1/*
2 *  syscore.c - Execution of system core operations.
3 *
4 *  Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
5 *
6 *  This file is released under the GPLv2.
7 */
8
9#include <linux/syscore_ops.h>
10#include <linux/mutex.h>
11#include <linux/module.h>
12#include <linux/suspend.h>
13#include <trace/events/power.h>
14#include <linux/wakeup_reason.h>
15
16static LIST_HEAD(syscore_ops_list);
17static DEFINE_MUTEX(syscore_ops_lock);
18
19/**
20 * register_syscore_ops - Register a set of system core operations.
21 * @ops: System core operations to register.
22 */
23void register_syscore_ops(struct syscore_ops *ops)
24{
25	mutex_lock(&syscore_ops_lock);
26	list_add_tail(&ops->node, &syscore_ops_list);
27	mutex_unlock(&syscore_ops_lock);
28}
29EXPORT_SYMBOL_GPL(register_syscore_ops);
30
31/**
32 * unregister_syscore_ops - Unregister a set of system core operations.
33 * @ops: System core operations to unregister.
34 */
35void unregister_syscore_ops(struct syscore_ops *ops)
36{
37	mutex_lock(&syscore_ops_lock);
38	list_del(&ops->node);
39	mutex_unlock(&syscore_ops_lock);
40}
41EXPORT_SYMBOL_GPL(unregister_syscore_ops);
42
43#ifdef CONFIG_PM_SLEEP
44/**
45 * syscore_suspend - Execute all the registered system core suspend callbacks.
46 *
47 * This function is executed with one CPU on-line and disabled interrupts.
48 */
49int syscore_suspend(void)
50{
51	struct syscore_ops *ops;
52	int ret = 0;
53
54	trace_suspend_resume(TPS("syscore_suspend"), 0, true);
55	pr_debug("Checking wakeup interrupts\n");
56
57	/* Return error code if there are any wakeup interrupts pending. */
58	if (pm_wakeup_pending())
59		return -EBUSY;
60
61	WARN_ONCE(!irqs_disabled(),
62		"Interrupts enabled before system core suspend.\n");
63
64	list_for_each_entry_reverse(ops, &syscore_ops_list, node)
65		if (ops->suspend) {
66			if (initcall_debug)
67				pr_info("PM: Calling %pF\n", ops->suspend);
68			ret = ops->suspend();
69			if (ret)
70				goto err_out;
71			WARN_ONCE(!irqs_disabled(),
72				"Interrupts enabled after %pF\n", ops->suspend);
73		}
74
75	trace_suspend_resume(TPS("syscore_suspend"), 0, false);
76	return 0;
77
78 err_out:
79	log_suspend_abort_reason("System core suspend callback %pF failed",
80		ops->suspend);
81	pr_err("PM: System core suspend callback %pF failed.\n", ops->suspend);
82
83	list_for_each_entry_continue(ops, &syscore_ops_list, node)
84		if (ops->resume)
85			ops->resume();
86
87	return ret;
88}
89EXPORT_SYMBOL_GPL(syscore_suspend);
90
91/**
92 * syscore_resume - Execute all the registered system core resume callbacks.
93 *
94 * This function is executed with one CPU on-line and disabled interrupts.
95 */
96void syscore_resume(void)
97{
98	struct syscore_ops *ops;
99
100	trace_suspend_resume(TPS("syscore_resume"), 0, true);
101	WARN_ONCE(!irqs_disabled(),
102		"Interrupts enabled before system core resume.\n");
103
104	list_for_each_entry(ops, &syscore_ops_list, node)
105		if (ops->resume) {
106			if (initcall_debug)
107				pr_info("PM: Calling %pF\n", ops->resume);
108			ops->resume();
109			WARN_ONCE(!irqs_disabled(),
110				"Interrupts enabled after %pF\n", ops->resume);
111		}
112	trace_suspend_resume(TPS("syscore_resume"), 0, false);
113}
114EXPORT_SYMBOL_GPL(syscore_resume);
115#endif /* CONFIG_PM_SLEEP */
116
117/**
118 * syscore_shutdown - Execute all the registered system core shutdown callbacks.
119 */
120void syscore_shutdown(void)
121{
122	struct syscore_ops *ops;
123
124	mutex_lock(&syscore_ops_lock);
125
126	list_for_each_entry_reverse(ops, &syscore_ops_list, node)
127		if (ops->shutdown) {
128			if (initcall_debug)
129				pr_info("PM: Calling %pF\n", ops->shutdown);
130			ops->shutdown();
131		}
132
133	mutex_unlock(&syscore_ops_lock);
134}
135