Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 0bd595a..f3b7239 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -1,11 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * kernel/power/suspend.c - Suspend to RAM and standby functionality.
  *
  * Copyright (c) 2003 Patrick Mochel
  * Copyright (c) 2003 Open Source Development Lab
  * Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
- *
- * This file is released under the GPLv2.
  */
 
 #define pr_fmt(fmt) "PM: " fmt
@@ -17,7 +16,6 @@
 #include <linux/console.h>
 #include <linux/cpu.h>
 #include <linux/cpuidle.h>
-#include <linux/syscalls.h>
 #include <linux/gfp.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
@@ -63,11 +61,17 @@
 enum s2idle_states __read_mostly s2idle_state;
 static DEFINE_RAW_SPINLOCK(s2idle_lock);
 
-bool pm_suspend_via_s2idle(void)
+/**
+ * pm_suspend_default_s2idle - Check if suspend-to-idle is the default suspend.
+ *
+ * Return 'true' if suspend-to-idle has been selected as the default system
+ * suspend method.
+ */
+bool pm_suspend_default_s2idle(void)
 {
 	return mem_sleep_current == PM_SUSPEND_TO_IDLE;
 }
-EXPORT_SYMBOL_GPL(pm_suspend_via_s2idle);
+EXPORT_SYMBOL_GPL(pm_suspend_default_s2idle);
 
 void s2idle_set_ops(const struct platform_s2idle_ops *ops)
 {
@@ -117,43 +121,25 @@
 {
 	pm_pr_dbg("suspend-to-idle\n");
 
+	/*
+	 * Suspend-to-idle equals:
+	 * frozen processes + suspended devices + idle processors.
+	 * Thus s2idle_enter() should be called right after all devices have
+	 * been suspended.
+	 *
+	 * Wakeups during the noirq suspend of devices may be spurious, so try
+	 * to avoid them upfront.
+	 */
 	for (;;) {
-		int error;
-
-		dpm_noirq_begin();
-
-		/*
-		 * Suspend-to-idle equals
-		 * frozen processes + suspended devices + idle processors.
-		 * Thus s2idle_enter() should be called right after
-		 * all devices have been suspended.
-		 *
-		 * Wakeups during the noirq suspend of devices may be spurious,
-		 * so prevent them from terminating the loop right away.
-		 */
-		error = dpm_noirq_suspend_devices(PMSG_SUSPEND);
-		if (!error)
-			s2idle_enter();
-		else if (error == -EBUSY && pm_wakeup_pending())
-			error = 0;
-
-		if (!error && s2idle_ops && s2idle_ops->wake)
+		if (s2idle_ops && s2idle_ops->wake)
 			s2idle_ops->wake();
 
-		dpm_noirq_resume_devices(PMSG_RESUME);
-
-		dpm_noirq_end();
-
-		if (error)
-			break;
-
-		if (s2idle_ops && s2idle_ops->sync)
-			s2idle_ops->sync();
-
 		if (pm_wakeup_pending())
 			break;
 
 		pm_wakeup_clear(false);
+
+		s2idle_enter();
 	}
 
 	pm_pr_dbg("resume from suspend-to-idle\n");
@@ -267,14 +253,21 @@
 
 static int platform_suspend_prepare_noirq(suspend_state_t state)
 {
-	return state != PM_SUSPEND_TO_IDLE && suspend_ops->prepare_late ?
-		suspend_ops->prepare_late() : 0;
+	if (state == PM_SUSPEND_TO_IDLE)
+		return s2idle_ops && s2idle_ops->prepare_late ?
+			s2idle_ops->prepare_late() : 0;
+
+	return suspend_ops->prepare_late ? suspend_ops->prepare_late() : 0;
 }
 
 static void platform_resume_noirq(suspend_state_t state)
 {
-	if (state != PM_SUSPEND_TO_IDLE && suspend_ops->wake)
+	if (state == PM_SUSPEND_TO_IDLE) {
+		if (s2idle_ops && s2idle_ops->restore_early)
+			s2idle_ops->restore_early();
+	} else if (suspend_ops->wake) {
 		suspend_ops->wake();
+	}
 }
 
 static void platform_resume_early(suspend_state_t state)
@@ -411,11 +404,6 @@
 	if (error)
 		goto Devices_early_resume;
 
-	if (state == PM_SUSPEND_TO_IDLE && pm_test_level != TEST_PLATFORM) {
-		s2idle_loop();
-		goto Platform_early_resume;
-	}
-
 	error = dpm_suspend_noirq(PMSG_SUSPEND);
 	if (error) {
 		pr_err("noirq suspend of devices failed\n");
@@ -428,7 +416,12 @@
 	if (suspend_test(TEST_PLATFORM))
 		goto Platform_wake;
 
-	error = disable_nonboot_cpus();
+	if (state == PM_SUSPEND_TO_IDLE) {
+		s2idle_loop();
+		goto Platform_wake;
+	}
+
+	error = suspend_disable_secondary_cpus();
 	if (error || suspend_test(TEST_CPUS))
 		goto Enable_cpus;
 
@@ -458,7 +451,7 @@
 	BUG_ON(irqs_disabled());
 
  Enable_cpus:
-	enable_nonboot_cpus();
+	suspend_enable_secondary_cpus();
 
  Platform_wake:
 	platform_resume_noirq(state);
@@ -489,6 +482,9 @@
 
 	pm_suspend_target_state = state;
 
+	if (state == PM_SUSPEND_TO_IDLE)
+		pm_set_suspend_no_platform();
+
 	error = platform_suspend_begin(state);
 	if (error)
 		goto Close;
@@ -568,13 +564,11 @@
 	if (state == PM_SUSPEND_TO_IDLE)
 		s2idle_begin();
 
-#ifndef CONFIG_SUSPEND_SKIP_SYNC
-	trace_suspend_resume(TPS("sync_filesystems"), 0, true);
-	pr_info("Syncing filesystems ... ");
-	ksys_sync();
-	pr_cont("done.\n");
-	trace_suspend_resume(TPS("sync_filesystems"), 0, false);
-#endif
+	if (!IS_ENABLED(CONFIG_SUSPEND_SKIP_SYNC)) {
+		trace_suspend_resume(TPS("sync_filesystems"), 0, true);
+		ksys_sync_helper();
+		trace_suspend_resume(TPS("sync_filesystems"), 0, false);
+	}
 
 	pm_pr_dbg("Preparing system for sleep (%s)\n", mem_sleep_labels[state]);
 	pm_suspend_clear_flags();