[PATCH 3.19.y-ckt 036/130] xhci: do not report PLC when link is in internal resume state

[Kamal Mostafa]

3.19.8-ckt6 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Zhuang Jin Can <jin.can.zhuang@xxxxxxxxx>

commit aca3a0489ac019b58cf32794d5362bb284cb9b94 upstream.

Port link change with port in resume state should not be
reported to usbcore, as this is an internal state to be
handled by xhci driver. Reporting PLC to usbcore may
cause usbcore clearing PLC first and port change event irq
won't be generated.

Signed-off-by: Zhuang Jin Can <jin.can.zhuang@xxxxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
 drivers/usb/host/xhci-hub.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 1cada6a..ee07ba4 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -591,7 +591,14 @@ static u32 xhci_get_port_status(struct usb_hcd *hcd,
 		status |= USB_PORT_STAT_C_RESET << 16;
 	/* USB3.0 only */
 	if (hcd->speed == HCD_USB3) {
-		if ((raw_port_status & PORT_PLC))
+		/* Port link change with port in resume state should not be
+		 * reported to usbcore, as this is an internal state to be
+		 * handled by xhci driver. Reporting PLC to usbcore may
+		 * cause usbcore clearing PLC first and port change event
+		 * irq won't be generated.
+		 */
+		if ((raw_port_status & PORT_PLC) &&
+			(raw_port_status & PORT_PLS_MASK) != XDEV_RESUME)
 			status |= USB_PORT_STAT_C_LINK_STATE << 16;
 		if ((raw_port_status & PORT_WRC))
 			status |= USB_PORT_STAT_C_BH_RESET << 16;
-- 
1.9.1

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