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Date:   Fri, 30 Apr 2021 18:08:36 +0100
From:   Jonathan Cameron <Jonathan.Cameron@Huawei.com>
To:     Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
CC:     <linuxarm@huawei.com>, <mauro.chehab@huawei.com>,
        Dmitry Osipenko <digetx@gmail.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Jonathan Hunter" <jonathanh@nvidia.com>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Thierry Reding <thierry.reding@gmail.com>,
        <devel@driverdev.osuosl.org>, <linux-kernel@vger.kernel.org>,
        <linux-media@vger.kernel.org>, <linux-tegra@vger.kernel.org>
Subject: Re: [PATCH v4 25/79] staging: media: tegra-vde: use
 pm_runtime_resume_and_get()
Message-ID: <20210430180836.00006da4@Huawei.com>
In-Reply-To: <bc2b9048d4ad510eec97988ce8f3fd0d2bb26f39.1619621413.git.mchehab+huawei@kernel.org>
References: <cover.1619621413.git.mchehab+huawei@kernel.org>
        <bc2b9048d4ad510eec97988ce8f3fd0d2bb26f39.1619621413.git.mchehab+huawei@kernel.org>
Organization: Huawei Technologies Research and Development (UK) Ltd.
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On Wed, 28 Apr 2021 16:51:46 +0200
Mauro Carvalho Chehab <mchehab+huawei@kernel.org> wrote:

> Commit dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
> added pm_runtime_resume_and_get() in order to automatically handle
> dev->power.usage_count decrement on errors.
> 
> Use the new API, in order to cleanup the error check logic.
> 
> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
LGTM

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

> ---
>  drivers/staging/media/tegra-vde/vde.c | 19 ++++++++++++++++---
>  1 file changed, 16 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/staging/media/tegra-vde/vde.c b/drivers/staging/media/tegra-vde/vde.c
> index 28845b5bafaf..1cdacb3f781c 100644
> --- a/drivers/staging/media/tegra-vde/vde.c
> +++ b/drivers/staging/media/tegra-vde/vde.c
> @@ -775,9 +775,9 @@ static int tegra_vde_ioctl_decode_h264(struct tegra_vde *vde,
>  	if (ret)
>  		goto release_dpb_frames;
>  
> -	ret = pm_runtime_get_sync(dev);
> +	ret = pm_runtime_resume_and_get(dev);
>  	if (ret < 0)
> -		goto put_runtime_pm;
> +		goto unlock;
>  
>  	/*
>  	 * We rely on the VDE registers reset value, otherwise VDE
> @@ -843,6 +843,8 @@ static int tegra_vde_ioctl_decode_h264(struct tegra_vde *vde,
>  put_runtime_pm:
>  	pm_runtime_mark_last_busy(dev);
>  	pm_runtime_put_autosuspend(dev);
> +
> +unlock:
>  	mutex_unlock(&vde->lock);
>  
>  release_dpb_frames:
> @@ -1069,11 +1071,17 @@ static int tegra_vde_probe(struct platform_device *pdev)
>  	 * power-cycle it in order to put hardware into a predictable lower
>  	 * power state.
>  	 */
> -	pm_runtime_get_sync(dev);
> +	if (pm_runtime_resume_and_get(dev) < 0)
> +		goto err_pm_runtime;
> +
>  	pm_runtime_put(dev);
>  
>  	return 0;
>  
> +err_pm_runtime:
> +	pm_runtime_dont_use_autosuspend(dev);
> +	pm_runtime_disable(dev);
> +
>  err_deinit_iommu:
>  	tegra_vde_iommu_deinit(vde);
>  
> @@ -1089,7 +1097,12 @@ static int tegra_vde_remove(struct platform_device *pdev)
>  	struct tegra_vde *vde = platform_get_drvdata(pdev);
>  	struct device *dev = &pdev->dev;
>  
> +	/*
> +	 * As it increments RPM usage_count even on errors, we don't need to
> +	 * check the returned code here.
> +	 */
>  	pm_runtime_get_sync(dev);
> +
>  	pm_runtime_dont_use_autosuspend(dev);
>  	pm_runtime_disable(dev);
>