diff --git a/Documentation/i2c/writing-clients b/Documentation/i2c/writing-clients
index d73ee11..3b01350 100644
--- a/Documentation/i2c/writing-clients
+++ b/Documentation/i2c/writing-clients
@@ -83,7 +83,7 @@
 	void i2c_set_clientdata(struct i2c_client *client, void *data);
 
 	/* retrieve the value */
-	void *i2c_get_clientdata(struct i2c_client *client);
+	void *i2c_get_clientdata(const struct i2c_client *client);
 
 An example structure is below.