xhci: Don't prevent USB2 bus suspend in state check intended for USB3 only

commit 45f750c16cae3625014c14c77bd9005eda975d35 upstream.

The code to prevent a bus suspend if a USB3 port was still in link training
also reacted to USB2 port polling state.
This caused bus suspend to busyloop in some cases.
USB2 polling state is different from USB3, and should not prevent bus
suspend.

Limit the USB3 link training state check to USB3 root hub ports only.
The origial commit went to stable so this need to be applied there as well

Fixes: 2f31a67f01a8 ("usb: xhci: Prevent bus suspend if a port connect change or polling state is detected")
Cc: stable@vger.kernel.org
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 6b2f6c41e2a9e9a6f50c8d1ffbed88fc5c2be6cd..997ff183c9cbba856839c8dc5e169fa51cbc78b2 100644 (file)
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -1512,7 +1512,8 @@ int xhci_bus_suspend(struct usb_hcd *hcd)
                portsc_buf[port_index] = 0;
 
                /* Bail out if a USB3 port has a new device in link training */
-               if ((t1 & PORT_PLS_MASK) == XDEV_POLLING) {
+               if ((hcd->speed >= HCD_USB3) &&
+                   (t1 & PORT_PLS_MASK) == XDEV_POLLING) {
                        bus_state->bus_suspended = 0;
                        spin_unlock_irqrestore(&xhci->lock, flags);
                        xhci_dbg(xhci, "Bus suspend bailout, port in polling\n");