[ 3.8.y.z extended stable ] Patch "PCI / ACPI / PM: Clear pme_poll for devices in D3cold on wakeup" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    PCI / ACPI / PM: Clear pme_poll for devices in D3cold on wakeup

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.11.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 11b88fc9801e408c68febe3ced13915410da1667 Mon Sep 17 00:00:00 2001
From: "Rafael J. Wysocki" <rafael.j.wysocki at intel.com>
Date: Sat, 14 Sep 2013 03:38:20 +0200
Subject: PCI / ACPI / PM: Clear pme_poll for devices in D3cold on wakeup

commit 834145156bedadfb50121f0bc5e9d9f9f942bcca upstream.

Commit 448bd85 (PCI/PM: add PCIe runtime D3cold support) added a
piece of code to pci_acpi_wake_dev() causing that function to behave
in a special way for devices in D3cold (so that their configuration
registers are not accessed before those devices are resumed).
However, it didn't take the clearing of the pme_poll flag into
account.  That has to be done for all devices, even if they are in
D3cold, or pci_pme_list_scan() will not know that wakeup has been
signaled for the device and will poll its PME Status bit
unnecessarily.

Fix the problem by moving the clearing of the pme_poll flag in
pci_acpi_wake_dev() before the code introduced by commit 448bd85.

Reported-and-tested-by: David E. Box <david.e.box at intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki at intel.com>
Acked-by: Bjorn Helgaas <bhelgaas at google.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/pci/pci-acpi.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index 21354bf..e1e3d1b 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -47,6 +47,9 @@ static void pci_acpi_wake_dev(acpi_handle handle, u32 event, void *context)
 	if (event != ACPI_NOTIFY_DEVICE_WAKE || !pci_dev)
 		return;

+	if (pci_dev->pme_poll)
+		pci_dev->pme_poll = false;
+
 	if (pci_dev->current_state == PCI_D3cold) {
 		pci_wakeup_event(pci_dev);
 		pm_runtime_resume(&pci_dev->dev);
@@ -57,9 +60,6 @@ static void pci_acpi_wake_dev(acpi_handle handle, u32 event, void *context)
 	if (pci_dev->pme_support)
 		pci_check_pme_status(pci_dev);

-	if (pci_dev->pme_poll)
-		pci_dev->pme_poll = false;
-
 	pci_wakeup_event(pci_dev);
 	pm_runtime_resume(&pci_dev->dev);

--
1.8.1.2