USBSACM_PIPE_CLOSED
if ((acm_port->acm_bulkin_state == USBSACM_PIPE_CLOSED) ||
acm_port->acm_bulkin_state = USBSACM_PIPE_CLOSED;
acm_port->acm_bulkout_state = USBSACM_PIPE_CLOSED;
acm_port->acm_intr_state = USBSACM_PIPE_CLOSED;