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 | */ |
21 | void register_syscore_ops(struct syscore_ops *ops) |
22 | { |
23 | mutex_lock(&syscore_ops_lock); |
24 | list_add_tail(new: &ops->node, head: &syscore_ops_list); |
25 | mutex_unlock(lock: &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 | */ |
33 | void unregister_syscore_ops(struct syscore_ops *ops) |
34 | { |
35 | mutex_lock(&syscore_ops_lock); |
36 | list_del(entry: &ops->node); |
37 | mutex_unlock(lock: &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 | */ |
47 | int syscore_suspend(void) |
48 | { |
49 | struct syscore_ops *ops; |
50 | int ret = 0; |
51 | |
52 | trace_suspend_resume(TPS("syscore_suspend" ), val: 0, start: 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" ), val: 0, start: 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 | } |
84 | EXPORT_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 | */ |
91 | void syscore_resume(void) |
92 | { |
93 | struct syscore_ops *ops; |
94 | |
95 | trace_suspend_resume(TPS("syscore_resume" ), val: 0, start: 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" ), val: 0, start: false); |
107 | } |
108 | EXPORT_SYMBOL_GPL(syscore_resume); |
109 | #endif /* CONFIG_PM_SLEEP */ |
110 | |
111 | /** |
112 | * syscore_shutdown - Execute all the registered system core shutdown callbacks. |
113 | */ |
114 | void 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(lock: &syscore_ops_lock); |
128 | } |
129 | |