// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2009 Rafael J. Wysocki <[email protected]>, 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)
{
unsigned long chipflags = irq_desc_get_chip(desc)->flags;
struct irq_data *irqd = &desc->irq_data;
if (!desc->action || irq_desc_is_chained(desc) ||
desc->no_suspend_depth)
return false;
if (irqd_is_wakeup_set(irqd)) {
irqd_set(irqd, IRQD_WAKEUP_ARMED);
if ((chipflags & IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND) &&
irqd_irq_disabled(irqd)) {
/*
* Interrupt marked for wakeup is in disabled state.
* Enable interrupt here to unmask/enable in irqchip
* to be able to resume with such interrupts.
*/
__enable_irq(desc);
irqd_set(irqd, IRQD_IRQ_ENABLED_ON_SUSPEND);
}
/*
* 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 (chipflags & 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);
}
}
static void resume_irq(struct irq_desc *desc)
{
struct irq_data *irqd = &desc->irq_data;
irqd_clear(irqd, IRQD_WAKEUP_ARMED);
if (irqd_is_enabled_on_suspend(irqd)) {
/*
* Interrupt marked for wakeup was enabled during suspend
* entry. Disable such interrupts to restore them back to
* original state.
*/
__disable_irq(desc);
irqd_clear(irqd, IRQD_IRQ_ENABLED_ON_SUSPEND);
}
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);
}
}
/**
* rearm_wake_irq - rearm a wakeup interrupt line after signaling wakeup
* @irq: Interrupt to rearm
*/
void rearm_wake_irq(unsigned int irq)
{
unsigned long flags;
struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
if (!desc)
return;
if (!(desc->istate & IRQS_SUSPENDED) ||
!irqd_is_wakeup_set(&desc->irq_data))
goto unlock;
desc->istate &= ~IRQS_SUSPENDED;
irqd_set(&desc->irq_data, IRQD_WAKEUP_ARMED);
__enable_irq(desc);
unlock:
irq_put_desc_busunlock(desc, flags);
}
/**
* irq_pm_syscore_resume - 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);
}
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