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From: =?utf-8?Q?Krzysztof_Ha=C5=82asa?= <khalasa@piap.pl>
To: Chen Ni <nichen@iscas.ac.cn>
Cc: <sakari.ailus@linux.intel.com>,  <mchehab@kernel.org>,
  <linux-media@vger.kernel.org>,  <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] media: i2c: ar0521: Check return value of
 devm_gpiod_get_optional() in ar0521_probe()
In-Reply-To: <20260130041815.2988011-1-nichen@iscas.ac.cn> (Chen Ni's message
	of "Fri, 30 Jan 2026 12:18:15 +0800")
References: <20260130041815.2988011-1-nichen@iscas.ac.cn>
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Date: Fri, 06 Feb 2026 07:39:00 +0100
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Hi Chen,

Chen Ni <nichen@iscas.ac.cn> writes:

> The devm_gpiod_get_optional() function may return an error pointer
> (ERR_PTR) in case of a genuine failure during GPIO acquisition, not just
> NULL which indicates the legitimate absence of an optional GPIO.

Well, it seems only right. Though I would prefer all-caps "GPIO" in
kernel messages. Either way,

Acked-by: Krzysztof Ha=C5=82asa <khalasa@piap.pl>

> --- a/drivers/media/i2c/ar0521.c
> +++ b/drivers/media/i2c/ar0521.c
> @@ -1094,6 +1094,9 @@ static int ar0521_probe(struct i2c_client *client)
>         /* Request optional reset pin (usually active low) and assert it =
*/
>         sensor->reset_gpio =3D devm_gpiod_get_optional(dev, "reset",
>                                                      GPIOD_OUT_HIGH);
> +       if (IS_ERR(sensor->reset_gpio))
> +               return dev_err_probe(dev, PTR_ERR(sensor->reset_gpio),
> +                                    "failed to get reset gpio\n");
>
>         v4l2_i2c_subdev_init(&sensor->sd, client, &ar0521_subdev_ops);
>

--=20
Krzysztof "Chris" Ha=C5=82asa

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