --git a/Documentation/devicetree/bindings/serial/samsung_uart.yaml b/Documentation/devicetree/bindings/serial/samsung_uart.yaml
index 133259ed3a34..0f0131026911 100644
--- a/Documentation/devicetree/bindings/serial/samsung_uart.yaml
+++ b/Documentation/devicetree/bindings/serial/samsung_uart.yaml
@@ -143,6 +143,8 @@ allOf:
     then:
       required:
         - samsung,uart-fifosize
+      properties:
+        reg-io-width: false
 
 unevaluatedProperties: false