core.c

  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
 13MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
 14MODULE_LICENSE("GPL");
 15MODULE_DESCRIPTION("Apple Soundbus");
 16
 17struct 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}
 29EXPORT_SYMBOL_GPL(soundbus_dev_get);
 30
 31void soundbus_dev_put(struct soundbus_dev *dev)
 32{
 33	if (dev)
 34		put_device(&dev->ofdev.dev);
 35}
 36EXPORT_SYMBOL_GPL(soundbus_dev_put);
 37
 38static 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
 60static 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
109static 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
119static 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 */
129ATTRIBUTE_GROUPS(soundbus_dev);
130static const 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
139int 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}
156EXPORT_SYMBOL_GPL(soundbus_add_one);
157
158void soundbus_remove_one(struct soundbus_dev *dev)
159{
160	of_device_unregister(&dev->ofdev);
161}
162EXPORT_SYMBOL_GPL(soundbus_remove_one);
163
164int 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}
173EXPORT_SYMBOL_GPL(soundbus_register_driver);
174
175void soundbus_unregister_driver(struct soundbus_driver *drv)
176{
177	driver_unregister(&drv->driver);
178}
179EXPORT_SYMBOL_GPL(soundbus_unregister_driver);
180
181static int __init soundbus_init(void)
182{
183	return bus_register(&soundbus_bus_type);
184}
185
186static void __exit soundbus_exit(void)
187{
188	bus_unregister(&soundbus_bus_type);
189}
190
191subsys_initcall(soundbus_init);
192module_exit(soundbus_exit);