From mboxrd@z Thu Jan  1 00:00:00 1970
From: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
Subject: Re: [PATCH v5 07/14] dmaengine: add dma_request_slave_channel_compat()
Date: Mon, 28 Jan 2013 19:57:47 +0000
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To: Andy Shevchenko <andy.shevchenko-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: Matt Porter <mporter-l0cyMroinI0@public.gmane.org>, Linux DaVinci Kernel List <davinci-linux-open-source-VycZQUHpC/PFrsHnngEfi1aTQe2KTcn/@public.gmane.org>, Linux OMAP List <linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>, Linux Documentation List <linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Linux MMC List <linux-mmc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Devicetree Discuss <devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org>, Mark Brown <broonie-yzvPICuk2AATkU/dhu1WVueM+bqZidxxQQ4Iyu8u01E@public.gmane.org>, Sekhar Nori <nsekhar-l0cyMroinI0@public.gmane.org>, Linux Kernel Mailing List <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Rob Herring <rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org>, Vinod Koul <vinod.koul-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>, Dan Williams <djbw-b10kYP2dOMg@public.gmane.org>, Linux SPI Devel List <spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org>, Chris Ball <cjb-2X9k7bc8m7Mdnm+yROfE0A@public.gmane.org>, Linux ARM Kernel List <linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org>
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On Monday 28 January 2013, Andy Shevchenko wrote:
> On Tue, Jan 15, 2013 at 10:32 PM, Matt Porter <mporter-l0cyMroinI0@public.gmane.org> wrote:
> > Adds a dma_request_slave_channel_compat() wrapper which accepts
> > both the arguments from dma_request_channel() and
> > dma_request_slave_channel(). Based on whether the driver is
> > instantiated via DT, the appropriate channel request call will be
> > made.
> >
> > This allows for a much cleaner migration of drivers to the
> > dmaengine DT API as platforms continue to be mixed between those
> > that boot using DT and those that do not.
> 
> Does it mean the introduced function is kinda temporary?

Some drivers can very likely get converted to use only
dma_request_slave_channel() in the long run, when all
the platforms using those drivers have been converted to
provide the channels using device tree.

However, for drivers that are used on legacy platforms
without DT support, we may still need something like
this function in the long run.

	Arnd