Re: [PATCH v2 2/2] Documentation: dmaengine: Add a documentation for the dma controller API

From: Nicolas Ferre
Date: Thu Oct 09 2014 - 10:04:21 EST

On 09/10/2014 15:39, Geert Uytterhoeven :
> On Tue, Oct 7, 2014 at 4:52 PM, Maxime Ripard
> <maxime.ripard@xxxxxxxxxxxxxxxxxx> wrote:
>>>>> +These various types will also affect how the source and destination
>>>>> +addresses change over time, as DMA_SLAVE transfers will usually have
>>>>> +one of the addresses that will increment, while the other will not,
>>>>> +DMA_CYCLIC will have one address that will loop, while the other, will
>>>> s/the other,/the other/
>>>>> +not change, etc.
>>> This is a little bit vague in my opinion. And usually, it is pretty
>>> implementation specific.
>> Which is why we can't really be more precise. If you have any other
>> wording coming to your mind, I'm all for it :)
> Perhaps:
> Addresses pointing to RAM are typically incremented (or decremented) after
> each transfer. In case of a ring buffer, they may loop (DMA_CYCLIC).
> Addresses pointing to a device's register (e.g. a FIFO) are typically fixed.

+1 ;-)

Nicolas Ferre
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