Re: [PATCH 3/4] pwm: Mark free pwm IDs as used in alloc_pwms()

[Andy Shevchenko]

On Tue, Nov 15, 2022 at 10:15:14PM +0100, Uwe Kleine-König wrote:
> alloc_pwms() only identified a free range of IDs and this range was marked
> as used only later by pwmchip_add(). Instead let alloc_pwms() already do
> the marking (which makes the function actually allocating the range and so
> justifies the function name). This way access to the allocated_pwms
> bitfield is limited to two functions only.

Let's assume that developers will be cautious about properly freeing allocated
resources.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
> ---
>  drivers/pwm/core.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
> index 2338119a09d8..b43b24bd3c9f 100644
> --- a/drivers/pwm/core.c
> +++ b/drivers/pwm/core.c
> @@ -51,6 +51,8 @@ static int alloc_pwms(unsigned int count)
>  	if (start + count > MAX_PWMS)
>  		return -ENOSPC;
>  
> +	bitmap_set(allocated_pwms, start, count);
> +
>  	return start;
>  }
>  
> @@ -297,8 +299,6 @@ int pwmchip_add(struct pwm_chip *chip)
>  		radix_tree_insert(&pwm_tree, pwm->pwm, pwm);
>  	}
>  
> -	bitmap_set(allocated_pwms, chip->base, chip->npwm);
> -
>  	INIT_LIST_HEAD(&chip->list);
>  	list_add(&chip->list, &pwm_chips);
>  
> -- 
> 2.38.1
> 

-- 
With Best Regards,
Andy Shevchenko