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Date: Tue, 19 Jul 2011 13:59:27 +0530
From: viresh kumar <viresh.kumar@st.com>
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To: "Koul, Vinod" <vinod.koul@intel.com>,
        Dan Williams <dan.j.williams@intel.com>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Shiraz HASHIM <shiraz.hashim@st.com>,
        Armando VISCONTI <armando.visconti@st.com>
Subject: [Query]: What should we do in txd->tx_submit() and device_issue_pending()
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Hi Dan/Vinod,

I have one query regarding implementation of few routines in DMA drivers.

What the exact purpose of txd->tx_submit() and device_issue_pending() routines?

Should tx_submit() always start physical transfer (Obviously, if channel is free)?
Or should it just queue requests and then finally a call to device_issue_pending()
must start physical transfers?

-- 
viresh