Index: uspace/lib/usb/include/usb/hcd.h
===================================================================
--- uspace/lib/usb/include/usb/hcd.h	(revision 3f45993eb7dca245d8cf7a8185f179b4537df8d3)
+++ uspace/lib/usb/include/usb/hcd.h	(revision 3f45993eb7dca245d8cf7a8185f179b4537df8d3)
@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2010 Vojtech Horky
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/** @addtogroup libusb usb
+ * @{
+ */
+/** @file
+ * @brief HC driver.
+ */
+#ifndef LIBUSB_HCD_H_
+#define LIBUSB_HCD_H_
+
+#include <usb/usb.h>
+#include <fibril_synch.h>
+#include <devman.h>
+
+/** Info about used address. */
+typedef struct {
+	/** Linked list member. */
+	link_t link;
+	/** Address. */
+	usb_address_t address;
+	/** Corresponding devman handle. */
+	devman_handle_t devman_handle;
+} usb_address_keeping_used_t;
+
+/** Structure for keeping track of free and used USB addresses. */
+typedef struct {
+	/** Head of list of used addresses. */
+	link_t used_addresses;
+	/** Upper bound for USB addresses. */
+	usb_address_t max_address;
+	/** Mutex protecting used address. */
+	fibril_mutex_t used_addresses_guard;
+	/** Condition variable for used addresses. */
+	fibril_condvar_t used_addresses_condvar;
+
+	/** Condition variable mutex for default address. */
+	fibril_mutex_t default_condvar_guard;
+	/** Condition variable for default address. */
+	fibril_condvar_t default_condvar;
+	/** Whether is default address available. */
+	bool default_available;
+} usb_address_keeping_t;
+
+void usb_address_keeping_init(usb_address_keeping_t *, usb_address_t);
+
+void usb_address_keeping_reserve_default(usb_address_keeping_t *);
+void usb_address_keeping_release_default(usb_address_keeping_t *);
+
+usb_address_t usb_address_keeping_request(usb_address_keeping_t *);
+int usb_address_keeping_release(usb_address_keeping_t *, usb_address_t);
+void usb_address_keeping_devman_bind(usb_address_keeping_t *, usb_address_t,
+    devman_handle_t);
+usb_address_t usb_address_keeping_find(usb_address_keeping_t *,
+    devman_handle_t);
+
+
+#endif