Re: [PATCH 1/7] PCI: qcom: fix parsing of PERST# in the legacy case

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] Direct return on devm_gpiod_get_optional failure in qcom_pcie_probe() bypasses PM runtime cleanup.
--

commit 40b8aa014962b990fbbdd6f190bcea40db01e096
Author: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

PCI: qcom: fix parsing of PERST# in the legacy case

This commit moves the parsing of the RC's perst-gpios to qcom_pcie_probe()
to handle both mixed and legacy device tree configurations without acquiring
the same GPIO twice.

Closes: https://lore.kernel.org/r/gieaybsg2ckxpctvqj77nlwu7utama2yeyvebkonmexsxrra3v@v3fobqasxnmy/

> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index 11fc604898926..7664c7c28c0e3 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c

[ ... ]

> @@ -2107,6 +2093,15 @@ static int qcom_pcie_probe(struct platform_device *pdev)
>  
>  	pp->ops = &qcom_pcie_dw_ops;
>  
> +	if (of_find_property(dev->of_node, "perst-gpios", NULL)) {
> +		pcie->reset = devm_gpiod_get_optional(dev, "perst",
> +						      GPIOD_OUT_HIGH);
> +		if (IS_ERR(pcie->reset))
> +			return PTR_ERR(pcie->reset);

[Severity: High]
Does this direct return bypass the PM runtime cleanup?

Earlier in qcom_pcie_probe(), pm_runtime_enable(dev) and
pm_runtime_get_sync(dev) are called successfully, which increments the
device's PM runtime usage counter.

If devm_gpiod_get_optional() fails here (for example, with -EPROBE_DEFER
if the GPIOs are not yet ready), returning directly leaves the PM runtime
usage counter leaked because the goto err_pm_runtime_put path is skipped.
This will lead to an unbalanced pm_runtime_enable warning during probe
retries.

Should this be updated to assign the error to ret and use goto
err_pm_runtime_put instead?

> +
> +		dev_warn(dev, "Reusing PERST# from Root Complex node. DT needs to be updated!\n");
> +	}
> +
>  	ret = qcom_pcie_parse_ports(pcie);
>  	if (ret) {
>  		if (ret != -ENODEV) {

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260601-sm8350-wifi-v1-0-242917d88031@oss.qualcomm.com?part=1