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 #include <linux/wakeup_reason.h>
14
15 static LIST_HEAD(syscore_ops_list);
16 static 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 */
register_syscore_ops(struct syscore_ops * ops)22 void 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 }
28 EXPORT_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 */
unregister_syscore_ops(struct syscore_ops * ops)34 void 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 }
40 EXPORT_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 */
syscore_suspend(void)48 int syscore_suspend(void)
49 {
50 struct syscore_ops *ops;
51 int ret = 0;
52
53 trace_suspend_resume(TPS("syscore_suspend"), 0, true);
54 pm_pr_dbg("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 pm_pr_dbg("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 log_suspend_abort_reason("System core suspend callback %pS failed",
78 ops->suspend);
79 pr_err("PM: System core suspend callback %pF failed.\n", ops->suspend);
80
81 list_for_each_entry_continue(ops, &syscore_ops_list, node)
82 if (ops->resume)
83 ops->resume();
84
85 return ret;
86 }
87 EXPORT_SYMBOL_GPL(syscore_suspend);
88
89 /**
90 * syscore_resume - Execute all the registered system core resume callbacks.
91 *
92 * This function is executed with one CPU on-line and disabled interrupts.
93 */
syscore_resume(void)94 void syscore_resume(void)
95 {
96 struct syscore_ops *ops;
97
98 trace_suspend_resume(TPS("syscore_resume"), 0, true);
99 WARN_ONCE(!irqs_disabled(),
100 "Interrupts enabled before system core resume.\n");
101
102 list_for_each_entry(ops, &syscore_ops_list, node)
103 if (ops->resume) {
104 pm_pr_dbg("Calling %pS\n", ops->resume);
105 ops->resume();
106 WARN_ONCE(!irqs_disabled(),
107 "Interrupts enabled after %pS\n", ops->resume);
108 }
109 trace_suspend_resume(TPS("syscore_resume"), 0, false);
110 }
111 EXPORT_SYMBOL_GPL(syscore_resume);
112 #endif /* CONFIG_PM_SLEEP */
113
114 /**
115 * syscore_shutdown - Execute all the registered system core shutdown callbacks.
116 */
syscore_shutdown(void)117 void 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 %pS\n", ops->shutdown);
127 ops->shutdown();
128 }
129
130 mutex_unlock(&syscore_ops_lock);
131 }
132