[linux.git] / kernel / irq / pm.c

/*
 * linux/kernel/irq/pm.c
 *
 * 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 "internals.h"

/**
 * suspend_device_irqs - disable all currently enabled interrupt lines
 *
 * During system-wide suspend or hibernation device interrupts need to be
 * disabled at the chip level and this function is provided for this purpose.
 * It disables all interrupt lines that are enabled at the moment and sets the
 * IRQ_SUSPENDED flag for them.
 */
void suspend_device_irqs(void)
{
	struct irq_desc *desc;
	int irq;

	for_each_irq_desc(irq, desc) {
		unsigned long flags;

		spin_lock_irqsave(&desc->lock, flags);
		__disable_irq(desc, irq, true);
		spin_unlock_irqrestore(&desc->lock, flags);
	}

	for_each_irq_desc(irq, desc)
		if (desc->status & IRQ_SUSPENDED)
			synchronize_irq(irq);
}
EXPORT_SYMBOL_GPL(suspend_device_irqs);

/**
 * resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs()
 *
 * Enable all interrupt lines previously disabled by suspend_device_irqs() that
 * have the IRQ_SUSPENDED flag set.
 */
void resume_device_irqs(void)
{
	struct irq_desc *desc;
	int irq;

	for_each_irq_desc(irq, desc) {
		unsigned long flags;

		if (!(desc->status & IRQ_SUSPENDED))
			continue;

		spin_lock_irqsave(&desc->lock, flags);
		__enable_irq(desc, irq, true);
		spin_unlock_irqrestore(&desc->lock, flags);
	}
}
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)
		if ((desc->status & IRQ_WAKEUP) && (desc->status & IRQ_PENDING))
			return -EBUSY;

	return 0;
}
Commit	Line	Data
0a0c5168 RW	1	/*
	2	* linux/kernel/irq/pm.c
	3	*
	4	* Copyright (C) 2009 Rafael J. Wysocki <[email protected]>, Novell Inc.
	5	*
	6	* This file contains power management functions related to interrupts.
	7	*/
	8
	9	#include <linux/irq.h>
	10	#include <linux/module.h>
	11	#include <linux/interrupt.h>
	12
	13	#include "internals.h"
	14
	15	/**
	16	* suspend_device_irqs - disable all currently enabled interrupt lines
	17	*
	18	* During system-wide suspend or hibernation device interrupts need to be
	19	* disabled at the chip level and this function is provided for this purpose.
	20	* It disables all interrupt lines that are enabled at the moment and sets the
	21	* IRQ_SUSPENDED flag for them.
	22	*/
	23	void suspend_device_irqs(void)
	24	{
	25	struct irq_desc *desc;
	26	int irq;
	27
	28	for_each_irq_desc(irq, desc) {
	29	unsigned long flags;
	30
	31	spin_lock_irqsave(&desc->lock, flags);
	32	__disable_irq(desc, irq, true);
	33	spin_unlock_irqrestore(&desc->lock, flags);
	34	}
	35
	36	for_each_irq_desc(irq, desc)
	37	if (desc->status & IRQ_SUSPENDED)
	38	synchronize_irq(irq);
	39	}
	40	EXPORT_SYMBOL_GPL(suspend_device_irqs);
	41
	42	/**
	43	* resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs()
	44	*
	45	* Enable all interrupt lines previously disabled by suspend_device_irqs() that
	46	* have the IRQ_SUSPENDED flag set.
	47	*/
	48	void resume_device_irqs(void)
	49	{
	50	struct irq_desc *desc;
	51	int irq;
	52
	53	for_each_irq_desc(irq, desc) {
	54	unsigned long flags;
	55
	56	if (!(desc->status & IRQ_SUSPENDED))
	57	continue;
	58
	59	spin_lock_irqsave(&desc->lock, flags);
	60	__enable_irq(desc, irq, true);
	61	spin_unlock_irqrestore(&desc->lock, flags);
	62	}
	63	}
	64	EXPORT_SYMBOL_GPL(resume_device_irqs);
65
66	/**
67	* check_wakeup_irqs - check if any wake-up interrupts are pending
68	*/
69	int check_wakeup_irqs(void)
70	{
71	struct irq_desc *desc;
72	int irq;
73
74	for_each_irq_desc(irq, desc)
75	if ((desc->status & IRQ_WAKEUP) && (desc->status & IRQ_PENDING))
76	return -EBUSY;
77
78	return 0;
79	}