From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from an-out-0708.google.com (an-out-0708.google.com [209.85.132.241]) by ozlabs.org (Postfix) with ESMTP id 8D9CFDDE2E for ; Thu, 12 Jul 2007 02:56:33 +1000 (EST) Received: by an-out-0708.google.com with SMTP id c37so309663anc for ; Wed, 11 Jul 2007 09:56:32 -0700 (PDT) Message-ID: Date: Wed, 11 Jul 2007 09:56:31 -0700 From: "Dan Williams" Sender: dan.j.williams@gmail.com To: "Zhang Wei-r63237" Subject: Re: [PATCH 3/4] Extend the DMA-engine API. In-Reply-To: <46B96294322F7D458F9648B60E15112C6F3CED@zch01exm26.fsl.freescale.net> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed References: <11840607111926-git-send-email-wei.zhang@freescale.com> <46B96294322F7D458F9648B60E15112C6F3CED@zch01exm26.fsl.freescale.net> Cc: shannon.nelson@intel.com, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, paulus@samba.org, akpm@linux-foundation.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 7/11/07, Zhang Wei-r63237 wrote: > Hi, Dan, > > Do you mention here: http://marc.info/?l=linux-raid&m=118290909614463&w=2 ? > I see the async_tx is located at crypto/ of the above page, but my patch is for DMA engine in drivers/dma and for DMA engine driver. > > Thanks! > Wei. Hi Wei, I was referring to: http://marc.info/?l=linux-raid&m=118290909528910&w=2 async_tx is an api that exploits the raw capabilities of the new dmaengine interface. For your case when the existing api calls do not provide the proper interface you can open code something like the following: tx = dev->device_prep_dma_(chan, len, int_flag) tx->tx_set_src(dma_addr_t, tx, index /* for multi-source ops */) tx->tx_set_dest(dma_addr_t, tx, index) tx->tx_submit(tx) The expectation is that the most common usages of dmaengines will use async_tx calls, or the 'dma_async_memcpy_foo_to_bar' helper routines. -- Dan