Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932154Ab1EZM7E (ORCPT ); Thu, 26 May 2011 08:59:04 -0400 Received: from mga02.intel.com ([134.134.136.20]:5658 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753277Ab1EZM7C (ORCPT ); Thu, 26 May 2011 08:59:02 -0400 X-ExtLoop1: 1 Subject: Re: [PATCH 2/2] dmaengine: add TODO items for future work on dma drivers From: "Koul, Vinod" To: Russell King - ARM Linux Cc: LKML , "linux-arm-kernel@lists.infradead.org" , Linus Walleij , "Williams, Dan J" , Per Forlin In-Reply-To: <20110526073620.GF24876@n2100.arm.linux.org.uk> References: <1306323570-11133-1-git-send-email-vinod.koul@intel.com> <1306323570-11133-3-git-send-email-vinod.koul@intel.com> <20110526073620.GF24876@n2100.arm.linux.org.uk> Content-Type: text/plain; charset="UTF-8" Date: Thu, 26 May 2011 17:55:30 +0530 Message-ID: <1306412730.2230.0.camel@vkoul-udesk3> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1534 Lines: 40 On Thu, 2011-05-26 at 13:06 +0530, Russell King - ARM Linux wrote: > On Wed, May 25, 2011 at 05:09:30PM +0530, Koul, Vinod wrote: > > +1. Move remaining drivers to use new slave interface > > +2. Remove old slave pointer machansim > > +3. Make issue_pending to start the transaction in below drivers > > + - mpc512x_dma > > + - imx-dma > > + - imx-sdma > > + - mxs-dma.c > > + - dw_dmac > > + - intel_mid_dma > > + - ste_dma40 > > I'd suggest adding some more to this: > > 4. Remove dma_slave_config's dma direction. > > It's pointless that dma_slave_config carries the DMA direction (to/from > device) and the prepare function does too. It leads to DMA engine drivers > having to verify that the two match, and DMA engine users having to issue > two calls every time they change direction. > > Instead, lets specify that dma_slave_config carries the _device_ side > parameters, which are selected according to the direction given to the > prepare function. The memory-side parameters should be selected by the > DMA engine driver according to its knowledge of the system. > > This is sensible as M2M transfers don't allow configuration and therefore > already have to select these parameters internally. Sure, I am adding this as well and applying both patches Thanks -- ~Vinod -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/