dt-bindings: iio: adc: Add docs for ad7124

Add support for Analog Devices AD7124 4-channels and 8-channels ADC.

Signed-off-by: Stefan Popa <stefan.popa@analog.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7124.txt b/Documentation/devicetree/bindings/iio/adc/adi,ad7124.txt
new file mode 100644 (file)
index 0000000..416273d
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7124.txt
@@ -0,0 +1,75 @@
+Analog Devices AD7124 ADC device driver
+
+Required properties for the AD7124:
+       - compatible: Must be one of "adi,ad7124-4" or "adi,ad7124-8"
+       - reg: SPI chip select number for the device
+       - spi-max-frequency: Max SPI frequency to use
+               see: Documentation/devicetree/bindings/spi/spi-bus.txt
+       - clocks: phandle to the master clock (mclk)
+               see: Documentation/devicetree/bindings/clock/clock-bindings.txt
+       - clock-names: Must be "mclk".
+       - interrupts: IRQ line for the ADC
+               see: Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
+
+         Required properties:
+               * #address-cells: Must be 1.
+               * #size-cells: Must be 0.
+
+         Subnode(s) represent the external channels which are connected to the ADC.
+         Each subnode represents one channel and has the following properties:
+               Required properties:
+                       * reg: The channel number. It can have up to 4 channels on ad7124-4
+                         and 8 channels on ad7124-8, numbered from 0 to 15.
+                       * diff-channels: see: Documentation/devicetree/bindings/iio/adc/adc.txt
+
+               Optional properties:
+                       * bipolar: see: Documentation/devicetree/bindings/iio/adc/adc.txt
+                       * adi,reference-select: Select the reference source to use when
+                         converting on the the specific channel. Valid values are:
+                         0: REFIN1(+)/REFIN1(−).
+                         1: REFIN2(+)/REFIN2(−).
+                         3: AVDD
+                         If this field is left empty, internal reference is selected.
+
+Optional properties:
+       - refin1-supply: refin1 supply can be used as reference for conversion.
+       - refin2-supply: refin2 supply can be used as reference for conversion.
+       - avdd-supply: avdd supply can be used as reference for conversion.
+
+Example:
+       adc@0 {
+               compatible = "adi,ad7124-4";
+               reg = <0>;
+               spi-max-frequency = <5000000>;
+               interrupts = <25 2>;
+               interrupt-parent = <&gpio>;
+               refin1-supply = <&adc_vref>;
+               clocks = <&ad7124_mclk>;
+               clock-names = "mclk";
+
+               #address-cells = <1>;
+               #size-cells = <0>;
+
+               channel@0 {
+                       reg = <0>;
+                       diff-channels = <0 1>;
+                       adi,reference-select = <0>;
+               };
+
+               channel@1 {
+                       reg = <1>;
+                       bipolar;
+                       diff-channels = <2 3>;
+                       adi,reference-select = <0>;
+               };
+
+               channel@2 {
+                       reg = <2>;
+                       diff-channels = <4 5>;
+               };
+
+               channel@3 {
+                       reg = <3>;
+                       diff-channels = <6 7>;
+               };
+       };

diff --git a/MAINTAINERS b/MAINTAINERS
index 457f29b..1fe69e3 100644 (file)
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -845,6 +845,7 @@ L:  linux-iio@vger.kernel.org
 W:     http://ez.analog.com/community/linux-device-drivers
 S:     Supported
 F:     drivers/iio/adc/ad7124.c
+F:     Documentation/devicetree/bindings/iio/adc/adi,ad7124.txt
 
 ANALOG DEVICES INC AD9389B DRIVER
 M:     Hans Verkuil <hans.verkuil@cisco.com>