Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752447AbcDZQWR (ORCPT ); Tue, 26 Apr 2016 12:22:17 -0400 Received: from mga09.intel.com ([134.134.136.24]:8041 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751317AbcDZQWP (ORCPT ); Tue, 26 Apr 2016 12:22:15 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.24,537,1455004800"; d="scan'208";a="940622253" Date: Tue, 26 Apr 2016 21:58:07 +0530 From: Vinod Koul To: Andy Shevchenko Cc: Ramon Fried , "dan.j.williams@intel.com" , "dmaengine@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: dmatest - scatter gather mode Message-ID: <20160426162807.GL2274@localhost> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 840 Lines: 19 On Tue, Apr 26, 2016 at 05:37:04PM +0300, Andy Shevchenko wrote: > On Sun, Apr 24, 2016 at 9:44 PM, Ramon Fried wrote: > > I'm looking of a way to validate a DMA engine driver I've written. > > I came across dmatest module and while reading the code I've noticed that scatter-gather DMA mode is not implemented. > > I wonder if anyone one knows the reason, and if such enhancement will be welcome as a patch. > > You meant the actual slave interaction? How can you implement this in > a generic way? > For example we are using an SPI controller in loopback mode to check DMA driver. > In your case it might be something really specific. > > Otherwise you may try mem copy functionality if your DMA engine supports such. I think he means dma copy using sg lists, see the patch posted today for that -- ~Vinod