# Re: \[PATCH 4/9\] backlight: atmel-pwm-bl: clean up probe error handling

- From: Jean-Christophe PLAGNIOL-VILLARD \<hidden\>
- Date: 2013-10-25 13:35:42 
- List: linux-fbdev
- Page: https://ratatoskr.run/linux-fbdev/2013/10/4138936
- Thread: https://ratatoskr.run/linux-fbdev/2013/10/4137973/t.md

```text
On 11:55 Wed 23 Oct     , Johan Hovold wrote:
> Clean up probe error handling by checking parameters before any
> allocations and removing an obsolete error label. Also remove
> unnecessary reset of private gpio number.
> 
> Acked-by: Jingoo Han <redacted>
> Signed-off-by: Johan Hovold <redacted>
> ---
>  drivers/video/backlight/atmel-pwm-bl.c | 31 ++++++++++++-------------------
>  1 file changed, 12 insertions(+), 19 deletions(-)
> 
> diff --git a/drivers/video/backlight/atmel-pwm-bl.c b/drivers/video/backlight/atmel-pwm-bl.c
> index cc5a5ed..52a8134 100644
> --- a/drivers/video/backlight/atmel-pwm-bl.c
> +++ b/drivers/video/backlight/atmel-pwm-bl.c
> @@ -126,40 +126,33 @@ static int atmel_pwm_bl_probe(struct platform_device *pdev)
>  	struct atmel_pwm_bl *pwmbl;
>  	int retval;
>  
> +	pdata = dev_get_platdata(&pdev->dev);
> +	if (!pdata)
> +		return -ENODEV;
> +
> +	if (pdata->pwm_compare_max < pdata->pwm_duty_max ||
> +			pdata->pwm_duty_min > pdata->pwm_duty_max ||
> +			pdata->pwm_frequency = 0)
> +		return -EINVAL;
> +
>  	pwmbl = devm_kzalloc(&pdev->dev, sizeof(struct atmel_pwm_bl),
>  				GFP_KERNEL);
>  	if (!pwmbl)
>  		return -ENOMEM;
>  
>  	pwmbl->pdev = pdev;
> -
> -	pdata = dev_get_platdata(&pdev->dev);
> -	if (!pdata) {
> -		retval = -ENODEV;
> -		goto err_free_mem;
> -	}
> -
> -	if (pdata->pwm_compare_max < pdata->pwm_duty_max ||
> -			pdata->pwm_duty_min > pdata->pwm_duty_max ||
> -			pdata->pwm_frequency = 0) {
> -		retval = -EINVAL;
> -		goto err_free_mem;
> -	}
> -
>  	pwmbl->pdata = pdata;
>  	pwmbl->gpio_on = pdata->gpio_on;
>  
>  	retval = pwm_channel_alloc(pdata->pwm_channel, &pwmbl->pwmc);
>  	if (retval)
> -		goto err_free_mem;
> +		return retval;
>  
>  	if (pwmbl->gpio_on != -1) {
gpio_is_valid here
>  		retval = devm_gpio_request(&pdev->dev, pwmbl->gpio_on,
>  					"gpio_atmel_pwm_bl");
> -		if (retval) {
> -			pwmbl->gpio_on = -1;
> +		if (retval)
>  			goto err_free_pwm;
> -		}
>  
>  		/* Turn display off by default. */
>  		retval = gpio_direction_output(pwmbl->gpio_on,
> @@ -197,7 +190,7 @@ static int atmel_pwm_bl_probe(struct platform_device *pdev)
>  
>  err_free_pwm:
>  	pwm_channel_free(&pwmbl->pwmc);
> -err_free_mem:
> +
>  	return retval;
>  }
>  
> -- 
> 1.8.4
> 
```