xref: /linux/sound/ac97_bus.c (revision b454cc6636d254fbf6049b73e9560aee76fb04a3)
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 
19 /*
20  * Let drivers decide whether they want to support given codec from their
21  * probe method.  Drivers have direct access to the struct snd_ac97 structure and may
22  * decide based on the id field amongst other things.
23  */
24 static int ac97_bus_match(struct device *dev, struct device_driver *drv)
25 {
26 	return 1;
27 }
28 
29 static int ac97_bus_suspend(struct device *dev, pm_message_t state)
30 {
31 	int ret = 0;
32 
33 	if (dev->driver && dev->driver->suspend)
34 		ret = dev->driver->suspend(dev, state);
35 
36 	return ret;
37 }
38 
39 static int ac97_bus_resume(struct device *dev)
40 {
41 	int ret = 0;
42 
43 	if (dev->driver && dev->driver->resume)
44 		ret = dev->driver->resume(dev);
45 
46 	return ret;
47 }
48 
49 struct bus_type ac97_bus_type = {
50 	.name		= "ac97",
51 	.match		= ac97_bus_match,
52 	.suspend	= ac97_bus_suspend,
53 	.resume		= ac97_bus_resume,
54 };
55 
56 static int __init ac97_bus_init(void)
57 {
58 	return bus_register(&ac97_bus_type);
59 }
60 
61 subsys_initcall(ac97_bus_init);
62 
63 static void __exit ac97_bus_exit(void)
64 {
65 	bus_unregister(&ac97_bus_type);
66 }
67 
68 module_exit(ac97_bus_exit);
69 
70 EXPORT_SYMBOL(ac97_bus_type);
71 
72 MODULE_LICENSE("GPL");
73