From: Rafael J. Wysocki Date: Fri, 12 Apr 2013 13:58:17 +0000 (+0000) Subject: PCI/PM: Fix fallback to PCI_D0 in pci_platform_power_transition() X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=769ba7212f2059ca9fe0c73371e3d415c8c1c529;p=openwrt%2Fstaging%2Fblogic.git 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@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 Cc: # v3.2+ --- diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index b099e0025d2b..fc9bd81e8e3b 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; }