Re: [PATCH] drivers/iio/adc/at91_adc.c: use devm_ functions

[Jonathan Cameron <jic23@kernel.org>]

Lars-Peter,

Are you happy with this updated version?  Can't immediately find any response
from you to it.

Jonathan
> From: Julia Lawall <Julia.Lawall@lip6.fr>
> 
> The various devm_ functions allocate memory that is released when a driver
> detaches.  This patch uses these functions for data that is allocated in
> the probe function of a platform device and is only freed in the remove
> function.
> 
> The call to platform_get_resource(pdev, IORESOURCE_MEM, 0) is moved coser
> to the call to devm_request_and_ioremap, which is th first use of the
> result of platform_get_resource.
> 
> This does not use devm_request_irq to ensure that free_irq is executed
> before its idev argument is freed.
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
> 
> ---
>  drivers/iio/adc/at91_adc.c |   41 ++++++++---------------------------------
>  1 file changed, 8 insertions(+), 33 deletions(-)
> 
> diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
> index f61780a..3506e3d 100644
> --- a/drivers/iio/adc/at91_adc.c
> +++ b/drivers/iio/adc/at91_adc.c
> @@ -545,13 +545,6 @@ static int __devinit at91_adc_probe(struct platform_device *pdev)
>  		goto error_free_device;
>  	}
> 
> -	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> -	if (!res) {
> -		dev_err(&pdev->dev, "No resource defined\n");
> -		ret = -ENXIO;
> -		goto error_ret;
> -	}
> -
>  	platform_set_drvdata(pdev, idev);
> 
>  	idev->dev.parent = &pdev->dev;
> @@ -566,18 +559,13 @@ static int __devinit at91_adc_probe(struct platform_device *pdev)
>  		goto error_free_device;
>  	}
> 
> -	if (!request_mem_region(res->start, resource_size(res),
> -				"AT91 adc registers")) {
> -		dev_err(&pdev->dev, "Resources are unavailable.\n");
> -		ret = -EBUSY;
> -		goto error_free_device;
> -	}
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> 
> -	st->reg_base = ioremap(res->start, resource_size(res));
> +	st->reg_base = devm_request_and_ioremap(&pdev->dev, res);
>  	if (!st->reg_base) {
>  		dev_err(&pdev->dev, "Failed to map registers.\n");
>  		ret = -ENOMEM;
> -		goto error_release_mem;
> +		goto error_free_device;
>  	}
> 
>  	/*
> @@ -592,10 +580,10 @@ static int __devinit at91_adc_probe(struct platform_device *pdev)
>  			  idev);
>  	if (ret) {
>  		dev_err(&pdev->dev, "Failed to allocate IRQ.\n");
> -		goto error_unmap_reg;
> +		goto error_free_device;
>  	}
> 
> -	st->clk = clk_get(&pdev->dev, "adc_clk");
> +	st->clk = devm_clk_get(&pdev->dev, "adc_clk");
>  	if (IS_ERR(st->clk)) {
>  		dev_err(&pdev->dev, "Failed to get the clock.\n");
>  		ret = PTR_ERR(st->clk);
> @@ -605,7 +593,7 @@ static int __devinit at91_adc_probe(struct platform_device *pdev)
>  	ret = clk_prepare(st->clk);
>  	if (ret) {
>  		dev_err(&pdev->dev, "Could not prepare the clock.\n");
> -		goto error_free_clk;
> +		goto error_free_irq;
>  	}
> 
>  	ret = clk_enable(st->clk);
> @@ -614,7 +602,7 @@ static int __devinit at91_adc_probe(struct platform_device *pdev)
>  		goto error_unprepare_clk;
>  	}
> 
> -	st->adc_clk = clk_get(&pdev->dev, "adc_op_clk");
> +	st->adc_clk = devm_clk_get(&pdev->dev, "adc_op_clk");
>  	if (IS_ERR(st->adc_clk)) {
>  		dev_err(&pdev->dev, "Failed to get the ADC clock.\n");
>  		ret = PTR_ERR(st->clk);
> @@ -624,7 +612,7 @@ static int __devinit at91_adc_probe(struct platform_device *pdev)
>  	ret = clk_prepare(st->adc_clk);
>  	if (ret) {
>  		dev_err(&pdev->dev, "Could not prepare the ADC clock.\n");
> -		goto error_free_adc_clk;
> +		goto error_disable_clk;
>  	}
> 
>  	ret = clk_enable(st->adc_clk);
> @@ -697,20 +685,12 @@ error_disable_adc_clk:
>  	clk_disable(st->adc_clk);
>  error_unprepare_adc_clk:
>  	clk_unprepare(st->adc_clk);
> -error_free_adc_clk:
> -	clk_put(st->adc_clk);
>  error_disable_clk:
>  	clk_disable(st->clk);
>  error_unprepare_clk:
>  	clk_unprepare(st->clk);
> -error_free_clk:
> -	clk_put(st->clk);
>  error_free_irq:
>  	free_irq(st->irq, idev);
> -error_unmap_reg:
> -	iounmap(st->reg_base);
> -error_release_mem:
> -	release_mem_region(res->start, resource_size(res));
>  error_free_device:
>  	iio_device_free(idev);
>  error_ret:
> @@ -720,20 +700,15 @@ error_ret:
>  static int __devexit at91_adc_remove(struct platform_device *pdev)
>  {
>  	struct iio_dev *idev = platform_get_drvdata(pdev);
> -	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>  	struct at91_adc_state *st = iio_priv(idev);
> 
>  	iio_device_unregister(idev);
>  	at91_adc_trigger_remove(idev);
>  	at91_adc_buffer_remove(idev);
>  	clk_disable_unprepare(st->adc_clk);
> -	clk_put(st->adc_clk);
>  	clk_disable(st->clk);
>  	clk_unprepare(st->clk);
> -	clk_put(st->clk);
>  	free_irq(st->irq, idev);
> -	iounmap(st->reg_base);
> -	release_mem_region(res->start, resource_size(res));
>  	iio_device_free(idev);
> 
>  	return 0;
>