// 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_list);static DEFINE_MUTEX(syscore_lock); /** * register_syscore - Register a set of system core operations. * @syscore: System core operations to register. */void register_syscore(struct syscore *syscore){	mutex_lock(&syscore_lock);	list_add_tail(&syscore->node, &syscore_list);	mutex_unlock(&syscore_lock);}EXPORT_SYMBOL_GPL(register_syscore); /** * unregister_syscore - Unregister a set of system core operations. * @syscore: System core operations to unregister. */void unregister_syscore(struct syscore *syscore){	mutex_lock(&syscore_lock);	list_del(&syscore->node);	mutex_unlock(&syscore_lock);}EXPORT_SYMBOL_GPL(unregister_syscore); #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 *syscore;	int ret = 0; 	trace_suspend_resume(TPS("syscore_suspend"), 0, true);	pm_pr_dbg("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(syscore, &syscore_list, node)		if (syscore->ops->suspend) {			pm_pr_dbg("Calling %pS\n", syscore->ops->suspend);			ret = syscore->ops->suspend(syscore->data);			if (ret)				goto err_out;			WARN_ONCE(!irqs_disabled(),				"Interrupts enabled after %pS\n",				syscore->ops->suspend);		} 	trace_suspend_resume(TPS("syscore_suspend"), 0, false);	return 0;  err_out:	pr_err("PM: System core suspend callback %pS failed.\n",	       syscore->ops->suspend); 	list_for_each_entry_continue(syscore, &syscore_list, node)		if (syscore->ops->resume)			syscore->ops->resume(syscore->data); 	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 *syscore; 	trace_suspend_resume(TPS("syscore_resume"), 0, true);	WARN_ONCE(!irqs_disabled(),		"Interrupts enabled before system core resume.\n"); 	list_for_each_entry(syscore, &syscore_list, node)		if (syscore->ops->resume) {			pm_pr_dbg("Calling %pS\n", syscore->ops->resume);			syscore->ops->resume(syscore->data);			WARN_ONCE(!irqs_disabled(),				"Interrupts enabled after %pS\n",				syscore->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 *syscore; 	mutex_lock(&syscore_lock); 	list_for_each_entry_reverse(syscore, &syscore_list, node)		if (syscore->ops->shutdown) {			if (initcall_debug)				pr_info("PM: Calling %pS\n",					syscore->ops->shutdown);			syscore->ops->shutdown(syscore->data);		} 	mutex_unlock(&syscore_lock);}