dirty_freerun_ceiling
unsigned long freerun = dirty_freerun_ceiling(dtc->thresh, dtc->bg_thresh);
wb_setpoint = dirty_freerun_ceiling(wb_thresh,
unsigned long freerun = dirty_freerun_ceiling(dtc->thresh, dtc->bg_thresh);
dtc->freerun = dirty <= dirty_freerun_ceiling(thresh, bg_thresh);
dirty_freerun_ceiling(dtc->wb_thresh, dtc->wb_bg_thresh);