[PATCH 3.2 099/110] xhci: do not report PLC when link is in internal resume state

[Ben Hutchings]

3.2.71-rc1 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>
[bwh: Backported to 3.2:
 - Adjust indentation
 - s/raw_port_status/temp/]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/usb/host/xhci-hub.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -595,7 +595,14 @@ int xhci_hub_control(struct usb_hcd *hcd
 			status |= USB_PORT_STAT_C_RESET << 16;
 		/* USB3.0 only */
 		if (hcd->speed == HCD_USB3) {
-			if ((temp & 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 ((temp & PORT_PLC) &&
+				(temp & PORT_PLS_MASK) != XDEV_RESUME)
 				status |= USB_PORT_STAT_C_LINK_STATE << 16;
 			if ((temp & PORT_WRC))
 				status |= USB_PORT_STAT_C_BH_RESET << 16;

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