linux-kernel - Re: [PATCH v2 03/11] media: i2c: ov5645: Enable runtime PM after v4l2_async_register

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240924223740.GL7165@pendragon.ideasonboard.com>
Date: Wed, 25 Sep 2024 01:37:40 +0300
From: Laurent Pinchart <laurent.pinchart@...asonboard.com>
To: Prabhakar <prabhakar.csengg@...il.com>
Cc: Sakari Ailus <sakari.ailus@...ux.intel.com>,
	Kieran Bingham <kieran.bingham@...asonboard.com>,
	Tomi Valkeinen <tomi.valkeinen@...asonboard.com>,
	Jacopo Mondi <jacopo.mondi@...asonboard.com>,
	Mauro Carvalho Chehab <mchehab@...nel.org>,
	Hans Verkuil <hverkuil-cisco@...all.nl>,
	linux-media@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-renesas-soc@...r.kernel.org,
	Biju Das <biju.das.jz@...renesas.com>,
	Fabrizio Castro <fabrizio.castro.jz@...esas.com>,
	Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>
Subject: Re: [PATCH v2 03/11] media: i2c: ov5645: Enable runtime PM after
 v4l2_async_register_subdev()

Hi Prabhakar,

Thank you for the patch.

On Tue, Sep 10, 2024 at 06:06:02PM +0100, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>
> 
> To simplify the probe error path, enable runtime PM after the
> v4l2_async_register_subdev() call.
> 
> This change ensures that runtime PM is only enabled once the subdevice
> registration is successful, avoiding unnecessary cleanup in the error
> path.

The subdev could start being used as soon as it gets registered, so
runtime PM initialization should happen before
v4l2_async_register_subdev().

> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>
> ---
>  drivers/media/i2c/ov5645.c | 12 ++++--------
>  1 file changed, 4 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/media/i2c/ov5645.c b/drivers/media/i2c/ov5645.c
> index ab3a419df2df..78b86438c798 100644
> --- a/drivers/media/i2c/ov5645.c
> +++ b/drivers/media/i2c/ov5645.c
> @@ -1239,18 +1239,17 @@ static int ov5645_probe(struct i2c_client *client)
>  		goto power_down;
>  	}
>  
> -	pm_runtime_set_active(dev);
> -	pm_runtime_get_noresume(dev);
> -	pm_runtime_enable(dev);
> -
>  	ov5645_init_state(&ov5645->sd, NULL);
>  
>  	ret = v4l2_async_register_subdev(&ov5645->sd);
>  	if (ret < 0) {
>  		dev_err(dev, "could not register v4l2 device\n");
> -		goto err_pm_runtime;
> +		goto power_down;
>  	}
>  
> +	pm_runtime_set_active(dev);
> +	pm_runtime_get_noresume(dev);
> +	pm_runtime_enable(dev);
>  	pm_runtime_set_autosuspend_delay(dev, 1000);
>  	pm_runtime_use_autosuspend(dev);
>  	pm_runtime_mark_last_busy(dev);
> @@ -1258,9 +1257,6 @@ static int ov5645_probe(struct i2c_client *client)
>  
>  	return 0;
>  
> -err_pm_runtime:
> -	pm_runtime_disable(dev);
> -	pm_runtime_put_noidle(dev);
>  power_down:
>  	ov5645_set_power_off(dev);
>  free_entity:

-- 
Regards,

Laurent Pinchart