Re: [PATCH 1/4] dt-bindings: Document the STM32 DMA bindings

From: Arnd Bergmann
Date: Thu Oct 08 2015 - 16:41:08 EST


On Thursday 08 October 2015 22:25:50 M'boumba Cedric Madianga wrote:
> >
> > How do you know which channels are available for memory-to-memory
> > transfers?
> For memory-to-memory transfer we don't need any channel/request combination.
> We look for any available channel in the channel list to execute our transfer.
> So, as often as possible, we expect that a peripheral release his
> channel after transfering data.
> In that way, we always should have at least one channel available for
> that kind of transfer.
>

Ah, got it. So the use of virtual channels in this driver makes MEM2MEM
transfers work, but is otherwise not required.

Thanks for the clarification.

Arnd
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