staging: iio: ad5933: add binding doc for ad5933

Add a devicetree documentation for the ad5933 and ad5934 impedance
converter, network analyzer.

Signed-off-by: Marcelo Schmitt <marcelo.schmitt1@gmail.com>
Signed-off-by: Gabriel Capella <gabriel@capella.pro>
Co-Developed-by: Gabriel Capella <gabriel@capella.pro>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/Documentation/devicetree/bindings/iio/impedance-analyzer/ad5933.txt b/Documentation/devicetree/bindings/iio/impedance-analyzer/ad5933.txt
new file mode 100644 (file)
index 0000000..5ff3872
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+++ b/Documentation/devicetree/bindings/iio/impedance-analyzer/ad5933.txt
@@ -0,0 +1,26 @@
+Analog Devices AD5933/AD5934 Impedance Converter, Network Analyzer
+
+https://www.analog.com/media/en/technical-documentation/data-sheets/AD5933.pdf
+https://www.analog.com/media/en/technical-documentation/data-sheets/AD5934.pdf
+
+Required properties:
+ - compatible : should be one of
+               "adi,ad5933"
+               "adi,ad5934"
+ - reg : the I2C address.
+ - vdd-supply : The regulator supply for DVDD, AVDD1 and AVDD2 when they
+   are connected together.
+
+Optional properties:
+- clocks : external clock reference.
+- clock-names : must be "mclk" if clocks is set.
+
+Example for a I2C device node:
+
+       impedance-analyzer@0d {
+               compatible = "adi,adxl345";
+               reg = <0x0d>;
+               vdd-supply = <&vdd_supply>;
+               clocks = <&ref_clk>;
+               clock-names = "mclk";
+       };