axen_tick_task
void axen_tick_task(void *);
usb_add_task(sc->axen_udev, &sc->axen_tick_task);
usb_init_task(&sc->axen_tick_task, axen_tick_task, sc,
usb_rem_task(sc->axen_udev, &sc->axen_tick_task);
struct usb_task axen_tick_task;