3 files changed, 98 insertions, 3 deletions

diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c
index 9aa44f9762a3..cac1ead5e302 100644
--- a/drivers/thunderbolt/nhi.c
+++ b/drivers/thunderbolt/nhi.c
@@ -27,8 +27,7 @@
  * use this ring for anything else.
  */
 #define RING_E2E_UNUSED_HOPID	2
-/* HopIDs 0-7 are reserved by the Thunderbolt protocol */
-#define RING_FIRST_USABLE_HOPID	8
+#define RING_FIRST_USABLE_HOPID	TB_PATH_MIN_HOPID
 
 /*
  * Minimal number of vectors when we use MSI-X. Two for control channel
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index b132439618da..30f3d6a9fe90 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -594,11 +594,88 @@ static int tb_init_port(struct tb_port *port)
 
 	tb_dump_port(port->sw->tb, &port->config);
 
-	/* TODO: Read dual link port, DP port and more from EEPROM. */
+	/* Control port does not need HopID allocation */
+	if (port->port) {
+		ida_init(&port->in_hopids);
+		ida_init(&port->out_hopids);
+	}
+
 	return 0;
 
 }
 
+static int tb_port_alloc_hopid(struct tb_port *port, bool in, int min_hopid,
+			       int max_hopid)
+{
+	int port_max_hopid;
+	struct ida *ida;
+
+	if (in) {
+		port_max_hopid = port->config.max_in_hop_id;
+		ida = &port->in_hopids;
+	} else {
+		port_max_hopid = port->config.max_out_hop_id;
+		ida = &port->out_hopids;
+	}
+
+	/* HopIDs 0-7 are reserved */
+	if (min_hopid < TB_PATH_MIN_HOPID)
+		min_hopid = TB_PATH_MIN_HOPID;
+
+	if (max_hopid < 0 || max_hopid > port_max_hopid)
+		max_hopid = port_max_hopid;
+
+	return ida_simple_get(ida, min_hopid, max_hopid + 1, GFP_KERNEL);
+}
+
+/**
+ * tb_port_alloc_in_hopid() - Allocate input HopID from port
+ * @port: Port to allocate HopID for
+ * @min_hopid: Minimum acceptable input HopID
+ * @max_hopid: Maximum acceptable input HopID
+ *
+ * Return: HopID between @min_hopid and @max_hopid or negative errno in
+ * case of error.
+ */
+int tb_port_alloc_in_hopid(struct tb_port *port, int min_hopid, int max_hopid)
+{
+	return tb_port_alloc_hopid(port, true, min_hopid, max_hopid);
+}
+
+/**
+ * tb_port_alloc_out_hopid() - Allocate output HopID from port
+ * @port: Port to allocate HopID for
+ * @min_hopid: Minimum acceptable output HopID
+ * @max_hopid: Maximum acceptable output HopID
+ *
+ * Return: HopID between @min_hopid and @max_hopid or negative errno in
+ * case of error.
+ */
+int tb_port_alloc_out_hopid(struct tb_port *port, int min_hopid, int max_hopid)
+{
+	return tb_port_alloc_hopid(port, false, min_hopid, max_hopid);
+}
+
+/**
+ * tb_port_release_in_hopid() - Release allocated input HopID from port
+ * @port: Port whose HopID to release
+ * @hopid: HopID to release
+ */
+void tb_port_release_in_hopid(struct tb_port *port, int hopid)
+{
+	ida_simple_remove(&port->in_hopids, hopid);
+}
+
+/**
+ * tb_port_release_out_hopid() - Release allocated output HopID from port
+ * @port: Port whose HopID to release
+ * @hopid: HopID to release
+ */
+void tb_port_release_out_hopid(struct tb_port *port, int hopid)
+{
+	ida_simple_remove(&port->out_hopids, hopid);
+}
+
 /**
  * tb_pci_port_enable() - Enable PCIe adapter port
  * @port: PCIe port to enable
@@ -1055,9 +1132,17 @@ static const struct attribute_group *switch_groups[] = {
 static void tb_switch_release(struct device *dev)
 {
 	struct tb_switch *sw = tb_to_switch(dev);
+	int i;
 
 	dma_port_free(sw->dma_port);
 
+	for (i = 1; i <= sw->config.max_port_number; i++) {
+		if (!sw->ports[i].disabled) {
+			ida_destroy(&sw->ports[i].in_hopids);
+			ida_destroy(&sw->ports[i].out_hopids);
+		}
+	}
+
 	kfree(sw->uuid);
 	kfree(sw->device_name);
 	kfree(sw->vendor_name);
diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index d1f8e9722f33..1cb5009195f9 100644
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -127,6 +127,8 @@ struct tb_switch {
  * @dual_link_port: If the switch is connected using two ports, points
  *		    to the other port.
  * @link_nr: Is this primary or secondary port on the dual_link.
+ * @in_hopids: Currently allocated input HopIDs
+ * @out_hopids: Currently allocated output HopIDs
  */
 struct tb_port {
 	struct tb_regs_port_header config;
@@ -139,6 +141,8 @@ struct tb_port {
 	bool disabled;
 	struct tb_port *dual_link_port;
 	u8 link_nr:1;
+	struct ida in_hopids;
+	struct ida out_hopids;
 };
 
 /**
@@ -194,6 +198,9 @@ struct tb_path {
 	int path_length; /* number of hops */
 };
 
+/* HopIDs 0-7 are reserved by the Thunderbolt protocol */
+#define TB_PATH_MIN_HOPID	8
+
 /**
  * struct tb_cm_ops - Connection manager specific operations vector
  * @driver_ready: Called right after control channel is started. Used by
@@ -453,6 +460,10 @@ static inline bool tb_switch_is_er(const struct tb_switch *sw)
 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);
+int tb_port_alloc_in_hopid(struct tb_port *port, int hopid, int max_hopid);
+void tb_port_release_in_hopid(struct tb_port *port, int hopid);
+int tb_port_alloc_out_hopid(struct tb_port *port, int hopid, int max_hopid);
+void tb_port_release_out_hopid(struct tb_port *port, int hopid);
 
 int tb_switch_find_vse_cap(struct tb_switch *sw, enum tb_switch_vse_cap vsec);
 int tb_port_find_cap(struct tb_port *port, enum tb_port_cap cap);