From db288c9c5f9db45610dab3940377625132b4af41 Mon Sep 17 00:00:00 2001 From: Rafael J. Wysocki Date: Thu, 5 Jul 2012 15:20:00 -0600 Subject: PCI / PM: restore the original behavior of pci_set_power_state() Commit cc2893b6 (PCI: Ensure we re-enable devices on resume) addressed the problem with USB not being powered after resume on recent Lenovo machines, but it did that in a suboptimal way. Namely, it should have changed the relevant code paths only, which are pci_pm_resume_noirq() and pci_pm_restore_noirq() supposed to restore the device's power and standard configuration registers after system resume from suspend or hibernation. Instead, however, it modified pci_set_power_state() which is executed in several other situations too. That resulted in some undesirable effects, like attempting to change a device's power state in the same way multiple times in a row (up to as many as 4 times in a row in the snd_hda_intel driver). Fix the bug addressed by commit cc2893b6 in an alternative way, by forcibly powering up all devices in pci_pm_default_resume_early(), which is called by pci_pm_resume_noirq() and pci_pm_restore_noirq() to restore the device's power and standard configuration registers, and modifying pci_pm_runtime_resume() to avoid the forcible power-up if not necessary. Then, revert the changes made by commit cc2893b6 to make the confusion introduced by it go away. Acked-by: Matthew Garrett Signed-off-by: Rafael J. Wysocki Signed-off-by: Bjorn Helgaas --- drivers/pci/pci.h | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/pci/pci.h') diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 5cd3dce7a245..331857855eb4 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -67,6 +67,7 @@ struct pci_platform_pm_ops { extern int pci_set_platform_pm(struct pci_platform_pm_ops *ops); extern void pci_update_current_state(struct pci_dev *dev, pci_power_t state); +extern void pci_power_up(struct pci_dev *dev); extern void pci_disable_enabled_device(struct pci_dev *dev); extern int pci_finish_runtime_suspend(struct pci_dev *dev); extern int __pci_pme_wakeup(struct pci_dev *dev, void *ign); -- cgit v1.2.3-55-g7522