suse man page for usb_add_function

USB_ADD_FUNCTION(9)					      Kernel Mode Gadget API					       USB_ADD_FUNCTION(9)

NAME
       usb_add_function - add a function to a configuration

SYNOPSIS
       int usb_add_function(struct usb_configuration * config, struct usb_function * function);

ARGUMENTS
       config
	   the configuration

       function
	   the function being added

CONTEXT
       single threaded during gadget setup

DESCRIPTION
       After initialization, each configuration must have one or more functions added to it. Adding a function involves calling its bind() method
       to allocate resources such as interface and string identifiers and endpoints.

       This function returns the value of the function's bind, which is zero for success else a negative errno value.

AUTHOR
       David Brownell <dbrownell@users.sourceforge.net>
	   Author.

COPYRIGHT
Kernel Hackers Manual 2.6.					     July 2010						       USB_ADD_FUNCTION(9)