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
14 static LIST_HEAD(syscore_ops_list);
15 static 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 */
register_syscore_ops(struct syscore_ops * ops)21 void 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 }
27 EXPORT_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 */
unregister_syscore_ops(struct syscore_ops * ops)33 void 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 }
39 EXPORT_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 */
syscore_suspend(void)47 int syscore_suspend(void)
48 {
49 struct syscore_ops *ops;
50 int ret = 0;
51
52 trace_suspend_resume(TPS("syscore_suspend"), 0, true);
53 pr_debug("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 if (initcall_debug)
65 pr_info("PM: Calling %pS\n", ops->suspend);
66 ret = ops->suspend();
67 if (ret)
68 goto err_out;
69 WARN_ONCE(!irqs_disabled(),
70 "Interrupts enabled after %pS\n", ops->suspend);
71 }
72
73 trace_suspend_resume(TPS("syscore_suspend"), 0, false);
74 return 0;
75
76 err_out:
77 pr_err("PM: System core suspend callback %pS failed.\n", ops->suspend);
78
79 list_for_each_entry_continue(ops, &syscore_ops_list, node)
80 if (ops->resume)
81 ops->resume();
82
83 return ret;
84 }
85 EXPORT_SYMBOL_GPL(syscore_suspend);
86
87 /**
88 * syscore_resume - Execute all the registered system core resume callbacks.
89 *
90 * This function is executed with one CPU on-line and disabled interrupts.
91 */
syscore_resume(void)92 void syscore_resume(void)
93 {
94 struct syscore_ops *ops;
95
96 trace_suspend_resume(TPS("syscore_resume"), 0, true);
97 WARN_ONCE(!irqs_disabled(),
98 "Interrupts enabled before system core resume.\n");
99
100 list_for_each_entry(ops, &syscore_ops_list, node)
101 if (ops->resume) {
102 if (initcall_debug)
103 pr_info("PM: Calling %pS\n", ops->resume);
104 ops->resume();
105 WARN_ONCE(!irqs_disabled(),
106 "Interrupts enabled after %pS\n", ops->resume);
107 }
108 trace_suspend_resume(TPS("syscore_resume"), 0, false);
109 }
110 EXPORT_SYMBOL_GPL(syscore_resume);
111 #endif /* CONFIG_PM_SLEEP */
112
113 /**
114 * syscore_shutdown - Execute all the registered system core shutdown callbacks.
115 */
syscore_shutdown(void)116 void syscore_shutdown(void)
117 {
118 struct syscore_ops *ops;
119
120 mutex_lock(&syscore_ops_lock);
121
122 list_for_each_entry_reverse(ops, &syscore_ops_list, node)
123 if (ops->shutdown) {
124 if (initcall_debug)
125 pr_info("PM: Calling %pS\n", ops->shutdown);
126 ops->shutdown();
127 }
128
129 mutex_unlock(&syscore_ops_lock);
130 }
131
