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From: "yitian" <yitian.bu@tangramtek.com>
To: "'Andy Shevchenko'" <andy.shevchenko@gmail.com>,
        "'Viresh Kumar'" <viresh.kumar@linaro.org>
Cc: "'Viresh Kumar'" <vireshk@kernel.org>,
        "'Andy Shevchenko'" <andriy.shevchenko@linux.intel.com>,
        "'Vinod Koul'" <vinod.koul@intel.com>,
        "'Dan Williams'" <dan.j.williams@intel.com>,
        "'dmaengine'" <dmaengine@vger.kernel.org>,
        "'Linux Kernel Mailing List'" <linux-kernel@vger.kernel.org>
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Subject: RE: [PATCH 1/1] dmaengine: dw: resolve recursion lock when audio playback
Date: Mon, 28 Sep 2015 15:23:20 +0800
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> From: Andy Shevchenko [mailto:andy.shevchenko@gmail.com]
> Sent: Monday, September 28, 2015 3:06 PM
> To: Viresh Kumar <viresh.kumar@linaro.org>
> Cc: yitian <yitian.bu@tangramtek.com>; Viresh Kumar
> <vireshk@kernel.org>; Andy Shevchenko
> <andriy.shevchenko@linux.intel.com>; Vinod Koul <vinod.koul@intel.com>;
> Dan Williams <dan.j.williams@intel.com>; dmaengine
> <dmaengine@vger.kernel.org>; Linux Kernel Mailing List
> <linux-kernel@vger.kernel.org>
> Subject: Re: [PATCH 1/1] dmaengine: dw: resolve recursion 
> > I am not sure if this is a sane way of doing that, and we were scanning
> > the descriptors for some valid reason..
> 
> Actually one of the patches in a pile sitting in my private repo is
> also including similar change. In my case the reason is to support
> cyclic transfers natively.
> 

Yes, i am using DW DMAC to support cyclic transfer.
Currently it is very easy to get recursion lock crash, but
after this patch everything is fine on my device.
I am waiting for your further guide.
Thanks.