diff --git a/comedi_calibrate/calib.h b/comedi_calibrate/calib.h
index 2460786..12a1764 100644
--- a/comedi_calibrate/calib.h
+++ b/comedi_calibrate/calib.h
@@ -85,7 +85,7 @@ void reset_caldacs(void);
 
 extern char ni_id[];
 
-void ni_setup(void);
+int ni_setup(void);
 
 /* low level */