// SPDX-License-Identifier: GPL-2.0 /* * syscore.c - Execution of system core operations. * * Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. */ #include <linux/syscore_ops.h> #include <linux/mutex.h> #include <linux/module.h> #include <linux/suspend.h> #include <trace/events/power.h> static LIST_HEAD(syscore_ops_list); static DEFINE_MUTEX(syscore_ops_lock); /** * register_syscore_ops - Register a set of system core operations. * @ops: System core operations to register. */ void register_syscore_ops(struct syscore_ops *ops) { mutex_lock(&syscore_ops_lock); list_add_tail(&ops->node, &syscore_ops_list); mutex_unlock(&syscore_ops_lock); } EXPORT_SYMBOL_GPL(register_syscore_ops); /** * unregister_syscore_ops - Unregister a set of system core operations. * @ops: System core operations to unregister. */ void unregister_syscore_ops(struct syscore_ops *ops) { mutex_lock(&syscore_ops_lock); list_del(&ops->node); mutex_unlock(&syscore_ops_lock); } EXPORT_SYMBOL_GPL(unregister_syscore_ops); #ifdef CONFIG_PM_SLEEP /** * syscore_suspend - Execute all the registered system core suspend callbacks. * * This function is executed with one CPU on-line and disabled interrupts. */ int syscore_suspend(void) { struct syscore_ops *ops; int ret = 0; trace_suspend_resume(TPS("syscore_suspend"), 0, true); pr_debug("Checking wakeup interrupts\n"); /* Return error code if there are any wakeup interrupts pending. */ if (pm_wakeup_pending()) return -EBUSY; WARN_ONCE(!irqs_disabled(), "Interrupts enabled before system core suspend.\n"); list_for_each_entry_reverse(ops, &syscore_ops_list, node) if (ops->suspend) { if (initcall_debug) pr_info("PM: Calling %pS\n", ops->suspend); ret = ops->suspend(); if (ret) goto err_out; WARN_ONCE(!irqs_disabled(), "Interrupts enabled after %pS\n", ops->suspend); } trace_suspend_resume(TPS("syscore_suspend"), 0, false); return 0; err_out: pr_err("PM: System core suspend callback %pS failed.\n", ops->suspend); list_for_each_entry_continue(ops, &syscore_ops_list, node) if (ops->resume) ops->resume(); return ret; } EXPORT_SYMBOL_GPL(syscore_suspend); /** * syscore_resume - Execute all the registered system core resume callbacks. * * This function is executed with one CPU on-line and disabled interrupts. */ void syscore_resume(void) { struct syscore_ops *ops; trace_suspend_resume(TPS("syscore_resume"), 0, true); WARN_ONCE(!irqs_disabled(), "Interrupts enabled before system core resume.\n"); list_for_each_entry(ops, &syscore_ops_list, node) if (ops->resume) { if (initcall_debug) pr_info("PM: Calling %pS\n", ops->resume); ops->resume(); WARN_ONCE(!irqs_disabled(), "Interrupts enabled after %pS\n", ops->resume); } trace_suspend_resume(TPS("syscore_resume"), 0, false); } EXPORT_SYMBOL_GPL(syscore_resume); #endif /* CONFIG_PM_SLEEP */ /** * syscore_shutdown - Execute all the registered system core shutdown callbacks. */ void syscore_shutdown(void) { struct syscore_ops *ops; mutex_lock(&syscore_ops_lock); list_for_each_entry_reverse(ops, &syscore_ops_list, node) if (ops->shutdown) { if (initcall_debug) pr_info("PM: Calling %pS\n", ops->shutdown); ops->shutdown(); } mutex_unlock(&syscore_ops_lock); }