1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * Dummy IRQ handler driver.
 4 *
 5 * This module only registers itself as a handler that is specified to it
 6 * by the 'irq' parameter.
 7 *
 8 * The sole purpose of this module is to help with debugging of systems on
 9 * which spurious IRQs would happen on disabled IRQ vector.
10 *
11 * Copyright (C) 2013 Jiri Kosina
12 */
13
 
 
 
 
 
14#include <linux/module.h>
15#include <linux/irq.h>
16#include <linux/interrupt.h>
17
18static int irq = -1;
19
20static irqreturn_t dummy_interrupt(int irq, void *dev_id)
21{
22	static int count = 0;
23
24	if (count == 0) {
25		printk(KERN_INFO "dummy-irq: interrupt occurred on IRQ %d\n",
26				irq);
27		count++;
28	}
29
30	return IRQ_NONE;
31}
32
33static int __init dummy_irq_init(void)
34{
35	if (irq < 0) {
36		printk(KERN_ERR "dummy-irq: no IRQ given.  Use irq=N\n");
37		return -EIO;
38	}
39	if (request_irq(irq, &dummy_interrupt, IRQF_SHARED, "dummy_irq", &irq)) {
40		printk(KERN_ERR "dummy-irq: cannot register IRQ %d\n", irq);
41		return -EIO;
42	}
43	printk(KERN_INFO "dummy-irq: registered for IRQ %d\n", irq);
44	return 0;
45}
46
47static void __exit dummy_irq_exit(void)
48{
49	printk(KERN_INFO "dummy-irq unloaded\n");
50	free_irq(irq, &irq);
51}
52
53module_init(dummy_irq_init);
54module_exit(dummy_irq_exit);
55
56MODULE_LICENSE("GPL");
57MODULE_AUTHOR("Jiri Kosina");
58module_param_hw(irq, uint, irq, 0444);
59MODULE_PARM_DESC(irq, "The IRQ to register for");
60MODULE_DESCRIPTION("Dummy IRQ handler driver");

 
 1/*
 2 * Dummy IRQ handler driver.
 3 *
 4 * This module only registers itself as a handler that is specified to it
 5 * by the 'irq' parameter.
 6 *
 7 * The sole purpose of this module is to help with debugging of systems on
 8 * which spurious IRQs would happen on disabled IRQ vector.
 9 *
10 * Copyright (C) 2013 Jiri Kosina
11 */
12
13/*
14 * This program is free software; you can redistribute it and/or modify it
15 * under the terms of the GNU General Public License version 2 as published by
16 * the Free Software Foundation.
17 */
18#include <linux/module.h>
19#include <linux/irq.h>
20#include <linux/interrupt.h>
21
22static int irq = -1;
23
24static irqreturn_t dummy_interrupt(int irq, void *dev_id)
25{
26	static int count = 0;
27
28	if (count == 0) {
29		printk(KERN_INFO "dummy-irq: interrupt occurred on IRQ %d\n",
30				irq);
31		count++;
32	}
33
34	return IRQ_NONE;
35}
36
37static int __init dummy_irq_init(void)
38{
39	if (irq < 0) {
40		printk(KERN_ERR "dummy-irq: no IRQ given.  Use irq=N\n");
41		return -EIO;
42	}
43	if (request_irq(irq, &dummy_interrupt, IRQF_SHARED, "dummy_irq", &irq)) {
44		printk(KERN_ERR "dummy-irq: cannot register IRQ %d\n", irq);
45		return -EIO;
46	}
47	printk(KERN_INFO "dummy-irq: registered for IRQ %d\n", irq);
48	return 0;
49}
50
51static void __exit dummy_irq_exit(void)
52{
53	printk(KERN_INFO "dummy-irq unloaded\n");
54	free_irq(irq, &irq);
55}
56
57module_init(dummy_irq_init);
58module_exit(dummy_irq_exit);
59
60MODULE_LICENSE("GPL");
61MODULE_AUTHOR("Jiri Kosina");
62module_param_hw(irq, uint, irq, 0444);
63MODULE_PARM_DESC(irq, "The IRQ to register for");
64MODULE_DESCRIPTION("Dummy IRQ handler driver");