Re: [PATCH v2 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 a1eb87e2fab2443f5d8889e3755038df391d4632
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 into qcom_pcie_probe()
to share it between mixed and legacy platforms. This prevents -EBUSY errors
when acquiring the PERST# GPIO in legacy cases.

Link: 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 leak the runtime PM usage count?

Earlier in qcom_pcie_probe(), pm_runtime_get_sync() is called to increment
the PM usage count. If devm_gpiod_get_optional() fails here, returning
directly bypasses the err_pm_runtime_put cleanup path, which leaves runtime
PM enabled and causes an unbalanced count.

Should this be setting ret = PTR_ERR(pcie->reset) and jumping to
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/20260608-sm8350-wifi-v2-0-efb68f1ff04c@oss.qualcomm.com?part=1