iio:dac: Add support for the AD7303

This patch adds support for the AD7303. The AD7303 is a simple 2 channel 8 bit
DAC with an SPI interface.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

1 files changed, 23 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/iio/dac/ad7303.txt b/Documentation/devicetree/bindings/iio/dac/ad7303.txt
new file mode 100644
index 000000000000..914610f0556e
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/dac/ad7303.txt
@@ -0,0 +1,23 @@
+Analog Devices AD7303 DAC device driver
+
+Required properties:
+	- compatible: Must be "adi,ad7303"
+	- reg: SPI chip select number for the device
+	- spi-max-frequency: Max SPI frequency to use (< 30000000)
+	- Vdd-supply: Phandle to the Vdd power supply
+
+Optional properties:
+	- REF-supply: Phandle to the external reference voltage supply. This should
+	  only be set if there is an external reference voltage connected to the REF
+	  pin. If the property is not set Vdd/2 is used as the reference voltage.
+
+Example:
+
+		ad7303@4 {
+			compatible = "adi,ad7303";
+			reg = <4>;
+			spi-max-frequency = <10000000>;
+			Vdd-supply = <&vdd_supply>;
+			adi,use-external-reference;
+			REF-supply = <&vref_supply>;
+		};