Re: [PATCH 1/3] dt-bindings: regulator: Add RPMI voltage service bindings

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] dt-bindings: non-standard voltage-domains property bypasses regulator core
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commit f9ded6ad4ad8d417c9182647856a155cfddbfb6d
Author: Joshua Yeong <joshua.yeong@starfivetech.com>

dt-bindings: regulator: Add RPMI voltage service bindings
    
This commit adds device tree bindings for the RISC-V Platform Management
Interface (RPMI) voltage service group. It defines the bindings for both the
supervisor-facing regulator controller and the SBI MPXY channel used to
expose the service group.

> diff --git a/Documentation/devicetree/bindings/regulator/riscv,rpmi-voltage.yaml b/Documentation/devicetree/bindings/regulator/riscv,rpmi-voltage.yaml
> new file mode 100644
> index 0000000000000..66d1c26592c16
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/regulator/riscv,rpmi-voltage.yaml

[ ... ]

> +properties:
> +  compatible:
> +    description:
> +      Intended for use by the supervisor software.
> +    const: riscv,rpmi-voltage
> +
> +  mboxes:
> +    maxItems: 1
> +    description:
> +      Mailbox channel of the underlying RPMI transport or SBI message proxy channel.
> +
> +  "#voltage-domain-cells":
> +    const: 1
> +    description:
> +      Lets a consumer name a domain by its RPMI DOMAIN_ID, the single cell of
> +      a "voltage-domains" entry, without a child node for the domain.

[Severity: High]
Does this non-standard provider cell count bypass the standard regulator core
linkage? By using a custom voltage-domains property instead of the standard
<name>-supply pattern, consumers using this linkage will globally fail
dt_binding_check validation since voltage-domains is unrecognized by
devicetree core schemas or standard consumer schemas.

[ ... ]

> +    codec {
> +        compatible = "vendor,codec";
> +        vdd-supply = <&volt2_reg>;
> +    };
> +
> +    // Domains 3 and 4 by DOMAIN_ID, with no child node for either.
> +    phy {
> +        compatible = "vendor,phy";
> +        voltage-domains = <&rpmi_voltage 3>, <&rpmi_voltage 4>;
> +        voltage-domain-names = "vdda", "vddio";
> +    };
> +...

[Severity: High]
Will this custom linkage break driver core probe ordering?

Since the driver core (fw_devlink) cannot track voltage-domains dependencies,
it has no way of knowing this property names a supplier. If cell-based
dynamic regulator mapping without subnodes is required, shouldn't it be
introduced globally (e.g., #regulator-cells in regulator.yaml) and approved
by the core devicetree and regulator maintainers rather than using a
platform-specific model here?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260922161156.1088153-1-joshua.yeong@starfivetech.com?part=1