Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756762Ab3EJO1p (ORCPT ); Fri, 10 May 2013 10:27:45 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:57281 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755989Ab3EJOWA (ORCPT ); Fri, 10 May 2013 10:22:00 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Yinghai Lu" , "Bjorn Helgaas" , "Chris J. Benenati" , "Rafael J. Wysocki" Date: Fri, 10 May 2013 14:39:41 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [033/118] PCI/PM: Fix fallback to PCI_D0 in pci_platform_power_transition() In-Reply-To: X-SA-Exim-Connect-IP: 2001:470:1f08:1539:d51a:8785:aa0a:cebe X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2308 Lines: 60 3.2.45-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: "Rafael J. Wysocki" commit 769ba7212f2059ca9fe0c73371e3d415c8c1c529 upstream. Commit b51306c (PCI: Set device power state to PCI_D0 for device without native PM support) modified pci_platform_power_transition() by adding code causing dev->current_state for devices that don't support native PCI PM but are power-manageable by the platform to be changed to PCI_D0 regardless of the value returned by the preceding platform_pci_set_power_state(). In particular, that also is done if the platform_pci_set_power_state() has been successful, which causes the correct power state of the device set by pci_update_current_state() in that case to be overwritten by PCI_D0. Fix that mistake by making the fallback to PCI_D0 only happen if the platform_pci_set_power_state() has returned an error. [bhelgaas: folded in Yinghai's simplification, added URL & stable info] Reference: http://lkml.kernel.org/r/27806FC4E5928A408B78E88BBC67A2306F466BBA@ORSMSX101.amr.corp.intel.com Reported-by: Chris J. Benenati Signed-off-by: Rafael J. Wysocki Signed-off-by: Bjorn Helgaas Acked-by: Yinghai Lu Signed-off-by: Ben Hutchings --- drivers/pci/pci.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -664,15 +664,11 @@ static int pci_platform_power_transition error = platform_pci_set_power_state(dev, state); if (!error) pci_update_current_state(dev, state); - /* Fall back to PCI_D0 if native PM is not supported */ - if (!dev->pm_cap) - dev->current_state = PCI_D0; - } else { + } else error = -ENODEV; - /* Fall back to PCI_D0 if native PM is not supported */ - if (!dev->pm_cap) - dev->current_state = PCI_D0; - } + + if (error && !dev->pm_cap) /* Fall back to PCI_D0 */ + dev->current_state = PCI_D0; return error; } -- 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/