[PATCH] Driver core: allow struct device to have a dev_t
[linux-2.6.git] / 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 static 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 static 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->devices);
146         INIT_LIST_HEAD(&cls->interfaces);
147         init_MUTEX(&cls->sem);
148         error = kobject_set_name(&cls->subsys.kset.kobj, "%s", cls->name);
149         if (error)
150                 return error;
151
152         subsys_set_kset(cls, class_subsys);
153
154         error = subsystem_register(&cls->subsys);
155         if (!error) {
156                 error = add_class_attrs(class_get(cls));
157                 class_put(cls);
158         }
159         return error;
160 }
161
162 void class_unregister(struct class * cls)
163 {
164         pr_debug("device class '%s': unregistering\n", cls->name);
165         remove_class_attrs(cls);
166         subsystem_unregister(&cls->subsys);
167 }
168
169 static void class_create_release(struct class *cls)
170 {
171         pr_debug("%s called for %s\n", __FUNCTION__, cls->name);
172         kfree(cls);
173 }
174
175 static void class_device_create_release(struct class_device *class_dev)
176 {
177         pr_debug("%s called for %s\n", __FUNCTION__, class_dev->class_id);
178         kfree(class_dev);
179 }
180
181 /* needed to allow these devices to have parent class devices */
182 static int class_device_create_uevent(struct class_device *class_dev,
183                                        char **envp, int num_envp,
184                                        char *buffer, int buffer_size)
185 {
186         pr_debug("%s called for %s\n", __FUNCTION__, class_dev->class_id);
187         return 0;
188 }
189
190 /**
191  * class_create - create a struct class structure
192  * @owner: pointer to the module that is to "own" this struct class
193  * @name: pointer to a string for the name of this class.
194  *
195  * This is used to create a struct class pointer that can then be used
196  * in calls to class_device_create().
197  *
198  * Note, the pointer created here is to be destroyed when finished by
199  * making a call to class_destroy().
200  */
201 struct class *class_create(struct module *owner, char *name)
202 {
203         struct class *cls;
204         int retval;
205
206         cls = kzalloc(sizeof(*cls), GFP_KERNEL);
207         if (!cls) {
208                 retval = -ENOMEM;
209                 goto error;
210         }
211
212         cls->name = name;
213         cls->owner = owner;
214         cls->class_release = class_create_release;
215         cls->release = class_device_create_release;
216
217         retval = class_register(cls);
218         if (retval)
219                 goto error;
220
221         return cls;
222
223 error:
224         kfree(cls);
225         return ERR_PTR(retval);
226 }
227
228 /**
229  * class_destroy - destroys a struct class structure
230  * @cs: pointer to the struct class that is to be destroyed
231  *
232  * Note, the pointer to be destroyed must have been created with a call
233  * to class_create().
234  */
235 void class_destroy(struct class *cls)
236 {
237         if ((cls == NULL) || (IS_ERR(cls)))
238                 return;
239
240         class_unregister(cls);
241 }
242
243 /* Class Device Stuff */
244
245 int class_device_create_file(struct class_device * class_dev,
246                              const struct class_device_attribute * attr)
247 {
248         int error = -EINVAL;
249         if (class_dev)
250                 error = sysfs_create_file(&class_dev->kobj, &attr->attr);
251         return error;
252 }
253
254 void class_device_remove_file(struct class_device * class_dev,
255                               const struct class_device_attribute * attr)
256 {
257         if (class_dev)
258                 sysfs_remove_file(&class_dev->kobj, &attr->attr);
259 }
260
261 int class_device_create_bin_file(struct class_device *class_dev,
262                                  struct bin_attribute *attr)
263 {
264         int error = -EINVAL;
265         if (class_dev)
266                 error = sysfs_create_bin_file(&class_dev->kobj, attr);
267         return error;
268 }
269
270 void class_device_remove_bin_file(struct class_device *class_dev,
271                                   struct bin_attribute *attr)
272 {
273         if (class_dev)
274                 sysfs_remove_bin_file(&class_dev->kobj, attr);
275 }
276
277 static ssize_t
278 class_device_attr_show(struct kobject * kobj, struct attribute * attr,
279                        char * buf)
280 {
281         struct class_device_attribute * class_dev_attr = to_class_dev_attr(attr);
282         struct class_device * cd = to_class_dev(kobj);
283         ssize_t ret = 0;
284
285         if (class_dev_attr->show)
286                 ret = class_dev_attr->show(cd, buf);
287         return ret;
288 }
289
290 static ssize_t
291 class_device_attr_store(struct kobject * kobj, struct attribute * attr,
292                         const char * buf, size_t count)
293 {
294         struct class_device_attribute * class_dev_attr = to_class_dev_attr(attr);
295         struct class_device * cd = to_class_dev(kobj);
296         ssize_t ret = 0;
297
298         if (class_dev_attr->store)
299                 ret = class_dev_attr->store(cd, buf, count);
300         return ret;
301 }
302
303 static struct sysfs_ops class_dev_sysfs_ops = {
304         .show   = class_device_attr_show,
305         .store  = class_device_attr_store,
306 };
307
308 static void class_dev_release(struct kobject * kobj)
309 {
310         struct class_device *cd = to_class_dev(kobj);
311         struct class * cls = cd->class;
312
313         pr_debug("device class '%s': release.\n", cd->class_id);
314
315         kfree(cd->devt_attr);
316         cd->devt_attr = NULL;
317
318         if (cd->release)
319                 cd->release(cd);
320         else if (cls->release)
321                 cls->release(cd);
322         else {
323                 printk(KERN_ERR "Class Device '%s' does not have a release() function, "
324                         "it is broken and must be fixed.\n",
325                         cd->class_id);
326                 WARN_ON(1);
327         }
328 }
329
330 static struct kobj_type ktype_class_device = {
331         .sysfs_ops      = &class_dev_sysfs_ops,
332         .release        = class_dev_release,
333 };
334
335 static int class_uevent_filter(struct kset *kset, struct kobject *kobj)
336 {
337         struct kobj_type *ktype = get_ktype(kobj);
338
339         if (ktype == &ktype_class_device) {
340                 struct class_device *class_dev = to_class_dev(kobj);
341                 if (class_dev->class)
342                         return 1;
343         }
344         return 0;
345 }
346
347 static const char *class_uevent_name(struct kset *kset, struct kobject *kobj)
348 {
349         struct class_device *class_dev = to_class_dev(kobj);
350
351         return class_dev->class->name;
352 }
353
354 static int class_uevent(struct kset *kset, struct kobject *kobj, char **envp,
355                          int num_envp, char *buffer, int buffer_size)
356 {
357         struct class_device *class_dev = to_class_dev(kobj);
358         int i = 0;
359         int length = 0;
360         int retval = 0;
361
362         pr_debug("%s - name = %s\n", __FUNCTION__, class_dev->class_id);
363
364         if (class_dev->dev) {
365                 /* add physical device, backing this device  */
366                 struct device *dev = class_dev->dev;
367                 char *path = kobject_get_path(&dev->kobj, GFP_KERNEL);
368
369                 add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
370                                &length, "PHYSDEVPATH=%s", path);
371                 kfree(path);
372
373                 if (dev->bus)
374                         add_uevent_var(envp, num_envp, &i,
375                                        buffer, buffer_size, &length,
376                                        "PHYSDEVBUS=%s", dev->bus->name);
377
378                 if (dev->driver)
379                         add_uevent_var(envp, num_envp, &i,
380                                        buffer, buffer_size, &length,
381                                        "PHYSDEVDRIVER=%s", dev->driver->name);
382         }
383
384         if (MAJOR(class_dev->devt)) {
385                 add_uevent_var(envp, num_envp, &i,
386                                buffer, buffer_size, &length,
387                                "MAJOR=%u", MAJOR(class_dev->devt));
388
389                 add_uevent_var(envp, num_envp, &i,
390                                buffer, buffer_size, &length,
391                                "MINOR=%u", MINOR(class_dev->devt));
392         }
393
394         /* terminate, set to next free slot, shrink available space */
395         envp[i] = NULL;
396         envp = &envp[i];
397         num_envp -= i;
398         buffer = &buffer[length];
399         buffer_size -= length;
400
401         if (class_dev->uevent) {
402                 /* have the class device specific function add its stuff */
403                 retval = class_dev->uevent(class_dev, envp, num_envp,
404                                             buffer, buffer_size);
405                 if (retval)
406                         pr_debug("class_dev->uevent() returned %d\n", retval);
407         } else if (class_dev->class->uevent) {
408                 /* have the class specific function add its stuff */
409                 retval = class_dev->class->uevent(class_dev, envp, num_envp,
410                                                    buffer, buffer_size);
411                 if (retval)
412                         pr_debug("class->uevent() returned %d\n", retval);
413         }
414
415         return retval;
416 }
417
418 static struct kset_uevent_ops class_uevent_ops = {
419         .filter =       class_uevent_filter,
420         .name =         class_uevent_name,
421         .uevent =       class_uevent,
422 };
423
424 static decl_subsys(class_obj, &ktype_class_device, &class_uevent_ops);
425
426
427 static int class_device_add_attrs(struct class_device * cd)
428 {
429         int i;
430         int error = 0;
431         struct class * cls = cd->class;
432
433         if (cls->class_dev_attrs) {
434                 for (i = 0; attr_name(cls->class_dev_attrs[i]); i++) {
435                         error = class_device_create_file(cd,
436                                                          &cls->class_dev_attrs[i]);
437                         if (error)
438                                 goto Err;
439                 }
440         }
441  Done:
442         return error;
443  Err:
444         while (--i >= 0)
445                 class_device_remove_file(cd,&cls->class_dev_attrs[i]);
446         goto Done;
447 }
448
449 static void class_device_remove_attrs(struct class_device * cd)
450 {
451         int i;
452         struct class * cls = cd->class;
453
454         if (cls->class_dev_attrs) {
455                 for (i = 0; attr_name(cls->class_dev_attrs[i]); i++)
456                         class_device_remove_file(cd,&cls->class_dev_attrs[i]);
457         }
458 }
459
460 static int class_device_add_groups(struct class_device * cd)
461 {
462         int i;
463         int error = 0;
464
465         if (cd->groups) {
466                 for (i = 0; cd->groups[i]; i++) {
467                         error = sysfs_create_group(&cd->kobj, cd->groups[i]);
468                         if (error) {
469                                 while (--i >= 0)
470                                         sysfs_remove_group(&cd->kobj, cd->groups[i]);
471                                 goto out;
472                         }
473                 }
474         }
475 out:
476         return error;
477 }
478
479 static void class_device_remove_groups(struct class_device * cd)
480 {
481         int i;
482         if (cd->groups) {
483                 for (i = 0; cd->groups[i]; i++) {
484                         sysfs_remove_group(&cd->kobj, cd->groups[i]);
485                 }
486         }
487 }
488
489 static ssize_t show_dev(struct class_device *class_dev, char *buf)
490 {
491         return print_dev_t(buf, class_dev->devt);
492 }
493
494 static ssize_t store_uevent(struct class_device *class_dev,
495                             const char *buf, size_t count)
496 {
497         kobject_uevent(&class_dev->kobj, KOBJ_ADD);
498         return count;
499 }
500
501 void class_device_initialize(struct class_device *class_dev)
502 {
503         kobj_set_kset_s(class_dev, class_obj_subsys);
504         kobject_init(&class_dev->kobj);
505         INIT_LIST_HEAD(&class_dev->node);
506 }
507
508 char *make_class_name(const char *name, struct kobject *kobj)
509 {
510         char *class_name;
511         int size;
512
513         size = strlen(name) + strlen(kobject_name(kobj)) + 2;
514
515         class_name = kmalloc(size, GFP_KERNEL);
516         if (!class_name)
517                 return ERR_PTR(-ENOMEM);
518
519         strcpy(class_name, name);
520         strcat(class_name, ":");
521         strcat(class_name, kobject_name(kobj));
522         return class_name;
523 }
524
525 int class_device_add(struct class_device *class_dev)
526 {
527         struct class *parent_class = NULL;
528         struct class_device *parent_class_dev = NULL;
529         struct class_interface *class_intf;
530         char *class_name = NULL;
531         int error = -EINVAL;
532
533         class_dev = class_device_get(class_dev);
534         if (!class_dev)
535                 return -EINVAL;
536
537         if (!strlen(class_dev->class_id))
538                 goto out1;
539
540         parent_class = class_get(class_dev->class);
541         if (!parent_class)
542                 goto out1;
543
544         parent_class_dev = class_device_get(class_dev->parent);
545
546         pr_debug("CLASS: registering class device: ID = '%s'\n",
547                  class_dev->class_id);
548
549         /* first, register with generic layer. */
550         error = kobject_set_name(&class_dev->kobj, "%s", class_dev->class_id);
551         if (error)
552                 goto out2;
553
554         if (parent_class_dev)
555                 class_dev->kobj.parent = &parent_class_dev->kobj;
556         else
557                 class_dev->kobj.parent = &parent_class->subsys.kset.kobj;
558
559         error = kobject_add(&class_dev->kobj);
560         if (error)
561                 goto out2;
562
563         /* add the needed attributes to this device */
564         class_dev->uevent_attr.attr.name = "uevent";
565         class_dev->uevent_attr.attr.mode = S_IWUSR;
566         class_dev->uevent_attr.attr.owner = parent_class->owner;
567         class_dev->uevent_attr.store = store_uevent;
568         error = class_device_create_file(class_dev, &class_dev->uevent_attr);
569         if (error)
570                 goto out3;
571
572         if (MAJOR(class_dev->devt)) {
573                 struct class_device_attribute *attr;
574                 attr = kzalloc(sizeof(*attr), GFP_KERNEL);
575                 if (!attr) {
576                         error = -ENOMEM;
577                         goto out4;
578                 }
579                 attr->attr.name = "dev";
580                 attr->attr.mode = S_IRUGO;
581                 attr->attr.owner = parent_class->owner;
582                 attr->show = show_dev;
583                 error = class_device_create_file(class_dev, attr);
584                 if (error) {
585                         kfree(attr);
586                         goto out4;
587                 }
588
589                 class_dev->devt_attr = attr;
590         }
591
592         error = class_device_add_attrs(class_dev);
593         if (error)
594                 goto out5;
595
596         if (class_dev->dev) {
597                 class_name = make_class_name(class_dev->class->name,
598                                              &class_dev->kobj);
599                 error = sysfs_create_link(&class_dev->kobj,
600                                           &class_dev->dev->kobj, "device");
601                 if (error)
602                         goto out6;
603                 error = sysfs_create_link(&class_dev->dev->kobj, &class_dev->kobj,
604                                           class_name);
605                 if (error)
606                         goto out7;
607         }
608
609         error = class_device_add_groups(class_dev);
610         if (error)
611                 goto out8;
612
613         kobject_uevent(&class_dev->kobj, KOBJ_ADD);
614
615         /* notify any interfaces this device is now here */
616         down(&parent_class->sem);
617         list_add_tail(&class_dev->node, &parent_class->children);
618         list_for_each_entry(class_intf, &parent_class->interfaces, node) {
619                 if (class_intf->add)
620                         class_intf->add(class_dev, class_intf);
621         }
622         up(&parent_class->sem);
623
624         goto out1;
625
626  out8:
627         if (class_dev->dev)
628                 sysfs_remove_link(&class_dev->kobj, class_name);
629  out7:
630         if (class_dev->dev)
631                 sysfs_remove_link(&class_dev->kobj, "device");
632  out6:
633         class_device_remove_attrs(class_dev);
634  out5:
635         if (class_dev->devt_attr)
636                 class_device_remove_file(class_dev, class_dev->devt_attr);
637  out4:
638         class_device_remove_file(class_dev, &class_dev->uevent_attr);
639  out3:
640         kobject_del(&class_dev->kobj);
641  out2:
642         if(parent_class_dev)
643                 class_device_put(parent_class_dev);
644         class_put(parent_class);
645  out1:
646         class_device_put(class_dev);
647         kfree(class_name);
648         return error;
649 }
650
651 int class_device_register(struct class_device *class_dev)
652 {
653         class_device_initialize(class_dev);
654         return class_device_add(class_dev);
655 }
656
657 /**
658  * class_device_create - creates a class device and registers it with sysfs
659  * @cs: pointer to the struct class that this device should be registered to.
660  * @parent: pointer to the parent struct class_device of this new device, if any.
661  * @dev: the dev_t for the char device to be added.
662  * @device: a pointer to a struct device that is assiociated with this class device.
663  * @fmt: string for the class device's name
664  *
665  * This function can be used by char device classes.  A struct
666  * class_device will be created in sysfs, registered to the specified
667  * class.
668  * A "dev" file will be created, showing the dev_t for the device, if
669  * the dev_t is not 0,0.
670  * If a pointer to a parent struct class_device is passed in, the newly
671  * created struct class_device will be a child of that device in sysfs.
672  * The pointer to the struct class_device will be returned from the
673  * call.  Any further sysfs files that might be required can be created
674  * using this pointer.
675  *
676  * Note: the struct class passed to this function must have previously
677  * been created with a call to class_create().
678  */
679 struct class_device *class_device_create(struct class *cls,
680                                          struct class_device *parent,
681                                          dev_t devt,
682                                          struct device *device, char *fmt, ...)
683 {
684         va_list args;
685         struct class_device *class_dev = NULL;
686         int retval = -ENODEV;
687
688         if (cls == NULL || IS_ERR(cls))
689                 goto error;
690
691         class_dev = kzalloc(sizeof(*class_dev), GFP_KERNEL);
692         if (!class_dev) {
693                 retval = -ENOMEM;
694                 goto error;
695         }
696
697         class_dev->devt = devt;
698         class_dev->dev = device;
699         class_dev->class = cls;
700         class_dev->parent = parent;
701         class_dev->release = class_device_create_release;
702         class_dev->uevent = class_device_create_uevent;
703
704         va_start(args, fmt);
705         vsnprintf(class_dev->class_id, BUS_ID_SIZE, fmt, args);
706         va_end(args);
707         retval = class_device_register(class_dev);
708         if (retval)
709                 goto error;
710
711         return class_dev;
712
713 error:
714         kfree(class_dev);
715         return ERR_PTR(retval);
716 }
717
718 void class_device_del(struct class_device *class_dev)
719 {
720         struct class *parent_class = class_dev->class;
721         struct class_device *parent_device = class_dev->parent;
722         struct class_interface *class_intf;
723         char *class_name = NULL;
724
725         if (parent_class) {
726                 down(&parent_class->sem);
727                 list_del_init(&class_dev->node);
728                 list_for_each_entry(class_intf, &parent_class->interfaces, node)
729                         if (class_intf->remove)
730                                 class_intf->remove(class_dev, class_intf);
731                 up(&parent_class->sem);
732         }
733
734         if (class_dev->dev) {
735                 class_name = make_class_name(class_dev->class->name,
736                                              &class_dev->kobj);
737                 sysfs_remove_link(&class_dev->kobj, "device");
738                 sysfs_remove_link(&class_dev->dev->kobj, class_name);
739         }
740         class_device_remove_file(class_dev, &class_dev->uevent_attr);
741         if (class_dev->devt_attr)
742                 class_device_remove_file(class_dev, class_dev->devt_attr);
743         class_device_remove_attrs(class_dev);
744         class_device_remove_groups(class_dev);
745
746         kobject_uevent(&class_dev->kobj, KOBJ_REMOVE);
747         kobject_del(&class_dev->kobj);
748
749         class_device_put(parent_device);
750         class_put(parent_class);
751         kfree(class_name);
752 }
753
754 void class_device_unregister(struct class_device *class_dev)
755 {
756         pr_debug("CLASS: Unregistering class device. ID = '%s'\n",
757                  class_dev->class_id);
758         class_device_del(class_dev);
759         class_device_put(class_dev);
760 }
761
762 /**
763  * class_device_destroy - removes a class device that was created with class_device_create()
764  * @cls: the pointer to the struct class that this device was registered * with.
765  * @dev: the dev_t of the device that was previously registered.
766  *
767  * This call unregisters and cleans up a class device that was created with a
768  * call to class_device_create()
769  */
770 void class_device_destroy(struct class *cls, dev_t devt)
771 {
772         struct class_device *class_dev = NULL;
773         struct class_device *class_dev_tmp;
774
775         down(&cls->sem);
776         list_for_each_entry(class_dev_tmp, &cls->children, node) {
777                 if (class_dev_tmp->devt == devt) {
778                         class_dev = class_dev_tmp;
779                         break;
780                 }
781         }
782         up(&cls->sem);
783
784         if (class_dev)
785                 class_device_unregister(class_dev);
786 }
787
788 int class_device_rename(struct class_device *class_dev, char *new_name)
789 {
790         int error = 0;
791         char *old_class_name = NULL, *new_class_name = NULL;
792
793         class_dev = class_device_get(class_dev);
794         if (!class_dev)
795                 return -EINVAL;
796
797         pr_debug("CLASS: renaming '%s' to '%s'\n", class_dev->class_id,
798                  new_name);
799
800         if (class_dev->dev)
801                 old_class_name = make_class_name(class_dev->class->name,
802                                                  &class_dev->kobj);
803
804         strlcpy(class_dev->class_id, new_name, KOBJ_NAME_LEN);
805
806         error = kobject_rename(&class_dev->kobj, new_name);
807
808         if (class_dev->dev) {
809                 new_class_name = make_class_name(class_dev->class->name,
810                                                  &class_dev->kobj);
811                 sysfs_create_link(&class_dev->dev->kobj, &class_dev->kobj,
812                                   new_class_name);
813                 sysfs_remove_link(&class_dev->dev->kobj, old_class_name);
814         }
815         class_device_put(class_dev);
816
817         kfree(old_class_name);
818         kfree(new_class_name);
819
820         return error;
821 }
822
823 struct class_device * class_device_get(struct class_device *class_dev)
824 {
825         if (class_dev)
826                 return to_class_dev(kobject_get(&class_dev->kobj));
827         return NULL;
828 }
829
830 void class_device_put(struct class_device *class_dev)
831 {
832         if (class_dev)
833                 kobject_put(&class_dev->kobj);
834 }
835
836
837 int class_interface_register(struct class_interface *class_intf)
838 {
839         struct class *parent;
840         struct class_device *class_dev;
841
842         if (!class_intf || !class_intf->class)
843                 return -ENODEV;
844
845         parent = class_get(class_intf->class);
846         if (!parent)
847                 return -EINVAL;
848
849         down(&parent->sem);
850         list_add_tail(&class_intf->node, &parent->interfaces);
851         if (class_intf->add) {
852                 list_for_each_entry(class_dev, &parent->children, node)
853                         class_intf->add(class_dev, class_intf);
854         }
855         up(&parent->sem);
856
857         return 0;
858 }
859
860 void class_interface_unregister(struct class_interface *class_intf)
861 {
862         struct class * parent = class_intf->class;
863         struct class_device *class_dev;
864
865         if (!parent)
866                 return;
867
868         down(&parent->sem);
869         list_del_init(&class_intf->node);
870         if (class_intf->remove) {
871                 list_for_each_entry(class_dev, &parent->children, node)
872                         class_intf->remove(class_dev, class_intf);
873         }
874         up(&parent->sem);
875
876         class_put(parent);
877 }
878
879
880
881 int __init classes_init(void)
882 {
883         int retval;
884
885         retval = subsystem_register(&class_subsys);
886         if (retval)
887                 return retval;
888
889         /* ick, this is ugly, the things we go through to keep from showing up
890          * in sysfs... */
891         subsystem_init(&class_obj_subsys);
892         if (!class_obj_subsys.kset.subsys)
893                         class_obj_subsys.kset.subsys = &class_obj_subsys;
894         return 0;
895 }
896
897 EXPORT_SYMBOL_GPL(class_create_file);
898 EXPORT_SYMBOL_GPL(class_remove_file);
899 EXPORT_SYMBOL_GPL(class_register);
900 EXPORT_SYMBOL_GPL(class_unregister);
901 EXPORT_SYMBOL_GPL(class_create);
902 EXPORT_SYMBOL_GPL(class_destroy);
903
904 EXPORT_SYMBOL_GPL(class_device_register);
905 EXPORT_SYMBOL_GPL(class_device_unregister);
906 EXPORT_SYMBOL_GPL(class_device_initialize);
907 EXPORT_SYMBOL_GPL(class_device_add);
908 EXPORT_SYMBOL_GPL(class_device_del);
909 EXPORT_SYMBOL_GPL(class_device_get);
910 EXPORT_SYMBOL_GPL(class_device_put);
911 EXPORT_SYMBOL_GPL(class_device_create);
912 EXPORT_SYMBOL_GPL(class_device_destroy);
913 EXPORT_SYMBOL_GPL(class_device_create_file);
914 EXPORT_SYMBOL_GPL(class_device_remove_file);
915 EXPORT_SYMBOL_GPL(class_device_create_bin_file);
916 EXPORT_SYMBOL_GPL(class_device_remove_bin_file);
917
918 EXPORT_SYMBOL_GPL(class_interface_register);
919 EXPORT_SYMBOL_GPL(class_interface_unregister);