Re: [PATCH v2 1/5] dt-bindings: phy: qcom,qusb2: Straighten out SM6125 and MSM8996

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] The binding change causes dtbs_check to fail for existing in-tree MSM8996 and SM6125 device trees, and introduces an architectural disconnect with the driver's unconditional regulator requests.
--

commit a8357f1a883ddad429bf80e6c26f5fba143404de
Author: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>

dt-bindings: phy: qcom,qusb2: Straighten out SM6125 and MSM8996

SM6125 DT currently uses just the MSM8996 compatible (without a primary
SM6125-specific one). This commit adds a new compatible for SM6125 with
a SM6115 fallback. It also updates the MSM8996 binding to require
power-domains and required-opps instead of vdd-supply.

> diff --git a/Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml b/Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml
> index 001fd0ccc9852..cfc5a1d16b7f2 100644
> --- a/Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml
> +++ b/Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml
[ ... ]
> @@ -187,6 +195,22 @@ allOf:
>          qcom,preemphasis-width: false
>          qcom,hsdisc-trim-value: false
>  
> +  # On MSM8996, VDD is supplied via the MX power domain
> +  - if:
> +      properties:
> +        compatible:
> +          const: qcom,msm8996-qusb2-phy
> +    then:
> +      required:
> +        - power-domains
> +        - required-opps

[Severity: Medium]
Will this break dtbs_check for existing in-tree MSM8996 and SM6125 device
trees by mandating power-domains for MSM8996 before the in-tree device
trees are updated?

While this dtbs_check breakage is resolved later in the series by commit
"arm64: dts: qcom: msm8996: Add VDD_MX to QUSB2 PHYs" and commit
"arm64: dts: qcom: sm6125: Fix QUSB2 compatible", does this change create
an architectural disconnect with the driver that remains unresolved?

Looking at drivers/phy/qualcomm/phy-qcom-qusb2.c, it unconditionally
requires the vdd regulator:

drivers/phy/qualcomm/phy-qcom-qusb2.c:qusb2_phy_vreg_names[] = {
        "vdd", "vdda-pll", "vdda-phy-dpdm",
};

If a strictly schema-compliant device tree omits vdd-supply for MSM8996,
would this cause the driver to fail probing when it unconditionally fetches
vdd via devm_regulator_bulk_get()?

> +    else:
> +      properties:
> +        power-domains: false
> +        required-opps: false
> +      required:
> +        - vdd-supply

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260903-topic-8996_61x5_qusb2phy-v2-0-4c3f980a4560@oss.qualcomm.com?part=1

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