Re: [PATCH 2/4] msm: iommu: Rework clock logic and add IOMMU bus clock control

[Stepan Moskovchenko <stepanm@codeaurora.org>]

On 2/24/2011 11:29 PM, Trilok Soni wrote:
> Hi Steve,

Hello

>> @@ -130,117 +131,134 @@ static int msm_iommu_probe(struct platform_device *pdev)
>>   {
>>   	struct resource *r, *r2;
>>   	struct clk *iommu_clk;
>> +	struct clk *iommu_pclk;
>>   	struct msm_iommu_drvdata *drvdata;
>>   	struct msm_iommu_dev *iommu_dev = pdev->dev.platform_data;
> const please.
>

I am not clear on what you mean. Please be more specific here.

>> +	iommu_pclk = clk_get(NULL, "smmu_pclk");
>> +	if (IS_ERR(iommu_pclk)) {
>> +		ret = -ENODEV;
>> +		goto fail;
>> +	}
> I am not a big fan of this when you have the "device" around. You should just do
>
> iommu_pclk = clk_get(&pdev->dev, NULL);
>
> ...error logic...
>
> iommu_clk = clk_get(&pdev->dev, "iommu_clk");
>
> ...error logic...
>

The pclk is a "special" bus clock and does not have a specific device 
instance associated with it, so passing a device would not be 
appropriate in this case. I pass the device for other clocks that are 
indeed associated with devices, but this is not one of them. I suppose 
we could create 11 or 12 aliases for the pclk and associate it with all 
the IOMMU devices, but I would prefer to avoid doing that as I believe 
the current approach is cleaner.

>> -			ret = -EBUSY;
>> -			goto fail;
>> -		}
>> +	len = r->end - r->start + 1;
>
> resource_size please.
>

Ok