xhci: do not report PLC when link is in internal resume state
authorZhuang Jin Can <jin.can.zhuang@intel.com>
Tue, 21 Jul 2015 14:20:31 +0000 (17:20 +0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 22 Jul 2015 21:19:37 +0000 (14:19 -0700)
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.

Cc: <stable@vger.kernel.org>
Signed-off-by: Zhuang Jin Can <jin.can.zhuang@intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/host/xhci-hub.c

index fdca8edc5836fb3155796e55a3c72f643e62855c..78241b5550df877fb09189936867f7821e09d11a 100644 (file)
@@ -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;