[PATCH 5.15 43/71] thunderbolt: Fix wake configurations after device unplug

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

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

------------------

From: Gil Fine <gil.fine@linux.intel.com>

commit c38fa07dc69f0b9e6f43ecab96dc7861a70c827c upstream.

Currently we don't configure correctly the wake events after unplug of device
router. What can happen is that the downstream ports of host router will be
configured to wake on: USB4-wake and wake-on-disconnect, but not on
wake-on-connect. This may cause the later plugged device not to wake the
domain and fail in enumeration. Fix this by clearing downstream port's "USB4
Port is Configured" bit, after unplug of a device router.

Signed-off-by: Gil Fine <gil.fine@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/thunderbolt/switch.c |   21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -2669,22 +2669,29 @@ void tb_switch_unconfigure_link(struct t
 {
 	struct tb_port *up, *down;
 
-	if (sw->is_unplugged)
-		return;
 	if (!tb_route(sw) || tb_switch_is_icm(sw))
 		return;
 
+	/*
+	 * Unconfigure downstream port so that wake-on-connect can be
+	 * configured after router unplug. No need to unconfigure upstream port
+	 * since its router is unplugged.
+	 */
 	up = tb_upstream_port(sw);
-	if (tb_switch_is_usb4(up->sw))
-		usb4_port_unconfigure(up);
-	else
-		tb_lc_unconfigure_port(up);
-
 	down = up->remote;
 	if (tb_switch_is_usb4(down->sw))
 		usb4_port_unconfigure(down);
 	else
 		tb_lc_unconfigure_port(down);
+
+	if (sw->is_unplugged)
+		return;
+
+	up = tb_upstream_port(sw);
+	if (tb_switch_is_usb4(up->sw))
+		usb4_port_unconfigure(up);
+	else
+		tb_lc_unconfigure_port(up);
 }
 
 static void tb_switch_credits_init(struct tb_switch *sw)