thunderbolt: Configure link after lane bonding is enabled

During testing it was noticed that the link is not properly restored
after the domain exits sleep if the link configured bits are set before
lane bonding is enabled. The USB4 spec does not say in which order these
need to be set but setting link configured afterwards makes the link
restoration work so we do that instead.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

5 files changed, 49 insertions, 25 deletions

diff --git a/drivers/thunderbolt/lc.c b/drivers/thunderbolt/lc.c
index 19be627d090f..b2f62ba0421d 100644
--- a/drivers/thunderbolt/lc.c
+++ b/drivers/thunderbolt/lc.c
@@ -94,9 +94,6 @@ int tb_lc_configure_link(struct tb_switch *sw)
 	struct tb_port *up, *down;
 	int ret;
 
-	if (!tb_route(sw) || tb_switch_is_icm(sw))
-		return 0;
-
 	up = tb_upstream_port(sw);
 	down = tb_port_at(tb_route(sw), tb_to_switch(sw->dev.parent));
 
@@ -124,9 +121,6 @@ void tb_lc_unconfigure_link(struct tb_switch *sw)
 {
 	struct tb_port *up, *down;
 
-	if (sw->is_unplugged || !tb_route(sw) || tb_switch_is_icm(sw))
-		return;
-
 	up = tb_upstream_port(sw);
 	down = tb_port_at(tb_route(sw), tb_to_switch(sw->dev.parent));
 
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index 02f981ee88e9..5d99d69107eb 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -2011,10 +2011,6 @@ int tb_switch_configure(struct tb_switch *sw)
 			return ret;
 
 		ret = usb4_switch_setup(sw);
-		if (ret)
-			return ret;
-
-		ret = usb4_switch_configure_link(sw);
 	} else {
 		if (sw->config.vendor_id != PCI_VENDOR_ID_INTEL)
 			tb_sw_warn(sw, "unknown switch vendor id %#x\n",
@@ -2028,10 +2024,6 @@ int tb_switch_configure(struct tb_switch *sw)
 		/* Enumerate the switch */
 		ret = tb_sw_write(sw, (u32 *)&sw->config + 1, TB_CFG_SWITCH,
 				  ROUTER_CS_1, 3);
-		if (ret)
-			return ret;
-
-		ret = tb_lc_configure_link(sw);
 	}
 	if (ret)
 		return ret;
@@ -2315,6 +2307,48 @@ void tb_switch_lane_bonding_disable(struct tb_switch *sw)
 }
 
 /**
+ * tb_switch_configure_link() - Set link configured
+ * @sw: Switch whose link is configured
+ *
+ * Sets the link upstream from @sw configured (from both ends) so that
+ * it will not be disconnected when the domain exits sleep. Can be
+ * called for any switch.
+ *
+ * It is recommended that this is called after lane bonding is enabled.
+ *
+ * Returns %0 on success and negative errno in case of error.
+ */
+int tb_switch_configure_link(struct tb_switch *sw)
+{
+	if (!tb_route(sw) || tb_switch_is_icm(sw))
+		return 0;
+
+	if (tb_switch_is_usb4(sw))
+		return usb4_switch_configure_link(sw);
+	return tb_lc_configure_link(sw);
+}
+
+/**
+ * tb_switch_unconfigure_link() - Unconfigure link
+ * @sw: Switch whose link is unconfigured
+ *
+ * Sets the link unconfigured so the @sw will be disconnected if the
+ * domain exists sleep.
+ */
+void tb_switch_unconfigure_link(struct tb_switch *sw)
+{
+	if (sw->is_unplugged)
+		return;
+	if (!tb_route(sw) || tb_switch_is_icm(sw))
+		return;
+
+	if (tb_switch_is_usb4(sw))
+		usb4_switch_unconfigure_link(sw);
+	else
+		tb_lc_unconfigure_link(sw);
+}
+
+/**
  * tb_switch_add() - Add a switch to the domain
  * @sw: Switch to add
  *
@@ -2448,11 +2482,6 @@ void tb_switch_remove(struct tb_switch *sw)
 	if (!sw->is_unplugged)
 		tb_plug_events_active(sw, false);
 
-	if (tb_switch_is_usb4(sw))
-		usb4_switch_unconfigure_link(sw);
-	else
-		tb_lc_unconfigure_link(sw);
-
 	tb_switch_nvm_remove(sw);
 
 	if (tb_route(sw))
diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c
index c35d5fec48f4..54a4daf0b1b4 100644
--- a/drivers/thunderbolt/tb.c
+++ b/drivers/thunderbolt/tb.c
@@ -593,6 +593,8 @@ static void tb_scan_port(struct tb_port *port)
 
 	/* Enable lane bonding if supported */
 	tb_switch_lane_bonding_enable(sw);
+	/* Set the link configured */
+	tb_switch_configure_link(sw);
 
 	if (tb_enable_tmu(sw))
 		tb_sw_warn(sw, "failed to enable TMU\n");
@@ -681,6 +683,7 @@ static void tb_free_unplugged_children(struct tb_switch *sw)
 		if (port->remote->sw->is_unplugged) {
 			tb_retimer_remove_all(port);
 			tb_remove_dp_resources(port->remote->sw);
+			tb_switch_unconfigure_link(port->remote->sw);
 			tb_switch_lane_bonding_disable(port->remote->sw);
 			tb_switch_remove(port->remote->sw);
 			port->remote = NULL;
@@ -1076,6 +1079,7 @@ static void tb_handle_hotplug(struct work_struct *work)
 			tb_free_invalid_tunnels(tb);
 			tb_remove_dp_resources(port->remote->sw);
 			tb_switch_tmu_disable(port->remote->sw);
+			tb_switch_unconfigure_link(port->remote->sw);
 			tb_switch_lane_bonding_disable(port->remote->sw);
 			tb_switch_remove(port->remote->sw);
 			port->remote = NULL;
@@ -1269,6 +1273,7 @@ static void tb_restore_children(struct tb_switch *sw)
 			continue;
 
 		tb_switch_lane_bonding_enable(port->remote->sw);
+		tb_switch_configure_link(port->remote->sw);
 
 		tb_restore_children(port->remote->sw);
 	}
diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index b16d290690f3..4f7f3b44af00 100644
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -767,6 +767,8 @@ static inline bool tb_switch_is_icm(const struct tb_switch *sw)
 
 int tb_switch_lane_bonding_enable(struct tb_switch *sw);
 void tb_switch_lane_bonding_disable(struct tb_switch *sw);
+int tb_switch_configure_link(struct tb_switch *sw);
+void tb_switch_unconfigure_link(struct tb_switch *sw);
 
 bool tb_switch_query_dp_resource(struct tb_switch *sw, struct tb_port *in);
 int tb_switch_alloc_dp_resource(struct tb_switch *sw, struct tb_port *in);
diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c
index 2b8355e6b65f..dd601a6db23c 100644
--- a/drivers/thunderbolt/usb4.c
+++ b/drivers/thunderbolt/usb4.c
@@ -368,9 +368,6 @@ int usb4_switch_configure_link(struct tb_switch *sw)
 {
 	struct tb_port *up;
 
-	if (!tb_route(sw))
-		return 0;
-
 	up = tb_upstream_port(sw);
 	return usb4_set_port_configured(up, true);
 }
@@ -385,9 +382,6 @@ void usb4_switch_unconfigure_link(struct tb_switch *sw)
 {
 	struct tb_port *up;
 
-	if (sw->is_unplugged || !tb_route(sw))
-		return;
-
 	up = tb_upstream_port(sw);
 	usb4_set_port_configured(up, false);
 }