xref: /openbmc/linux/sound/aoa/soundbus/core.c (revision eb3fcf00)
1 /*
2  * soundbus
3  *
4  * Copyright 2006 Johannes Berg <johannes@sipsolutions.net>
5  *
6  * GPL v2, can be found in COPYING.
7  */
8 
9 #include <linux/module.h>
10 #include "soundbus.h"
11 
12 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
13 MODULE_LICENSE("GPL");
14 MODULE_DESCRIPTION("Apple Soundbus");
15 
16 struct soundbus_dev *soundbus_dev_get(struct soundbus_dev *dev)
17 {
18 	struct device *tmp;
19 
20 	if (!dev)
21 		return NULL;
22 	tmp = get_device(&dev->ofdev.dev);
23 	if (tmp)
24 		return to_soundbus_device(tmp);
25 	else
26 		return NULL;
27 }
28 EXPORT_SYMBOL_GPL(soundbus_dev_get);
29 
30 void soundbus_dev_put(struct soundbus_dev *dev)
31 {
32 	if (dev)
33 		put_device(&dev->ofdev.dev);
34 }
35 EXPORT_SYMBOL_GPL(soundbus_dev_put);
36 
37 static int soundbus_probe(struct device *dev)
38 {
39 	int error = -ENODEV;
40 	struct soundbus_driver *drv;
41 	struct soundbus_dev *soundbus_dev;
42 
43 	drv = to_soundbus_driver(dev->driver);
44 	soundbus_dev = to_soundbus_device(dev);
45 
46 	if (!drv->probe)
47 		return error;
48 
49 	soundbus_dev_get(soundbus_dev);
50 
51 	error = drv->probe(soundbus_dev);
52 	if (error)
53 		soundbus_dev_put(soundbus_dev);
54 
55 	return error;
56 }
57 
58 
59 static int soundbus_uevent(struct device *dev, struct kobj_uevent_env *env)
60 {
61 	struct soundbus_dev * soundbus_dev;
62 	struct platform_device * of;
63 	const char *compat;
64 	int retval = 0;
65 	int cplen, seen = 0;
66 
67 	if (!dev)
68 		return -ENODEV;
69 
70 	soundbus_dev = to_soundbus_device(dev);
71 	if (!soundbus_dev)
72 		return -ENODEV;
73 
74 	of = &soundbus_dev->ofdev;
75 
76 	/* stuff we want to pass to /sbin/hotplug */
77 	retval = add_uevent_var(env, "OF_NAME=%s", of->dev.of_node->name);
78 	if (retval)
79 		return retval;
80 
81 	retval = add_uevent_var(env, "OF_TYPE=%s", of->dev.of_node->type);
82 	if (retval)
83 		return retval;
84 
85 	/* Since the compatible field can contain pretty much anything
86 	 * it's not really legal to split it out with commas. We split it
87 	 * up using a number of environment variables instead. */
88 
89 	compat = of_get_property(of->dev.of_node, "compatible", &cplen);
90 	while (compat && cplen > 0) {
91 		int tmp = env->buflen;
92 		retval = add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
93 		if (retval)
94 			return retval;
95 		compat += env->buflen - tmp;
96 		cplen -= env->buflen - tmp;
97 		seen += 1;
98 	}
99 
100 	retval = add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
101 	if (retval)
102 		return retval;
103 	retval = add_uevent_var(env, "MODALIAS=%s", soundbus_dev->modalias);
104 
105 	return retval;
106 }
107 
108 static int soundbus_device_remove(struct device *dev)
109 {
110 	struct soundbus_dev * soundbus_dev = to_soundbus_device(dev);
111 	struct soundbus_driver * drv = to_soundbus_driver(dev->driver);
112 
113 	if (dev->driver && drv->remove)
114 		drv->remove(soundbus_dev);
115 	soundbus_dev_put(soundbus_dev);
116 
117 	return 0;
118 }
119 
120 static void soundbus_device_shutdown(struct device *dev)
121 {
122 	struct soundbus_dev * soundbus_dev = to_soundbus_device(dev);
123 	struct soundbus_driver * drv = to_soundbus_driver(dev->driver);
124 
125 	if (dev->driver && drv->shutdown)
126 		drv->shutdown(soundbus_dev);
127 }
128 
129 /* soundbus_dev_attrs is declared in sysfs.c */
130 ATTRIBUTE_GROUPS(soundbus_dev);
131 static struct bus_type soundbus_bus_type = {
132 	.name		= "aoa-soundbus",
133 	.probe		= soundbus_probe,
134 	.uevent		= soundbus_uevent,
135 	.remove		= soundbus_device_remove,
136 	.shutdown	= soundbus_device_shutdown,
137 	.dev_groups	= soundbus_dev_groups,
138 };
139 
140 int soundbus_add_one(struct soundbus_dev *dev)
141 {
142 	static int devcount;
143 
144 	/* sanity checks */
145 	if (!dev->attach_codec ||
146 	    !dev->ofdev.dev.of_node ||
147 	    dev->pcmname ||
148 	    dev->pcmid != -1) {
149 		printk(KERN_ERR "soundbus: adding device failed sanity check!\n");
150 		return -EINVAL;
151 	}
152 
153 	dev_set_name(&dev->ofdev.dev, "soundbus:%x", ++devcount);
154 	dev->ofdev.dev.bus = &soundbus_bus_type;
155 	return of_device_register(&dev->ofdev);
156 }
157 EXPORT_SYMBOL_GPL(soundbus_add_one);
158 
159 void soundbus_remove_one(struct soundbus_dev *dev)
160 {
161 	of_device_unregister(&dev->ofdev);
162 }
163 EXPORT_SYMBOL_GPL(soundbus_remove_one);
164 
165 int soundbus_register_driver(struct soundbus_driver *drv)
166 {
167 	/* initialize common driver fields */
168 	drv->driver.name = drv->name;
169 	drv->driver.bus = &soundbus_bus_type;
170 
171 	/* register with core */
172 	return driver_register(&drv->driver);
173 }
174 EXPORT_SYMBOL_GPL(soundbus_register_driver);
175 
176 void soundbus_unregister_driver(struct soundbus_driver *drv)
177 {
178 	driver_unregister(&drv->driver);
179 }
180 EXPORT_SYMBOL_GPL(soundbus_unregister_driver);
181 
182 static int __init soundbus_init(void)
183 {
184 	return bus_register(&soundbus_bus_type);
185 }
186 
187 static void __exit soundbus_exit(void)
188 {
189 	bus_unregister(&soundbus_bus_type);
190 }
191 
192 subsys_initcall(soundbus_init);
193 module_exit(soundbus_exit);
194