Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/kernel/power/main.c b/kernel/power/main.c
index 35b5082..e26de7a 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -1,11 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * kernel/power/main.c - PM subsystem core functionality.
  *
  * Copyright (c) 2003 Patrick Mochel
  * Copyright (c) 2003 Open Source Development Lab
- *
- * This file is released under the GPLv2
- *
  */
 
 #include <linux/export.h>
@@ -16,6 +14,8 @@
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #include <linux/suspend.h>
+#include <linux/syscalls.h>
+#include <linux/pm_runtime.h>
 
 #include "power.h"
 
@@ -51,6 +51,19 @@
 }
 EXPORT_SYMBOL_GPL(unlock_system_sleep);
 
+void ksys_sync_helper(void)
+{
+	ktime_t start;
+	long elapsed_msecs;
+
+	start = ktime_get();
+	ksys_sync();
+	elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start));
+	pr_info("Filesystems sync: %ld.%03ld seconds\n",
+		elapsed_msecs / MSEC_PER_SEC, elapsed_msecs % MSEC_PER_SEC);
+}
+EXPORT_SYMBOL_GPL(ksys_sync_helper);
+
 /* Routines for PM-transition notifications */
 
 static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
@@ -242,7 +255,6 @@
 power_attr(pm_test);
 #endif /* CONFIG_PM_SLEEP_DEBUG */
 
-#ifdef CONFIG_DEBUG_FS
 static char *suspend_step_name(enum suspend_stat_step step)
 {
 	switch (step) {
@@ -263,6 +275,92 @@
 	}
 }
 
+#define suspend_attr(_name)					\
+static ssize_t _name##_show(struct kobject *kobj,		\
+		struct kobj_attribute *attr, char *buf)		\
+{								\
+	return sprintf(buf, "%d\n", suspend_stats._name);	\
+}								\
+static struct kobj_attribute _name = __ATTR_RO(_name)
+
+suspend_attr(success);
+suspend_attr(fail);
+suspend_attr(failed_freeze);
+suspend_attr(failed_prepare);
+suspend_attr(failed_suspend);
+suspend_attr(failed_suspend_late);
+suspend_attr(failed_suspend_noirq);
+suspend_attr(failed_resume);
+suspend_attr(failed_resume_early);
+suspend_attr(failed_resume_noirq);
+
+static ssize_t last_failed_dev_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	int index;
+	char *last_failed_dev = NULL;
+
+	index = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
+	index %= REC_FAILED_NUM;
+	last_failed_dev = suspend_stats.failed_devs[index];
+
+	return sprintf(buf, "%s\n", last_failed_dev);
+}
+static struct kobj_attribute last_failed_dev = __ATTR_RO(last_failed_dev);
+
+static ssize_t last_failed_errno_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	int index;
+	int last_failed_errno;
+
+	index = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
+	index %= REC_FAILED_NUM;
+	last_failed_errno = suspend_stats.errno[index];
+
+	return sprintf(buf, "%d\n", last_failed_errno);
+}
+static struct kobj_attribute last_failed_errno = __ATTR_RO(last_failed_errno);
+
+static ssize_t last_failed_step_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	int index;
+	enum suspend_stat_step step;
+	char *last_failed_step = NULL;
+
+	index = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
+	index %= REC_FAILED_NUM;
+	step = suspend_stats.failed_steps[index];
+	last_failed_step = suspend_step_name(step);
+
+	return sprintf(buf, "%s\n", last_failed_step);
+}
+static struct kobj_attribute last_failed_step = __ATTR_RO(last_failed_step);
+
+static struct attribute *suspend_attrs[] = {
+	&success.attr,
+	&fail.attr,
+	&failed_freeze.attr,
+	&failed_prepare.attr,
+	&failed_suspend.attr,
+	&failed_suspend_late.attr,
+	&failed_suspend_noirq.attr,
+	&failed_resume.attr,
+	&failed_resume_early.attr,
+	&failed_resume_noirq.attr,
+	&last_failed_dev.attr,
+	&last_failed_errno.attr,
+	&last_failed_step.attr,
+	NULL,
+};
+
+static struct attribute_group suspend_attr_group = {
+	.name = "suspend_stats",
+	.attrs = suspend_attrs,
+};
+
+#ifdef CONFIG_DEBUG_FS
 static int suspend_stats_show(struct seq_file *s, void *unused)
 {
 	int i, index, last_dev, last_errno, last_step;
@@ -318,23 +416,12 @@
 
 	return 0;
 }
-
-static int suspend_stats_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, suspend_stats_show, NULL);
-}
-
-static const struct file_operations suspend_stats_operations = {
-	.open           = suspend_stats_open,
-	.read           = seq_read,
-	.llseek         = seq_lseek,
-	.release        = single_release,
-};
+DEFINE_SHOW_ATTRIBUTE(suspend_stats);
 
 static int __init pm_debugfs_init(void)
 {
 	debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO,
-			NULL, NULL, &suspend_stats_operations);
+			NULL, NULL, &suspend_stats_fops);
 	return 0;
 }
 
@@ -494,7 +581,7 @@
 	len = p ? p - buf : n;
 
 	/* Check hibernation first. */
-	if (len == 4 && !strncmp(buf, "disk", len))
+	if (len == 4 && str_has_prefix(buf, "disk"))
 		return PM_SUSPEND_MAX;
 
 #ifdef CONFIG_SUSPEND
@@ -793,6 +880,14 @@
 	.attrs = g,
 };
 
+static const struct attribute_group *attr_groups[] = {
+	&attr_group,
+#ifdef CONFIG_PM_SLEEP
+	&suspend_attr_group,
+#endif
+	NULL,
+};
+
 struct workqueue_struct *pm_wq;
 EXPORT_SYMBOL_GPL(pm_wq);
 
@@ -814,7 +909,7 @@
 	power_kobj = kobject_create_and_add("power", NULL);
 	if (!power_kobj)
 		return -ENOMEM;
-	error = sysfs_create_group(power_kobj, &attr_group);
+	error = sysfs_create_groups(power_kobj, attr_groups);
 	if (error)
 		return error;
 	pm_print_times_init();