STRUCT 
USB_COMPOSITE(9) Kernel Mode Gadget API STRUCT USB_COMPOSITE(9) NAME
struct_usb_composite_dev - represents one composite usb gadget SYNOPSIS
struct usb_composite_dev { struct usb_gadget * gadget; struct usb_request * req; struct usb_configuration * config; }; MEMBERS
gadget read-only, abstracts the gadget's usb peripheral controller req used for control responses; buffer is pre-allocated config the currently active configuration DESCRIPTION
One of these devices is allocated and initialized before the associated device driver's bind is called. OPEN ISSUE
it appears that some WUSB devices will need to be built by combining a normal (wired) gadget with a wireless one. This revision of the gadget framework should probably try to make sure doing that won't hurt too much. ONE NOTION FOR HOW TO HANDLE WIRELESS USB DEVICES INVOLVES
(a) a second gadget here, discovery mechanism TBD, but likely needing separate "register/unregister WUSB gadget" calls; (b) updates to usb_gadget to include flags "is it wireless", "is it wired", plus (presumably in a wrapper structure) bandgroup and PHY info; (c) presumably a wireless_ep wrapping a usb_ep, and reporting wireless-specific parameters like maxburst and maxsequence; (d) configurations that are specific to wireless links; (e) function drivers that understand wireless configs and will support wireless for (additional) function instances; (f) a function to support association setup (like CBAF), not necessarily requiring a wireless adapter; (g) composite device setup that can create one or more wireless configs, including appropriate association setup support; (h) more, TBD. AUTHOR
David Brownell <dbrownell@users.sourceforge.net> Author. COPYRIGHT
Kernel Hackers Manual 3.10 June 2014 STRUCT USB_COMPOSITE(9)