dfu:usb: Support for g_dnl composite download gadget.

Composite USB download gadget support (g_dnl) for download functions.
This code works on top of composite gadget.

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Marek Vasut <marex@denx.de>

include/g_dnl.h

@@ -0,0 +1,33 @@
+/*
+ *  Copyright (C) 2012 Samsung Electronics
+ *  Lukasz Majewski <l.majewski@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef __G_DOWNLOAD_H_
+#define __G_DOWNLOAD_H_
+
+#include <linux/usb/ch9.h>
+#include <usbdescriptors.h>
+#include <linux/usb/gadget.h>
+
+int g_dnl_register(const char *s);
+void g_dnl_unregister(void);
+
+/* USB initialization declaration - board specific */
+void board_usb_init(void);
+#endif /* __G_DOWNLOAD_H_ */