1. 根目录:
2. drivers
3. usb
4. gadget
5. configfs.h

#ifndef USB__GADGET__CONFIGFS__H
#define USB__GADGET__CONFIGFS__H

#include <linux/configfs.h>

void unregister_gadget_item(struct config_item *item);

int usb_os_desc_prepare_interf_dir(struct config_group *parent,
				   int n_interf,
				   struct usb_os_desc **desc,
				   char **names,
				   struct module *owner);

static inline struct usb_os_desc *to_usb_os_desc(struct config_item *item)
{
	return container_of(to_config_group(item), struct usb_os_desc, group);
}

#endif /*  USB__GADGET__CONFIGFS__H */