Re: [PATCH -next] power: supply: ltc3651-charger: Fix wrong pointer passed to PTR_ERR()

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Wed, May 17, 2017 at 12:11:32PM +0000, Wei Yongjun wrote:
> From: Wei Yongjun <weiyongjun1@huawei.com>
> 
> PTR_ERR should access the value just tested by IS_ERR, otherwise
> the wrong error code will be returned.
> 
> Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>

This does fix the issue, but maybe we want to use PTR_ERR_OR_ZERO()?

	ltc3651_charger->acpr_gpio = devm_gpiod_get(&pdev->dev,
					"lltc,acpr", GPIOD_IN);
	ret = PTR_ERR_OR_ZERO(ltc3651_charger->acpr_gpio);
	if (ret)
		...

Or even

	err = PTR_ERR_OR_ZERO((ltc3651_charger->acpr_gpio =
		devm_gpiod_get(&pdev->dev, "lltc,acpr", GPIOD_IN)));
	if (err)
		...

To make sure we never mix up pointer. Maybe we need ERR_OR_ASSIGN(ptr1,
ptr2) to avoid the ugly assignment in argument above...

Thanks.

> ---
>  drivers/power/supply/ltc3651-charger.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/power/supply/ltc3651-charger.c b/drivers/power/supply/ltc3651-charger.c
> index 5f8d5c0..eea63ff 100644
> --- a/drivers/power/supply/ltc3651-charger.c
> +++ b/drivers/power/supply/ltc3651-charger.c
> @@ -110,21 +110,21 @@ static int ltc3651_charger_probe(struct platform_device *pdev)
>  	ltc3651_charger->acpr_gpio = devm_gpiod_get(&pdev->dev,
>  					"lltc,acpr", GPIOD_IN);
>  	if (IS_ERR(ltc3651_charger->acpr_gpio)) {
> -		ret = PTR_ERR(ltc3651_charger->charger);
> +		ret = PTR_ERR(ltc3651_charger->acpr_gpio);
>  		dev_err(&pdev->dev, "Failed to acquire acpr GPIO: %d\n", ret);
>  		return ret;
>  	}
>  	ltc3651_charger->fault_gpio = devm_gpiod_get_optional(&pdev->dev,
>  					"lltc,fault", GPIOD_IN);
>  	if (IS_ERR(ltc3651_charger->fault_gpio)) {
> -		ret = PTR_ERR(ltc3651_charger->charger);
> +		ret = PTR_ERR(ltc3651_charger->fault_gpio);
>  		dev_err(&pdev->dev, "Failed to acquire fault GPIO: %d\n", ret);
>  		return ret;
>  	}
>  	ltc3651_charger->chrg_gpio = devm_gpiod_get_optional(&pdev->dev,
>  					"lltc,chrg", GPIOD_IN);
>  	if (IS_ERR(ltc3651_charger->chrg_gpio)) {
> -		ret = PTR_ERR(ltc3651_charger->charger);
> +		ret = PTR_ERR(ltc3651_charger->chrg_gpio);
>  		dev_err(&pdev->dev, "Failed to acquire chrg GPIO: %d\n", ret);
>  		return ret;
>  	}
> 

-- 
Dmitry