Re: [PATCH v2 03/10] dt-bindings: ptp: Document TSCSS hardware on Qualcomm Nord and Shikra SoCs

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential
issues to consider:
- [Low] dt-bindings: ptp: qcom,nord-tscss: missing reg constraints in
  allOf
- [Low] dt-bindings: ptp: qcom,nord-tscss: invalid fallback and variant
  split
--

commit cdeb0d9b5fccebd2b2b765c9fc60dd95752de832
Author: Imran Shaik <imran.shaik@oss.qualcomm.com>

dt-bindings: ptp: Document TSCSS hardware on Qualcomm Nord and Shikra SoCs

This commit adds the devicetree binding schema for the Timestamp Counter
Subsystem (TSCSS) on Qualcomm Nord and Shikra SoCs.

> diff --git a/Documentation/devicetree/bindings/ptp/qcom,nord-tscss.yaml b/Documentation/devicetree/bindings/ptp/qcom,nord-tscss.yaml
> new file mode 100644
> index 0000000000000..9d49e66a35c98
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/ptp/qcom,nord-tscss.yaml

[ ... ]

> +properties:
> +  compatible:
> +    oneOf:
> +      - const: qcom,nord-tscss
> +      - items:
> +          - const: qcom,shikra-tscss
> +          - const: qcom,nord-tscss
> +
> +  reg:
> +    minItems: 1
> +    maxItems: 3
> +
> +  reg-names:
> +    minItems: 1
> +    items:
> +      - const: tsc
> +      - const: etu
> +      - const: timer

[ ... ]

> +allOf:
> +  - if:
> +      properties:
> +        reg-names:
> +          contains:
> +            const: etu
> +    then:
> +      required:
> +        - interrupts
> +        - interrupt-names
> +        - pinctrl-names
> +        - qcom,etu-slice
> +        - qcom,etu-event-sel
> +
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: qcom,shikra-tscss
> +    then:
> +      properties:
> +        reg-names:
> +          minItems: 1
> +          items:
> +            - const: tsc
> +            - const: etu
> +        pinctrl-names:
> +          maxItems: 8
> +        qcom,etu-slice:
> +          maxItems: 8
> +        qcom,etu-event-sel:
> +          maxItems: 8

[Severity: Low]
Should these allOf conditionals also constrain reg to match reg-names?

When reg-names contains etu, reg is not given minItems: 2, so a node with
a single reg entry still passes validation.  Similarly, the
qcom,shikra-tscss branch restricts reg-names to tsc and etu without
setting maxItems: 2 on reg (and redefines the items list instead of setting
maxItems: 2 on reg-names), allowing 3 reg entries on Shikra.

[Severity: Low]
Is qcom,nord-tscss a valid fallback compatible for qcom,shikra-tscss?

Nord has a timer register region and up to 32 ETU slices, whereas Shikra
lacks the timer region and only supports 8 slices, so a Shikra device is a
subset rather than backwards-compatible with Nord.  Combining them also
requires per-compatible overrides for reg-names, pinctrl-names,
qcom,etu-slice, and qcom,etu-event-sel; should qcom,shikra-tscss be split
or grouped with a matching 2-region TSCSS schema instead of falling back to
qcom,nord-tscss?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261108-tscss-v2-0-d5f575010427@oss.qualcomm.com?part=3