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autoprobe.c
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autoprobe.c
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/*
* linux/kernel/irq/autoprobe.c
*
* Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
*
* This file contains the interrupt probing code and driver APIs.
*/
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/async.h>
#include "internals.h"
static DEFINE_MUTEX(probing_active);
unsigned long probe_irq_on(void)
{
struct irq_desc *desc;
unsigned long mask = 0;
int i;
async_synchronize_full();
mutex_lock(&probing_active);
for_each_irq_desc_reverse(i, desc) {
raw_spin_lock_irq(&desc->lock);
if (!desc->action && irq_settings_can_probe(desc)) {
if (desc->irq_data.chip->irq_set_type)
desc->irq_data.chip->irq_set_type(&desc->irq_data,
IRQ_TYPE_PROBE);
irq_startup(desc, false);
}
raw_spin_unlock_irq(&desc->lock);
}
msleep(20);
for_each_irq_desc_reverse(i, desc) {
raw_spin_lock_irq(&desc->lock);
if (!desc->action && irq_settings_can_probe(desc)) {
desc->istate |= IRQS_AUTODETECT | IRQS_WAITING;
if (irq_startup(desc, false))
desc->istate |= IRQS_PENDING;
}
raw_spin_unlock_irq(&desc->lock);
}
msleep(100);
for_each_irq_desc(i, desc) {
raw_spin_lock_irq(&desc->lock);
if (desc->istate & IRQS_AUTODETECT) {
if (!(desc->istate & IRQS_WAITING)) {
desc->istate &= ~IRQS_AUTODETECT;
irq_shutdown(desc);
} else
if (i < 32)
mask |= 1 << i;
}
raw_spin_unlock_irq(&desc->lock);
}
return mask;
}
EXPORT_SYMBOL(probe_irq_on);
unsigned int probe_irq_mask(unsigned long val)
{
unsigned int mask = 0;
struct irq_desc *desc;
int i;
for_each_irq_desc(i, desc) {
raw_spin_lock_irq(&desc->lock);
if (desc->istate & IRQS_AUTODETECT) {
if (i < 16 && !(desc->istate & IRQS_WAITING))
mask |= 1 << i;
desc->istate &= ~IRQS_AUTODETECT;
irq_shutdown(desc);
}
raw_spin_unlock_irq(&desc->lock);
}
mutex_unlock(&probing_active);
return mask & val;
}
EXPORT_SYMBOL(probe_irq_mask);
int probe_irq_off(unsigned long val)
{
int i, irq_found = 0, nr_of_irqs = 0;
struct irq_desc *desc;
for_each_irq_desc(i, desc) {
raw_spin_lock_irq(&desc->lock);
if (desc->istate & IRQS_AUTODETECT) {
if (!(desc->istate & IRQS_WAITING)) {
if (!nr_of_irqs)
irq_found = i;
nr_of_irqs++;
}
desc->istate &= ~IRQS_AUTODETECT;
irq_shutdown(desc);
}
raw_spin_unlock_irq(&desc->lock);
}
mutex_unlock(&probing_active);
if (nr_of_irqs > 1)
irq_found = -irq_found;
return irq_found;
}
EXPORT_SYMBOL(probe_irq_off);