diff --git a/drivers/mfd/88pm860x-i2c.c b/drivers/mfd/88pm860x-i2c.c
index 7063cfded6998bb8e8463a5fef71d6f2976b0e77..84e313107233ee8b1e86f0610be093eaa5e1637d 100644
--- a/drivers/mfd/88pm860x-i2c.c
+++ b/drivers/mfd/88pm860x-i2c.c
@@ -122,7 +122,7 @@ static int read_device(struct i2c_client *i2c, int reg,
 static int write_device(struct i2c_client *i2c, int reg,
 			int bytes, void *src)
 {
-	unsigned char buf[bytes + 1];
+	unsigned char buf[2];
 	struct i2c_adapter *adap = i2c->adapter;
 	struct i2c_msg msg;
 	int ret;