Re: [PATCH 3/3] ASoC: amd: fix for variable set but not used warning

[Christophe JAILLET <christophe.jaillet@wanadoo.fr>]

Le 07/07/2022 à 15:26, Vijendar Mukunda a écrit :
> Fix below kernel warning.
>>>> sound/soc/amd/acp-es8336.c:200:13: warning: variable 'ret' set but
>>>> not used [-Wunused-but-set-variable]
> 

Hi,
this patch, looks odd to me.


> Signed-off-by: Vijendar Mukunda <Vijendar.Mukunda@amd.com>
> Reported-by: kernel test robot <lkp@intel.com>
> ---
>   sound/soc/amd/acp-es8336.c | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/sound/soc/amd/acp-es8336.c b/sound/soc/amd/acp-es8336.c
> index 90f4e5809c72..e1479ae684e9 100644
> --- a/sound/soc/amd/acp-es8336.c
> +++ b/sound/soc/amd/acp-es8336.c
> @@ -206,6 +206,8 @@ static int st_es8336_late_probe(struct snd_soc_card *card)
>   		dev_err(card->dev, "can not find codec dev\n");

The next devm_acpi_dev_add_driver_gpios() will fail, should we return 
immediately?

>   
>   	ret = devm_acpi_dev_add_driver_gpios(codec_dev, acpi_es8336_gpios);
> +	if (ret)
> +		dev_warn(card->dev, "Failed to add driver gpios\n");

Should we return immediately?
>   
>   	gpio_pa = gpiod_get_optional(codec_dev, "pa-enable", GPIOD_OUT_LOW);
>   	if (IS_ERR(gpio_pa)) {
> @@ -213,6 +215,7 @@ static int st_es8336_late_probe(struct snd_soc_card *card)
>   				    "could not get pa-enable GPIO\n");
>   		gpiod_put(gpio_pa);
>   		put_device(codec_dev);
> +		return ret;

Here, we return 'ret' which is what is returned by 
devm_acpi_dev_add_driver_gpios(). So there doesn't seem to be a link 
with this block which checks for gpiod_get_optional() errors.

Moreover, returning an error for something that is optional 
(gpiod_get_optional()) looks strange.

Finally, should an error be returned, maybe PTR_ERR(gpio_pa) would be 
better here.


Just my 2c.

CJ

>   	}
>   	return 0;
>   }