Patch "xhci: Add spurious wakeup quirk for LynxPoint-LP controllers" has been added to the 4.2-stable tree

This is a note to let you know that I've just added the patch titled

xhci: Add spurious wakeup quirk for LynxPoint-LP controllers

to the 4.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
xhci-add-spurious-wakeup-quirk-for-lynxpoint-lp-controllers.patch
and it can be found in the queue-4.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Laura Abbott <[email protected]>
Date: Mon, 12 Oct 2015 11:30:13 +0300
Subject: xhci: Add spurious wakeup quirk for LynxPoint-LP controllers

From: Laura Abbott <[email protected]>

commit fd7cd061adcf5f7503515ba52b6a724642a839c8 upstream.

We received several reports of systems rebooting and powering on after an attempted shutdown. Testing showed that setting XHCI_SPURIOUS_WAKEUP quirk in addition to the XHCI_SPURIOUS_REBOOT quirk allowed the system to shutdown as expected for LynxPoint-LP xHCI controllers. Set the quirk back.

Note that the quirk was originally introduced for LynxPoint and LynxPoint-LP just for this same reason. See:

commit 638298dc66ea ("xhci: Fix spurious wakeups after S5 on Haswell")

It was later limited to only concern HP machines as it caused regression on some machines, see both bug and commit:

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=66171
commit 6962d914f317 ("xhci: Limit the spurious wakeup fix only to HP machines")

Later it was discovered that the powering on after shutdown was limited to LynxPoint-LP (Haswell-ULT) and that some non-LP HP machine suffered from spontaneous resume from S3 (which should not be related to the SPURIOUS_WAKEUP quirk at all). An attempt to fix this then removed the SPURIOUS_WAKEUP flag usage completely.

commit b45abacde3d5 ("xhci: no switching back on non-ULT Haswell")

Current understanding is that LynxPoint-LP (Haswell ULT) machines need the SPURIOUS_WAKEUP quirk, otherwise they will restart, and plain Lynxpoint (Haswell) machines may _not_ have the quirk set otherwise they again will restart.

---
 drivers/usb/host/xhci-pci.c |    1 +
 1 file changed, 1 insertion(+)

@@ -147,6 +147,7 @@ static void xhci_pci_quirks(struct devic
 	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
 		pdev->device == PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_XHCI) {
 		xhci->quirks |= XHCI_SPURIOUS_REBOOT;
+		xhci->quirks |= XHCI_SPURIOUS_WAKEUP;
 	}
 	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
 		(pdev->device == PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_XHCI ||

Patches currently in stable-queue which might be from [email protected] are

queue-4.2/si2157-bounds-check-firmware.patch queue-4.2/xhci-add-spurious-wakeup-quirk-for-lynxpoint-lp-controllers.patch queue-4.2/si2168-bounds-check-firmware.patch