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