linux-kernel - Re: [PATCH 1/2] dmaengine: ti: edma: add missed pm_runtime

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Message-ID: <9ce1c3bb-3af8-6f6e-6f8f-cf2ab091de84@ti.com>
Date:   Fri, 22 Nov 2019 09:50:48 +0200
From:   Peter Ujfalusi <peter.ujfalusi@...com>
To:     Chuhong Yuan <hslester96@...il.com>
CC:     Vinod Koul <vkoul@...nel.org>,
        Dan Williams <dan.j.williams@...el.com>,
        <dmaengine@...r.kernel.org>, <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 1/2] dmaengine: ti: edma: add missed pm_runtime_disable

Hi,

On 18/11/2019 9.37, Chuhong Yuan wrote:
> The driver forgets to call pm_runtime_disable in probe failure and
> remove.
> Add the calls and modify probe failure handling to fix it.
> 
> Fixes: 2b6b3b742019 ("ARM/dmaengine: edma: Merge the two drivers under drivers/dma/")
> Signed-off-by: Chuhong Yuan <hslester96@...il.com>
> ---
>  drivers/dma/ti/edma.c | 43 ++++++++++++++++++++++++++++---------------
>  1 file changed, 28 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/dma/ti/edma.c b/drivers/dma/ti/edma.c
> index ba7c4f07fcd6..8be32fd9f762 100644
> --- a/drivers/dma/ti/edma.c
> +++ b/drivers/dma/ti/edma.c
> @@ -2282,16 +2282,18 @@ static int edma_probe(struct platform_device *pdev)

Please move the pm_runtime_enable/get section just before
edma_setup_from_hw()

>  	ret = pm_runtime_get_sync(dev);
>  	if (ret < 0) {
>  		dev_err(dev, "pm_runtime_get_sync() failed\n");
> -		return ret;
> +		goto err_disable_pm;

Here you need:
	pm_runtime_disable(dev);
	return ret;

>  	}
>  
>  	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
>  	if (ret)
> -		return ret;
> +		goto err_disable_pm;
>  
>  	ecc = devm_kzalloc(dev, sizeof(*ecc), GFP_KERNEL);
> -	if (!ecc)
> -		return -ENOMEM;
> +	if (!ecc) {
> +		ret = -ENOMEM;
> +		goto err_disable_pm;
> +	}
>  
>  	ecc->dev = dev;
>  	ecc->id = pdev->id;
> @@ -2306,30 +2308,37 @@ static int edma_probe(struct platform_device *pdev)
>  		mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>  		if (!mem) {
>  			dev_err(dev, "no mem resource?\n");
> -			return -ENODEV;
> +			ret = -ENODEV;
> +			goto err_disable_pm;
>  		}
>  	}
>  	ecc->base = devm_ioremap_resource(dev, mem);
> -	if (IS_ERR(ecc->base))
> -		return PTR_ERR(ecc->base);
> +	if (IS_ERR(ecc->base)) {
> +		ret = PTR_ERR(ecc->base);
> +		goto err_disable_pm;
> +	}

None of the above changes needed since the pm_runtime initialization is
moved

>  	platform_set_drvdata(pdev, ecc);

here.

>  	/* Get eDMA3 configuration from IP */
>  	ret = edma_setup_from_hw(dev, info, ecc);
>  	if (ret)
> -		return ret;
> +		goto err_disable_pm;
>  
>  	/* Allocate memory based on the information we got from the IP */
>  	ecc->slave_chans = devm_kcalloc(dev, ecc->num_channels,
>  					sizeof(*ecc->slave_chans), GFP_KERNEL);
> -	if (!ecc->slave_chans)
> -		return -ENOMEM;
> +	if (!ecc->slave_chans) {
> +		ret = -ENOMEM;
> +		goto err_disable_pm;
> +	}
>  
>  	ecc->slot_inuse = devm_kcalloc(dev, BITS_TO_LONGS(ecc->num_slots),
>  				       sizeof(unsigned long), GFP_KERNEL);
> -	if (!ecc->slot_inuse)
> -		return -ENOMEM;
> +	if (!ecc->slot_inuse) {
> +		ret = -ENOMEM;
> +		goto err_disable_pm;
> +	}

and this does not apply since we have the
	ecc->channels_mask = devm_kcalloc()
in here.

If you rebase, then I would suggest to combine the memory allocation
checks into one:
if (!ecc->slave_chans || !ecc->slot_inuse | !ecc->channels_mask) {
	ret = -ENOMEM;
	goto err_disable_pm;
}

>  
>  	ecc->default_queue = info->default_queue;
>  
> @@ -2368,7 +2377,7 @@ static int edma_probe(struct platform_device *pdev)
>  				       ecc);
>  		if (ret) {
>  			dev_err(dev, "CCINT (%d) failed --> %d\n", irq, ret);
> -			return ret;
> +			goto err_disable_pm;
>  		}
>  		ecc->ccint = irq;
>  	}
> @@ -2384,7 +2393,7 @@ static int edma_probe(struct platform_device *pdev)
>  				       ecc);
>  		if (ret) {
>  			dev_err(dev, "CCERRINT (%d) failed --> %d\n", irq, ret);
> -			return ret;
> +			goto err_disable_pm;
>  		}
>  		ecc->ccerrint = irq;
>  	}
> @@ -2392,7 +2401,8 @@ static int edma_probe(struct platform_device *pdev)
>  	ecc->dummy_slot = edma_alloc_slot(ecc, EDMA_SLOT_ANY);
>  	if (ecc->dummy_slot < 0) {
>  		dev_err(dev, "Can't allocate PaRAM dummy slot\n");
> -		return ecc->dummy_slot;
> +		ret = ecc->dummy_slot;
> +		goto err_disable_pm;
>  	}
>  
>  	queue_priority_mapping = info->queue_priority_mapping;
> @@ -2473,6 +2483,8 @@ static int edma_probe(struct platform_device *pdev)
>  
>  err_reg1:
>  	edma_free_slot(ecc, ecc->dummy_slot);
> +err_disable_pm:

Please add:
	pm_runtime_put_sync(dev);

> +	pm_runtime_disable(dev);
>  	return ret;
>  }
>  
> @@ -2503,6 +2515,7 @@ static int edma_remove(struct platform_device *pdev)
>  	if (ecc->dma_memcpy)
>  		dma_async_device_unregister(ecc->dma_memcpy);
>  	edma_free_slot(ecc, ecc->dummy_slot);

Here also:
	pm_runtime_put_sync(dev);


> +	pm_runtime_disable(dev);
>  
>  	return 0;
>  }
> 

- Péter

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