Re: [PATCH V2] PCI: tegra194: Fix probe path for Endpoint mode

[Manivannan Sadhasivam <mani@xxxxxxxxxx>]

On Mon, Apr 08, 2024 at 03:00:53PM +0530, Vidya Sagar wrote:
> Tegra194 PCIe probe path is taking failure path in success case for
> Endpoint mode. Return success from the switch case instead of going
> into the failure path.
> 
> Fixes: c57247f940e8 ("PCI: tegra: Add support for PCIe endpoint mode in Tegra194")
> Signed-off-by: Vidya Sagar <vidyas@xxxxxxxxxx>
> Reviewed-by: Jon Hunter <jonathanh@xxxxxxxxxx>
> ---
> v2:
> * Added 'Fixes' and 'Reviewed-by' from Jon Hunter
> 
>  drivers/pci/controller/dwc/pcie-tegra194.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
> index 4bba31502ce1..1a8178dc899a 100644
> --- a/drivers/pci/controller/dwc/pcie-tegra194.c
> +++ b/drivers/pci/controller/dwc/pcie-tegra194.c
> @@ -2273,11 +2273,14 @@ static int tegra_pcie_dw_probe(struct platform_device *pdev)
>  		ret = tegra_pcie_config_ep(pcie, pdev);
>  		if (ret < 0)
>  			goto fail;
> +		else
> +			return 0;

This pattern is prone to error just like how it was before this patch. You
should just return 0 at the end of the function for success case and direct all
failure cases to 'fail' label:

```
diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index 1f7b662cb8e1..f410aae0ee7f 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -2236,9 +2236,8 @@ static int tegra_pcie_dw_probe(struct platform_device *pdev)
        pcie->icc_path = devm_of_icc_get(&pdev->dev, "write");
        ret = PTR_ERR_OR_ZERO(pcie->icc_path);
        if (ret) {
-               tegra_bpmp_put(pcie->bpmp);
                dev_err_probe(&pdev->dev, ret, "failed to get write interconnect\n");
-               return ret;
+               goto fail;
        }
 
        switch (pcie->of_data->mode) {
@@ -2254,8 +2253,6 @@ static int tegra_pcie_dw_probe(struct platform_device *pdev)
                ret = tegra_pcie_config_rp(pcie);
                if (ret && ret != -ENOMEDIUM)
                        goto fail;
-               else
-                       return 0;
                break;
 
        case DW_PCIE_EP_TYPE:
@@ -2278,8 +2275,11 @@ static int tegra_pcie_dw_probe(struct platform_device *pdev)
        default:
                dev_err(dev, "Invalid PCIe device type %d\n",
                        pcie->of_data->mode);
+               goto fail;
        }
 
+       return 0;
+
 fail:
        tegra_bpmp_put(pcie->bpmp);
        return ret;
```

- Mani

-- 
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