Re: [PATCH 1/4] 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] Driver/Schema Mismatch: Driver unconditionally requests 'vdd' regulator while schema removes it for MSM8996
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commit 3e28a2c0425272ba6818b0dca5f1d04b00a00662
Author: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>

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

This commit adds a specific compatible string for SM6125 with an SM6115
fallback. It also updates the MSM8996 bindings to require power domains
and operating performance points instead of a vdd-supply.

> diff --git a/Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml b/Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml
> index 39851ba9de436..807d64aee547c 100644
> --- a/Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml
> +++ b/Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml

[ ... ]

> @@ -182,6 +190,22 @@ 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
> +    else:
> +      properties:
> +        power-domains: false
> +        required-opps: false
> +      required:
> +        - vdd-supply

[ ... ]

> @@ -196,10 +220,13 @@ examples:
>                   <&gcc GCC_RX1_USB2_CLKREF_CLK>;
>          clock-names = "cfg_ahb", "ref";
>  
> -        vdd-supply = <&pm8994_l28>;

[Severity: Medium]
Does this removal of vdd-supply for MSM8996 create a mismatch with the
existing qusb2 driver?

Looking at qusb2_phy_probe() in drivers/phy/qualcomm/phy-qcom-qusb2.c, the
driver unconditionally requests all regulators defined in
qusb2_phy_vreg_names, which includes the vdd supply:

drivers/phy/qualcomm/phy-qcom-qusb2.c:qusb2_phy_probe()
    num = ARRAY_SIZE(qphy->vregs);
    for (i = 0; i < num; i++)
        qphy->vregs[i].supply = qusb2_phy_vreg_names[i];

    ret = devm_regulator_bulk_get(dev, num, qphy->vregs);

If a device tree omits vdd-supply to follow this new schema intent, will
the driver fail to probe with -ENODEV or log an unwanted warning when
falling back to a dummy regulator? 

Should the driver be updated to handle the vdd regulator as optional for
hardware variants that use power domains?

>          vdda-pll-supply = <&pm8994_l12>;
>          vdda-phy-dpdm-supply = <&pm8994_l24>;

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260610-topic-8996_61x5_qusb2phy-v1-0-d7135980e78f@oss.qualcomm.com?part=1

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