Re: [PATCH v2 2/4] dt-bindings: phy: nuvoton,ma35d1-usb2-phy: extend for dual-port OTG support

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] The commit message claims multiple driver behavioral changes that are missing from the patch, leaving the driver incompatible with the new binding.
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commit f557b8622653f3df69b040020ac61c52fd0498d6
Author: Joey Lu <a0987203069@gmail.com>

dt-bindings: phy: nuvoton,ma35d1-usb2-phy: extend for dual-port OTG support

This commit updates the device tree binding for the MA35D1 USB2 PHY to support
dual-port OTG. It changes the PHY node to be a child of a syscon node, removes
the nuvoton,sys and clocks properties, and updates #phy-cells to 1.

>       - The PHY node is now a child of the system-management syscon node
>         with a reg property.  The nuvoton,sys phandle and clocks properties
>         are removed; the driver derives the regmap from its parent, and
>         clock gating is owned by each individual USB controller.
>     
>       - #phy-cells changes from 0 to 1: the cell selects the PHY port.

> diff --git a/Documentation/devicetree/bindings/phy/nuvoton,ma35d1-usb2-phy.yaml b/Documentation/devicetree/bindings/phy/nuvoton,ma35d1-usb2-phy.yaml
> index fff858c909a06..a20d03c80932b 100644
> --- a/Documentation/devicetree/bindings/phy/nuvoton,ma35d1-usb2-phy.yaml
> +++ b/Documentation/devicetree/bindings/phy/nuvoton,ma35d1-usb2-phy.yaml
[ ... ]
> @@ -8,38 +8,72 @@ title: Nuvoton MA35D1 USB2 phy
[ ... ]
>    "#phy-cells":
> -    const: 0
> +    const: 1
> +    description:
> +      The single cell selects the PHY port. 0 selects the OTG port (USB0,
> +      shared with DWC2 gadget controller) and 1 selects the host-only port
> +      (USB1).
>  
> -  clocks:
> -    maxItems: 1
>  
> -  nuvoton,sys:
> -    $ref: /schemas/types.yaml#/definitions/phandle
> +  nuvoton,rcalcode:

[Severity: High]
Does this patch introduce a regression by updating the binding without the
corresponding driver updates?

The commit message indicates the driver derives the regmap from its parent and
handles the #phy-cells change, but this patch does not contain driver
modifications.

If a device tree is updated to comply with this new binding, will the existing
driver fail to probe? Looking at ma35_usb_phy_probe() in
drivers/phy/nuvoton/phy-ma35d1-usb2.c, it unconditionally requires the
nuvoton,sys property:

drivers/phy/nuvoton/phy-ma35d1-usb2.c:ma35_usb_phy_probe() {
    ...
    p_phy->sysreg = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
                                                    "nuvoton,sys");
    if (IS_ERR(p_phy->sysreg))
        ...
}

Additionally, the unmodified driver still uses of_phy_simple_xlate and
registers a single PHY, which is structurally incompatible with the binding
change to #phy-cells = <1>:

drivers/phy/nuvoton/phy-ma35d1-usb2.c:ma35_usb_phy_probe() {
    ...
    provider = devm_of_phy_provider_register(&pdev->dev, of_phy_simple_xlate);
    ...
}

Should the driver changes be included in this patch or submitted together as
a series to avoid breaking USB initialization at boot time for compliant device
trees?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260625023958.569299-1-a0987203069@gmail.com?part=2

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