Re: [PATCH 06/15] drm/panfrost: properly handle error in probe

From: Steven Price <steven.price@arm.com>
To: "Clément Péron" <peron.clem@gmail.com>,
	"Rob Herring" <robh@kernel.org>,
	"Tomeu Vizoso" <tomeu.vizoso@collabora.com>,
	"Alyssa Rosenzweig" <alyssa.rosenzweig@collabora.com>,
	"Viresh Kumar" <vireshk@kernel.org>, "Nishanth Menon" <nm@ti.com>,
	"Stephen Boyd" <sboyd@kernel.org>,
	"Maxime Ripard" <mripard@kernel.org>,
	"Chen-Yu Tsai" <wens@csie.org>
Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 06/15] drm/panfrost: properly handle error in probe
Date: Thu, 28 May 2020 14:22:47 +0100	[thread overview]
Message-ID: <6a5915af-680f-0e9f-1502-ccb4f8d3d199@arm.com> (raw)
In-Reply-To: <20200510165538.19720-7-peron.clem@gmail.com>

On 10/05/2020 17:55, Clément Péron wrote:
> Introduce a boolean to know if opp table has been added.
> 
> With this, we can call panfrost_devfreq_fini() in case of error
> and release what has been initialised.
> 
> Signed-off-by: Clément Péron <peron.clem@gmail.com>

LGTM:

Reviewed-by: Steven Price <steven.price@arm.com>

> ---
>   drivers/gpu/drm/panfrost/panfrost_devfreq.c | 25 ++++++++++++++++-----
>   drivers/gpu/drm/panfrost/panfrost_devfreq.h |  1 +
>   2 files changed, 20 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.c b/drivers/gpu/drm/panfrost/panfrost_devfreq.c
> index 78753cfb59fb..d9007f44b772 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_devfreq.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.c
> @@ -101,6 +101,7 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev)
>   		return 0;
>   	else if (ret)
>   		return ret;
> +	pfdevfreq->opp_of_table_added = true;
>   
>   	spin_lock_init(&pfdevfreq->lock);
>   
> @@ -109,8 +110,10 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev)
>   	cur_freq = clk_get_rate(pfdev->clock);
>   
>   	opp = devfreq_recommended_opp(dev, &cur_freq, 0);
> -	if (IS_ERR(opp))
> -		return PTR_ERR(opp);
> +	if (IS_ERR(opp)) {
> +		ret = PTR_ERR(opp);
> +		goto err_fini;
> +	}
>   
>   	panfrost_devfreq_profile.initial_freq = cur_freq;
>   	dev_pm_opp_put(opp);
> @@ -119,8 +122,8 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev)
>   					  DEVFREQ_GOV_SIMPLE_ONDEMAND, NULL);
>   	if (IS_ERR(devfreq)) {
>   		DRM_DEV_ERROR(dev, "Couldn't initialize GPU devfreq\n");
> -		dev_pm_opp_of_remove_table(dev);
> -		return PTR_ERR(devfreq);
> +		ret = PTR_ERR(devfreq);
> +		goto err_fini;
>   	}
>   	pfdevfreq->devfreq = devfreq;
>   
> @@ -131,15 +134,25 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev)
>   		pfdevfreq->cooling = cooling;
>   
>   	return 0;
> +
> +err_fini:
> +	panfrost_devfreq_fini(pfdev);
> +	return ret;
>   }
>   
>   void panfrost_devfreq_fini(struct panfrost_device *pfdev)
>   {
>   	struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq;
>   
> -	if (pfdevfreq->cooling)
> +	if (pfdevfreq->cooling) {
>   		devfreq_cooling_unregister(pfdevfreq->cooling);
> -	dev_pm_opp_of_remove_table(&pfdev->pdev->dev);
> +		pfdevfreq->cooling = NULL;
> +	}
> +
> +	if (pfdevfreq->opp_of_table_added) {
> +		dev_pm_opp_of_remove_table(&pfdev->pdev->dev);
> +		pfdevfreq->opp_of_table_added = false;
> +	}
>   }
>   
>   void panfrost_devfreq_resume(struct panfrost_device *pfdev)
> diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.h b/drivers/gpu/drm/panfrost/panfrost_devfreq.h
> index e6629900a618..add203cb00c2 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_devfreq.h
> +++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.h
> @@ -15,6 +15,7 @@ struct panfrost_device;
>   struct panfrost_devfreq {
>   	struct devfreq *devfreq;
>   	struct thermal_cooling_device *cooling;
> +	bool opp_of_table_added;
>   
>   	ktime_t busy_time;
>   	ktime_t idle_time;
>