blob: c1343414d285e29f57fe17e089e635be20af3aed [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * drivers/base/core.c - core driver model code (device registration, etc)
3 *
4 * Copyright (c) 2002-3 Patrick Mochel
5 * Copyright (c) 2002-3 Open Source Development Labs
Greg Kroah-Hartman64bb5d22006-06-28 16:19:58 -07006 * Copyright (c) 2006 Greg Kroah-Hartman <gregkh@suse.de>
7 * Copyright (c) 2006 Novell, Inc.
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 *
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/err.h>
15#include <linux/init.h>
16#include <linux/module.h>
17#include <linux/slab.h>
18#include <linux/string.h>
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -070019#include <linux/kdev_t.h>
Benjamin Herrenschmidt116af372006-10-25 13:44:59 +100020#include <linux/notifier.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021
22#include <asm/semaphore.h>
23
24#include "base.h"
25#include "power/power.h"
26
27int (*platform_notify)(struct device * dev) = NULL;
28int (*platform_notify_remove)(struct device * dev) = NULL;
29
30/*
31 * sysfs bindings for devices.
32 */
33
Alan Stern3e956372006-06-16 17:10:48 -040034/**
35 * dev_driver_string - Return a device's driver name, if at all possible
36 * @dev: struct device to get the name of
37 *
38 * Will return the device's driver's name if it is bound to a device. If
39 * the device is not bound to a device, it will return the name of the bus
40 * it is attached to. If it is not attached to a bus either, an empty
41 * string will be returned.
42 */
43const char *dev_driver_string(struct device *dev)
44{
45 return dev->driver ? dev->driver->name :
Jean Delvarea456b702007-03-09 16:33:10 +010046 (dev->bus ? dev->bus->name :
47 (dev->class ? dev->class->name : ""));
Alan Stern3e956372006-06-16 17:10:48 -040048}
Matthew Wilcox310a9222006-09-23 23:35:04 -060049EXPORT_SYMBOL(dev_driver_string);
Alan Stern3e956372006-06-16 17:10:48 -040050
Linus Torvalds1da177e2005-04-16 15:20:36 -070051#define to_dev(obj) container_of(obj, struct device, kobj)
52#define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr)
53
Linus Torvalds1da177e2005-04-16 15:20:36 -070054static ssize_t
55dev_attr_show(struct kobject * kobj, struct attribute * attr, char * buf)
56{
57 struct device_attribute * dev_attr = to_dev_attr(attr);
58 struct device * dev = to_dev(kobj);
Dmitry Torokhov4a0c20b2005-04-29 01:23:47 -050059 ssize_t ret = -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -070060
61 if (dev_attr->show)
Yani Ioannou54b6f352005-05-17 06:39:34 -040062 ret = dev_attr->show(dev, dev_attr, buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 return ret;
64}
65
66static ssize_t
67dev_attr_store(struct kobject * kobj, struct attribute * attr,
68 const char * buf, size_t count)
69{
70 struct device_attribute * dev_attr = to_dev_attr(attr);
71 struct device * dev = to_dev(kobj);
Dmitry Torokhov4a0c20b2005-04-29 01:23:47 -050072 ssize_t ret = -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -070073
74 if (dev_attr->store)
Yani Ioannou54b6f352005-05-17 06:39:34 -040075 ret = dev_attr->store(dev, dev_attr, buf, count);
Linus Torvalds1da177e2005-04-16 15:20:36 -070076 return ret;
77}
78
79static struct sysfs_ops dev_sysfs_ops = {
80 .show = dev_attr_show,
81 .store = dev_attr_store,
82};
83
84
85/**
86 * device_release - free device structure.
87 * @kobj: device's kobject.
88 *
89 * This is called once the reference count for the object
90 * reaches 0. We forward the call to the device's release
91 * method, which should handle actually freeing the structure.
92 */
93static void device_release(struct kobject * kobj)
94{
95 struct device * dev = to_dev(kobj);
96
97 if (dev->release)
98 dev->release(dev);
Kay Sieversf9f852d2006-10-07 21:54:55 +020099 else if (dev->type && dev->type->release)
100 dev->type->release(dev);
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700101 else if (dev->class && dev->class->dev_release)
102 dev->class->dev_release(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 else {
104 printk(KERN_ERR "Device '%s' does not have a release() function, "
105 "it is broken and must be fixed.\n",
106 dev->bus_id);
107 WARN_ON(1);
108 }
109}
110
Greg Kroah-Hartman8f4afc42007-10-11 10:47:49 -0600111static struct kobj_type device_ktype = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 .release = device_release,
113 .sysfs_ops = &dev_sysfs_ops,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114};
115
116
Kay Sievers312c0042005-11-16 09:00:00 +0100117static int dev_uevent_filter(struct kset *kset, struct kobject *kobj)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118{
119 struct kobj_type *ktype = get_ktype(kobj);
120
Greg Kroah-Hartman8f4afc42007-10-11 10:47:49 -0600121 if (ktype == &device_ktype) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122 struct device *dev = to_dev(kobj);
Cornelia Huck83b5fb4c2007-03-29 11:12:11 +0200123 if (dev->uevent_suppress)
124 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125 if (dev->bus)
126 return 1;
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700127 if (dev->class)
128 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129 }
130 return 0;
131}
132
Kay Sievers312c0042005-11-16 09:00:00 +0100133static const char *dev_uevent_name(struct kset *kset, struct kobject *kobj)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134{
135 struct device *dev = to_dev(kobj);
136
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700137 if (dev->bus)
138 return dev->bus->name;
139 if (dev->class)
140 return dev->class->name;
141 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142}
143
Kay Sievers7eff2e72007-08-14 15:15:12 +0200144static int dev_uevent(struct kset *kset, struct kobject *kobj,
145 struct kobj_uevent_env *env)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146{
147 struct device *dev = to_dev(kobj);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148 int retval = 0;
149
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700150 /* add the major/minor if present */
151 if (MAJOR(dev->devt)) {
Kay Sievers7eff2e72007-08-14 15:15:12 +0200152 add_uevent_var(env, "MAJOR=%u", MAJOR(dev->devt));
153 add_uevent_var(env, "MINOR=%u", MINOR(dev->devt));
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700154 }
155
Kay Sievers414264f2007-03-12 21:08:57 +0100156 if (dev->type && dev->type->name)
Kay Sievers7eff2e72007-08-14 15:15:12 +0200157 add_uevent_var(env, "DEVTYPE=%s", dev->type->name);
Kay Sievers414264f2007-03-12 21:08:57 +0100158
Kay Sievers239378f2006-10-07 21:54:55 +0200159 if (dev->driver)
Kay Sievers7eff2e72007-08-14 15:15:12 +0200160 add_uevent_var(env, "DRIVER=%s", dev->driver->name);
Kay Sievers239378f2006-10-07 21:54:55 +0200161
Kay Sieversa87cb2a2006-09-14 11:23:28 +0200162#ifdef CONFIG_SYSFS_DEPRECATED
Kay Sievers239378f2006-10-07 21:54:55 +0200163 if (dev->class) {
164 struct device *parent = dev->parent;
165
166 /* find first bus device in parent chain */
167 while (parent && !parent->bus)
168 parent = parent->parent;
169 if (parent && parent->bus) {
170 const char *path;
171
172 path = kobject_get_path(&parent->kobj, GFP_KERNEL);
Kay Sievers2c7afd12007-05-01 13:46:26 +0200173 if (path) {
Kay Sievers7eff2e72007-08-14 15:15:12 +0200174 add_uevent_var(env, "PHYSDEVPATH=%s", path);
Kay Sievers2c7afd12007-05-01 13:46:26 +0200175 kfree(path);
176 }
Kay Sievers239378f2006-10-07 21:54:55 +0200177
Kay Sievers7eff2e72007-08-14 15:15:12 +0200178 add_uevent_var(env, "PHYSDEVBUS=%s", parent->bus->name);
Kay Sievers239378f2006-10-07 21:54:55 +0200179
180 if (parent->driver)
Kay Sievers7eff2e72007-08-14 15:15:12 +0200181 add_uevent_var(env, "PHYSDEVDRIVER=%s",
182 parent->driver->name);
Kay Sievers239378f2006-10-07 21:54:55 +0200183 }
184 } else if (dev->bus) {
Kay Sievers7eff2e72007-08-14 15:15:12 +0200185 add_uevent_var(env, "PHYSDEVBUS=%s", dev->bus->name);
Kay Sievers239378f2006-10-07 21:54:55 +0200186
187 if (dev->driver)
Kay Sievers7eff2e72007-08-14 15:15:12 +0200188 add_uevent_var(env, "PHYSDEVDRIVER=%s", dev->driver->name);
Kay Sieversd81d9d62006-08-13 06:17:09 +0200189 }
Kay Sievers239378f2006-10-07 21:54:55 +0200190#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191
Kay Sievers7eff2e72007-08-14 15:15:12 +0200192 /* have the bus specific function add its stuff */
Kay Sievers312c0042005-11-16 09:00:00 +0100193 if (dev->bus && dev->bus->uevent) {
Kay Sievers7eff2e72007-08-14 15:15:12 +0200194 retval = dev->bus->uevent(dev, env);
Kay Sieversf9f852d2006-10-07 21:54:55 +0200195 if (retval)
196 pr_debug ("%s: bus uevent() returned %d\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197 __FUNCTION__, retval);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 }
199
Kay Sievers7eff2e72007-08-14 15:15:12 +0200200 /* have the class specific function add its stuff */
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700201 if (dev->class && dev->class->dev_uevent) {
Kay Sievers7eff2e72007-08-14 15:15:12 +0200202 retval = dev->class->dev_uevent(dev, env);
Kay Sieversf9f852d2006-10-07 21:54:55 +0200203 if (retval)
204 pr_debug("%s: class uevent() returned %d\n",
205 __FUNCTION__, retval);
206 }
207
Kay Sievers7eff2e72007-08-14 15:15:12 +0200208 /* have the device type specific fuction add its stuff */
Kay Sieversf9f852d2006-10-07 21:54:55 +0200209 if (dev->type && dev->type->uevent) {
Kay Sievers7eff2e72007-08-14 15:15:12 +0200210 retval = dev->type->uevent(dev, env);
Kay Sieversf9f852d2006-10-07 21:54:55 +0200211 if (retval)
212 pr_debug("%s: dev_type uevent() returned %d\n",
213 __FUNCTION__, retval);
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700214 }
215
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216 return retval;
217}
218
Kay Sievers312c0042005-11-16 09:00:00 +0100219static struct kset_uevent_ops device_uevent_ops = {
220 .filter = dev_uevent_filter,
221 .name = dev_uevent_name,
222 .uevent = dev_uevent,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223};
224
Kay Sievers16574dc2007-04-06 01:40:38 +0200225static ssize_t show_uevent(struct device *dev, struct device_attribute *attr,
226 char *buf)
227{
228 struct kobject *top_kobj;
229 struct kset *kset;
Kay Sievers7eff2e72007-08-14 15:15:12 +0200230 struct kobj_uevent_env *env = NULL;
Kay Sievers16574dc2007-04-06 01:40:38 +0200231 int i;
232 size_t count = 0;
233 int retval;
234
235 /* search the kset, the device belongs to */
236 top_kobj = &dev->kobj;
Kay Sievers5c5daf62007-08-12 20:43:55 +0200237 while (!top_kobj->kset && top_kobj->parent)
238 top_kobj = top_kobj->parent;
Kay Sievers16574dc2007-04-06 01:40:38 +0200239 if (!top_kobj->kset)
240 goto out;
Kay Sievers5c5daf62007-08-12 20:43:55 +0200241
Kay Sievers16574dc2007-04-06 01:40:38 +0200242 kset = top_kobj->kset;
243 if (!kset->uevent_ops || !kset->uevent_ops->uevent)
244 goto out;
245
246 /* respect filter */
247 if (kset->uevent_ops && kset->uevent_ops->filter)
248 if (!kset->uevent_ops->filter(kset, &dev->kobj))
249 goto out;
250
Kay Sievers7eff2e72007-08-14 15:15:12 +0200251 env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL);
252 if (!env)
Greg Kroah-Hartmanc7308c82007-05-02 14:14:11 +0200253 return -ENOMEM;
254
Kay Sievers16574dc2007-04-06 01:40:38 +0200255 /* let the kset specific function add its keys */
Kay Sievers7eff2e72007-08-14 15:15:12 +0200256 retval = kset->uevent_ops->uevent(kset, &dev->kobj, env);
Kay Sievers16574dc2007-04-06 01:40:38 +0200257 if (retval)
258 goto out;
259
260 /* copy keys to file */
Kay Sievers7eff2e72007-08-14 15:15:12 +0200261 for (i = 0; i < env->envp_idx; i++)
262 count += sprintf(&buf[count], "%s\n", env->envp[i]);
Kay Sievers16574dc2007-04-06 01:40:38 +0200263out:
Kay Sievers7eff2e72007-08-14 15:15:12 +0200264 kfree(env);
Kay Sievers16574dc2007-04-06 01:40:38 +0200265 return count;
266}
267
Kay Sieversa7fd6702005-10-01 14:49:43 +0200268static ssize_t store_uevent(struct device *dev, struct device_attribute *attr,
269 const char *buf, size_t count)
270{
Kay Sievers60a96a52007-07-08 22:29:26 +0200271 enum kobject_action action;
272
Kay Sievers5c5daf62007-08-12 20:43:55 +0200273 if (kobject_action_type(buf, count, &action) == 0) {
Kay Sievers60a96a52007-07-08 22:29:26 +0200274 kobject_uevent(&dev->kobj, action);
275 goto out;
276 }
277
278 dev_err(dev, "uevent: unsupported action-string; this will "
279 "be ignored in a future kernel version\n");
Kay Sievers312c0042005-11-16 09:00:00 +0100280 kobject_uevent(&dev->kobj, KOBJ_ADD);
Kay Sievers60a96a52007-07-08 22:29:26 +0200281out:
Kay Sieversa7fd6702005-10-01 14:49:43 +0200282 return count;
283}
284
Tejun Heoad6a1e12007-06-14 03:45:17 +0900285static struct device_attribute uevent_attr =
286 __ATTR(uevent, S_IRUGO | S_IWUSR, show_uevent, store_uevent);
287
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500288static int device_add_attributes(struct device *dev,
289 struct device_attribute *attrs)
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700290{
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700291 int error = 0;
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500292 int i;
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700293
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500294 if (attrs) {
295 for (i = 0; attr_name(attrs[i]); i++) {
296 error = device_create_file(dev, &attrs[i]);
297 if (error)
298 break;
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700299 }
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500300 if (error)
301 while (--i >= 0)
302 device_remove_file(dev, &attrs[i]);
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700303 }
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700304 return error;
305}
306
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500307static void device_remove_attributes(struct device *dev,
308 struct device_attribute *attrs)
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700309{
310 int i;
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500311
312 if (attrs)
313 for (i = 0; attr_name(attrs[i]); i++)
314 device_remove_file(dev, &attrs[i]);
315}
316
317static int device_add_groups(struct device *dev,
318 struct attribute_group **groups)
319{
320 int error = 0;
321 int i;
322
323 if (groups) {
324 for (i = 0; groups[i]; i++) {
325 error = sysfs_create_group(&dev->kobj, groups[i]);
326 if (error) {
327 while (--i >= 0)
328 sysfs_remove_group(&dev->kobj, groups[i]);
329 break;
330 }
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700331 }
332 }
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500333 return error;
334}
335
336static void device_remove_groups(struct device *dev,
337 struct attribute_group **groups)
338{
339 int i;
340
341 if (groups)
342 for (i = 0; groups[i]; i++)
343 sysfs_remove_group(&dev->kobj, groups[i]);
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700344}
345
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700346static int device_add_attrs(struct device *dev)
347{
348 struct class *class = dev->class;
Kay Sieversf9f852d2006-10-07 21:54:55 +0200349 struct device_type *type = dev->type;
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500350 int error;
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700351
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500352 if (class) {
353 error = device_add_attributes(dev, class->dev_attrs);
Kay Sieversf9f852d2006-10-07 21:54:55 +0200354 if (error)
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500355 return error;
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700356 }
Kay Sieversf9f852d2006-10-07 21:54:55 +0200357
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500358 if (type) {
359 error = device_add_groups(dev, type->groups);
Kay Sieversf9f852d2006-10-07 21:54:55 +0200360 if (error)
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500361 goto err_remove_class_attrs;
Kay Sieversf9f852d2006-10-07 21:54:55 +0200362 }
363
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500364 error = device_add_groups(dev, dev->groups);
365 if (error)
366 goto err_remove_type_groups;
367
368 return 0;
369
370 err_remove_type_groups:
371 if (type)
372 device_remove_groups(dev, type->groups);
373 err_remove_class_attrs:
374 if (class)
375 device_remove_attributes(dev, class->dev_attrs);
376
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700377 return error;
378}
379
380static void device_remove_attrs(struct device *dev)
381{
382 struct class *class = dev->class;
Kay Sieversf9f852d2006-10-07 21:54:55 +0200383 struct device_type *type = dev->type;
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700384
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500385 device_remove_groups(dev, dev->groups);
Kay Sieversf9f852d2006-10-07 21:54:55 +0200386
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500387 if (type)
388 device_remove_groups(dev, type->groups);
389
390 if (class)
391 device_remove_attributes(dev, class->dev_attrs);
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700392}
393
394
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700395static ssize_t show_dev(struct device *dev, struct device_attribute *attr,
396 char *buf)
397{
398 return print_dev_t(buf, dev->devt);
399}
400
Tejun Heoad6a1e12007-06-14 03:45:17 +0900401static struct device_attribute devt_attr =
402 __ATTR(dev, S_IRUGO, show_dev, NULL);
403
Martin Waitz0863afb2006-01-09 20:53:55 -0800404/*
405 * devices_subsys - structure to be registered with kobject core.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700406 */
407
Greg Kroah-Hartman8f4afc42007-10-11 10:47:49 -0600408decl_subsys(devices, &device_ktype, &device_uevent_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409
410
411/**
412 * device_create_file - create sysfs attribute file for device.
413 * @dev: device.
414 * @attr: device attribute descriptor.
415 */
416
417int device_create_file(struct device * dev, struct device_attribute * attr)
418{
419 int error = 0;
420 if (get_device(dev)) {
421 error = sysfs_create_file(&dev->kobj, &attr->attr);
422 put_device(dev);
423 }
424 return error;
425}
426
427/**
428 * device_remove_file - remove sysfs attribute file.
429 * @dev: device.
430 * @attr: device attribute descriptor.
431 */
432
433void device_remove_file(struct device * dev, struct device_attribute * attr)
434{
435 if (get_device(dev)) {
436 sysfs_remove_file(&dev->kobj, &attr->attr);
437 put_device(dev);
438 }
439}
440
Greg Kroah-Hartman2589f1882006-09-19 09:39:19 -0700441/**
442 * device_create_bin_file - create sysfs binary attribute file for device.
443 * @dev: device.
444 * @attr: device binary attribute descriptor.
445 */
446int device_create_bin_file(struct device *dev, struct bin_attribute *attr)
447{
448 int error = -EINVAL;
449 if (dev)
450 error = sysfs_create_bin_file(&dev->kobj, attr);
451 return error;
452}
453EXPORT_SYMBOL_GPL(device_create_bin_file);
454
455/**
456 * device_remove_bin_file - remove sysfs binary attribute file
457 * @dev: device.
458 * @attr: device binary attribute descriptor.
459 */
460void device_remove_bin_file(struct device *dev, struct bin_attribute *attr)
461{
462 if (dev)
463 sysfs_remove_bin_file(&dev->kobj, attr);
464}
465EXPORT_SYMBOL_GPL(device_remove_bin_file);
466
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400467/**
Alan Stern523ded72007-04-26 00:12:04 -0700468 * device_schedule_callback_owner - helper to schedule a callback for a device
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400469 * @dev: device.
470 * @func: callback function to invoke later.
Alan Stern523ded72007-04-26 00:12:04 -0700471 * @owner: module owning the callback routine
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400472 *
473 * Attribute methods must not unregister themselves or their parent device
474 * (which would amount to the same thing). Attempts to do so will deadlock,
475 * since unregistration is mutually exclusive with driver callbacks.
476 *
477 * Instead methods can call this routine, which will attempt to allocate
478 * and schedule a workqueue request to call back @func with @dev as its
479 * argument in the workqueue's process context. @dev will be pinned until
480 * @func returns.
481 *
Alan Stern523ded72007-04-26 00:12:04 -0700482 * This routine is usually called via the inline device_schedule_callback(),
483 * which automatically sets @owner to THIS_MODULE.
484 *
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400485 * Returns 0 if the request was submitted, -ENOMEM if storage could not
Alan Stern523ded72007-04-26 00:12:04 -0700486 * be allocated, -ENODEV if a reference to @owner isn't available.
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400487 *
488 * NOTE: This routine won't work if CONFIG_SYSFS isn't set! It uses an
489 * underlying sysfs routine (since it is intended for use by attribute
490 * methods), and if sysfs isn't available you'll get nothing but -ENOSYS.
491 */
Alan Stern523ded72007-04-26 00:12:04 -0700492int device_schedule_callback_owner(struct device *dev,
493 void (*func)(struct device *), struct module *owner)
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400494{
495 return sysfs_schedule_callback(&dev->kobj,
Alan Stern523ded72007-04-26 00:12:04 -0700496 (void (*)(void *)) func, dev, owner);
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400497}
Alan Stern523ded72007-04-26 00:12:04 -0700498EXPORT_SYMBOL_GPL(device_schedule_callback_owner);
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400499
James Bottomley34bb61f2005-09-06 16:56:51 -0700500static void klist_children_get(struct klist_node *n)
501{
502 struct device *dev = container_of(n, struct device, knode_parent);
503
504 get_device(dev);
505}
506
507static void klist_children_put(struct klist_node *n)
508{
509 struct device *dev = container_of(n, struct device, knode_parent);
510
511 put_device(dev);
512}
513
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514
515/**
516 * device_initialize - init device structure.
517 * @dev: device.
518 *
519 * This prepares the device for use by other layers,
520 * including adding it to the device hierarchy.
521 * It is the first half of device_register(), if called by
522 * that, though it can also be called separately, so one
523 * may use @dev's fields (e.g. the refcount).
524 */
525
526void device_initialize(struct device *dev)
527{
528 kobj_set_kset_s(dev, devices_subsys);
529 kobject_init(&dev->kobj);
James Bottomley34bb61f2005-09-06 16:56:51 -0700530 klist_init(&dev->klist_children, klist_children_get,
531 klist_children_put);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532 INIT_LIST_HEAD(&dev->dma_pools);
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700533 INIT_LIST_HEAD(&dev->node);
mochel@digitalimplant.orgaf703162005-03-21 10:41:04 -0800534 init_MUTEX(&dev->sem);
Tejun Heo9ac78492007-01-20 16:00:26 +0900535 spin_lock_init(&dev->devres_lock);
536 INIT_LIST_HEAD(&dev->devres_head);
David Brownell0ac85242005-09-12 19:39:34 -0700537 device_init_wakeup(dev, 0);
Christoph Hellwig87348132006-12-06 20:32:33 -0800538 set_dev_node(dev, -1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539}
540
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100541#ifdef CONFIG_SYSFS_DEPRECATED
Cornelia Huckc744aea2007-01-08 20:16:44 +0100542static struct kobject * get_device_parent(struct device *dev,
543 struct device *parent)
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100544{
Dmitry Torokhov3eb215d2007-10-07 12:22:21 -0400545 /*
546 * Set the parent to the class, not the parent device
547 * for topmost devices in class hierarchy.
548 * This keeps sysfs from having a symlink to make old
549 * udevs happy
550 */
551 if (dev->class && (!parent || parent->class != dev->class))
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700552 return &dev->class->subsys.kobj;
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100553 else if (parent)
Cornelia Huckc744aea2007-01-08 20:16:44 +0100554 return &parent->kobj;
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100555
Cornelia Huckc744aea2007-01-08 20:16:44 +0100556 return NULL;
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100557}
558#else
Kay Sievers86406242007-03-14 03:25:56 +0100559static struct kobject *virtual_device_parent(struct device *dev)
Greg Kroah-Hartmanf0ee61a2006-10-23 10:40:54 -0700560{
Kay Sievers86406242007-03-14 03:25:56 +0100561 static struct kobject *virtual_dir = NULL;
Greg Kroah-Hartmanf0ee61a2006-10-23 10:40:54 -0700562
Kay Sievers86406242007-03-14 03:25:56 +0100563 if (!virtual_dir)
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700564 virtual_dir = kobject_add_dir(&devices_subsys.kobj, "virtual");
Greg Kroah-Hartmanf0ee61a2006-10-23 10:40:54 -0700565
Kay Sievers86406242007-03-14 03:25:56 +0100566 return virtual_dir;
Greg Kroah-Hartmanf0ee61a2006-10-23 10:40:54 -0700567}
568
Cornelia Huckc744aea2007-01-08 20:16:44 +0100569static struct kobject * get_device_parent(struct device *dev,
570 struct device *parent)
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100571{
Kay Sievers86406242007-03-14 03:25:56 +0100572 if (dev->class) {
573 struct kobject *kobj = NULL;
574 struct kobject *parent_kobj;
575 struct kobject *k;
576
577 /*
578 * If we have no parent, we live in "virtual".
579 * Class-devices with a bus-device as parent, live
580 * in a class-directory to prevent namespace collisions.
581 */
582 if (parent == NULL)
583 parent_kobj = virtual_device_parent(dev);
584 else if (parent->class)
585 return &parent->kobj;
586 else
587 parent_kobj = &parent->kobj;
588
589 /* find our class-directory at the parent and reference it */
590 spin_lock(&dev->class->class_dirs.list_lock);
591 list_for_each_entry(k, &dev->class->class_dirs.list, entry)
592 if (k->parent == parent_kobj) {
593 kobj = kobject_get(k);
594 break;
595 }
596 spin_unlock(&dev->class->class_dirs.list_lock);
597 if (kobj)
598 return kobj;
599
600 /* or create a new class-directory at the parent device */
601 return kobject_kset_add_dir(&dev->class->class_dirs,
602 parent_kobj, dev->class->name);
603 }
604
605 if (parent)
Cornelia Huckc744aea2007-01-08 20:16:44 +0100606 return &parent->kobj;
607 return NULL;
608}
Cornelia Huckc744aea2007-01-08 20:16:44 +0100609#endif
Kay Sievers86406242007-03-14 03:25:56 +0100610
Cornelia Huckc744aea2007-01-08 20:16:44 +0100611static int setup_parent(struct device *dev, struct device *parent)
612{
613 struct kobject *kobj;
614 kobj = get_device_parent(dev, parent);
615 if (IS_ERR(kobj))
616 return PTR_ERR(kobj);
617 if (kobj)
618 dev->kobj.parent = kobj;
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100619 return 0;
620}
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100621
Cornelia Huck2ee97caf2007-07-18 01:43:47 -0700622static int device_add_class_symlinks(struct device *dev)
623{
624 int error;
625
626 if (!dev->class)
627 return 0;
628 error = sysfs_create_link(&dev->kobj, &dev->class->subsys.kobj,
629 "subsystem");
630 if (error)
631 goto out;
632 /*
633 * If this is not a "fake" compatible device, then create the
634 * symlink from the class to the device.
635 */
636 if (dev->kobj.parent != &dev->class->subsys.kobj) {
637 error = sysfs_create_link(&dev->class->subsys.kobj, &dev->kobj,
638 dev->bus_id);
639 if (error)
640 goto out_subsys;
641 }
Cornelia Huck27907682007-07-25 09:58:08 +0200642 if (dev->parent) {
Cornelia Huck2ee97caf2007-07-18 01:43:47 -0700643#ifdef CONFIG_SYSFS_DEPRECATED
644 {
Dmitry Torokhov4f01a752007-09-18 22:46:50 -0700645 struct device *parent = dev->parent;
646 char *class_name;
647
648 /*
649 * In old sysfs stacked class devices had 'device'
650 * link pointing to real device instead of parent
651 */
652 while (parent->class && !parent->bus && parent->parent)
653 parent = parent->parent;
654
655 error = sysfs_create_link(&dev->kobj,
656 &parent->kobj,
657 "device");
658 if (error)
659 goto out_busid;
660
661 class_name = make_class_name(dev->class->name,
662 &dev->kobj);
Cornelia Huck2ee97caf2007-07-18 01:43:47 -0700663 if (class_name)
664 error = sysfs_create_link(&dev->parent->kobj,
665 &dev->kobj, class_name);
666 kfree(class_name);
667 if (error)
668 goto out_device;
669 }
Dmitry Torokhov4f01a752007-09-18 22:46:50 -0700670#else
671 error = sysfs_create_link(&dev->kobj, &dev->parent->kobj,
672 "device");
673 if (error)
674 goto out_busid;
Cornelia Huck2ee97caf2007-07-18 01:43:47 -0700675#endif
676 }
677 return 0;
678
679#ifdef CONFIG_SYSFS_DEPRECATED
680out_device:
681 if (dev->parent)
682 sysfs_remove_link(&dev->kobj, "device");
683#endif
684out_busid:
685 if (dev->kobj.parent != &dev->class->subsys.kobj)
686 sysfs_remove_link(&dev->class->subsys.kobj, dev->bus_id);
687out_subsys:
688 sysfs_remove_link(&dev->kobj, "subsystem");
689out:
690 return error;
691}
692
693static void device_remove_class_symlinks(struct device *dev)
694{
695 if (!dev->class)
696 return;
697 if (dev->parent) {
698#ifdef CONFIG_SYSFS_DEPRECATED
699 char *class_name;
700
701 class_name = make_class_name(dev->class->name, &dev->kobj);
702 if (class_name) {
703 sysfs_remove_link(&dev->parent->kobj, class_name);
704 kfree(class_name);
705 }
706#endif
707 sysfs_remove_link(&dev->kobj, "device");
708 }
709 if (dev->kobj.parent != &dev->class->subsys.kobj)
710 sysfs_remove_link(&dev->class->subsys.kobj, dev->bus_id);
711 sysfs_remove_link(&dev->kobj, "subsystem");
712}
713
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714/**
715 * device_add - add device to device hierarchy.
716 * @dev: device.
717 *
718 * This is part 2 of device_register(), though may be called
719 * separately _iff_ device_initialize() has been called separately.
720 *
721 * This adds it to the kobject hierarchy via kobject_add(), adds it
722 * to the global and sibling lists for the device, then
723 * adds it to the other relevant subsystems of the driver model.
724 */
725int device_add(struct device *dev)
726{
727 struct device *parent = NULL;
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200728 struct class_interface *class_intf;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729 int error = -EINVAL;
730
731 dev = get_device(dev);
732 if (!dev || !strlen(dev->bus_id))
733 goto Error;
734
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100735 pr_debug("DEV: registering device: ID = '%s'\n", dev->bus_id);
Greg Kroah-Hartmanc205ef42006-08-07 22:19:37 -0700736
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737 parent = get_device(dev->parent);
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100738 error = setup_parent(dev, parent);
739 if (error)
740 goto Error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741
742 /* first, register with generic layer. */
743 kobject_set_name(&dev->kobj, "%s", dev->bus_id);
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100744 error = kobject_add(&dev->kobj);
745 if (error)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746 goto Error;
Kay Sieversa7fd6702005-10-01 14:49:43 +0200747
Brian Walsh37022642006-08-14 22:43:19 -0700748 /* notify platform of device entry */
749 if (platform_notify)
750 platform_notify(dev);
751
Benjamin Herrenschmidt116af372006-10-25 13:44:59 +1000752 /* notify clients of device entry (new way) */
753 if (dev->bus)
754 blocking_notifier_call_chain(&dev->bus->bus_notifier,
755 BUS_NOTIFY_ADD_DEVICE, dev);
756
Tejun Heoad6a1e12007-06-14 03:45:17 +0900757 error = device_create_file(dev, &uevent_attr);
Cornelia Hucka306eea2006-09-22 11:37:13 +0200758 if (error)
759 goto attrError;
Kay Sieversa7fd6702005-10-01 14:49:43 +0200760
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700761 if (MAJOR(dev->devt)) {
Tejun Heoad6a1e12007-06-14 03:45:17 +0900762 error = device_create_file(dev, &devt_attr);
763 if (error)
Cornelia Hucka306eea2006-09-22 11:37:13 +0200764 goto ueventattrError;
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700765 }
766
Cornelia Huck2ee97caf2007-07-18 01:43:47 -0700767 error = device_add_class_symlinks(dev);
768 if (error)
769 goto SymlinkError;
Cornelia Huckdc0afa82007-07-09 11:39:18 -0700770 error = device_add_attrs(dev);
771 if (error)
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700772 goto AttrsError;
Cornelia Huckdc0afa82007-07-09 11:39:18 -0700773 error = device_pm_add(dev);
774 if (error)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775 goto PMError;
Cornelia Huckdc0afa82007-07-09 11:39:18 -0700776 error = bus_add_device(dev);
777 if (error)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778 goto BusError;
Cornelia Huck83b5fb4c2007-03-29 11:12:11 +0200779 kobject_uevent(&dev->kobj, KOBJ_ADD);
Cornelia Huckc6a46692007-02-05 16:15:26 -0800780 bus_attach_device(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781 if (parent)
James Bottomleyd856f1e2005-08-19 09:14:01 -0400782 klist_add_tail(&dev->knode_parent, &parent->klist_children);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700783
Greg Kroah-Hartman5d9fd162006-06-22 17:17:32 -0700784 if (dev->class) {
Greg Kroah-Hartman5d9fd162006-06-22 17:17:32 -0700785 down(&dev->class->sem);
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200786 /* tie the class to the device */
Greg Kroah-Hartman5d9fd162006-06-22 17:17:32 -0700787 list_add_tail(&dev->node, &dev->class->devices);
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200788
789 /* notify any interfaces that the device is here */
790 list_for_each_entry(class_intf, &dev->class->interfaces, node)
791 if (class_intf->add_dev)
792 class_intf->add_dev(dev, class_intf);
Greg Kroah-Hartman5d9fd162006-06-22 17:17:32 -0700793 up(&dev->class->sem);
794 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795 Done:
796 put_device(dev);
797 return error;
798 BusError:
799 device_pm_remove(dev);
800 PMError:
Benjamin Herrenschmidt116af372006-10-25 13:44:59 +1000801 if (dev->bus)
802 blocking_notifier_call_chain(&dev->bus->bus_notifier,
803 BUS_NOTIFY_DEL_DEVICE, dev);
James Simmons82f0cf92007-02-21 17:44:51 +0000804 device_remove_attrs(dev);
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700805 AttrsError:
Cornelia Huck2ee97caf2007-07-18 01:43:47 -0700806 device_remove_class_symlinks(dev);
807 SymlinkError:
Tejun Heoad6a1e12007-06-14 03:45:17 +0900808 if (MAJOR(dev->devt))
809 device_remove_file(dev, &devt_attr);
James Simmons82f0cf92007-02-21 17:44:51 +0000810
811 if (dev->class) {
812 sysfs_remove_link(&dev->kobj, "subsystem");
813 /* If this is not a "fake" compatible device, remove the
814 * symlink from the class to the device. */
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700815 if (dev->kobj.parent != &dev->class->subsys.kobj)
816 sysfs_remove_link(&dev->class->subsys.kobj,
James Simmons82f0cf92007-02-21 17:44:51 +0000817 dev->bus_id);
James Simmons82f0cf92007-02-21 17:44:51 +0000818 if (parent) {
Greg Kroah-Hartmanf7f34612007-03-06 12:55:53 -0800819#ifdef CONFIG_SYSFS_DEPRECATED
James Simmons82f0cf92007-02-21 17:44:51 +0000820 char *class_name = make_class_name(dev->class->name,
821 &dev->kobj);
822 if (class_name)
823 sysfs_remove_link(&dev->parent->kobj,
824 class_name);
825 kfree(class_name);
Greg Kroah-Hartmanf7f34612007-03-06 12:55:53 -0800826#endif
James Simmons82f0cf92007-02-21 17:44:51 +0000827 sysfs_remove_link(&dev->kobj, "device");
828 }
James Simmons82f0cf92007-02-21 17:44:51 +0000829 }
Cornelia Hucka306eea2006-09-22 11:37:13 +0200830 ueventattrError:
Tejun Heoad6a1e12007-06-14 03:45:17 +0900831 device_remove_file(dev, &uevent_attr);
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700832 attrError:
Kay Sievers312c0042005-11-16 09:00:00 +0100833 kobject_uevent(&dev->kobj, KOBJ_REMOVE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834 kobject_del(&dev->kobj);
835 Error:
836 if (parent)
837 put_device(parent);
838 goto Done;
839}
840
841
842/**
843 * device_register - register a device with the system.
844 * @dev: pointer to the device structure
845 *
846 * This happens in two clean steps - initialize the device
847 * and add it to the system. The two steps can be called
848 * separately, but this is the easiest and most common.
849 * I.e. you should only call the two helpers separately if
850 * have a clearly defined need to use and refcount the device
851 * before it is added to the hierarchy.
852 */
853
854int device_register(struct device *dev)
855{
856 device_initialize(dev);
857 return device_add(dev);
858}
859
860
861/**
862 * get_device - increment reference count for device.
863 * @dev: device.
864 *
865 * This simply forwards the call to kobject_get(), though
866 * we do take care to provide for the case that we get a NULL
867 * pointer passed in.
868 */
869
870struct device * get_device(struct device * dev)
871{
872 return dev ? to_dev(kobject_get(&dev->kobj)) : NULL;
873}
874
875
876/**
877 * put_device - decrement reference count.
878 * @dev: device in question.
879 */
880void put_device(struct device * dev)
881{
882 if (dev)
883 kobject_put(&dev->kobj);
884}
885
886
887/**
888 * device_del - delete device from system.
889 * @dev: device.
890 *
891 * This is the first part of the device unregistration
892 * sequence. This removes the device from the lists we control
893 * from here, has it removed from the other driver model
894 * subsystems it was added to in device_add(), and removes it
895 * from the kobject hierarchy.
896 *
897 * NOTE: this should be called manually _iff_ device_add() was
898 * also called manually.
899 */
900
901void device_del(struct device * dev)
902{
903 struct device * parent = dev->parent;
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200904 struct class_interface *class_intf;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905
Linus Torvalds1da177e2005-04-16 15:20:36 -0700906 if (parent)
Patrick Mocheld62c0f92005-06-24 08:39:33 -0700907 klist_del(&dev->knode_parent);
Tejun Heoad6a1e12007-06-14 03:45:17 +0900908 if (MAJOR(dev->devt))
909 device_remove_file(dev, &devt_attr);
Kay Sieversb9d9c822006-06-15 15:31:56 +0200910 if (dev->class) {
911 sysfs_remove_link(&dev->kobj, "subsystem");
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100912 /* If this is not a "fake" compatible device, remove the
913 * symlink from the class to the device. */
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700914 if (dev->kobj.parent != &dev->class->subsys.kobj)
915 sysfs_remove_link(&dev->class->subsys.kobj,
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100916 dev->bus_id);
Greg Kroah-Hartman64bb5d22006-06-28 16:19:58 -0700917 if (parent) {
Greg Kroah-Hartmanf7f34612007-03-06 12:55:53 -0800918#ifdef CONFIG_SYSFS_DEPRECATED
Kay Sievers99ef3ef2006-09-14 11:23:28 +0200919 char *class_name = make_class_name(dev->class->name,
920 &dev->kobj);
Cornelia Huckcb360bb2006-11-27 10:35:05 +0100921 if (class_name)
922 sysfs_remove_link(&dev->parent->kobj,
923 class_name);
Kay Sievers99ef3ef2006-09-14 11:23:28 +0200924 kfree(class_name);
Greg Kroah-Hartmanf7f34612007-03-06 12:55:53 -0800925#endif
Kay Sievers99ef3ef2006-09-14 11:23:28 +0200926 sysfs_remove_link(&dev->kobj, "device");
Greg Kroah-Hartman64bb5d22006-06-28 16:19:58 -0700927 }
Kay Sievers99ef3ef2006-09-14 11:23:28 +0200928
Greg Kroah-Hartman5d9fd162006-06-22 17:17:32 -0700929 down(&dev->class->sem);
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200930 /* notify any interfaces that the device is now gone */
931 list_for_each_entry(class_intf, &dev->class->interfaces, node)
932 if (class_intf->remove_dev)
933 class_intf->remove_dev(dev, class_intf);
934 /* remove the device from the class list */
Greg Kroah-Hartman5d9fd162006-06-22 17:17:32 -0700935 list_del_init(&dev->node);
936 up(&dev->class->sem);
Kay Sievers86406242007-03-14 03:25:56 +0100937
938 /* If we live in a parent class-directory, unreference it */
939 if (dev->kobj.parent->kset == &dev->class->class_dirs) {
940 struct device *d;
941 int other = 0;
942
943 /*
944 * if we are the last child of our class, delete
945 * our class-directory at this parent
946 */
947 down(&dev->class->sem);
948 list_for_each_entry(d, &dev->class->devices, node) {
949 if (d == dev)
950 continue;
951 if (d->kobj.parent == dev->kobj.parent) {
952 other = 1;
953 break;
954 }
955 }
956 if (!other)
957 kobject_del(dev->kobj.parent);
958
959 kobject_put(dev->kobj.parent);
960 up(&dev->class->sem);
961 }
Kay Sieversb9d9c822006-06-15 15:31:56 +0200962 }
Tejun Heoad6a1e12007-06-14 03:45:17 +0900963 device_remove_file(dev, &uevent_attr);
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700964 device_remove_attrs(dev);
Benjamin Herrenschmidt28953532006-11-08 19:46:14 -0800965 bus_remove_device(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700966
Tejun Heo2f8d16a2007-03-09 19:34:19 +0900967 /*
968 * Some platform devices are driven without driver attached
969 * and managed resources may have been acquired. Make sure
970 * all resources are released.
971 */
972 devres_release_all(dev);
973
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974 /* Notify the platform of the removal, in case they
975 * need to do anything...
976 */
977 if (platform_notify_remove)
978 platform_notify_remove(dev);
Benjamin Herrenschmidt116af372006-10-25 13:44:59 +1000979 if (dev->bus)
980 blocking_notifier_call_chain(&dev->bus->bus_notifier,
981 BUS_NOTIFY_DEL_DEVICE, dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700982 device_pm_remove(dev);
Kay Sievers312c0042005-11-16 09:00:00 +0100983 kobject_uevent(&dev->kobj, KOBJ_REMOVE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700984 kobject_del(&dev->kobj);
985 if (parent)
986 put_device(parent);
987}
988
989/**
990 * device_unregister - unregister device from system.
991 * @dev: device going away.
992 *
993 * We do this in two parts, like we do device_register(). First,
994 * we remove it from all the subsystems with device_del(), then
995 * we decrement the reference count via put_device(). If that
996 * is the final reference count, the device will be cleaned up
997 * via device_release() above. Otherwise, the structure will
998 * stick around until the final reference to the device is dropped.
999 */
1000void device_unregister(struct device * dev)
1001{
1002 pr_debug("DEV: Unregistering device. ID = '%s'\n", dev->bus_id);
1003 device_del(dev);
1004 put_device(dev);
1005}
1006
1007
mochel@digitalimplant.org36239572005-03-24 19:08:30 -08001008static struct device * next_device(struct klist_iter * i)
1009{
1010 struct klist_node * n = klist_next(i);
1011 return n ? container_of(n, struct device, knode_parent) : NULL;
1012}
1013
Linus Torvalds1da177e2005-04-16 15:20:36 -07001014/**
1015 * device_for_each_child - device child iterator.
Randy Dunlapc41455f2005-10-23 11:59:14 -07001016 * @parent: parent struct device.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001017 * @data: data for the callback.
1018 * @fn: function to be called for each device.
1019 *
Randy Dunlapc41455f2005-10-23 11:59:14 -07001020 * Iterate over @parent's child devices, and call @fn for each,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001021 * passing it @data.
1022 *
1023 * We check the return of @fn each time. If it returns anything
1024 * other than 0, we break out and return that value.
1025 */
mochel@digitalimplant.org36239572005-03-24 19:08:30 -08001026int device_for_each_child(struct device * parent, void * data,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001027 int (*fn)(struct device *, void *))
1028{
mochel@digitalimplant.org36239572005-03-24 19:08:30 -08001029 struct klist_iter i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001030 struct device * child;
1031 int error = 0;
1032
mochel@digitalimplant.org36239572005-03-24 19:08:30 -08001033 klist_iter_init(&parent->klist_children, &i);
1034 while ((child = next_device(&i)) && !error)
1035 error = fn(child, data);
1036 klist_iter_exit(&i);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001037 return error;
1038}
1039
Cornelia Huck5ab69982006-11-16 15:42:07 +01001040/**
1041 * device_find_child - device iterator for locating a particular device.
1042 * @parent: parent struct device
1043 * @data: Data to pass to match function
1044 * @match: Callback function to check device
1045 *
1046 * This is similar to the device_for_each_child() function above, but it
1047 * returns a reference to a device that is 'found' for later use, as
1048 * determined by the @match callback.
1049 *
1050 * The callback should return 0 if the device doesn't match and non-zero
1051 * if it does. If the callback returns non-zero and a reference to the
1052 * current device can be obtained, this function will return to the caller
1053 * and not iterate over any more devices.
1054 */
1055struct device * device_find_child(struct device *parent, void *data,
1056 int (*match)(struct device *, void *))
1057{
1058 struct klist_iter i;
1059 struct device *child;
1060
1061 if (!parent)
1062 return NULL;
1063
1064 klist_iter_init(&parent->klist_children, &i);
1065 while ((child = next_device(&i)))
1066 if (match(child, data) && get_device(child))
1067 break;
1068 klist_iter_exit(&i);
1069 return child;
1070}
1071
Linus Torvalds1da177e2005-04-16 15:20:36 -07001072int __init devices_init(void)
1073{
1074 return subsystem_register(&devices_subsys);
1075}
1076
1077EXPORT_SYMBOL_GPL(device_for_each_child);
Cornelia Huck5ab69982006-11-16 15:42:07 +01001078EXPORT_SYMBOL_GPL(device_find_child);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001079
1080EXPORT_SYMBOL_GPL(device_initialize);
1081EXPORT_SYMBOL_GPL(device_add);
1082EXPORT_SYMBOL_GPL(device_register);
1083
1084EXPORT_SYMBOL_GPL(device_del);
1085EXPORT_SYMBOL_GPL(device_unregister);
1086EXPORT_SYMBOL_GPL(get_device);
1087EXPORT_SYMBOL_GPL(put_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001088
1089EXPORT_SYMBOL_GPL(device_create_file);
1090EXPORT_SYMBOL_GPL(device_remove_file);
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001091
1092
1093static void device_create_release(struct device *dev)
1094{
1095 pr_debug("%s called for %s\n", __FUNCTION__, dev->bus_id);
1096 kfree(dev);
1097}
1098
1099/**
1100 * device_create - creates a device and registers it with sysfs
Henrik Kretzschmar42734da2006-07-05 00:53:19 +02001101 * @class: pointer to the struct class that this device should be registered to
1102 * @parent: pointer to the parent struct device of this new device, if any
1103 * @devt: the dev_t for the char device to be added
1104 * @fmt: string for the device's name
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001105 *
Henrik Kretzschmar42734da2006-07-05 00:53:19 +02001106 * This function can be used by char device classes. A struct device
1107 * will be created in sysfs, registered to the specified class.
1108 *
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001109 * A "dev" file will be created, showing the dev_t for the device, if
1110 * the dev_t is not 0,0.
Henrik Kretzschmar42734da2006-07-05 00:53:19 +02001111 * If a pointer to a parent struct device is passed in, the newly created
1112 * struct device will be a child of that device in sysfs.
1113 * The pointer to the struct device will be returned from the call.
1114 * Any further sysfs files that might be required can be created using this
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001115 * pointer.
1116 *
1117 * Note: the struct class passed to this function must have previously
1118 * been created with a call to class_create().
1119 */
1120struct device *device_create(struct class *class, struct device *parent,
Greg Kroah-Hartman5cbe5f82006-08-10 01:19:19 -04001121 dev_t devt, const char *fmt, ...)
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001122{
1123 va_list args;
1124 struct device *dev = NULL;
1125 int retval = -ENODEV;
1126
1127 if (class == NULL || IS_ERR(class))
1128 goto error;
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001129
1130 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1131 if (!dev) {
1132 retval = -ENOMEM;
1133 goto error;
1134 }
1135
1136 dev->devt = devt;
1137 dev->class = class;
1138 dev->parent = parent;
1139 dev->release = device_create_release;
1140
1141 va_start(args, fmt);
1142 vsnprintf(dev->bus_id, BUS_ID_SIZE, fmt, args);
1143 va_end(args);
1144 retval = device_register(dev);
1145 if (retval)
1146 goto error;
1147
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001148 return dev;
1149
1150error:
1151 kfree(dev);
1152 return ERR_PTR(retval);
1153}
1154EXPORT_SYMBOL_GPL(device_create);
1155
1156/**
1157 * device_destroy - removes a device that was created with device_create()
Henrik Kretzschmar42734da2006-07-05 00:53:19 +02001158 * @class: pointer to the struct class that this device was registered with
1159 * @devt: the dev_t of the device that was previously registered
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001160 *
Henrik Kretzschmar42734da2006-07-05 00:53:19 +02001161 * This call unregisters and cleans up a device that was created with a
1162 * call to device_create().
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001163 */
1164void device_destroy(struct class *class, dev_t devt)
1165{
1166 struct device *dev = NULL;
1167 struct device *dev_tmp;
1168
1169 down(&class->sem);
1170 list_for_each_entry(dev_tmp, &class->devices, node) {
1171 if (dev_tmp->devt == devt) {
1172 dev = dev_tmp;
1173 break;
1174 }
1175 }
1176 up(&class->sem);
1177
Greg Kroah-Hartman5d9fd162006-06-22 17:17:32 -07001178 if (dev)
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001179 device_unregister(dev);
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001180}
1181EXPORT_SYMBOL_GPL(device_destroy);
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001182
1183/**
1184 * device_rename - renames a device
1185 * @dev: the pointer to the struct device to be renamed
1186 * @new_name: the new name of the device
1187 */
1188int device_rename(struct device *dev, char *new_name)
1189{
1190 char *old_class_name = NULL;
1191 char *new_class_name = NULL;
Cornelia Huck2ee97caf2007-07-18 01:43:47 -07001192 char *old_device_name = NULL;
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001193 int error;
1194
1195 dev = get_device(dev);
1196 if (!dev)
1197 return -EINVAL;
1198
1199 pr_debug("DEVICE: renaming '%s' to '%s'\n", dev->bus_id, new_name);
1200
Kay Sievers99ef3ef2006-09-14 11:23:28 +02001201#ifdef CONFIG_SYSFS_DEPRECATED
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001202 if ((dev->class) && (dev->parent))
1203 old_class_name = make_class_name(dev->class->name, &dev->kobj);
Kay Sievers99ef3ef2006-09-14 11:23:28 +02001204#endif
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001205
Cornelia Huck2ee97caf2007-07-18 01:43:47 -07001206 old_device_name = kmalloc(BUS_ID_SIZE, GFP_KERNEL);
1207 if (!old_device_name) {
1208 error = -ENOMEM;
1209 goto out;
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001210 }
Cornelia Huck2ee97caf2007-07-18 01:43:47 -07001211 strlcpy(old_device_name, dev->bus_id, BUS_ID_SIZE);
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001212 strlcpy(dev->bus_id, new_name, BUS_ID_SIZE);
1213
1214 error = kobject_rename(&dev->kobj, new_name);
Cornelia Huck2ee97caf2007-07-18 01:43:47 -07001215 if (error) {
1216 strlcpy(dev->bus_id, old_device_name, BUS_ID_SIZE);
1217 goto out;
1218 }
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001219
Kay Sievers99ef3ef2006-09-14 11:23:28 +02001220#ifdef CONFIG_SYSFS_DEPRECATED
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001221 if (old_class_name) {
1222 new_class_name = make_class_name(dev->class->name, &dev->kobj);
1223 if (new_class_name) {
Cornelia Huck2ee97caf2007-07-18 01:43:47 -07001224 error = sysfs_create_link(&dev->parent->kobj,
1225 &dev->kobj, new_class_name);
1226 if (error)
1227 goto out;
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001228 sysfs_remove_link(&dev->parent->kobj, old_class_name);
1229 }
1230 }
Kay Sievers99ef3ef2006-09-14 11:23:28 +02001231#endif
1232
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001233 if (dev->class) {
Cornelia Huck2ee97caf2007-07-18 01:43:47 -07001234 sysfs_remove_link(&dev->class->subsys.kobj, old_device_name);
1235 error = sysfs_create_link(&dev->class->subsys.kobj, &dev->kobj,
1236 dev->bus_id);
1237 if (error) {
1238 /* Uh... how to unravel this if restoring can fail? */
1239 dev_err(dev, "%s: sysfs_create_symlink failed (%d)\n",
1240 __FUNCTION__, error);
1241 }
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001242 }
Cornelia Huck2ee97caf2007-07-18 01:43:47 -07001243out:
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001244 put_device(dev);
1245
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001246 kfree(new_class_name);
Jesper Juhl952ab432006-09-28 23:56:01 +02001247 kfree(old_class_name);
Cornelia Huck2ee97caf2007-07-18 01:43:47 -07001248 kfree(old_device_name);
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001249
1250 return error;
1251}
Johannes Berga2807db2007-02-28 12:38:31 +01001252EXPORT_SYMBOL_GPL(device_rename);
Cornelia Huck8a824722006-11-20 17:07:51 +01001253
1254static int device_move_class_links(struct device *dev,
1255 struct device *old_parent,
1256 struct device *new_parent)
1257{
Greg Kroah-Hartmanf7f34612007-03-06 12:55:53 -08001258 int error = 0;
Cornelia Huck8a824722006-11-20 17:07:51 +01001259#ifdef CONFIG_SYSFS_DEPRECATED
Cornelia Huck8a824722006-11-20 17:07:51 +01001260 char *class_name;
1261
1262 class_name = make_class_name(dev->class->name, &dev->kobj);
1263 if (!class_name) {
Cornelia Huckcb360bb2006-11-27 10:35:05 +01001264 error = -ENOMEM;
Cornelia Huck8a824722006-11-20 17:07:51 +01001265 goto out;
1266 }
1267 if (old_parent) {
1268 sysfs_remove_link(&dev->kobj, "device");
1269 sysfs_remove_link(&old_parent->kobj, class_name);
1270 }
Cornelia Huckc744aea2007-01-08 20:16:44 +01001271 if (new_parent) {
1272 error = sysfs_create_link(&dev->kobj, &new_parent->kobj,
1273 "device");
1274 if (error)
1275 goto out;
1276 error = sysfs_create_link(&new_parent->kobj, &dev->kobj,
1277 class_name);
1278 if (error)
1279 sysfs_remove_link(&dev->kobj, "device");
1280 }
1281 else
1282 error = 0;
Cornelia Huck8a824722006-11-20 17:07:51 +01001283out:
1284 kfree(class_name);
1285 return error;
1286#else
Greg Kroah-Hartmanf7f34612007-03-06 12:55:53 -08001287 if (old_parent)
1288 sysfs_remove_link(&dev->kobj, "device");
1289 if (new_parent)
1290 error = sysfs_create_link(&dev->kobj, &new_parent->kobj,
1291 "device");
1292 return error;
Cornelia Huck8a824722006-11-20 17:07:51 +01001293#endif
1294}
1295
1296/**
1297 * device_move - moves a device to a new parent
1298 * @dev: the pointer to the struct device to be moved
Cornelia Huckc744aea2007-01-08 20:16:44 +01001299 * @new_parent: the new parent of the device (can by NULL)
Cornelia Huck8a824722006-11-20 17:07:51 +01001300 */
1301int device_move(struct device *dev, struct device *new_parent)
1302{
1303 int error;
1304 struct device *old_parent;
Cornelia Huckc744aea2007-01-08 20:16:44 +01001305 struct kobject *new_parent_kobj;
Cornelia Huck8a824722006-11-20 17:07:51 +01001306
1307 dev = get_device(dev);
1308 if (!dev)
1309 return -EINVAL;
1310
Cornelia Huck8a824722006-11-20 17:07:51 +01001311 new_parent = get_device(new_parent);
Cornelia Huckc744aea2007-01-08 20:16:44 +01001312 new_parent_kobj = get_device_parent (dev, new_parent);
1313 if (IS_ERR(new_parent_kobj)) {
1314 error = PTR_ERR(new_parent_kobj);
1315 put_device(new_parent);
Cornelia Huck8a824722006-11-20 17:07:51 +01001316 goto out;
1317 }
1318 pr_debug("DEVICE: moving '%s' to '%s'\n", dev->bus_id,
Cornelia Huckc744aea2007-01-08 20:16:44 +01001319 new_parent ? new_parent->bus_id : "<NULL>");
1320 error = kobject_move(&dev->kobj, new_parent_kobj);
Cornelia Huck8a824722006-11-20 17:07:51 +01001321 if (error) {
1322 put_device(new_parent);
1323 goto out;
1324 }
1325 old_parent = dev->parent;
1326 dev->parent = new_parent;
1327 if (old_parent)
Cornelia Huckacf02d22006-11-22 17:49:39 +01001328 klist_remove(&dev->knode_parent);
Cornelia Huckc744aea2007-01-08 20:16:44 +01001329 if (new_parent)
1330 klist_add_tail(&dev->knode_parent, &new_parent->klist_children);
Cornelia Huck8a824722006-11-20 17:07:51 +01001331 if (!dev->class)
1332 goto out_put;
1333 error = device_move_class_links(dev, old_parent, new_parent);
1334 if (error) {
1335 /* We ignore errors on cleanup since we're hosed anyway... */
1336 device_move_class_links(dev, new_parent, old_parent);
1337 if (!kobject_move(&dev->kobj, &old_parent->kobj)) {
Cornelia Huckc744aea2007-01-08 20:16:44 +01001338 if (new_parent)
1339 klist_remove(&dev->knode_parent);
Cornelia Huck8a824722006-11-20 17:07:51 +01001340 if (old_parent)
1341 klist_add_tail(&dev->knode_parent,
1342 &old_parent->klist_children);
1343 }
1344 put_device(new_parent);
1345 goto out;
1346 }
1347out_put:
1348 put_device(old_parent);
1349out:
1350 put_device(dev);
1351 return error;
1352}
1353
1354EXPORT_SYMBOL_GPL(device_move);