diff --git a/drivers/mfd/cros_ec_i2c.c b/drivers/mfd/cros_ec_i2c.c
index fbf7819..b400bfa 100644
--- a/drivers/mfd/cros_ec_i2c.c
+++ b/drivers/mfd/cros_ec_i2c.c
@@ -143,8 +143,12 @@
 	ec_dev->priv = client;
 	ec_dev->irq = client->irq;
 	ec_dev->cmd_xfer = cros_ec_cmd_xfer_i2c;
+	ec_dev->pkt_xfer = NULL;
 	ec_dev->ec_name = client->name;
 	ec_dev->phys_name = client->adapter->name;
+	ec_dev->din_size = sizeof(struct ec_host_response) +
+			   sizeof(struct ec_response_get_protocol_info);
+	ec_dev->dout_size = sizeof(struct ec_host_request);
 
 	err = cros_ec_register(ec_dev);
 	if (err) {