From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759428Ab3EGNmR (ORCPT ); Tue, 7 May 2013 09:42:17 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:42496 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933286Ab3EGNmD (ORCPT ); Tue, 7 May 2013 09:42:03 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: "Rafael J. Wysocki" , Bjorn Helgaas , Luis Henriques Subject: [PATCH 088/118] PCI/PM: Fix fallback to PCI_D0 in pci_platform_power_transition() Date: Tue, 7 May 2013 14:38:54 +0100 Message-Id: <1367933964-1564-89-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1367933964-1564-1-git-send-email-luis.henriques@canonical.com> References: <1367933964-1564-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.5.7.12 -stable 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: Luis Henriques --- drivers/pci/pci.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 447e834..fa7c0f0 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -674,15 +674,11 @@ static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state) 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; } -- 1.8.1.2