xref: /linux/sound/aoa/soundbus/core.c (revision a7edd0e676d51145ae634a2acf7a447e319200fa)
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, char **envp, int num_envp,
60 			   char *buffer, int buffer_size)
61 {
62 	struct soundbus_dev * soundbus_dev;
63 	struct of_device * of;
64 	char *scratch;
65 	const char *compat;
66 	int i = 0;
67 	int length, cplen, seen = 0;
68 
69 	if (!dev)
70 		return -ENODEV;
71 
72 	soundbus_dev = to_soundbus_device(dev);
73 	if (!soundbus_dev)
74 		return -ENODEV;
75 
76 	of = &soundbus_dev->ofdev;
77 
78 	/* stuff we want to pass to /sbin/hotplug */
79 	envp[i++] = scratch = buffer;
80 	length = scnprintf (scratch, buffer_size, "OF_NAME=%s", of->node->name);
81 	++length;
82 	buffer_size -= length;
83 	if ((buffer_size <= 0) || (i >= num_envp))
84 		return -ENOMEM;
85 	scratch += length;
86 
87 	envp[i++] = scratch;
88 	length = scnprintf (scratch, buffer_size, "OF_TYPE=%s", of->node->type);
89 	++length;
90 	buffer_size -= length;
91 	if ((buffer_size <= 0) || (i >= num_envp))
92 		return -ENOMEM;
93 	scratch += length;
94 
95 	/* Since the compatible field can contain pretty much anything
96 	 * it's not really legal to split it out with commas. We split it
97 	 * up using a number of environment variables instead. */
98 
99 	compat = get_property(of->node, "compatible", &cplen);
100 	while (compat && cplen > 0) {
101 		envp[i++] = scratch;
102 		length = scnprintf (scratch, buffer_size,
103 				     "OF_COMPATIBLE_%d=%s", seen, compat);
104 		++length;
105 		buffer_size -= length;
106 		if ((buffer_size <= 0) || (i >= num_envp))
107 			return -ENOMEM;
108 		scratch += length;
109 		length = strlen (compat) + 1;
110 		compat += length;
111 		cplen -= length;
112 		seen++;
113 	}
114 
115 	envp[i++] = scratch;
116 	length = scnprintf (scratch, buffer_size, "OF_COMPATIBLE_N=%d", seen);
117 	++length;
118 	buffer_size -= length;
119 	if ((buffer_size <= 0) || (i >= num_envp))
120 		return -ENOMEM;
121 	scratch += length;
122 
123 	envp[i++] = scratch;
124 	length = scnprintf (scratch, buffer_size, "MODALIAS=%s",
125 			soundbus_dev->modalias);
126 
127 	buffer_size -= length;
128 	if ((buffer_size <= 0) || (i >= num_envp))
129 		return -ENOMEM;
130 
131 	envp[i] = NULL;
132 
133 	return 0;
134 }
135 
136 static int soundbus_device_remove(struct device *dev)
137 {
138 	struct soundbus_dev * soundbus_dev = to_soundbus_device(dev);
139 	struct soundbus_driver * drv = to_soundbus_driver(dev->driver);
140 
141 	if (dev->driver && drv->remove)
142 		drv->remove(soundbus_dev);
143 	soundbus_dev_put(soundbus_dev);
144 
145 	return 0;
146 }
147 
148 static void soundbus_device_shutdown(struct device *dev)
149 {
150 	struct soundbus_dev * soundbus_dev = to_soundbus_device(dev);
151 	struct soundbus_driver * drv = to_soundbus_driver(dev->driver);
152 
153 	if (dev->driver && drv->shutdown)
154 		drv->shutdown(soundbus_dev);
155 }
156 
157 #ifdef CONFIG_PM
158 
159 static int soundbus_device_suspend(struct device *dev, pm_message_t state)
160 {
161 	struct soundbus_dev * soundbus_dev = to_soundbus_device(dev);
162 	struct soundbus_driver * drv = to_soundbus_driver(dev->driver);
163 
164 	if (dev->driver && drv->suspend)
165 		return drv->suspend(soundbus_dev, state);
166 	return 0;
167 }
168 
169 static int soundbus_device_resume(struct device * dev)
170 {
171 	struct soundbus_dev * soundbus_dev = to_soundbus_device(dev);
172 	struct soundbus_driver * drv = to_soundbus_driver(dev->driver);
173 
174 	if (dev->driver && drv->resume)
175 		return drv->resume(soundbus_dev);
176 	return 0;
177 }
178 
179 #endif /* CONFIG_PM */
180 
181 extern struct device_attribute soundbus_dev_attrs[];
182 
183 static struct bus_type soundbus_bus_type = {
184 	.name		= "aoa-soundbus",
185 	.probe		= soundbus_probe,
186 	.uevent		= soundbus_uevent,
187 	.remove		= soundbus_device_remove,
188 	.shutdown	= soundbus_device_shutdown,
189 #ifdef CONFIG_PM
190 	.suspend	= soundbus_device_suspend,
191 	.resume		= soundbus_device_resume,
192 #endif
193 	.dev_attrs	= soundbus_dev_attrs,
194 };
195 
196 int soundbus_add_one(struct soundbus_dev *dev)
197 {
198 	static int devcount;
199 
200 	/* sanity checks */
201 	if (!dev->attach_codec ||
202 	    !dev->ofdev.node ||
203 	    dev->pcmname ||
204 	    dev->pcmid != -1) {
205 		printk(KERN_ERR "soundbus: adding device failed sanity check!\n");
206 		return -EINVAL;
207 	}
208 
209 	snprintf(dev->ofdev.dev.bus_id, BUS_ID_SIZE, "soundbus:%x", ++devcount);
210 	dev->ofdev.dev.bus = &soundbus_bus_type;
211 	return of_device_register(&dev->ofdev);
212 }
213 EXPORT_SYMBOL_GPL(soundbus_add_one);
214 
215 void soundbus_remove_one(struct soundbus_dev *dev)
216 {
217 	of_device_unregister(&dev->ofdev);
218 }
219 EXPORT_SYMBOL_GPL(soundbus_remove_one);
220 
221 int soundbus_register_driver(struct soundbus_driver *drv)
222 {
223 	/* initialize common driver fields */
224 	drv->driver.name = drv->name;
225 	drv->driver.bus = &soundbus_bus_type;
226 
227 	/* register with core */
228 	return driver_register(&drv->driver);
229 }
230 EXPORT_SYMBOL_GPL(soundbus_register_driver);
231 
232 void soundbus_unregister_driver(struct soundbus_driver *drv)
233 {
234 	driver_unregister(&drv->driver);
235 }
236 EXPORT_SYMBOL_GPL(soundbus_unregister_driver);
237 
238 static int __init soundbus_init(void)
239 {
240 	return bus_register(&soundbus_bus_type);
241 }
242 
243 static void __exit soundbus_exit(void)
244 {
245 	bus_unregister(&soundbus_bus_type);
246 }
247 
248 subsys_initcall(soundbus_init);
249 module_exit(soundbus_exit);
250