Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/mailbox/mailbox-altera.c b/drivers/mailbox/mailbox-altera.c
index bcb29df..7528266 100644
--- a/drivers/mailbox/mailbox-altera.c
+++ b/drivers/mailbox/mailbox-altera.c
@@ -1,17 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright Altera Corporation (C) 2013-2014. All rights reserved
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * This program is distributed in the hope it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 #include <linux/device.h>
@@ -341,7 +330,7 @@
 		}
 	}
 
-	ret = mbox_controller_register(&mbox->controller);
+	ret = devm_mbox_controller_register(&pdev->dev, &mbox->controller);
 	if (ret) {
 		dev_err(&pdev->dev, "Register mailbox failed\n");
 		goto err;
@@ -352,18 +341,6 @@
 	return ret;
 }
 
-static int altera_mbox_remove(struct platform_device *pdev)
-{
-	struct altera_mbox *mbox = platform_get_drvdata(pdev);
-
-	if (!mbox)
-		return -EINVAL;
-
-	mbox_controller_unregister(&mbox->controller);
-
-	return 0;
-}
-
 static const struct of_device_id altera_mbox_match[] = {
 	{ .compatible = "altr,mailbox-1.0" },
 	{ /* Sentinel */ }
@@ -373,7 +350,6 @@
 
 static struct platform_driver altera_mbox_driver = {
 	.probe	= altera_mbox_probe,
-	.remove	= altera_mbox_remove,
 	.driver	= {
 		.name	= DRIVER_NAME,
 		.of_match_table	= altera_mbox_match,