Re: [PATCH v2 1/2] ASoC: meson: aiu: fix function pointer type mismatch

[Justin Stitt]

Hi,

On Tue, Feb 13, 2024 at 10:58:03PM +0100, Jerome Brunet wrote:
> clang-16 warns about casting functions to incompatible types, as is done
> here to call clk_disable_unprepare:
>
> sound/soc/meson/aiu.c:243:12: error: cast from 'void (*)(struct clk *)' to 'void (*)(void *)' converts to incompatible function type [-Werror,-Wcast-function-type-strict]
>   243 |                                        (void(*)(void *))clk_disable_unprepare,
>
> The pattern of getting, enabling and setting a disable callback for a
> clock can be replaced with devm_clk_get_enabled(), which also fixes
> this warning.
>
> Fixes: 6ae9ca9ce986 ("ASoC: meson: aiu: add i2s and spdif support")
> Reported-by: Arnd Bergmann <arnd@xxxxxxxx>
> Signed-off-by: Jerome Brunet <jbrunet@xxxxxxxxxxxx>

Silences the warning and makes the code more readable without adding any
new helpers. Awesome!

Reviewed-by: Justin Stitt <justinstitt@xxxxxxxxxx>
> ---
>  sound/soc/meson/aiu.c | 19 ++++---------------
>  sound/soc/meson/aiu.h |  1 -
>  2 files changed, 4 insertions(+), 16 deletions(-)
>
> diff --git a/sound/soc/meson/aiu.c b/sound/soc/meson/aiu.c
> index 7109b81cc3d0..5d1419ed7a62 100644
> --- a/sound/soc/meson/aiu.c
> +++ b/sound/soc/meson/aiu.c
> @@ -212,11 +212,12 @@ static const char * const aiu_spdif_ids[] = {
>  static int aiu_clk_get(struct device *dev)
>  {
>  	struct aiu *aiu = dev_get_drvdata(dev);
> +	struct clk *pclk;
>  	int ret;
>
> -	aiu->pclk = devm_clk_get(dev, "pclk");
> -	if (IS_ERR(aiu->pclk))
> -		return dev_err_probe(dev, PTR_ERR(aiu->pclk), "Can't get the aiu pclk\n");
> +	pclk = devm_clk_get_enabled(dev, "pclk");
> +	if (IS_ERR(pclk))
> +		return dev_err_probe(dev, PTR_ERR(pclk), "Can't get the aiu pclk\n");
>
>  	aiu->spdif_mclk = devm_clk_get(dev, "spdif_mclk");
>  	if (IS_ERR(aiu->spdif_mclk))
> @@ -233,18 +234,6 @@ static int aiu_clk_get(struct device *dev)
>  	if (ret)
>  		return dev_err_probe(dev, ret, "Can't get the spdif clocks\n");
>
> -	ret = clk_prepare_enable(aiu->pclk);
> -	if (ret) {
> -		dev_err(dev, "peripheral clock enable failed\n");
> -		return ret;
> -	}
> -
> -	ret = devm_add_action_or_reset(dev,
> -				       (void(*)(void *))clk_disable_unprepare,
> -				       aiu->pclk);
> -	if (ret)
> -		dev_err(dev, "failed to add reset action on pclk");
> -
>  	return ret;
>  }
>
> diff --git a/sound/soc/meson/aiu.h b/sound/soc/meson/aiu.h
> index 393b6c2307e4..0f94c8bf6081 100644
> --- a/sound/soc/meson/aiu.h
> +++ b/sound/soc/meson/aiu.h
> @@ -33,7 +33,6 @@ struct aiu_platform_data {
>  };
>
>  struct aiu {
> -	struct clk *pclk;
>  	struct clk *spdif_mclk;
>  	struct aiu_interface i2s;
>  	struct aiu_interface spdif;
> --
> 2.43.0
>
Thanks
Justin