[4.2.y-ckt stable] Patch "usb: xhci: set SSIC port unused only if xhci_suspend succeeds" has been added to the 4.2.y-ckt tree

[Kamal Mostafa]

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

    usb: xhci: set SSIC port unused only if xhci_suspend succeeds

to the linux-4.2.y-queue branch of the 4.2.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-4.2.y-queue

This patch is scheduled to be released in version 4.2.8-ckt5.

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

For more information about the 4.2.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

---8<------------------------------------------------------------

>From 8efaf45f7671d315839ae7ae8ba6d94d9d3d5395 Mon Sep 17 00:00:00 2001
From: Lu Baolu <baolu.lu at linux.intel.com>
Date: Tue, 26 Jan 2016 17:50:07 +0200
Subject: usb: xhci: set SSIC port unused only if xhci_suspend succeeds

commit 92149c930cce1865d0d4aca2ab07c2b4b197b418 upstream.

XHCI_SSIC_PORT_UNUSED quirk was applied to the xHCI host controllers
in some Intel SoC chips.  With this quirk applied, SSIC port is set
to "unused" prior to xhci_suspend(). This may cause problem if host
fails to suspend.  In this case, the port is set to unused without
host further entering D3, and the port will not be usable anymore.

Signed-off-by: Zhuang Jin Can <jin.can.zhuang at intel.com>
Signed-off-by: Lu Baolu <baolu.lu at linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman at linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/usb/host/xhci-pci.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 87f33a5..9e9da66 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -369,6 +369,7 @@ static int xhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
 {
 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
 	struct pci_dev		*pdev = to_pci_dev(hcd->self.controller);
+	int			ret;

 	/*
 	 * Systems with the TI redriver that loses port status change events
@@ -383,7 +384,11 @@ static int xhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
 	if (xhci->quirks & XHCI_SSIC_PORT_UNUSED)
 		xhci_ssic_port_unused_quirk(hcd, true);

-	return xhci_suspend(xhci, do_wakeup);
+	ret = xhci_suspend(xhci, do_wakeup);
+	if (ret && (xhci->quirks & XHCI_SSIC_PORT_UNUSED))
+		xhci_ssic_port_unused_quirk(hcd, false);
+
+	return ret;
 }

 static int xhci_pci_resume(struct usb_hcd *hcd, bool hibernated)
--
2.7.0