From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andy Gross <agross@codeaurora.org>
Subject: Re: [PATCH] spi: qup: Add DMA capabilities
Date: Fri, 27 Jun 2014 10:54:22 -0500
Message-ID: <20140627155422.GA13621@qualcomm.com>
References: <1403816781-31008-1-git-send-email-agross@codeaurora.org>
 <20140627105057.GF23300@sirena.org.uk>
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Cc: linux-spi@vger.kernel.org, Sagar Dharia <sdharia@codeaurora.org>,
	Daniel Sneddon <dsneddon@codeaurora.org>,
	Bjorn Andersson <bjorn.andersson@sonymobile.com>,
	"Ivan T. Ivanov" <iivanov@mm-sol.com>,
	linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-arm-msm@vger.kernel.org
To: Mark Brown <broonie@kernel.org>
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On Fri, Jun 27, 2014 at 11:50:57AM +0100, Mark Brown wrote:
> On Thu, Jun 26, 2014 at 04:06:21PM -0500, Andy Gross wrote:
> 
> > +	if (xfer->rx_buf) {
> > +		rx_dma = dma_map_single(controller->dev, xfer->rx_buf,
> > +			xfer->len, DMA_FROM_DEVICE);
> 
> It would be better to use the core DMA mapping code rather than open
> coding.  This code won't work for vmalloc()ed addresses, or physically
> non-contiguous addresses unless there's an IOMMU fixing things up.

Ah, ok.  So I just need a to setup the scatter gather page list and then do a
dma_map_sg.  I'll resend once I have this in place.


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