usb: port: Don't try to peer unused USB ports based on location

commit 69c63350e573367f9c8594162288cffa8a26d0d1 upstream.

Unused USB ports may have bogus location data in ACPI PLD tables.
This causes port peering failures as these unused USB2 and USB3 ports
location may match.

Due to these failures the driver prints a
"usb: port power management may be unreliable" warning, and
unnecessarily blocks port power off during runtime suspend.

This was debugged on a couple DELL systems where the unused ports
all returned zeroes in their location data.
Similar bugreports exist for other systems.

Don't try to peer or match ports that have connect type set to
USB_PORT_NOT_USED.

Fixes: 3bfd659baec8 ("usb: find internal hub tier mismatch via acpi")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218465
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218486
Tested-by: Paul Menzel <pmenzel@molgen.mpg.de>
Link: https://lore.kernel.org/linux-usb/5406d361-f5b7-4309-b0e6-8c94408f7d75@molgen.mpg.de
Cc: stable@vger.kernel.org # v3.16+
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218490
Link: https://lore.kernel.org/r/20240222233343.71856-1-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
index dfcca9c876c7367dce5a1c06f00bc498e0b0f026..1f2e2a39b70fdc87852f2a1e50b052943901ed78 100644 (file)
--- a/drivers/usb/core/port.c
+++ b/drivers/usb/core/port.c
@@ -450,7 +450,7 @@ static int match_location(struct usb_device *peer_hdev, void *p)
        struct usb_hub *peer_hub = usb_hub_to_struct_hub(peer_hdev);
        struct usb_device *hdev = to_usb_device(port_dev->dev.parent->parent);
 
-       if (!peer_hub)
+       if (!peer_hub || port_dev->connect_type == USB_PORT_NOT_USED)
                return 0;
 
        hcd = bus_to_hcd(hdev->bus);
@@ -461,7 +461,8 @@ static int match_location(struct usb_device *peer_hdev, void *p)
 
        for (port1 = 1; port1 <= peer_hdev->maxchild; port1++) {
                peer = peer_hub->ports[port1 - 1];
-               if (peer && peer->location == port_dev->location) {
+               if (peer && peer->connect_type != USB_PORT_NOT_USED &&
+                   peer->location == port_dev->location) {
                        link_peers_report(port_dev, peer);
                        return 1; /* done */
                }