chip.c 20.4 KB
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/*
 * linux/kernel/irq/chip.c
 *
 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
 *
 * This file contains the core interrupt handling code, for irq-chip
 * based architectures.
 *
 * Detailed information is available in Documentation/DocBook/genericirq
 */

#include <linux/irq.h>
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#include <linux/msi.h>
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#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>

#include "internals.h"

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static void dynamic_irq_init_x(unsigned int irq, bool keep_chip_data)
22
{
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	struct irq_desc *desc;
24 25
	unsigned long flags;

26
	desc = irq_to_desc(irq);
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	if (!desc) {
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		WARN(1, KERN_ERR "Trying to initialize invalid IRQ%d\n", irq);
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		return;
	}

	/* Ensure we don't have left over values from a previous use of this irq */
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	raw_spin_lock_irqsave(&desc->lock, flags);
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	desc->status = IRQ_DISABLED;
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	desc->irq_data.chip = &no_irq_chip;
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	desc->handle_irq = handle_bad_irq;
	desc->depth = 1;
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	desc->irq_data.msi_desc = NULL;
	desc->irq_data.handler_data = NULL;
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	if (!keep_chip_data)
41
		desc->irq_data.chip_data = NULL;
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	desc->action = NULL;
	desc->irq_count = 0;
	desc->irqs_unhandled = 0;
#ifdef CONFIG_SMP
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	cpumask_setall(desc->irq_data.affinity);
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#ifdef CONFIG_GENERIC_PENDING_IRQ
	cpumask_clear(desc->pending_mask);
#endif
50
#endif
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	raw_spin_unlock_irqrestore(&desc->lock, flags);
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}

/**
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 *	dynamic_irq_init - initialize a dynamically allocated irq
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 *	@irq:	irq number to initialize
 */
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void dynamic_irq_init(unsigned int irq)
{
	dynamic_irq_init_x(irq, false);
}

/**
 *	dynamic_irq_init_keep_chip_data - initialize a dynamically allocated irq
 *	@irq:	irq number to initialize
 *
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 *	does not set irq_to_desc(irq)->irq_data.chip_data to NULL
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 */
void dynamic_irq_init_keep_chip_data(unsigned int irq)
{
	dynamic_irq_init_x(irq, true);
}

static void dynamic_irq_cleanup_x(unsigned int irq, bool keep_chip_data)
75
{
76
	struct irq_desc *desc = irq_to_desc(irq);
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	unsigned long flags;

79
	if (!desc) {
80
		WARN(1, KERN_ERR "Trying to cleanup invalid IRQ%d\n", irq);
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		return;
	}

84
	raw_spin_lock_irqsave(&desc->lock, flags);
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	if (desc->action) {
86
		raw_spin_unlock_irqrestore(&desc->lock, flags);
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		WARN(1, KERN_ERR "Destroying IRQ%d without calling free_irq\n",
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			irq);
		return;
	}
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	desc->irq_data.msi_desc = NULL;
	desc->irq_data.handler_data = NULL;
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	if (!keep_chip_data)
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		desc->irq_data.chip_data = NULL;
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	desc->handle_irq = handle_bad_irq;
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	desc->irq_data.chip = &no_irq_chip;
97
	desc->name = NULL;
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	clear_kstat_irqs(desc);
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	raw_spin_unlock_irqrestore(&desc->lock, flags);
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}

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/**
 *	dynamic_irq_cleanup - cleanup a dynamically allocated irq
 *	@irq:	irq number to initialize
 */
void dynamic_irq_cleanup(unsigned int irq)
{
	dynamic_irq_cleanup_x(irq, false);
}

/**
 *	dynamic_irq_cleanup_keep_chip_data - cleanup a dynamically allocated irq
 *	@irq:	irq number to initialize
 *
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 *	does not set irq_to_desc(irq)->irq_data.chip_data to NULL
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 */
void dynamic_irq_cleanup_keep_chip_data(unsigned int irq)
{
	dynamic_irq_cleanup_x(irq, true);
}

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/**
 *	set_irq_chip - set the irq chip for an irq
 *	@irq:	irq number
 *	@chip:	pointer to irq chip description structure
 */
int set_irq_chip(unsigned int irq, struct irq_chip *chip)
{
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	struct irq_desc *desc = irq_to_desc(irq);
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	unsigned long flags;

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	if (!desc) {
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		WARN(1, KERN_ERR "Trying to install chip for IRQ%d\n", irq);
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		return -EINVAL;
	}

	if (!chip)
		chip = &no_irq_chip;

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	raw_spin_lock_irqsave(&desc->lock, flags);
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	irq_chip_set_defaults(chip);
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	desc->irq_data.chip = chip;
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	raw_spin_unlock_irqrestore(&desc->lock, flags);
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	return 0;
}
EXPORT_SYMBOL(set_irq_chip);

/**
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 *	set_irq_type - set the irq trigger type for an irq
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 *	@irq:	irq number
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 *	@type:	IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
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 */
int set_irq_type(unsigned int irq, unsigned int type)
{
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	struct irq_desc *desc = irq_to_desc(irq);
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	unsigned long flags;
	int ret = -ENXIO;

161
	if (!desc) {
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		printk(KERN_ERR "Trying to set irq type for IRQ%d\n", irq);
		return -ENODEV;
	}

166
	type &= IRQ_TYPE_SENSE_MASK;
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	if (type == IRQ_TYPE_NONE)
		return 0;

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	raw_spin_lock_irqsave(&desc->lock, flags);
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	ret = __irq_set_trigger(desc, irq, type);
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	raw_spin_unlock_irqrestore(&desc->lock, flags);
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	return ret;
}
EXPORT_SYMBOL(set_irq_type);

/**
 *	set_irq_data - set irq type data for an irq
 *	@irq:	Interrupt number
 *	@data:	Pointer to interrupt specific data
 *
 *	Set the hardware irq controller data for an irq
 */
int set_irq_data(unsigned int irq, void *data)
{
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	struct irq_desc *desc = irq_to_desc(irq);
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	unsigned long flags;

189
	if (!desc) {
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		printk(KERN_ERR
		       "Trying to install controller data for IRQ%d\n", irq);
		return -EINVAL;
	}

195
	raw_spin_lock_irqsave(&desc->lock, flags);
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	desc->irq_data.handler_data = data;
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	raw_spin_unlock_irqrestore(&desc->lock, flags);
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	return 0;
}
EXPORT_SYMBOL(set_irq_data);

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/**
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 *	set_irq_msi - set MSI descriptor data for an irq
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 *	@irq:	Interrupt number
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 *	@entry:	Pointer to MSI descriptor data
206
 *
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 *	Set the MSI descriptor entry for an irq
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 */
int set_irq_msi(unsigned int irq, struct msi_desc *entry)
{
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	struct irq_desc *desc = irq_to_desc(irq);
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	unsigned long flags;

214
	if (!desc) {
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		printk(KERN_ERR
		       "Trying to install msi data for IRQ%d\n", irq);
		return -EINVAL;
	}
219

220
	raw_spin_lock_irqsave(&desc->lock, flags);
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	desc->irq_data.msi_desc = entry;
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	if (entry)
		entry->irq = irq;
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	raw_spin_unlock_irqrestore(&desc->lock, flags);
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	return 0;
}

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/**
 *	set_irq_chip_data - set irq chip data for an irq
 *	@irq:	Interrupt number
 *	@data:	Pointer to chip specific data
 *
 *	Set the hardware irq chip data for an irq
 */
int set_irq_chip_data(unsigned int irq, void *data)
{
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	struct irq_desc *desc = irq_to_desc(irq);
238 239
	unsigned long flags;

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	if (!desc) {
		printk(KERN_ERR
		       "Trying to install chip data for IRQ%d\n", irq);
		return -EINVAL;
	}

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	if (!desc->irq_data.chip) {
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		printk(KERN_ERR "BUG: bad set_irq_chip_data(IRQ#%d)\n", irq);
		return -EINVAL;
	}

251
	raw_spin_lock_irqsave(&desc->lock, flags);
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	desc->irq_data.chip_data = data;
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	raw_spin_unlock_irqrestore(&desc->lock, flags);
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	return 0;
}
EXPORT_SYMBOL(set_irq_chip_data);

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/**
 *	set_irq_nested_thread - Set/Reset the IRQ_NESTED_THREAD flag of an irq
 *
 *	@irq:	Interrupt number
 *	@nest:	0 to clear / 1 to set the IRQ_NESTED_THREAD flag
 *
 *	The IRQ_NESTED_THREAD flag indicates that on
 *	request_threaded_irq() no separate interrupt thread should be
 *	created for the irq as the handler are called nested in the
 *	context of a demultiplexing interrupt handler thread.
 */
void set_irq_nested_thread(unsigned int irq, int nest)
{
	struct irq_desc *desc = irq_to_desc(irq);
	unsigned long flags;

	if (!desc)
		return;

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	raw_spin_lock_irqsave(&desc->lock, flags);
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	if (nest)
		desc->status |= IRQ_NESTED_THREAD;
	else
		desc->status &= ~IRQ_NESTED_THREAD;
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	raw_spin_unlock_irqrestore(&desc->lock, flags);
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}
EXPORT_SYMBOL_GPL(set_irq_nested_thread);

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/*
 * default enable function
 */
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static void default_enable(struct irq_data *data)
291
{
292
	struct irq_desc *desc = irq_data_to_desc(data);
293

294
	desc->irq_data.chip->irq_unmask(&desc->irq_data);
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	desc->status &= ~IRQ_MASKED;
}

/*
 * default disable function
 */
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static void default_disable(struct irq_data *data)
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{
}

/*
 * default startup function
 */
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static unsigned int default_startup(struct irq_data *data)
309
{
310
	struct irq_desc *desc = irq_data_to_desc(data);
311

312
	desc->irq_data.chip->irq_enable(data);
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	return 0;
}

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/*
 * default shutdown function
 */
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static void default_shutdown(struct irq_data *data)
320
{
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	struct irq_desc *desc = irq_data_to_desc(data);
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323
	desc->irq_data.chip->irq_mask(&desc->irq_data);
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	desc->status |= IRQ_MASKED;
}

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/* Temporary migration helpers */
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static void compat_irq_mask(struct irq_data *data)
{
	data->chip->mask(data->irq);
}

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static void compat_irq_unmask(struct irq_data *data)
{
	data->chip->unmask(data->irq);
}

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static void compat_irq_ack(struct irq_data *data)
{
	data->chip->ack(data->irq);
}

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static void compat_irq_mask_ack(struct irq_data *data)
{
	data->chip->mask_ack(data->irq);
}

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static void compat_irq_eoi(struct irq_data *data)
{
	data->chip->eoi(data->irq);
}

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static void compat_irq_enable(struct irq_data *data)
{
	data->chip->enable(data->irq);
}

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static void compat_irq_disable(struct irq_data *data)
{
	data->chip->disable(data->irq);
}

static void compat_irq_shutdown(struct irq_data *data)
{
	data->chip->shutdown(data->irq);
}

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static unsigned int compat_irq_startup(struct irq_data *data)
{
	return data->chip->startup(data->irq);
}

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static void compat_bus_lock(struct irq_data *data)
{
	data->chip->bus_lock(data->irq);
}

static void compat_bus_sync_unlock(struct irq_data *data)
{
	data->chip->bus_sync_unlock(data->irq);
}

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/*
 * Fixup enable/disable function pointers
 */
void irq_chip_set_defaults(struct irq_chip *chip)
{
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	/*
	 * Compat fixup functions need to be before we set the
	 * defaults for enable/disable/startup/shutdown
	 */
	if (chip->enable)
		chip->irq_enable = compat_irq_enable;
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	if (chip->disable)
		chip->irq_disable = compat_irq_disable;
	if (chip->shutdown)
		chip->irq_shutdown = compat_irq_shutdown;
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	if (chip->startup)
		chip->irq_startup = compat_irq_startup;
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	/*
	 * The real defaults
	 */
	if (!chip->irq_enable)
		chip->irq_enable = default_enable;
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	if (!chip->irq_disable)
		chip->irq_disable = default_disable;
408 409
	if (!chip->irq_startup)
		chip->irq_startup = default_startup;
410
	/*
411 412
	 * We use chip->irq_disable, when the user provided its own. When
	 * we have default_disable set for chip->irq_disable, then we need
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	 * to use default_shutdown, otherwise the irq line is not
	 * disabled on free_irq():
	 */
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	if (!chip->irq_shutdown)
		chip->irq_shutdown = chip->irq_disable != default_disable ?
			chip->irq_disable : default_shutdown;
419 420
	if (!chip->end)
		chip->end = dummy_irq_chip.end;
421

422 423 424
	/*
	 * Now fix up the remaining compat handlers
	 */
425 426 427 428
	if (chip->bus_lock)
		chip->irq_bus_lock = compat_bus_lock;
	if (chip->bus_sync_unlock)
		chip->irq_bus_sync_unlock = compat_bus_sync_unlock;
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	if (chip->mask)
		chip->irq_mask = compat_irq_mask;
431 432
	if (chip->unmask)
		chip->irq_unmask = compat_irq_unmask;
433 434
	if (chip->ack)
		chip->irq_ack = compat_irq_ack;
435 436
	if (chip->mask_ack)
		chip->irq_mask_ack = compat_irq_mask_ack;
437 438
	if (chip->eoi)
		chip->irq_eoi = compat_irq_eoi;
439 440
}

441
static inline void mask_ack_irq(struct irq_desc *desc)
442
{
443 444
	if (desc->irq_data.chip->irq_mask_ack)
		desc->irq_data.chip->irq_mask_ack(&desc->irq_data);
445
	else {
446
		desc->irq_data.chip->irq_mask(&desc->irq_data);
447 448
		if (desc->irq_data.chip->irq_ack)
			desc->irq_data.chip->irq_ack(&desc->irq_data);
449
	}
450 451 452
	desc->status |= IRQ_MASKED;
}

453
static inline void mask_irq(struct irq_desc *desc)
454
{
455 456
	if (desc->irq_data.chip->irq_mask) {
		desc->irq_data.chip->irq_mask(&desc->irq_data);
457 458 459 460
		desc->status |= IRQ_MASKED;
	}
}

461
static inline void unmask_irq(struct irq_desc *desc)
462
{
463 464
	if (desc->irq_data.chip->irq_unmask) {
		desc->irq_data.chip->irq_unmask(&desc->irq_data);
465 466
		desc->status &= ~IRQ_MASKED;
	}
467 468
}

469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484
/*
 *	handle_nested_irq - Handle a nested irq from a irq thread
 *	@irq:	the interrupt number
 *
 *	Handle interrupts which are nested into a threaded interrupt
 *	handler. The handler function is called inside the calling
 *	threads context.
 */
void handle_nested_irq(unsigned int irq)
{
	struct irq_desc *desc = irq_to_desc(irq);
	struct irqaction *action;
	irqreturn_t action_ret;

	might_sleep();

485
	raw_spin_lock_irq(&desc->lock);
486 487 488 489 490 491 492 493

	kstat_incr_irqs_this_cpu(irq, desc);

	action = desc->action;
	if (unlikely(!action || (desc->status & IRQ_DISABLED)))
		goto out_unlock;

	desc->status |= IRQ_INPROGRESS;
494
	raw_spin_unlock_irq(&desc->lock);
495 496 497 498 499

	action_ret = action->thread_fn(action->irq, action->dev_id);
	if (!noirqdebug)
		note_interrupt(irq, desc, action_ret);

500
	raw_spin_lock_irq(&desc->lock);
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	desc->status &= ~IRQ_INPROGRESS;

out_unlock:
504
	raw_spin_unlock_irq(&desc->lock);
505 506 507
}
EXPORT_SYMBOL_GPL(handle_nested_irq);

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/**
 *	handle_simple_irq - Simple and software-decoded IRQs.
 *	@irq:	the interrupt number
 *	@desc:	the interrupt description structure for this irq
 *
 *	Simple interrupts are either sent from a demultiplexing interrupt
 *	handler or come from hardware, where no interrupt hardware control
 *	is necessary.
 *
 *	Note: The caller is expected to handle the ack, clear, mask and
 *	unmask issues if necessary.
 */
520
void
521
handle_simple_irq(unsigned int irq, struct irq_desc *desc)
522 523 524 525
{
	struct irqaction *action;
	irqreturn_t action_ret;

526
	raw_spin_lock(&desc->lock);
527 528 529

	if (unlikely(desc->status & IRQ_INPROGRESS))
		goto out_unlock;
530
	desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
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531
	kstat_incr_irqs_this_cpu(irq, desc);
532 533

	action = desc->action;
534
	if (unlikely(!action || (desc->status & IRQ_DISABLED)))
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		goto out_unlock;

	desc->status |= IRQ_INPROGRESS;
538
	raw_spin_unlock(&desc->lock);
539

540
	action_ret = handle_IRQ_event(irq, action);
541
	if (!noirqdebug)
542
		note_interrupt(irq, desc, action_ret);
543

544
	raw_spin_lock(&desc->lock);
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	desc->status &= ~IRQ_INPROGRESS;
out_unlock:
547
	raw_spin_unlock(&desc->lock);
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}

/**
 *	handle_level_irq - Level type irq handler
 *	@irq:	the interrupt number
 *	@desc:	the interrupt description structure for this irq
 *
 *	Level type interrupts are active as long as the hardware line has
 *	the active level. This may require to mask the interrupt and unmask
 *	it after the associated handler has acknowledged the device, so the
 *	interrupt line is back to inactive.
 */
560
void
561
handle_level_irq(unsigned int irq, struct irq_desc *desc)
562 563 564 565
{
	struct irqaction *action;
	irqreturn_t action_ret;

566
	raw_spin_lock(&desc->lock);
567
	mask_ack_irq(desc);
568 569

	if (unlikely(desc->status & IRQ_INPROGRESS))
570
		goto out_unlock;
571
	desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
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	kstat_incr_irqs_this_cpu(irq, desc);
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	/*
	 * If its disabled or no action available
	 * keep it masked and get out of here
	 */
	action = desc->action;
579
	if (unlikely(!action || (desc->status & IRQ_DISABLED)))
580
		goto out_unlock;
581 582

	desc->status |= IRQ_INPROGRESS;
583
	raw_spin_unlock(&desc->lock);
584

585
	action_ret = handle_IRQ_event(irq, action);
586
	if (!noirqdebug)
587
		note_interrupt(irq, desc, action_ret);
588

589
	raw_spin_lock(&desc->lock);
590
	desc->status &= ~IRQ_INPROGRESS;
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591

592
	if (!(desc->status & (IRQ_DISABLED | IRQ_ONESHOT)))
593
		unmask_irq(desc);
594
out_unlock:
595
	raw_spin_unlock(&desc->lock);
596
}
597
EXPORT_SYMBOL_GPL(handle_level_irq);
598 599

/**
600
 *	handle_fasteoi_irq - irq handler for transparent controllers
601 602 603
 *	@irq:	the interrupt number
 *	@desc:	the interrupt description structure for this irq
 *
604
 *	Only a single callback will be issued to the chip: an ->eoi()
605 606 607 608
 *	call when the interrupt has been serviced. This enables support
 *	for modern forms of interrupt handlers, which handle the flow
 *	details in hardware, transparently.
 */
609
void
610
handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
611 612 613 614
{
	struct irqaction *action;
	irqreturn_t action_ret;

615
	raw_spin_lock(&desc->lock);
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	if (unlikely(desc->status & IRQ_INPROGRESS))
		goto out;

	desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
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621
	kstat_incr_irqs_this_cpu(irq, desc);
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	/*
	 * If its disabled or no action available
625
	 * then mask it and get out of here:
626 627
	 */
	action = desc->action;
628 629
	if (unlikely(!action || (desc->status & IRQ_DISABLED))) {
		desc->status |= IRQ_PENDING;
630
		mask_irq(desc);
631
		goto out;
632
	}
633 634

	desc->status |= IRQ_INPROGRESS;
635
	desc->status &= ~IRQ_PENDING;
636
	raw_spin_unlock(&desc->lock);
637

638
	action_ret = handle_IRQ_event(irq, action);
639
	if (!noirqdebug)
640
		note_interrupt(irq, desc, action_ret);
641

642
	raw_spin_lock(&desc->lock);
643 644
	desc->status &= ~IRQ_INPROGRESS;
out:
645
	desc->irq_data.chip->irq_eoi(&desc->irq_data);
646

647
	raw_spin_unlock(&desc->lock);
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}

/**
 *	handle_edge_irq - edge type IRQ handler
 *	@irq:	the interrupt number
 *	@desc:	the interrupt description structure for this irq
 *
 *	Interrupt occures on the falling and/or rising edge of a hardware
 *	signal. The occurence is latched into the irq controller hardware
 *	and must be acked in order to be reenabled. After the ack another
 *	interrupt can happen on the same source even before the first one
659
 *	is handled by the associated event handler. If this happens it
660 661 662 663 664 665
 *	might be necessary to disable (mask) the interrupt depending on the
 *	controller hardware. This requires to reenable the interrupt inside
 *	of the loop which handles the interrupts which have arrived while
 *	the handler was running. If all pending interrupts are handled, the
 *	loop is left.
 */
666
void
667
handle_edge_irq(unsigned int irq, struct irq_desc *desc)
668
{
669
	raw_spin_lock(&desc->lock);
670 671 672 673 674 675 676 677 678 679 680

	desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);

	/*
	 * If we're currently running this IRQ, or its disabled,
	 * we shouldn't process the IRQ. Mark it pending, handle
	 * the necessary masking and go out
	 */
	if (unlikely((desc->status & (IRQ_INPROGRESS | IRQ_DISABLED)) ||
		    !desc->action)) {
		desc->status |= (IRQ_PENDING | IRQ_MASKED);
681
		mask_ack_irq(desc);
682 683
		goto out_unlock;
	}
T
Thomas Gleixner 已提交
684
	kstat_incr_irqs_this_cpu(irq, desc);
685 686

	/* Start handling the irq */
687
	desc->irq_data.chip->irq_ack(&desc->irq_data);
688 689 690 691 692 693 694 695 696

	/* Mark the IRQ currently in progress.*/
	desc->status |= IRQ_INPROGRESS;

	do {
		struct irqaction *action = desc->action;
		irqreturn_t action_ret;

		if (unlikely(!action)) {
697
			mask_irq(desc);
698 699 700 701 702 703 704 705 706 707 708
			goto out_unlock;
		}

		/*
		 * When another irq arrived while we were handling
		 * one, we could have masked the irq.
		 * Renable it, if it was not disabled in meantime.
		 */
		if (unlikely((desc->status &
			       (IRQ_PENDING | IRQ_MASKED | IRQ_DISABLED)) ==
			      (IRQ_PENDING | IRQ_MASKED))) {
709
			unmask_irq(desc);
710 711 712
		}

		desc->status &= ~IRQ_PENDING;
713
		raw_spin_unlock(&desc->lock);
714
		action_ret = handle_IRQ_event(irq, action);
715
		if (!noirqdebug)
716
			note_interrupt(irq, desc, action_ret);
717
		raw_spin_lock(&desc->lock);
718 719 720 721 722

	} while ((desc->status & (IRQ_PENDING | IRQ_DISABLED)) == IRQ_PENDING);

	desc->status &= ~IRQ_INPROGRESS;
out_unlock:
723
	raw_spin_unlock(&desc->lock);
724 725 726
}

/**
L
Liuweni 已提交
727
 *	handle_percpu_irq - Per CPU local irq handler
728 729 730 731 732
 *	@irq:	the interrupt number
 *	@desc:	the interrupt description structure for this irq
 *
 *	Per CPU interrupts on SMP machines without locking requirements
 */
733
void
734
handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
735 736 737
{
	irqreturn_t action_ret;

T
Thomas Gleixner 已提交
738
	kstat_incr_irqs_this_cpu(irq, desc);
739

740 741
	if (desc->irq_data.chip->irq_ack)
		desc->irq_data.chip->irq_ack(&desc->irq_data);
742

743
	action_ret = handle_IRQ_event(irq, desc->action);
744
	if (!noirqdebug)
745
		note_interrupt(irq, desc, action_ret);
746

747 748
	if (desc->irq_data.chip->irq_eoi)
		desc->irq_data.chip->irq_eoi(&desc->irq_data);
749 750 751
}

void
752 753
__set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
		  const char *name)
754
{
755
	struct irq_desc *desc = irq_to_desc(irq);
756 757
	unsigned long flags;

758
	if (!desc) {
759 760 761 762 763 764 765
		printk(KERN_ERR
		       "Trying to install type control for IRQ%d\n", irq);
		return;
	}

	if (!handle)
		handle = handle_bad_irq;
766
	else if (desc->irq_data.chip == &no_irq_chip) {
767
		printk(KERN_WARNING "Trying to install %sinterrupt handler "
768
		       "for IRQ%d\n", is_chained ? "chained " : "", irq);
769 770 771 772 773 774 775
		/*
		 * Some ARM implementations install a handler for really dumb
		 * interrupt hardware without setting an irq_chip. This worked
		 * with the ARM no_irq_chip but the check in setup_irq would
		 * prevent us to setup the interrupt at all. Switch it to
		 * dummy_irq_chip for easy transition.
		 */
776
		desc->irq_data.chip = &dummy_irq_chip;
777
	}
778

779
	chip_bus_lock(desc);
780
	raw_spin_lock_irqsave(&desc->lock, flags);
781 782 783

	/* Uninstall? */
	if (handle == handle_bad_irq) {
784
		if (desc->irq_data.chip != &no_irq_chip)
785
			mask_ack_irq(desc);
786 787 788 789
		desc->status |= IRQ_DISABLED;
		desc->depth = 1;
	}
	desc->handle_irq = handle;
790
	desc->name = name;
791 792 793 794 795

	if (handle != handle_bad_irq && is_chained) {
		desc->status &= ~IRQ_DISABLED;
		desc->status |= IRQ_NOREQUEST | IRQ_NOPROBE;
		desc->depth = 0;
796
		desc->irq_data.chip->irq_startup(&desc->irq_data);
797
	}
798
	raw_spin_unlock_irqrestore(&desc->lock, flags);
799
	chip_bus_sync_unlock(desc);
800
}
801
EXPORT_SYMBOL_GPL(__set_irq_handler);
802 803 804

void
set_irq_chip_and_handler(unsigned int irq, struct irq_chip *chip,
805
			 irq_flow_handler_t handle)
806 807
{
	set_irq_chip(irq, chip);
808
	__set_irq_handler(irq, handle, 0, NULL);
809 810
}

811 812 813
void
set_irq_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
			      irq_flow_handler_t handle, const char *name)
814
{
815 816
	set_irq_chip(irq, chip);
	__set_irq_handler(irq, handle, 0, name);
817
}
R
Ralf Baechle 已提交
818

819
void set_irq_noprobe(unsigned int irq)
R
Ralf Baechle 已提交
820
{
821
	struct irq_desc *desc = irq_to_desc(irq);
R
Ralf Baechle 已提交
822 823
	unsigned long flags;

824
	if (!desc) {
R
Ralf Baechle 已提交
825 826 827 828
		printk(KERN_ERR "Trying to mark IRQ%d non-probeable\n", irq);
		return;
	}

829
	raw_spin_lock_irqsave(&desc->lock, flags);
R
Ralf Baechle 已提交
830
	desc->status |= IRQ_NOPROBE;
831
	raw_spin_unlock_irqrestore(&desc->lock, flags);
R
Ralf Baechle 已提交
832 833
}

834
void set_irq_probe(unsigned int irq)
R
Ralf Baechle 已提交
835
{
836
	struct irq_desc *desc = irq_to_desc(irq);
R
Ralf Baechle 已提交
837 838
	unsigned long flags;

839
	if (!desc) {
R
Ralf Baechle 已提交
840 841 842 843
		printk(KERN_ERR "Trying to mark IRQ%d probeable\n", irq);
		return;
	}

844
	raw_spin_lock_irqsave(&desc->lock, flags);
R
Ralf Baechle 已提交
845
	desc->status &= ~IRQ_NOPROBE;
846
	raw_spin_unlock_irqrestore(&desc->lock, flags);
R
Ralf Baechle 已提交
847
}