Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261686AbVDZRYP (ORCPT ); Tue, 26 Apr 2005 13:24:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261695AbVDZRWg (ORCPT ); Tue, 26 Apr 2005 13:22:36 -0400 Received: from viper.oldcity.dca.net ([216.158.38.4]:53966 "HELO viper.oldcity.dca.net") by vger.kernel.org with SMTP id S261686AbVDZRTu (ORCPT ); Tue, 26 Apr 2005 13:19:50 -0400 Subject: Re: [PATCH] PCI: Add pci shutdown ability From: Lee Revell To: Alan Stern Cc: Grant Grundler , "Richard B. Johnson" , Alexander Nyberg , Greg KH , Amit Gud , linux-kernel@vger.kernel.org, linux-pci@atrey.karlin.mff.cuni.cz, akpm@osdl.org, jgarzik@pobox.com, cramerj@intel.com, USB development list In-Reply-To: References: Content-Type: text/plain Date: Tue, 26 Apr 2005 13:19:48 -0400 Message-Id: <1114535988.5410.4.camel@mindpipe> Mime-Version: 1.0 X-Mailer: Evolution 2.2.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 852 Lines: 23 On Tue, 2005-04-26 at 13:12 -0400, Alan Stern wrote: > On Tue, 26 Apr 2005, Grant Grundler wrote: > > > On Tue, Apr 26, 2005 at 12:07:41PM -0400, Richard B. Johnson wrote: > > > DMAs don't go on "forever" > > > > They don't. But we also don't know when they will stop. > > E.g. NICs will stop DMA when the RX descriptor ring is full. > > I don't know when USB stop on it's own. > > USB doesn't stop DMA on its own. It goes on forever until it's told to > stop or it encounters an error. Ditto sound cards. Once you start capture or playback the device will DMA to/from the assigned area forever. Lee - 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/