diff --git a/Documentation/devicetree/bindings/input/touchscreen/mstar,msg2638.yaml b/Documentation/devicetree/bindings/input/touchscreen/mstar,msg2638.yaml
index 2fb7e01bb65a..af4f954de958 100644
--- a/Documentation/devicetree/bindings/input/touchscreen/mstar,msg2638.yaml
+++ b/Documentation/devicetree/bindings/input/touchscreen/mstar,msg2638.yaml
@@ -36,6 +36,10 @@ properties:
   touchscreen-size-x: true
   touchscreen-size-y: true
 
+  linux,keycodes:
+    minItems: 1
+    maxItems: 4
+
 additionalProperties: false
 
 required: