From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755789Ab2A0PKB (ORCPT ); Fri, 27 Jan 2012 10:10:01 -0500 Received: from mail-bk0-f46.google.com ([209.85.214.46]:45583 "EHLO mail-bk0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752628Ab2A0PKA (ORCPT ); Fri, 27 Jan 2012 10:10:00 -0500 Message-ID: <4F22CC37.8010307@mvista.com> Date: Fri, 27 Jan 2012 19:09:27 +0300 From: Sergei Shtylyov User-Agent: Mozilla/5.0 (X11; Linux i686; rv:6.0) Gecko/20110812 Thunderbird/6.0 MIME-Version: 1.0 To: "Gupta, Ajay Kumar" CC: "linux-usb@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "Pasupathy, Visuvanadan" , "Balbi, Felipe" Subject: Re: RFC: usb: musb: Changes proposed for adding CPPI4.1 DMA References: <47CEF8C4B26E8C44B22B028A650E0EA9317C5B92@DBDE01.ent.ti.com> In-Reply-To: <47CEF8C4B26E8C44B22B028A650E0EA9317C5B92@DBDE01.ent.ti.com> 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 Hello. On 01/25/2012 06:22 PM, Gupta, Ajay Kumar wrote: > As a next step to dma-engine based cppi4.1 driver implementation > this RFC has the overview of changes in the musb driver. > RFC on CPPI slave driver changes will follow next. > Overview of changes in the musb driver > ====================================== > 1)Add a dma-engine.c file in the drivers/usb/musb folder > 2)This file will host the current musb dma APIs and translates them to > dmaengine APIs. > 3)This will help to keep the changes in drivers/usb/musb/musb* files > minimal and also to retain compatibility other DMA (Mentor etc.) > drivers which are yet to be moved to drivers/dma > 4)drivers/usb/musb/dma-engine.c, will wrap the dmaengine APIs to > make existing musb APIs compatible. > 5)drivers/usb/musb/dma-engine.c file will implement the filter > functions and also implement .dma_controller_create (allocates > & provides "dma_controller" object) and .dma_controller_delete > 6)CPPI4.1 DMA specific queue and buffer management will be internal > to slave CPPI DMA driver implementation. You mean drivers/dma/ driver? I think you are forgotting that CPPI 4.1 MUSB has some registers controlling DMA/interrupts beside those of CPPI 4.1 controller and MUSB core itself. How do they fit in your scheme? WBR, Sergei