[1/2] thunderbolt: Fix wake configurations after device unplug

Commit Message

Mika Westerberg April 8, 2024, 12:48 p.m. UTC

From: Gil Fine <[e-mail]>

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 <[e-mail]>
Cc: [e-mail]
Signed-off-by: Mika Westerberg <[e-mail]>
---
 drivers/thunderbolt/switch.c | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

Comments

Mika Westerberg April 10, 2024, 7:53 a.m. UTC | #1

On Mon, Apr 08, 2024 at 03:48:02PM +0300, Mika Westerberg wrote:
> From: Gil Fine <[e-mail]>
> 
> 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 <[e-mail]>
> Cc: [e-mail]
> Signed-off-by: Mika Westerberg <[e-mail]>

Both applied to thunderbolt.git/fixes.

Patch

diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index 6ffc4e81ffed..4edfd6e34e31 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -3180,22 +3180,29 @@  void tb_switch_unconfigure_link(struct tb_switch *sw)
 {
 	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)