Re: [PATCH -next] backlight: gpio_backlight: Switch to use dev_err_probe() helper

From: Daniel Thompson <daniel.thompson@linaro.org>
To: Yang Yingliang <yangyingliang@huawei.com>
Cc: jingoohan1@gmail.com, linux-fbdev@vger.kernel.org,
	lee@kernel.org, dri-devel@lists.freedesktop.org
Subject: Re: [PATCH -next] backlight: gpio_backlight: Switch to use dev_err_probe() helper
Date: Mon, 26 Sep 2022 14:46:48 +0100	[thread overview]
Message-ID: <YzGtSPDMQNUf41Z9@maple.lan> (raw)
In-Reply-To: <20220926133819.1298856-1-yangyingliang@huawei.com>

On Mon, Sep 26, 2022 at 09:38:19PM +0800, Yang Yingliang wrote:
> In the probe path, dev_err() can be replaced with dev_err_probe()
> which will check if error code is -EPROBE_DEFER and prints the
> error name. It also sets the defer probe reason which can be
> checked later through debugfs. It's more simple in error path.

Needs an SoB.

> ---
>  drivers/video/backlight/gpio_backlight.c | 10 +++-------
>  1 file changed, 3 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c
> index 6f78d928f054..4ff3939e5f7e 100644
> --- a/drivers/video/backlight/gpio_backlight.c
> +++ b/drivers/video/backlight/gpio_backlight.c
> @@ -64,13 +64,9 @@ static int gpio_backlight_probe(struct platform_device *pdev)
>  	def_value = device_property_read_bool(dev, "default-on");
>
>  	gbl->gpiod = devm_gpiod_get(dev, NULL, GPIOD_ASIS);
> -	if (IS_ERR(gbl->gpiod)) {
> -		ret = PTR_ERR(gbl->gpiod);
> -		if (ret != -EPROBE_DEFER)
> -			dev_err(dev,
> -				"Error: The gpios parameter is missing or invalid.\n");
> -		return ret;
> -	}
> +	if (IS_ERR(gbl->gpiod))
> +		return dev_err_probe(dev, PTR_ERR(gbl->gpiod),
> +				     "Error: The gpios parameter is missing or invalid.\n");

Remove the "Error: The " from the beginning of the string:
dev_err_probe() adds an error tag and the resulting line will read
better with a "The " at the beginning.

Daniel.