| /* |
| * linux/kernel/irq/pm.c |
| * |
| * Copyright (C) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. |
| * |
| * This file contains power management functions related to interrupts. |
| */ |
| |
| #include <linux/irq.h> |
| #include <linux/module.h> |
| #include <linux/interrupt.h> |
| #include <linux/suspend.h> |
| #include <linux/syscore_ops.h> |
| |
| #include "internals.h" |
| |
| bool irq_pm_check_wakeup(struct irq_desc *desc) |
| { |
| if (irqd_is_wakeup_armed(&desc->irq_data)) { |
| irqd_clear(&desc->irq_data, IRQD_WAKEUP_ARMED); |
| desc->istate |= IRQS_SUSPENDED | IRQS_PENDING; |
| desc->depth++; |
| irq_disable(desc); |
| pm_system_irq_wakeup(irq_desc_get_irq(desc)); |
| return true; |
| } |
| return false; |
| } |
| |
| /* |
| * Called from __setup_irq() with desc->lock held after @action has |
| * been installed in the action chain. |
| */ |
| void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) |
| { |
| desc->nr_actions++; |
| |
| if (action->flags & IRQF_FORCE_RESUME) |
| desc->force_resume_depth++; |
| |
| WARN_ON_ONCE(desc->force_resume_depth && |
| desc->force_resume_depth != desc->nr_actions); |
| |
| if (action->flags & IRQF_NO_SUSPEND) |
| desc->no_suspend_depth++; |
| else if (action->flags & IRQF_COND_SUSPEND) |
| desc->cond_suspend_depth++; |
| |
| WARN_ON_ONCE(desc->no_suspend_depth && |
| (desc->no_suspend_depth + |
| desc->cond_suspend_depth) != desc->nr_actions); |
| } |
| |
| /* |
| * Called from __free_irq() with desc->lock held after @action has |
| * been removed from the action chain. |
| */ |
| void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action) |
| { |
| desc->nr_actions--; |
| |
| if (action->flags & IRQF_FORCE_RESUME) |
| desc->force_resume_depth--; |
| |
| if (action->flags & IRQF_NO_SUSPEND) |
| desc->no_suspend_depth--; |
| else if (action->flags & IRQF_COND_SUSPEND) |
| desc->cond_suspend_depth--; |
| } |
| |
| static bool suspend_device_irq(struct irq_desc *desc) |
| { |
| if (!desc->action || irq_desc_is_chained(desc) || |
| desc->no_suspend_depth) |
| return false; |
| |
| if (irqd_is_wakeup_set(&desc->irq_data)) { |
| irqd_set(&desc->irq_data, IRQD_WAKEUP_ARMED); |
| /* |
| * We return true here to force the caller to issue |
| * synchronize_irq(). We need to make sure that the |
| * IRQD_WAKEUP_ARMED is visible before we return from |
| * suspend_device_irqs(). |
| */ |
| return true; |
| } |
| |
| desc->istate |= IRQS_SUSPENDED; |
| __disable_irq(desc); |
| |
| /* |
| * Hardware which has no wakeup source configuration facility |
| * requires that the non wakeup interrupts are masked at the |
| * chip level. The chip implementation indicates that with |
| * IRQCHIP_MASK_ON_SUSPEND. |
| */ |
| if (irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND) |
| mask_irq(desc); |
| return true; |
| } |
| |
| /** |
| * suspend_device_irqs - disable all currently enabled interrupt lines |
| * |
| * During system-wide suspend or hibernation device drivers need to be |
| * prevented from receiving interrupts and this function is provided |
| * for this purpose. |
| * |
| * So we disable all interrupts and mark them IRQS_SUSPENDED except |
| * for those which are unused, those which are marked as not |
| * suspendable via an interrupt request with the flag IRQF_NO_SUSPEND |
| * set and those which are marked as active wakeup sources. |
| * |
| * The active wakeup sources are handled by the flow handler entry |
| * code which checks for the IRQD_WAKEUP_ARMED flag, suspends the |
| * interrupt and notifies the pm core about the wakeup. |
| */ |
| void suspend_device_irqs(void) |
| { |
| struct irq_desc *desc; |
| int irq; |
| |
| for_each_irq_desc(irq, desc) { |
| unsigned long flags; |
| bool sync; |
| |
| if (irq_settings_is_nested_thread(desc)) |
| continue; |
| raw_spin_lock_irqsave(&desc->lock, flags); |
| sync = suspend_device_irq(desc); |
| raw_spin_unlock_irqrestore(&desc->lock, flags); |
| |
| if (sync) |
| synchronize_irq(irq); |
| } |
| } |
| EXPORT_SYMBOL_GPL(suspend_device_irqs); |
| |
| static void resume_irq(struct irq_desc *desc) |
| { |
| irqd_clear(&desc->irq_data, IRQD_WAKEUP_ARMED); |
| |
| if (desc->istate & IRQS_SUSPENDED) |
| goto resume; |
| |
| /* Force resume the interrupt? */ |
| if (!desc->force_resume_depth) |
| return; |
| |
| /* Pretend that it got disabled ! */ |
| desc->depth++; |
| irq_state_set_disabled(desc); |
| irq_state_set_masked(desc); |
| resume: |
| desc->istate &= ~IRQS_SUSPENDED; |
| __enable_irq(desc); |
| } |
| |
| static void resume_irqs(bool want_early) |
| { |
| struct irq_desc *desc; |
| int irq; |
| |
| for_each_irq_desc(irq, desc) { |
| unsigned long flags; |
| bool is_early = desc->action && |
| desc->action->flags & IRQF_EARLY_RESUME; |
| |
| if (!is_early && want_early) |
| continue; |
| if (irq_settings_is_nested_thread(desc)) |
| continue; |
| |
| raw_spin_lock_irqsave(&desc->lock, flags); |
| resume_irq(desc); |
| raw_spin_unlock_irqrestore(&desc->lock, flags); |
| } |
| } |
| |
| /** |
| * irq_pm_syscore_ops - enable interrupt lines early |
| * |
| * Enable all interrupt lines with %IRQF_EARLY_RESUME set. |
| */ |
| static void irq_pm_syscore_resume(void) |
| { |
| resume_irqs(true); |
| } |
| |
| static struct syscore_ops irq_pm_syscore_ops = { |
| .resume = irq_pm_syscore_resume, |
| }; |
| |
| static int __init irq_pm_init_ops(void) |
| { |
| register_syscore_ops(&irq_pm_syscore_ops); |
| return 0; |
| } |
| |
| device_initcall(irq_pm_init_ops); |
| |
| /** |
| * resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs() |
| * |
| * Enable all non-%IRQF_EARLY_RESUME interrupt lines previously |
| * disabled by suspend_device_irqs() that have the IRQS_SUSPENDED flag |
| * set as well as those with %IRQF_FORCE_RESUME. |
| */ |
| void resume_device_irqs(void) |
| { |
| resume_irqs(false); |
| } |
| EXPORT_SYMBOL_GPL(resume_device_irqs); |