free_usb_request
struct usb_request *request __free(free_usb_request) = NULL;
struct usb_request *request __free(free_usb_request) = NULL;
struct usb_request *request __free(free_usb_request) = NULL;
struct usb_request *request __free(free_usb_request) = NULL;
DEFINE_FREE(free_usb_request, struct usb_request *, free_usb_request(_T))