dt-bindings: iio: adc: Add AD7949 device tree bindings in documentation

Description how to invoke ad7949 driver from device tree file.

Signed-off-by: Charles-Antoine Couret <charles-antoine.couret@essensium.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/Documentation/devicetree/bindings/iio/adc/ad7949.txt b/Documentation/devicetree/bindings/iio/adc/ad7949.txt
new file mode 100644 (file)
index 0000000..c7f5057
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/ad7949.txt
@@ -0,0 +1,16 @@
+* Analog Devices AD7949/AD7682/AD7689
+
+Required properties:
+ - compatible: Should be one of
+       * "adi,ad7949"
+       * "adi,ad7682"
+       * "adi,ad7689"
+ - reg: spi chip select number for the device
+ - vref-supply: The regulator supply for ADC reference voltage
+
+Example:
+adc@0 {
+       compatible = "adi,ad7949";
+       reg = <0>;
+       vref-supply = <&vdd_supply>;
+};