linux-kernel - Re: [PATCH v2 11/19] PM / devfreq: tegra: De-initialize properly on driver's probe error

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Date:   Tue, 16 Apr 2019 15:21:57 +0900
From:   Chanwoo Choi <cw00.choi@...sung.com>
To:     Dmitry Osipenko <digetx@...il.com>,
        Thierry Reding <thierry.reding@...il.com>,
        Jonathan Hunter <jonathanh@...dia.com>,
        MyungJoo Ham <myungjoo.ham@...sung.com>,
        Kyungmin Park <kyungmin.park@...sung.com>,
        Tomeu Vizoso <tomeu.vizoso@...labora.com>
Cc:     linux-tegra@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-pm@...r.kernel.org
Subject: Re: [PATCH v2 11/19] PM / devfreq: tegra: De-initialize properly on
 driver's probe error

Hi Dmitry,

I already replied against patch6 about the exception handling
of tegra_devfreq_probe(). This patchset split out the patch
related to error handling for probe(). I think that you can
squash the patches regarding of exception handling for probe()
to one patch instead of split out the multiple patches.

On 19. 4. 15. 오후 11:54, Dmitry Osipenko wrote:
> Reset hardware, disable ACTMON clock, release OPP's and free IRQ before
> removing devfreq device since there is no guarantee that interrupt
> handling won't run after masking interrupt in hardware.
> 
> Signed-off-by: Dmitry Osipenko <digetx@...il.com>
> ---
>  drivers/devfreq/tegra-devfreq.c | 53 ++++++++++++++++-----------------
>  1 file changed, 26 insertions(+), 27 deletions(-)
> 
> diff --git a/drivers/devfreq/tegra-devfreq.c b/drivers/devfreq/tegra-devfreq.c
> index 69b557df5084..a668e4fbc874 100644
> --- a/drivers/devfreq/tegra-devfreq.c
> +++ b/drivers/devfreq/tegra-devfreq.c
> @@ -663,28 +663,28 @@ static int tegra_devfreq_probe(struct platform_device *pdev)
>  
>  	irq = platform_get_irq(pdev, 0);
>  	if (irq < 0) {
> -		dev_err(&pdev->dev, "Failed to get IRQ: %d\n", irq);
> -		return irq;
> +		err = irq;
> +		dev_err(&pdev->dev, "Failed to get IRQ: %d\n", err);
> +		goto remove_opps;
>  	}
>  
>  	platform_set_drvdata(pdev, tegra);
>  
>  	tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock);
> -	tegra->devfreq = devm_devfreq_add_device(&pdev->dev,
> -						 &tegra_devfreq_profile,
> -						 "tegra_actmon",
> -						 NULL);
> +	tegra->devfreq = devfreq_add_device(&pdev->dev,
> +					    &tegra_devfreq_profile,
> +					    "tegra_actmon",
> +					    NULL);
>  	if (IS_ERR(tegra->devfreq)) {
>  		err = PTR_ERR(tegra->devfreq);
> -		return err;
> +		goto remove_opps;
>  	}
>  
> -	err = devm_request_threaded_irq(&pdev->dev, irq, NULL,
> -					actmon_thread_isr, IRQF_ONESHOT,
> -					"tegra-devfreq", tegra);
> +	err = request_threaded_irq(irq, NULL, actmon_thread_isr, IRQF_ONESHOT,
> +				   "tegra-devfreq", tegra);
>  	if (err) {
>  		dev_err(&pdev->dev, "Interrupt request failed\n");
> -		goto remove_opps;
> +		goto remove_devfreq;
>  	}
>  
>  	tegra->rate_change_nb.notifier_call = tegra_actmon_rate_notify_cb;
> @@ -692,14 +692,23 @@ static int tegra_devfreq_probe(struct platform_device *pdev)
>  	if (err) {
>  		dev_err(&pdev->dev,
>  			"Failed to register rate change notifier\n");
> -		goto remove_opps;
> +		goto disable_interrupt;
>  	}
>  
>  	return 0;
>  
> +disable_interrupt:
> +	free_irq(irq, tegra);
> +
> +remove_devfreq:
> +	devfreq_remove_device(tegra->devfreq);
> +
>  remove_opps:
>  	dev_pm_opp_remove_all_dynamic(&pdev->dev);
>  
> +	reset_control_reset(tegra->reset);
> +	clk_disable_unprepare(tegra->clock);
> +
>  	return err;
>  }
>  
> @@ -707,24 +716,14 @@ static int tegra_devfreq_remove(struct platform_device *pdev)
>  {
>  	struct tegra_devfreq *tegra = platform_get_drvdata(pdev);
>  	int irq = platform_get_irq(pdev, 0);
> -	u32 val;
> -	unsigned int i;
> -
> -	devm_devfreq_remove_device(&pdev->dev, tegra->devfreq);
> -	dev_pm_opp_remove_all_dynamic(&pdev->dev);
> -
> -	for (i = 0; i < ARRAY_SIZE(actmon_device_configs); i++) {
> -		val = device_readl(&tegra->devices[i], ACTMON_DEV_CTRL);
> -		val &= ~ACTMON_DEV_CTRL_ENB;
> -		device_writel(&tegra->devices[i], val, ACTMON_DEV_CTRL);
> -	}
> -
> -	actmon_write_barrier(tegra);
> -
> -	devm_free_irq(&pdev->dev, irq, tegra);
>  
>  	clk_notifier_unregister(tegra->emc_clock, &tegra->rate_change_nb);
> +	free_irq(irq, tegra);
> +
> +	devfreq_remove_device(tegra->devfreq);
> +	dev_pm_opp_remove_all_dynamic(&pdev->dev);
>  
> +	reset_control_reset(tegra->reset);
>  	clk_disable_unprepare(tegra->clock);
>  
>  	return 0;
> 


-- 
Best Regards,
Chanwoo Choi
Samsung Electronics