diff --git a/Documentation/devicetree/bindings/regulator/mediatek,mt6331-regulator.yaml b/Documentation/devicetree/bindings/regulator/mediatek,mt6331-regulator.yaml
index c654acf13768..eb16e53cb5bf 100644
--- a/Documentation/devicetree/bindings/regulator/mediatek,mt6331-regulator.yaml
+++ b/Documentation/devicetree/bindings/regulator/mediatek,mt6331-regulator.yaml
@@ -40,13 +40,13 @@ patternProperties:
 
     unevaluatedProperties: false
 
-  "^ldo-v(dig18|emc33|ibr|mc|mch|mipi|rtc|sim1|sim2|sram|usb10)$":
+  "^ldo-v(dig18|emc33|ibr|io28|mc|mch|mipi|rtc|sim1|sim2|sram|usb10)$":
     type: object
     $ref: regulator.yaml#
 
     properties:
       regulator-name:
-        pattern: "^v(dig18|emc33|ibr|mc|mch|mipi|rtc|sim1|sim2|sram|usb)$"
+        pattern: "^v(dig18|emc33|ibr|io28|mc|mch|mipi|rtc|sim1|sim2|sram|usb)$"
 
     unevaluatedProperties: false