Re: [PATCH v6 4/5] dt-bindings: iio: dac: Add AD5529R

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Medium] Missing `spi-cpha` and `spi-cpol` in the `properties` block causes valid SPI Mode 3 configurations to fail dt-schema validation.
- [Medium] Using `additionalProperties: false` with `$ref: dac.yaml` breaks inheritance, causing standard DAC properties to be incorrectly rejected.
--

--- Patch [4]: [PATCH v6 4/5] dt-bindings: iio: dac: Add AD5529R ---
commit e027ded7c4d70f1636e16dc892937b3656b0c91d
Author: Janani Sunil <janani.sunil@analog.com>

dt-bindings: iio: dac: Add AD5529R

Devicetree bindings for AD5529R 16 channel 12/16 bit high voltage,
buffered voltage output digital-to-analog converter (DAC) with an
integrated precision reference.

> diff --git a/Documentation/devicetree/bindings/iio/dac/adi,ad5529r.yaml b/Documentation/devicetree/bindings/iio/dac/adi,ad5529r.yaml
> new file mode 100644
> index 0000000000000..730206fd6eaba
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/dac/adi,ad5529r.yaml
> @@ -0,0 +1,224 @@

[ ... ]

> +patternProperties:
> +  "^channel@([0-9a-f]{1,2})$":
> +    $ref: dac.yaml
> +    type: object
> +    description: Child nodes for individual channel configuration
> +
> +    properties:
> +      reg:
> +        description:
> +          Flattened channel number across all AD5529R devices sharing the chip
> +          select. Within each 16-channel block, the physical channel number is reg % 16.
> +        minimum: 0
> +        maximum: 63
> +
> +      output-range-microvolt:

[ ... ]

> +    required:
> +      - reg
> +
> +    additionalProperties: false

[Severity: Medium]
Since this node uses $ref: dac.yaml, shouldn't this be
unevaluatedProperties: false instead?

Using additionalProperties: false restricts valid properties strictly to the
local properties block. Standard DAC properties inherited from dac.yaml
(such as label) will be incorrectly rejected by dt_binding_check.

> +
> +required:
> +  - compatible
> +  - reg
> +  - vdd-supply
> +  - avdd-supply
> +  - hvdd-supply
> +
> +dependencies:
> +  spi-cpha: [ spi-cpol ]
> +  spi-cpol: [ spi-cpha ]

[Severity: Medium]
Will this fail dt_binding_check validation for valid SPI Mode 3
configurations?

The dependencies block enforces that both properties are present, but spi-cpha
and spi-cpol are not explicitly defined in the properties block.

Because unevaluatedProperties: false is used at the top level and
spi-peripheral-props.yaml does not define spi-cpha or spi-cpol, they must be
explicitly declared (e.g., spi-cpha: true) in the properties block.

Otherwise, configurations correctly using SPI Mode 3 will be rejected with an
"unevaluated property" error.

> +
> +allOf:
> +  - $ref: /schemas/spi/spi-peripheral-props.yaml#
> +
> +unevaluatedProperties: false

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260715-ad5529r-driver-v6-0-cfdf8b9f5ee3@analog.com?part=4