When a PCI bridge is runtime resumed from D3cold the underlying bus is walked and the attached devices are runtime resumed as well. However, in addition to that we also generate a wakeup event for these devices even though this actually is not a real wakeup event coming from the hardware. Normally this does not cause problems but when combined with /sys/power/wakeup_count like using the steps below: # count=$(cat /sys/power/wakeup_count) # echo $count > /sys/power/wakeup_count # echo mem > /sys/power/state The system suspend cycle might fail at this point if a PCI bridge that was runtime suspended (D3cold) was runtime resumed for any reason. The runtime resume calls pci_wakeup_bus() and that generates wakeup event increasing wakeup_count. Since this is not a real wakeup event we can prevent the above from happening by removing the call to pci_wakeup_event() in pci_wakeup_bus(). Reported-by: Utkarsh Patel <utkarsh.h.patel@xxxxxxxxx> Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> --- Previous version can be found here: https://www.spinics.net/lists/linux-pci/msg101083.html Changes from the previous version: - Split the patch in two. The second patch only does the rename. - Tried to improve the commit message a bit - Added Rafael's reviewed-by tag drivers/pci/pci.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index e578d34095e9..6f7b33998fbe 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1181,7 +1181,6 @@ EXPORT_SYMBOL_GPL(pci_platform_power_transition); */ static int pci_wakeup(struct pci_dev *pci_dev, void *ign) { - pci_wakeup_event(pci_dev); pm_request_resume(&pci_dev->dev); return 0; } -- 2.29.2
