xref: /linux/sound/aoa/soundbus/core.c (revision 8ca4fc323d2e4ab9dabbdd57633af40b0c7e6af9)
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 "soundbus.h"
10 
11 MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
12 MODULE_LICENSE("GPL");
13 MODULE_DESCRIPTION("Apple Soundbus");
14 
15 struct soundbus_dev *soundbus_dev_get(struct soundbus_dev *dev)
16 {
17 	struct device *tmp;
18 
19 	if (!dev)
20 		return NULL;
21 	tmp = get_device(&dev->ofdev.dev);
22 	if (tmp)
23 		return to_soundbus_device(tmp);
24 	else
25 		return NULL;
26 }
27 EXPORT_SYMBOL_GPL(soundbus_dev_get);
28 
29 void soundbus_dev_put(struct soundbus_dev *dev)
30 {
31 	if (dev)
32 		put_device(&dev->ofdev.dev);
33 }
34 EXPORT_SYMBOL_GPL(soundbus_dev_put);
35 
36 static int soundbus_probe(struct device *dev)
37 {
38 	int error = -ENODEV;
39 	struct soundbus_driver *drv;
40 	struct soundbus_dev *soundbus_dev;
41 
42 	drv = to_soundbus_driver(dev->driver);
43 	soundbus_dev = to_soundbus_device(dev);
44 
45 	if (!drv->probe)
46 		return error;
47 
48 	soundbus_dev_get(soundbus_dev);
49 
50 	error = drv->probe(soundbus_dev);
51 	if (error)
52 		soundbus_dev_put(soundbus_dev);
53 
54 	return error;
55 }
56 
57 
58 static int soundbus_uevent(struct device *dev, struct kobj_uevent_env *env)
59 {
60 	struct soundbus_dev * soundbus_dev;
61 	struct platform_device * of;
62 	const char *compat;
63 	int retval = 0;
64 	int cplen, seen = 0;
65 
66 	if (!dev)
67 		return -ENODEV;
68 
69 	soundbus_dev = to_soundbus_device(dev);
70 	if (!soundbus_dev)
71 		return -ENODEV;
72 
73 	of = &soundbus_dev->ofdev;
74 
75 	/* stuff we want to pass to /sbin/hotplug */
76 	retval = add_uevent_var(env, "OF_NAME=%pOFn", of->dev.of_node);
77 	if (retval)
78 		return retval;
79 
80 	retval = add_uevent_var(env, "OF_TYPE=%s", of_node_get_device_type(of->dev.of_node));
81 	if (retval)
82 		return retval;
83 
84 	/* Since the compatible field can contain pretty much anything
85 	 * it's not really legal to split it out with commas. We split it
86 	 * up using a number of environment variables instead. */
87 
88 	compat = of_get_property(of->dev.of_node, "compatible", &cplen);
89 	while (compat && cplen > 0) {
90 		int tmp = env->buflen;
91 		retval = add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
92 		if (retval)
93 			return retval;
94 		compat += env->buflen - tmp;
95 		cplen -= env->buflen - tmp;
96 		seen += 1;
97 	}
98 
99 	retval = add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
100 	if (retval)
101 		return retval;
102 	retval = add_uevent_var(env, "MODALIAS=%s", soundbus_dev->modalias);
103 
104 	return retval;
105 }
106 
107 static void soundbus_device_remove(struct device *dev)
108 {
109 	struct soundbus_dev * soundbus_dev = to_soundbus_device(dev);
110 	struct soundbus_driver * drv = to_soundbus_driver(dev->driver);
111 
112 	if (dev->driver && drv->remove)
113 		drv->remove(soundbus_dev);
114 	soundbus_dev_put(soundbus_dev);
115 }
116 
117 static void soundbus_device_shutdown(struct device *dev)
118 {
119 	struct soundbus_dev * soundbus_dev = to_soundbus_device(dev);
120 	struct soundbus_driver * drv = to_soundbus_driver(dev->driver);
121 
122 	if (dev->driver && drv->shutdown)
123 		drv->shutdown(soundbus_dev);
124 }
125 
126 /* soundbus_dev_attrs is declared in sysfs.c */
127 ATTRIBUTE_GROUPS(soundbus_dev);
128 static struct bus_type soundbus_bus_type = {
129 	.name		= "aoa-soundbus",
130 	.probe		= soundbus_probe,
131 	.uevent		= soundbus_uevent,
132 	.remove		= soundbus_device_remove,
133 	.shutdown	= soundbus_device_shutdown,
134 	.dev_groups	= soundbus_dev_groups,
135 };
136 
137 int soundbus_add_one(struct soundbus_dev *dev)
138 {
139 	static int devcount;
140 
141 	/* sanity checks */
142 	if (!dev->attach_codec ||
143 	    !dev->ofdev.dev.of_node ||
144 	    dev->pcmname ||
145 	    dev->pcmid != -1) {
146 		printk(KERN_ERR "soundbus: adding device failed sanity check!\n");
147 		return -EINVAL;
148 	}
149 
150 	dev_set_name(&dev->ofdev.dev, "soundbus:%x", ++devcount);
151 	dev->ofdev.dev.bus = &soundbus_bus_type;
152 	return of_device_register(&dev->ofdev);
153 }
154 EXPORT_SYMBOL_GPL(soundbus_add_one);
155 
156 void soundbus_remove_one(struct soundbus_dev *dev)
157 {
158 	of_device_unregister(&dev->ofdev);
159 }
160 EXPORT_SYMBOL_GPL(soundbus_remove_one);
161 
162 int soundbus_register_driver(struct soundbus_driver *drv)
163 {
164 	/* initialize common driver fields */
165 	drv->driver.name = drv->name;
166 	drv->driver.bus = &soundbus_bus_type;
167 
168 	/* register with core */
169 	return driver_register(&drv->driver);
170 }
171 EXPORT_SYMBOL_GPL(soundbus_register_driver);
172 
173 void soundbus_unregister_driver(struct soundbus_driver *drv)
174 {
175 	driver_unregister(&drv->driver);
176 }
177 EXPORT_SYMBOL_GPL(soundbus_unregister_driver);
178 
179 static int __init soundbus_init(void)
180 {
181 	return bus_register(&soundbus_bus_type);
182 }
183 
184 static void __exit soundbus_exit(void)
185 {
186 	bus_unregister(&soundbus_bus_type);
187 }
188 
189 subsys_initcall(soundbus_init);
190 module_exit(soundbus_exit);
191