Merge tag 'thunderbolt-for-v5.19-rc1' of...

Merge tag 'thunderbolt-for-v5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/westeri/thunderbolt into usb-next

Mika writes:

thunderbolt: Changes for v5.19 merge window

This includes following Thunderbolt/USB4 changes for the v5.19 merge
window:

  * Improvements for Thunderbolt 1 DisplayPort tunneling
  * Link USB4 ports to their USB Type-C connectors
  * Lane bonding support for host-to-host (XDomain) connections
  * Buffer allocation improvement for devices with no DisplayPort
    adapters
  * Few cleanups and minor fixes.

All these have been in linux-next with no reported issues except that
there is a minor merge conflict with the kunit-next tree because one of
the commits touches the driver KUnit tests.

* tag 'thunderbolt-for-v5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/westeri/thunderbolt:
  thunderbolt: Add KUnit test for devices with no DisplayPort adapters
  thunderbolt: Fix buffer allocation of devices with no DisplayPort adapters
  thunderbolt: Add support for XDomain lane bonding
  thunderbolt: Ignore port locked error in tb_port_wait_for_link_width()
  thunderbolt: Split setting link width and lane bonding into own functions
  thunderbolt: Move tb_port_state() prototype to correct place
  thunderbolt: Add debug logging when lane is enabled/disabled
  thunderbolt: Link USB4 ports to their USB Type-C connectors
  misc/mei: Add NULL check to component match callback functions
  thunderbolt: Use different lane for second DisplayPort tunnel
  thunderbolt: Dump path config space entries during discovery
  thunderbolt: Use decimal number with port numbers
  thunderbolt: Fix typo in comment
  thunderbolt: Replace usage of found with dedicated list iterator variable

Documentation/ABI/testing/sysfs-bus-thunderbolt

@@ -293,6 +293,16 @@ Contact:	thunderbolt-software@lists.01.org
 Description:	This contains XDomain service specific settings as
 		bitmask. Format: %x
 
+What:		/sys/bus/thunderbolt/devices/usb4_portX/connector
+Date:		April 2022
+Contact:	Heikki Krogerus <heikki.krogerus@linux.intel.com>
+Description:
+		Symlink to the USB Type-C connector. This link is only
+		created when USB Type-C Connector Class is enabled,
+		and only if the system firmware is capable of
+		describing the connection between a port and its
+		connector.
+
 What:		/sys/bus/thunderbolt/devices/usb4_portX/link
 Date:		Sep 2021
 KernelVersion:	v5.14

drivers/misc/mei/hdcp/mei_hdcp.c

@@ -784,7 +784,7 @@ static int mei_hdcp_component_match(struct device *dev, int subcomponent,
 {
 	struct device *base = data;
 
-	if (strcmp(dev->driver->name, "i915") ||
+	if (!dev->driver || strcmp(dev->driver->name, "i915") ||
 	    subcomponent != I915_COMPONENT_HDCP)
 		return 0;
 

drivers/misc/mei/pxp/mei_pxp.c

@@ -131,7 +131,7 @@ static int mei_pxp_component_match(struct device *dev, int subcomponent,
 {
 	struct device *base = data;
 
-	if (strcmp(dev->driver->name, "i915") ||
+	if (!dev->driver || strcmp(dev->driver->name, "i915") ||
 	    subcomponent != I915_COMPONENT_PXP)
 		return 0;
 

drivers/thunderbolt/ctl.c

@@ -158,21 +158,20 @@ static bool tb_cfg_request_is_active(struct tb_cfg_request *req)
 static struct tb_cfg_request *
 tb_cfg_request_find(struct tb_ctl *ctl, struct ctl_pkg *pkg)
 {
-	struct tb_cfg_request *req;
-	bool found = false;
+	struct tb_cfg_request *req = NULL, *iter;
 
 	mutex_lock(&pkg->ctl->request_queue_lock);
-	list_for_each_entry(req, &pkg->ctl->request_queue, list) {
-		tb_cfg_request_get(req);
-		if (req->match(req, pkg)) {
-			found = true;
+	list_for_each_entry(iter, &pkg->ctl->request_queue, list) {
+		tb_cfg_request_get(iter);
+		if (iter->match(iter, pkg)) {
+			req = iter;
 			break;
 		}
-		tb_cfg_request_put(req);
+		tb_cfg_request_put(iter);
 	}
 	mutex_unlock(&pkg->ctl->request_queue_lock);
 
-	return found ? req : NULL;
+	return req;
 }
 
 /* utility functions */

drivers/thunderbolt/nhi.c

@@ -1207,7 +1207,7 @@ static int nhi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
 	nhi->pdev = pdev;
 	nhi->ops = (const struct tb_nhi_ops *)id->driver_data;
-	/* cannot fail - table is allocated bin pcim_iomap_regions */
+	/* cannot fail - table is allocated in pcim_iomap_regions */
 	nhi->iobase = pcim_iomap_table(pdev)[0];
 	nhi->hop_count = ioread32(nhi->iobase + REG_HOP_COUNT) & 0x3ff;
 	dev_dbg(&pdev->dev, "total paths: %d\n", nhi->hop_count);

drivers/thunderbolt/path.c

@@ -166,6 +166,9 @@ struct tb_path *tb_path_discover(struct tb_port *src, int src_hopid,
 		return NULL;
 	}
 
+	tb_dbg(path->tb, "discovering %s path starting from %llx:%u\n",
+	       path->name, tb_route(src->sw), src->port);
+
 	p = src;
 	h = src_hopid;
 
@@ -198,10 +201,13 @@ struct tb_path *tb_path_discover(struct tb_port *src, int src_hopid,
 		path->hops[i].out_port = out_port;
 		path->hops[i].next_hop_index = next_hop;
 
+		tb_dump_hop(&path->hops[i], &hop);
+
 		h = next_hop;
 		p = out_port->remote;
 	}
 
+	tb_dbg(path->tb, "path discovery complete\n");
 	return path;
 
 err:

drivers/thunderbolt/switch.c

@@ -693,8 +693,14 @@ static int __tb_port_enable(struct tb_port *port, bool enable)
 	else
 		phy |= LANE_ADP_CS_1_LD;
 
-	return tb_port_write(port, &phy, TB_CFG_PORT,
-			     port->cap_phy + LANE_ADP_CS_1, 1);
+
+	ret = tb_port_write(port, &phy, TB_CFG_PORT,
+			    port->cap_phy + LANE_ADP_CS_1, 1);
+	if (ret)
+		return ret;
+
+	tb_port_dbg(port, "lane %sabled\n", enable ? "en" : "dis");
+	return 0;
 }
 
 /**
@@ -993,7 +999,17 @@ static bool tb_port_is_width_supported(struct tb_port *port, int width)
 	return !!(widths & width);
 }
 
-static int tb_port_set_link_width(struct tb_port *port, unsigned int width)
+/**
+ * tb_port_set_link_width() - Set target link width of the lane adapter
+ * @port: Lane adapter
+ * @width: Target link width (%1 or %2)
+ *
+ * Sets the target link width of the lane adapter to @width. Does not
+ * enable/disable lane bonding. For that call tb_port_set_lane_bonding().
+ *
+ * Return: %0 in case of success and negative errno in case of error
+ */
+int tb_port_set_link_width(struct tb_port *port, unsigned int width)
 {
 	u32 val;
 	int ret;
@@ -1020,12 +1036,58 @@ static int tb_port_set_link_width(struct tb_port *port, unsigned int width)
 		return -EINVAL;
 	}
 
-	val |= LANE_ADP_CS_1_LB;
-
 	return tb_port_write(port, &val, TB_CFG_PORT,
 			     port->cap_phy + LANE_ADP_CS_1, 1);
 }
 
+/**
+ * tb_port_set_lane_bonding() - Enable/disable lane bonding
+ * @port: Lane adapter
+ * @bonding: enable/disable bonding
+ *
+ * Enables or disables lane bonding. This should be called after target
+ * link width has been set (tb_port_set_link_width()). Note in most
+ * cases one should use tb_port_lane_bonding_enable() instead to enable
+ * lane bonding.
+ *
+ * As a side effect sets @port->bonding accordingly (and does the same
+ * for lane 1 too).
+ *
+ * Return: %0 in case of success and negative errno in case of error
+ */
+int tb_port_set_lane_bonding(struct tb_port *port, bool bonding)
+{
+	u32 val;
+	int ret;
+
+	if (!port->cap_phy)
+		return -EINVAL;
+
+	ret = tb_port_read(port, &val, TB_CFG_PORT,
+			   port->cap_phy + LANE_ADP_CS_1, 1);
+	if (ret)
+		return ret;
+
+	if (bonding)
+		val |= LANE_ADP_CS_1_LB;
+	else
+		val &= ~LANE_ADP_CS_1_LB;
+
+	ret = tb_port_write(port, &val, TB_CFG_PORT,
+			    port->cap_phy + LANE_ADP_CS_1, 1);
+	if (ret)
+		return ret;
+
+	/*
+	 * When lane 0 bonding is set it will affect lane 1 too so
+	 * update both.
+	 */
+	port->bonded = bonding;
+	port->dual_link_port->bonded = bonding;
+
+	return 0;
+}
+
 /**
  * tb_port_lane_bonding_enable() - Enable bonding on port
  * @port: port to enable
@@ -1050,22 +1112,27 @@ int tb_port_lane_bonding_enable(struct tb_port *port)
 	if (ret == 1) {
 		ret = tb_port_set_link_width(port, 2);
 		if (ret)
-			return ret;
+			goto err_lane0;
 	}
 
 	ret = tb_port_get_link_width(port->dual_link_port);
 	if (ret == 1) {
 		ret = tb_port_set_link_width(port->dual_link_port, 2);
-		if (ret) {
-			tb_port_set_link_width(port, 1);
-			return ret;
-		}
+		if (ret)
+			goto err_lane0;
 	}
 
-	port->bonded = true;
-	port->dual_link_port->bonded = true;
+	ret = tb_port_set_lane_bonding(port, true);
+	if (ret)
+		goto err_lane1;
 
 	return 0;
+
+err_lane1:
+	tb_port_set_link_width(port->dual_link_port, 1);
+err_lane0:
+	tb_port_set_link_width(port, 1);
+	return ret;
 }
 
 /**
@@ -1074,13 +1141,10 @@ int tb_port_lane_bonding_enable(struct tb_port *port)
  *
  * Disable bonding by setting the link width of the port and the
  * other port in case of dual link port.
- *
  */
 void tb_port_lane_bonding_disable(struct tb_port *port)
 {
-	port->dual_link_port->bonded = false;
-	port->bonded = false;
-
+	tb_port_set_lane_bonding(port, false);
 	tb_port_set_link_width(port->dual_link_port, 1);
 	tb_port_set_link_width(port, 1);
 }
@@ -1104,10 +1168,17 @@ int tb_port_wait_for_link_width(struct tb_port *port, int width,
 
 	do {
 		ret = tb_port_get_link_width(port);
-		if (ret < 0)
-			return ret;
-		else if (ret == width)
+		if (ret < 0) {
+			/*
+			 * Sometimes we get port locked error when
+			 * polling the lanes so we can ignore it and
+			 * retry.
+			 */
+			if (ret != -EACCES)
+				return ret;
+		} else if (ret == width) {
 			return 0;
+		}
 
 		usleep_range(1000, 2000);
 	} while (ktime_before(ktime_get(), timeout));

drivers/thunderbolt/tb.c

@@ -169,12 +169,6 @@ static void tb_discover_tunnels(struct tb *tb)
 
 static int tb_port_configure_xdomain(struct tb_port *port)
 {
-	/*
-	 * XDomain paths currently only support single lane so we must
-	 * disable the other lane according to USB4 spec.
-	 */
-	tb_port_disable(port->dual_link_port);
-
 	if (tb_switch_is_usb4(port->sw))
 		return usb4_port_configure_xdomain(port);
 	return tb_lc_configure_xdomain(port);
@@ -867,7 +861,7 @@ static struct tb_port *tb_find_dp_out(struct tb *tb, struct tb_port *in)
 
 static void tb_tunnel_dp(struct tb *tb)
 {
-	int available_up, available_down, ret;
+	int available_up, available_down, ret, link_nr;
 	struct tb_cm *tcm = tb_priv(tb);
 	struct tb_port *port, *in, *out;
 	struct tb_tunnel *tunnel;
@@ -912,6 +906,20 @@ static void tb_tunnel_dp(struct tb *tb)
 		return;
 	}
 
+	/*
+	 * This is only applicable to links that are not bonded (so
+	 * when Thunderbolt 1 hardware is involved somewhere in the
+	 * topology). For these try to share the DP bandwidth between
+	 * the two lanes.
+	 */
+	link_nr = 1;
+	list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
+		if (tb_tunnel_is_dp(tunnel)) {
+			link_nr = 0;
+			break;
+		}
+	}
+
 	/*
 	 * DP stream needs the domain to be active so runtime resume
 	 * both ends of the tunnel.
@@ -943,7 +951,8 @@ static void tb_tunnel_dp(struct tb *tb)
 	tb_dbg(tb, "available bandwidth for new DP tunnel %u/%u Mb/s\n",
 	       available_up, available_down);
 
-	tunnel = tb_tunnel_alloc_dp(tb, in, out, available_up, available_down);
+	tunnel = tb_tunnel_alloc_dp(tb, in, out, link_nr, available_up,
+				    available_down);
 	if (!tunnel) {
 		tb_port_dbg(out, "could not allocate DP tunnel\n");
 		goto err_reclaim;

drivers/thunderbolt/tb.h

@@ -674,7 +674,7 @@ static inline int tb_port_write(struct tb_port *port, const void *buffer,
 #define __TB_PORT_PRINT(level, _port, fmt, arg...)                      \
 	do {                                                            \
 		const struct tb_port *__port = (_port);                 \
-		level(__port->sw->tb, "%llx:%x: " fmt,                  \
+		level(__port->sw->tb, "%llx:%u: " fmt,                  \
 		      tb_route(__port->sw), __port->port, ## arg);      \
 	} while (0)
 #define tb_port_WARN(port, fmt, arg...) \
@@ -991,6 +991,7 @@ int tb_switch_pcie_l1_enable(struct tb_switch *sw);
 int tb_switch_xhci_connect(struct tb_switch *sw);
 void tb_switch_xhci_disconnect(struct tb_switch *sw);
 
+int tb_port_state(struct tb_port *port);
 int tb_wait_for_port(struct tb_port *port, bool wait_if_unplugged);
 int tb_port_add_nfc_credits(struct tb_port *port, int credits);
 int tb_port_clear_counter(struct tb_port *port, int counter);
@@ -1023,7 +1024,8 @@ static inline bool tb_port_use_credit_allocation(const struct tb_port *port)
 
 int tb_port_get_link_speed(struct tb_port *port);
 int tb_port_get_link_width(struct tb_port *port);
-int tb_port_state(struct tb_port *port);
+int tb_port_set_link_width(struct tb_port *port, unsigned int width);
+int tb_port_set_lane_bonding(struct tb_port *port, bool bonding);
 int tb_port_lane_bonding_enable(struct tb_port *port);
 void tb_port_lane_bonding_disable(struct tb_port *port);
 int tb_port_wait_for_link_width(struct tb_port *port, int width,

drivers/thunderbolt/tb_msgs.h

@@ -527,6 +527,10 @@ enum tb_xdp_type {
 	PROPERTIES_CHANGED_RESPONSE,
 	ERROR_RESPONSE,
 	UUID_REQUEST = 12,
+	LINK_STATE_STATUS_REQUEST = 15,
+	LINK_STATE_STATUS_RESPONSE,
+	LINK_STATE_CHANGE_REQUEST,
+	LINK_STATE_CHANGE_RESPONSE,
 };
 
 struct tb_xdp_header {
@@ -540,6 +544,41 @@ struct tb_xdp_error_response {
 	u32 error;
 };
 
+struct tb_xdp_link_state_status {
+	struct tb_xdp_header hdr;
+};
+
+struct tb_xdp_link_state_status_response {
+	union {
+		struct tb_xdp_error_response err;
+		struct {
+			struct tb_xdp_header hdr;
+			u32 status;
+			u8 slw;
+			u8 tlw;
+			u8 sls;
+			u8 tls;
+		};
+	};
+};
+
+struct tb_xdp_link_state_change {
+	struct tb_xdp_header hdr;
+	u8 tlw;
+	u8 tls;
+	u16 reserved;
+};
+
+struct tb_xdp_link_state_change_response {
+	union {
+		struct tb_xdp_error_response err;
+		struct {
+			struct tb_xdp_header hdr;
+			u32 status;
+		};
+	};
+};
+
 struct tb_xdp_uuid {
 	struct tb_xdp_header hdr;
 };

drivers/thunderbolt/tb_regs.h

@@ -311,11 +311,16 @@ struct tb_regs_port_header {
 
 /* Lane adapter registers */
 #define LANE_ADP_CS_0				0x00
+#define LANE_ADP_CS_0_SUPPORTED_SPEED_MASK	GENMASK(19, 16)
+#define LANE_ADP_CS_0_SUPPORTED_SPEED_SHIFT	16
 #define LANE_ADP_CS_0_SUPPORTED_WIDTH_MASK	GENMASK(25, 20)
 #define LANE_ADP_CS_0_SUPPORTED_WIDTH_SHIFT	20
+#define LANE_ADP_CS_0_SUPPORTED_WIDTH_DUAL	0x2
 #define LANE_ADP_CS_0_CL0S_SUPPORT		BIT(26)
 #define LANE_ADP_CS_0_CL1_SUPPORT		BIT(27)
 #define LANE_ADP_CS_1				0x01
+#define LANE_ADP_CS_1_TARGET_SPEED_MASK		GENMASK(3, 0)
+#define LANE_ADP_CS_1_TARGET_SPEED_GEN3		0xc
 #define LANE_ADP_CS_1_TARGET_WIDTH_MASK		GENMASK(9, 4)
 #define LANE_ADP_CS_1_TARGET_WIDTH_SHIFT	4
 #define LANE_ADP_CS_1_TARGET_WIDTH_SINGLE	0x1

drivers/thunderbolt/test.c

@@ -341,6 +341,47 @@ static struct tb_switch *alloc_dev_with_dpin(struct kunit *test,
 	return sw;
 }
 
+static struct tb_switch *alloc_dev_without_dp(struct kunit *test,
+					      struct tb_switch *parent,
+					      u64 route, bool bonded)
+{
+	struct tb_switch *sw;
+	int i;
+
+	sw = alloc_dev_default(test, parent, route, bonded);
+	if (!sw)
+		return NULL;
+	/*
+	 * Device with:
+	 * 2x USB4 Adapters (adapters 1,2 and 3,4),
+	 * 1x PCIe Upstream (adapter 9),
+	 * 1x PCIe Downstream (adapter 10),
+	 * 1x USB3 Upstream (adapter 16),
+	 * 1x USB3 Downstream (adapter 17)
+	 */
+	for (i = 5; i <= 8; i++)
+		sw->ports[i].disabled = true;
+
+	for (i = 11; i <= 14; i++)
+		sw->ports[i].disabled = true;
+
+	sw->ports[13].cap_adap = 0;
+	sw->ports[14].cap_adap = 0;
+
+	for (i = 18; i <= 19; i++)
+		sw->ports[i].disabled = true;
+
+	sw->generation = 4;
+	sw->credit_allocation = true;
+	sw->max_usb3_credits = 109;
+	sw->min_dp_aux_credits = 0;
+	sw->min_dp_main_credits = 0;
+	sw->max_pcie_credits = 30;
+	sw->max_dma_credits = 1;
+
+	return sw;
+}
+
 static struct tb_switch *alloc_dev_usb4(struct kunit *test,
 					struct tb_switch *parent,
 					u64 route, bool bonded)
@@ -1348,7 +1389,7 @@ static void tb_test_tunnel_dp(struct kunit *test)
 	in = &host->ports[5];
 	out = &dev->ports[13];
 
-	tunnel = tb_tunnel_alloc_dp(NULL, in, out, 0, 0);
+	tunnel = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0);
 	KUNIT_ASSERT_TRUE(test, tunnel != NULL);
 	KUNIT_EXPECT_EQ(test, tunnel->type, TB_TUNNEL_DP);
 	KUNIT_EXPECT_PTR_EQ(test, tunnel->src_port, in);
@@ -1394,7 +1435,7 @@ static void tb_test_tunnel_dp_chain(struct kunit *test)
 	in = &host->ports[5];
 	out = &dev4->ports[14];
 
-	tunnel = tb_tunnel_alloc_dp(NULL, in, out, 0, 0);
+	tunnel = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0);
 	KUNIT_ASSERT_TRUE(test, tunnel != NULL);
 	KUNIT_EXPECT_EQ(test, tunnel->type, TB_TUNNEL_DP);
 	KUNIT_EXPECT_PTR_EQ(test, tunnel->src_port, in);
@@ -1444,7 +1485,7 @@ static void tb_test_tunnel_dp_tree(struct kunit *test)
 	in = &dev2->ports[13];
 	out = &dev5->ports[13];
 
-	tunnel = tb_tunnel_alloc_dp(NULL, in, out, 0, 0);
+	tunnel = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0);
 	KUNIT_ASSERT_TRUE(test, tunnel != NULL);
 	KUNIT_EXPECT_EQ(test, tunnel->type, TB_TUNNEL_DP);
 	KUNIT_EXPECT_PTR_EQ(test, tunnel->src_port, in);
@@ -1509,7 +1550,7 @@ static void tb_test_tunnel_dp_max_length(struct kunit *test)
 	in = &dev6->ports[13];
 	out = &dev12->ports[13];
 
-	tunnel = tb_tunnel_alloc_dp(NULL, in, out, 0, 0);
+	tunnel = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0);
 	KUNIT_ASSERT_TRUE(test, tunnel != NULL);
 	KUNIT_EXPECT_EQ(test, tunnel->type, TB_TUNNEL_DP);
 	KUNIT_EXPECT_PTR_EQ(test, tunnel->src_port, in);
@@ -1627,7 +1668,7 @@ static void tb_test_tunnel_port_on_path(struct kunit *test)
 	in = &dev2->ports[13];
 	out = &dev5->ports[13];
 
-	dp_tunnel = tb_tunnel_alloc_dp(NULL, in, out, 0, 0);
+	dp_tunnel = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0);
 	KUNIT_ASSERT_TRUE(test, dp_tunnel != NULL);
 
 	KUNIT_EXPECT_TRUE(test, tb_tunnel_port_on_path(dp_tunnel, in));
@@ -1996,6 +2037,56 @@ static void tb_test_credit_alloc_pcie(struct kunit *test)
 	tb_tunnel_free(tunnel);
 }
 
+static void tb_test_credit_alloc_without_dp(struct kunit *test)
+{
+	struct tb_switch *host, *dev;
+	struct tb_port *up, *down;
+	struct tb_tunnel *tunnel;
+	struct tb_path *path;
+
+	host = alloc_host_usb4(test);
+	dev = alloc_dev_without_dp(test, host, 0x1, true);
+
+	/*
+	 * The device has no DP therefore baMinDPmain = baMinDPaux = 0
+	 *
+	 * Create PCIe path with buffers less than baMaxPCIe.
+	 *
+	 * For a device with buffers configurations:
+	 * baMaxUSB3 = 109
+	 * baMinDPaux = 0
+	 * baMinDPmain = 0
+	 * baMaxPCIe = 30
+	 * baMaxHI = 1
+	 * Remaining Buffers = Total - (CP + DP) = 120 - (2 + 0) = 118
+	 * PCIe Credits = Max(6, Min(baMaxPCIe, Remaining Buffers - baMaxUSB3)
+	 *		= Max(6, Min(30, 9) = 9
+	 */
+	down = &host->ports[8];
+	up = &dev->ports[9];
+	tunnel = tb_tunnel_alloc_pci(NULL, up, down);
+	KUNIT_ASSERT_TRUE(test, tunnel != NULL);
+	KUNIT_ASSERT_EQ(test, tunnel->npaths, (size_t)2);
+
+	/* PCIe downstream path */
+	path = tunnel->paths[0];
+	KUNIT_ASSERT_EQ(test, path->path_length, 2);
+	KUNIT_EXPECT_EQ(test, path->hops[0].nfc_credits, 0U);
+	KUNIT_EXPECT_EQ(test, path->hops[0].initial_credits, 7U);
+	KUNIT_EXPECT_EQ(test, path->hops[1].nfc_credits, 0U);
+	KUNIT_EXPECT_EQ(test, path->hops[1].initial_credits, 9U);
+
+	/* PCIe upstream path */
+	path = tunnel->paths[1];
+	KUNIT_ASSERT_EQ(test, path->path_length, 2);
+	KUNIT_EXPECT_EQ(test, path->hops[0].nfc_credits, 0U);
+	KUNIT_EXPECT_EQ(test, path->hops[0].initial_credits, 7U);
+	KUNIT_EXPECT_EQ(test, path->hops[1].nfc_credits, 0U);
+	KUNIT_EXPECT_EQ(test, path->hops[1].initial_credits, 64U);
+
+	tb_tunnel_free(tunnel);
+}
+
 static void tb_test_credit_alloc_dp(struct kunit *test)
 {
 	struct tb_switch *host, *dev;
@@ -2009,7 +2100,7 @@ static void tb_test_credit_alloc_dp(struct kunit *test)
 	in = &host->ports[5];
 	out = &dev->ports[14];
 
-	tunnel = tb_tunnel_alloc_dp(NULL, in, out, 0, 0);
+	tunnel = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0);
 	KUNIT_ASSERT_TRUE(test, tunnel != NULL);
 	KUNIT_ASSERT_EQ(test, tunnel->npaths, (size_t)3);
 
@@ -2245,7 +2336,7 @@ static struct tb_tunnel *TB_TEST_DP_TUNNEL1(struct kunit *test,
 
 	in = &host->ports[5];
 	out = &dev->ports[13];
-	dp_tunnel1 = tb_tunnel_alloc_dp(NULL, in, out, 0, 0);
+	dp_tunnel1 = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0);
 	KUNIT_ASSERT_TRUE(test, dp_tunnel1 != NULL);
 	KUNIT_ASSERT_EQ(test, dp_tunnel1->npaths, (size_t)3);
 
@@ -2282,7 +2373,7 @@ static struct tb_tunnel *TB_TEST_DP_TUNNEL2(struct kunit *test,
 
 	in = &host->ports[6];
 	out = &dev->ports[14];
-	dp_tunnel2 = tb_tunnel_alloc_dp(NULL, in, out, 0, 0);
+	dp_tunnel2 = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0);
 	KUNIT_ASSERT_TRUE(test, dp_tunnel2 != NULL);
 	KUNIT_ASSERT_EQ(test, dp_tunnel2->npaths, (size_t)3);
 
@@ -2709,6 +2800,7 @@ static struct kunit_case tb_test_cases[] = {
 	KUNIT_CASE(tb_test_credit_alloc_legacy_not_bonded),
 	KUNIT_CASE(tb_test_credit_alloc_legacy_bonded),
 	KUNIT_CASE(tb_test_credit_alloc_pcie),
+	KUNIT_CASE(tb_test_credit_alloc_without_dp),
 	KUNIT_CASE(tb_test_credit_alloc_dp),
 	KUNIT_CASE(tb_test_credit_alloc_usb3),
 	KUNIT_CASE(tb_test_credit_alloc_dma),

drivers/thunderbolt/tunnel.c

@@ -102,8 +102,11 @@ static unsigned int tb_available_credits(const struct tb_port *port,
 		 * Maximum number of DP streams possible through the
 		 * lane adapter.
 		 */
-		ndp = (credits - (usb3 + pcie + spare)) /
-		      (sw->min_dp_aux_credits + sw->min_dp_main_credits);
+		if (sw->min_dp_aux_credits + sw->min_dp_main_credits)
+			ndp = (credits - (usb3 + pcie + spare)) /
+			      (sw->min_dp_aux_credits + sw->min_dp_main_credits);
+		else
+			ndp = 0;
 	} else {
 		ndp = 0;
 	}
@@ -858,6 +861,7 @@ struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in,
  * @tb: Pointer to the domain structure
  * @in: DP in adapter port
  * @out: DP out adapter port
+ * @link_nr: Preferred lane adapter when the link is not bonded
  * @max_up: Maximum available upstream bandwidth for the DP tunnel (%0
  *	    if not limited)
  * @max_down: Maximum available downstream bandwidth for the DP tunnel
@@ -869,8 +873,8 @@ struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in,
  * Return: Returns a tb_tunnel on success or NULL on failure.
  */
 struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in,
-				     struct tb_port *out, int max_up,
-				     int max_down)
+				     struct tb_port *out, int link_nr,
+				     int max_up, int max_down)
 {
 	struct tb_tunnel *tunnel;
 	struct tb_path **paths;
@@ -894,21 +898,21 @@ struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in,
 	paths = tunnel->paths;
 
 	path = tb_path_alloc(tb, in, TB_DP_VIDEO_HOPID, out, TB_DP_VIDEO_HOPID,
-			     1, "Video");
+			     link_nr, "Video");
 	if (!path)
 		goto err_free;
 	tb_dp_init_video_path(path);
 	paths[TB_DP_VIDEO_PATH_OUT] = path;
 
 	path = tb_path_alloc(tb, in, TB_DP_AUX_TX_HOPID, out,
-			     TB_DP_AUX_TX_HOPID, 1, "AUX TX");
+			     TB_DP_AUX_TX_HOPID, link_nr, "AUX TX");
 	if (!path)
 		goto err_free;
 	tb_dp_init_aux_path(path);
 	paths[TB_DP_AUX_PATH_OUT] = path;
 
 	path = tb_path_alloc(tb, out, TB_DP_AUX_RX_HOPID, in,
-			     TB_DP_AUX_RX_HOPID, 1, "AUX RX");
+			     TB_DP_AUX_RX_HOPID, link_nr, "AUX RX");
 	if (!path)
 		goto err_free;
 	tb_dp_init_aux_path(path);

drivers/thunderbolt/tunnel.h

@@ -71,8 +71,8 @@ struct tb_tunnel *tb_tunnel_alloc_pci(struct tb *tb, struct tb_port *up,
 struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in,
 					bool alloc_hopid);
 struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in,
-				     struct tb_port *out, int max_up,
-				     int max_down);
+				     struct tb_port *out, int link_nr,
+				     int max_up, int max_down);
 struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi,
 				      struct tb_port *dst, int transmit_path,
 				      int transmit_ring, int receive_path,

drivers/thunderbolt/usb4_port.c

@@ -7,9 +7,37 @@
  */
 
 #include <linux/pm_runtime.h>
+#include <linux/component.h>
+#include <linux/property.h>
 
 #include "tb.h"
 
+static int connector_bind(struct device *dev, struct device *connector, void *data)
+{
+	int ret;
+
+	ret = sysfs_create_link(&dev->kobj, &connector->kobj, "connector");
+	if (ret)
+		return ret;
+
+	ret = sysfs_create_link(&connector->kobj, &dev->kobj, dev_name(dev));
+	if (ret)
+		sysfs_remove_link(&dev->kobj, "connector");
+
+	return ret;
+}
+
+static void connector_unbind(struct device *dev, struct device *connector, void *data)
+{
+	sysfs_remove_link(&connector->kobj, dev_name(dev));
+	sysfs_remove_link(&dev->kobj, "connector");
+}
+
+static const struct component_ops connector_ops = {
+	.bind = connector_bind,
+	.unbind = connector_unbind,
+};
+
 static ssize_t link_show(struct device *dev, struct device_attribute *attr,
 			 char *buf)
 {
@@ -246,6 +274,14 @@ struct usb4_port *usb4_port_device_add(struct tb_port *port)
 		return ERR_PTR(ret);
 	}
 
+	if (dev_fwnode(&usb4->dev)) {
+		ret = component_add(&usb4->dev, &connector_ops);
+		if (ret) {
+			dev_err(&usb4->dev, "failed to add component\n");
+			device_unregister(&usb4->dev);
+		}
+	}
+
 	pm_runtime_no_callbacks(&usb4->dev);
 	pm_runtime_set_active(&usb4->dev);
 	pm_runtime_enable(&usb4->dev);
@@ -265,6 +301,8 @@ struct usb4_port *usb4_port_device_add(struct tb_port *port)
  */
 void usb4_port_device_remove(struct usb4_port *usb4)
 {
+	if (dev_fwnode(&usb4->dev))
+		component_del(&usb4->dev, &connector_ops);
 	device_unregister(&usb4->dev);
 }
 

include/linux/thunderbolt.h

@@ -198,15 +198,15 @@ void tb_unregister_property_dir(const char *key, struct tb_property_dir *dir);
  * @local_property_block_len: Length of the @local_property_block in dwords
  * @remote_properties: Properties exported by the remote domain
  * @remote_property_block_gen: Generation of @remote_properties
- * @get_uuid_work: Work used to retrieve @remote_uuid
- * @uuid_retries: Number of times left @remote_uuid is requested before
- *		  giving up
- * @get_properties_work: Work used to get remote domain properties
- * @properties_retries: Number of times left to read properties
+ * @state: Next XDomain discovery state to run
+ * @state_work: Work used to run the next state
+ * @state_retries: Number of retries remain for the state
  * @properties_changed_work: Work used to notify the remote domain that
  *			     our properties have changed
  * @properties_changed_retries: Number of times left to send properties
  *				changed notification
+ * @bonding_possible: True if lane bonding is possible on local side
+ * @target_link_width: Target link width from the remote host
  * @link: Root switch link the remote domain is connected (ICM only)
  * @depth: Depth in the chain the remote domain is connected (ICM only)
  *
@@ -244,12 +244,13 @@ struct tb_xdomain {
 	u32 local_property_block_len;
 	struct tb_property_dir *remote_properties;
 	u32 remote_property_block_gen;
-	struct delayed_work get_uuid_work;
-	int uuid_retries;
-	struct delayed_work get_properties_work;
-	int properties_retries;
+	int state;
+	struct delayed_work state_work;
+	int state_retries;
 	struct delayed_work properties_changed_work;
 	int properties_changed_retries;
+	bool bonding_possible;
+	u8 target_link_width;
 	u8 link;
 	u8 depth;
 };