commit: 769ba7212f2059ca9fe0c73371e3d415c8c1c529 From: "Rafael J. Wysocki" <rafael.j.wysocki@xxxxxxxxx> Date: Fri, 12 Apr 2013 13:58:17 +0000 Subject: PCI/PM: Fix fallback to PCI_D0 in pci_platform_power_transition() 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@xxxxxxxxxxxxxxxxxxxxxxxxxxxx Reported-by: Chris J. Benenati <chris.j.benenati@xxxxxxxxx> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Acked-by: Yinghai Lu <yinghai@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> # v3.2+ --- 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 b099e00..fc9bd81 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -646,15 +646,11 @@ 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; } -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html