--- /dev/null
+/*
+ * 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_wakeup();
+ 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, int irq)
+{
+ if (!desc->action || 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, irq);
+
+ /*
+ * 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;
+
+ raw_spin_lock_irqsave(&desc->lock, flags);
+ sync = suspend_device_irq(desc, irq);
+ 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, int irq)
+{
+ 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++;
+resume:
+ desc->istate &= ~IRQS_SUSPENDED;
+ __enable_irq(desc, irq);
+}
+
+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;
+
+ raw_spin_lock_irqsave(&desc->lock, flags);
+ resume_irq(desc, irq);
+ 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);
Code Review / kvmfornfv.git / blobdiff