blob: b78fc1e68264872a196c6a7b1e454b080a9831bd [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
111static struct kobj_type ktype_device = {
112 .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
121 if (ktype == &ktype_device) {
122 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 Sievers312c0042005-11-16 09:00:00 +0100144static int dev_uevent(struct kset *kset, struct kobject *kobj, char **envp,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145 int num_envp, char *buffer, int buffer_size)
146{
147 struct device *dev = to_dev(kobj);
148 int i = 0;
149 int length = 0;
150 int retval = 0;
151
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700152 /* add the major/minor if present */
153 if (MAJOR(dev->devt)) {
154 add_uevent_var(envp, num_envp, &i,
155 buffer, buffer_size, &length,
156 "MAJOR=%u", MAJOR(dev->devt));
157 add_uevent_var(envp, num_envp, &i,
158 buffer, buffer_size, &length,
159 "MINOR=%u", MINOR(dev->devt));
160 }
161
Kay Sievers414264f2007-03-12 21:08:57 +0100162 if (dev->type && dev->type->name)
163 add_uevent_var(envp, num_envp, &i,
164 buffer, buffer_size, &length,
165 "DEVTYPE=%s", dev->type->name);
166
Kay Sievers239378f2006-10-07 21:54:55 +0200167 if (dev->driver)
Kay Sieversd81d9d62006-08-13 06:17:09 +0200168 add_uevent_var(envp, num_envp, &i,
169 buffer, buffer_size, &length,
170 "DRIVER=%s", dev->driver->name);
Kay Sievers239378f2006-10-07 21:54:55 +0200171
Kay Sieversa87cb2a2006-09-14 11:23:28 +0200172#ifdef CONFIG_SYSFS_DEPRECATED
Kay Sievers239378f2006-10-07 21:54:55 +0200173 if (dev->class) {
174 struct device *parent = dev->parent;
175
176 /* find first bus device in parent chain */
177 while (parent && !parent->bus)
178 parent = parent->parent;
179 if (parent && parent->bus) {
180 const char *path;
181
182 path = kobject_get_path(&parent->kobj, GFP_KERNEL);
183 add_uevent_var(envp, num_envp, &i,
184 buffer, buffer_size, &length,
185 "PHYSDEVPATH=%s", path);
186 kfree(path);
187
188 add_uevent_var(envp, num_envp, &i,
189 buffer, buffer_size, &length,
190 "PHYSDEVBUS=%s", parent->bus->name);
191
192 if (parent->driver)
193 add_uevent_var(envp, num_envp, &i,
194 buffer, buffer_size, &length,
195 "PHYSDEVDRIVER=%s", parent->driver->name);
196 }
197 } else if (dev->bus) {
Kay Sievers312c0042005-11-16 09:00:00 +0100198 add_uevent_var(envp, num_envp, &i,
199 buffer, buffer_size, &length,
Kay Sievers239378f2006-10-07 21:54:55 +0200200 "PHYSDEVBUS=%s", dev->bus->name);
201
202 if (dev->driver)
203 add_uevent_var(envp, num_envp, &i,
204 buffer, buffer_size, &length,
205 "PHYSDEVDRIVER=%s", dev->driver->name);
Kay Sieversd81d9d62006-08-13 06:17:09 +0200206 }
Kay Sievers239378f2006-10-07 21:54:55 +0200207#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208
209 /* terminate, set to next free slot, shrink available space */
210 envp[i] = NULL;
211 envp = &envp[i];
212 num_envp -= i;
213 buffer = &buffer[length];
214 buffer_size -= length;
215
Kay Sievers312c0042005-11-16 09:00:00 +0100216 if (dev->bus && dev->bus->uevent) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217 /* have the bus specific function add its stuff */
Kay Sievers312c0042005-11-16 09:00:00 +0100218 retval = dev->bus->uevent(dev, envp, num_envp, buffer, buffer_size);
Kay Sieversf9f852d2006-10-07 21:54:55 +0200219 if (retval)
220 pr_debug ("%s: bus uevent() returned %d\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700221 __FUNCTION__, retval);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 }
223
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700224 if (dev->class && dev->class->dev_uevent) {
225 /* have the class specific function add its stuff */
226 retval = dev->class->dev_uevent(dev, envp, num_envp, buffer, buffer_size);
Kay Sieversf9f852d2006-10-07 21:54:55 +0200227 if (retval)
228 pr_debug("%s: class uevent() returned %d\n",
229 __FUNCTION__, retval);
230 }
231
232 if (dev->type && dev->type->uevent) {
233 /* have the device type specific fuction add its stuff */
234 retval = dev->type->uevent(dev, envp, num_envp, buffer, buffer_size);
235 if (retval)
236 pr_debug("%s: dev_type uevent() returned %d\n",
237 __FUNCTION__, retval);
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700238 }
239
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240 return retval;
241}
242
Kay Sievers312c0042005-11-16 09:00:00 +0100243static struct kset_uevent_ops device_uevent_ops = {
244 .filter = dev_uevent_filter,
245 .name = dev_uevent_name,
246 .uevent = dev_uevent,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247};
248
Kay Sievers16574dc2007-04-06 01:40:38 +0200249static ssize_t show_uevent(struct device *dev, struct device_attribute *attr,
250 char *buf)
251{
252 struct kobject *top_kobj;
253 struct kset *kset;
254 char *envp[32];
Greg Kroah-Hartmanc7308c82007-05-02 14:14:11 +0200255 char *data = NULL;
Kay Sievers16574dc2007-04-06 01:40:38 +0200256 char *pos;
257 int i;
258 size_t count = 0;
259 int retval;
260
261 /* search the kset, the device belongs to */
262 top_kobj = &dev->kobj;
263 if (!top_kobj->kset && top_kobj->parent) {
264 do {
265 top_kobj = top_kobj->parent;
266 } while (!top_kobj->kset && top_kobj->parent);
267 }
268 if (!top_kobj->kset)
269 goto out;
270 kset = top_kobj->kset;
271 if (!kset->uevent_ops || !kset->uevent_ops->uevent)
272 goto out;
273
274 /* respect filter */
275 if (kset->uevent_ops && kset->uevent_ops->filter)
276 if (!kset->uevent_ops->filter(kset, &dev->kobj))
277 goto out;
278
Greg Kroah-Hartmanc7308c82007-05-02 14:14:11 +0200279 data = (char *)get_zeroed_page(GFP_KERNEL);
280 if (!data)
281 return -ENOMEM;
282
Kay Sievers16574dc2007-04-06 01:40:38 +0200283 /* let the kset specific function add its keys */
284 pos = data;
285 retval = kset->uevent_ops->uevent(kset, &dev->kobj,
286 envp, ARRAY_SIZE(envp),
287 pos, PAGE_SIZE);
288 if (retval)
289 goto out;
290
291 /* copy keys to file */
292 for (i = 0; envp[i]; i++) {
293 pos = &buf[count];
294 count += sprintf(pos, "%s\n", envp[i]);
295 }
296out:
Greg Kroah-Hartmanc7308c82007-05-02 14:14:11 +0200297 free_page((unsigned long)data);
Kay Sievers16574dc2007-04-06 01:40:38 +0200298 return count;
299}
300
Kay Sieversa7fd6702005-10-01 14:49:43 +0200301static ssize_t store_uevent(struct device *dev, struct device_attribute *attr,
302 const char *buf, size_t count)
303{
Kay Sievers22af74f2007-04-06 01:40:38 +0200304 if (memcmp(buf, "add", 3) != 0)
305 dev_err(dev, "uevent: unsupported action-string; this will "
306 "be ignored in a future kernel version");
Kay Sievers312c0042005-11-16 09:00:00 +0100307 kobject_uevent(&dev->kobj, KOBJ_ADD);
Kay Sieversa7fd6702005-10-01 14:49:43 +0200308 return count;
309}
310
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500311static int device_add_attributes(struct device *dev,
312 struct device_attribute *attrs)
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700313{
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700314 int error = 0;
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500315 int i;
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700316
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500317 if (attrs) {
318 for (i = 0; attr_name(attrs[i]); i++) {
319 error = device_create_file(dev, &attrs[i]);
320 if (error)
321 break;
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700322 }
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500323 if (error)
324 while (--i >= 0)
325 device_remove_file(dev, &attrs[i]);
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700326 }
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700327 return error;
328}
329
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500330static void device_remove_attributes(struct device *dev,
331 struct device_attribute *attrs)
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700332{
333 int i;
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500334
335 if (attrs)
336 for (i = 0; attr_name(attrs[i]); i++)
337 device_remove_file(dev, &attrs[i]);
338}
339
340static int device_add_groups(struct device *dev,
341 struct attribute_group **groups)
342{
343 int error = 0;
344 int i;
345
346 if (groups) {
347 for (i = 0; groups[i]; i++) {
348 error = sysfs_create_group(&dev->kobj, groups[i]);
349 if (error) {
350 while (--i >= 0)
351 sysfs_remove_group(&dev->kobj, groups[i]);
352 break;
353 }
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700354 }
355 }
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500356 return error;
357}
358
359static void device_remove_groups(struct device *dev,
360 struct attribute_group **groups)
361{
362 int i;
363
364 if (groups)
365 for (i = 0; groups[i]; i++)
366 sysfs_remove_group(&dev->kobj, groups[i]);
Greg Kroah-Hartmande0ff002006-06-27 00:06:09 -0700367}
368
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700369static int device_add_attrs(struct device *dev)
370{
371 struct class *class = dev->class;
Kay Sieversf9f852d2006-10-07 21:54:55 +0200372 struct device_type *type = dev->type;
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500373 int error;
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700374
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500375 if (class) {
376 error = device_add_attributes(dev, class->dev_attrs);
Kay Sieversf9f852d2006-10-07 21:54:55 +0200377 if (error)
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500378 return error;
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700379 }
Kay Sieversf9f852d2006-10-07 21:54:55 +0200380
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500381 if (type) {
382 error = device_add_groups(dev, type->groups);
Kay Sieversf9f852d2006-10-07 21:54:55 +0200383 if (error)
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500384 goto err_remove_class_attrs;
Kay Sieversf9f852d2006-10-07 21:54:55 +0200385 }
386
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500387 error = device_add_groups(dev, dev->groups);
388 if (error)
389 goto err_remove_type_groups;
390
391 return 0;
392
393 err_remove_type_groups:
394 if (type)
395 device_remove_groups(dev, type->groups);
396 err_remove_class_attrs:
397 if (class)
398 device_remove_attributes(dev, class->dev_attrs);
399
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700400 return error;
401}
402
403static void device_remove_attrs(struct device *dev)
404{
405 struct class *class = dev->class;
Kay Sieversf9f852d2006-10-07 21:54:55 +0200406 struct device_type *type = dev->type;
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700407
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500408 device_remove_groups(dev, dev->groups);
Kay Sieversf9f852d2006-10-07 21:54:55 +0200409
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500410 if (type)
411 device_remove_groups(dev, type->groups);
412
413 if (class)
414 device_remove_attributes(dev, class->dev_attrs);
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700415}
416
417
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700418static ssize_t show_dev(struct device *dev, struct device_attribute *attr,
419 char *buf)
420{
421 return print_dev_t(buf, dev->devt);
422}
423
Martin Waitz0863afb2006-01-09 20:53:55 -0800424/*
425 * devices_subsys - structure to be registered with kobject core.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426 */
427
Kay Sievers312c0042005-11-16 09:00:00 +0100428decl_subsys(devices, &ktype_device, &device_uevent_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429
430
431/**
432 * device_create_file - create sysfs attribute file for device.
433 * @dev: device.
434 * @attr: device attribute descriptor.
435 */
436
437int device_create_file(struct device * dev, struct device_attribute * attr)
438{
439 int error = 0;
440 if (get_device(dev)) {
441 error = sysfs_create_file(&dev->kobj, &attr->attr);
442 put_device(dev);
443 }
444 return error;
445}
446
447/**
448 * device_remove_file - remove sysfs attribute file.
449 * @dev: device.
450 * @attr: device attribute descriptor.
451 */
452
453void device_remove_file(struct device * dev, struct device_attribute * attr)
454{
455 if (get_device(dev)) {
456 sysfs_remove_file(&dev->kobj, &attr->attr);
457 put_device(dev);
458 }
459}
460
Greg Kroah-Hartman2589f1882006-09-19 09:39:19 -0700461/**
462 * device_create_bin_file - create sysfs binary attribute file for device.
463 * @dev: device.
464 * @attr: device binary attribute descriptor.
465 */
466int device_create_bin_file(struct device *dev, struct bin_attribute *attr)
467{
468 int error = -EINVAL;
469 if (dev)
470 error = sysfs_create_bin_file(&dev->kobj, attr);
471 return error;
472}
473EXPORT_SYMBOL_GPL(device_create_bin_file);
474
475/**
476 * device_remove_bin_file - remove sysfs binary attribute file
477 * @dev: device.
478 * @attr: device binary attribute descriptor.
479 */
480void device_remove_bin_file(struct device *dev, struct bin_attribute *attr)
481{
482 if (dev)
483 sysfs_remove_bin_file(&dev->kobj, attr);
484}
485EXPORT_SYMBOL_GPL(device_remove_bin_file);
486
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400487/**
Alan Stern523ded72007-04-26 00:12:04 -0700488 * device_schedule_callback_owner - helper to schedule a callback for a device
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400489 * @dev: device.
490 * @func: callback function to invoke later.
Alan Stern523ded72007-04-26 00:12:04 -0700491 * @owner: module owning the callback routine
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400492 *
493 * Attribute methods must not unregister themselves or their parent device
494 * (which would amount to the same thing). Attempts to do so will deadlock,
495 * since unregistration is mutually exclusive with driver callbacks.
496 *
497 * Instead methods can call this routine, which will attempt to allocate
498 * and schedule a workqueue request to call back @func with @dev as its
499 * argument in the workqueue's process context. @dev will be pinned until
500 * @func returns.
501 *
Alan Stern523ded72007-04-26 00:12:04 -0700502 * This routine is usually called via the inline device_schedule_callback(),
503 * which automatically sets @owner to THIS_MODULE.
504 *
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400505 * Returns 0 if the request was submitted, -ENOMEM if storage could not
Alan Stern523ded72007-04-26 00:12:04 -0700506 * be allocated, -ENODEV if a reference to @owner isn't available.
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400507 *
508 * NOTE: This routine won't work if CONFIG_SYSFS isn't set! It uses an
509 * underlying sysfs routine (since it is intended for use by attribute
510 * methods), and if sysfs isn't available you'll get nothing but -ENOSYS.
511 */
Alan Stern523ded72007-04-26 00:12:04 -0700512int device_schedule_callback_owner(struct device *dev,
513 void (*func)(struct device *), struct module *owner)
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400514{
515 return sysfs_schedule_callback(&dev->kobj,
Alan Stern523ded72007-04-26 00:12:04 -0700516 (void (*)(void *)) func, dev, owner);
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400517}
Alan Stern523ded72007-04-26 00:12:04 -0700518EXPORT_SYMBOL_GPL(device_schedule_callback_owner);
Alan Sternd9a9cdf2007-03-15 15:50:34 -0400519
James Bottomley34bb61f2005-09-06 16:56:51 -0700520static void klist_children_get(struct klist_node *n)
521{
522 struct device *dev = container_of(n, struct device, knode_parent);
523
524 get_device(dev);
525}
526
527static void klist_children_put(struct klist_node *n)
528{
529 struct device *dev = container_of(n, struct device, knode_parent);
530
531 put_device(dev);
532}
533
Linus Torvalds1da177e2005-04-16 15:20:36 -0700534
535/**
536 * device_initialize - init device structure.
537 * @dev: device.
538 *
539 * This prepares the device for use by other layers,
540 * including adding it to the device hierarchy.
541 * It is the first half of device_register(), if called by
542 * that, though it can also be called separately, so one
543 * may use @dev's fields (e.g. the refcount).
544 */
545
546void device_initialize(struct device *dev)
547{
548 kobj_set_kset_s(dev, devices_subsys);
549 kobject_init(&dev->kobj);
James Bottomley34bb61f2005-09-06 16:56:51 -0700550 klist_init(&dev->klist_children, klist_children_get,
551 klist_children_put);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552 INIT_LIST_HEAD(&dev->dma_pools);
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700553 INIT_LIST_HEAD(&dev->node);
mochel@digitalimplant.orgaf703162005-03-21 10:41:04 -0800554 init_MUTEX(&dev->sem);
Tejun Heo9ac78492007-01-20 16:00:26 +0900555 spin_lock_init(&dev->devres_lock);
556 INIT_LIST_HEAD(&dev->devres_head);
David Brownell0ac85242005-09-12 19:39:34 -0700557 device_init_wakeup(dev, 0);
Christoph Hellwig87348132006-12-06 20:32:33 -0800558 set_dev_node(dev, -1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559}
560
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100561#ifdef CONFIG_SYSFS_DEPRECATED
Cornelia Huckc744aeae2007-01-08 20:16:44 +0100562static struct kobject * get_device_parent(struct device *dev,
563 struct device *parent)
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100564{
565 /* Set the parent to the class, not the parent device */
566 /* this keeps sysfs from having a symlink to make old udevs happy */
567 if (dev->class)
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700568 return &dev->class->subsys.kobj;
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100569 else if (parent)
Cornelia Huckc744aeae2007-01-08 20:16:44 +0100570 return &parent->kobj;
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100571
Cornelia Huckc744aeae2007-01-08 20:16:44 +0100572 return NULL;
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100573}
574#else
Kay Sievers86406242007-03-14 03:25:56 +0100575static struct kobject *virtual_device_parent(struct device *dev)
Greg Kroah-Hartmanf0ee61a2006-10-23 10:40:54 -0700576{
Kay Sievers86406242007-03-14 03:25:56 +0100577 static struct kobject *virtual_dir = NULL;
Greg Kroah-Hartmanf0ee61a2006-10-23 10:40:54 -0700578
Kay Sievers86406242007-03-14 03:25:56 +0100579 if (!virtual_dir)
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700580 virtual_dir = kobject_add_dir(&devices_subsys.kobj, "virtual");
Greg Kroah-Hartmanf0ee61a2006-10-23 10:40:54 -0700581
Kay Sievers86406242007-03-14 03:25:56 +0100582 return virtual_dir;
Greg Kroah-Hartmanf0ee61a2006-10-23 10:40:54 -0700583}
584
Cornelia Huckc744aeae2007-01-08 20:16:44 +0100585static struct kobject * get_device_parent(struct device *dev,
586 struct device *parent)
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100587{
Kay Sievers86406242007-03-14 03:25:56 +0100588 if (dev->class) {
589 struct kobject *kobj = NULL;
590 struct kobject *parent_kobj;
591 struct kobject *k;
592
593 /*
594 * If we have no parent, we live in "virtual".
595 * Class-devices with a bus-device as parent, live
596 * in a class-directory to prevent namespace collisions.
597 */
598 if (parent == NULL)
599 parent_kobj = virtual_device_parent(dev);
600 else if (parent->class)
601 return &parent->kobj;
602 else
603 parent_kobj = &parent->kobj;
604
605 /* find our class-directory at the parent and reference it */
606 spin_lock(&dev->class->class_dirs.list_lock);
607 list_for_each_entry(k, &dev->class->class_dirs.list, entry)
608 if (k->parent == parent_kobj) {
609 kobj = kobject_get(k);
610 break;
611 }
612 spin_unlock(&dev->class->class_dirs.list_lock);
613 if (kobj)
614 return kobj;
615
616 /* or create a new class-directory at the parent device */
617 return kobject_kset_add_dir(&dev->class->class_dirs,
618 parent_kobj, dev->class->name);
619 }
620
621 if (parent)
Cornelia Huckc744aeae2007-01-08 20:16:44 +0100622 return &parent->kobj;
623 return NULL;
624}
Cornelia Huckc744aeae2007-01-08 20:16:44 +0100625#endif
Kay Sievers86406242007-03-14 03:25:56 +0100626
Cornelia Huckc744aeae2007-01-08 20:16:44 +0100627static int setup_parent(struct device *dev, struct device *parent)
628{
629 struct kobject *kobj;
630 kobj = get_device_parent(dev, parent);
631 if (IS_ERR(kobj))
632 return PTR_ERR(kobj);
633 if (kobj)
634 dev->kobj.parent = kobj;
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100635 return 0;
636}
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100637
Linus Torvalds1da177e2005-04-16 15:20:36 -0700638/**
639 * device_add - add device to device hierarchy.
640 * @dev: device.
641 *
642 * This is part 2 of device_register(), though may be called
643 * separately _iff_ device_initialize() has been called separately.
644 *
645 * This adds it to the kobject hierarchy via kobject_add(), adds it
646 * to the global and sibling lists for the device, then
647 * adds it to the other relevant subsystems of the driver model.
648 */
649int device_add(struct device *dev)
650{
651 struct device *parent = NULL;
Greg Kroah-Hartmane9a7d302006-06-20 13:59:20 -0700652 char *class_name = NULL;
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200653 struct class_interface *class_intf;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654 int error = -EINVAL;
655
656 dev = get_device(dev);
657 if (!dev || !strlen(dev->bus_id))
658 goto Error;
659
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100660 pr_debug("DEV: registering device: ID = '%s'\n", dev->bus_id);
Greg Kroah-Hartmanc205ef42006-08-07 22:19:37 -0700661
Linus Torvalds1da177e2005-04-16 15:20:36 -0700662 parent = get_device(dev->parent);
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100663 error = setup_parent(dev, parent);
664 if (error)
665 goto Error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666
667 /* first, register with generic layer. */
668 kobject_set_name(&dev->kobj, "%s", dev->bus_id);
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100669 error = kobject_add(&dev->kobj);
670 if (error)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671 goto Error;
Kay Sieversa7fd6702005-10-01 14:49:43 +0200672
Brian Walsh37022642006-08-14 22:43:19 -0700673 /* notify platform of device entry */
674 if (platform_notify)
675 platform_notify(dev);
676
Benjamin Herrenschmidt116af372006-10-25 13:44:59 +1000677 /* notify clients of device entry (new way) */
678 if (dev->bus)
679 blocking_notifier_call_chain(&dev->bus->bus_notifier,
680 BUS_NOTIFY_ADD_DEVICE, dev);
681
Kay Sieversa7fd6702005-10-01 14:49:43 +0200682 dev->uevent_attr.attr.name = "uevent";
Kay Sievers16574dc2007-04-06 01:40:38 +0200683 dev->uevent_attr.attr.mode = S_IRUGO | S_IWUSR;
Kay Sieversa7fd6702005-10-01 14:49:43 +0200684 if (dev->driver)
685 dev->uevent_attr.attr.owner = dev->driver->owner;
686 dev->uevent_attr.store = store_uevent;
Kay Sievers16574dc2007-04-06 01:40:38 +0200687 dev->uevent_attr.show = show_uevent;
Cornelia Hucka306eea2006-09-22 11:37:13 +0200688 error = device_create_file(dev, &dev->uevent_attr);
689 if (error)
690 goto attrError;
Kay Sieversa7fd6702005-10-01 14:49:43 +0200691
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700692 if (MAJOR(dev->devt)) {
693 struct device_attribute *attr;
694 attr = kzalloc(sizeof(*attr), GFP_KERNEL);
695 if (!attr) {
696 error = -ENOMEM;
Cornelia Hucka306eea2006-09-22 11:37:13 +0200697 goto ueventattrError;
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700698 }
699 attr->attr.name = "dev";
700 attr->attr.mode = S_IRUGO;
701 if (dev->driver)
702 attr->attr.owner = dev->driver->owner;
703 attr->show = show_dev;
704 error = device_create_file(dev, attr);
705 if (error) {
706 kfree(attr);
Cornelia Hucka306eea2006-09-22 11:37:13 +0200707 goto ueventattrError;
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700708 }
709
710 dev->devt_attr = attr;
711 }
712
Kay Sieversb9d9c822006-06-15 15:31:56 +0200713 if (dev->class) {
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700714 sysfs_create_link(&dev->kobj, &dev->class->subsys.kobj,
Kay Sieversb9d9c822006-06-15 15:31:56 +0200715 "subsystem");
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100716 /* If this is not a "fake" compatible device, then create the
717 * symlink from the class to the device. */
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700718 if (dev->kobj.parent != &dev->class->subsys.kobj)
719 sysfs_create_link(&dev->class->subsys.kobj,
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100720 &dev->kobj, dev->bus_id);
Greg Kroah-Hartman64bb5d22006-06-28 16:19:58 -0700721 if (parent) {
Cornelia Huckcb360bb2006-11-27 10:35:05 +0100722 sysfs_create_link(&dev->kobj, &dev->parent->kobj,
723 "device");
Greg Kroah-Hartmanf7f34612007-03-06 12:55:53 -0800724#ifdef CONFIG_SYSFS_DEPRECATED
Cornelia Huckcb360bb2006-11-27 10:35:05 +0100725 class_name = make_class_name(dev->class->name,
726 &dev->kobj);
727 if (class_name)
728 sysfs_create_link(&dev->parent->kobj,
729 &dev->kobj, class_name);
Kay Sievers99ef3ef2006-09-14 11:23:28 +0200730#endif
Greg Kroah-Hartmanf7f34612007-03-06 12:55:53 -0800731 }
Kay Sieversb9d9c822006-06-15 15:31:56 +0200732 }
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700733
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700734 if ((error = device_add_attrs(dev)))
735 goto AttrsError;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700736 if ((error = device_pm_add(dev)))
737 goto PMError;
738 if ((error = bus_add_device(dev)))
739 goto BusError;
Cornelia Huck83b5fb4c2007-03-29 11:12:11 +0200740 kobject_uevent(&dev->kobj, KOBJ_ADD);
Cornelia Huckc6a46692007-02-05 16:15:26 -0800741 bus_attach_device(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742 if (parent)
James Bottomleyd856f1e32005-08-19 09:14:01 -0400743 klist_add_tail(&dev->knode_parent, &parent->klist_children);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744
Greg Kroah-Hartman5d9fd162006-06-22 17:17:32 -0700745 if (dev->class) {
Greg Kroah-Hartman5d9fd162006-06-22 17:17:32 -0700746 down(&dev->class->sem);
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200747 /* tie the class to the device */
Greg Kroah-Hartman5d9fd162006-06-22 17:17:32 -0700748 list_add_tail(&dev->node, &dev->class->devices);
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200749
750 /* notify any interfaces that the device is here */
751 list_for_each_entry(class_intf, &dev->class->interfaces, node)
752 if (class_intf->add_dev)
753 class_intf->add_dev(dev, class_intf);
Greg Kroah-Hartman5d9fd162006-06-22 17:17:32 -0700754 up(&dev->class->sem);
755 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756 Done:
Dmitry Torokhov621a1672007-03-10 01:37:34 -0500757 kfree(class_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700758 put_device(dev);
759 return error;
760 BusError:
761 device_pm_remove(dev);
762 PMError:
Benjamin Herrenschmidt116af372006-10-25 13:44:59 +1000763 if (dev->bus)
764 blocking_notifier_call_chain(&dev->bus->bus_notifier,
765 BUS_NOTIFY_DEL_DEVICE, dev);
James Simmons82f0cf92007-02-21 17:44:51 +0000766 device_remove_attrs(dev);
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700767 AttrsError:
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700768 if (dev->devt_attr) {
769 device_remove_file(dev, dev->devt_attr);
770 kfree(dev->devt_attr);
771 }
James Simmons82f0cf92007-02-21 17:44:51 +0000772
773 if (dev->class) {
774 sysfs_remove_link(&dev->kobj, "subsystem");
775 /* If this is not a "fake" compatible device, remove the
776 * symlink from the class to the device. */
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700777 if (dev->kobj.parent != &dev->class->subsys.kobj)
778 sysfs_remove_link(&dev->class->subsys.kobj,
James Simmons82f0cf92007-02-21 17:44:51 +0000779 dev->bus_id);
James Simmons82f0cf92007-02-21 17:44:51 +0000780 if (parent) {
Greg Kroah-Hartmanf7f34612007-03-06 12:55:53 -0800781#ifdef CONFIG_SYSFS_DEPRECATED
James Simmons82f0cf92007-02-21 17:44:51 +0000782 char *class_name = make_class_name(dev->class->name,
783 &dev->kobj);
784 if (class_name)
785 sysfs_remove_link(&dev->parent->kobj,
786 class_name);
787 kfree(class_name);
Greg Kroah-Hartmanf7f34612007-03-06 12:55:53 -0800788#endif
James Simmons82f0cf92007-02-21 17:44:51 +0000789 sysfs_remove_link(&dev->kobj, "device");
790 }
James Simmons82f0cf92007-02-21 17:44:51 +0000791 }
Cornelia Hucka306eea2006-09-22 11:37:13 +0200792 ueventattrError:
793 device_remove_file(dev, &dev->uevent_attr);
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700794 attrError:
Kay Sievers312c0042005-11-16 09:00:00 +0100795 kobject_uevent(&dev->kobj, KOBJ_REMOVE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796 kobject_del(&dev->kobj);
797 Error:
798 if (parent)
799 put_device(parent);
800 goto Done;
801}
802
803
804/**
805 * device_register - register a device with the system.
806 * @dev: pointer to the device structure
807 *
808 * This happens in two clean steps - initialize the device
809 * and add it to the system. The two steps can be called
810 * separately, but this is the easiest and most common.
811 * I.e. you should only call the two helpers separately if
812 * have a clearly defined need to use and refcount the device
813 * before it is added to the hierarchy.
814 */
815
816int device_register(struct device *dev)
817{
818 device_initialize(dev);
819 return device_add(dev);
820}
821
822
823/**
824 * get_device - increment reference count for device.
825 * @dev: device.
826 *
827 * This simply forwards the call to kobject_get(), though
828 * we do take care to provide for the case that we get a NULL
829 * pointer passed in.
830 */
831
832struct device * get_device(struct device * dev)
833{
834 return dev ? to_dev(kobject_get(&dev->kobj)) : NULL;
835}
836
837
838/**
839 * put_device - decrement reference count.
840 * @dev: device in question.
841 */
842void put_device(struct device * dev)
843{
844 if (dev)
845 kobject_put(&dev->kobj);
846}
847
848
849/**
850 * device_del - delete device from system.
851 * @dev: device.
852 *
853 * This is the first part of the device unregistration
854 * sequence. This removes the device from the lists we control
855 * from here, has it removed from the other driver model
856 * subsystems it was added to in device_add(), and removes it
857 * from the kobject hierarchy.
858 *
859 * NOTE: this should be called manually _iff_ device_add() was
860 * also called manually.
861 */
862
863void device_del(struct device * dev)
864{
865 struct device * parent = dev->parent;
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200866 struct class_interface *class_intf;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868 if (parent)
Patrick Mocheld62c0f92005-06-24 08:39:33 -0700869 klist_del(&dev->knode_parent);
Catalin Marinas82189b92006-11-25 11:09:30 -0800870 if (dev->devt_attr) {
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -0700871 device_remove_file(dev, dev->devt_attr);
Catalin Marinas82189b92006-11-25 11:09:30 -0800872 kfree(dev->devt_attr);
873 }
Kay Sieversb9d9c822006-06-15 15:31:56 +0200874 if (dev->class) {
875 sysfs_remove_link(&dev->kobj, "subsystem");
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100876 /* If this is not a "fake" compatible device, remove the
877 * symlink from the class to the device. */
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700878 if (dev->kobj.parent != &dev->class->subsys.kobj)
879 sysfs_remove_link(&dev->class->subsys.kobj,
Greg Kroah-Hartman40fa5422006-10-24 00:37:58 +0100880 dev->bus_id);
Greg Kroah-Hartman64bb5d22006-06-28 16:19:58 -0700881 if (parent) {
Greg Kroah-Hartmanf7f34612007-03-06 12:55:53 -0800882#ifdef CONFIG_SYSFS_DEPRECATED
Kay Sievers99ef3ef2006-09-14 11:23:28 +0200883 char *class_name = make_class_name(dev->class->name,
884 &dev->kobj);
Cornelia Huckcb360bb2006-11-27 10:35:05 +0100885 if (class_name)
886 sysfs_remove_link(&dev->parent->kobj,
887 class_name);
Kay Sievers99ef3ef2006-09-14 11:23:28 +0200888 kfree(class_name);
Greg Kroah-Hartmanf7f34612007-03-06 12:55:53 -0800889#endif
Kay Sievers99ef3ef2006-09-14 11:23:28 +0200890 sysfs_remove_link(&dev->kobj, "device");
Greg Kroah-Hartman64bb5d22006-06-28 16:19:58 -0700891 }
Kay Sievers99ef3ef2006-09-14 11:23:28 +0200892
Greg Kroah-Hartman5d9fd162006-06-22 17:17:32 -0700893 down(&dev->class->sem);
Greg Kroah-Hartmanc47ed212006-09-13 15:34:05 +0200894 /* notify any interfaces that the device is now gone */
895 list_for_each_entry(class_intf, &dev->class->interfaces, node)
896 if (class_intf->remove_dev)
897 class_intf->remove_dev(dev, class_intf);
898 /* remove the device from the class list */
Greg Kroah-Hartman5d9fd162006-06-22 17:17:32 -0700899 list_del_init(&dev->node);
900 up(&dev->class->sem);
Kay Sievers86406242007-03-14 03:25:56 +0100901
902 /* If we live in a parent class-directory, unreference it */
903 if (dev->kobj.parent->kset == &dev->class->class_dirs) {
904 struct device *d;
905 int other = 0;
906
907 /*
908 * if we are the last child of our class, delete
909 * our class-directory at this parent
910 */
911 down(&dev->class->sem);
912 list_for_each_entry(d, &dev->class->devices, node) {
913 if (d == dev)
914 continue;
915 if (d->kobj.parent == dev->kobj.parent) {
916 other = 1;
917 break;
918 }
919 }
920 if (!other)
921 kobject_del(dev->kobj.parent);
922
923 kobject_put(dev->kobj.parent);
924 up(&dev->class->sem);
925 }
Kay Sieversb9d9c822006-06-15 15:31:56 +0200926 }
Kay Sieversa7fd6702005-10-01 14:49:43 +0200927 device_remove_file(dev, &dev->uevent_attr);
Greg Kroah-Hartman2620efe2006-06-28 16:19:58 -0700928 device_remove_attrs(dev);
Benjamin Herrenschmidt28953532006-11-08 19:46:14 -0800929 bus_remove_device(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700930
Tejun Heo2f8d16a2007-03-09 19:34:19 +0900931 /*
932 * Some platform devices are driven without driver attached
933 * and managed resources may have been acquired. Make sure
934 * all resources are released.
935 */
936 devres_release_all(dev);
937
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938 /* Notify the platform of the removal, in case they
939 * need to do anything...
940 */
941 if (platform_notify_remove)
942 platform_notify_remove(dev);
Benjamin Herrenschmidt116af372006-10-25 13:44:59 +1000943 if (dev->bus)
944 blocking_notifier_call_chain(&dev->bus->bus_notifier,
945 BUS_NOTIFY_DEL_DEVICE, dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700946 device_pm_remove(dev);
Kay Sievers312c0042005-11-16 09:00:00 +0100947 kobject_uevent(&dev->kobj, KOBJ_REMOVE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700948 kobject_del(&dev->kobj);
949 if (parent)
950 put_device(parent);
951}
952
953/**
954 * device_unregister - unregister device from system.
955 * @dev: device going away.
956 *
957 * We do this in two parts, like we do device_register(). First,
958 * we remove it from all the subsystems with device_del(), then
959 * we decrement the reference count via put_device(). If that
960 * is the final reference count, the device will be cleaned up
961 * via device_release() above. Otherwise, the structure will
962 * stick around until the final reference to the device is dropped.
963 */
964void device_unregister(struct device * dev)
965{
966 pr_debug("DEV: Unregistering device. ID = '%s'\n", dev->bus_id);
967 device_del(dev);
968 put_device(dev);
969}
970
971
mochel@digitalimplant.org36239572005-03-24 19:08:30 -0800972static struct device * next_device(struct klist_iter * i)
973{
974 struct klist_node * n = klist_next(i);
975 return n ? container_of(n, struct device, knode_parent) : NULL;
976}
977
Linus Torvalds1da177e2005-04-16 15:20:36 -0700978/**
979 * device_for_each_child - device child iterator.
Randy Dunlapc41455f2005-10-23 11:59:14 -0700980 * @parent: parent struct device.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981 * @data: data for the callback.
982 * @fn: function to be called for each device.
983 *
Randy Dunlapc41455f2005-10-23 11:59:14 -0700984 * Iterate over @parent's child devices, and call @fn for each,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985 * passing it @data.
986 *
987 * We check the return of @fn each time. If it returns anything
988 * other than 0, we break out and return that value.
989 */
mochel@digitalimplant.org36239572005-03-24 19:08:30 -0800990int device_for_each_child(struct device * parent, void * data,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700991 int (*fn)(struct device *, void *))
992{
mochel@digitalimplant.org36239572005-03-24 19:08:30 -0800993 struct klist_iter i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700994 struct device * child;
995 int error = 0;
996
mochel@digitalimplant.org36239572005-03-24 19:08:30 -0800997 klist_iter_init(&parent->klist_children, &i);
998 while ((child = next_device(&i)) && !error)
999 error = fn(child, data);
1000 klist_iter_exit(&i);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001 return error;
1002}
1003
Cornelia Huck5ab69982006-11-16 15:42:07 +01001004/**
1005 * device_find_child - device iterator for locating a particular device.
1006 * @parent: parent struct device
1007 * @data: Data to pass to match function
1008 * @match: Callback function to check device
1009 *
1010 * This is similar to the device_for_each_child() function above, but it
1011 * returns a reference to a device that is 'found' for later use, as
1012 * determined by the @match callback.
1013 *
1014 * The callback should return 0 if the device doesn't match and non-zero
1015 * if it does. If the callback returns non-zero and a reference to the
1016 * current device can be obtained, this function will return to the caller
1017 * and not iterate over any more devices.
1018 */
1019struct device * device_find_child(struct device *parent, void *data,
1020 int (*match)(struct device *, void *))
1021{
1022 struct klist_iter i;
1023 struct device *child;
1024
1025 if (!parent)
1026 return NULL;
1027
1028 klist_iter_init(&parent->klist_children, &i);
1029 while ((child = next_device(&i)))
1030 if (match(child, data) && get_device(child))
1031 break;
1032 klist_iter_exit(&i);
1033 return child;
1034}
1035
Linus Torvalds1da177e2005-04-16 15:20:36 -07001036int __init devices_init(void)
1037{
1038 return subsystem_register(&devices_subsys);
1039}
1040
1041EXPORT_SYMBOL_GPL(device_for_each_child);
Cornelia Huck5ab69982006-11-16 15:42:07 +01001042EXPORT_SYMBOL_GPL(device_find_child);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001043
1044EXPORT_SYMBOL_GPL(device_initialize);
1045EXPORT_SYMBOL_GPL(device_add);
1046EXPORT_SYMBOL_GPL(device_register);
1047
1048EXPORT_SYMBOL_GPL(device_del);
1049EXPORT_SYMBOL_GPL(device_unregister);
1050EXPORT_SYMBOL_GPL(get_device);
1051EXPORT_SYMBOL_GPL(put_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001052
1053EXPORT_SYMBOL_GPL(device_create_file);
1054EXPORT_SYMBOL_GPL(device_remove_file);
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001055
1056
1057static void device_create_release(struct device *dev)
1058{
1059 pr_debug("%s called for %s\n", __FUNCTION__, dev->bus_id);
1060 kfree(dev);
1061}
1062
1063/**
1064 * device_create - creates a device and registers it with sysfs
Henrik Kretzschmar42734da2006-07-05 00:53:19 +02001065 * @class: pointer to the struct class that this device should be registered to
1066 * @parent: pointer to the parent struct device of this new device, if any
1067 * @devt: the dev_t for the char device to be added
1068 * @fmt: string for the device's name
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001069 *
Henrik Kretzschmar42734da2006-07-05 00:53:19 +02001070 * This function can be used by char device classes. A struct device
1071 * will be created in sysfs, registered to the specified class.
1072 *
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001073 * A "dev" file will be created, showing the dev_t for the device, if
1074 * the dev_t is not 0,0.
Henrik Kretzschmar42734da2006-07-05 00:53:19 +02001075 * If a pointer to a parent struct device is passed in, the newly created
1076 * struct device will be a child of that device in sysfs.
1077 * The pointer to the struct device will be returned from the call.
1078 * Any further sysfs files that might be required can be created using this
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001079 * pointer.
1080 *
1081 * Note: the struct class passed to this function must have previously
1082 * been created with a call to class_create().
1083 */
1084struct device *device_create(struct class *class, struct device *parent,
Greg Kroah-Hartman5cbe5f82006-08-10 01:19:19 -04001085 dev_t devt, const char *fmt, ...)
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001086{
1087 va_list args;
1088 struct device *dev = NULL;
1089 int retval = -ENODEV;
1090
1091 if (class == NULL || IS_ERR(class))
1092 goto error;
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001093
1094 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1095 if (!dev) {
1096 retval = -ENOMEM;
1097 goto error;
1098 }
1099
1100 dev->devt = devt;
1101 dev->class = class;
1102 dev->parent = parent;
1103 dev->release = device_create_release;
1104
1105 va_start(args, fmt);
1106 vsnprintf(dev->bus_id, BUS_ID_SIZE, fmt, args);
1107 va_end(args);
1108 retval = device_register(dev);
1109 if (retval)
1110 goto error;
1111
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001112 return dev;
1113
1114error:
1115 kfree(dev);
1116 return ERR_PTR(retval);
1117}
1118EXPORT_SYMBOL_GPL(device_create);
1119
1120/**
1121 * device_destroy - removes a device that was created with device_create()
Henrik Kretzschmar42734da2006-07-05 00:53:19 +02001122 * @class: pointer to the struct class that this device was registered with
1123 * @devt: the dev_t of the device that was previously registered
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001124 *
Henrik Kretzschmar42734da2006-07-05 00:53:19 +02001125 * This call unregisters and cleans up a device that was created with a
1126 * call to device_create().
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001127 */
1128void device_destroy(struct class *class, dev_t devt)
1129{
1130 struct device *dev = NULL;
1131 struct device *dev_tmp;
1132
1133 down(&class->sem);
1134 list_for_each_entry(dev_tmp, &class->devices, node) {
1135 if (dev_tmp->devt == devt) {
1136 dev = dev_tmp;
1137 break;
1138 }
1139 }
1140 up(&class->sem);
1141
Greg Kroah-Hartman5d9fd162006-06-22 17:17:32 -07001142 if (dev)
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001143 device_unregister(dev);
Greg Kroah-Hartman23681e42006-06-14 12:14:34 -07001144}
1145EXPORT_SYMBOL_GPL(device_destroy);
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001146
1147/**
1148 * device_rename - renames a device
1149 * @dev: the pointer to the struct device to be renamed
1150 * @new_name: the new name of the device
1151 */
1152int device_rename(struct device *dev, char *new_name)
1153{
1154 char *old_class_name = NULL;
1155 char *new_class_name = NULL;
1156 char *old_symlink_name = NULL;
1157 int error;
1158
1159 dev = get_device(dev);
1160 if (!dev)
1161 return -EINVAL;
1162
1163 pr_debug("DEVICE: renaming '%s' to '%s'\n", dev->bus_id, new_name);
1164
Kay Sievers99ef3ef2006-09-14 11:23:28 +02001165#ifdef CONFIG_SYSFS_DEPRECATED
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001166 if ((dev->class) && (dev->parent))
1167 old_class_name = make_class_name(dev->class->name, &dev->kobj);
Kay Sievers99ef3ef2006-09-14 11:23:28 +02001168#endif
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001169
1170 if (dev->class) {
1171 old_symlink_name = kmalloc(BUS_ID_SIZE, GFP_KERNEL);
Jesper Juhl952ab432006-09-28 23:56:01 +02001172 if (!old_symlink_name) {
1173 error = -ENOMEM;
1174 goto out_free_old_class;
1175 }
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001176 strlcpy(old_symlink_name, dev->bus_id, BUS_ID_SIZE);
1177 }
1178
1179 strlcpy(dev->bus_id, new_name, BUS_ID_SIZE);
1180
1181 error = kobject_rename(&dev->kobj, new_name);
1182
Kay Sievers99ef3ef2006-09-14 11:23:28 +02001183#ifdef CONFIG_SYSFS_DEPRECATED
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001184 if (old_class_name) {
1185 new_class_name = make_class_name(dev->class->name, &dev->kobj);
1186 if (new_class_name) {
1187 sysfs_create_link(&dev->parent->kobj, &dev->kobj,
1188 new_class_name);
1189 sysfs_remove_link(&dev->parent->kobj, old_class_name);
1190 }
1191 }
Kay Sievers99ef3ef2006-09-14 11:23:28 +02001192#endif
1193
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001194 if (dev->class) {
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -07001195 sysfs_remove_link(&dev->class->subsys.kobj,
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001196 old_symlink_name);
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -07001197 sysfs_create_link(&dev->class->subsys.kobj, &dev->kobj,
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001198 dev->bus_id);
1199 }
1200 put_device(dev);
1201
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001202 kfree(new_class_name);
1203 kfree(old_symlink_name);
Jesper Juhl952ab432006-09-28 23:56:01 +02001204 out_free_old_class:
1205 kfree(old_class_name);
Greg Kroah-Hartmana2de48c2006-07-03 14:31:12 -07001206
1207 return error;
1208}
Johannes Berga2807db2007-02-28 12:38:31 +01001209EXPORT_SYMBOL_GPL(device_rename);
Cornelia Huck8a824722006-11-20 17:07:51 +01001210
1211static int device_move_class_links(struct device *dev,
1212 struct device *old_parent,
1213 struct device *new_parent)
1214{
Greg Kroah-Hartmanf7f34612007-03-06 12:55:53 -08001215 int error = 0;
Cornelia Huck8a824722006-11-20 17:07:51 +01001216#ifdef CONFIG_SYSFS_DEPRECATED
Cornelia Huck8a824722006-11-20 17:07:51 +01001217 char *class_name;
1218
1219 class_name = make_class_name(dev->class->name, &dev->kobj);
1220 if (!class_name) {
Cornelia Huckcb360bb2006-11-27 10:35:05 +01001221 error = -ENOMEM;
Cornelia Huck8a824722006-11-20 17:07:51 +01001222 goto out;
1223 }
1224 if (old_parent) {
1225 sysfs_remove_link(&dev->kobj, "device");
1226 sysfs_remove_link(&old_parent->kobj, class_name);
1227 }
Cornelia Huckc744aeae2007-01-08 20:16:44 +01001228 if (new_parent) {
1229 error = sysfs_create_link(&dev->kobj, &new_parent->kobj,
1230 "device");
1231 if (error)
1232 goto out;
1233 error = sysfs_create_link(&new_parent->kobj, &dev->kobj,
1234 class_name);
1235 if (error)
1236 sysfs_remove_link(&dev->kobj, "device");
1237 }
1238 else
1239 error = 0;
Cornelia Huck8a824722006-11-20 17:07:51 +01001240out:
1241 kfree(class_name);
1242 return error;
1243#else
Greg Kroah-Hartmanf7f34612007-03-06 12:55:53 -08001244 if (old_parent)
1245 sysfs_remove_link(&dev->kobj, "device");
1246 if (new_parent)
1247 error = sysfs_create_link(&dev->kobj, &new_parent->kobj,
1248 "device");
1249 return error;
Cornelia Huck8a824722006-11-20 17:07:51 +01001250#endif
1251}
1252
1253/**
1254 * device_move - moves a device to a new parent
1255 * @dev: the pointer to the struct device to be moved
Cornelia Huckc744aeae2007-01-08 20:16:44 +01001256 * @new_parent: the new parent of the device (can by NULL)
Cornelia Huck8a824722006-11-20 17:07:51 +01001257 */
1258int device_move(struct device *dev, struct device *new_parent)
1259{
1260 int error;
1261 struct device *old_parent;
Cornelia Huckc744aeae2007-01-08 20:16:44 +01001262 struct kobject *new_parent_kobj;
Cornelia Huck8a824722006-11-20 17:07:51 +01001263
1264 dev = get_device(dev);
1265 if (!dev)
1266 return -EINVAL;
1267
Cornelia Huck8a824722006-11-20 17:07:51 +01001268 new_parent = get_device(new_parent);
Cornelia Huckc744aeae2007-01-08 20:16:44 +01001269 new_parent_kobj = get_device_parent (dev, new_parent);
1270 if (IS_ERR(new_parent_kobj)) {
1271 error = PTR_ERR(new_parent_kobj);
1272 put_device(new_parent);
Cornelia Huck8a824722006-11-20 17:07:51 +01001273 goto out;
1274 }
1275 pr_debug("DEVICE: moving '%s' to '%s'\n", dev->bus_id,
Cornelia Huckc744aeae2007-01-08 20:16:44 +01001276 new_parent ? new_parent->bus_id : "<NULL>");
1277 error = kobject_move(&dev->kobj, new_parent_kobj);
Cornelia Huck8a824722006-11-20 17:07:51 +01001278 if (error) {
1279 put_device(new_parent);
1280 goto out;
1281 }
1282 old_parent = dev->parent;
1283 dev->parent = new_parent;
1284 if (old_parent)
Cornelia Huckacf02d22006-11-22 17:49:39 +01001285 klist_remove(&dev->knode_parent);
Cornelia Huckc744aeae2007-01-08 20:16:44 +01001286 if (new_parent)
1287 klist_add_tail(&dev->knode_parent, &new_parent->klist_children);
Cornelia Huck8a824722006-11-20 17:07:51 +01001288 if (!dev->class)
1289 goto out_put;
1290 error = device_move_class_links(dev, old_parent, new_parent);
1291 if (error) {
1292 /* We ignore errors on cleanup since we're hosed anyway... */
1293 device_move_class_links(dev, new_parent, old_parent);
1294 if (!kobject_move(&dev->kobj, &old_parent->kobj)) {
Cornelia Huckc744aeae2007-01-08 20:16:44 +01001295 if (new_parent)
1296 klist_remove(&dev->knode_parent);
Cornelia Huck8a824722006-11-20 17:07:51 +01001297 if (old_parent)
1298 klist_add_tail(&dev->knode_parent,
1299 &old_parent->klist_children);
1300 }
1301 put_device(new_parent);
1302 goto out;
1303 }
1304out_put:
1305 put_device(old_parent);
1306out:
1307 put_device(dev);
1308 return error;
1309}
1310
1311EXPORT_SYMBOL_GPL(device_move);