Re: [PATCH v2] dt-bindings: iio: adc: Add dt binding to xlnx,xadc

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] dt-bindings: iio: conflicting constraints when xlnx,external-mux is omitted
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commit 650a4d99eb23987562466c53ef3d4d648db29eba
Author: Omer PALA <palaomer100@gmail.com>

dt-bindings: iio: adc: Add dt binding to xlnx,xadc

Add yaml devicetree binding for xlnx,zynq-xadc-1.00.a,
xlnx,axi-xadc-1.00.a and xlnx,system-management-wiz-1.3 from
xilinx-xadc.txt file.

> diff --git a/Documentation/devicetree/bindings/iio/adc/xlnx,xadc.yaml b/Documentation/devicetree/bindings/iio/adc/xlnx,xadc.yaml
> new file mode 100644
> index 0000000000000..f9b717c297158
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/xlnx,xadc.yaml

[ ... ]

> +allOf:
> +  - if:
> +      properties:
> +        xlnx,external-mux:
> +          const: none
> +    then:
> +      properties:
> +        xlnx,external-mux-channel: false
> +
> +  - if:
> +      properties:
> +        xlnx,external-mux:
> +          const: single

[Severity: Low]
Is there a potential conflict here if the xlnx,external-mux property is
omitted?

Looking at JSON schema semantics, missing properties evaluate to true when
checked against a const. Because the if block doesn't specify
required: [xlnx,external-mux], all three of the conditional branches (none,
single, and dual) might trigger simultaneously if a valid device tree
omits the property.

> +    then:
> +      properties:
> +        xlnx,external-mux-channel:
> +          minimum: 0
> +          maximum: 16
> +      required:
> +        - xlnx,external-mux-channel

[Severity: Low]
When the xlnx,external-mux property is omitted, will this 'then' block
trigger alongside the 'none' block?

If both trigger, this block explicitly requires xlnx,external-mux-channel
while the 'none' block simultaneously forbids it. This could cause valid
device trees that rely on the default value to fail dtbs_check validation.

Should these 'if' blocks include a required list for the xlnx,external-mux
property to prevent them from evaluating to true when the property is
missing?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260918174809.17502-1-palaomer100@gmail.com?part=1