Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/include/linux/devfreq-event.h b/include/linux/devfreq-event.h
index 4db00b0..f14f17f 100644
--- a/include/linux/devfreq-event.h
+++ b/include/linux/devfreq-event.h
@@ -1,12 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * devfreq-event: a framework to provide raw data and events of devfreq devices
  *
  * Copyright (C) 2014 Samsung Electronics
  * Author: Chanwoo Choi <cw00.choi@samsung.com>
- *
- * 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.
  */
 
 #ifndef __LINUX_DEVFREQ_EVENT_H__
@@ -81,14 +78,20 @@
  * struct devfreq_event_desc - the descriptor of devfreq-event device
  *
  * @name	: the name of devfreq-event device.
+ * @event_type	: the type of the event determined and used by driver
  * @driver_data	: the private data for devfreq-event driver.
  * @ops		: the operation to control devfreq-event device.
  *
  * Each devfreq-event device is described with a this structure.
  * This structure contains the various data for devfreq-event device.
+ * The event_type describes what is going to be counted in the register.
+ * It might choose to count e.g. read requests, write data in bytes, etc.
+ * The full supported list of types is present in specyfic header in:
+ * include/dt-bindings/pmu/.
  */
 struct devfreq_event_desc {
 	const char *name;
+	u32 event_type;
 	void *driver_data;
 
 	const struct devfreq_event_ops *ops;