queue-4.4/xhci-don-t-print-a-warning-when-setting-link-state-for-disabled-ports.patch

   1 From 1208d8a84fdcae6b395c57911cdf907450d30e70 Mon Sep 17 00:00:00 2001
   2 From: Mathias Nyman <mathias.nyman@linux.intel.com>
   3 Date: Mon, 12 Feb 2018 14:24:47 +0200
   4 Subject: xhci: Don't print a warning when setting link state for disabled ports
   5
   6 From: Mathias Nyman <mathias.nyman@linux.intel.com>
   7
   8 commit 1208d8a84fdcae6b395c57911cdf907450d30e70 upstream.
   9
  10 When disabling a USB3 port the hub driver will set the port link state to
  11 U3 to prevent "ejected" or "safely removed" devices that are still
  12 physically connected from immediately re-enumerating.
  13
  14 If the device was really unplugged, then error messages were printed
  15 as the hub tries to set the U3 link state for a port that is no longer
  16 enabled.
  17
  18 xhci-hcd ee000000.usb: Cannot set link state.
  19 usb usb8-port1: cannot disable (err = -32)
  20
  21 Don't print error message in xhci-hub if hub tries to set port link state
  22 for a disabled port. Return -ENODEV instead which also silences hub driver.
  23
  24 Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
  25 Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
  26 Signed-off-by: Ross Zwisler <zwisler@google.com>
  27 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  28
  29 ---
  30  drivers/usb/host/xhci-hub.c |   18 +++++++++---------
  31  1 file changed, 9 insertions(+), 9 deletions(-)
  32
  33 --- a/drivers/usb/host/xhci-hub.c
  34 +++ b/drivers/usb/host/xhci-hub.c
  35 @@ -1048,17 +1048,17 @@ int xhci_hub_control(struct usb_hcd *hcd
  36                                 temp = readl(port_array[wIndex]);
  37                                 break;
  38                         }
  39 -
  40 -                       /* Software should not attempt to set
  41 -                        * port link state above '3' (U3) and the port
  42 -                        * must be enabled.
  43 -                        */
  44 -                       if ((temp & PORT_PE) == 0 ||
  45 -                               (link_state > USB_SS_PORT_LS_U3)) {
  46 -                               xhci_warn(xhci, "Cannot set link state.\n");
  47 +                       /* Port must be enabled */
  48 +                       if (!(temp & PORT_PE)) {
  49 +                               retval = -ENODEV;
  50 +                               break;
  51 +                       }
  52 +                       /* Can't set port link state above '3' (U3) */
  53 +                       if (link_state > USB_SS_PORT_LS_U3) {
  54 +                               xhci_warn(xhci, "Cannot set port %d link state %d\n",
  55 +                                        wIndex, link_state);
  56                                 goto error;
  57                         }
  58 -
  59                         if (link_state == USB_SS_PORT_LS_U3) {
  60                                 slot_id = xhci_find_slot_id_by_port(hcd, xhci,
  61                                                 wIndex + 1);