[PATCH 3.12 25/82] xhci: do not report PLC when link is in internal resume state

[Jiri Slaby]

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

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

===============

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: Jiri Slaby <jslaby@xxxxxxx>
---
 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 4adc1be24b4a..55b3aa33bc06 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -586,7 +586,14 @@ 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;
-- 
2.5.0

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