From d438aa223e931bfb74dd459bb6c7f3139c48b528 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 12 Jun 2017 22:49:40 +0200 Subject: [PATCH] USB / PCI / PM: Allow the PCI core to do the resume cleanup hcd_pci_resume_noirq() used as a universal _resume_noirq handler for PCI USB controllers calls pci_back_from_sleep() which is unnecessary and may become problematic. It is unnecessary, because the PCI bus type carries out post-suspend cleanup of all PCI devices during resume and that covers all things done by the pci_back_from_sleep(). There is no reason why USB cannot follow all of the other PCI devices in that respect. It will become problematic after subsequent changes that make it possible to go back to sleep again after executing dpm_resume_noirq() if no valid system wakeup events have been detected at that point. Namely, calling pci_back_from_sleep() at the _resume_noirq stage will cause the wakeup status of the devices in question to be cleared and if any of them has triggered system wakeup, that event may be missed then. For the above reasons, drop the pci_back_from_sleep() invocation from hcd_pci_resume_noirq(). Signed-off-by: Rafael J. Wysocki Acked-by: Alan Stern Acked-by: Greg Kroah-Hartman --- drivers/usb/core/hcd-pci.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c index 7859d738df41..ea829ad798c0 100644 --- a/drivers/usb/core/hcd-pci.c +++ b/drivers/usb/core/hcd-pci.c @@ -584,12 +584,7 @@ static int hcd_pci_suspend_noirq(struct device *dev) static int hcd_pci_resume_noirq(struct device *dev) { - struct pci_dev *pci_dev = to_pci_dev(dev); - - powermac_set_asic(pci_dev, 1); - - /* Go back to D0 and disable remote wakeup */ - pci_back_from_sleep(pci_dev); + powermac_set_asic(to_pci_dev(dev), 1); return 0; }