xref: /openbmc/linux/sound/ac97_bus.c (revision 643d1f7f)
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 #ifdef CONFIG_PM
30 static int ac97_bus_suspend(struct device *dev, pm_message_t state)
31 {
32 	int ret = 0;
33 
34 	if (dev->driver && dev->driver->suspend)
35 		ret = dev->driver->suspend(dev, state);
36 
37 	return ret;
38 }
39 
40 static int ac97_bus_resume(struct device *dev)
41 {
42 	int ret = 0;
43 
44 	if (dev->driver && dev->driver->resume)
45 		ret = dev->driver->resume(dev);
46 
47 	return ret;
48 }
49 #endif /* CONFIG_PM */
50 
51 struct bus_type ac97_bus_type = {
52 	.name		= "ac97",
53 	.match		= ac97_bus_match,
54 #ifdef CONFIG_PM
55 	.suspend	= ac97_bus_suspend,
56 	.resume		= ac97_bus_resume,
57 #endif /* CONFIG_PM */
58 };
59 
60 static int __init ac97_bus_init(void)
61 {
62 	return bus_register(&ac97_bus_type);
63 }
64 
65 subsys_initcall(ac97_bus_init);
66 
67 static void __exit ac97_bus_exit(void)
68 {
69 	bus_unregister(&ac97_bus_type);
70 }
71 
72 module_exit(ac97_bus_exit);
73 
74 EXPORT_SYMBOL(ac97_bus_type);
75 
76 MODULE_LICENSE("GPL");
77