diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 06115128047f..4ac8ec3c7927 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -345,7 +345,7 @@ struct i2c_algorithm {
 struct i2c_adapter {
 	struct module *owner;
 	unsigned int id;
-	unsigned int class;
+	unsigned int class;		  /* classes to allow probing for */
 	const struct i2c_algorithm *algo; /* the algorithm to access the bus */
 	void *algo_data;