Blame view

drivers/misc/dummy-irq.c 1.36 KB
d2912cb15   Thomas Gleixner   treewide: Replace...
1
  // SPDX-License-Identifier: GPL-2.0-only
54f69b92f   Jiri Kosina   dummy-irq: introd...
2
3
4
5
6
7
8
9
10
11
12
  /*
   * Dummy IRQ handler driver.
   *
   * This module only registers itself as a handler that is specified to it
   * by the 'irq' parameter.
   *
   * The sole purpose of this module is to help with debugging of systems on
   * which spurious IRQs would happen on disabled IRQ vector.
   *
   * Copyright (C) 2013 Jiri Kosina
   */
54f69b92f   Jiri Kosina   dummy-irq: introd...
13
14
15
  #include <linux/module.h>
  #include <linux/irq.h>
  #include <linux/interrupt.h>
a7b594b49   Jonathan Corbet   dummy-irq: requir...
16
  static int irq = -1;
54f69b92f   Jiri Kosina   dummy-irq: introd...
17
18
19
20
21
22
  
  static irqreturn_t dummy_interrupt(int irq, void *dev_id)
  {
  	static int count = 0;
  
  	if (count == 0) {
8b513d0cf   Masanari Iida   treewide: Fix typ...
23
24
  		printk(KERN_INFO "dummy-irq: interrupt occurred on IRQ %d
  ",
54f69b92f   Jiri Kosina   dummy-irq: introd...
25
26
27
28
29
30
31
32
33
  				irq);
  		count++;
  	}
  
  	return IRQ_NONE;
  }
  
  static int __init dummy_irq_init(void)
  {
a7b594b49   Jonathan Corbet   dummy-irq: requir...
34
35
36
37
38
  	if (irq < 0) {
  		printk(KERN_ERR "dummy-irq: no IRQ given.  Use irq=N
  ");
  		return -EIO;
  	}
54f69b92f   Jiri Kosina   dummy-irq: introd...
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
  	if (request_irq(irq, &dummy_interrupt, IRQF_SHARED, "dummy_irq", &irq)) {
  		printk(KERN_ERR "dummy-irq: cannot register IRQ %d
  ", irq);
  		return -EIO;
  	}
  	printk(KERN_INFO "dummy-irq: registered for IRQ %d
  ", irq);
  	return 0;
  }
  
  static void __exit dummy_irq_exit(void)
  {
  	printk(KERN_INFO "dummy-irq unloaded
  ");
  	free_irq(irq, &irq);
  }
  
  module_init(dummy_irq_init);
  module_exit(dummy_irq_exit);
  
  MODULE_LICENSE("GPL");
  MODULE_AUTHOR("Jiri Kosina");
4f1927dcb   David Howells   Annotate hardware...
61
  module_param_hw(irq, uint, irq, 0444);
54f69b92f   Jiri Kosina   dummy-irq: introd...
62
  MODULE_PARM_DESC(irq, "The IRQ to register for");
da86920f4   Terry Chia   Add MODULE_DESCRI...
63
  MODULE_DESCRIPTION("Dummy IRQ handler driver");