projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 54f69b92 JK |
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 | ||
| a7b594b4 | 22 | static int irq = -1; |
| 54f69b92 JK |
23 | |
| 24 | static irqreturn_t dummy_interrupt(int irq, void *dev_id) | |
| 25 | { | |
| 26 | static int count = 0; | |
| 27 | ||
| 28 | if (count == 0) { | |
| 8b513d0c | 29 | printk(KERN_INFO "dummy-irq: interrupt occurred on IRQ %d\n", |
| 54f69b92 JK |
30 | irq); |
| 31 | count++; | |
| 32 | } | |
| 33 | ||
| 34 | return IRQ_NONE; | |
| 35 | } | |
| 36 | ||
| 37 | static int __init dummy_irq_init(void) | |
| 38 | { | |
| a7b594b4 JC |
39 | if (irq < 0) { |
| 40 | printk(KERN_ERR "dummy-irq: no IRQ given. Use irq=N\n"); | |
| 41 | return -EIO; | |
| 42 | } | |
| 54f69b92 JK |
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 | ||
| 51 | static void __exit dummy_irq_exit(void) | |
| 52 | { | |
| 53 | printk(KERN_INFO "dummy-irq unloaded\n"); | |
| 54 | free_irq(irq, &irq); | |
| 55 | } | |
| 56 | ||
| 57 | module_init(dummy_irq_init); | |
| 58 | module_exit(dummy_irq_exit); | |
| 59 | ||
| 60 | MODULE_LICENSE("GPL"); | |
| 61 | MODULE_AUTHOR("Jiri Kosina"); | |
| 62 | module_param(irq, uint, 0444); | |
| 63 | MODULE_PARM_DESC(irq, "The IRQ to register for"); |