Re: [PATCH v1] Revert "dmaengine: stm32-mdma: Add a check on read_u32_array"

[Pierre Yves MORDRET]

On 3/25/19 4:25 PM, Vinod Koul wrote:
> On 25-03-19, 15:46, Pierre-Yves MORDRET wrote:
> 
> Please use the right subsystem name dmaengine, revert is not a subsystem
> name!

ok. sorry. I thought revert keyword was correct.

> 
>> This reverts commit 906b40b246b0acb54c4dc97e815cf734761c9820.
> 
> This should use the cannonical form for commits commit-sha1: ("title....") 

ok.

>>
>> As stated by bindings "st,ahb-addr-masks" is optional.
>> The statement inserted by this commit makes this property
>> mandatory and prevents MDMA to be probed in case property not present.
>>
>> Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@xxxxxx>
>> ---
>>  drivers/dma/stm32-mdma.c | 4 +---
>>  1 file changed, 1 insertion(+), 3 deletions(-)
>>
>> diff --git a/drivers/dma/stm32-mdma.c b/drivers/dma/stm32-mdma.c
>> index 4e0eede..ac0301b 100644
>> --- a/drivers/dma/stm32-mdma.c
>> +++ b/drivers/dma/stm32-mdma.c
>> @@ -1578,11 +1578,9 @@ static int stm32_mdma_probe(struct platform_device *pdev)
>>  
>>  	dmadev->nr_channels = nr_channels;
>>  	dmadev->nr_requests = nr_requests;
>> -	ret = device_property_read_u32_array(&pdev->dev, "st,ahb-addr-masks",
>> +	device_property_read_u32_array(&pdev->dev, "st,ahb-addr-masks",
>>  				       dmadev->ahb_addr_masks,
>>  				       count);
>> -	if (ret)
>> -		return ret;
>>  	dmadev->nr_ahb_addr_masks = count;
> 
> so if st,ahb-addr-masks is not present what value does count contain?

whether "st,ahb-addr-masks" present count will hold the number of mask.
otherwise sets to "0" by driver.

	count = device_property_read_u32_array(&pdev->dev, "st,ahb-addr-masks",
					       NULL, 0);
	if (count < 0)
		count = 0;
> 
>>  
>>  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> -- 
>> 2.7.4
>