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From: Arnd Bergmann <arnd@arndb.de>
To: Tony Lindgren <tony@atomide.com>
Subject: Re: [PATCH v7 01/10] ARM: davinci: move private EDMA API to arm/common
Date: Tue, 5 Feb 2013 22:26:30 +0000
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Cc: Felipe Balbi <balbi@ti.com>,
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On Tuesday 05 February 2013, Tony Lindgren wrote:
> * Felipe Balbi <balbi@ti.com> [130204 07:46]:
> > 
> > Current DMA abstraction is quite poor, for example there's no way to
> > compile support for multiple DMA engines. Code also makes certain, IMO
> > unnecessary, assumptions about the underlying DMA engine (abstraction is
> > poor, as said above but it we could follow MUSB's programming guide when
> > it comes to programming DMA transfers).
> > 
> > Considering all of the above, it's far better to use DMA engine and get
> > rid of all the mess.
> 
> How about just disable MUSB DMA support if ARCH_MULTIPLATFORM for now?
> That way MUSB can be fixed up first to support ARCH_MULTIPLATFORM
> using PIO while sorting out the DMA related issues.

Sounds ok to me. Someone still needs to do the work to make the non-DMA
variants of MUSB coexist in one kernel, but as we discussed erlier, that
should be much simpler.

	Arnd