[PATCH v9 1/2] dt-bindings: iio: adc: add AD4130

[Cosmin Tanislav]

AD4130-8 is an ultra-low power, high precision, measurement solution for
low bandwidth battery operated applications.

The fully integrated AFE (Analog Front-End) includes a multiplexer for up
to 16 single-ended or 8 differential inputs, PGA (Programmable Gain
Amplifier), 24-bit Sigma-Delta ADC, on-chip reference and oscillator,
selectable filter options, smart sequencer, sensor biasing and excitation
options, diagnostics, and a FIFO buffer.

Signed-off-by: Cosmin Tanislav <cosmin.tanislav@xxxxxxxxxx>
Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
---
 .../bindings/iio/adc/adi,ad4130.yaml          | 252 ++++++++++++++++++
 1 file changed, 252 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad4130.yaml

diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad4130.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad4130.yaml
new file mode 100644
index 000000000000..dea7426095c6
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad4130.yaml
@@ -0,0 +1,252 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+# Copyright 2022 Analog Devices Inc.
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/adc/adi,ad4130.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices AD4130 ADC device driver
+
+maintainers:
+  - Cosmin Tanislav <cosmin.tanislav@xxxxxxxxxx>
+
+description: |
+  Bindings for the Analog Devices AD4130 ADC. Datasheet can be found here:
+    https://www.analog.com/media/en/technical-documentation/data-sheets/AD4130-8.pdf
+
+properties:
+  compatible:
+    enum:
+      - adi,ad4130
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+    description: phandle to the master clock (mclk)
+
+  clock-names:
+    items:
+      - const: mclk
+
+  interrupts:
+    maxItems: 1
+
+  interrupt-names:
+    description: |
+      Specify which interrupt pin should be configured as Data Ready / FIFO
+      interrupt.
+      Default if not supplied is int.
+    enum:
+      - int
+      - clk
+      - p2
+      - dout
+
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 0
+
+  refin1-supply:
+    description: refin1 supply. Can be used as reference for conversion.
+
+  refin2-supply:
+    description: refin2 supply. Can be used as reference for conversion.
+
+  avdd-supply:
+    description: AVDD voltage supply. Can be used as reference for conversion.
+
+  iovdd-supply:
+    description: IOVDD voltage supply. Used for the chip interface.
+
+  spi-max-frequency:
+    maximum: 5000000
+
+  adi,ext-clk-freq-hz:
+    description: Specify the frequency of the external clock.
+    enum: [76800, 153600]
+    default: 76800
+
+  adi,bipolar:
+    description: Specify if the device should be used in bipolar mode.
+    type: boolean
+
+  adi,vbias-pins:
+    description: Analog inputs to apply a voltage bias of (AVDD − AVSS) / 2 to.
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+    maxItems: 16
+    items:
+      minimum: 0
+      maximum: 15
+
+required:
+  - compatible
+  - reg
+  - interrupts
+
+patternProperties:
+  "^channel@([0-9a-f])$":
+    type: object
+    $ref: adc.yaml
+    unevaluatedProperties: false
+
+    properties:
+      reg:
+        description: The channel number.
+        minimum: 0
+        maximum: 15
+
+      diff-channels:
+        description: |
+          Besides the analog inputs available, internal inputs can be used.
+          16: Internal temperature sensor.
+          17: AVSS
+          18: Internal reference
+          19: DGND
+          20: (AVDD − AVSS)/6+
+          21: (AVDD − AVSS)/6-
+          22: (IOVDD − DGND)/6+
+          23: (IOVDD − DGND)/6-
+          24: (ALDO − AVSS)/6+
+          25: (ALDO − AVSS)/6-
+          26: (DLDO − DGND)/6+
+          27: (DLDO − DGND)/6-
+          28: V_MV_P
+          29: V_MV_M
+        items:
+          minimum: 0
+          maximum: 29
+
+      adi,reference-select:
+        description: |
+          Select the reference source to use when converting on the
+          specific channel. Valid values are:
+          0: REFIN1(+)/REFIN1(−)
+          1: REFIN2(+)/REFIN2(−)
+          2: REFOUT/AVSS (Internal reference)
+          3: AVDD/AVSS
+          If not specified, REFIN1 is used.
+        $ref: /schemas/types.yaml#/definitions/uint32
+        enum: [0, 1, 2, 3]
+        default: 0
+
+      adi,excitation-pin-0:
+        description: |
+          Analog input to apply excitation current to while the channel
+          is active.
+        $ref: /schemas/types.yaml#/definitions/uint32
+        minimum: 0
+        maximum: 15
+        default: 0
+
+      adi,excitation-pin-1:
+        description: |
+          Analog input to apply excitation current to while this channel
+          is active.
+        $ref: /schemas/types.yaml#/definitions/uint32
+        minimum: 0
+        maximum: 15
+        default: 0
+
+      adi,excitation-current-0-nanoamp:
+        description: |
+          Excitation current in nanoamps to be applied to pin specified in
+          adi,excitation-pin-0 while this channel is active.
+        enum: [0, 100, 10000, 20000, 50000, 100000, 150000, 200000]
+        default: 0
+
+      adi,excitation-current-1-nanoamp:
+        description: |
+          Excitation current in nanoamps to be applied to pin specified in
+          adi,excitation-pin-1 while this channel is active.
+        enum: [0, 100, 10000, 20000, 50000, 100000, 150000, 200000]
+        default: 0
+
+      adi,burnout-current-nanoamp:
+        description: |
+          Burnout current in nanoamps to be applied for this channel.
+        enum: [0, 500, 2000, 4000]
+        default: 0
+
+      adi,buffered-positive:
+        description: Enable buffered mode for positive input.
+        type: boolean
+
+      adi,buffered-negative:
+        description: Enable buffered mode for negative input.
+        type: boolean
+
+    required:
+      - reg
+      - diff-channels
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    spi {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      adc@0 {
+        compatible = "adi,ad4130";
+        reg = <0>;
+
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        spi-max-frequency = <5000000>;
+        interrupts = <27 IRQ_TYPE_EDGE_FALLING>;
+        interrupt-parent = <&gpio>;
+
+        channel@0 {
+          reg = <0>;
+
+          adi,reference-select = <2>;
+
+          /* AIN8, AIN9 */
+          diff-channels = <8 9>;
+        };
+
+        channel@1 {
+          reg = <1>;
+
+          adi,reference-select = <2>;
+
+          /* AIN10, AIN11 */
+          diff-channels = <10 11>;
+        };
+
+        channel@2 {
+          reg = <2>;
+
+          adi,reference-select = <2>;
+
+          /* Temperature Sensor, DGND */
+          diff-channels = <16 19>;
+        };
+
+        channel@3 {
+          reg = <3>;
+
+          adi,reference-select = <2>;
+
+          /* Internal reference, DGND */
+          diff-channels = <18 19>;
+        };
+
+        channel@4 {
+          reg = <4>;
+
+          adi,reference-select = <2>;
+
+          /* DGND, DGND */
+          diff-channels = <19 19>;
+        };
+      };
+    };
-- 
2.38.0