From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch-jcswGhMUV9g@public.gmane.org>
Subject: Re: [PATCH v3 2/4] soc: qcom: Add GENI based QUP Wrapper driver
Date: Thu, 8 Mar 2018 15:41:43 +0100
Message-ID: <20180308144143.GB23266@lst.de>
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To: Robin Murphy <robin.murphy-5wv7dgnIgG8@public.gmane.org>
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On Thu, Mar 08, 2018 at 01:24:45PM +0000, Robin Murphy wrote:
> Implementing dma_map_ops inside a driver for real hardware is almost always 
> the wrong thing to do.

Agreed.  dma_map_ops should be a platform decision based on the bus.

Even our dma_virt_ops basically just works around bad driver layering.