Re: [PATCH v9 33/36] pinctrl: airoha: try to find chip scu node by phandle first

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] The fallback logic for chip SCU regmap lookup masks `-EPROBE_DEFER` and other legitimate errors from `syscon_regmap_lookup_by_phandle()`.
--

--- Patch [33]: [PATCH v9 33/36] pinctrl: airoha: try to find chip scu node by phandle first ---
commit 61237bb0bf7e8867822c8f795d7f2be68c677edc
Author: Mikhail Kshevetskiy <[email protected]>

pinctrl: airoha: try to find chip scu node by phandle first
    
The patch updates the airoha pinctrl driver to first search for the chip
SCU regmap using the "airoha,chip-scu" phandle. If that fails, it falls
back to using the SoC-specific compatible string.

> diff --git a/drivers/pinctrl/airoha/pinctrl-airoha.c b/drivers/pinctrl/airoha/pinctrl-airoha.c
> index 5a9afea4bb960..f6acbfdd0911f 100644
> --- a/drivers/pinctrl/airoha/pinctrl-airoha.c
> +++ b/drivers/pinctrl/airoha/pinctrl-airoha.c

[ ... ]

> @@ -781,9 +781,12 @@ int airoha_pinctrl_probe(struct platform_device *pdev)
>  	if (IS_ERR(pinctrl->regmap))
>  		return PTR_ERR(pinctrl->regmap);
>  
> -	map = syscon_regmap_lookup_by_compatible("airoha,en7581-chip-scu");
> -	if (IS_ERR(map))
> -		return PTR_ERR(map);
> +	map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "airoha,chip-scu");
> +	if (IS_ERR_OR_NULL(map)) {

[Severity: High]
Does this fallback logic inadvertently mask legitimate errors like -EPROBE_DEFER
from syscon_regmap_lookup_by_phandle()?

If the initial phandle lookup returns -EPROBE_DEFER (for instance, if the
syscon node exists but hasn't probed yet), IS_ERR_OR_NULL(map) will catch it
and execute the fallback to syscon_regmap_lookup_by_compatible().

If the legacy compatible string is then missing from the modern device tree,
the fallback will return -ENODEV. This overwrites the original -EPROBE_DEFER
error, causing the driver probe to permanently fail instead of correctly
deferring.

> +		map = syscon_regmap_lookup_by_compatible(data->chip_scu_compatible);
> +		if (IS_ERR(map))
> +			return PTR_ERR(map);
> +	}
>  
>  	pinctrl->chip_scu = map;
>

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/[email protected]?part=33