xref: /linux/kernel/irq/dummychip.c (revision cc04a46f11ea046ed53e2c832ae29e4790f7e35f)
1 /*
2  * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
3  * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
4  *
5  * This file contains the dummy interrupt chip implementation
6  */
7 #include <linux/interrupt.h>
8 #include <linux/irq.h>
9 #include <linux/export.h>
10 
11 #include "internals.h"
12 
13 /*
14  * What should we do if we get a hw irq event on an illegal vector?
15  * Each architecture has to answer this themself.
16  */
17 static void ack_bad(struct irq_data *data)
18 {
19 	struct irq_desc *desc = irq_data_to_desc(data);
20 
21 	print_irq_desc(data->irq, desc);
22 	ack_bad_irq(data->irq);
23 }
24 
25 /*
26  * NOP functions
27  */
28 static void noop(struct irq_data *data) { }
29 
30 static unsigned int noop_ret(struct irq_data *data)
31 {
32 	return 0;
33 }
34 
35 /*
36  * Generic no controller implementation
37  */
38 struct irq_chip no_irq_chip = {
39 	.name		= "none",
40 	.irq_startup	= noop_ret,
41 	.irq_shutdown	= noop,
42 	.irq_enable	= noop,
43 	.irq_disable	= noop,
44 	.irq_ack	= ack_bad,
45 	.flags		= IRQCHIP_SKIP_SET_WAKE,
46 };
47 
48 /*
49  * Generic dummy implementation which can be used for
50  * real dumb interrupt sources
51  */
52 struct irq_chip dummy_irq_chip = {
53 	.name		= "dummy",
54 	.irq_startup	= noop_ret,
55 	.irq_shutdown	= noop,
56 	.irq_enable	= noop,
57 	.irq_disable	= noop,
58 	.irq_ack	= noop,
59 	.irq_mask	= noop,
60 	.irq_unmask	= noop,
61 	.flags		= IRQCHIP_SKIP_SET_WAKE,
62 };
63 EXPORT_SYMBOL_GPL(dummy_irq_chip);
64