Re: [PATCH] dmaengine: pxa_dma: fix the maximum requestor line

[Robert Jarzmik <robert.jarzmik@free.fr>]

Vinod Koul <vinod.koul@intel.com> writes:

> On Mon, Feb 08, 2016 at 03:18:51PM +0100, Robert Jarzmik wrote:
>> The current number of requestor lines is limited to 31. This was an
>> error of a previous commit, as this number is platform dependent, and is
>> actually :
>>  - for pxa25x: 40 requestor lines
>>  - for pxa27x: 74 requestor lines
>>  - for pxa3xx: 100 requestor lines
>> 
>> As the driver doesn't need to know the exact number, but only an
>
> and why would that be a good assumption?
Well, the driver doesn't use the exact value. Would that be 128, 1000 or 10000,
it wouldn't change its behavior. The clients either pass -1UL (ie. no flow
control) or a requestor line number.

> Btw shouldn't this data come from DT?
It can if you wish, but in this case I must amend the platform data case too, ie
mmp_dma_platdata. And this has an impact on MMP architecture. I'd rather have
the simpler approach unless you really want the exact number of requestor lines
to be passed in platform_data+DT.

Cheers.

-- 
Robert