Documentation: DT: Document rx51-battery binding

Add devicetree binding documentation for rx51-battery,
which is a simple A/D converter consumer.

Signed-off-by: Sebastian Reichel <sre@kernel.org>

1 files changed, 25 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/power/rx51-battery.txt b/Documentation/devicetree/bindings/power/rx51-battery.txt
new file mode 100644
index 000000000000..90438453db58
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/rx51-battery.txt
@@ -0,0 +1,25 @@
+Binding for Nokia N900 battery
+
+The Nokia N900 battery status can be read via the TWL4030's A/D converter.
+
+Required properties:
+- compatible: Should contain one of the following:
+ * "nokia,n900-battery"
+- io-channels: Should contain IIO channel specifiers
+               for each element in io-channel-names.
+- io-channel-names: Should contain the following values:
+ * "temp" - The ADC channel for temperature reading
+ * "bsi"  - The ADC channel for battery size identification
+ * "vbat" - The ADC channel to measure the battery voltage
+
+Example from Nokia N900:
+
+battery: n900-battery {
+        compatible = "nokia,n900-battery";
+        io-channels = <&twl4030_madc 0>,
+                      <&twl4030_madc 4>,
+                      <&twl4030_madc 12>;
+        io-channel-names = "temp",
+                           "bsi",
+                           "vbat";
+};