1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
4 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
5 *
6 * This file contains the dummy interrupt chip implementation
7 */
8#include <linux/interrupt.h>
9#include <linux/irq.h>
10#include <linux/export.h>
11
12#include "internals.h"
13
14/*
15 * What should we do if we get a hw irq event on an illegal vector?
16 * Each architecture has to answer this themselves.
17 */
18static void ack_bad(struct irq_data *data)
19{
20 struct irq_desc *desc = irq_data_to_desc(data);
21
22 print_irq_desc(irq: data->irq, desc);
23 ack_bad_irq(irq: data->irq);
24}
25
26/*
27 * NOP functions
28 */
29static void noop(struct irq_data *data) { }
30
31static unsigned int noop_ret(struct irq_data *data)
32{
33 return 0;
34}
35
36/*
37 * Generic no controller implementation
38 */
39struct irq_chip no_irq_chip = {
40 .name = "none",
41 .irq_startup = noop_ret,
42 .irq_shutdown = noop,
43 .irq_enable = noop,
44 .irq_disable = noop,
45 .irq_ack = ack_bad,
46 .flags = IRQCHIP_SKIP_SET_WAKE,
47};
48
49/*
50 * Generic dummy implementation which can be used for
51 * real dumb interrupt sources
52 */
53struct irq_chip dummy_irq_chip = {
54 .name = "dummy",
55 .irq_startup = noop_ret,
56 .irq_shutdown = noop,
57 .irq_enable = noop,
58 .irq_disable = noop,
59 .irq_ack = noop,
60 .irq_mask = noop,
61 .irq_unmask = noop,
62 .flags = IRQCHIP_SKIP_SET_WAKE,
63};
64EXPORT_SYMBOL_GPL(dummy_irq_chip);
65

source code of linux/kernel/irq/dummychip.c