Root/drivers/base/syscore.c

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/interrupt.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    pr_debug("Checking wakeup interrupts\n");
53
54    /* Return error code if there are any wakeup interrupts pending. */
55    ret = check_wakeup_irqs();
56    if (ret)
57        return ret;
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            if (initcall_debug)
65                pr_info("PM: Calling %pF\n", ops->suspend);
66            ret = ops->suspend();
67            if (ret)
68                goto err_out;
69            WARN_ONCE(!irqs_disabled(),
70                "Interrupts enabled after %pF\n", ops->suspend);
71        }
72
73    return 0;
74
75 err_out:
76    pr_err("PM: System core suspend callback %pF 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    WARN_ONCE(!irqs_disabled(),
96        "Interrupts enabled before system core resume.\n");
97
98    list_for_each_entry(ops, &syscore_ops_list, node)
99        if (ops->resume) {
100            if (initcall_debug)
101                pr_info("PM: Calling %pF\n", ops->resume);
102            ops->resume();
103            WARN_ONCE(!irqs_disabled(),
104                "Interrupts enabled after %pF\n", ops->resume);
105        }
106}
107EXPORT_SYMBOL_GPL(syscore_resume);
108#endif /* CONFIG_PM_SLEEP */
109
110/**
111 * syscore_shutdown - Execute all the registered system core shutdown callbacks.
112 */
113void syscore_shutdown(void)
114{
115    struct syscore_ops *ops;
116
117    mutex_lock(&syscore_ops_lock);
118
119    list_for_each_entry_reverse(ops, &syscore_ops_list, node)
120        if (ops->shutdown) {
121            if (initcall_debug)
122                pr_info("PM: Calling %pF\n", ops->shutdown);
123            ops->shutdown();
124        }
125
126    mutex_unlock(&syscore_ops_lock);
127}
128

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