diff --git a/drivers/w1/w1.h b/drivers/w1/w1.h
index 6cc7f0c..d890078 100644
--- a/drivers/w1/w1.h
+++ b/drivers/w1/w1.h
@@ -75,6 +75,7 @@
 
 	struct w1_master	*master;
 	struct w1_family	*family;
+	void			*family_data;
 	struct device		dev;
 	struct completion	released;
 };