From mboxrd@z Thu Jan  1 00:00:00 1970
From: Vinod Koul <vkoul@infradead.org>
Subject: Re: [RFC PATCH 1/3] dmaengine: add dma_get_channel_caps()
Date: Wed, 24 Oct 2012 08:39:01 +0530
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To: Dan Williams <djbw@fb.com>
Cc: vinod.koul@intel.com, Matt Porter <mporter@ti.com>, Chris Ball <cjb@laptop.org>, Linux DaVinci Kernel List <davinci-linux-open-source@linux.davincidsp.com>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, Linux MMC List <linux-mmc@vger.kernel.org>

On Tue, 2012-10-23 at 15:54 -0700, Dan Williams wrote:
> > +struct dmaengine_chan_caps {
> > +       enum dmaengine_apis ops;
> > +       int seg_nr;
> > +       int seg_len;
> > +};
> 
> This makes sense for the potentially dynamic capability properties
> that get set after configuration, but why do we need the operation
> types here?  They can be retrieved from the parent device. 
I was thinking that each channel can have different capabilities.
You can assign one channel for mempcy operations exclusively and some
others for slave usage exclusively.
I believe some h/w do have such assignment so would help in doing that.

-- 
Vinod Koul
Intel Corp.