Re: [PATCH -next] watchdog: jz4740: Fix return value check in jz4740_wdt_probe()

[Guenter Roeck <linux@roeck-us.net>]

On Thu, Mar 04, 2021 at 04:59:09AM +0000, 'Wei Yongjun wrote:
> From: Wei Yongjun <weiyongjun1@huawei.com>
> 
> In case of error, the function device_node_to_regmap() returns
> ERR_PTR() and never returns NULL. The NULL test in the return
> value check should be replaced with IS_ERR().
> 
> Fixes: 6d532143c915 ("watchdog: jz4740: Use regmap provided by TCU driver")
> Reported-by: Hulk Robot <hulkci@huawei.com>
> Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
> Acked-by: Paul Cercueil <paul@crapouillou.net>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
>  drivers/watchdog/jz4740_wdt.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/watchdog/jz4740_wdt.c b/drivers/watchdog/jz4740_wdt.c
> index bdf9564efa29..395bde79e292 100644
> --- a/drivers/watchdog/jz4740_wdt.c
> +++ b/drivers/watchdog/jz4740_wdt.c
> @@ -176,9 +176,9 @@ static int jz4740_wdt_probe(struct platform_device *pdev)
>  	watchdog_set_drvdata(jz4740_wdt, drvdata);
>  
>  	drvdata->map = device_node_to_regmap(dev->parent->of_node);
> -	if (!drvdata->map) {
> +	if (IS_ERR(drvdata->map)) {
>  		dev_err(dev, "regmap not found\n");
> -		return -EINVAL;
> +		return PTR_ERR(drvdata->map);
>  	}
>  
>  	return devm_watchdog_register_device(dev, &drvdata->wdt);