Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760347Ab2BJWgn (ORCPT ); Fri, 10 Feb 2012 17:36:43 -0500 Received: from ogre.sisk.pl ([217.79.144.158]:46974 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752705Ab2BJWgl (ORCPT ); Fri, 10 Feb 2012 17:36:41 -0500 From: "Rafael J. Wysocki" To: Jesse Barnes Subject: Re: [PATCH] PCI / PM: Disable wakeup during shutdown for devices not enabled to wake up Date: Fri, 10 Feb 2012 23:40:29 +0100 User-Agent: KMail/1.13.6 (Linux/3.3.0-rc2+; KDE/4.6.0; x86_64; ; ) Cc: Linux PM list , LKML , linux-pci@vger.kernel.org, Alan Stern References: <201202070050.35931.rjw@sisk.pl> <20120210123407.7087d6a4@jbarnes-desktop> In-Reply-To: <20120210123407.7087d6a4@jbarnes-desktop> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-2" Content-Transfer-Encoding: 7bit Message-Id: <201202102340.29644.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2783 Lines: 64 On Friday, February 10, 2012, Jesse Barnes wrote: > On Tue, 7 Feb 2012 00:50:35 +0100 > "Rafael J. Wysocki" wrote: > > > From: Rafael J. Wysocki > > > > If a PCI device is enabled to generate wakeup signals (PME) when put > > into a low-power state by runtime PM, it will be still enabled to > > generate those signals after the system shutdown, unless its driver's > > .shutdown() callback takes care of the wakeup signals generation > > setting. Moreover, there are devices that are not enabled to wake > > up the system and that are configured by runtime PM to generate > > wakeup signals so that (runtime) remote wakeup works with them. > > Those devices should be reconfigured during system shutdown so that > > they don't generate wakeup signals, but at least some drivers don't > > do that. However, that very well may be done by the PCI core so > > that drivers don't have to worry about it. For this reason, modify > > pci_device_shutdown() to disable the generation of wakeup events for > > devices not supposed to wake up the system. > > > > References: https://bugzilla.kernel.org/show_bug.cgi?id=37952 > > Reported-and-tested-by: Kamil Iskra > > Signed-off-by: Rafael J. Wysocki > > --- > > drivers/pci/pci-driver.c | 10 ++++++++++ > > 1 file changed, 10 insertions(+) > > > > Index: linux/drivers/pci/pci-driver.c > > =================================================================== > > --- linux.orig/drivers/pci/pci-driver.c > > +++ linux/drivers/pci/pci-driver.c > > @@ -430,6 +430,16 @@ static void pci_device_shutdown(struct d > > drv->shutdown(pci_dev); > > pci_msi_shutdown(pci_dev); > > pci_msix_shutdown(pci_dev); > > + > > + /* > > + * Devices may be enabled to wake up by runtime PM, but they need not > > + * be supposed to wake up the system from its "power off" state (e.g. > > + * ACPI S5). Therefore disable wakeup for all devices that aren't > > + * supposed to wake up the system at this point. The state argument > > + * will be ignored by pci_enable_wake(). > > + */ > > + if (!device_may_wakeup(dev)) > > + pci_enable_wake(pci_dev, PCI_UNKNOWN, false); > > } > > > > #ifdef CONFIG_PM > > > > So where do we end up setting the right wakeup state for devices we > actually *do* want to wake the system from S5? Presumably later in the > shutdown sequence? Yes, in general. However, device_may_wakeup(dev) has to return true for those devices, so they aren't affected by this change. Thanks, Rafael -- 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/