From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752749AbYIXL7e (ORCPT ); Wed, 24 Sep 2008 07:59:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751437AbYIXL71 (ORCPT ); Wed, 24 Sep 2008 07:59:27 -0400 Received: from mail.atmel.fr ([81.80.104.162]:55983 "EHLO atmel-es2.atmel.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751239AbYIXL70 (ORCPT ); Wed, 24 Sep 2008 07:59:26 -0400 Message-ID: <48DA2B94.3020804@atmel.com> Date: Wed, 24 Sep 2008 13:59:16 +0200 From: Nicolas Ferre Organization: atmel User-Agent: Thunderbird 2.0.0.16 (Windows/20080708) MIME-Version: 1.0 To: maciej.sosnowski@intel.com, Linux Kernel list CC: dan.j.williams@intel.com, Haavard Skinnemoen Subject: dmaengine: DMA_CTRL_ACK flag signification Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi all, I am in the process of writing a driver for an on-chip Atmel DMA engine. I am a little confused about the use of the flag DMA_CTRL_ACK : It seems that it is set in most of the descriptors in use except the first or last of a descriptor chain. So, I cannot find where this flag is cleared. In short, I do not see what it is used for : how must I take it into account in my driver (in device_prep_dma_memcpy() for instance) ? Can you enlighten me ? Regards, -- Nicolas Ferre