diff --git a/Documentation/devicetree/bindings/mailbox/apple,mailbox.yaml b/Documentation/devicetree/bindings/mailbox/apple,mailbox.yaml
index bdf58f03b848..28985cc62c25 100644
--- a/Documentation/devicetree/bindings/mailbox/apple,mailbox.yaml
+++ b/Documentation/devicetree/bindings/mailbox/apple,mailbox.yaml
@@ -31,6 +31,7 @@ properties:
               - apple,t8103-asc-mailbox
               - apple,t8112-asc-mailbox
               - apple,t6000-asc-mailbox
+              - apple,t6020-asc-mailbox
           - const: apple,asc-mailbox-v4
 
       - description: