Merge with /pub/scm/linux/kernel/git/torvalds/linux-2.6.git
[linux-2.6] / drivers / base / class.c
1 /*
2  * class.c - basic device class management
3  *
4  * Copyright (c) 2002-3 Patrick Mochel
5  * Copyright (c) 2002-3 Open Source Development Labs
6  * Copyright (c) 2003-2004 Greg Kroah-Hartman
7  * Copyright (c) 2003-2004 IBM Corp.
8  *
9  * This file is released under the GPLv2
10  *
11  */
12
13 #include <linux/config.h>
14 #include <linux/device.h>
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/string.h>
18 #include <linux/kdev_t.h>
19 #include <linux/err.h>
20 #include <linux/slab.h>
21 #include "base.h"
22
23 #define to_class_attr(_attr) container_of(_attr, struct class_attribute, attr)
24 #define to_class(obj) container_of(obj, struct class, subsys.kset.kobj)
25
26 static ssize_t
27 class_attr_show(struct kobject * kobj, struct attribute * attr, char * buf)
28 {
29         struct class_attribute * class_attr = to_class_attr(attr);
30         struct class * dc = to_class(kobj);
31         ssize_t ret = -EIO;
32
33         if (class_attr->show)
34                 ret = class_attr->show(dc, buf);
35         return ret;
36 }
37
38 static ssize_t
39 class_attr_store(struct kobject * kobj, struct attribute * attr,
40                  const char * buf, size_t count)
41 {
42         struct class_attribute * class_attr = to_class_attr(attr);
43         struct class * dc = to_class(kobj);
44         ssize_t ret = -EIO;
45
46         if (class_attr->store)
47                 ret = class_attr->store(dc, buf, count);
48         return ret;
49 }
50
51 static void class_release(struct kobject * kobj)
52 {
53         struct class *class = to_class(kobj);
54
55         pr_debug("class '%s': release.\n", class->name);
56
57         if (class->class_release)
58                 class->class_release(class);
59         else
60                 pr_debug("class '%s' does not have a release() function, "
61                          "be careful\n", class->name);
62 }
63
64 static struct sysfs_ops class_sysfs_ops = {
65         .show   = class_attr_show,
66         .store  = class_attr_store,
67 };
68
69 static struct kobj_type ktype_class = {
70         .sysfs_ops      = &class_sysfs_ops,
71         .release        = class_release,
72 };
73
74 /* Hotplug events for classes go to the class_obj subsys */
75 static decl_subsys(class, &ktype_class, NULL);
76
77
78 int class_create_file(struct class * cls, const struct class_attribute * attr)
79 {
80         int error;
81         if (cls) {
82                 error = sysfs_create_file(&cls->subsys.kset.kobj, &attr->attr);
83         } else
84                 error = -EINVAL;
85         return error;
86 }
87
88 void class_remove_file(struct class * cls, const struct class_attribute * attr)
89 {
90         if (cls)
91                 sysfs_remove_file(&cls->subsys.kset.kobj, &attr->attr);
92 }
93
94 struct class * class_get(struct class * cls)
95 {
96         if (cls)
97                 return container_of(subsys_get(&cls->subsys), struct class, subsys);
98         return NULL;
99 }
100
101 void class_put(struct class * cls)
102 {
103         if (cls)
104                 subsys_put(&cls->subsys);
105 }
106
107
108 static int add_class_attrs(struct class * cls)
109 {
110         int i;
111         int error = 0;
112
113         if (cls->class_attrs) {
114                 for (i = 0; attr_name(cls->class_attrs[i]); i++) {
115                         error = class_create_file(cls,&cls->class_attrs[i]);
116                         if (error)
117                                 goto Err;
118                 }
119         }
120  Done:
121         return error;
122  Err:
123         while (--i >= 0)
124                 class_remove_file(cls,&cls->class_attrs[i]);
125         goto Done;
126 }
127
128 static void remove_class_attrs(struct class * cls)
129 {
130         int i;
131
132         if (cls->class_attrs) {
133                 for (i = 0; attr_name(cls->class_attrs[i]); i++)
134                         class_remove_file(cls,&cls->class_attrs[i]);
135         }
136 }
137
138 int class_register(struct class * cls)
139 {
140         int error;
141
142         pr_debug("device class '%s': registering\n", cls->name);
143
144         INIT_LIST_HEAD(&cls->children);
145         INIT_LIST_HEAD(&cls->interfaces);
146         init_MUTEX(&cls->sem);
147         error = kobject_set_name(&cls->subsys.kset.kobj, "%s", cls->name);
148         if (error)
149                 return error;
150
151         subsys_set_kset(cls, class_subsys);
152
153         error = subsystem_register(&cls->subsys);
154         if (!error) {
155                 error = add_class_attrs(class_get(cls));
156                 class_put(cls);
157         }
158         return error;
159 }
160
161 void class_unregister(struct class * cls)
162 {
163         pr_debug("device class '%s': unregistering\n", cls->name);
164         remove_class_attrs(cls);
165         subsystem_unregister(&cls->subsys);
166 }
167
168 static void class_create_release(struct class *cls)
169 {
170         pr_debug("%s called for %s\n", __FUNCTION__, cls->name);
171         kfree(cls);
172 }
173
174 static void class_device_create_release(struct class_device *class_dev)
175 {
176         pr_debug("%s called for %s\n", __FUNCTION__, class_dev->class_id);
177         kfree(class_dev);
178 }
179
180 /* needed to allow these devices to have parent class devices */
181 static int class_device_create_hotplug(struct class_device *class_dev,
182                                        char **envp, int num_envp,
183                                        char *buffer, int buffer_size)
184 {
185         pr_debug("%s called for %s\n", __FUNCTION__, class_dev->class_id);
186         return 0;
187 }
188
189 /**
190  * class_create - create a struct class structure
191  * @owner: pointer to the module that is to "own" this struct class
192  * @name: pointer to a string for the name of this class.
193  *
194  * This is used to create a struct class pointer that can then be used
195  * in calls to class_device_create().
196  *
197  * Note, the pointer created here is to be destroyed when finished by
198  * making a call to class_destroy().
199  */
200 struct class *class_create(struct module *owner, char *name)
201 {
202         struct class *cls;
203         int retval;
204
205         cls = kzalloc(sizeof(*cls), GFP_KERNEL);
206         if (!cls) {
207                 retval = -ENOMEM;
208                 goto error;
209         }
210
211         cls->name = name;
212         cls->owner = owner;
213         cls->class_release = class_create_release;
214         cls->release = class_device_create_release;
215
216         retval = class_register(cls);
217         if (retval)
218                 goto error;
219
220         return cls;
221
222 error:
223         kfree(cls);
224         return ERR_PTR(retval);
225 }
226
227 /**
228  * class_destroy - destroys a struct class structure
229  * @cs: pointer to the struct class that is to be destroyed
230  *
231  * Note, the pointer to be destroyed must have been created with a call
232  * to class_create().
233  */
234 void class_destroy(struct class *cls)
235 {
236         if ((cls == NULL) || (IS_ERR(cls)))
237                 return;
238
239         class_unregister(cls);
240 }
241
242 /* Class Device Stuff */
243
244 int class_device_create_file(struct class_device * class_dev,
245                              const struct class_device_attribute * attr)
246 {
247         int error = -EINVAL;
248         if (class_dev)
249                 error = sysfs_create_file(&class_dev->kobj, &attr->attr);
250         return error;
251 }
252
253 void class_device_remove_file(struct class_device * class_dev,
254                               const struct class_device_attribute * attr)
255 {
256         if (class_dev)
257                 sysfs_remove_file(&class_dev->kobj, &attr->attr);
258 }
259
260 int class_device_create_bin_file(struct class_device *class_dev,
261                                  struct bin_attribute *attr)
262 {
263         int error = -EINVAL;
264         if (class_dev)
265                 error = sysfs_create_bin_file(&class_dev->kobj, attr);
266         return error;
267 }
268
269 void class_device_remove_bin_file(struct class_device *class_dev,
270                                   struct bin_attribute *attr)
271 {
272         if (class_dev)
273                 sysfs_remove_bin_file(&class_dev->kobj, attr);
274 }
275
276 static ssize_t
277 class_device_attr_show(struct kobject * kobj, struct attribute * attr,
278                        char * buf)
279 {
280         struct class_device_attribute * class_dev_attr = to_class_dev_attr(attr);
281         struct class_device * cd = to_class_dev(kobj);
282         ssize_t ret = 0;
283
284         if (class_dev_attr->show)
285                 ret = class_dev_attr->show(cd, buf);
286         return ret;
287 }
288
289 static ssize_t
290 class_device_attr_store(struct kobject * kobj, struct attribute * attr,
291                         const char * buf, size_t count)
292 {
293         struct class_device_attribute * class_dev_attr = to_class_dev_attr(attr);
294         struct class_device * cd = to_class_dev(kobj);
295         ssize_t ret = 0;
296
297         if (class_dev_attr->store)
298                 ret = class_dev_attr->store(cd, buf, count);
299         return ret;
300 }
301
302 static struct sysfs_ops class_dev_sysfs_ops = {
303         .show   = class_device_attr_show,
304         .store  = class_device_attr_store,
305 };
306
307 static void class_dev_release(struct kobject * kobj)
308 {
309         struct class_device *cd = to_class_dev(kobj);
310         struct class * cls = cd->class;
311
312         pr_debug("device class '%s': release.\n", cd->class_id);
313
314         kfree(cd->devt_attr);
315         cd->devt_attr = NULL;
316
317         if (cd->release)
318                 cd->release(cd);
319         else if (cls->release)
320                 cls->release(cd);
321         else {
322                 printk(KERN_ERR "Class Device '%s' does not have a release() function, "
323                         "it is broken and must be fixed.\n",
324                         cd->class_id);
325                 WARN_ON(1);
326         }
327 }
328
329 static struct kobj_type ktype_class_device = {
330         .sysfs_ops      = &class_dev_sysfs_ops,
331         .release        = class_dev_release,
332 };
333
334 static int class_hotplug_filter(struct kset *kset, struct kobject *kobj)
335 {
336         struct kobj_type *ktype = get_ktype(kobj);
337
338         if (ktype == &ktype_class_device) {
339                 struct class_device *class_dev = to_class_dev(kobj);
340                 if (class_dev->class)
341                         return 1;
342         }
343         return 0;
344 }
345
346 static const char *class_hotplug_name(struct kset *kset, struct kobject *kobj)
347 {
348         struct class_device *class_dev = to_class_dev(kobj);
349
350         return class_dev->class->name;
351 }
352
353 static int class_hotplug(struct kset *kset, struct kobject *kobj, char **envp,
354                          int num_envp, char *buffer, int buffer_size)
355 {
356         struct class_device *class_dev = to_class_dev(kobj);
357         int i = 0;
358         int length = 0;
359         int retval = 0;
360
361         pr_debug("%s - name = %s\n", __FUNCTION__, class_dev->class_id);
362
363         if (class_dev->dev) {
364                 /* add physical device, backing this device  */
365                 struct device *dev = class_dev->dev;
366                 char *path = kobject_get_path(&dev->kobj, GFP_KERNEL);
367
368                 add_hotplug_env_var(envp, num_envp, &i, buffer, buffer_size,
369                                     &length, "PHYSDEVPATH=%s", path);
370                 kfree(path);
371
372                 if (dev->bus)
373                         add_hotplug_env_var(envp, num_envp, &i,
374                                             buffer, buffer_size, &length,
375                                             "PHYSDEVBUS=%s", dev->bus->name);
376
377                 if (dev->driver)
378                         add_hotplug_env_var(envp, num_envp, &i,
379                                             buffer, buffer_size, &length,
380                                             "PHYSDEVDRIVER=%s", dev->driver->name);
381         }
382
383         if (MAJOR(class_dev->devt)) {
384                 add_hotplug_env_var(envp, num_envp, &i,
385                                     buffer, buffer_size, &length,
386                                     "MAJOR=%u", MAJOR(class_dev->devt));
387
388                 add_hotplug_env_var(envp, num_envp, &i,
389                                     buffer, buffer_size, &length,
390                                     "MINOR=%u", MINOR(class_dev->devt));
391         }
392
393         /* terminate, set to next free slot, shrink available space */
394         envp[i] = NULL;
395         envp = &envp[i];
396         num_envp -= i;
397         buffer = &buffer[length];
398         buffer_size -= length;
399
400         if (class_dev->hotplug) {
401                 /* have the class device specific function add its stuff */
402                 retval = class_dev->hotplug(class_dev, envp, num_envp,
403                                             buffer, buffer_size);
404                 if (retval)
405                         pr_debug("class_dev->hotplug() returned %d\n", retval);
406         } else if (class_dev->class->hotplug) {
407                 /* have the class specific function add its stuff */
408                 retval = class_dev->class->hotplug(class_dev, envp, num_envp,
409                                                    buffer, buffer_size);
410                 if (retval)
411                         pr_debug("class->hotplug() returned %d\n", retval);
412         }
413
414         return retval;
415 }
416
417 static struct kset_hotplug_ops class_hotplug_ops = {
418         .filter =       class_hotplug_filter,
419         .name =         class_hotplug_name,
420         .hotplug =      class_hotplug,
421 };
422
423 static decl_subsys(class_obj, &ktype_class_device, &class_hotplug_ops);
424
425
426 static int class_device_add_attrs(struct class_device * cd)
427 {
428         int i;
429         int error = 0;
430         struct class * cls = cd->class;
431
432         if (cls->class_dev_attrs) {
433                 for (i = 0; attr_name(cls->class_dev_attrs[i]); i++) {
434                         error = class_device_create_file(cd,
435                                                          &cls->class_dev_attrs[i]);
436                         if (error)
437                                 goto Err;
438                 }
439         }
440  Done:
441         return error;
442  Err:
443         while (--i >= 0)
444                 class_device_remove_file(cd,&cls->class_dev_attrs[i]);
445         goto Done;
446 }
447
448 static void class_device_remove_attrs(struct class_device * cd)
449 {
450         int i;
451         struct class * cls = cd->class;
452
453         if (cls->class_dev_attrs) {
454                 for (i = 0; attr_name(cls->class_dev_attrs[i]); i++)
455                         class_device_remove_file(cd,&cls->class_dev_attrs[i]);
456         }
457 }
458
459 static ssize_t show_dev(struct class_device *class_dev, char *buf)
460 {
461         return print_dev_t(buf, class_dev->devt);
462 }
463
464 static ssize_t store_uevent(struct class_device *class_dev,
465                             const char *buf, size_t count)
466 {
467         kobject_hotplug(&class_dev->kobj, KOBJ_ADD);
468         return count;
469 }
470
471 void class_device_initialize(struct class_device *class_dev)
472 {
473         kobj_set_kset_s(class_dev, class_obj_subsys);
474         kobject_init(&class_dev->kobj);
475         INIT_LIST_HEAD(&class_dev->node);
476 }
477
478 static char *make_class_name(struct class_device *class_dev)
479 {
480         char *name;
481         int size;
482
483         size = strlen(class_dev->class->name) +
484                 strlen(kobject_name(&class_dev->kobj)) + 2;
485
486         name = kmalloc(size, GFP_KERNEL);
487         if (!name)
488                 return ERR_PTR(-ENOMEM);
489
490         strcpy(name, class_dev->class->name);
491         strcat(name, ":");
492         strcat(name, kobject_name(&class_dev->kobj));
493         return name;
494 }
495
496 int class_device_add(struct class_device *class_dev)
497 {
498         struct class *parent_class = NULL;
499         struct class_device *parent_class_dev = NULL;
500         struct class_interface *class_intf;
501         char *class_name = NULL;
502         int error = -EINVAL;
503
504         class_dev = class_device_get(class_dev);
505         if (!class_dev)
506                 return -EINVAL;
507
508         if (!strlen(class_dev->class_id))
509                 goto register_done;
510
511         parent_class = class_get(class_dev->class);
512         if (!parent_class)
513                 goto register_done;
514         parent_class_dev = class_device_get(class_dev->parent);
515
516         pr_debug("CLASS: registering class device: ID = '%s'\n",
517                  class_dev->class_id);
518
519         /* first, register with generic layer. */
520         kobject_set_name(&class_dev->kobj, "%s", class_dev->class_id);
521         if (parent_class_dev)
522                 class_dev->kobj.parent = &parent_class_dev->kobj;
523         else
524                 class_dev->kobj.parent = &parent_class->subsys.kset.kobj;
525
526         error = kobject_add(&class_dev->kobj);
527         if (error)
528                 goto register_done;
529
530         /* add the needed attributes to this device */
531         class_dev->uevent_attr.attr.name = "uevent";
532         class_dev->uevent_attr.attr.mode = S_IWUSR;
533         class_dev->uevent_attr.attr.owner = parent_class->owner;
534         class_dev->uevent_attr.store = store_uevent;
535         class_device_create_file(class_dev, &class_dev->uevent_attr);
536
537         if (MAJOR(class_dev->devt)) {
538                 struct class_device_attribute *attr;
539                 attr = kzalloc(sizeof(*attr), GFP_KERNEL);
540                 if (!attr) {
541                         error = -ENOMEM;
542                         kobject_del(&class_dev->kobj);
543                         goto register_done;
544                 }
545                 attr->attr.name = "dev";
546                 attr->attr.mode = S_IRUGO;
547                 attr->attr.owner = parent_class->owner;
548                 attr->show = show_dev;
549                 class_device_create_file(class_dev, attr);
550                 class_dev->devt_attr = attr;
551         }
552
553         class_device_add_attrs(class_dev);
554         if (class_dev->dev) {
555                 class_name = make_class_name(class_dev);
556                 sysfs_create_link(&class_dev->kobj,
557                                   &class_dev->dev->kobj, "device");
558                 sysfs_create_link(&class_dev->dev->kobj, &class_dev->kobj,
559                                   class_name);
560         }
561
562         kobject_hotplug(&class_dev->kobj, KOBJ_ADD);
563
564         /* notify any interfaces this device is now here */
565         if (parent_class) {
566                 down(&parent_class->sem);
567                 list_add_tail(&class_dev->node, &parent_class->children);
568                 list_for_each_entry(class_intf, &parent_class->interfaces, node)
569                         if (class_intf->add)
570                                 class_intf->add(class_dev, class_intf);
571                 up(&parent_class->sem);
572         }
573
574  register_done:
575         if (error) {
576                 class_put(parent_class);
577                 class_device_put(parent_class_dev);
578         }
579         class_device_put(class_dev);
580         kfree(class_name);
581         return error;
582 }
583
584 int class_device_register(struct class_device *class_dev)
585 {
586         class_device_initialize(class_dev);
587         return class_device_add(class_dev);
588 }
589
590 /**
591  * class_device_create - creates a class device and registers it with sysfs
592  * @cs: pointer to the struct class that this device should be registered to.
593  * @parent: pointer to the parent struct class_device of this new device, if any.
594  * @dev: the dev_t for the char device to be added.
595  * @device: a pointer to a struct device that is assiociated with this class device.
596  * @fmt: string for the class device's name
597  *
598  * This function can be used by char device classes.  A struct
599  * class_device will be created in sysfs, registered to the specified
600  * class.
601  * A "dev" file will be created, showing the dev_t for the device, if
602  * the dev_t is not 0,0.
603  * If a pointer to a parent struct class_device is passed in, the newly
604  * created struct class_device will be a child of that device in sysfs.
605  * The pointer to the struct class_device will be returned from the
606  * call.  Any further sysfs files that might be required can be created
607  * using this pointer.
608  *
609  * Note: the struct class passed to this function must have previously
610  * been created with a call to class_create().
611  */
612 struct class_device *class_device_create(struct class *cls,
613                                          struct class_device *parent,
614                                          dev_t devt,
615                                          struct device *device, char *fmt, ...)
616 {
617         va_list args;
618         struct class_device *class_dev = NULL;
619         int retval = -ENODEV;
620
621         if (cls == NULL || IS_ERR(cls))
622                 goto error;
623
624         class_dev = kzalloc(sizeof(*class_dev), GFP_KERNEL);
625         if (!class_dev) {
626                 retval = -ENOMEM;
627                 goto error;
628         }
629
630         class_dev->devt = devt;
631         class_dev->dev = device;
632         class_dev->class = cls;
633         class_dev->parent = parent;
634         class_dev->release = class_device_create_release;
635         class_dev->hotplug = class_device_create_hotplug;
636
637         va_start(args, fmt);
638         vsnprintf(class_dev->class_id, BUS_ID_SIZE, fmt, args);
639         va_end(args);
640         retval = class_device_register(class_dev);
641         if (retval)
642                 goto error;
643
644         return class_dev;
645
646 error:
647         kfree(class_dev);
648         return ERR_PTR(retval);
649 }
650
651 void class_device_del(struct class_device *class_dev)
652 {
653         struct class *parent_class = class_dev->class;
654         struct class_device *parent_device = class_dev->parent;
655         struct class_interface *class_intf;
656         char *class_name = NULL;
657
658         if (parent_class) {
659                 down(&parent_class->sem);
660                 list_del_init(&class_dev->node);
661                 list_for_each_entry(class_intf, &parent_class->interfaces, node)
662                         if (class_intf->remove)
663                                 class_intf->remove(class_dev, class_intf);
664                 up(&parent_class->sem);
665         }
666
667         if (class_dev->dev) {
668                 class_name = make_class_name(class_dev);
669                 sysfs_remove_link(&class_dev->kobj, "device");
670                 sysfs_remove_link(&class_dev->dev->kobj, class_name);
671         }
672         class_device_remove_file(class_dev, &class_dev->uevent_attr);
673         if (class_dev->devt_attr)
674                 class_device_remove_file(class_dev, class_dev->devt_attr);
675         class_device_remove_attrs(class_dev);
676
677         kobject_hotplug(&class_dev->kobj, KOBJ_REMOVE);
678         kobject_del(&class_dev->kobj);
679
680         class_device_put(parent_device);
681         class_put(parent_class);
682         kfree(class_name);
683 }
684
685 void class_device_unregister(struct class_device *class_dev)
686 {
687         pr_debug("CLASS: Unregistering class device. ID = '%s'\n",
688                  class_dev->class_id);
689         class_device_del(class_dev);
690         class_device_put(class_dev);
691 }
692
693 /**
694  * class_device_destroy - removes a class device that was created with class_device_create()
695  * @cls: the pointer to the struct class that this device was registered * with.
696  * @dev: the dev_t of the device that was previously registered.
697  *
698  * This call unregisters and cleans up a class device that was created with a
699  * call to class_device_create()
700  */
701 void class_device_destroy(struct class *cls, dev_t devt)
702 {
703         struct class_device *class_dev = NULL;
704         struct class_device *class_dev_tmp;
705
706         down(&cls->sem);
707         list_for_each_entry(class_dev_tmp, &cls->children, node) {
708                 if (class_dev_tmp->devt == devt) {
709                         class_dev = class_dev_tmp;
710                         break;
711                 }
712         }
713         up(&cls->sem);
714
715         if (class_dev)
716                 class_device_unregister(class_dev);
717 }
718
719 int class_device_rename(struct class_device *class_dev, char *new_name)
720 {
721         int error = 0;
722         char *old_class_name = NULL, *new_class_name = NULL;
723
724         class_dev = class_device_get(class_dev);
725         if (!class_dev)
726                 return -EINVAL;
727
728         pr_debug("CLASS: renaming '%s' to '%s'\n", class_dev->class_id,
729                  new_name);
730
731         if (class_dev->dev)
732                 old_class_name = make_class_name(class_dev);
733
734         strlcpy(class_dev->class_id, new_name, KOBJ_NAME_LEN);
735
736         error = kobject_rename(&class_dev->kobj, new_name);
737
738         if (class_dev->dev) {
739                 new_class_name = make_class_name(class_dev);
740                 sysfs_create_link(&class_dev->dev->kobj, &class_dev->kobj,
741                                   new_class_name);
742                 sysfs_remove_link(&class_dev->dev->kobj, old_class_name);
743         }
744         class_device_put(class_dev);
745
746         kfree(old_class_name);
747         kfree(new_class_name);
748
749         return error;
750 }
751
752 struct class_device * class_device_get(struct class_device *class_dev)
753 {
754         if (class_dev)
755                 return to_class_dev(kobject_get(&class_dev->kobj));
756         return NULL;
757 }
758
759 void class_device_put(struct class_device *class_dev)
760 {
761         if (class_dev)
762                 kobject_put(&class_dev->kobj);
763 }
764
765
766 int class_interface_register(struct class_interface *class_intf)
767 {
768         struct class *parent;
769         struct class_device *class_dev;
770
771         if (!class_intf || !class_intf->class)
772                 return -ENODEV;
773
774         parent = class_get(class_intf->class);
775         if (!parent)
776                 return -EINVAL;
777
778         down(&parent->sem);
779         list_add_tail(&class_intf->node, &parent->interfaces);
780         if (class_intf->add) {
781                 list_for_each_entry(class_dev, &parent->children, node)
782                         class_intf->add(class_dev, class_intf);
783         }
784         up(&parent->sem);
785
786         return 0;
787 }
788
789 void class_interface_unregister(struct class_interface *class_intf)
790 {
791         struct class * parent = class_intf->class;
792         struct class_device *class_dev;
793
794         if (!parent)
795                 return;
796
797         down(&parent->sem);
798         list_del_init(&class_intf->node);
799         if (class_intf->remove) {
800                 list_for_each_entry(class_dev, &parent->children, node)
801                         class_intf->remove(class_dev, class_intf);
802         }
803         up(&parent->sem);
804
805         class_put(parent);
806 }
807
808
809
810 int __init classes_init(void)
811 {
812         int retval;
813
814         retval = subsystem_register(&class_subsys);
815         if (retval)
816                 return retval;
817
818         /* ick, this is ugly, the things we go through to keep from showing up
819          * in sysfs... */
820         subsystem_init(&class_obj_subsys);
821         if (!class_obj_subsys.kset.subsys)
822                         class_obj_subsys.kset.subsys = &class_obj_subsys;
823         return 0;
824 }
825
826 EXPORT_SYMBOL_GPL(class_create_file);
827 EXPORT_SYMBOL_GPL(class_remove_file);
828 EXPORT_SYMBOL_GPL(class_register);
829 EXPORT_SYMBOL_GPL(class_unregister);
830 EXPORT_SYMBOL_GPL(class_get);
831 EXPORT_SYMBOL_GPL(class_put);
832 EXPORT_SYMBOL_GPL(class_create);
833 EXPORT_SYMBOL_GPL(class_destroy);
834
835 EXPORT_SYMBOL_GPL(class_device_register);
836 EXPORT_SYMBOL_GPL(class_device_unregister);
837 EXPORT_SYMBOL_GPL(class_device_initialize);
838 EXPORT_SYMBOL_GPL(class_device_add);
839 EXPORT_SYMBOL_GPL(class_device_del);
840 EXPORT_SYMBOL_GPL(class_device_get);
841 EXPORT_SYMBOL_GPL(class_device_put);
842 EXPORT_SYMBOL_GPL(class_device_create);
843 EXPORT_SYMBOL_GPL(class_device_destroy);
844 EXPORT_SYMBOL_GPL(class_device_create_file);
845 EXPORT_SYMBOL_GPL(class_device_remove_file);
846 EXPORT_SYMBOL_GPL(class_device_create_bin_file);
847 EXPORT_SYMBOL_GPL(class_device_remove_bin_file);
848
849 EXPORT_SYMBOL_GPL(class_interface_register);
850 EXPORT_SYMBOL_GPL(class_interface_unregister);