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

[Lars-Peter Clausen <lars@metafoo.de>]

On 08/14/2012 10:32 PM, Jonathan Cameron wrote:
> Lars-Peter,
> 
> Are you happy with this updated version?  Can't immediately find any response
> from you to it.
> 

I think it is ok, you can add my
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>.

One minor nitpick though.

> 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");

devm_request_and_ioremap will already print a error messages on it's own if
something goes wrong. So strictly speaking this one is redundant, but I don't
think it is necessary to do a resend just for this, maybe you can remove the
extra dev_err when you apply the patch.