dt-bindings: adc: add AD7173

# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)

# Copyright 2023 Analog Devices Inc.

%YAML 1.2

---

$id: http://devicetree.org/schemas/iio/adc/adi,ad7173.yaml#

$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Analog Devices AD7173 ADC

maintainers:

  - Ceclan Dumitru <dumitru.ceclan@analog.com>

description: |

  Analog Devices AD717x ADC's:

  The AD717x family offer a complete integrated Sigma-Delta ADC solution which

  can be used in high precision, low noise single channel applications

  (Life Science measurements) or higher speed multiplexed applications

  (Factory Automation PLC Input modules). The Sigma-Delta ADC is intended

  primarily for measurement of signals close to DC but also delivers

  outstanding performance with input bandwidths out to ~10kHz.

  Datasheets for supported chips:

    https://www.analog.com/media/en/technical-documentation/data-sheets/AD7172-2.pdf

    https://www.analog.com/media/en/technical-documentation/data-sheets/AD7173-8.pdf

    https://www.analog.com/media/en/technical-documentation/data-sheets/AD7175-2.pdf

    https://www.analog.com/media/en/technical-documentation/data-sheets/AD7176-2.pdf

properties:

  compatible:

    enum:

      - adi,ad7172-2

      - adi,ad7173-8

      - adi,ad7175-2

      - adi,ad7176-2

  reg:

    maxItems: 1

  interrupts:

    minItems: 1

    items:

      - description: |

          Ready: multiplexed with SPI data out. While SPI CS is low,

          can be used to indicate the completion of a conversion.

      - description: |

          Error: The three error bits in the status register (ADC_ERROR, CRC_ERROR,

          and REG_ERROR) are OR'ed, inverted, and mapped to the ERROR pin.

          Therefore, the ERROR pin indicates that an error has occurred.

  interrupt-names:

    minItems: 1

    items:

      - const: rdy

      - const: err

  '#address-cells':

    const: 1

  '#size-cells':

    const: 0

  spi-max-frequency:

    maximum: 20000000

  gpio-controller:

    description: Marks the device node as a GPIO controller.

  '#gpio-cells':

    const: 2

    description:

      The first cell is the GPIO number and the second cell specifies

      GPIO flags, as defined in <dt-bindings/gpio/gpio.h>.

  vref-supply:

    description: |

      Differential external reference supply used for conversion. The reference

      voltage (Vref) specified here must be the voltage difference between the

      REF+ and REF- pins: Vref = (REF+) - (REF-).

  vref2-supply:

    description: |

      Differential external reference supply used for conversion. The reference

      voltage (Vref2) specified here must be the voltage difference between the

      REF2+ and REF2- pins: Vref2 = (REF2+) - (REF2-).

  avdd-supply:

    description: Avdd supply, can be used as reference for conversion.

                 This supply is referenced to AVSS, voltage specified here

                 represents (AVDD1 - AVSS).

  avdd2-supply:

    description: Avdd2 supply, used as the input to the internal voltage regulator.

                 This supply is referenced to AVSS, voltage specified here

                 represents (AVDD2 - AVSS).

  iovdd-supply:

    description: iovdd supply, used for the chip digital interface.

  clocks:

    maxItems: 1

    description: |

      Optional external clock source. Can include one clock source: external

      clock or external crystal.

  clock-names:

    enum:

      - ext-clk

      - xtal

  '#clock-cells':

    const: 0

patternProperties:

  "^channel@[0-9a-f]$":

    type: object

    $ref: adc.yaml

    unevaluatedProperties: false

    properties:

      reg:

        minimum: 0

        maximum: 15

      diff-channels:

        items:

          minimum: 0

          maximum: 31

      adi,reference-select:

        description: |

          Select the reference source to use when converting on

          the specific channel. Valid values are:

          vref       : REF+  /REF−

          vref2      : REF2+ /REF2−

          refout-avss: REFOUT/AVSS (Internal reference)

          avdd       : AVDD  /AVSS

          External reference ref2 only available on ad7173-8.

          If not specified, internal reference used.

        $ref: /schemas/types.yaml#/definitions/string

        enum:

          - vref

          - vref2

          - refout-avss

          - avdd

        default: refout-avss

    required:

      - reg

      - diff-channels

required:

  - compatible

  - reg

allOf:

  - $ref: /schemas/spi/spi-peripheral-props.yaml#

  - if:

      properties:

        compatible:

          not:

            contains:

              const: adi,ad7173-8

    then:

      properties:

        vref2-supply: false

      patternProperties:

        "^channel@[0-9a-f]$":

          properties:

            adi,reference-select:

              enum:

                - vref

                - refout-avss

                - avdd

            reg:

              maximum: 3

  - if:

      anyOf:

        - required: [clock-names]

        - required: [clocks]

    then:

      properties:

        '#clock-cells': false

unevaluatedProperties: false

examples:

  - |

    #include <dt-bindings/gpio/gpio.h>

    #include <dt-bindings/interrupt-controller/irq.h>

    spi {

      #address-cells = <1>;

      #size-cells = <0>;

      adc@0 {

        compatible = "adi,ad7173-8";

        reg = <0>;

        #address-cells = <1>;

        #size-cells = <0>;

        interrupts = <25 IRQ_TYPE_EDGE_FALLING>;

        interrupt-names = "rdy";

        interrupt-parent = <&gpio>;

        spi-max-frequency = <5000000>;

        gpio-controller;

        #gpio-cells = <2>;

        #clock-cells = <0>;

        vref-supply = <&dummy_regulator>;

        channel@0 {

          reg = <0>;

          bipolar;

          diff-channels = <0 1>;

          adi,reference-select = "vref";

        };

        channel@1 {

          reg = <1>;

          diff-channels = <2 3>;

        };

        channel@2 {

          reg = <2>;

          bipolar;

          diff-channels = <4 5>;

        };

        channel@3 {

          reg = <3>;

          bipolar;

          diff-channels = <6 7>;

        };

        channel@4 {

          reg = <4>;

          diff-channels = <8 9>;

          adi,reference-select = "avdd";

        };

      };

    };