[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 <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;
}
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>
9bab0b7f	12	#include <linux/syscore_ops.h>
0a0c5168 RW	13
	14	#include "internals.h"
	15
	16	/**
	17	* suspend_device_irqs - disable all currently enabled interrupt lines
	18	*
c71320d0 RW	19	* During system-wide suspend or hibernation device drivers need to be prevented
	20	* from receiving interrupts and this function is provided for this purpose.
	21	* It marks all interrupt lines in use, except for the timer ones, as disabled
c531e836	22	* and sets the IRQS_SUSPENDED flag for each of them.
0a0c5168 RW	23	*/
	24	void suspend_device_irqs(void)
	25	{
	26	struct irq_desc *desc;
	27	int irq;
	28
	29	for_each_irq_desc(irq, desc) {
	30	unsigned long flags;
	31
239007b8	32	raw_spin_lock_irqsave(&desc->lock, flags);
0a0c5168	33	__disable_irq(desc, irq, true);
239007b8	34	raw_spin_unlock_irqrestore(&desc->lock, flags);
0a0c5168 RW	35	}
	36
	37	for_each_irq_desc(irq, desc)
c531e836	38	if (desc->istate & IRQS_SUSPENDED)
0a0c5168 RW	39	synchronize_irq(irq);
	40	}
	41	EXPORT_SYMBOL_GPL(suspend_device_irqs);
	42
9bab0b7f	43	static void resume_irqs(bool want_early)
0a0c5168 RW	44	{
	45	struct irq_desc *desc;
	46	int irq;
	47
	48	for_each_irq_desc(irq, desc) {
	49	unsigned long flags;
9bab0b7f IC	50	bool is_early = desc->action &&
	51	desc->action->flags & IRQF_EARLY_RESUME;
	52
	53	if (is_early != want_early)
	54	continue;
0a0c5168	55
239007b8	56	raw_spin_lock_irqsave(&desc->lock, flags);
0a0c5168	57	__enable_irq(desc, irq, true);
239007b8	58	raw_spin_unlock_irqrestore(&desc->lock, flags);
0a0c5168 RW	59	}
0a0c5168 RW	60	}
9bab0b7f IC	61
	62	/**
	63	* irq_pm_syscore_ops - enable interrupt lines early
	64	*
	65	* Enable all interrupt lines with %IRQF_EARLY_RESUME set.
	66	*/
	67	static void irq_pm_syscore_resume(void)
	68	{
	69	resume_irqs(true);
	70	}
	71
	72	static struct syscore_ops irq_pm_syscore_ops = {
	73	.resume = irq_pm_syscore_resume,
	74	};
	75
	76	static int __init irq_pm_init_ops(void)
	77	{
	78	register_syscore_ops(&irq_pm_syscore_ops);
	79	return 0;
	80	}
	81
	82	device_initcall(irq_pm_init_ops);
	83
	84	/**
	85	* resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs()
	86	*
	87	* Enable all non-%IRQF_EARLY_RESUME interrupt lines previously
	88	* disabled by suspend_device_irqs() that have the IRQS_SUSPENDED flag
	89	* set as well as those with %IRQF_FORCE_RESUME.
	90	*/
	91	void resume_device_irqs(void)
	92	{
	93	resume_irqs(false);
	94	}
0a0c5168 RW	95	EXPORT_SYMBOL_GPL(resume_device_irqs);
	96
	97	/**
	98	* check_wakeup_irqs - check if any wake-up interrupts are pending
	99	*/
	100	int check_wakeup_irqs(void)
	101	{
	102	struct irq_desc *desc;
	103	int irq;
	104
d209a699	105	for_each_irq_desc(irq, desc) {
9c6079aa TG	106	/*
	107	* Only interrupts which are marked as wakeup source
	108	* and have not been disabled before the suspend check
	109	* can abort suspend.
	110	*/
d209a699	111	if (irqd_is_wakeup_set(&desc->irq_data)) {
9c6079aa	112	if (desc->depth == 1 && desc->istate & IRQS_PENDING)
d209a699 TG	113	return -EBUSY;
	114	continue;
	115	}
	116	/*
	117	* Check the non wakeup interrupts whether they need
	118	* to be masked before finally going into suspend
	119	* state. That's for hardware which has no wakeup
	120	* source configuration facility. The chip
	121	* implementation indicates that with
	122	* IRQCHIP_MASK_ON_SUSPEND.
	123	*/
	124	if (desc->istate & IRQS_SUSPENDED &&
	125	irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND)
	126	mask_irq(desc);
	127	}
0a0c5168 RW	128
	129	return 0;
	130	}