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 "base.h"
  21
  22 #define to_class_attr(_attr) container_of(_attr, struct class_attribute, attr)
  23 #define to_class(obj) container_of(obj, struct class, subsys.kset.kobj)
  24
  25 static ssize_t
  26 class_attr_show(struct kobject * kobj, struct attribute * attr, char * buf)
  27 {
  28         struct class_attribute * class_attr = to_class_attr(attr);
  29         struct class * dc = to_class(kobj);
  30         ssize_t ret = -EIO;
  31
  32         if (class_attr->show)
  33                 ret = class_attr->show(dc, buf);
  34         return ret;
  35 }
  36
  37 static ssize_t
  38 class_attr_store(struct kobject * kobj, struct attribute * attr,
  39                  const char * buf, size_t count)
  40 {
  41         struct class_attribute * class_attr = to_class_attr(attr);
  42         struct class * dc = to_class(kobj);
  43         ssize_t ret = -EIO;
  44
  45         if (class_attr->store)
  46                 ret = class_attr->store(dc, buf, count);
  47         return ret;
  48 }
  49
  50 static void class_release(struct kobject * kobj)
  51 {
  52         struct class *class = to_class(kobj);
  53
  54         pr_debug("class '%s': release.\n", class->name);
  55
  56         if (class->class_release)
  57                 class->class_release(class);
  58         else
  59                 pr_debug("class '%s' does not have a release() function, "
  60                          "be careful\n", class->name);
  61 }
  62
  63 static struct sysfs_ops class_sysfs_ops = {
  64         .show   = class_attr_show,
  65         .store  = class_attr_store,
  66 };
  67
  68 static struct kobj_type ktype_class = {
  69         .sysfs_ops      = &class_sysfs_ops,
  70         .release        = class_release,
  71 };
  72
  73 /* Hotplug events for classes go to the class_obj subsys */
  74 static decl_subsys(class, &ktype_class, NULL);
  75
  76
  77 int class_create_file(struct class * cls, const struct class_attribute * attr)
  78 {
  79         int error;
  80         if (cls) {
  81                 error = sysfs_create_file(&cls->subsys.kset.kobj, &attr->attr);
  82         } else
  83                 error = -EINVAL;
  84         return error;
  85 }
  86
  87 void class_remove_file(struct class * cls, const struct class_attribute * attr)
  88 {
  89         if (cls)
  90                 sysfs_remove_file(&cls->subsys.kset.kobj, &attr->attr);
  91 }
  92
  93 struct class * class_get(struct class * cls)
  94 {
  95         if (cls)
  96                 return container_of(subsys_get(&cls->subsys), struct class, subsys);
  97         return NULL;
  98 }
  99
 100 void class_put(struct class * cls)
 101 {
 102         subsys_put(&cls->subsys);
 103 }
 104
 105
 106 static int add_class_attrs(struct class * cls)
 107 {
 108         int i;
 109         int error = 0;
 110
 111         if (cls->class_attrs) {
 112                 for (i = 0; attr_name(cls->class_attrs[i]); i++) {
 113                         error = class_create_file(cls,&cls->class_attrs[i]);
 114                         if (error)
 115                                 goto Err;
 116                 }
 117         }
 118  Done:
 119         return error;
 120  Err:
 121         while (--i >= 0)
 122                 class_remove_file(cls,&cls->class_attrs[i]);
 123         goto Done;
 124 }
 125
 126 static void remove_class_attrs(struct class * cls)
 127 {
 128         int i;
 129
 130         if (cls->class_attrs) {
 131                 for (i = 0; attr_name(cls->class_attrs[i]); i++)
 132                         class_remove_file(cls,&cls->class_attrs[i]);
 133         }
 134 }
 135
 136 int class_register(struct class * cls)
 137 {
 138         int error;
 139
 140         pr_debug("device class '%s': registering\n", cls->name);
 141
 142         INIT_LIST_HEAD(&cls->children);
 143         INIT_LIST_HEAD(&cls->interfaces);
 144         init_MUTEX(&cls->sem);
 145         error = kobject_set_name(&cls->subsys.kset.kobj, "%s", cls->name);
 146         if (error)
 147                 return error;
 148
 149         subsys_set_kset(cls, class_subsys);
 150
 151         error = subsystem_register(&cls->subsys);
 152         if (!error) {
 153                 error = add_class_attrs(class_get(cls));
 154                 class_put(cls);
 155         }
 156         return error;
 157 }
 158
 159 void class_unregister(struct class * cls)
 160 {
 161         pr_debug("device class '%s': unregistering\n", cls->name);
 162         remove_class_attrs(cls);
 163         subsystem_unregister(&cls->subsys);
 164 }
 165
 166 static void class_create_release(struct class *cls)
 167 {
 168         kfree(cls);
 169 }
 170
 171 static void class_device_create_release(struct class_device *class_dev)
 172 {
 173         kfree(class_dev);
 174 }
 175
 176 /**
 177  * class_create - create a struct class structure
 178  * @owner: pointer to the module that is to "own" this struct class
 179  * @name: pointer to a string for the name of this class.
 180  *
 181  * This is used to create a struct class pointer that can then be used
 182  * in calls to class_device_create().
 183  *
 184  * Note, the pointer created here is to be destroyed when finished by
 185  * making a call to class_destroy().
 186  */
 187 struct class *class_create(struct module *owner, char *name)
 188 {
 189         struct class *cls;
 190         int retval;
 191
 192         cls = kmalloc(sizeof(struct class), GFP_KERNEL);
 193         if (!cls) {
 194                 retval = -ENOMEM;
 195                 goto error;
 196         }
 197         memset(cls, 0x00, sizeof(struct class));
 198
 199         cls->name = name;
 200         cls->owner = owner;
 201         cls->class_release = class_create_release;
 202         cls->release = class_device_create_release;
 203
 204         retval = class_register(cls);
 205         if (retval)
 206                 goto error;
 207
 208         return cls;
 209
 210 error:
 211         kfree(cls);
 212         return ERR_PTR(retval);
 213 }
 214
 215 /**
 216  * class_destroy - destroys a struct class structure
 217  * @cs: pointer to the struct class that is to be destroyed
 218  *
 219  * Note, the pointer to be destroyed must have been created with a call
 220  * to class_create().
 221  */
 222 void class_destroy(struct class *cls)
 223 {
 224         if ((cls == NULL) || (IS_ERR(cls)))
 225                 return;
 226
 227         class_unregister(cls);
 228 }
 229
 230 /* Class Device Stuff */
 231
 232 int class_device_create_file(struct class_device * class_dev,
 233                              const struct class_device_attribute * attr)
 234 {
 235         int error = -EINVAL;
 236         if (class_dev)
 237                 error = sysfs_create_file(&class_dev->kobj, &attr->attr);
 238         return error;
 239 }
 240
 241 void class_device_remove_file(struct class_device * class_dev,
 242                               const struct class_device_attribute * attr)
 243 {
 244         if (class_dev)
 245                 sysfs_remove_file(&class_dev->kobj, &attr->attr);
 246 }
 247
 248 int class_device_create_bin_file(struct class_device *class_dev,
 249                                  struct bin_attribute *attr)
 250 {
 251         int error = -EINVAL;
 252         if (class_dev)
 253                 error = sysfs_create_bin_file(&class_dev->kobj, attr);
 254         return error;
 255 }
 256
 257 void class_device_remove_bin_file(struct class_device *class_dev,
 258                                   struct bin_attribute *attr)
 259 {
 260         if (class_dev)
 261                 sysfs_remove_bin_file(&class_dev->kobj, attr);
 262 }
 263
 264 static ssize_t
 265 class_device_attr_show(struct kobject * kobj, struct attribute * attr,
 266                        char * buf)
 267 {
 268         struct class_device_attribute * class_dev_attr = to_class_dev_attr(attr);
 269         struct class_device * cd = to_class_dev(kobj);
 270         ssize_t ret = 0;
 271
 272         if (class_dev_attr->show)
 273                 ret = class_dev_attr->show(cd, buf);
 274         return ret;
 275 }
 276
 277 static ssize_t
 278 class_device_attr_store(struct kobject * kobj, struct attribute * attr,
 279                         const char * buf, size_t count)
 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->store)
 286                 ret = class_dev_attr->store(cd, buf, count);
 287         return ret;
 288 }
 289
 290 static struct sysfs_ops class_dev_sysfs_ops = {
 291         .show   = class_device_attr_show,
 292         .store  = class_device_attr_store,
 293 };
 294
 295 static void class_dev_release(struct kobject * kobj)
 296 {
 297         struct class_device *cd = to_class_dev(kobj);
 298         struct class * cls = cd->class;
 299
 300         pr_debug("device class '%s': release.\n", cd->class_id);
 301
 302         if (cd->devt_attr) {
 303                 kfree(cd->devt_attr);
 304                 cd->devt_attr = NULL;
 305         }
 306
 307         if (cls->release)
 308                 cls->release(cd);
 309         else {
 310                 printk(KERN_ERR "Device class '%s' does not have a release() function, "
 311                         "it is broken and must be fixed.\n",
 312                         cd->class_id);
 313                 WARN_ON(1);
 314         }
 315 }
 316
 317 static struct kobj_type ktype_class_device = {
 318         .sysfs_ops      = &class_dev_sysfs_ops,
 319         .release        = class_dev_release,
 320 };
 321
 322 static int class_hotplug_filter(struct kset *kset, struct kobject *kobj)
 323 {
 324         struct kobj_type *ktype = get_ktype(kobj);
 325
 326         if (ktype == &ktype_class_device) {
 327                 struct class_device *class_dev = to_class_dev(kobj);
 328                 if (class_dev->class)
 329                         return 1;
 330         }
 331         return 0;
 332 }
 333
 334 static const char *class_hotplug_name(struct kset *kset, struct kobject *kobj)
 335 {
 336         struct class_device *class_dev = to_class_dev(kobj);
 337
 338         return class_dev->class->name;
 339 }
 340
 341 static int class_hotplug(struct kset *kset, struct kobject *kobj, char **envp,
 342                          int num_envp, char *buffer, int buffer_size)
 343 {
 344         struct class_device *class_dev = to_class_dev(kobj);
 345         int i = 0;
 346         int length = 0;
 347         int retval = 0;
 348
 349         pr_debug("%s - name = %s\n", __FUNCTION__, class_dev->class_id);
 350
 351         if (class_dev->dev) {
 352                 /* add physical device, backing this device  */
 353                 struct device *dev = class_dev->dev;
 354                 char *path = kobject_get_path(&dev->kobj, GFP_KERNEL);
 355
 356                 add_hotplug_env_var(envp, num_envp, &i, buffer, buffer_size,
 357                                     &length, "PHYSDEVPATH=%s", path);
 358                 kfree(path);
 359
 360                 if (dev->bus)
 361                         add_hotplug_env_var(envp, num_envp, &i,
 362                                             buffer, buffer_size, &length,
 363                                             "PHYSDEVBUS=%s", dev->bus->name);
 364
 365                 if (dev->driver)
 366                         add_hotplug_env_var(envp, num_envp, &i,
 367                                             buffer, buffer_size, &length,
 368                                             "PHYSDEVDRIVER=%s", dev->driver->name);
 369         }
 370
 371         if (MAJOR(class_dev->devt)) {
 372                 add_hotplug_env_var(envp, num_envp, &i,
 373                                     buffer, buffer_size, &length,
 374                                     "MAJOR=%u", MAJOR(class_dev->devt));
 375
 376                 add_hotplug_env_var(envp, num_envp, &i,
 377                                     buffer, buffer_size, &length,
 378                                     "MINOR=%u", MINOR(class_dev->devt));
 379         }
 380
 381         /* terminate, set to next free slot, shrink available space */
 382         envp[i] = NULL;
 383         envp = &envp[i];
 384         num_envp -= i;
 385         buffer = &buffer[length];
 386         buffer_size -= length;
 387
 388         if (class_dev->class->hotplug) {
 389                 /* have the bus specific function add its stuff */
 390                 retval = class_dev->class->hotplug (class_dev, envp, num_envp,
 391                                                     buffer, buffer_size);
 392                         if (retval) {
 393                         pr_debug ("%s - hotplug() returned %d\n",
 394                                   __FUNCTION__, retval);
 395                 }
 396         }
 397
 398         return retval;
 399 }
 400
 401 static struct kset_hotplug_ops class_hotplug_ops = {
 402         .filter =       class_hotplug_filter,
 403         .name =         class_hotplug_name,
 404         .hotplug =      class_hotplug,
 405 };
 406
 407 static decl_subsys(class_obj, &ktype_class_device, &class_hotplug_ops);
 408
 409
 410 static int class_device_add_attrs(struct class_device * cd)
 411 {
 412         int i;
 413         int error = 0;
 414         struct class * cls = cd->class;
 415
 416         if (cls->class_dev_attrs) {
 417                 for (i = 0; attr_name(cls->class_dev_attrs[i]); i++) {
 418                         error = class_device_create_file(cd,
 419                                                          &cls->class_dev_attrs[i]);
 420                         if (error)
 421                                 goto Err;
 422                 }
 423         }
 424  Done:
 425         return error;
 426  Err:
 427         while (--i >= 0)
 428                 class_device_remove_file(cd,&cls->class_dev_attrs[i]);
 429         goto Done;
 430 }
 431
 432 static void class_device_remove_attrs(struct class_device * cd)
 433 {
 434         int i;
 435         struct class * cls = cd->class;
 436
 437         if (cls->class_dev_attrs) {
 438                 for (i = 0; attr_name(cls->class_dev_attrs[i]); i++)
 439                         class_device_remove_file(cd,&cls->class_dev_attrs[i]);
 440         }
 441 }
 442
 443 static ssize_t show_dev(struct class_device *class_dev, char *buf)
 444 {
 445         return print_dev_t(buf, class_dev->devt);
 446 }
 447
 448 void class_device_initialize(struct class_device *class_dev)
 449 {
 450         kobj_set_kset_s(class_dev, class_obj_subsys);
 451         kobject_init(&class_dev->kobj);
 452         INIT_LIST_HEAD(&class_dev->node);
 453 }
 454
 455 int class_device_add(struct class_device *class_dev)
 456 {
 457         struct class * parent = NULL;
 458         struct class_interface * class_intf;
 459         int error;
 460
 461         class_dev = class_device_get(class_dev);
 462         if (!class_dev)
 463                 return -EINVAL;
 464
 465         if (!strlen(class_dev->class_id)) {
 466                 error = -EINVAL;
 467                 goto register_done;
 468         }
 469
 470         parent = class_get(class_dev->class);
 471
 472         pr_debug("CLASS: registering class device: ID = '%s'\n",
 473                  class_dev->class_id);
 474
 475         /* first, register with generic layer. */
 476         kobject_set_name(&class_dev->kobj, "%s", class_dev->class_id);
 477         if (parent)
 478                 class_dev->kobj.parent = &parent->subsys.kset.kobj;
 479
 480         if ((error = kobject_add(&class_dev->kobj)))
 481                 goto register_done;
 482
 483         /* add the needed attributes to this device */
 484         if (MAJOR(class_dev->devt)) {
 485                 struct class_device_attribute *attr;
 486                 attr = kmalloc(sizeof(*attr), GFP_KERNEL);
 487                 if (!attr) {
 488                         error = -ENOMEM;
 489                         kobject_del(&class_dev->kobj);
 490                         goto register_done;
 491                 }
 492                 memset(attr, sizeof(*attr), 0x00);
 493                 attr->attr.name = "dev";
 494                 attr->attr.mode = S_IRUGO;
 495                 attr->attr.owner = parent->owner;
 496                 attr->show = show_dev;
 497                 attr->store = NULL;
 498                 class_device_create_file(class_dev, attr);
 499                 class_dev->devt_attr = attr;
 500         }
 501
 502         class_device_add_attrs(class_dev);
 503         if (class_dev->dev)
 504                 sysfs_create_link(&class_dev->kobj,
 505                                   &class_dev->dev->kobj, "device");
 506
 507         /* notify any interfaces this device is now here */
 508         if (parent) {
 509                 down(&parent->sem);
 510                 list_add_tail(&class_dev->node, &parent->children);
 511                 list_for_each_entry(class_intf, &parent->interfaces, node)
 512                         if (class_intf->add)
 513                                 class_intf->add(class_dev);
 514                 up(&parent->sem);
 515         }
 516         kobject_hotplug(&class_dev->kobj, KOBJ_ADD);
 517
 518  register_done:
 519         if (error && parent)
 520                 class_put(parent);
 521         class_device_put(class_dev);
 522         return error;
 523 }
 524
 525 int class_device_register(struct class_device *class_dev)
 526 {
 527         class_device_initialize(class_dev);
 528         return class_device_add(class_dev);
 529 }
 530
 531 /**
 532  * class_device_create - creates a class device and registers it with sysfs
 533  * @cs: pointer to the struct class that this device should be registered to.
 534  * @dev: the dev_t for the char device to be added.
 535  * @device: a pointer to a struct device that is assiociated with this class device.
 536  * @fmt: string for the class device's name
 537  *
 538  * This function can be used by char device classes.  A struct
 539  * class_device will be created in sysfs, registered to the specified
 540  * class.  A "dev" file will be created, showing the dev_t for the
 541  * device.  The pointer to the struct class_device will be returned from
 542  * the call.  Any further sysfs files that might be required can be
 543  * created using this pointer.
 544  *
 545  * Note: the struct class passed to this function must have previously
 546  * been created with a call to class_create().
 547  */
 548 struct class_device *class_device_create(struct class *cls, dev_t devt,
 549                                          struct device *device, char *fmt, ...)
 550 {
 551         va_list args;
 552         struct class_device *class_dev = NULL;
 553         int retval = -ENODEV;
 554
 555         if (cls == NULL || IS_ERR(cls))
 556                 goto error;
 557
 558         class_dev = kmalloc(sizeof(struct class_device), GFP_KERNEL);
 559         if (!class_dev) {
 560                 retval = -ENOMEM;
 561                 goto error;
 562         }
 563         memset(class_dev, 0x00, sizeof(struct class_device));
 564
 565         class_dev->devt = devt;
 566         class_dev->dev = device;
 567         class_dev->class = cls;
 568
 569         va_start(args, fmt);
 570         vsnprintf(class_dev->class_id, BUS_ID_SIZE, fmt, args);
 571         va_end(args);
 572         retval = class_device_register(class_dev);
 573         if (retval)
 574                 goto error;
 575
 576         return class_dev;
 577
 578 error:
 579         kfree(class_dev);
 580         return ERR_PTR(retval);
 581 }
 582
 583 void class_device_del(struct class_device *class_dev)
 584 {
 585         struct class * parent = class_dev->class;
 586         struct class_interface * class_intf;
 587
 588         if (parent) {
 589                 down(&parent->sem);
 590                 list_del_init(&class_dev->node);
 591                 list_for_each_entry(class_intf, &parent->interfaces, node)
 592                         if (class_intf->remove)
 593                                 class_intf->remove(class_dev);
 594                 up(&parent->sem);
 595         }
 596
 597         if (class_dev->dev)
 598                 sysfs_remove_link(&class_dev->kobj, "device");
 599         if (class_dev->devt_attr)
 600                 class_device_remove_file(class_dev, class_dev->devt_attr);
 601         class_device_remove_attrs(class_dev);
 602
 603         kobject_hotplug(&class_dev->kobj, KOBJ_REMOVE);
 604         kobject_del(&class_dev->kobj);
 605
 606         if (parent)
 607                 class_put(parent);
 608 }
 609
 610 void class_device_unregister(struct class_device *class_dev)
 611 {
 612         pr_debug("CLASS: Unregistering class device. ID = '%s'\n",
 613                  class_dev->class_id);
 614         class_device_del(class_dev);
 615         class_device_put(class_dev);
 616 }
 617
 618 /**
 619  * class_device_destroy - removes a class device that was created with class_device_create()
 620  * @cls: the pointer to the struct class that this device was registered * with.
 621  * @dev: the dev_t of the device that was previously registered.
 622  *
 623  * This call unregisters and cleans up a class device that was created with a
 624  * call to class_device_create()
 625  */
 626 void class_device_destroy(struct class *cls, dev_t devt)
 627 {
 628         struct class_device *class_dev = NULL;
 629         struct class_device *class_dev_tmp;
 630
 631         down(&cls->sem);
 632         list_for_each_entry(class_dev_tmp, &cls->children, node) {
 633                 if (class_dev_tmp->devt == devt) {
 634                         class_dev = class_dev_tmp;
 635                         break;
 636                 }
 637         }
 638         up(&cls->sem);
 639
 640         if (class_dev)
 641                 class_device_unregister(class_dev);
 642 }
 643
 644 int class_device_rename(struct class_device *class_dev, char *new_name)
 645 {
 646         int error = 0;
 647
 648         class_dev = class_device_get(class_dev);
 649         if (!class_dev)
 650                 return -EINVAL;
 651
 652         pr_debug("CLASS: renaming '%s' to '%s'\n", class_dev->class_id,
 653                  new_name);
 654
 655         strlcpy(class_dev->class_id, new_name, KOBJ_NAME_LEN);
 656
 657         error = kobject_rename(&class_dev->kobj, new_name);
 658
 659         class_device_put(class_dev);
 660
 661         return error;
 662 }
 663
 664 struct class_device * class_device_get(struct class_device *class_dev)
 665 {
 666         if (class_dev)
 667                 return to_class_dev(kobject_get(&class_dev->kobj));
 668         return NULL;
 669 }
 670
 671 void class_device_put(struct class_device *class_dev)
 672 {
 673         kobject_put(&class_dev->kobj);
 674 }
 675
 676
 677 int class_interface_register(struct class_interface *class_intf)
 678 {
 679         struct class *parent;
 680         struct class_device *class_dev;
 681
 682         if (!class_intf || !class_intf->class)
 683                 return -ENODEV;
 684
 685         parent = class_get(class_intf->class);
 686         if (!parent)
 687                 return -EINVAL;
 688
 689         down(&parent->sem);
 690         list_add_tail(&class_intf->node, &parent->interfaces);
 691         if (class_intf->add) {
 692                 list_for_each_entry(class_dev, &parent->children, node)
 693                         class_intf->add(class_dev);
 694         }
 695         up(&parent->sem);
 696
 697         return 0;
 698 }
 699
 700 void class_interface_unregister(struct class_interface *class_intf)
 701 {
 702         struct class * parent = class_intf->class;
 703         struct class_device *class_dev;
 704
 705         if (!parent)
 706                 return;
 707
 708         down(&parent->sem);
 709         list_del_init(&class_intf->node);
 710         if (class_intf->remove) {
 711                 list_for_each_entry(class_dev, &parent->children, node)
 712                         class_intf->remove(class_dev);
 713         }
 714         up(&parent->sem);
 715
 716         class_put(parent);
 717 }
 718
 719
 720
 721 int __init classes_init(void)
 722 {
 723         int retval;
 724
 725         retval = subsystem_register(&class_subsys);
 726         if (retval)
 727                 return retval;
 728
 729         /* ick, this is ugly, the things we go through to keep from showing up
 730          * in sysfs... */
 731         subsystem_init(&class_obj_subsys);
 732         if (!class_obj_subsys.kset.subsys)
 733                         class_obj_subsys.kset.subsys = &class_obj_subsys;
 734         return 0;
 735 }
 736
 737 EXPORT_SYMBOL_GPL(class_create_file);
 738 EXPORT_SYMBOL_GPL(class_remove_file);
 739 EXPORT_SYMBOL_GPL(class_register);
 740 EXPORT_SYMBOL_GPL(class_unregister);
 741 EXPORT_SYMBOL_GPL(class_get);
 742 EXPORT_SYMBOL_GPL(class_put);
 743 EXPORT_SYMBOL_GPL(class_create);
 744 EXPORT_SYMBOL_GPL(class_destroy);
 745
 746 EXPORT_SYMBOL_GPL(class_device_register);
 747 EXPORT_SYMBOL_GPL(class_device_unregister);
 748 EXPORT_SYMBOL_GPL(class_device_initialize);
 749 EXPORT_SYMBOL_GPL(class_device_add);
 750 EXPORT_SYMBOL_GPL(class_device_del);
 751 EXPORT_SYMBOL_GPL(class_device_get);
 752 EXPORT_SYMBOL_GPL(class_device_put);
 753 EXPORT_SYMBOL_GPL(class_device_create);
 754 EXPORT_SYMBOL_GPL(class_device_destroy);
 755 EXPORT_SYMBOL_GPL(class_device_create_file);
 756 EXPORT_SYMBOL_GPL(class_device_remove_file);
 757 EXPORT_SYMBOL_GPL(class_device_create_bin_file);
 758 EXPORT_SYMBOL_GPL(class_device_remove_bin_file);
 759
 760 EXPORT_SYMBOL_GPL(class_interface_register);
 761 EXPORT_SYMBOL_GPL(class_interface_unregister);