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Subject: Re: [PATCH/RFC] dmaengine: add a slave parameter to
 __dma_request_channel()
From: Vinod Koul <vinod.koul@linux.intel.com>
To: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>,
        linux-kernel@vger.kernel.org,
        "'Jassi Brar'" <jassisinghbrar@gmail.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        Magnus Damm <magnus.damm@gmail.com>, Paul Mundt <lethal@linux-sh.org>
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Date: Tue, 20 Mar 2012 12:41:33 +0530
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On Mon, 2012-03-19 at 17:32 +0100, Guennadi Liakhovetski wrote:
> Sure. In the datasheet we have: to configure a channel for client 1 write 
> value X to register A and value Y to register B. That's it. One of them is 
> really just a magic slave ID. Another one has several fields with values 
> like bus width and transfer size. They could be passed "properly," but 
> since those fields also vary between DMAC versions, it is easier to just 
> fix the whole register value per client and pass it from the platform 
> data. In any case, at least the slave ID is really just a constant, that 
> cannot be calculated and has to be passed from platform data.
I think I like the idea of having the these slave IDs coming from
platform map. That way drivers can be agnostic...

-- 
~Vinod