diff --git a/Documentation/devicetree/bindings/sound/ak5558.txt b/Documentation/devicetree/bindings/sound/ak5558.txt
index 7d67ca6ced80..36934098170c 100644
--- a/Documentation/devicetree/bindings/sound/ak5558.txt
+++ b/Documentation/devicetree/bindings/sound/ak5558.txt
@@ -10,6 +10,8 @@ Required properties:
 Optional properties:
 
 - reset-gpios: A GPIO specifier for the power down & reset pin.
+- AVDD-supply: Analog power supply
+- DVDD-supply: Digital power supply
 
 Example: