Re: [PATCH] ASoC: loongson: mark OF related data as maybe unused

From: Xi Ruoyao
Date: Wed Jul 26 2023 - 03:24:05 EST


On Wed, 2023-07-26 at 15:06 +0800, YingKun Meng wrote:
> The ASoC Sound Card driver can be compile tested with !CONFIG_OF
> making 'loongson_asoc_dt_ids' unused:
>
> sound/soc/loongson/loongson_card.c:200:34: warning: unused variable
> 'loongson_asoc_dt_ids' [-Wunused-const-variable]

Hmm, why not guard the definition with #ifdef CONFIG_OF instead?

Source text is first and foremost for the human reader, not for the
compiler, and an ifdef clearly shows the condition when the definition
is not used.

> Here we solve it in the same way as [1].
>
> [1] https://lore.kernel.org/all/20201125164452.89239-1-krzk@xxxxxxxxxx/
>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Closes: https://lore.kernel.org/oe-kbuild-all/202307242008.xqdjgk04-lkp@xxxxxxxxx
> Fixes: d24028606e76 ("ASoC: loongson: Add Loongson ASoC Sound Card Support")
> Signed-off-by: YingKun Meng <mengyingkun@xxxxxxxxxxx>
> ---
>  sound/soc/loongson/loongson_card.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/sound/soc/loongson/loongson_card.c b/sound/soc/loongson/loongson_card.c
> index 9ded16329747..7dd7adc13484 100644
> --- a/sound/soc/loongson/loongson_card.c
> +++ b/sound/soc/loongson/loongson_card.c
> @@ -197,7 +197,7 @@ static int loongson_asoc_card_probe(struct platform_device *pdev)
>         return ret;
>  }
>  
> -static const struct of_device_id loongson_asoc_dt_ids[] = {
> +static const struct of_device_id loongson_asoc_dt_ids[] __maybe_unused = {
>         { .compatible = "loongson,ls-audio-card" },
>         { /* sentinel */ },
>  };

--
Xi Ruoyao <xry111@xxxxxxxxxxx>
School of Aerospace Science and Technology, Xidian University