Re: [PATCH v2 1/2] dt-bindings: iio: adc: ti,ads112c04: Add binding for ADS112C04

[David Lechner <dlechner@baylibre.com>]

On 7/30/26 9:58 PM, Kyle Hsieh wrote:
> Add device tree binding documentation for Texas Instruments ADS112C04
> I2C Analog-to-Digital Converters.
> 
> These devices provide 4-channel, 16-bit delta-sigma ADCs with an I2C
> interface, programmable gain amplifier (PGA), and data-ready (DRDY)
> interrupt output.
> 
> The binding uses child nodes to dynamically define the connected
> single-ended or differential channels.
> 
> Signed-off-by: Kyle Hsieh <kylehsieh1995@gmail.com>
> ---
>  .../devicetree/bindings/iio/adc/ti,ads112c04.yaml  | 122 +++++++++++++++++++++
>  1 file changed, 122 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/iio/adc/ti,ads112c04.yaml b/Documentation/devicetree/bindings/iio/adc/ti,ads112c04.yaml
> new file mode 100644
> index 000000000000..6a5ffda84b80
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/ti,ads112c04.yaml
> @@ -0,0 +1,122 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/adc/ti,ads112c04.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Texas Instruments ADS112C04 ADC
> +
> +maintainers:
> +  - Kyle Hsieh <kylehsieh1995@gmail.com>
> +
> +description: |

The | isn't needed in this case. (It is only needed if we needed
to preserve formatting, or if there is a : in the text that would
be interpreted as a dict key.)

> +  The ADS112C04 (16-bit) are precision analog-to-digital converters (ADCs)
> +  with an I2C interface. They feature a flexible input multiplexer, a
> +  low-noise programmable gain amplifier (PGA), two programmable excitation
> +  current sources, a voltage reference, and a precision temperature sensor.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - ti,ads112c04
> +
> +  reg:
> +    maxItems: 1
> +    description: I2C address of the device.
> +
> +  interrupts:
> +    maxItems: 1
> +    description: Data ready (DRDY) interrupt output.
> +
> +  "#address-cells":
> +    const: 1
> +
> +  "#size-cells":
> +    const: 0
> +
> +  reset-gpios:
> +    maxItems: 1
> +    description: GPIO connected to the RESET pin. Active low.
> +
> +  avdd-supply: true
> +  dvdd-supply: true
> +
> +  refp-supply: true
> +  refn-supply: true
> +
> +  ti,refp-refn-resistor-ohms:
> +    $ref: /schemas/types.yaml#/definitions/uint32

As the bot said, don't need $ref here because it is a standard unit.
(So don't forget to run `make dt_binding_check DT_SCHEMA_FILES=ads112c04`
before sending.)

> +    description: Resistance of the external resistor between REFP and REFN.
> +
> +patternProperties:
> +  "^channel@[0-9a-f]$":
> +    $ref: adc.yaml
> +    unevaluatedProperties: false
> +    properties:
> +      reg:
> +        items:
> +          - maximum: 15

This chip doesn't allow arbitrary combinations, so there
are actually only 12 possible single-channel + diff-channels
values. So maximum: 11 and channel@[0-9a-b] would make sense.

> +
> +      single-channel:
> +        maximum: 3
> +
> +      diff-channels:
> +        items:
> +          maximum: 3

For this chip, we should also have excitation-channels, excitation-current-nanoamp,
and reference-sources.

> +
> +    oneOf:
> +      - required: [ single-channel ]
> +      - required: [ diff-channels ]
> +