diff options
| author | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-04-12 17:58:17 +0400 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2013-04-16 00:15:43 +0400 |
| commit | 769ba7212f2059ca9fe0c73371e3d415c8c1c529 (patch) | |
| tree | 9a7e255336a71d79347bd5dceb67077570c6549f | |
| parent | f6161aa153581da4a3867a2d1a7caf4be19b6ec9 (diff) | |
| download | linux-769ba7212f2059ca9fe0c73371e3d415c8c1c529.tar.xz | |
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 <chris.j.benenati@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Cc: <stable@vger.kernel.org> # v3.2+
| -rw-r--r-- | drivers/pci/pci.c | 12 |
1 files changed, 4 insertions, 8 deletions
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; } |