Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932265Ab1DYVYm (ORCPT ); Mon, 25 Apr 2011 17:24:42 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:48118 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1755314Ab1DYVYh (ORCPT ); Mon, 25 Apr 2011 17:24:37 -0400 Date: Mon, 25 Apr 2011 17:24:34 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Willy Tarreau cc: Kernel development list , , , Greg Kroah-Hartman Subject: Re: [PATCH 039/173] OHCI: work around for nVidia shutdown problem In-Reply-To: <20110425200234.685881927@pcw.home.local> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2211 Lines: 49 On Mon, 25 Apr 2011, Willy Tarreau wrote: > 2.6.27.59-stable review patch. If anyone has any objections, please let us know. > > ------------------ > > From: Alan Stern > > commit 3df7169e73fc1d71a39cffeacc969f6840cdf52b upstream. > > This patch (as1417) fixes a problem affecting some (or all) nVidia > chipsets. When the computer is shut down, the OHCI controllers > continue to power the USB buses and evidently they drive a Reset > signal out all their ports. This prevents attached devices from going > to low power. Mouse LEDs stay on, for example, which is disconcerting > for users and a drain on laptop batteries. > > The fix involves leaving each OHCI controller in the OPERATIONAL state > during system shutdown rather than putting it in the RESET state. > Although this nominally means the controller is running, in fact it's > not doing very much since all the schedules are all disabled. However > there is ongoing DMA to the Host Controller Communications Area, so > the patch also disables the bus-master capability of all PCI USB > controllers after the shutdown routine runs. > > The fix is applied only to nVidia-based PCI OHCI controllers, so it > shouldn't cause problems on systems using other hardware. As an added > safety measure, in case the kernel encounters one of these running > controllers during boot, the patch changes quirk_usb_handoff_ohci() > (which runs early on during PCI discovery) to reset the controller > before anything bad can happen. > > Reported-by: Pali Rohár > Signed-off-by: Alan Stern > CC: David Brownell > Tested-by: Pali Rohár > Signed-off-by: Greg Kroah-Hartman Some people have reported that more recent Nvidia systems work correctly without this patch and have problems when the patch is applied. For now, I suggest omitting this patch. Alan Stern -- 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/