xref: /openbmc/linux/sound/ac97_bus.c (revision 8e9356c6)
1 /*
2  * Linux driver model AC97 bus interface
3  *
4  * Author:	Nicolas Pitre
5  * Created:	Jan 14, 2005
6  * Copyright:	(C) MontaVista Software Inc.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  */
13 
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/device.h>
17 #include <linux/string.h>
18 #include <sound/ac97_codec.h>
19 
20 /*
21  * Let drivers decide whether they want to support given codec from their
22  * probe method. Drivers have direct access to the struct snd_ac97
23  * structure and may  decide based on the id field amongst other things.
24  */
25 static int ac97_bus_match(struct device *dev, struct device_driver *drv)
26 {
27 	return 1;
28 }
29 
30 #ifdef CONFIG_PM
31 static int ac97_bus_suspend(struct device *dev, pm_message_t state)
32 {
33 	int ret = 0;
34 
35 	if (dev->driver && dev->driver->suspend)
36 		ret = dev->driver->suspend(dev, state);
37 
38 	return ret;
39 }
40 
41 static int ac97_bus_resume(struct device *dev)
42 {
43 	int ret = 0;
44 
45 	if (dev->driver && dev->driver->resume)
46 		ret = dev->driver->resume(dev);
47 
48 	return ret;
49 }
50 #endif /* CONFIG_PM */
51 
52 struct bus_type ac97_bus_type = {
53 	.name		= "ac97",
54 	.match		= ac97_bus_match,
55 #ifdef CONFIG_PM
56 	.suspend	= ac97_bus_suspend,
57 	.resume		= ac97_bus_resume,
58 #endif /* CONFIG_PM */
59 };
60 
61 static int __init ac97_bus_init(void)
62 {
63 	return bus_register(&ac97_bus_type);
64 }
65 
66 subsys_initcall(ac97_bus_init);
67 
68 static void __exit ac97_bus_exit(void)
69 {
70 	bus_unregister(&ac97_bus_type);
71 }
72 
73 module_exit(ac97_bus_exit);
74 
75 EXPORT_SYMBOL(ac97_bus_type);
76 
77 MODULE_LICENSE("GPL");
78