[PATCH v2] dt-bindings: iio: adc: add a7779 doc

[ranechita]

Add dt bindings for adc ad7779.

Signed-off-by: Ramona Alexandra Nechita <ramona.nechita@xxxxxxxxxx>
---
 .../ABI/testing/sysfs-bus-iio-adc-ad777x      | 23 +++++
 .../bindings/iio/adc/adi,ad7779.yaml          | 87 +++++++++++++++++++
 2 files changed, 110 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-adc-ad777x
 create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad7779.yaml

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-adc-ad777x b/Documentation/ABI/testing/sysfs-bus-iio-adc-ad777x
new file mode 100644
index 000000000000..0a57fda598e6
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-iio-adc-ad777x
@@ -0,0 +1,23 @@
+What:		/sys/bus/iio/devices/iio:deviceX/filter_type_available
+KernelVersion:  6.1
+Contact:	linux-iio@xxxxxxxxxxxxxxx
+Description:
+		Reading returns a list with the possible filter modes. Only supported by
+		AD7771.
+
+		  * "sinc3"	- The digital sinc3 filter implements three main notches, one at
+				the maximum ODR (128 kHz or 32 kHz, depending on the
+				power mode) and another two at the ODR frequency selected to
+				stop noise aliasing into the pass band.
+
+		  * "sinc5"	- The sinc5 filter implements five notches, one at
+				the maximum ODR (128 kHz or 32 kHz, depending on the
+				power mode) and another four at the ODR frequency
+				selected to stop noise aliasing into the pass band.
+
+What:		/sys/bus/iio/devices/iio:deviceX/filter_type
+KernelVersion:  6.1
+Contact:	linux-iio@xxxxxxxxxxxxxxx
+Description:
+		Set the filter mode of the differential channel. The current sampling_frequency
+		is set according to the filter range. Only supported by AD7771.
diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7779.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7779.yaml
new file mode 100644
index 000000000000..632e9ec0ab44
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7779.yaml
@@ -0,0 +1,87 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/adc/adi,ad7779.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices AD777X family 8-Channel, 24-Bit, Simultaneous Sampling ADCs
+
+maintainers:
+  - Ramona Nechita <ramona.nechita@xxxxxxxxxx>
+
+description: |
+  The AD777X family consist of 8-channel, simultaneous sampling analog-to-
+  digital converter (ADC). Eight full Σ-Δ ADCs are on-chip. The
+  AD7771 provides an ultralow input current to allow direct sensor
+  connection. Each input channel has a programmable gain stage
+  allowing gains of 1, 2, 4, and 8 to map lower amplitude sensor
+  outputs into the full-scale ADC input range, maximizing the
+  dynamic range of the signal chain.
+
+  https://www.analog.com/media/en/technical-documentation/data-sheets/ad7770.pdf
+  https://www.analog.com/media/en/technical-documentation/data-sheets/ad7771.pdf
+  https://www.analog.com/media/en/technical-documentation/data-sheets/ad7779.pdf
+
+$ref: /schemas/spi/spi-peripheral-props.yaml#
+
+properties:
+  compatible:
+    enum:
+      - adi,ad7770
+      - adi,ad7771
+      - adi,ad7779
+
+  reg:
+    maxItems: 1
+
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 0
+
+  spi-max-frequency: true
+
+  clocks:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  vref-supply:
+    description:
+      ADC reference voltage supply
+
+  start-gpios:
+    description:
+      Pin that controls start synchronization pulse.
+    maxItems: 1
+
+  reset-gpios:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - clocks
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        adc@0 {
+          compatible = "adi,ad7779";
+          reg = <0>;
+          spi-max-frequency = <20000000>;
+          vref-supply = <&vref>;
+          start-gpios = <&gpio0 87 GPIO_ACTIVE_LOW>;
+          reset-gpios = <&gpio0 93 GPIO_ACTIVE_LOW>;
+          clocks = <&adc_clk>;
+        };
+    };
+...
-- 
2.43.0