From mboxrd@z Thu Jan  1 00:00:00 1970
From: vinod.koul@intel.com (Koul, Vinod)
Date: Fri, 19 Aug 2011 19:19:04 +0530
Subject: [PATCH V2 6/6] spi/spi-pl022: Request/free DMA channels as and
	when required.
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References: <cover.1312965741.git.viresh.kumar@st.com>
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	<438BB0150E931F4B9CE701519A4463010871804A15@bgsmsx502.gar.corp.intel.com>
	<CABb+yY3SnqKN78U7vLbom1i00m=ThnRVQDVM_iX1TPu=+XzSNQ@mail.gmail.com>
	<20110810104025.GK1831@n2100.arm.linux.org.uk>
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To: linux-arm-kernel@lists.infradead.org
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On Tue, 2011-08-16 at 20:21 +0530, Jassi Brar wrote:
> On Tue, Aug 16, 2011 at 5:25 PM, Koul, Vinod <vinod.koul@intel.com> wrote:

> 
> > Sorry I still don't get this schema and how it can be scaled and be
> > generic enough to let it carry with various implementations.
> >
> > Can you publish your complete idea rather than bits and pieces...
> I already explained the complete idea. I don't have any implementation yet.
> Clients and dmaengine.c is easier to manage.
> But changes to >20 dmac drivers is the biggest effort - though they anyway
> need such modifications if we are to have the DMAENGINE utopia someday.
> In free time, I will modify a dmac driver or two, but it might take
> prohibitively
> long if I am expected to update possibly all the 20 dmac drivers and the backend
> platforms by
It would help if you can send RFC of changes in one driver and dmaengine
changes. I want to get the dmaengine changes understood well and be able
to deal with all scenarios we have. Without complete code its rather
hard :(
We can do these changes to other drivers over a period of time, that can
be taken over a period of time and we can manage that, this part is
easy.
>   a) Making dmac drivers platform agnostic and for re-routable ReqSig-Peri map.
>        That implies dmac drivers managing 'virtual-channel' front end
> and physical
>        channel and ReqSig->Peri link management in the backend with
> help from platform.
>   b) Modifying platforms/boards to pass channel map and link re-routing callback
>       pointers to generic dmac drivers.


-- 
~Vinod