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 "base.h"
19
20 #define to_class_attr(_attr) container_of(_attr, struct class_attribute, attr)
21 #define to_class(obj) container_of(obj, struct class, subsys.kset.kobj)
22
23 static ssize_t
24 class_attr_show(struct kobject * kobj, struct attribute * attr, char * buf)
25 {
26 struct class_attribute * class_attr = to_class_attr(attr);
27 struct class * dc = to_class(kobj);
28 ssize_t ret = 0;
29
30 if (class_attr->show)
31 ret = class_attr->show(dc, buf);
32 return ret;
33 }
34
35 static ssize_t
36 class_attr_store(struct kobject * kobj, struct attribute * attr,
37 const char * buf, size_t count)
38 {
39 struct class_attribute * class_attr = to_class_attr(attr);
40 struct class * dc = to_class(kobj);
41 ssize_t ret = 0;
42
43 if (class_attr->store)
44 ret = class_attr->store(dc, buf, count);
45 return ret;
46 }
47
48 static void class_release(struct kobject * kobj)
49 {
50 struct class *class = to_class(kobj);
51
52 pr_debug("class '%s': release.\n", class->name);
53
54 if (class->class_release)
55 class->class_release(class);
56 else
57 pr_debug("class '%s' does not have a release() function, "
58 "be careful\n", class->name);
59 }
60
61 static struct sysfs_ops class_sysfs_ops = {
62 .show = class_attr_show,
63 .store = class_attr_store,
64 };
65
66 static struct kobj_type ktype_class = {
67 .sysfs_ops = &class_sysfs_ops,
68 .release = class_release,
69 };
70
71 /* Hotplug events for classes go to the class_obj subsys */
72 static decl_subsys(class, &ktype_class, NULL);
73
74
75 int class_create_file(struct class * cls, const struct class_attribute * attr)
76 {
77 int error;
78 if (cls) {
79 error = sysfs_create_file(&cls->subsys.kset.kobj, &attr->attr);
80 } else
81 error = -EINVAL;
82 return error;
83 }
84
85 void class_remove_file(struct class * cls, const struct class_attribute * attr)
86 {
87 if (cls)
88 sysfs_remove_file(&cls->subsys.kset.kobj, &attr->attr);
89 }
90
91 struct class * class_get(struct class * cls)
92 {
93 if (cls)
94 return container_of(subsys_get(&cls->subsys), struct class, subsys);
95 return NULL;
96 }
97
98 void class_put(struct class * cls)
99 {
100 subsys_put(&cls->subsys);
101 }
102
103
104 static int add_class_attrs(struct class * cls)
105 {
106 int i;
107 int error = 0;
108
109 if (cls->class_attrs) {
110 for (i = 0; attr_name(cls->class_attrs[i]); i++) {
111 error = class_create_file(cls,&cls->class_attrs[i]);
112 if (error)
113 goto Err;
114 }
115 }
116 Done:
117 return error;
118 Err:
119 while (--i >= 0)
120 class_remove_file(cls,&cls->class_attrs[i]);
121 goto Done;
122 }
123
124 static void remove_class_attrs(struct class * cls)
125 {
126 int i;
127
128 if (cls->class_attrs) {
129 for (i = 0; attr_name(cls->class_attrs[i]); i++)
130 class_remove_file(cls,&cls->class_attrs[i]);
131 }
132 }
133
134 int class_register(struct class * cls)
135 {
136 int error;
137
138 pr_debug("device class '%s': registering\n", cls->name);
139
140 INIT_LIST_HEAD(&cls->children);
141 INIT_LIST_HEAD(&cls->interfaces);
142 error = kobject_set_name(&cls->subsys.kset.kobj, "%s", cls->name);
143 if (error)
144 return error;
145
146 subsys_set_kset(cls, class_subsys);
147
148 error = subsystem_register(&cls->subsys);
149 if (!error) {
150 error = add_class_attrs(class_get(cls));
151 class_put(cls);
152 }
153 return error;
154 }
155
156 void class_unregister(struct class * cls)
157 {
158 pr_debug("device class '%s': unregistering\n", cls->name);
159 remove_class_attrs(cls);
160 subsystem_unregister(&cls->subsys);
161 }
162
163
164 /* Class Device Stuff */
165
166 int class_device_create_file(struct class_device * class_dev,
167 const struct class_device_attribute * attr)
168 {
169 int error = -EINVAL;
170 if (class_dev)
171 error = sysfs_create_file(&class_dev->kobj, &attr->attr);
172 return error;
173 }
174
175 void class_device_remove_file(struct class_device * class_dev,
176 const struct class_device_attribute * attr)
177 {
178 if (class_dev)
179 sysfs_remove_file(&class_dev->kobj, &attr->attr);
180 }
181
182 int class_device_create_bin_file(struct class_device *class_dev,
183 struct bin_attribute *attr)
184 {
185 int error = -EINVAL;
186 if (class_dev)
187 error = sysfs_create_bin_file(&class_dev->kobj, attr);
188 return error;
189 }
190
191 void class_device_remove_bin_file(struct class_device *class_dev,
192 struct bin_attribute *attr)
193 {
194 if (class_dev)
195 sysfs_remove_bin_file(&class_dev->kobj, attr);
196 }
197
198 static int class_device_dev_link(struct class_device * class_dev)
199 {
200 if (class_dev->dev)
201 return sysfs_create_link(&class_dev->kobj,
202 &class_dev->dev->kobj, "device");
203 return 0;
204 }
205
206 static void class_device_dev_unlink(struct class_device * class_dev)
207 {
208 sysfs_remove_link(&class_dev->kobj, "device");
209 }
210
211 static int class_device_driver_link(struct class_device * class_dev)
212 {
213 if ((class_dev->dev) && (class_dev->dev->driver))
214 return sysfs_create_link(&class_dev->kobj,
215 &class_dev->dev->driver->kobj, "driver");
216 return 0;
217 }
218
219 static void class_device_driver_unlink(struct class_device * class_dev)
220 {
221 sysfs_remove_link(&class_dev->kobj, "driver");
222 }
223
224
225 static ssize_t
226 class_device_attr_show(struct kobject * kobj, struct attribute * attr,
227 char * buf)
228 {
229 struct class_device_attribute * class_dev_attr = to_class_dev_attr(attr);
230 struct class_device * cd = to_class_dev(kobj);
231 ssize_t ret = 0;
232
233 if (class_dev_attr->show)
234 ret = class_dev_attr->show(cd, buf);
235 return ret;
236 }
237
238 static ssize_t
239 class_device_attr_store(struct kobject * kobj, struct attribute * attr,
240 const char * buf, size_t count)
241 {
242 struct class_device_attribute * class_dev_attr = to_class_dev_attr(attr);
243 struct class_device * cd = to_class_dev(kobj);
244 ssize_t ret = 0;
245
246 if (class_dev_attr->store)
247 ret = class_dev_attr->store(cd, buf, count);
248 return ret;
249 }
250
251 static struct sysfs_ops class_dev_sysfs_ops = {
252 .show = class_device_attr_show,
253 .store = class_device_attr_store,
254 };
255
256 static void class_dev_release(struct kobject * kobj)
257 {
258 struct class_device *cd = to_class_dev(kobj);
259 struct class * cls = cd->class;
260
261 pr_debug("device class '%s': release.\n", cd->class_id);
262
263 if (cls->release)
264 cls->release(cd);
265 else {
266 printk(KERN_ERR "Device class '%s' does not have a release() function, "
267 "it is broken and must be fixed.\n",
268 cd->class_id);
269 WARN_ON(1);
270 }
271 }
272
273 static struct kobj_type ktype_class_device = {
274 .sysfs_ops = &class_dev_sysfs_ops,
275 .release = class_dev_release,
276 };
277
278 static int class_hotplug_filter(struct kset *kset, struct kobject *kobj)
279 {
280 struct kobj_type *ktype = get_ktype(kobj);
281
282 if (ktype == &ktype_class_device) {
283 struct class_device *class_dev = to_class_dev(kobj);
284 if (class_dev->class)
285 return 1;
286 }
287 return 0;
288 }
289
290 static char *class_hotplug_name(struct kset *kset, struct kobject *kobj)
291 {
292 struct class_device *class_dev = to_class_dev(kobj);
293
294 return class_dev->class->name;
295 }
296
297 static int class_hotplug(struct kset *kset, struct kobject *kobj, char **envp,
298 int num_envp, char *buffer, int buffer_size)
299 {
300 struct class_device *class_dev = to_class_dev(kobj);
301 int retval = 0;
302 int i = 0;
303 int length = 0;
304
305 pr_debug("%s - name = %s\n", __FUNCTION__, class_dev->class_id);
306
307 if (class_dev->dev) {
308 /* add physical device, backing this device */
309 struct device *dev = class_dev->dev;
310 char *path = kobject_get_path(&dev->kobj, GFP_KERNEL);
311
312 add_hotplug_env_var(envp, num_envp, &i, buffer, buffer_size,
313 &length, "PHYSDEVPATH=%s", path);
314 kfree(path);
315
316 /* add bus name of physical device */
317 if (dev->bus)
318 add_hotplug_env_var(envp, num_envp, &i,
319 buffer, buffer_size, &length,
320 "PHYSDEVBUS=%s", dev->bus->name);
321
322 /* add driver name of physical device */
323 if (dev->driver)
324 add_hotplug_env_var(envp, num_envp, &i,
325 buffer, buffer_size, &length,
326 "PHYSDEVDRIVER=%s", dev->driver->name);
327
328 /* terminate, set to next free slot, shrink available space */
329 envp[i] = NULL;
330 envp = &envp[i];
331 num_envp -= i;
332 buffer = &buffer[length];
333 buffer_size -= length;
334 }
335
336 if (class_dev->class->hotplug) {
337 /* have the bus specific function add its stuff */
338 retval = class_dev->class->hotplug (class_dev, envp, num_envp,
339 buffer, buffer_size);
340 if (retval) {
341 pr_debug ("%s - hotplug() returned %d\n",
342 __FUNCTION__, retval);
343 }
344 }
345
346 return retval;
347 }
348
349 static struct kset_hotplug_ops class_hotplug_ops = {
350 .filter = class_hotplug_filter,
351 .name = class_hotplug_name,
352 .hotplug = class_hotplug,
353 };
354
355 static decl_subsys(class_obj, &ktype_class_device, &class_hotplug_ops);
356
357
358 static int class_device_add_attrs(struct class_device * cd)
359 {
360 int i;
361 int error = 0;
362 struct class * cls = cd->class;
363
364 if (cls->class_dev_attrs) {
365 for (i = 0; attr_name(cls->class_dev_attrs[i]); i++) {
366 error = class_device_create_file(cd,
367 &cls->class_dev_attrs[i]);
368 if (error)
369 goto Err;
370 }
371 }
372 Done:
373 return error;
374 Err:
375 while (--i >= 0)
376 class_device_remove_file(cd,&cls->class_dev_attrs[i]);
377 goto Done;
378 }
379
380 static void class_device_remove_attrs(struct class_device * cd)
381 {
382 int i;
383 struct class * cls = cd->class;
384
385 if (cls->class_dev_attrs) {
386 for (i = 0; attr_name(cls->class_dev_attrs[i]); i++)
387 class_device_remove_file(cd,&cls->class_dev_attrs[i]);
388 }
389 }
390
391 void class_device_initialize(struct class_device *class_dev)
392 {
393 kobj_set_kset_s(class_dev, class_obj_subsys);
394 kobject_init(&class_dev->kobj);
395 INIT_LIST_HEAD(&class_dev->node);
396 }
397
398 int class_device_add(struct class_device *class_dev)
399 {
400 struct class * parent = NULL;
401 struct class_interface * class_intf;
402 int error;
403
404 class_dev = class_device_get(class_dev);
405 if (!class_dev)
406 return -EINVAL;
407
408 if (!strlen(class_dev->class_id)) {
409 error = -EINVAL;
410 goto register_done;
411 }
412
413 parent = class_get(class_dev->class);
414
415 pr_debug("CLASS: registering class device: ID = '%s'\n",
416 class_dev->class_id);
417
418 /* first, register with generic layer. */
419 kobject_set_name(&class_dev->kobj, "%s", class_dev->class_id);
420 if (parent)
421 class_dev->kobj.parent = &parent->subsys.kset.kobj;
422
423 if ((error = kobject_add(&class_dev->kobj)))
424 goto register_done;
425
426 /* now take care of our own registration */
427 if (parent) {
428 down_write(&parent->subsys.rwsem);
429 list_add_tail(&class_dev->node, &parent->children);
430 list_for_each_entry(class_intf, &parent->interfaces, node)
431 if (class_intf->add)
432 class_intf->add(class_dev);
433 up_write(&parent->subsys.rwsem);
434 }
435 class_device_add_attrs(class_dev);
436 class_device_dev_link(class_dev);
437 class_device_driver_link(class_dev);
438
439 register_done:
440 if (error && parent)
441 class_put(parent);
442 class_device_put(class_dev);
443 return error;
444 }
445
446 int class_device_register(struct class_device *class_dev)
447 {
448 class_device_initialize(class_dev);
449 return class_device_add(class_dev);
450 }
451
452 void class_device_del(struct class_device *class_dev)
453 {
454 struct class * parent = class_dev->class;
455 struct class_interface * class_intf;
456
457 if (parent) {
458 down_write(&parent->subsys.rwsem);
459 list_del_init(&class_dev->node);
460 list_for_each_entry(class_intf, &parent->interfaces, node)
461 if (class_intf->remove)
462 class_intf->remove(class_dev);
463 up_write(&parent->subsys.rwsem);
464 }
465
466 class_device_dev_unlink(class_dev);
467 class_device_driver_unlink(class_dev);
468 class_device_remove_attrs(class_dev);
469
470 kobject_del(&class_dev->kobj);
471
472 if (parent)
473 class_put(parent);
474 }
475
476 void class_device_unregister(struct class_device *class_dev)
477 {
478 pr_debug("CLASS: Unregistering class device. ID = '%s'\n",
479 class_dev->class_id);
480 class_device_del(class_dev);
481 class_device_put(class_dev);
482 }
483
484 int class_device_rename(struct class_device *class_dev, char *new_name)
485 {
486 int error = 0;
487
488 class_dev = class_device_get(class_dev);
489 if (!class_dev)
490 return -EINVAL;
491
492 pr_debug("CLASS: renaming '%s' to '%s'\n", class_dev->class_id,
493 new_name);
494
495 strlcpy(class_dev->class_id, new_name, KOBJ_NAME_LEN);
496
497 error = kobject_rename(&class_dev->kobj, new_name);
498
499 class_device_put(class_dev);
500
501 return error;
502 }
503
504 struct class_device * class_device_get(struct class_device *class_dev)
505 {
506 if (class_dev)
507 return to_class_dev(kobject_get(&class_dev->kobj));
508 return NULL;
509 }
510
511 void class_device_put(struct class_device *class_dev)
512 {
513 kobject_put(&class_dev->kobj);
514 }
515
516
517 int class_interface_register(struct class_interface *class_intf)
518 {
519 struct class * parent;
520 struct class_device * class_dev;
521
522 if (!class_intf || !class_intf->class)
523 return -ENODEV;
524
525 parent = class_get(class_intf->class);
526 if (!parent)
527 return -EINVAL;
528
529 down_write(&parent->subsys.rwsem);
530 list_add_tail(&class_intf->node, &parent->interfaces);
531
532 if (class_intf->add) {
533 list_for_each_entry(class_dev, &parent->children, node)
534 class_intf->add(class_dev);
535 }
536 up_write(&parent->subsys.rwsem);
537
538 return 0;
539 }
540
541 void class_interface_unregister(struct class_interface *class_intf)
542 {
543 struct class * parent = class_intf->class;
544 struct class_device *class_dev;
545
546 if (!parent)
547 return;
548
549 down_write(&parent->subsys.rwsem);
550 list_del_init(&class_intf->node);
551
552 if (class_intf->remove) {
553 list_for_each_entry(class_dev, &parent->children, node)
554 class_intf->remove(class_dev);
555 }
556 up_write(&parent->subsys.rwsem);
557
558 class_put(parent);
559 }
560
561
562
563 int __init classes_init(void)
564 {
565 int retval;
566
567 retval = subsystem_register(&class_subsys);
568 if (retval)
569 return retval;
570
571 /* ick, this is ugly, the things we go through to keep from showing up
572 * in sysfs... */
573 subsystem_init(&class_obj_subsys);
574 if (!class_obj_subsys.kset.subsys)
575 class_obj_subsys.kset.subsys = &class_obj_subsys;
576 return 0;
577 }
578
579 EXPORT_SYMBOL_GPL(class_create_file);
580 EXPORT_SYMBOL_GPL(class_remove_file);
581 EXPORT_SYMBOL_GPL(class_register);
582 EXPORT_SYMBOL_GPL(class_unregister);
583 EXPORT_SYMBOL_GPL(class_get);
584 EXPORT_SYMBOL_GPL(class_put);
585
586 EXPORT_SYMBOL_GPL(class_device_register);
587 EXPORT_SYMBOL_GPL(class_device_unregister);
588 EXPORT_SYMBOL_GPL(class_device_initialize);
589 EXPORT_SYMBOL_GPL(class_device_add);
590 EXPORT_SYMBOL_GPL(class_device_del);
591 EXPORT_SYMBOL_GPL(class_device_get);
592 EXPORT_SYMBOL_GPL(class_device_put);
593 EXPORT_SYMBOL_GPL(class_device_create_file);
594 EXPORT_SYMBOL_GPL(class_device_remove_file);
595 EXPORT_SYMBOL_GPL(class_device_create_bin_file);
596 EXPORT_SYMBOL_GPL(class_device_remove_bin_file);
597
598 EXPORT_SYMBOL_GPL(class_interface_register);
599 EXPORT_SYMBOL_GPL(class_interface_unregister);
600
|
This page was automatically generated by the
LXR engine.
|