Re: [net-next,v14,3/3] net: stmmac: dwmac-nuvoton: Add dwmac glue for Nuvoton MA35 family

[Joey Lu <a0987203069@gmail.com>]

On 3/18/2026 4:23 PM, Simon Horman wrote:
> This is an AI-generated review of your patch. The human sending this
> email has considered the AI review valid, or at least plausible.
>
> For local reproduction steps see https://netdev-ai.bots.linux.dev/ai-local.html
> ---
> net: stmmac: dwmac-nuvoton: Add dwmac glue for Nuvoton MA35 family
>
> Add support for Gigabit Ethernet on Nuvoton MA35 series using dwmac
> driver.
>
>> diff --git a/drivers/net/ethernet/stmicro/stmmac/Kconfig b/drivers/net/ethernet/stmicro/stmmac/Kconfig
>> --- a/drivers/net/ethernet/stmicro/stmmac/Kconfig
>> +++ b/drivers/net/ethernet/stmicro/stmmac/Kconfig
> [ ... ]
>
>> diff --git a/drivers/net/ethernet/stmicro/stmmac/Makefile b/drivers/net/ethernet/stmicro/stmmac/Makefile
>> --- a/drivers/net/ethernet/stmicro/stmmac/Makefile
>> +++ b/drivers/net/ethernet/stmicro/stmmac/Makefile
> [ ... ]
>
>> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-nuvoton.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-nuvoton.c
>> --- /dev/null
>> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-nuvoton.c
>> @@ -0,0 +1,136 @@
> [ ... ]
>
>> +static int nvt_gmac_probe(struct platform_device *pdev)
>> +{
>> +	struct plat_stmmacenet_data *plat_dat;
>> +	struct stmmac_resources stmmac_res;
>> +	struct device *dev = &pdev->dev;
>> +	struct nvt_priv_data *priv;
>> +	int ret;
>> +
>> +	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
>> +	if (ret)
>> +		return dev_err_probe(dev, ret, "Failed to get platform resources\n");
>> +
>> +	plat_dat = devm_stmmac_probe_config_dt(pdev, stmmac_res.mac);
>> +	if (IS_ERR(plat_dat))
>> +		return dev_err_probe(dev, PTR_ERR(plat_dat), "Failed to get platform data\n");
>> +
>> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
>> +	if (!priv)
>> +		return dev_err_probe(dev, -ENOMEM, "Failed to allocate private data\n");
>> +
>> +	priv->regmap = syscon_regmap_lookup_by_phandle_args(dev->of_node, "nuvoton,sys",
>> +							    1, &priv->macid);
>> +	if (IS_ERR(priv->regmap))
>> +		ret = dev_err_probe(dev, PTR_ERR(priv->regmap), "Failed to get sys register\n");
>> +
>> +	if (priv->macid > 1)
>> +		ret = dev_err_probe(dev, -EINVAL, "Invalid sys arguments\n");
>>                                                                                    ^^^^
> Does this code return the error on failure? The dev_err_probe() result is
> assigned to ret but the function continues execution without returning.
>
> Russell King's v12 review suggested using set_phy_intf_sel callback,
> which led to significant refactoring in v12. This refactoring appears to
> have inadvertently broken the error handling here and below.
>
> The code should be:
> 	if (IS_ERR(priv->regmap))
> 		return dev_err_probe(dev, PTR_ERR(priv->regmap), "Failed to get sys register\n");
>
> 	if (priv->macid > 1)
> 		return dev_err_probe(dev, -EINVAL, "Invalid sys arguments\n");
>
> See Russell's v12 review:
> https://lore.kernel.org/netdev/aYsurPBMnzWDZCco@shell.armlinux.org.uk/

Sorry for missing that, I'll fix it so that function properly returns 
failure.

Joey

>
>> +
>> +	plat_dat->bsp_priv = priv;
>> +	plat_dat->set_phy_intf_sel = nvt_set_phy_intf_sel;
>> +
>> +	return stmmac_pltfr_probe(pdev, plat_dat, &stmmac_res);
>> +}
> [ ... ]