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(&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 */ 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 */ 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 */ 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 */ 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