xref: /linux/sound/aoa/soundbus/core.c (revision c48a7c44a1d02516309015b6134c9bb982e17008)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * soundbus
4  *
5  * Copyright 2006 Johannes Berg <johannes@sipsolutions.net>
6  */
7 
8 #include <linux/module.h>
9 #include <linux/of.h>
10 #include <linux/of_platform.h>
11 #include "soundbus.h"
12 
13 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
14 MODULE_LICENSE("GPL");
15 MODULE_DESCRIPTION("Apple Soundbus");
16 
17 struct soundbus_dev *soundbus_dev_get(struct soundbus_dev *dev)
18 {
19 	struct device *tmp;
20 
21 	if (!dev)
22 		return NULL;
23 	tmp = get_device(&dev->ofdev.dev);
24 	if (tmp)
25 		return to_soundbus_device(tmp);
26 	else
27 		return NULL;
28 }
29 EXPORT_SYMBOL_GPL(soundbus_dev_get);
30 
31 void soundbus_dev_put(struct soundbus_dev *dev)
32 {
33 	if (dev)
34 		put_device(&dev->ofdev.dev);
35 }
36 EXPORT_SYMBOL_GPL(soundbus_dev_put);
37 
38 static int soundbus_probe(struct device *dev)
39 {
40 	int error = -ENODEV;
41 	struct soundbus_driver *drv;
42 	struct soundbus_dev *soundbus_dev;
43 
44 	drv = to_soundbus_driver(dev->driver);
45 	soundbus_dev = to_soundbus_device(dev);
46 
47 	if (!drv->probe)
48 		return error;
49 
50 	soundbus_dev_get(soundbus_dev);
51 
52 	error = drv->probe(soundbus_dev);
53 	if (error)
54 		soundbus_dev_put(soundbus_dev);
55 
56 	return error;
57 }
58 
59 
60 static int soundbus_uevent(const struct device *dev, struct kobj_uevent_env *env)
61 {
62 	const struct soundbus_dev * soundbus_dev;
63 	const struct platform_device * of;
64 	const char *compat;
65 	int retval = 0;
66 	int cplen, seen = 0;
67 
68 	if (!dev)
69 		return -ENODEV;
70 
71 	soundbus_dev = to_soundbus_device(dev);
72 	if (!soundbus_dev)
73 		return -ENODEV;
74 
75 	of = &soundbus_dev->ofdev;
76 
77 	/* stuff we want to pass to /sbin/hotplug */
78 	retval = add_uevent_var(env, "OF_NAME=%pOFn", of->dev.of_node);
79 	if (retval)
80 		return retval;
81 
82 	retval = add_uevent_var(env, "OF_TYPE=%s", of_node_get_device_type(of->dev.of_node));
83 	if (retval)
84 		return retval;
85 
86 	/* Since the compatible field can contain pretty much anything
87 	 * it's not really legal to split it out with commas. We split it
88 	 * up using a number of environment variables instead. */
89 
90 	compat = of_get_property(of->dev.of_node, "compatible", &cplen);
91 	while (compat && cplen > 0) {
92 		int tmp = env->buflen;
93 		retval = add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
94 		if (retval)
95 			return retval;
96 		compat += env->buflen - tmp;
97 		cplen -= env->buflen - tmp;
98 		seen += 1;
99 	}
100 
101 	retval = add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
102 	if (retval)
103 		return retval;
104 	retval = add_uevent_var(env, "MODALIAS=%s", soundbus_dev->modalias);
105 
106 	return retval;
107 }
108 
109 static void soundbus_device_remove(struct device *dev)
110 {
111 	struct soundbus_dev * soundbus_dev = to_soundbus_device(dev);
112 	struct soundbus_driver * drv = to_soundbus_driver(dev->driver);
113 
114 	if (dev->driver && drv->remove)
115 		drv->remove(soundbus_dev);
116 	soundbus_dev_put(soundbus_dev);
117 }
118 
119 static void soundbus_device_shutdown(struct device *dev)
120 {
121 	struct soundbus_dev * soundbus_dev = to_soundbus_device(dev);
122 	struct soundbus_driver * drv = to_soundbus_driver(dev->driver);
123 
124 	if (dev->driver && drv->shutdown)
125 		drv->shutdown(soundbus_dev);
126 }
127 
128 /* soundbus_dev_attrs is declared in sysfs.c */
129 ATTRIBUTE_GROUPS(soundbus_dev);
130 static struct bus_type soundbus_bus_type = {
131 	.name		= "aoa-soundbus",
132 	.probe		= soundbus_probe,
133 	.uevent		= soundbus_uevent,
134 	.remove		= soundbus_device_remove,
135 	.shutdown	= soundbus_device_shutdown,
136 	.dev_groups	= soundbus_dev_groups,
137 };
138 
139 int soundbus_add_one(struct soundbus_dev *dev)
140 {
141 	static int devcount;
142 
143 	/* sanity checks */
144 	if (!dev->attach_codec ||
145 	    !dev->ofdev.dev.of_node ||
146 	    dev->pcmname ||
147 	    dev->pcmid != -1) {
148 		printk(KERN_ERR "soundbus: adding device failed sanity check!\n");
149 		return -EINVAL;
150 	}
151 
152 	dev_set_name(&dev->ofdev.dev, "soundbus:%x", ++devcount);
153 	dev->ofdev.dev.bus = &soundbus_bus_type;
154 	return of_device_register(&dev->ofdev);
155 }
156 EXPORT_SYMBOL_GPL(soundbus_add_one);
157 
158 void soundbus_remove_one(struct soundbus_dev *dev)
159 {
160 	of_device_unregister(&dev->ofdev);
161 }
162 EXPORT_SYMBOL_GPL(soundbus_remove_one);
163 
164 int soundbus_register_driver(struct soundbus_driver *drv)
165 {
166 	/* initialize common driver fields */
167 	drv->driver.name = drv->name;
168 	drv->driver.bus = &soundbus_bus_type;
169 
170 	/* register with core */
171 	return driver_register(&drv->driver);
172 }
173 EXPORT_SYMBOL_GPL(soundbus_register_driver);
174 
175 void soundbus_unregister_driver(struct soundbus_driver *drv)
176 {
177 	driver_unregister(&drv->driver);
178 }
179 EXPORT_SYMBOL_GPL(soundbus_unregister_driver);
180 
181 static int __init soundbus_init(void)
182 {
183 	return bus_register(&soundbus_bus_type);
184 }
185 
186 static void __exit soundbus_exit(void)
187 {
188 	bus_unregister(&soundbus_bus_type);
189 }
190 
191 subsys_initcall(soundbus_init);
192 module_exit(soundbus_exit);
193