From mboxrd@z Thu Jan  1 00:00:00 1970
From: Arnd Bergmann <arnd@arndb.de>
Date: Fri, 31 May 2013 16:02:31 +0000
Subject: Re: [PATCH 1/2] ARM: shmobile: sdhi: pass DMA filter from platform code
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To: linux-arm-kernel@lists.infradead.org

On Friday 31 May 2013 17:30:01 Guennadi Liakhovetski wrote:
> On Fri, 31 May 2013, Arnd Bergmann wrote:
> > On Friday 31 May 2013 16:52:13 Guennadi Liakhovetski wrote:

> > I think it's more a matter of using the API correctly. The dmaengine
> > API is an abstraction to separate the slave driver from the master
> > through well-defined calls. If you make additional assumptions
> > in the slave driver about the master, that is a layering violation.
> 
> I think it is a common practice, see e.g.
> 
> drivers/mmc/host/omap_hsmmc.c
> drivers/mmc/host/davinci_mmc.c

Yes, those should be fixed as well.

> And what do you do for DT-based platforms?

Once the driver is DT-enabled, we no longer have to pass
a filter function at all because the slave id and all settings
will get pulled out of the DT using the dma engine's xlate()
callback.

	Arnd