Re: [PATCH v17 2/5] phy: core: Add phy_get_by_of_node()

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] phy_get_by_of_node() misses the legacy usb-nop-xceiv workaround, causing infinite -EPROBE_DEFER loops.
--

commit a021b561c8a9bfb36addca720d49ea935b34a131
Author: Bryan O'Donoghue <bryan.odonoghue@linaro.org>

phy: core: Add phy_get_by_of_node()

This commit introduces phy_get_by_of_node() to allow looking up a phy 
directly by its device node. It refactors the existing lookup logic in 
_of_phy_get() into a new shared helper function called 
_of_phy_get_with_args().

> diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
> index 89addd732bff3..490a7cde6d40a 100644
> --- a/drivers/phy/phy-core.c
> +++ b/drivers/phy/phy-core.c
[ ... ]
> @@ -1001,6 +1015,41 @@ struct phy *devm_of_phy_get_by_index(struct device *dev, struct device_node *np,
>  }
>  EXPORT_SYMBOL_GPL(devm_of_phy_get_by_index);
>  
> +/**
> + * phy_get_by_of_node() - lookup and obtain a reference to a phy by device_node
> + * @np: node containing the phy
> + *
> + * Returns the phy associated with the device node or ERR_PTR.
> + */
> +struct phy *phy_get_by_of_node(struct device_node *np)
> +{
> +	struct of_phandle_args args = { .np = np, .args_count = 0 };
> +	struct phy *phy;
> +
> +	if (!np)
> +		return ERR_PTR(-EINVAL);
> +
> +	mutex_lock(&phy_provider_mutex);
> +
> +	phy = _of_phy_get_with_args(&args);

[Severity: Medium]
Does this new API miss the legacy compatibility check for usb-nop-xceiv?

In _of_phy_get(), there is a workaround that returns -ENODEV if the
device is compatible with "usb-nop-xceiv". Because this workaround was
left in _of_phy_get() rather than being relocated into the shared
_of_phy_get_with_args() helper, phy_get_by_of_node() bypasses it
completely.

Could this cause drivers looking up a "usb-nop-xceiv" node via this new
API to receive -EPROBE_DEFER instead of -ENODEV, leading to infinite
probe deferrals and breaking fallback to the usb-phy subsystem?

> +
> +	if (IS_ERR(phy))
> +		goto out_unlock;
> +
> +	if (!try_module_get(phy->ops->owner)) {
> +		phy = ERR_PTR(-EPROBE_DEFER);
> +		goto out_unlock;
> +	}
> +
> +	get_device(&phy->dev);
> +
> +out_unlock:
> +	mutex_unlock(&phy_provider_mutex);
> +
> +	return phy;
> +}
> +EXPORT_SYMBOL_GPL(phy_get_by_of_node);

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260906-b4-linux-next-25-03-13-dtsi-x1e80100-camss-v17-0-e2197a3e2551@linaro.org?part=2