diff --git a/drivers/staging/comedi/comedi_compat32.h b/drivers/staging/comedi/comedi_compat32.h
index 5ce77f3e8c22..0127c1f98bbf 100644
--- a/drivers/staging/comedi/comedi_compat32.h
+++ b/drivers/staging/comedi/comedi_compat32.h
@@ -25,7 +25,8 @@
 #ifdef CONFIG_COMPAT
 
 struct file;
-long comedi_compat_ioctl(struct file *, unsigned int cmd, unsigned long arg);
+long comedi_compat_ioctl(struct file *file, unsigned int cmd,
+			 unsigned long arg);
 
 #else /* CONFIG_COMPAT */