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Date: Thu, 13 Aug 2015 19:55:41 +0200
From: Christoph Hellwig <hch@lst.de>
To: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>, akpm@linux-foundation.org,
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Subject: Re: [PATCH 2/5] dma-mapping: consolidate dma_{alloc,free}_noncoherent
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On Thu, Aug 13, 2015 at 04:20:40PM +0100, Russell King - ARM Linux wrote:
> > -/*
> > - * Dummy noncoherent implementation.  We don't provide a dma_cache_sync
> > - * function so drivers using this API are highlighted with build warnings.
> > - */
> 
> I'd like a similar comment to remain after this patch explaining that we
> don't support non-coherent allocations and that it'll be highlighted by
> the lack of dma_cache_sync, otherwise I'm sure we'll start to get patches
> to add the thing.

I'll keep a modified version of this comment in the ARM dma-mapping.h
in addition to an explanation near the new common dma_alloc_noncoherent
definition, thanks!