chip.c

// SPDX-License-Identifier: GPL-2.0
/*
 * 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/core-api/genericirq.rst
 */

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

#include <trace/events/irq.h>

#include "internals.h"

static irqreturn_t bad_chained_irq(int irq, void *dev_id)
{
	WARN_ONCE(1, "Chained irq %d should not call an action\n", irq);
	return IRQ_NONE;
}

/*
 * Chained handlers should never call action on their IRQ. This default
 * action will emit warning if such thing happens.
 */
struct irqaction chained_action = {
	.handler = bad_chained_irq,
};

/**
 *	irq_set_chip - set the irq chip for an irq
 *	@irq:	irq number
 *	@chip:	pointer to irq chip description structure
 */
int irq_set_chip(unsigned int irq, struct irq_chip *chip)
{
	unsigned long flags;
	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);

	if (!desc)
		return -EINVAL;

	if (!chip)
		chip = &no_irq_chip;

	desc->irq_data.chip = chip;
	irq_put_desc_unlock(desc, flags);
	/*
	 * For !CONFIG_SPARSE_IRQ make the irq show up in
	 * allocated_irqs.
	 */
	irq_mark_irq(irq);
	return 0;
}
EXPORT_SYMBOL(irq_set_chip);

/**
 *	irq_set_type - set the irq trigger type for an irq
 *	@irq:	irq number
 *	@type:	IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
 */
int irq_set_irq_type(unsigned int irq, unsigned int type)
{
	unsigned long flags;