Thank you for your contribution! Sashiko AI review found 3 potential issue(s) 
to consider:
- [High] PM Runtime on the parent device is enabled after the PHY device is 
created, preventing PM runtime from propagating to the parent and causing 
unpowered hardware accesses.
- [Medium] The DP PHY driver fails to parse and apply the `nvmem-cells` 
calibration data specified in the new device tree binding.
- [Low] The variable `ret` is used but not declared in `mtk_dp_phy_probe()`, 
causing a build failure.
--

--- Patch [3]: [PATCH v2 03/12] phy: phy-mtk-dp: Allow probing with devicetree 
match ---
commit e7cb0174c7cb05364cf12874f491ce4c799f2c61
Author: AngeloGioacchino Del Regno <[email protected]>

phy: phy-mtk-dp: Allow probing with devicetree match

This commit adds a devicetree match to decouple the MediaTek DP PHY driver
from the DisplayPort IP driver. It implements a standalone probe path while
retaining a legacy probe function for backwards compatibility.

> diff --git a/drivers/phy/mediatek/phy-mtk-dp.c 
> b/drivers/phy/mediatek/phy-mtk-dp.c
> --- a/drivers/phy/mediatek/phy-mtk-dp.c
> +++ b/drivers/phy/mediatek/phy-mtk-dp.c

[ ... ]

> @@ -160,43 +161,106 @@ static const struct phy_ops mtk_dp_phy_dev_ops = {

[ ... ]

>  static int mtk_dp_phy_probe(struct platform_device *pdev)
>  {
>       struct device *dev = &pdev->dev;
> +     struct phy_provider *provider;
>       struct mtk_dp_phy *dp_phy;
> +     void __iomem *base;
>       struct phy *phy;
> -     struct regmap *regs;
> -
> -     regs = *(struct regmap **)dev->platform_data;
> -     if (!regs)
> -             return dev_err_probe(dev, -EINVAL,
> -                                  "No data passed, requires struct 
> regmap**\n");
>  
>       dp_phy = devm_kzalloc(dev, sizeof(*dp_phy), GFP_KERNEL);
>       if (!dp_phy)
>               return -ENOMEM;
>  
> -     dp_phy->regmap = regs;
> +     dp_phy->dev = dev;
> +
> +     /* If there's no devicetree, go for legacy pdev probe */
> +     if (!dev->of_node)
> +             return mtk_dp_phy_legacy_probe(pdev, dp_phy);

[Severity: Medium]
Does the new devicetree probe path need to parse and apply the nvmem-cells
calibration data?

It looks like the new DT bindings specify nvmem-cells for optimal EYE signal
pattern calibration, but the standalone probe path doesn't retrieve them,
which might leave the hardware running with sub-optimal defaults.

> +
> +     base = devm_platform_ioremap_resource(pdev, 0);
> +     if (IS_ERR(base))
> +             return PTR_ERR(base);
> +
> +     dp_phy->regmap = devm_regmap_init_mmio(dev, base, 
> &mtk_dp_phy_regmap_cfg);
> +     if (IS_ERR(dp_phy->regmap))
> +             return PTR_ERR(dp_phy->regmap);
> +
>       phy = devm_phy_create(dev, NULL, &mtk_dp_phy_dev_ops);

[Severity: High]
Will creating the PHY device before enabling PM runtime on the parent
prevent the PHY framework from propagating PM runtime to the child PHY
device?

In phy_create(), the framework checks pm_runtime_enabled(dev) on the parent
to decide whether to enable PM runtime on the newly created PHY device. Since
devm_pm_runtime_enable(dev) is called later, this check evaluates to false.

Could this lead to phy_pm_runtime_get_sync() returning -ENOTSUPP and
bypassing hardware wake-ups, resulting in unpowered register accesses?

>       if (IS_ERR(phy))
>               return dev_err_probe(dev, PTR_ERR(phy),
>                                    "Failed to create DP PHY\n");
>  
>       phy_set_drvdata(phy, dp_phy);
> -     if (!dev->of_node)
> -             phy_create_lookup(phy, "dp", dev_name(dev));
> +
> +     provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
> +     if (IS_ERR(provider))
> +             return PTR_ERR(provider);
> +
> +     ret = devm_pm_runtime_enable(dev);
> +     if (ret)
> +             return ret;

[Severity: Low]
Is the variable ret missing a declaration here?

It appears int ret; is not declared in mtk_dp_phy_probe(), which will cause
a build failure when compiling the driver.

>  
>       return 0;
>  }

-- 
Sashiko AI review ยท 
https://sashiko.dev/#/patchset/[email protected]?part=3

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