Re: [PATCH v1 1/1] leds: is31fl319x: Wrap mutex_destroy() for devm_add_action_or_rest()

From: Vincent Knecht
Date: Sat Nov 05 2022 - 08:39:12 EST


Le samedi 05 novembre 2022 à 01:59 +0200, Andy Shevchenko a écrit :
> Clang complains that devm_add_action() takes a parameter with a wrong type:
>
> warning: cast from 'void (*)(struct mutex *)' to 'void (*)(void *)' converts to incompatible function type [-Wcast-
> function-type-strict]
>     err = devm_add_action(dev, (void (*)(void *))mutex_destroy, &is31->lock);
>                                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>     1 warning generated.
>
> It appears that the commit e1af5c815586 ("leds: is31fl319x: Fix devm vs.
> non-devm ordering") missed two things:
> - while mention devm_add_action_or_reset() the actual change got
>   devm_add_action() call by unknown reason
> - strictly speaking the parameter is not compatible by type
>
> Fix both issues by switching to devm_add_action_or_reset() and adding a
> wrapper for mutex_destroy() call.
>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Fixes: e1af5c815586 ("leds: is31fl319x: Fix devm vs. non-devm ordering")
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> ---
>  drivers/leds/leds-is31fl319x.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/leds/leds-is31fl319x.c b/drivers/leds/leds-is31fl319x.c
> index 52b59b62f437..6f94ad83e066 100644
> --- a/drivers/leds/leds-is31fl319x.c
> +++ b/drivers/leds/leds-is31fl319x.c
> @@ -494,6 +494,11 @@ static inline int is31fl3196_db_to_gain(u32 dezibel)
>         return dezibel / IS31FL3196_AUDIO_GAIN_DB_STEP;
>  }
>  
> +static void is31f1319x_mutex_destroy(void *lock)
> +{
> +       mutex_destroy(lock);
> +}
> +
>  static int is31fl319x_probe(struct i2c_client *client)
>  {
>         struct is31fl319x_chip *is31;
> @@ -510,7 +515,7 @@ static int is31fl319x_probe(struct i2c_client *client)
>                 return -ENOMEM;
>  
>         mutex_init(&is31->lock);
> -       err = devm_add_action(dev, (void (*)(void *))mutex_destroy, &is31->lock);
> +       err = devm_add_action_or_reset(dev, is31f1319x_mutex_destroy, &is31->lock);
>         if (err)
>                 return err;
>  

LED still works fine after applying this patch,
also after rmmod'ing and modprobe'ing again.
Please let me know if something else should be tested.
Thank you !

Tested-by: Vincent Knecht <vincent.knecht@xxxxxxxxxx>