From: Rafael J. Wysocki Date: Thu, 5 Jul 2012 21:20:00 +0000 (-0600) Subject: PCI / PM: restore the original behavior of pci_set_power_state() X-Git-Tag: v3.6-rc1~112^2~9^2 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=db288c9c5f9db45610dab3940377625132b4af41;p=pandora-kernel.git 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 --- Reading git-diff-tree failed