[PATCH 4/5] xhci: clear root port wake on bits if controller isn't wake-up capable

Mathias Nyman
2014-06-24T14:14:43Z

From: Lu Baolu <baolu.lu@linux.intel.com>

When xHCI PCI host is suspended, if do_wakeup is false in xhci_pci_suspend,
xhci_bus_suspend needs to clear all root port wake on bits. Otherwise some Intel
platforms may get a spurious wakeup, even if PCI PME# is disabled.

This patch should be back-ported to kernels as old as 2.6.37, that
contains the commit 9777e3ce907d4cb5a513902a87ecd03b52499569
"USB: xHCI: bus power management implementation".

Cc: stable@vger.kernel.org # 2.6.37
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
---
drivers/usb/host/xhci-hub.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 2b998c6..aa79e87 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -22,6 +22,7 @@

#include <linux/slab.h>
+#include <linux/device.h>
#include <asm/unaligned.h>

#include "xhci.h"
@@ -1139,7 +1140,9 @@ int xhci_bus_suspend(struct usb_hcd *hcd)
* including the USB 3.0 roothub, but only if CONFIG_PM_RUNTIME
* is enabled, so also enable remote wake here.
*/
- if (hcd->self.root_hub->do_remote_wakeup) {
+ if (hcd->self.root_hub->do_remote_wakeup
+ && device_may_wakeup(hcd->self.controller)) {
+
if (t1 & PORT_CONNECT) {
t2 |= PORT_WKOC_E | PORT_WKDISC_E;
t2 &= ~PORT_WKCONN_E;
--
1.8.3.2