1// SPDX-License-Identifier: GPL-2.0
2/*
3 *  syscore.c - Execution of system core operations.
4 *
5 *  Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
6 */
7
8#include <linux/syscore_ops.h>
9#include <linux/mutex.h>
10#include <linux/module.h>
11#include <linux/suspend.h>
12#include <trace/events/power.h>
13
14static LIST_HEAD(syscore_ops_list);
15static DEFINE_MUTEX(syscore_ops_lock);
16
17/**
18 * register_syscore_ops - Register a set of system core operations.
19 * @ops: System core operations to register.
20 */
21void register_syscore_ops(struct syscore_ops *ops)
22{
23	mutex_lock(&syscore_ops_lock);
24	list_add_tail(&ops->node, &syscore_ops_list);
25	mutex_unlock(&syscore_ops_lock);
26}
27EXPORT_SYMBOL_GPL(register_syscore_ops);
28
29/**
30 * unregister_syscore_ops - Unregister a set of system core operations.
31 * @ops: System core operations to unregister.
32 */
33void unregister_syscore_ops(struct syscore_ops *ops)
34{
35	mutex_lock(&syscore_ops_lock);
36	list_del(&ops->node);
37	mutex_unlock(&syscore_ops_lock);
38}
39EXPORT_SYMBOL_GPL(unregister_syscore_ops);
40
41#ifdef CONFIG_PM_SLEEP
42/**
43 * syscore_suspend - Execute all the registered system core suspend callbacks.
44 *
45 * This function is executed with one CPU on-line and disabled interrupts.
46 */
47int syscore_suspend(void)
48{
49	struct syscore_ops *ops;
50	int ret = 0;
51
52	trace_suspend_resume(TPS("syscore_suspend"), 0, true);
53	pm_pr_dbg("Checking wakeup interrupts\n");
54
55	/* Return error code if there are any wakeup interrupts pending. */
56	if (pm_wakeup_pending())
57		return -EBUSY;
58
59	WARN_ONCE(!irqs_disabled(),
60		"Interrupts enabled before system core suspend.\n");
61
62	list_for_each_entry_reverse(ops, &syscore_ops_list, node)
63		if (ops->suspend) {
64			pm_pr_dbg("Calling %pS\n", ops->suspend);
65			ret = ops->suspend();
66			if (ret)
67				goto err_out;
68			WARN_ONCE(!irqs_disabled(),
69				"Interrupts enabled after %pS\n", ops->suspend);
70		}
71
72	trace_suspend_resume(TPS("syscore_suspend"), 0, false);
73	return 0;
74
75 err_out:
76	pr_err("PM: System core suspend callback %pS failed.\n", ops->suspend);
77
78	list_for_each_entry_continue(ops, &syscore_ops_list, node)
79		if (ops->resume)
80			ops->resume();
81
82	return ret;
83}
84EXPORT_SYMBOL_GPL(syscore_suspend);
85
86/**
87 * syscore_resume - Execute all the registered system core resume callbacks.
88 *
89 * This function is executed with one CPU on-line and disabled interrupts.
90 */
91void syscore_resume(void)
92{
93	struct syscore_ops *ops;
94
95	trace_suspend_resume(TPS("syscore_resume"), 0, true);
96	WARN_ONCE(!irqs_disabled(),
97		"Interrupts enabled before system core resume.\n");
98
99	list_for_each_entry(ops, &syscore_ops_list, node)
100		if (ops->resume) {
101			pm_pr_dbg("Calling %pS\n", ops->resume);
102			ops->resume();
103			WARN_ONCE(!irqs_disabled(),
104				"Interrupts enabled after %pS\n", ops->resume);
105		}
106	trace_suspend_resume(TPS("syscore_resume"), 0, false);
107}
108EXPORT_SYMBOL_GPL(syscore_resume);
109#endif /* CONFIG_PM_SLEEP */
110
111/**
112 * syscore_shutdown - Execute all the registered system core shutdown callbacks.
113 */
114void syscore_shutdown(void)
115{
116	struct syscore_ops *ops;
117
118	mutex_lock(&syscore_ops_lock);
119
120	list_for_each_entry_reverse(ops, &syscore_ops_list, node)
121		if (ops->shutdown) {
122			if (initcall_debug)
123				pr_info("PM: Calling %pS\n", ops->shutdown);
124			ops->shutdown();
125		}
126
127	mutex_unlock(&syscore_ops_lock);
128}
129