[GitHub/mt8127/android_kernel_alcatel_ttab.git] / kernel / irq / pm.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 "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);

/**
 * resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs()
 *
 * Enable all interrupt lines previously disabled by suspend_device_irqs() that
 * have the IRQS_SUSPENDED flag set.
 */
void resume_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);
		__enable_irq(desc, irq, true);
		raw_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 (irqd_is_wakeup_set(&desc->irq_data)) {
			if (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 <rjw@sisk.pl>, 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	*
c71320d0 RW	18	* During system-wide suspend or hibernation device drivers need to be prevented
	19	* from receiving interrupts and this function is provided for this purpose.
	20	* It marks all interrupt lines in use, except for the timer ones, as disabled
c531e836	21	* and sets the IRQS_SUSPENDED flag for each of them.
0a0c5168 RW	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
239007b8	31	raw_spin_lock_irqsave(&desc->lock, flags);
0a0c5168	32	__disable_irq(desc, irq, true);
239007b8	33	raw_spin_unlock_irqrestore(&desc->lock, flags);
0a0c5168 RW	34	}
	35
	36	for_each_irq_desc(irq, desc)
c531e836	37	if (desc->istate & IRQS_SUSPENDED)
0a0c5168 RW	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
c531e836	46	* have the IRQS_SUSPENDED flag set.
0a0c5168 RW	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
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	}
	60	}
	61	EXPORT_SYMBOL_GPL(resume_device_irqs);
	62
	63	/**
	64	* check_wakeup_irqs - check if any wake-up interrupts are pending
	65	*/
	66	int check_wakeup_irqs(void)
	67	{
	68	struct irq_desc *desc;
	69	int irq;
	70
d209a699 TG	71	for_each_irq_desc(irq, desc) {
	72	if (irqd_is_wakeup_set(&desc->irq_data)) {
	73	if (desc->istate & IRQS_PENDING)
	74	return -EBUSY;
	75	continue;
	76	}
	77	/*
	78	* Check the non wakeup interrupts whether they need
	79	* to be masked before finally going into suspend
	80	* state. That's for hardware which has no wakeup
	81	* source configuration facility. The chip
	82	* implementation indicates that with
	83	* IRQCHIP_MASK_ON_SUSPEND.
	84	*/
	85	if (desc->istate & IRQS_SUSPENDED &&
	86	irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND)
	87	mask_irq(desc);
	88	}
0a0c5168 RW	89
	90	return 0;
	91	}