Re: [PATCH net-next v2 04/12] dt-bindings: net: dsa: renesas,rzn1-a5psw: Add RZ/T2H and RZ/N2H ETHSW support

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Medium] dt-bindings: net: dsa: a5psw: globally requiring interrupts breaks backward ABI
- [Low] dt-bindings: net: dsa: a5psw: missing port count restriction for ETHSW variant
--

commit ac61e34c73e390592b92437f35f98d8807997f55
Author: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

dt-bindings: net: dsa: renesas,rzn1-a5psw: Add RZ/T2H and RZ/N2H ETHSW support

This commit extends the A5PSW DSA binding to cover the ETHSW variant used on
newer Renesas SoCs. It updates the schema with new compatible strings, modifies
interrupt and clock properties, and accounts for the 4-port topology.

> diff --git a/Documentation/devicetree/bindings/net/dsa/renesas,rzn1-a5psw.yaml b/Documentation/devicetree/bindings/net/dsa/renesas,rzn1-a5psw.yaml
> index fab6aa6237e93..863633185912f 100644
> --- a/Documentation/devicetree/bindings/net/dsa/renesas,rzn1-a5psw.yaml
> +++ b/Documentation/devicetree/bindings/net/dsa/renesas,rzn1-a5psw.yaml
[ ... ]
> @@ -73,14 +145,48 @@ properties:
>                phandle pointing to a PCS sub-node compatible with
>                renesas,rzn1-miic.yaml#
>  
> -unevaluatedProperties: false
> -
>  required:
>    - compatible
>    - reg
>    - clocks
>    - clock-names
>    - power-domains
> +  - interrupts
> +  - interrupt-names

[Severity: Medium]
Does adding interrupts and interrupt-names to the top-level required array
cause a regression by breaking backward compatibility for legacy device trees?

Existing device trees for the older renesas,rzn1-a5psw hardware that do not
specify the interrupts property will now fail validation. Since the Linux
driver does not currently utilize interrupts, it is perfectly valid and
functional for older device trees to omit them.

Should these properties only be required conditionally within the then block
for the new hardware variant?

> +
> +allOf:
> +  - $ref: dsa.yaml#/$defs/ethernet-ports
> +
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: renesas,r9a09g077-ethsw
> +    then:
> +      properties:
> +        interrupts:
> +          minItems: 24
> +        interrupt-names:
> +          minItems: 24
> +        clocks:
> +          minItems: 3
> +        clock-names:
> +          minItems: 3
> +      required:
> +        - resets

[Severity: Low]
Does this conditional block need to restrict the port count for the new
ETHSW variant?

The global patternProperties for ethernet-ports allows
"^(ethernet-)?port@[0-4]$", which globally permits up to 5 ports. This is
correct for the older A5PSW variant but incorrect for the new 4-port ETHSW
variant.

Without a port count restriction here (e.g., overriding and disabling port@4),
device trees with invalid 5-port configurations for the new variant will
silently pass schema validation.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261001154326.754314-1-prabhakar.mahadev-lad.rj@bp.renesas.com?part=4