From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758650Ab2AMSN4 (ORCPT ); Fri, 13 Jan 2012 13:13:56 -0500 Received: from out3-smtp.messagingengine.com ([66.111.4.27]:44714 "EHLO out3-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752774Ab2AMSNw (ORCPT ); Fri, 13 Jan 2012 13:13:52 -0500 X-Sasl-enc: oq24I05/cMlWRHsOjjBe5dKmeJErpH46QloZdCVLBFR2 1326478431 Date: Fri, 13 Jan 2012 10:09:32 -0800 From: Greg KH To: "Gupta, Ajay Kumar" Cc: "linux-usb@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: RFC: usb: musb: Adding CPPI4.1 DMA driver under drivers/dma Message-ID: <20120113180932.GB29700@kroah.com> References: <201201120753.00667.oneukum@suse.de> <20120112215014.GC5735@xanatos> <20120112215459.GA1161@kroah.com> <20120112222947.GD5735@xanatos> <20120112223513.GA2925@kroah.com> <20120113061144.GA30569@suse.cz> <47CEF8C4B26E8C44B22B028A650E0EA9317A6B8B@DBDE01.ent.ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <47CEF8C4B26E8C44B22B028A650E0EA9317A6B8B@DBDE01.ent.ti.com> 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 On Fri, Jan 13, 2012 at 10:40:50AM +0000, Gupta, Ajay Kumar wrote: > Hi, > > CPPI4.1 (Communication Port Programming Interface) is a TI specific DMA > controller used in multiple TI platform such as AM33x, DA8x, AM35x, TI81x. > The DMA engine is mainly used by musb controller on above platform. > > Earlier version of the driver was submitted by Sergei Shtylyov at [1] but > was not merged due to disagreement on the location of driver in kernel. > Refer the discussions at [1] for more details. > > [1] http://marc.info/?l=linux-usb&m=125087318308323 > > The new implementation of the CPPI4.1 DMA slave driver will be in the > drivers/dma folder, complying to dmaengine framework. > It would involve changes in existing musb driver also for which current > plan is to maintain the compatibility of non-CPPI4.1 DMA in musb driver. > > The task is planned to be spitted into below subtasks. > > (1) Post RFC on the API details, changes envisaged in musb driver and other > challenges > > (2) Implement and post RFC for the CPPI4.1 DMA driver and changes needed in > musb driver. > > Let me know if you have any thoughts/comments on this. First off, don't highjack threads (you responded to a linux-usb thread here, get a better email client please.) Second, that sounds fine, please post patches. thanks, greg k-h