Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/net/ieee802154/at86rf230.c b/drivers/net/ieee802154/at86rf230.c
index 3d9e915..7d67f41 100644
--- a/drivers/net/ieee802154/at86rf230.c
+++ b/drivers/net/ieee802154/at86rf230.c
@@ -1,17 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * AT86RF230/RF231 driver
  *
  * Copyright (C) 2009-2012 Siemens AG
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2
- * as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that 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.
- *
  * Written by:
  * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
  * Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
@@ -1632,37 +1624,18 @@
 	seq_printf(file, "INVALID:\t\t%8llu\n", lp->trac.invalid);
 	return 0;
 }
+DEFINE_SHOW_ATTRIBUTE(at86rf230_stats);
 
-static int at86rf230_stats_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, at86rf230_stats_show, inode->i_private);
-}
-
-static const struct file_operations at86rf230_stats_fops = {
-	.open		= at86rf230_stats_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= single_release,
-};
-
-static int at86rf230_debugfs_init(struct at86rf230_local *lp)
+static void at86rf230_debugfs_init(struct at86rf230_local *lp)
 {
 	char debugfs_dir_name[DNAME_INLINE_LEN + 1] = "at86rf230-";
-	struct dentry *stats;
 
 	strncat(debugfs_dir_name, dev_name(&lp->spi->dev), DNAME_INLINE_LEN);
 
 	at86rf230_debugfs_root = debugfs_create_dir(debugfs_dir_name, NULL);
-	if (!at86rf230_debugfs_root)
-		return -ENOMEM;
 
-	stats = debugfs_create_file("trac_stats", 0444,
-				    at86rf230_debugfs_root, lp,
-				    &at86rf230_stats_fops);
-	if (!stats)
-		return -ENOMEM;
-
-	return 0;
+	debugfs_create_file("trac_stats", 0444, at86rf230_debugfs_root, lp,
+			    &at86rf230_stats_fops);
 }
 
 static void at86rf230_debugfs_remove(void)
@@ -1670,7 +1643,7 @@
 	debugfs_remove_recursive(at86rf230_debugfs_root);
 }
 #else
-static int at86rf230_debugfs_init(struct at86rf230_local *lp) { return 0; }
+static void at86rf230_debugfs_init(struct at86rf230_local *lp) { }
 static void at86rf230_debugfs_remove(void) { }
 #endif
 
@@ -1770,9 +1743,7 @@
 	/* going into sleep by default */
 	at86rf230_sleep(lp);
 
-	rc = at86rf230_debugfs_init(lp);
-	if (rc)
-		goto free_dev;
+	at86rf230_debugfs_init(lp);
 
 	rc = ieee802154_register_hw(lp->hw);
 	if (rc)