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From: Arnd Bergmann <arnd@arndb.de>
To: Matt Porter <mporter@ti.com>
Subject: Re: [PATCH v4 00/14] DMA Engine support for AM33XX
Date: Fri, 11 Jan 2013 11:40:41 +0000
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On Friday 11 January 2013, Matt Porter wrote:
> The approach taken is similar to how OMAP DMA is being converted to
> DMA Engine support. With the functional EDMA private API already
> existing in mach-davinci/dma.c, we first move that to an ARM common
> area so it can be shared. Adding DT and runtime PM support to the
> private EDMA API implementation allows it to run on AM33xx. AM33xx
> only boots using DT so we leverage Jon's generic DT DMA helpers to
> register EDMA DMAC with the of_dma framework and then add support
> for calling the dma_request_slave_channel() API to both the mmc
> and spi drivers.

I think this looks very good. What I wonder is whether we should
make the non-DT parts of the dmaengine driver compile-time
conditional on CONFIG_ATAGS though, so the slave drivers don't
have a link-time dependency on the dmaengine driver's 
omap_dma_filter_fn symbol when building without ATAGS support.

	Arnd