diff --git a/Documentation/devicetree/bindings/power/twl-charger.txt b/Documentation/devicetree/bindings/power/twl-charger.txt
index 3b4ea1b..e198650 100644
--- a/Documentation/devicetree/bindings/power/twl-charger.txt
+++ b/Documentation/devicetree/bindings/power/twl-charger.txt
@@ -19,12 +19,18 @@ Required properties:
 Optional properties:
 - ti,bb-uvolt: microvolts for charging the backup battery.
 - ti,bb-uamp: microamps for charging the backup battery.
+- io-channels: Should contain following: <&twl4030_madc 11>
+- io-channel-names: Should contains following value:
+	* "vac" - ADC channel for measuring the voltage of the external AC charger
+If io properties aren't provided then functionality of accesory charger doesn't work.
 
 Examples:
 
 bci {
    compatible = "ti,twl4030-bci";
    interrupts = <9>, <2>;
+   io-channels = <&twl4030_madc 11>;
+   io-channel-name = "vac";
    ti,bb-uvolt = <3200000>;
    ti,bb-uamp = <150>;
 };