dt-bindings: iio: dac: Add ti,dac7311 device tree bindings in documentation

Description how to invoke ti-dac7311 driver from device tree file.

Signed-off-by: Charles-Antoine Couret <charles-antoine.couret@essensium.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/Documentation/devicetree/bindings/iio/dac/ti,dac7311.txt b/Documentation/devicetree/bindings/iio/dac/ti,dac7311.txt
new file mode 100644 (file)
index 0000000..e5a507d
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/dac/ti,dac7311.txt
@@ -0,0 +1,23 @@
+TI DAC7311 device tree bindings
+
+Required properties:
+- compatible: must be set to:
+       * "ti,dac7311"
+       * "ti,dac6311"
+       * "ti,dac5311"
+- reg: spi chip select number for the device
+- vref-supply: The regulator supply for ADC reference voltage
+
+Optional properties:
+- spi-max-frequency: Max SPI frequency to use
+
+Example:
+
+       spi_master {
+               dac@0 {
+                       compatible = "ti,dac7311";
+                       reg = <0>; /* CS0 */
+                       spi-max-frequency = <1000000>;
+                       vref-supply = <&vdd_supply>;
+               };
+       };