blob: 161746deab4baabb00bebdf4fb0991bbdf693f7f [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * class.c - basic device class management
3 *
4 * Copyright (c) 2002-3 Patrick Mochel
5 * Copyright (c) 2002-3 Open Source Development Labs
6 * Copyright (c) 2003-2004 Greg Kroah-Hartman
7 * Copyright (c) 2003-2004 IBM Corp.
8 *
9 * This file is released under the GPLv2
10 *
11 */
12
Linus Torvalds1da177e2005-04-16 15:20:36 -070013#include <linux/device.h>
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/string.h>
17#include <linux/kdev_t.h>
gregkh@suse.dee9ba6362005-03-15 11:54:21 -080018#include <linux/err.h>
Tim Schmielau4e57b682005-10-30 15:03:48 -080019#include <linux/slab.h>
Kay Sieversedfaa7c2007-05-21 22:08:01 +020020#include <linux/genhd.h>
Dave Youngf75b1c62008-05-28 09:28:39 -070021#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include "base.h"
23
24#define to_class_attr(_attr) container_of(_attr, struct class_attribute, attr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070025
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080026static ssize_t class_attr_show(struct kobject *kobj, struct attribute *attr,
27 char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -070028{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080029 struct class_attribute *class_attr = to_class_attr(attr);
Greg Kroah-Hartman7c714482008-01-22 18:17:41 -050030 struct class_private *cp = to_class(kobj);
Dmitry Torokhov4a0c20b2005-04-29 01:23:47 -050031 ssize_t ret = -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -070032
33 if (class_attr->show)
Greg Kroah-Hartman7c714482008-01-22 18:17:41 -050034 ret = class_attr->show(cp->class, buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -070035 return ret;
36}
37
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080038static ssize_t class_attr_store(struct kobject *kobj, struct attribute *attr,
39 const char *buf, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -070040{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080041 struct class_attribute *class_attr = to_class_attr(attr);
Greg Kroah-Hartman7c714482008-01-22 18:17:41 -050042 struct class_private *cp = to_class(kobj);
Dmitry Torokhov4a0c20b2005-04-29 01:23:47 -050043 ssize_t ret = -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -070044
45 if (class_attr->store)
Greg Kroah-Hartman7c714482008-01-22 18:17:41 -050046 ret = class_attr->store(cp->class, buf, count);
Linus Torvalds1da177e2005-04-16 15:20:36 -070047 return ret;
48}
49
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080050static void class_release(struct kobject *kobj)
Linus Torvalds1da177e2005-04-16 15:20:36 -070051{
Greg Kroah-Hartman7c714482008-01-22 18:17:41 -050052 struct class_private *cp = to_class(kobj);
53 struct class *class = cp->class;
Linus Torvalds1da177e2005-04-16 15:20:36 -070054
55 pr_debug("class '%s': release.\n", class->name);
56
57 if (class->class_release)
58 class->class_release(class);
59 else
60 pr_debug("class '%s' does not have a release() function, "
61 "be careful\n", class->name);
62}
63
64static struct sysfs_ops class_sysfs_ops = {
65 .show = class_attr_show,
66 .store = class_attr_store,
67};
68
Greg Kroah-Hartmanadc56802007-10-11 10:47:49 -060069static struct kobj_type class_ktype = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 .sysfs_ops = &class_sysfs_ops,
71 .release = class_release,
72};
73
Greg Kroah-Hartman1fbfee62008-05-28 09:28:39 -070074/* Hotplug events for classes go to the class class_subsys */
Greg Kroah-Hartman443dbf92007-10-29 23:22:26 -050075static struct kset *class_kset;
Linus Torvalds1da177e2005-04-16 15:20:36 -070076
77
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080078int class_create_file(struct class *cls, const struct class_attribute *attr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070079{
80 int error;
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080081 if (cls)
Greg Kroah-Hartman1fbfee62008-05-28 09:28:39 -070082 error = sysfs_create_file(&cls->p->class_subsys.kobj,
83 &attr->attr);
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080084 else
Linus Torvalds1da177e2005-04-16 15:20:36 -070085 error = -EINVAL;
86 return error;
87}
88
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080089void class_remove_file(struct class *cls, const struct class_attribute *attr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070090{
91 if (cls)
Greg Kroah-Hartman1fbfee62008-05-28 09:28:39 -070092 sysfs_remove_file(&cls->p->class_subsys.kobj, &attr->attr);
Linus Torvalds1da177e2005-04-16 15:20:36 -070093}
94
Greg Kroah-Hartman17407572006-05-02 16:59:59 +020095static struct class *class_get(struct class *cls)
Linus Torvalds1da177e2005-04-16 15:20:36 -070096{
97 if (cls)
Greg Kroah-Hartman1fbfee62008-05-28 09:28:39 -070098 kset_get(&cls->p->class_subsys);
Greg Kroah-Hartman7c714482008-01-22 18:17:41 -050099 return cls;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100}
101
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800102static void class_put(struct class *cls)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103{
Greg Kroah-Hartman51d172d2005-10-27 22:25:43 -0700104 if (cls)
Greg Kroah-Hartman1fbfee62008-05-28 09:28:39 -0700105 kset_put(&cls->p->class_subsys);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106}
107
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800108static int add_class_attrs(struct class *cls)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109{
110 int i;
111 int error = 0;
112
113 if (cls->class_attrs) {
114 for (i = 0; attr_name(cls->class_attrs[i]); i++) {
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800115 error = class_create_file(cls, &cls->class_attrs[i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 if (error)
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800117 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 }
119 }
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800120done:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121 return error;
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800122error:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123 while (--i >= 0)
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800124 class_remove_file(cls, &cls->class_attrs[i]);
125 goto done;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126}
127
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800128static void remove_class_attrs(struct class *cls)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129{
130 int i;
131
132 if (cls->class_attrs) {
133 for (i = 0; attr_name(cls->class_attrs[i]); i++)
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800134 class_remove_file(cls, &cls->class_attrs[i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135 }
136}
137
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200138static void klist_class_dev_get(struct klist_node *n)
139{
140 struct device *dev = container_of(n, struct device, knode_class);
141
142 get_device(dev);
143}
144
145static void klist_class_dev_put(struct klist_node *n)
146{
147 struct device *dev = container_of(n, struct device, knode_class);
148
149 put_device(dev);
150}
151
Matthew Wilcoxd2a3b912008-05-28 09:28:39 -0700152int __class_register(struct class *cls, struct lock_class_key *key)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153{
Greg Kroah-Hartman7c714482008-01-22 18:17:41 -0500154 struct class_private *cp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 int error;
156
157 pr_debug("device class '%s': registering\n", cls->name);
158
Greg Kroah-Hartman7c714482008-01-22 18:17:41 -0500159 cp = kzalloc(sizeof(*cp), GFP_KERNEL);
160 if (!cp)
161 return -ENOMEM;
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200162 klist_init(&cp->class_devices, klist_class_dev_get, klist_class_dev_put);
Greg Kroah-Hartman184f1f72008-05-28 09:28:39 -0700163 INIT_LIST_HEAD(&cp->class_interfaces);
Greg Kroah-Hartman7c714482008-01-22 18:17:41 -0500164 kset_init(&cp->class_dirs);
Dave Youngf75b1c62008-05-28 09:28:39 -0700165 __mutex_init(&cp->class_mutex, "struct class mutex", key);
Greg Kroah-Hartman1fbfee62008-05-28 09:28:39 -0700166 error = kobject_set_name(&cp->class_subsys.kobj, "%s", cls->name);
Greg Kroah-Hartman7c714482008-01-22 18:17:41 -0500167 if (error) {
168 kfree(cp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 return error;
Greg Kroah-Hartman7c714482008-01-22 18:17:41 -0500170 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171
Dan Williamse105b8b2008-04-21 10:51:07 -0700172 /* set the default /sys/dev directory for devices of this class */
173 if (!cls->dev_kobj)
174 cls->dev_kobj = sysfs_dev_char_kobj;
175
Greg Kroah-Hartman4e886c22008-01-27 12:12:43 -0800176#if defined(CONFIG_SYSFS_DEPRECATED) && defined(CONFIG_BLOCK)
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200177 /* let the block class directory show up in the root of sysfs */
178 if (cls != &block_class)
Greg Kroah-Hartman1fbfee62008-05-28 09:28:39 -0700179 cp->class_subsys.kobj.kset = class_kset;
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200180#else
Greg Kroah-Hartman1fbfee62008-05-28 09:28:39 -0700181 cp->class_subsys.kobj.kset = class_kset;
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200182#endif
Greg Kroah-Hartman1fbfee62008-05-28 09:28:39 -0700183 cp->class_subsys.kobj.ktype = &class_ktype;
Greg Kroah-Hartman7c714482008-01-22 18:17:41 -0500184 cp->class = cls;
185 cls->p = cp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186
Greg Kroah-Hartman1fbfee62008-05-28 09:28:39 -0700187 error = kset_register(&cp->class_subsys);
Greg Kroah-Hartman7c714482008-01-22 18:17:41 -0500188 if (error) {
189 kfree(cp);
190 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191 }
Greg Kroah-Hartman7c714482008-01-22 18:17:41 -0500192 error = add_class_attrs(class_get(cls));
193 class_put(cls);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 return error;
195}
Matthew Wilcoxd2a3b912008-05-28 09:28:39 -0700196EXPORT_SYMBOL_GPL(__class_register);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800198void class_unregister(struct class *cls)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199{
200 pr_debug("device class '%s': unregistering\n", cls->name);
201 remove_class_attrs(cls);
Greg Kroah-Hartman1fbfee62008-05-28 09:28:39 -0700202 kset_unregister(&cls->p->class_subsys);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203}
204
gregkh@suse.dee9ba6362005-03-15 11:54:21 -0800205static void class_create_release(struct class *cls)
206{
Harvey Harrison2b3a3022008-03-04 16:41:05 -0800207 pr_debug("%s called for %s\n", __func__, cls->name);
gregkh@suse.dee9ba6362005-03-15 11:54:21 -0800208 kfree(cls);
209}
210
gregkh@suse.de2fc68442005-03-23 10:02:56 -0800211/**
212 * class_create - create a struct class structure
213 * @owner: pointer to the module that is to "own" this struct class
214 * @name: pointer to a string for the name of this class.
Randy Dunlap0e241ff2008-07-24 16:58:42 -0700215 * @key: the lock_class_key for this class; used by mutex lock debugging
gregkh@suse.de2fc68442005-03-23 10:02:56 -0800216 *
217 * This is used to create a struct class pointer that can then be used
Kay Sieversc3b19ff2008-03-12 20:47:35 +0100218 * in calls to device_create().
gregkh@suse.de2fc68442005-03-23 10:02:56 -0800219 *
220 * Note, the pointer created here is to be destroyed when finished by
221 * making a call to class_destroy().
222 */
Matthew Wilcoxd2a3b912008-05-28 09:28:39 -0700223struct class *__class_create(struct module *owner, const char *name,
224 struct lock_class_key *key)
gregkh@suse.dee9ba6362005-03-15 11:54:21 -0800225{
226 struct class *cls;
227 int retval;
228
Jiri Slaby4aed0642005-09-13 01:25:01 -0700229 cls = kzalloc(sizeof(*cls), GFP_KERNEL);
gregkh@suse.dee9ba6362005-03-15 11:54:21 -0800230 if (!cls) {
231 retval = -ENOMEM;
232 goto error;
233 }
gregkh@suse.dee9ba6362005-03-15 11:54:21 -0800234
235 cls->name = name;
236 cls->owner = owner;
237 cls->class_release = class_create_release;
gregkh@suse.dee9ba6362005-03-15 11:54:21 -0800238
Matthew Wilcoxd2a3b912008-05-28 09:28:39 -0700239 retval = __class_register(cls, key);
gregkh@suse.dee9ba6362005-03-15 11:54:21 -0800240 if (retval)
241 goto error;
242
243 return cls;
244
245error:
246 kfree(cls);
247 return ERR_PTR(retval);
248}
Matthew Wilcoxd2a3b912008-05-28 09:28:39 -0700249EXPORT_SYMBOL_GPL(__class_create);
gregkh@suse.dee9ba6362005-03-15 11:54:21 -0800250
gregkh@suse.de2fc68442005-03-23 10:02:56 -0800251/**
252 * class_destroy - destroys a struct class structure
Rolf Eike Beer92a0f862006-09-29 01:59:13 -0700253 * @cls: pointer to the struct class that is to be destroyed
gregkh@suse.de2fc68442005-03-23 10:02:56 -0800254 *
255 * Note, the pointer to be destroyed must have been created with a call
256 * to class_create().
257 */
gregkh@suse.dee9ba6362005-03-15 11:54:21 -0800258void class_destroy(struct class *cls)
259{
260 if ((cls == NULL) || (IS_ERR(cls)))
261 return;
262
263 class_unregister(cls);
264}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265
Kay Sievers805fab42006-09-14 11:23:28 +0200266#ifdef CONFIG_SYSFS_DEPRECATED
267char *make_class_name(const char *name, struct kobject *kobj)
268{
269 char *class_name;
270 int size;
271
272 size = strlen(name) + strlen(kobject_name(kobj)) + 2;
273
274 class_name = kmalloc(size, GFP_KERNEL);
275 if (!class_name)
Cornelia Huckcb360bb2006-11-27 10:35:05 +0100276 return NULL;
Kay Sievers805fab42006-09-14 11:23:28 +0200277
278 strcpy(class_name, name);
279 strcat(class_name, ":");
280 strcat(class_name, kobject_name(kobj));
281 return class_name;
282}
Kay Sievers805fab42006-09-14 11:23:28 +0200283#endif
284
Dave Youngfd048972008-01-22 15:27:08 +0800285/**
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200286 * class_dev_iter_init - initialize class device iterator
287 * @iter: class iterator to initialize
288 * @class: the class we wanna iterate over
289 * @start: the device to start iterating from, if any
290 * @type: device_type of the devices to iterate over, NULL for all
291 *
292 * Initialize class iterator @iter such that it iterates over devices
293 * of @class. If @start is set, the list iteration will start there,
294 * otherwise if it is NULL, the iteration starts at the beginning of
295 * the list.
296 */
297void class_dev_iter_init(struct class_dev_iter *iter, struct class *class,
298 struct device *start, const struct device_type *type)
299{
300 struct klist_node *start_knode = NULL;
301
302 if (start)
303 start_knode = &start->knode_class;
304 klist_iter_init_node(&class->p->class_devices, &iter->ki, start_knode);
305 iter->type = type;
306}
307EXPORT_SYMBOL_GPL(class_dev_iter_init);
308
309/**
310 * class_dev_iter_next - iterate to the next device
311 * @iter: class iterator to proceed
312 *
313 * Proceed @iter to the next device and return it. Returns NULL if
314 * iteration is complete.
315 *
316 * The returned device is referenced and won't be released till
317 * iterator is proceed to the next device or exited. The caller is
318 * free to do whatever it wants to do with the device including
319 * calling back into class code.
320 */
321struct device *class_dev_iter_next(struct class_dev_iter *iter)
322{
323 struct klist_node *knode;
324 struct device *dev;
325
326 while (1) {
327 knode = klist_next(&iter->ki);
328 if (!knode)
329 return NULL;
330 dev = container_of(knode, struct device, knode_class);
331 if (!iter->type || iter->type == dev->type)
332 return dev;
333 }
334}
335EXPORT_SYMBOL_GPL(class_dev_iter_next);
336
337/**
338 * class_dev_iter_exit - finish iteration
339 * @iter: class iterator to finish
340 *
341 * Finish an iteration. Always call this function after iteration is
342 * complete whether the iteration ran till the end or not.
343 */
344void class_dev_iter_exit(struct class_dev_iter *iter)
345{
346 klist_iter_exit(&iter->ki);
347}
348EXPORT_SYMBOL_GPL(class_dev_iter_exit);
349
350/**
Dave Youngfd048972008-01-22 15:27:08 +0800351 * class_for_each_device - device iterator
352 * @class: the class we're iterating
Greg Kroah-Hartman93562b52008-05-22 17:21:08 -0400353 * @start: the device to start with in the list, if any.
Dave Youngfd048972008-01-22 15:27:08 +0800354 * @data: data for the callback
355 * @fn: function to be called for each device
356 *
357 * Iterate over @class's list of devices, and call @fn for each,
Greg Kroah-Hartman93562b52008-05-22 17:21:08 -0400358 * passing it @data. If @start is set, the list iteration will start
359 * there, otherwise if it is NULL, the iteration starts at the
360 * beginning of the list.
Dave Youngfd048972008-01-22 15:27:08 +0800361 *
362 * We check the return of @fn each time. If it returns anything
363 * other than 0, we break out and return that value.
364 *
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200365 * @fn is allowed to do anything including calling back into class
366 * code. There's no locking restriction.
Dave Youngfd048972008-01-22 15:27:08 +0800367 */
Greg Kroah-Hartman93562b52008-05-22 17:21:08 -0400368int class_for_each_device(struct class *class, struct device *start,
369 void *data, int (*fn)(struct device *, void *))
Dave Youngfd048972008-01-22 15:27:08 +0800370{
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200371 struct class_dev_iter iter;
Dave Youngfd048972008-01-22 15:27:08 +0800372 struct device *dev;
373 int error = 0;
374
375 if (!class)
376 return -EINVAL;
David Brownell7c225032008-08-06 18:52:44 -0700377 if (!class->p) {
378 WARN(1, "%s called for class '%s' before it was initialized",
379 __func__, class->name);
380 return -EINVAL;
381 }
382
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200383 class_dev_iter_init(&iter, class, start, NULL);
384 while ((dev = class_dev_iter_next(&iter))) {
Greg Kroah-Hartman93562b52008-05-22 17:21:08 -0400385 error = fn(dev, data);
Dave Youngfd048972008-01-22 15:27:08 +0800386 if (error)
387 break;
388 }
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200389 class_dev_iter_exit(&iter);
Dave Youngfd048972008-01-22 15:27:08 +0800390
391 return error;
392}
393EXPORT_SYMBOL_GPL(class_for_each_device);
394
395/**
396 * class_find_device - device iterator for locating a particular device
397 * @class: the class we're iterating
Greg Kroah-Hartman695794a2008-05-22 17:21:08 -0400398 * @start: Device to begin with
Dave Youngfd048972008-01-22 15:27:08 +0800399 * @data: data for the match function
400 * @match: function to check device
401 *
402 * This is similar to the class_for_each_dev() function above, but it
403 * returns a reference to a device that is 'found' for later use, as
404 * determined by the @match callback.
405 *
406 * The callback should return 0 if the device doesn't match and non-zero
407 * if it does. If the callback returns non-zero, this function will
408 * return to the caller and not iterate over any more devices.
Randy Dunlapa63ca8f2008-01-30 11:51:08 -0800409 *
Dave Youngfd048972008-01-22 15:27:08 +0800410 * Note, you will need to drop the reference with put_device() after use.
411 *
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200412 * @fn is allowed to do anything including calling back into class
413 * code. There's no locking restriction.
Dave Youngfd048972008-01-22 15:27:08 +0800414 */
Greg Kroah-Hartman695794a2008-05-22 17:21:08 -0400415struct device *class_find_device(struct class *class, struct device *start,
416 void *data,
417 int (*match)(struct device *, void *))
Dave Youngfd048972008-01-22 15:27:08 +0800418{
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200419 struct class_dev_iter iter;
Dave Youngfd048972008-01-22 15:27:08 +0800420 struct device *dev;
Dave Youngfd048972008-01-22 15:27:08 +0800421
422 if (!class)
423 return NULL;
David Brownell7c225032008-08-06 18:52:44 -0700424 if (!class->p) {
425 WARN(1, "%s called for class '%s' before it was initialized",
426 __func__, class->name);
427 return NULL;
428 }
Dave Youngfd048972008-01-22 15:27:08 +0800429
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200430 class_dev_iter_init(&iter, class, start, NULL);
431 while ((dev = class_dev_iter_next(&iter))) {
Greg Kroah-Hartman695794a2008-05-22 17:21:08 -0400432 if (match(dev, data)) {
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200433 get_device(dev);
Dave Youngfd048972008-01-22 15:27:08 +0800434 break;
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200435 }
Dave Youngfd048972008-01-22 15:27:08 +0800436 }
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200437 class_dev_iter_exit(&iter);
Dave Youngfd048972008-01-22 15:27:08 +0800438
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200439 return dev;
Dave Youngfd048972008-01-22 15:27:08 +0800440}
441EXPORT_SYMBOL_GPL(class_find_device);
442
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443int class_interface_register(struct class_interface *class_intf)
444{
445 struct class *parent;
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200446 struct class_dev_iter iter;
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200447 struct device *dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448
449 if (!class_intf || !class_intf->class)
450 return -ENODEV;
451
452 parent = class_get(class_intf->class);
453 if (!parent)
454 return -EINVAL;
455
Dave Youngf75b1c62008-05-28 09:28:39 -0700456 mutex_lock(&parent->p->class_mutex);
Greg Kroah-Hartman184f1f72008-05-28 09:28:39 -0700457 list_add_tail(&class_intf->node, &parent->p->class_interfaces);
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200458 if (class_intf->add_dev) {
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200459 class_dev_iter_init(&iter, parent, NULL, NULL);
460 while ((dev = class_dev_iter_next(&iter)))
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200461 class_intf->add_dev(dev, class_intf);
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200462 class_dev_iter_exit(&iter);
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200463 }
Dave Youngf75b1c62008-05-28 09:28:39 -0700464 mutex_unlock(&parent->p->class_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465
466 return 0;
467}
468
469void class_interface_unregister(struct class_interface *class_intf)
470{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800471 struct class *parent = class_intf->class;
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200472 struct class_dev_iter iter;
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200473 struct device *dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474
475 if (!parent)
476 return;
477
Dave Youngf75b1c62008-05-28 09:28:39 -0700478 mutex_lock(&parent->p->class_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479 list_del_init(&class_intf->node);
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200480 if (class_intf->remove_dev) {
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200481 class_dev_iter_init(&iter, parent, NULL, NULL);
482 while ((dev = class_dev_iter_next(&iter)))
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200483 class_intf->remove_dev(dev, class_intf);
Tejun Heo5a3ceb82008-08-25 19:50:19 +0200484 class_dev_iter_exit(&iter);
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200485 }
Dave Youngf75b1c62008-05-28 09:28:39 -0700486 mutex_unlock(&parent->p->class_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487
488 class_put(parent);
489}
490
Jean Delvare46227092009-08-04 12:55:34 +0200491struct class_compat {
492 struct kobject *kobj;
493};
494
495/**
496 * class_compat_register - register a compatibility class
497 * @name: the name of the class
498 *
499 * Compatibility class are meant as a temporary user-space compatibility
500 * workaround when converting a family of class devices to a bus devices.
501 */
502struct class_compat *class_compat_register(const char *name)
503{
504 struct class_compat *cls;
505
506 cls = kmalloc(sizeof(struct class_compat), GFP_KERNEL);
507 if (!cls)
508 return NULL;
509 cls->kobj = kobject_create_and_add(name, &class_kset->kobj);
510 if (!cls->kobj) {
511 kfree(cls);
512 return NULL;
513 }
514 return cls;
515}
516EXPORT_SYMBOL_GPL(class_compat_register);
517
518/**
519 * class_compat_unregister - unregister a compatibility class
520 * @cls: the class to unregister
521 */
522void class_compat_unregister(struct class_compat *cls)
523{
524 kobject_put(cls->kobj);
525 kfree(cls);
526}
527EXPORT_SYMBOL_GPL(class_compat_unregister);
528
529/**
530 * class_compat_create_link - create a compatibility class device link to
531 * a bus device
532 * @cls: the compatibility class
533 * @dev: the target bus device
534 * @device_link: an optional device to which a "device" link should be created
535 */
536int class_compat_create_link(struct class_compat *cls, struct device *dev,
537 struct device *device_link)
538{
539 int error;
540
541 error = sysfs_create_link(cls->kobj, &dev->kobj, dev_name(dev));
542 if (error)
543 return error;
544
545 /*
546 * Optionally add a "device" link (typically to the parent), as a
547 * class device would have one and we want to provide as much
548 * backwards compatibility as possible.
549 */
550 if (device_link) {
551 error = sysfs_create_link(&dev->kobj, &device_link->kobj,
552 "device");
553 if (error)
554 sysfs_remove_link(cls->kobj, dev_name(dev));
555 }
556
557 return error;
558}
559EXPORT_SYMBOL_GPL(class_compat_create_link);
560
561/**
562 * class_compat_remove_link - remove a compatibility class device link to
563 * a bus device
564 * @cls: the compatibility class
565 * @dev: the target bus device
566 * @device_link: an optional device to which a "device" link was previously
567 * created
568 */
569void class_compat_remove_link(struct class_compat *cls, struct device *dev,
570 struct device *device_link)
571{
572 if (device_link)
573 sysfs_remove_link(&dev->kobj, "device");
574 sysfs_remove_link(cls->kobj, dev_name(dev));
575}
576EXPORT_SYMBOL_GPL(class_compat_remove_link);
577
Linus Torvalds1da177e2005-04-16 15:20:36 -0700578int __init classes_init(void)
579{
Greg Kroah-Hartman443dbf92007-10-29 23:22:26 -0500580 class_kset = kset_create_and_add("class", NULL, NULL);
581 if (!class_kset)
582 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583 return 0;
584}
585
586EXPORT_SYMBOL_GPL(class_create_file);
587EXPORT_SYMBOL_GPL(class_remove_file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588EXPORT_SYMBOL_GPL(class_unregister);
gregkh@suse.dee9ba6362005-03-15 11:54:21 -0800589EXPORT_SYMBOL_GPL(class_destroy);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591EXPORT_SYMBOL_GPL(class_interface_register);
592EXPORT_SYMBOL_GPL(class_interface_unregister);