diff --git a/drivers/thunderbolt/ctl.h b/drivers/thunderbolt/ctl.h
new file mode 100644
index 0000000..ba87d6e
--- /dev/null
+++ b/drivers/thunderbolt/ctl.h
@@ -0,0 +1,75 @@
+/*
+ * Thunderbolt Cactus Ridge driver - control channel and configuration commands
+ *
+ * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
+ */
+
+#ifndef _TB_CFG
+#define _TB_CFG
+
+#include "nhi.h"
+
+/* control channel */
+struct tb_ctl;
+
+typedef void (*hotplug_cb)(void *data, u64 route, u8 port, bool unplug);
+
+struct tb_ctl *tb_ctl_alloc(struct tb_nhi *nhi, hotplug_cb cb, void *cb_data);
+void tb_ctl_start(struct tb_ctl *ctl);
+void tb_ctl_stop(struct tb_ctl *ctl);
+void tb_ctl_free(struct tb_ctl *ctl);
+
+/* configuration commands */
+
+#define TB_CFG_DEFAULT_TIMEOUT 5000 /* msec */
+
+enum tb_cfg_space {
+	TB_CFG_HOPS = 0,
+	TB_CFG_PORT = 1,
+	TB_CFG_SWITCH = 2,
+	TB_CFG_COUNTERS = 3,
+};
+
+enum tb_cfg_error {
+	TB_CFG_ERROR_PORT_NOT_CONNECTED = 0,
+	TB_CFG_ERROR_INVALID_CONFIG_SPACE = 2,
+	TB_CFG_ERROR_NO_SUCH_PORT = 4,
+	TB_CFG_ERROR_ACK_PLUG_EVENT = 7, /* send as reply to TB_CFG_PKG_EVENT */
+	TB_CFG_ERROR_LOOP = 8,
+};
+
+struct tb_cfg_result {
+	u64 response_route;
+	u32 response_port; /*
+			    * If err = 1 then this is the port that send the
+			    * error.
+			    * If err = 0 and if this was a cfg_read/write then
+			    * this is the the upstream port of the responding
+			    * switch.
+			    * Otherwise the field is set to zero.
+			    */
+	int err; /* negative errors, 0 for success, 1 for tb errors */
+	enum tb_cfg_error tb_error; /* valid if err == 1 */
+};
+
+
+int tb_cfg_error(struct tb_ctl *ctl, u64 route, u32 port,
+		 enum tb_cfg_error error);
+struct tb_cfg_result tb_cfg_reset(struct tb_ctl *ctl, u64 route,
+				  int timeout_msec);
+struct tb_cfg_result tb_cfg_read_raw(struct tb_ctl *ctl, void *buffer,
+				     u64 route, u32 port,
+				     enum tb_cfg_space space, u32 offset,
+				     u32 length, int timeout_msec);
+struct tb_cfg_result tb_cfg_write_raw(struct tb_ctl *ctl, void *buffer,
+				      u64 route, u32 port,
+				      enum tb_cfg_space space, u32 offset,
+				      u32 length, int timeout_msec);
+int tb_cfg_read(struct tb_ctl *ctl, void *buffer, u64 route, u32 port,
+		enum tb_cfg_space space, u32 offset, u32 length);
+int tb_cfg_write(struct tb_ctl *ctl, void *buffer, u64 route, u32 port,
+		 enum tb_cfg_space space, u32 offset, u32 length);
+int tb_cfg_get_upstream_port(struct tb_ctl *ctl, u64 route);
+
+
+#endif