linux/kernel/irq/pm.c
Laxman Dewangan ac01810c9d irq: Enable all irqs unconditionally in irq_resume
When the system enters suspend, it disables all interrupts in
suspend_device_irqs(), including the interrupts marked EARLY_RESUME.

On the resume side things are different. The EARLY_RESUME interrupts
are reenabled in sys_core_ops->resume and the non EARLY_RESUME
interrupts are reenabled in the normal system resume path.

When suspend_noirq() failed or suspend is aborted for any other
reason, we might omit the resume side call to sys_core_ops->resume()
and therefor the interrupts marked EARLY_RESUME are not reenabled and
stay disabled forever.

To solve this, enable all irqs unconditionally in irq_resume()
regardless whether interrupts marked EARLY_RESUMEhave been already
enabled or not.

This might try to reenable already enabled interrupts in the non
failure case, but the only affected platform is XEN and it has been
confirmed that it does not cause any side effects.

[ tglx: Massaged changelog. ]

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Acked-by-and-tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Pavel Machek <pavel@ucw.cz>
Cc: <ian.campbell@citrix.com>
Cc: <rjw@rjwysocki.net>
Cc: <len.brown@intel.com>
Cc: <gregkh@linuxfoundation.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1385388587-16442-1-git-send-email-ldewangan@nvidia.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-11-25 22:20:02 +01:00

131 lines
3.1 KiB
C

/*
* 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/syscore_ops.h>
#include "internals.h"
/**
* 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.
* It marks all interrupt lines in use, except for the timer ones, as disabled
* and sets the IRQS_SUSPENDED flag for each of them.
*/
void suspend_device_irqs(void)
{
struct irq_desc *desc;
int irq;
for_each_irq_desc(irq, desc) {
unsigned long flags;
raw_spin_lock_irqsave(&desc->lock, flags);
__disable_irq(desc, irq, true);
raw_spin_unlock_irqrestore(&desc->lock, flags);
}
for_each_irq_desc(irq, desc)
if (desc->istate & IRQS_SUSPENDED)
synchronize_irq(irq);
}
EXPORT_SYMBOL_GPL(suspend_device_irqs);
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);
__enable_irq(desc, irq, true);
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);
/**
* check_wakeup_irqs - check if any wake-up interrupts are pending
*/
int check_wakeup_irqs(void)
{
struct irq_desc *desc;
int irq;
for_each_irq_desc(irq, desc) {
/*
* Only interrupts which are marked as wakeup source
* and have not been disabled before the suspend check
* can abort suspend.
*/
if (irqd_is_wakeup_set(&desc->irq_data)) {
if (desc->depth == 1 && desc->istate & IRQS_PENDING)
return -EBUSY;
continue;
}
/*
* Check the non wakeup interrupts whether they need
* to be masked before finally going into suspend
* state. That's for hardware which has no wakeup
* source configuration facility. The chip
* implementation indicates that with
* IRQCHIP_MASK_ON_SUSPEND.
*/
if (desc->istate & IRQS_SUSPENDED &&
irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND)
mask_irq(desc);
}
return 0;
}