drivers/acpi/scan.c

   1 /*
   2  * scan.c - support for transforming the ACPI namespace into individual objects
   3  */
   4
   5 #include <linux/module.h>
   6 #include <linux/init.h>
   7 #include <linux/slab.h>
   8 #include <linux/kernel.h>
   9 #include <linux/acpi.h>
  10 #include <linux/signal.h>
  11 #include <linux/kthread.h>
  12 #include <linux/dmi.h>
  13 #include <linux/nls.h>
  14
  15 #include <asm/pgtable.h>
  16
  17 #include "internal.h"
  18
  19 #define _COMPONENT              ACPI_BUS_COMPONENT
  20 ACPI_MODULE_NAME("scan");
  21 extern struct acpi_device *acpi_root;
  22
  23 #define ACPI_BUS_CLASS                  "system_bus"
  24 #define ACPI_BUS_HID                    "LNXSYBUS"
  25 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  26
  27 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
  28
  29 #define INVALID_ACPI_HANDLE     ((acpi_handle)empty_zero_page)
  30
  31 /*
  32  * If set, devices will be hot-removed even if they cannot be put offline
  33  * gracefully (from the kernel's standpoint).
  34  */
  35 bool acpi_force_hot_remove;
  36
  37 static const char *dummy_hid = "device";
  38
  39 static LIST_HEAD(acpi_bus_id_list);
  40 static DEFINE_MUTEX(acpi_scan_lock);
  41 static LIST_HEAD(acpi_scan_handlers_list);
  42 DEFINE_MUTEX(acpi_device_lock);
  43 LIST_HEAD(acpi_wakeup_device_list);
  44 static DEFINE_MUTEX(acpi_hp_context_lock);
  45
  46 struct acpi_device_bus_id{
  47         char bus_id[15];
  48         unsigned int instance_no;
  49         struct list_head node;
  50 };
  51
  52 void acpi_scan_lock_acquire(void)
  53 {
  54         mutex_lock(&acpi_scan_lock);
  55 }
  56 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
  57
  58 void acpi_scan_lock_release(void)
  59 {
  60         mutex_unlock(&acpi_scan_lock);
  61 }
  62 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
  63
  64 void acpi_lock_hp_context(void)
  65 {
  66         mutex_lock(&acpi_hp_context_lock);
  67 }
  68
  69 void acpi_unlock_hp_context(void)
  70 {
  71         mutex_unlock(&acpi_hp_context_lock);
  72 }
  73
  74 void acpi_initialize_hp_context(struct acpi_device *adev,
  75                                 struct acpi_hotplug_context *hp,
  76                                 int (*notify)(struct acpi_device *, u32),
  77                                 void (*uevent)(struct acpi_device *, u32))
  78 {
  79         acpi_lock_hp_context();
  80         hp->notify = notify;
  81         hp->uevent = uevent;
  82         acpi_set_hp_context(adev, hp);
  83         acpi_unlock_hp_context();
  84 }
  85 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
  86
  87 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
  88 {
  89         if (!handler)
  90                 return -EINVAL;
  91
  92         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
  93         return 0;
  94 }
  95
  96 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
  97                                        const char *hotplug_profile_name)
  98 {
  99         int error;
 100
 101         error = acpi_scan_add_handler(handler);
 102         if (error)
 103                 return error;
 104
 105         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
 106         return 0;
 107 }
 108
 109 /*
 110  * Creates hid/cid(s) string needed for modalias and uevent
 111  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
 112  * char *modalias: "acpi:IBM0001:ACPI0001"
 113  * Return: 0: no _HID and no _CID
 114  *         -EINVAL: output error
 115  *         -ENOMEM: output is truncated
 116 */
 117 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
 118                            int size)
 119 {
 120         int len;
 121         int count;
 122         struct acpi_hardware_id *id;
 123
 124         if (list_empty(&acpi_dev->pnp.ids))
 125                 return 0;
 126
 127         len = snprintf(modalias, size, "acpi:");
 128         size -= len;
 129
 130         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
 131                 count = snprintf(&modalias[len], size, "%s:", id->id);
 132                 if (count < 0)
 133                         return -EINVAL;
 134                 if (count >= size)
 135                         return -ENOMEM;
 136                 len += count;
 137                 size -= count;
 138         }
 139
 140         modalias[len] = '\0';
 141         return len;
 142 }
 143
 144 /*
 145  * Creates uevent modalias field for ACPI enumerated devices.
 146  * Because the other buses does not support ACPI HIDs & CIDs.
 147  * e.g. for a device with hid:IBM0001 and cid:ACPI0001 you get:
 148  * "acpi:IBM0001:ACPI0001"
 149  */
 150 int acpi_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
 151 {
 152         struct acpi_device *acpi_dev;
 153         int len;
 154
 155         acpi_dev = ACPI_COMPANION(dev);
 156         if (!acpi_dev)
 157                 return -ENODEV;
 158
 159         /* Fall back to bus specific way of modalias exporting */
 160         if (list_empty(&acpi_dev->pnp.ids))
 161                 return -ENODEV;
 162
 163         if (add_uevent_var(env, "MODALIAS="))
 164                 return -ENOMEM;
 165         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 166                                 sizeof(env->buf) - env->buflen);
 167         if (len <= 0)
 168                 return len;
 169         env->buflen += len;
 170         return 0;
 171 }
 172 EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias);
 173
 174 /*
 175  * Creates modalias sysfs attribute for ACPI enumerated devices.
 176  * Because the other buses does not support ACPI HIDs & CIDs.
 177  * e.g. for a device with hid:IBM0001 and cid:ACPI0001 you get:
 178  * "acpi:IBM0001:ACPI0001"
 179  */
 180 int acpi_device_modalias(struct device *dev, char *buf, int size)
 181 {
 182         struct acpi_device *acpi_dev;
 183         int len;
 184
 185         acpi_dev = ACPI_COMPANION(dev);
 186         if (!acpi_dev)
 187                 return -ENODEV;
 188
 189         /* Fall back to bus specific way of modalias exporting */
 190         if (list_empty(&acpi_dev->pnp.ids))
 191                 return -ENODEV;
 192
 193         len = create_modalias(acpi_dev, buf, size -1);
 194         if (len <= 0)
 195                 return len;
 196         buf[len++] = '\n';
 197         return len;
 198 }
 199 EXPORT_SYMBOL_GPL(acpi_device_modalias);
 200
 201 static ssize_t
 202 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
 203         struct acpi_device *acpi_dev = to_acpi_device(dev);
 204         int len;
 205
 206         len = create_modalias(acpi_dev, buf, 1024);
 207         if (len <= 0)
 208                 return len;
 209         buf[len++] = '\n';
 210         return len;
 211 }
 212 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
 213
 214 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
 215 {
 216         struct acpi_device_physical_node *pn;
 217         bool offline = true;
 218
 219         mutex_lock(&adev->physical_node_lock);
 220
 221         list_for_each_entry(pn, &adev->physical_node_list, node)
 222                 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
 223                         if (uevent)
 224                                 kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
 225
 226                         offline = false;
 227                         break;
 228                 }
 229
 230         mutex_unlock(&adev->physical_node_lock);
 231         return offline;
 232 }
 233
 234 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
 235                                     void **ret_p)
 236 {
 237         struct acpi_device *device = NULL;
 238         struct acpi_device_physical_node *pn;
 239         bool second_pass = (bool)data;
 240         acpi_status status = AE_OK;
 241
 242         if (acpi_bus_get_device(handle, &device))
 243                 return AE_OK;
 244
 245         if (device->handler && !device->handler->hotplug.enabled) {
 246                 *ret_p = &device->dev;
 247                 return AE_SUPPORT;
 248         }
 249
 250         mutex_lock(&device->physical_node_lock);
 251
 252         list_for_each_entry(pn, &device->physical_node_list, node) {
 253                 int ret;
 254
 255                 if (second_pass) {
 256                         /* Skip devices offlined by the first pass. */
 257                         if (pn->put_online)
 258                                 continue;
 259                 } else {
 260                         pn->put_online = false;
 261                 }
 262                 ret = device_offline(pn->dev);
 263                 if (acpi_force_hot_remove)
 264                         continue;
 265
 266                 if (ret >= 0) {
 267                         pn->put_online = !ret;
 268                 } else {
 269                         *ret_p = pn->dev;
 270                         if (second_pass) {
 271                                 status = AE_ERROR;
 272                                 break;
 273                         }
 274                 }
 275         }
 276
 277         mutex_unlock(&device->physical_node_lock);
 278
 279         return status;
 280 }
 281
 282 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
 283                                    void **ret_p)
 284 {
 285         struct acpi_device *device = NULL;
 286         struct acpi_device_physical_node *pn;
 287
 288         if (acpi_bus_get_device(handle, &device))
 289                 return AE_OK;
 290
 291         mutex_lock(&device->physical_node_lock);
 292
 293         list_for_each_entry(pn, &device->physical_node_list, node)
 294                 if (pn->put_online) {
 295                         device_online(pn->dev);
 296                         pn->put_online = false;
 297                 }
 298
 299         mutex_unlock(&device->physical_node_lock);
 300
 301         return AE_OK;
 302 }
 303
 304 static int acpi_scan_try_to_offline(struct acpi_device *device)
 305 {
 306         acpi_handle handle = device->handle;
 307         struct device *errdev = NULL;
 308         acpi_status status;
 309
 310         /*
 311          * Carry out two passes here and ignore errors in the first pass,
 312          * because if the devices in question are memory blocks and
 313          * CONFIG_MEMCG is set, one of the blocks may hold data structures
 314          * that the other blocks depend on, but it is not known in advance which
 315          * block holds them.
 316          *
 317          * If the first pass is successful, the second one isn't needed, though.
 318          */
 319         status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 320                                      NULL, acpi_bus_offline, (void *)false,
 321                                      (void **)&errdev);
 322         if (status == AE_SUPPORT) {
 323                 dev_warn(errdev, "Offline disabled.\n");
 324                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 325                                     acpi_bus_online, NULL, NULL, NULL);
 326                 return -EPERM;
 327         }
 328         acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
 329         if (errdev) {
 330                 errdev = NULL;
 331                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 332                                     NULL, acpi_bus_offline, (void *)true,
 333                                     (void **)&errdev);
 334                 if (!errdev || acpi_force_hot_remove)
 335                         acpi_bus_offline(handle, 0, (void *)true,
 336                                          (void **)&errdev);
 337
 338                 if (errdev && !acpi_force_hot_remove) {
 339                         dev_warn(errdev, "Offline failed.\n");
 340                         acpi_bus_online(handle, 0, NULL, NULL);
 341                         acpi_walk_namespace(ACPI_TYPE_ANY, handle,
 342                                             ACPI_UINT32_MAX, acpi_bus_online,
 343                                             NULL, NULL, NULL);
 344                         return -EBUSY;
 345                 }
 346         }
 347         return 0;
 348 }
 349
 350 static int acpi_scan_hot_remove(struct acpi_device *device)
 351 {
 352         acpi_handle handle = device->handle;
 353         unsigned long long sta;
 354         acpi_status status;
 355
 356         if (device->handler && device->handler->hotplug.demand_offline
 357             && !acpi_force_hot_remove) {
 358                 if (!acpi_scan_is_offline(device, true))
 359                         return -EBUSY;
 360         } else {
 361                 int error = acpi_scan_try_to_offline(device);
 362                 if (error)
 363                         return error;
 364         }
 365
 366         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 367                 "Hot-removing device %s...\n", dev_name(&device->dev)));
 368
 369         acpi_bus_trim(device);
 370
 371         acpi_evaluate_lck(handle, 0);
 372         /*
 373          * TBD: _EJD support.
 374          */
 375         status = acpi_evaluate_ej0(handle);
 376         if (status == AE_NOT_FOUND)
 377                 return -ENODEV;
 378         else if (ACPI_FAILURE(status))
 379                 return -EIO;
 380
 381         /*
 382          * Verify if eject was indeed successful.  If not, log an error
 383          * message.  No need to call _OST since _EJ0 call was made OK.
 384          */
 385         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 386         if (ACPI_FAILURE(status)) {
 387                 acpi_handle_warn(handle,
 388                         "Status check after eject failed (0x%x)\n", status);
 389         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
 390                 acpi_handle_warn(handle,
 391                         "Eject incomplete - status 0x%llx\n", sta);
 392         }
 393
 394         return 0;
 395 }
 396
 397 static int acpi_scan_device_not_present(struct acpi_device *adev)
 398 {
 399         if (!acpi_device_enumerated(adev)) {
 400                 dev_warn(&adev->dev, "Still not present\n");
 401                 return -EALREADY;
 402         }
 403         acpi_bus_trim(adev);
 404         return 0;
 405 }
 406
 407 static int acpi_scan_device_check(struct acpi_device *adev)
 408 {
 409         int error;
 410
 411         acpi_bus_get_status(adev);
 412         if (adev->status.present || adev->status.functional) {
 413                 /*
 414                  * This function is only called for device objects for which
 415                  * matching scan handlers exist.  The only situation in which
 416                  * the scan handler is not attached to this device object yet
 417                  * is when the device has just appeared (either it wasn't
 418                  * present at all before or it was removed and then added
 419                  * again).
 420                  */
 421                 if (adev->handler) {
 422                         dev_warn(&adev->dev, "Already enumerated\n");
 423                         return -EALREADY;
 424                 }
 425                 error = acpi_bus_scan(adev->handle);
 426                 if (error) {
 427                         dev_warn(&adev->dev, "Namespace scan failure\n");
 428                         return error;
 429                 }
 430                 if (!adev->handler) {
 431                         dev_warn(&adev->dev, "Enumeration failure\n");
 432                         error = -ENODEV;
 433                 }
 434         } else {
 435                 error = acpi_scan_device_not_present(adev);
 436         }
 437         return error;
 438 }
 439
 440 static int acpi_scan_bus_check(struct acpi_device *adev)
 441 {
 442         struct acpi_scan_handler *handler = adev->handler;
 443         struct acpi_device *child;
 444         int error;
 445
 446         acpi_bus_get_status(adev);
 447         if (!(adev->status.present || adev->status.functional)) {
 448                 acpi_scan_device_not_present(adev);
 449                 return 0;
 450         }
 451         if (handler && handler->hotplug.scan_dependent)
 452                 return handler->hotplug.scan_dependent(adev);
 453
 454         error = acpi_bus_scan(adev->handle);
 455         if (error) {
 456                 dev_warn(&adev->dev, "Namespace scan failure\n");
 457                 return error;
 458         }
 459         list_for_each_entry(child, &adev->children, node) {
 460                 error = acpi_scan_bus_check(child);
 461                 if (error)
 462                         return error;
 463         }
 464         return 0;
 465 }
 466
 467 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
 468 {
 469         switch (type) {
 470         case ACPI_NOTIFY_BUS_CHECK:
 471                 return acpi_scan_bus_check(adev);
 472         case ACPI_NOTIFY_DEVICE_CHECK:
 473                 return acpi_scan_device_check(adev);
 474         case ACPI_NOTIFY_EJECT_REQUEST:
 475         case ACPI_OST_EC_OSPM_EJECT:
 476                 if (adev->handler && !adev->handler->hotplug.enabled) {
 477                         dev_info(&adev->dev, "Eject disabled\n");
 478                         return -EPERM;
 479                 }
 480                 acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
 481                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 482                 return acpi_scan_hot_remove(adev);
 483         }
 484         return -EINVAL;
 485 }
 486
 487 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
 488 {
 489         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 490         int error = -ENODEV;
 491
 492         lock_device_hotplug();
 493         mutex_lock(&acpi_scan_lock);
 494
 495         /*
 496          * The device object's ACPI handle cannot become invalid as long as we
 497          * are holding acpi_scan_lock, but it might have become invalid before
 498          * that lock was acquired.
 499          */
 500         if (adev->handle == INVALID_ACPI_HANDLE)
 501                 goto err_out;
 502
 503         if (adev->flags.is_dock_station) {
 504                 error = dock_notify(adev, src);
 505         } else if (adev->flags.hotplug_notify) {
 506                 error = acpi_generic_hotplug_event(adev, src);
 507                 if (error == -EPERM) {
 508                         ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 509                         goto err_out;
 510                 }
 511         } else {
 512                 int (*notify)(struct acpi_device *, u32);
 513
 514                 acpi_lock_hp_context();
 515                 notify = adev->hp ? adev->hp->notify : NULL;
 516                 acpi_unlock_hp_context();
 517                 /*
 518                  * There may be additional notify handlers for device objects
 519                  * without the .event() callback, so ignore them here.
 520                  */
 521                 if (notify)
 522                         error = notify(adev, src);
 523                 else
 524                         goto out;
 525         }
 526         if (!error)
 527                 ost_code = ACPI_OST_SC_SUCCESS;
 528
 529  err_out:
 530         acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
 531
 532  out:
 533         acpi_bus_put_acpi_device(adev);
 534         mutex_unlock(&acpi_scan_lock);
 535         unlock_device_hotplug();
 536 }
 537
 538 static ssize_t real_power_state_show(struct device *dev,
 539                                      struct device_attribute *attr, char *buf)
 540 {
 541         struct acpi_device *adev = to_acpi_device(dev);
 542         int state;
 543         int ret;
 544
 545         ret = acpi_device_get_power(adev, &state);
 546         if (ret)
 547                 return ret;
 548
 549         return sprintf(buf, "%s\n", acpi_power_state_string(state));
 550 }
 551
 552 static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL);
 553
 554 static ssize_t power_state_show(struct device *dev,
 555                                 struct device_attribute *attr, char *buf)
 556 {
 557         struct acpi_device *adev = to_acpi_device(dev);
 558
 559         return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
 560 }
 561
 562 static DEVICE_ATTR(power_state, 0444, power_state_show, NULL);
 563
 564 static ssize_t
 565 acpi_eject_store(struct device *d, struct device_attribute *attr,
 566                 const char *buf, size_t count)
 567 {
 568         struct acpi_device *acpi_device = to_acpi_device(d);
 569         acpi_object_type not_used;
 570         acpi_status status;
 571
 572         if (!count || buf[0] != '1')
 573                 return -EINVAL;
 574
 575         if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
 576             && !acpi_device->driver)
 577                 return -ENODEV;
 578
 579         status = acpi_get_type(acpi_device->handle, &not_used);
 580         if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
 581                 return -ENODEV;
 582
 583         get_device(&acpi_device->dev);
 584         status = acpi_hotplug_schedule(acpi_device, ACPI_OST_EC_OSPM_EJECT);
 585         if (ACPI_SUCCESS(status))
 586                 return count;
 587
 588         put_device(&acpi_device->dev);
 589         acpi_evaluate_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT,
 590                           ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
 591         return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
 592 }
 593
 594 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 595
 596 static ssize_t
 597 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 598         struct acpi_device *acpi_dev = to_acpi_device(dev);
 599
 600         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
 601 }
 602 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 603
 604 static ssize_t acpi_device_uid_show(struct device *dev,
 605                                     struct device_attribute *attr, char *buf)
 606 {
 607         struct acpi_device *acpi_dev = to_acpi_device(dev);
 608
 609         return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
 610 }
 611 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
 612
 613 static ssize_t acpi_device_adr_show(struct device *dev,
 614                                     struct device_attribute *attr, char *buf)
 615 {
 616         struct acpi_device *acpi_dev = to_acpi_device(dev);
 617
 618         return sprintf(buf, "0x%08x\n",
 619                        (unsigned int)(acpi_dev->pnp.bus_address));
 620 }
 621 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
 622
 623 static ssize_t
 624 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 625         struct acpi_device *acpi_dev = to_acpi_device(dev);
 626         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 627         int result;
 628
 629         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 630         if (result)
 631                 goto end;
 632
 633         result = sprintf(buf, "%s\n", (char*)path.pointer);
 634         kfree(path.pointer);
 635 end:
 636         return result;
 637 }
 638 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 639
 640 /* sysfs file that shows description text from the ACPI _STR method */
 641 static ssize_t description_show(struct device *dev,
 642                                 struct device_attribute *attr,
 643                                 char *buf) {
 644         struct acpi_device *acpi_dev = to_acpi_device(dev);
 645         int result;
 646
 647         if (acpi_dev->pnp.str_obj == NULL)
 648                 return 0;
 649
 650         /*
 651          * The _STR object contains a Unicode identifier for a device.
 652          * We need to convert to utf-8 so it can be displayed.
 653          */
 654         result = utf16s_to_utf8s(
 655                 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
 656                 acpi_dev->pnp.str_obj->buffer.length,
 657                 UTF16_LITTLE_ENDIAN, buf,
 658                 PAGE_SIZE);
 659
 660         buf[result++] = '\n';
 661
 662         return result;
 663 }
 664 static DEVICE_ATTR(description, 0444, description_show, NULL);
 665
 666 static ssize_t
 667 acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
 668                      char *buf) {
 669         struct acpi_device *acpi_dev = to_acpi_device(dev);
 670         acpi_status status;
 671         unsigned long long sun;
 672
 673         status = acpi_evaluate_integer(acpi_dev->handle, "_SUN", NULL, &sun);
 674         if (ACPI_FAILURE(status))
 675                 return -ENODEV;
 676
 677         return sprintf(buf, "%llu\n", sun);
 678 }
 679 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
 680
 681 static ssize_t status_show(struct device *dev, struct device_attribute *attr,
 682                                 char *buf) {
 683         struct acpi_device *acpi_dev = to_acpi_device(dev);
 684         acpi_status status;
 685         unsigned long long sta;
 686
 687         status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta);
 688         if (ACPI_FAILURE(status))
 689                 return -ENODEV;
 690
 691         return sprintf(buf, "%llu\n", sta);
 692 }
 693 static DEVICE_ATTR_RO(status);
 694
 695 static int acpi_device_setup_files(struct acpi_device *dev)
 696 {
 697         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 698         acpi_status status;
 699         int result = 0;
 700
 701         /*
 702          * Devices gotten from FADT don't have a "path" attribute
 703          */
 704         if (dev->handle) {
 705                 result = device_create_file(&dev->dev, &dev_attr_path);
 706                 if (result)
 707                         goto end;
 708         }
 709
 710         if (!list_empty(&dev->pnp.ids)) {
 711                 result = device_create_file(&dev->dev, &dev_attr_hid);
 712                 if (result)
 713                         goto end;
 714
 715                 result = device_create_file(&dev->dev, &dev_attr_modalias);
 716                 if (result)
 717                         goto end;
 718         }
 719
 720         /*
 721          * If device has _STR, 'description' file is created
 722          */
 723         if (acpi_has_method(dev->handle, "_STR")) {
 724                 status = acpi_evaluate_object(dev->handle, "_STR",
 725                                         NULL, &buffer);
 726                 if (ACPI_FAILURE(status))
 727                         buffer.pointer = NULL;
 728                 dev->pnp.str_obj = buffer.pointer;
 729                 result = device_create_file(&dev->dev, &dev_attr_description);
 730                 if (result)
 731                         goto end;
 732         }
 733
 734         if (dev->pnp.type.bus_address)
 735                 result = device_create_file(&dev->dev, &dev_attr_adr);
 736         if (dev->pnp.unique_id)
 737                 result = device_create_file(&dev->dev, &dev_attr_uid);
 738
 739         if (acpi_has_method(dev->handle, "_SUN")) {
 740                 result = device_create_file(&dev->dev, &dev_attr_sun);
 741                 if (result)
 742                         goto end;
 743         }
 744
 745         if (acpi_has_method(dev->handle, "_STA")) {
 746                 result = device_create_file(&dev->dev, &dev_attr_status);
 747                 if (result)
 748                         goto end;
 749         }
 750
 751         /*
 752          * If device has _EJ0, 'eject' file is created that is used to trigger
 753          * hot-removal function from userland.
 754          */
 755         if (acpi_has_method(dev->handle, "_EJ0")) {
 756                 result = device_create_file(&dev->dev, &dev_attr_eject);
 757                 if (result)
 758                         return result;
 759         }
 760
 761         if (dev->flags.power_manageable) {
 762                 result = device_create_file(&dev->dev, &dev_attr_power_state);
 763                 if (result)
 764                         return result;
 765
 766                 if (dev->power.flags.power_resources)
 767                         result = device_create_file(&dev->dev,
 768                                                     &dev_attr_real_power_state);
 769         }
 770
 771 end:
 772         return result;
 773 }
 774
 775 static void acpi_device_remove_files(struct acpi_device *dev)
 776 {
 777         if (dev->flags.power_manageable) {
 778                 device_remove_file(&dev->dev, &dev_attr_power_state);
 779                 if (dev->power.flags.power_resources)
 780                         device_remove_file(&dev->dev,
 781                                            &dev_attr_real_power_state);
 782         }
 783
 784         /*
 785          * If device has _STR, remove 'description' file
 786          */
 787         if (acpi_has_method(dev->handle, "_STR")) {
 788                 kfree(dev->pnp.str_obj);
 789                 device_remove_file(&dev->dev, &dev_attr_description);
 790         }
 791         /*
 792          * If device has _EJ0, remove 'eject' file.
 793          */
 794         if (acpi_has_method(dev->handle, "_EJ0"))
 795                 device_remove_file(&dev->dev, &dev_attr_eject);
 796
 797         if (acpi_has_method(dev->handle, "_SUN"))
 798                 device_remove_file(&dev->dev, &dev_attr_sun);
 799
 800         if (dev->pnp.unique_id)
 801                 device_remove_file(&dev->dev, &dev_attr_uid);
 802         if (dev->pnp.type.bus_address)
 803                 device_remove_file(&dev->dev, &dev_attr_adr);
 804         device_remove_file(&dev->dev, &dev_attr_modalias);
 805         device_remove_file(&dev->dev, &dev_attr_hid);
 806         if (acpi_has_method(dev->handle, "_STA"))
 807                 device_remove_file(&dev->dev, &dev_attr_status);
 808         if (dev->handle)
 809                 device_remove_file(&dev->dev, &dev_attr_path);
 810 }
 811 /* --------------------------------------------------------------------------
 812                         ACPI Bus operations
 813    -------------------------------------------------------------------------- */
 814
 815 static const struct acpi_device_id *__acpi_match_device(
 816         struct acpi_device *device, const struct acpi_device_id *ids)
 817 {
 818         const struct acpi_device_id *id;
 819         struct acpi_hardware_id *hwid;
 820
 821         /*
 822          * If the device is not present, it is unnecessary to load device
 823          * driver for it.
 824          */
 825         if (!device->status.present)
 826                 return NULL;
 827
 828         for (id = ids; id->id[0]; id++)
 829                 list_for_each_entry(hwid, &device->pnp.ids, list)
 830                         if (!strcmp((char *) id->id, hwid->id))
 831                                 return id;
 832
 833         return NULL;
 834 }
 835
 836 /**
 837  * acpi_match_device - Match a struct device against a given list of ACPI IDs
 838  * @ids: Array of struct acpi_device_id object to match against.
 839  * @dev: The device structure to match.
 840  *
 841  * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
 842  * object for that handle and use that object to match against a given list of
 843  * device IDs.
 844  *
 845  * Return a pointer to the first matching ID on success or %NULL on failure.
 846  */
 847 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
 848                                                const struct device *dev)
 849 {
 850         struct acpi_device *adev;
 851         acpi_handle handle = ACPI_HANDLE(dev);
 852
 853         if (!ids || !handle || acpi_bus_get_device(handle, &adev))
 854                 return NULL;
 855
 856         return __acpi_match_device(adev, ids);
 857 }
 858 EXPORT_SYMBOL_GPL(acpi_match_device);
 859
 860 int acpi_match_device_ids(struct acpi_device *device,
 861                           const struct acpi_device_id *ids)
 862 {
 863         return __acpi_match_device(device, ids) ? 0 : -ENOENT;
 864 }
 865 EXPORT_SYMBOL(acpi_match_device_ids);
 866
 867 static void acpi_free_power_resources_lists(struct acpi_device *device)
 868 {
 869         int i;
 870
 871         if (device->wakeup.flags.valid)
 872                 acpi_power_resources_list_free(&device->wakeup.resources);
 873
 874         if (!device->flags.power_manageable)
 875                 return;
 876
 877         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 878                 struct acpi_device_power_state *ps = &device->power.states[i];
 879                 acpi_power_resources_list_free(&ps->resources);
 880         }
 881 }
 882
 883 static void acpi_device_release(struct device *dev)
 884 {
 885         struct acpi_device *acpi_dev = to_acpi_device(dev);
 886
 887         acpi_free_pnp_ids(&acpi_dev->pnp);
 888         acpi_free_power_resources_lists(acpi_dev);
 889         kfree(acpi_dev);
 890 }
 891
 892 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 893 {
 894         struct acpi_device *acpi_dev = to_acpi_device(dev);
 895         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 896
 897         return acpi_dev->flags.match_driver
 898                 && !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 899 }
 900
 901 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 902 {
 903         struct acpi_device *acpi_dev = to_acpi_device(dev);
 904         int len;
 905
 906         if (list_empty(&acpi_dev->pnp.ids))
 907                 return 0;
 908
 909         if (add_uevent_var(env, "MODALIAS="))
 910                 return -ENOMEM;
 911         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 912                               sizeof(env->buf) - env->buflen);
 913         if (len <= 0)
 914                 return len;
 915         env->buflen += len;
 916         return 0;
 917 }
 918
 919 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 920 {
 921         struct acpi_device *device = data;
 922
 923         device->driver->ops.notify(device, event);
 924 }
 925
 926 static void acpi_device_notify_fixed(void *data)
 927 {
 928         struct acpi_device *device = data;
 929
 930         /* Fixed hardware devices have no handles */
 931         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 932 }
 933
 934 static acpi_status acpi_device_fixed_event(void *data)
 935 {
 936         acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_device_notify_fixed, data);
 937         return AE_OK;
 938 }
 939
 940 static int acpi_device_install_notify_handler(struct acpi_device *device)
 941 {
 942         acpi_status status;
 943
 944         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 945                 status =
 946                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 947                                                      acpi_device_fixed_event,
 948                                                      device);
 949         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 950                 status =
 951                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 952                                                      acpi_device_fixed_event,
 953                                                      device);
 954         else
 955                 status = acpi_install_notify_handler(device->handle,
 956                                                      ACPI_DEVICE_NOTIFY,
 957                                                      acpi_device_notify,
 958                                                      device);
 959
 960         if (ACPI_FAILURE(status))
 961                 return -EINVAL;
 962         return 0;
 963 }
 964
 965 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 966 {
 967         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 968                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 969                                                 acpi_device_fixed_event);
 970         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 971                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 972                                                 acpi_device_fixed_event);
 973         else
 974                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 975                                            acpi_device_notify);
 976 }
 977
 978 static int acpi_device_probe(struct device *dev)
 979 {
 980         struct acpi_device *acpi_dev = to_acpi_device(dev);
 981         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 982         int ret;
 983
 984         if (acpi_dev->handler && !acpi_is_pnp_device(acpi_dev))
 985                 return -EINVAL;
 986
 987         if (!acpi_drv->ops.add)
 988                 return -ENOSYS;
 989
 990         ret = acpi_drv->ops.add(acpi_dev);
 991         if (ret)
 992                 return ret;
 993
 994         acpi_dev->driver = acpi_drv;
 995         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 996                           "Driver [%s] successfully bound to device [%s]\n",
 997                           acpi_drv->name, acpi_dev->pnp.bus_id));
 998
 999         if (acpi_drv->ops.notify) {
1000                 ret = acpi_device_install_notify_handler(acpi_dev);
1001                 if (ret) {
1002                         if (acpi_drv->ops.remove)
1003                                 acpi_drv->ops.remove(acpi_dev);
1004
1005                         acpi_dev->driver = NULL;
1006                         acpi_dev->driver_data = NULL;
1007                         return ret;
1008                 }
1009         }
1010
1011         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
1012                           acpi_drv->name, acpi_dev->pnp.bus_id));
1013         get_device(dev);
1014         return 0;
1015 }
1016
1017 static int acpi_device_remove(struct device * dev)
1018 {
1019         struct acpi_device *acpi_dev = to_acpi_device(dev);
1020         struct acpi_driver *acpi_drv = acpi_dev->driver;
1021
1022         if (acpi_drv) {
1023                 if (acpi_drv->ops.notify)
1024                         acpi_device_remove_notify_handler(acpi_dev);
1025                 if (acpi_drv->ops.remove)
1026                         acpi_drv->ops.remove(acpi_dev);
1027         }
1028         acpi_dev->driver = NULL;
1029         acpi_dev->driver_data = NULL;
1030
1031         put_device(dev);
1032         return 0;
1033 }
1034
1035 struct bus_type acpi_bus_type = {
1036         .name           = "acpi",
1037         .match          = acpi_bus_match,
1038         .probe          = acpi_device_probe,
1039         .remove         = acpi_device_remove,
1040         .uevent         = acpi_device_uevent,
1041 };
1042
1043 static void acpi_device_del(struct acpi_device *device)
1044 {
1045         mutex_lock(&acpi_device_lock);
1046         if (device->parent)
1047                 list_del(&device->node);
1048
1049         list_del(&device->wakeup_list);
1050         mutex_unlock(&acpi_device_lock);
1051
1052         acpi_power_add_remove_device(device, false);
1053         acpi_device_remove_files(device);
1054         if (device->remove)
1055                 device->remove(device);
1056
1057         device_del(&device->dev);
1058 }
1059
1060 static LIST_HEAD(acpi_device_del_list);
1061 static DEFINE_MUTEX(acpi_device_del_lock);
1062
1063 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
1064 {
1065         for (;;) {
1066                 struct acpi_device *adev;
1067
1068                 mutex_lock(&acpi_device_del_lock);
1069
1070                 if (list_empty(&acpi_device_del_list)) {
1071                         mutex_unlock(&acpi_device_del_lock);
1072                         break;
1073                 }
1074                 adev = list_first_entry(&acpi_device_del_list,
1075                                         struct acpi_device, del_list);
1076                 list_del(&adev->del_list);
1077
1078                 mutex_unlock(&acpi_device_del_lock);
1079
1080                 acpi_device_del(adev);
1081                 /*
1082                  * Drop references to all power resources that might have been
1083                  * used by the device.
1084                  */
1085                 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
1086                 put_device(&adev->dev);
1087         }
1088 }
1089
1090 /**
1091  * acpi_scan_drop_device - Drop an ACPI device object.
1092  * @handle: Handle of an ACPI namespace node, not used.
1093  * @context: Address of the ACPI device object to drop.
1094  *
1095  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
1096  * namespace node the device object pointed to by @context is attached to.
1097  *
1098  * The unregistration is carried out asynchronously to avoid running
1099  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
1100  * ensure the correct ordering (the device objects must be unregistered in the
1101  * same order in which the corresponding namespace nodes are deleted).
1102  */
1103 static void acpi_scan_drop_device(acpi_handle handle, void *context)
1104 {
1105         static DECLARE_WORK(work, acpi_device_del_work_fn);
1106         struct acpi_device *adev = context;
1107
1108         mutex_lock(&acpi_device_del_lock);
1109
1110         /*
1111          * Use the ACPI hotplug workqueue which is ordered, so this work item
1112          * won't run after any hotplug work items submitted subsequently.  That
1113          * prevents attempts to register device objects identical to those being
1114          * deleted from happening concurrently (such attempts result from
1115          * hotplug events handled via the ACPI hotplug workqueue).  It also will
1116          * run after all of the work items submitted previosuly, which helps
1117          * those work items to ensure that they are not accessing stale device
1118          * objects.
1119          */
1120         if (list_empty(&acpi_device_del_list))
1121                 acpi_queue_hotplug_work(&work);
1122
1123         list_add_tail(&adev->del_list, &acpi_device_del_list);
1124         /* Make acpi_ns_validate_handle() return NULL for this handle. */
1125         adev->handle = INVALID_ACPI_HANDLE;
1126
1127         mutex_unlock(&acpi_device_del_lock);
1128 }
1129
1130 static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
1131                                 void (*callback)(void *))
1132 {
1133         acpi_status status;
1134
1135         if (!device)
1136                 return -EINVAL;
1137
1138         status = acpi_get_data_full(handle, acpi_scan_drop_device,
1139                                     (void **)device, callback);
1140         if (ACPI_FAILURE(status) || !*device) {
1141                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
1142                                   handle));
1143                 return -ENODEV;
1144         }
1145         return 0;
1146 }
1147
1148 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
1149 {
1150         return acpi_get_device_data(handle, device, NULL);
1151 }
1152 EXPORT_SYMBOL(acpi_bus_get_device);
1153
1154 static void get_acpi_device(void *dev)
1155 {
1156         if (dev)
1157                 get_device(&((struct acpi_device *)dev)->dev);
1158 }
1159
1160 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
1161 {
1162         struct acpi_device *adev = NULL;
1163
1164         acpi_get_device_data(handle, &adev, get_acpi_device);
1165         return adev;
1166 }
1167
1168 void acpi_bus_put_acpi_device(struct acpi_device *adev)
1169 {
1170         put_device(&adev->dev);
1171 }
1172
1173 int acpi_device_add(struct acpi_device *device,
1174                     void (*release)(struct device *))
1175 {
1176         int result;
1177         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
1178         int found = 0;
1179
1180         if (device->handle) {
1181                 acpi_status status;
1182
1183                 status = acpi_attach_data(device->handle, acpi_scan_drop_device,
1184                                           device);
1185                 if (ACPI_FAILURE(status)) {
1186                         acpi_handle_err(device->handle,
1187                                         "Unable to attach device data\n");
1188                         return -ENODEV;
1189                 }
1190         }
1191
1192         /*
1193          * Linkage
1194          * -------
1195          * Link this device to its parent and siblings.
1196          */
1197         INIT_LIST_HEAD(&device->children);
1198         INIT_LIST_HEAD(&device->node);
1199         INIT_LIST_HEAD(&device->wakeup_list);
1200         INIT_LIST_HEAD(&device->physical_node_list);
1201         INIT_LIST_HEAD(&device->del_list);
1202         mutex_init(&device->physical_node_lock);
1203
1204         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
1205         if (!new_bus_id) {
1206                 pr_err(PREFIX "Memory allocation error\n");
1207                 result = -ENOMEM;
1208                 goto err_detach;
1209         }
1210
1211         mutex_lock(&acpi_device_lock);
1212         /*
1213          * Find suitable bus_id and instance number in acpi_bus_id_list
1214          * If failed, create one and link it into acpi_bus_id_list
1215          */
1216         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
1217                 if (!strcmp(acpi_device_bus_id->bus_id,
1218                             acpi_device_hid(device))) {
1219                         acpi_device_bus_id->instance_no++;
1220                         found = 1;
1221                         kfree(new_bus_id);
1222                         break;
1223                 }
1224         }
1225         if (!found) {
1226                 acpi_device_bus_id = new_bus_id;
1227                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
1228                 acpi_device_bus_id->instance_no = 0;
1229                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
1230         }
1231         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
1232
1233         if (device->parent)
1234                 list_add_tail(&device->node, &device->parent->children);
1235
1236         if (device->wakeup.flags.valid)
1237                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
1238         mutex_unlock(&acpi_device_lock);
1239
1240         if (device->parent)
1241                 device->dev.parent = &device->parent->dev;
1242         device->dev.bus = &acpi_bus_type;
1243         device->dev.release = release;
1244         result = device_add(&device->dev);
1245         if (result) {
1246                 dev_err(&device->dev, "Error registering device\n");
1247                 goto err;
1248         }
1249
1250         result = acpi_device_setup_files(device);
1251         if (result)
1252                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
1253                        dev_name(&device->dev));
1254
1255         return 0;
1256
1257  err:
1258         mutex_lock(&acpi_device_lock);
1259         if (device->parent)
1260                 list_del(&device->node);
1261         list_del(&device->wakeup_list);
1262         mutex_unlock(&acpi_device_lock);
1263
1264  err_detach:
1265         acpi_detach_data(device->handle, acpi_scan_drop_device);
1266         return result;
1267 }
1268
1269 /* --------------------------------------------------------------------------
1270                                  Driver Management
1271    -------------------------------------------------------------------------- */
1272 /**
1273  * acpi_bus_register_driver - register a driver with the ACPI bus
1274  * @driver: driver being registered
1275  *
1276  * Registers a driver with the ACPI bus.  Searches the namespace for all
1277  * devices that match the driver's criteria and binds.  Returns zero for
1278  * success or a negative error status for failure.
1279  */
1280 int acpi_bus_register_driver(struct acpi_driver *driver)
1281 {
1282         int ret;
1283
1284         if (acpi_disabled)
1285                 return -ENODEV;
1286         driver->drv.name = driver->name;
1287         driver->drv.bus = &acpi_bus_type;
1288         driver->drv.owner = driver->owner;
1289
1290         ret = driver_register(&driver->drv);
1291         return ret;
1292 }
1293
1294 EXPORT_SYMBOL(acpi_bus_register_driver);
1295
1296 /**
1297  * acpi_bus_unregister_driver - unregisters a driver with the ACPI bus
1298  * @driver: driver to unregister
1299  *
1300  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
1301  * devices that match the driver's criteria and unbinds.
1302  */
1303 void acpi_bus_unregister_driver(struct acpi_driver *driver)
1304 {
1305         driver_unregister(&driver->drv);
1306 }
1307
1308 EXPORT_SYMBOL(acpi_bus_unregister_driver);
1309
1310 /* --------------------------------------------------------------------------
1311                                  Device Enumeration
1312    -------------------------------------------------------------------------- */
1313 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
1314 {
1315         struct acpi_device *device = NULL;
1316         acpi_status status;
1317
1318         /*
1319          * Fixed hardware devices do not appear in the namespace and do not
1320          * have handles, but we fabricate acpi_devices for them, so we have
1321          * to deal with them specially.
1322          */
1323         if (!handle)
1324                 return acpi_root;
1325
1326         do {
1327                 status = acpi_get_parent(handle, &handle);
1328                 if (ACPI_FAILURE(status))
1329                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
1330         } while (acpi_bus_get_device(handle, &device));
1331         return device;
1332 }
1333
1334 acpi_status
1335 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
1336 {
1337         acpi_status status;
1338         acpi_handle tmp;
1339         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
1340         union acpi_object *obj;
1341
1342         status = acpi_get_handle(handle, "_EJD", &tmp);
1343         if (ACPI_FAILURE(status))
1344                 return status;
1345
1346         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
1347         if (ACPI_SUCCESS(status)) {
1348                 obj = buffer.pointer;
1349                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
1350                                          ejd);
1351                 kfree(buffer.pointer);
1352         }
1353         return status;
1354 }
1355 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
1356
1357 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
1358                                         struct acpi_device_wakeup *wakeup)
1359 {
1360         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1361         union acpi_object *package = NULL;
1362         union acpi_object *element = NULL;
1363         acpi_status status;
1364         int err = -ENODATA;
1365
1366         if (!wakeup)
1367                 return -EINVAL;
1368
1369         INIT_LIST_HEAD(&wakeup->resources);
1370
1371         /* _PRW */
1372         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
1373         if (ACPI_FAILURE(status)) {
1374                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
1375                 return err;
1376         }
1377
1378         package = (union acpi_object *)buffer.pointer;
1379
1380         if (!package || package->package.count < 2)
1381                 goto out;
1382
1383         element = &(package->package.elements[0]);
1384         if (!element)
1385                 goto out;
1386
1387         if (element->type == ACPI_TYPE_PACKAGE) {
1388                 if ((element->package.count < 2) ||
1389                     (element->package.elements[0].type !=
1390                      ACPI_TYPE_LOCAL_REFERENCE)
1391                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
1392                         goto out;
1393
1394                 wakeup->gpe_device =
1395                     element->package.elements[0].reference.handle;
1396                 wakeup->gpe_number =
1397                     (u32) element->package.elements[1].integer.value;
1398         } else if (element->type == ACPI_TYPE_INTEGER) {
1399                 wakeup->gpe_device = NULL;
1400                 wakeup->gpe_number = element->integer.value;
1401         } else {
1402                 goto out;
1403         }
1404
1405         element = &(package->package.elements[1]);
1406         if (element->type != ACPI_TYPE_INTEGER)
1407                 goto out;
1408
1409         wakeup->sleep_state = element->integer.value;
1410
1411         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
1412         if (err)
1413                 goto out;
1414
1415         if (!list_empty(&wakeup->resources)) {
1416                 int sleep_state;
1417
1418                 err = acpi_power_wakeup_list_init(&wakeup->resources,
1419                                                   &sleep_state);
1420                 if (err) {
1421                         acpi_handle_warn(handle, "Retrieving current states "
1422                                          "of wakeup power resources failed\n");
1423                         acpi_power_resources_list_free(&wakeup->resources);
1424                         goto out;
1425                 }
1426                 if (sleep_state < wakeup->sleep_state) {
1427                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
1428                                          "(S%d) by S%d from power resources\n",
1429                                          (int)wakeup->sleep_state, sleep_state);
1430                         wakeup->sleep_state = sleep_state;
1431                 }
1432         }
1433
1434  out:
1435         kfree(buffer.pointer);
1436         return err;
1437 }
1438
1439 static void acpi_wakeup_gpe_init(struct acpi_device *device)
1440 {
1441         struct acpi_device_id button_device_ids[] = {
1442                 {"PNP0C0C", 0},
1443                 {"PNP0C0D", 0},
1444                 {"PNP0C0E", 0},
1445                 {"", 0},
1446         };
1447         struct acpi_device_wakeup *wakeup = &device->wakeup;
1448         acpi_status status;
1449         acpi_event_status event_status;
1450
1451         wakeup->flags.notifier_present = 0;
1452
1453         /* Power button, Lid switch always enable wakeup */
1454         if (!acpi_match_device_ids(device, button_device_ids)) {
1455                 wakeup->flags.run_wake = 1;
1456                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
1457                         /* Do not use Lid/sleep button for S5 wakeup */
1458                         if (wakeup->sleep_state == ACPI_STATE_S5)
1459                                 wakeup->sleep_state = ACPI_STATE_S4;
1460                 }
1461                 acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
1462                 device_set_wakeup_capable(&device->dev, true);
1463                 return;
1464         }
1465
1466         acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
1467                                 wakeup->gpe_number);
1468         status = acpi_get_gpe_status(wakeup->gpe_device, wakeup->gpe_number,
1469                                      &event_status);
1470         if (ACPI_FAILURE(status))
1471                 return;
1472
1473         wakeup->flags.run_wake = !!(event_status & ACPI_EVENT_FLAG_HANDLE);
1474 }
1475
1476 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1477 {
1478         int err;
1479
1480         /* Presence of _PRW indicates wake capable */
1481         if (!acpi_has_method(device->handle, "_PRW"))
1482                 return;
1483
1484         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
1485                                                            &device->wakeup);
1486         if (err) {
1487                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
1488                 return;
1489         }
1490
1491         device->wakeup.flags.valid = 1;
1492         device->wakeup.prepare_count = 0;
1493         acpi_wakeup_gpe_init(device);
1494         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
1495          * system for the ACPI device with the _PRW object.
1496          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
1497          * So it is necessary to call _DSW object first. Only when it is not
1498          * present will the _PSW object used.
1499          */
1500         err = acpi_device_sleep_wake(device, 0, 0, 0);
1501         if (err)
1502                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1503                                 "error in _DSW or _PSW evaluation\n"));
1504 }
1505
1506 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1507 {
1508         struct acpi_device_power_state *ps = &device->power.states[state];
1509         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1510         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1511         acpi_status status;
1512
1513         INIT_LIST_HEAD(&ps->resources);
1514
1515         /* Evaluate "_PRx" to get referenced power resources */
1516         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1517         if (ACPI_SUCCESS(status)) {
1518                 union acpi_object *package = buffer.pointer;
1519
1520                 if (buffer.length && package
1521                     && package->type == ACPI_TYPE_PACKAGE
1522                     && package->package.count) {
1523                         int err = acpi_extract_power_resources(package, 0,
1524                                                                &ps->resources);
1525                         if (!err)
1526                                 device->power.flags.power_resources = 1;
1527                 }
1528                 ACPI_FREE(buffer.pointer);
1529         }
1530
1531         /* Evaluate "_PSx" to see if we can do explicit sets */
1532         pathname[2] = 'S';
1533         if (acpi_has_method(device->handle, pathname))
1534                 ps->flags.explicit_set = 1;
1535
1536         /*
1537          * State is valid if there are means to put the device into it.
1538          * D3hot is only valid if _PR3 present.
1539          */
1540         if (!list_empty(&ps->resources)
1541             || (ps->flags.explicit_set && state < ACPI_STATE_D3_HOT)) {
1542                 ps->flags.valid = 1;
1543                 ps->flags.os_accessible = 1;
1544         }
1545
1546         ps->power = -1;         /* Unknown - driver assigned */
1547         ps->latency = -1;       /* Unknown - driver assigned */
1548 }
1549
1550 static void acpi_bus_get_power_flags(struct acpi_device *device)
1551 {
1552         u32 i;
1553
1554         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1555         if (!acpi_has_method(device->handle, "_PS0") &&
1556             !acpi_has_method(device->handle, "_PR0"))
1557                 return;
1558
1559         device->flags.power_manageable = 1;
1560
1561         /*
1562          * Power Management Flags
1563          */
1564         if (acpi_has_method(device->handle, "_PSC"))
1565                 device->power.flags.explicit_get = 1;
1566
1567         if (acpi_has_method(device->handle, "_IRC"))
1568                 device->power.flags.inrush_current = 1;
1569
1570         if (acpi_has_method(device->handle, "_DSW"))
1571                 device->power.flags.dsw_present = 1;
1572
1573         /*
1574          * Enumerate supported power management states
1575          */
1576         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1577                 acpi_bus_init_power_state(device, i);
1578
1579         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1580
1581         /* Set defaults for D0 and D3 states (always valid) */
1582         device->power.states[ACPI_STATE_D0].flags.valid = 1;
1583         device->power.states[ACPI_STATE_D0].power = 100;
1584         device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
1585         device->power.states[ACPI_STATE_D3_COLD].power = 0;
1586
1587         /* Set D3cold's explicit_set flag if _PS3 exists. */
1588         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
1589                 device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
1590
1591         /* Presence of _PS3 or _PRx means we can put the device into D3 cold */
1592         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set ||
1593                         device->power.flags.power_resources)
1594                 device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
1595
1596         if (acpi_bus_init_power(device)) {
1597                 acpi_free_power_resources_lists(device);
1598                 device->flags.power_manageable = 0;
1599         }
1600 }
1601
1602 static void acpi_bus_get_flags(struct acpi_device *device)
1603 {
1604         /* Presence of _STA indicates 'dynamic_status' */
1605         if (acpi_has_method(device->handle, "_STA"))
1606                 device->flags.dynamic_status = 1;
1607
1608         /* Presence of _RMV indicates 'removable' */
1609         if (acpi_has_method(device->handle, "_RMV"))
1610                 device->flags.removable = 1;
1611
1612         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1613         if (acpi_has_method(device->handle, "_EJD") ||
1614             acpi_has_method(device->handle, "_EJ0"))
1615                 device->flags.ejectable = 1;
1616 }
1617
1618 static void acpi_device_get_busid(struct acpi_device *device)
1619 {
1620         char bus_id[5] = { '?', 0 };
1621         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1622         int i = 0;
1623
1624         /*
1625          * Bus ID
1626          * ------
1627          * The device's Bus ID is simply the object name.
1628          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1629          */
1630         if (ACPI_IS_ROOT_DEVICE(device)) {
1631                 strcpy(device->pnp.bus_id, "ACPI");
1632                 return;
1633         }
1634
1635         switch (device->device_type) {
1636         case ACPI_BUS_TYPE_POWER_BUTTON:
1637                 strcpy(device->pnp.bus_id, "PWRF");
1638                 break;
1639         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1640                 strcpy(device->pnp.bus_id, "SLPF");
1641                 break;
1642         default:
1643                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1644                 /* Clean up trailing underscores (if any) */
1645                 for (i = 3; i > 1; i--) {
1646                         if (bus_id[i] == '_')
1647                                 bus_id[i] = '\0';
1648                         else
1649                                 break;
1650                 }
1651                 strcpy(device->pnp.bus_id, bus_id);
1652                 break;
1653         }
1654 }
1655
1656 /*
1657  * acpi_ata_match - see if an acpi object is an ATA device
1658  *
1659  * If an acpi object has one of the ACPI ATA methods defined,
1660  * then we can safely call it an ATA device.
1661  */
1662 bool acpi_ata_match(acpi_handle handle)
1663 {
1664         return acpi_has_method(handle, "_GTF") ||
1665                acpi_has_method(handle, "_GTM") ||
1666                acpi_has_method(handle, "_STM") ||
1667                acpi_has_method(handle, "_SDD");
1668 }
1669
1670 /*
1671  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1672  *
1673  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1674  * then we can safely call it an ejectable drive bay
1675  */
1676 bool acpi_bay_match(acpi_handle handle)
1677 {
1678         acpi_handle phandle;
1679
1680         if (!acpi_has_method(handle, "_EJ0"))
1681                 return false;
1682         if (acpi_ata_match(handle))
1683                 return true;
1684         if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1685                 return false;
1686
1687         return acpi_ata_match(phandle);
1688 }
1689
1690 bool acpi_device_is_battery(struct acpi_device *adev)
1691 {
1692         struct acpi_hardware_id *hwid;
1693
1694         list_for_each_entry(hwid, &adev->pnp.ids, list)
1695                 if (!strcmp("PNP0C0A", hwid->id))
1696                         return true;
1697
1698         return false;
1699 }
1700
1701 static bool is_ejectable_bay(struct acpi_device *adev)
1702 {
1703         acpi_handle handle = adev->handle;
1704
1705         if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1706                 return true;
1707
1708         return acpi_bay_match(handle);
1709 }
1710
1711 /*
1712  * acpi_dock_match - see if an acpi object has a _DCK method
1713  */
1714 bool acpi_dock_match(acpi_handle handle)
1715 {
1716         return acpi_has_method(handle, "_DCK");
1717 }
1718
1719 const char *acpi_device_hid(struct acpi_device *device)
1720 {
1721         struct acpi_hardware_id *hid;
1722
1723         if (list_empty(&device->pnp.ids))
1724                 return dummy_hid;
1725
1726         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1727         return hid->id;
1728 }
1729 EXPORT_SYMBOL(acpi_device_hid);
1730
1731 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1732 {
1733         struct acpi_hardware_id *id;
1734
1735         id = kmalloc(sizeof(*id), GFP_KERNEL);
1736         if (!id)
1737                 return;
1738
1739         id->id = kstrdup(dev_id, GFP_KERNEL);
1740         if (!id->id) {
1741                 kfree(id);
1742                 return;
1743         }
1744
1745         list_add_tail(&id->list, &pnp->ids);
1746         pnp->type.hardware_id = 1;
1747 }
1748
1749 /*
1750  * Old IBM workstations have a DSDT bug wherein the SMBus object
1751  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1752  * prefix.  Work around this.
1753  */
1754 static bool acpi_ibm_smbus_match(acpi_handle handle)
1755 {
1756         char node_name[ACPI_PATH_SEGMENT_LENGTH];
1757         struct acpi_buffer path = { sizeof(node_name), node_name };
1758
1759         if (!dmi_name_in_vendors("IBM"))
1760                 return false;
1761
1762         /* Look for SMBS object */
1763         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1764             strcmp("SMBS", path.pointer))
1765                 return false;
1766
1767         /* Does it have the necessary (but misnamed) methods? */
1768         if (acpi_has_method(handle, "SBI") &&
1769             acpi_has_method(handle, "SBR") &&
1770             acpi_has_method(handle, "SBW"))
1771                 return true;
1772
1773         return false;
1774 }
1775
1776 static bool acpi_object_is_system_bus(acpi_handle handle)
1777 {
1778         acpi_handle tmp;
1779
1780         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1781             tmp == handle)
1782                 return true;
1783         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1784             tmp == handle)
1785                 return true;
1786
1787         return false;
1788 }
1789
1790 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1791                                 int device_type)
1792 {
1793         acpi_status status;
1794         struct acpi_device_info *info;
1795         struct acpi_pnp_device_id_list *cid_list;
1796         int i;
1797
1798         switch (device_type) {
1799         case ACPI_BUS_TYPE_DEVICE:
1800                 if (handle == ACPI_ROOT_OBJECT) {
1801                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1802                         break;
1803                 }
1804
1805                 status = acpi_get_object_info(handle, &info);
1806                 if (ACPI_FAILURE(status)) {
1807                         pr_err(PREFIX "%s: Error reading device info\n",
1808                                         __func__);
1809                         return;
1810                 }
1811
1812                 if (info->valid & ACPI_VALID_HID) {
1813                         acpi_add_id(pnp, info->hardware_id.string);
1814                         pnp->type.platform_id = 1;
1815                 }
1816                 if (info->valid & ACPI_VALID_CID) {
1817                         cid_list = &info->compatible_id_list;
1818                         for (i = 0; i < cid_list->count; i++)
1819                                 acpi_add_id(pnp, cid_list->ids[i].string);
1820                 }
1821                 if (info->valid & ACPI_VALID_ADR) {
1822                         pnp->bus_address = info->address;
1823                         pnp->type.bus_address = 1;
1824                 }
1825                 if (info->valid & ACPI_VALID_UID)
1826                         pnp->unique_id = kstrdup(info->unique_id.string,
1827                                                         GFP_KERNEL);
1828
1829                 kfree(info);
1830
1831                 /*
1832                  * Some devices don't reliably have _HIDs & _CIDs, so add
1833                  * synthetic HIDs to make sure drivers can find them.
1834                  */
1835                 if (acpi_is_video_device(handle))
1836                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1837                 else if (acpi_bay_match(handle))
1838                         acpi_add_id(pnp, ACPI_BAY_HID);
1839                 else if (acpi_dock_match(handle))
1840                         acpi_add_id(pnp, ACPI_DOCK_HID);
1841                 else if (acpi_ibm_smbus_match(handle))
1842                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1843                 else if (list_empty(&pnp->ids) &&
1844                          acpi_object_is_system_bus(handle)) {
1845                         /* \_SB, \_TZ, LNXSYBUS */
1846                         acpi_add_id(pnp, ACPI_BUS_HID);
1847                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1848                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1849                 }
1850
1851                 break;
1852         case ACPI_BUS_TYPE_POWER:
1853                 acpi_add_id(pnp, ACPI_POWER_HID);
1854                 break;
1855         case ACPI_BUS_TYPE_PROCESSOR:
1856                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1857                 break;
1858         case ACPI_BUS_TYPE_THERMAL:
1859                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1860                 break;
1861         case ACPI_BUS_TYPE_POWER_BUTTON:
1862                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1863                 break;
1864         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1865                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1866                 break;
1867         }
1868 }
1869
1870 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1871 {
1872         struct acpi_hardware_id *id, *tmp;
1873
1874         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1875                 kfree(id->id);
1876                 kfree(id);
1877         }
1878         kfree(pnp->unique_id);
1879 }
1880
1881 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1882                              int type, unsigned long long sta)
1883 {
1884         INIT_LIST_HEAD(&device->pnp.ids);
1885         device->device_type = type;
1886         device->handle = handle;
1887         device->parent = acpi_bus_get_parent(handle);
1888         acpi_set_device_status(device, sta);
1889         acpi_device_get_busid(device);
1890         acpi_set_pnp_ids(handle, &device->pnp, type);
1891         acpi_bus_get_flags(device);
1892         device->flags.match_driver = false;
1893         device->flags.initialized = true;
1894         device->flags.visited = false;
1895         device_initialize(&device->dev);
1896         dev_set_uevent_suppress(&device->dev, true);
1897 }
1898
1899 void acpi_device_add_finalize(struct acpi_device *device)
1900 {
1901         dev_set_uevent_suppress(&device->dev, false);
1902         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1903 }
1904
1905 static int acpi_add_single_object(struct acpi_device **child,
1906                                   acpi_handle handle, int type,
1907                                   unsigned long long sta)
1908 {
1909         int result;
1910         struct acpi_device *device;
1911         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1912
1913         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1914         if (!device) {
1915                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1916                 return -ENOMEM;
1917         }
1918
1919         acpi_init_device_object(device, handle, type, sta);
1920         acpi_bus_get_power_flags(device);
1921         acpi_bus_get_wakeup_device_flags(device);
1922
1923         result = acpi_device_add(device, acpi_device_release);
1924         if (result) {
1925                 acpi_device_release(&device->dev);
1926                 return result;
1927         }
1928
1929         acpi_power_add_remove_device(device, true);
1930         acpi_device_add_finalize(device);
1931         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1932         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1933                 dev_name(&device->dev), (char *) buffer.pointer,
1934                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1935         kfree(buffer.pointer);
1936         *child = device;
1937         return 0;
1938 }
1939
1940 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1941                                     unsigned long long *sta)
1942 {
1943         acpi_status status;
1944         acpi_object_type acpi_type;
1945
1946         status = acpi_get_type(handle, &acpi_type);
1947         if (ACPI_FAILURE(status))
1948                 return -ENODEV;
1949
1950         switch (acpi_type) {
1951         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1952         case ACPI_TYPE_DEVICE:
1953                 *type = ACPI_BUS_TYPE_DEVICE;
1954                 status = acpi_bus_get_status_handle(handle, sta);
1955                 if (ACPI_FAILURE(status))
1956                         return -ENODEV;
1957                 break;
1958         case ACPI_TYPE_PROCESSOR:
1959                 *type = ACPI_BUS_TYPE_PROCESSOR;
1960                 status = acpi_bus_get_status_handle(handle, sta);
1961                 if (ACPI_FAILURE(status))
1962                         return -ENODEV;
1963                 break;
1964         case ACPI_TYPE_THERMAL:
1965                 *type = ACPI_BUS_TYPE_THERMAL;
1966                 *sta = ACPI_STA_DEFAULT;
1967                 break;
1968         case ACPI_TYPE_POWER:
1969                 *type = ACPI_BUS_TYPE_POWER;
1970                 *sta = ACPI_STA_DEFAULT;
1971                 break;
1972         default:
1973                 return -ENODEV;
1974         }
1975
1976         return 0;
1977 }
1978
1979 bool acpi_device_is_present(struct acpi_device *adev)
1980 {
1981         if (adev->status.present || adev->status.functional)
1982                 return true;
1983
1984         adev->flags.initialized = false;
1985         return false;
1986 }
1987
1988 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1989                                        char *idstr,
1990                                        const struct acpi_device_id **matchid)
1991 {
1992         const struct acpi_device_id *devid;
1993
1994         if (handler->match)
1995                 return handler->match(idstr, matchid);
1996
1997         for (devid = handler->ids; devid->id[0]; devid++)
1998                 if (!strcmp((char *)devid->id, idstr)) {
1999                         if (matchid)
2000                                 *matchid = devid;
2001
2002                         return true;
2003                 }
2004
2005         return false;
2006 }
2007
2008 static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr,
2009                                         const struct acpi_device_id **matchid)
2010 {
2011         struct acpi_scan_handler *handler;
2012
2013         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
2014                 if (acpi_scan_handler_matching(handler, idstr, matchid))
2015                         return handler;
2016
2017         return NULL;
2018 }
2019
2020 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
2021 {
2022         if (!!hotplug->enabled == !!val)
2023                 return;
2024
2025         mutex_lock(&acpi_scan_lock);
2026
2027         hotplug->enabled = val;
2028
2029         mutex_unlock(&acpi_scan_lock);
2030 }
2031
2032 static void acpi_scan_init_hotplug(struct acpi_device *adev)
2033 {
2034         struct acpi_hardware_id *hwid;
2035
2036         if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
2037                 acpi_dock_add(adev);
2038                 return;
2039         }
2040         list_for_each_entry(hwid, &adev->pnp.ids, list) {
2041                 struct acpi_scan_handler *handler;
2042
2043                 handler = acpi_scan_match_handler(hwid->id, NULL);
2044                 if (handler) {
2045                         adev->flags.hotplug_notify = true;
2046                         break;
2047                 }
2048         }
2049 }
2050
2051 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
2052                                       void *not_used, void **return_value)
2053 {
2054         struct acpi_device *device = NULL;
2055         int type;
2056         unsigned long long sta;
2057         int result;
2058
2059         acpi_bus_get_device(handle, &device);
2060         if (device)
2061                 goto out;
2062
2063         result = acpi_bus_type_and_status(handle, &type, &sta);
2064         if (result)
2065                 return AE_OK;
2066
2067         if (type == ACPI_BUS_TYPE_POWER) {
2068                 acpi_add_power_resource(handle);
2069                 return AE_OK;
2070         }
2071
2072         acpi_add_single_object(&device, handle, type, sta);
2073         if (!device)
2074                 return AE_CTRL_DEPTH;
2075
2076         acpi_scan_init_hotplug(device);
2077
2078  out:
2079         if (!*return_value)
2080                 *return_value = device;
2081
2082         return AE_OK;
2083 }
2084
2085 static int acpi_check_spi_i2c_slave(struct acpi_resource *ares, void *data)
2086 {
2087         bool *is_spi_i2c_slave_p = data;
2088
2089         if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
2090                 return 1;
2091
2092         /*
2093          * devices that are connected to UART still need to be enumerated to
2094          * platform bus
2095          */
2096         if (ares->data.common_serial_bus.type != ACPI_RESOURCE_SERIAL_TYPE_UART)
2097                 *is_spi_i2c_slave_p = true;
2098
2099          /* no need to do more checking */
2100         return -1;
2101 }
2102
2103 static void acpi_default_enumeration(struct acpi_device *device)
2104 {
2105         struct list_head resource_list;
2106         bool is_spi_i2c_slave = false;
2107
2108         if (!device->pnp.type.platform_id || device->handler)
2109                 return;
2110
2111         /*
2112          * Do not enemerate SPI/I2C slaves as they will be enuerated by their
2113          * respective parents.
2114          */
2115         INIT_LIST_HEAD(&resource_list);
2116         acpi_dev_get_resources(device, &resource_list, acpi_check_spi_i2c_slave,
2117                                &is_spi_i2c_slave);
2118         acpi_dev_free_resource_list(&resource_list);
2119         if (!is_spi_i2c_slave)
2120                 acpi_create_platform_device(device);
2121 }
2122
2123 static int acpi_scan_attach_handler(struct acpi_device *device)
2124 {
2125         struct acpi_hardware_id *hwid;
2126         int ret = 0;
2127
2128         list_for_each_entry(hwid, &device->pnp.ids, list) {
2129                 const struct acpi_device_id *devid;
2130                 struct acpi_scan_handler *handler;
2131
2132                 handler = acpi_scan_match_handler(hwid->id, &devid);
2133                 if (handler) {
2134                         if (!handler->attach) {
2135                                 device->pnp.type.platform_id = 0;
2136                                 continue;
2137                         }
2138                         device->handler = handler;
2139                         ret = handler->attach(device, devid);
2140                         if (ret > 0)
2141                                 break;
2142
2143                         device->handler = NULL;
2144                         if (ret < 0)
2145                                 break;
2146                 }
2147         }
2148         if (!ret)
2149                 acpi_default_enumeration(device);
2150
2151         return ret;
2152 }
2153
2154 static void acpi_bus_attach(struct acpi_device *device)
2155 {
2156         struct acpi_device *child;
2157         acpi_handle ejd;
2158         int ret;
2159
2160         if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
2161                 register_dock_dependent_device(device, ejd);
2162
2163         acpi_bus_get_status(device);
2164         /* Skip devices that are not present. */
2165         if (!acpi_device_is_present(device)) {
2166                 device->flags.visited = false;
2167                 return;
2168         }
2169         if (device->handler)
2170                 goto ok;
2171
2172         if (!device->flags.initialized) {
2173                 acpi_bus_update_power(device, NULL);
2174                 device->flags.initialized = true;
2175         }
2176         device->flags.visited = false;
2177         ret = acpi_scan_attach_handler(device);
2178         if (ret < 0)
2179                 return;
2180
2181         device->flags.match_driver = true;
2182         if (!ret) {
2183                 ret = device_attach(&device->dev);
2184                 if (ret < 0)
2185                         return;
2186         }
2187         device->flags.visited = true;
2188
2189  ok:
2190         list_for_each_entry(child, &device->children, node)
2191                 acpi_bus_attach(child);
2192
2193         if (device->handler && device->handler->hotplug.notify_online)
2194                 device->handler->hotplug.notify_online(device);
2195 }
2196
2197 /**
2198  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2199  * @handle: Root of the namespace scope to scan.
2200  *
2201  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2202  * found devices.
2203  *
2204  * If no devices were found, -ENODEV is returned, but it does not mean that
2205  * there has been a real error.  There just have been no suitable ACPI objects
2206  * in the table trunk from which the kernel could create a device and add an
2207  * appropriate driver.
2208  *
2209  * Must be called under acpi_scan_lock.
2210  */
2211 int acpi_bus_scan(acpi_handle handle)
2212 {
2213         void *device = NULL;
2214
2215         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
2216                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2217                                     acpi_bus_check_add, NULL, NULL, &device);
2218
2219         if (device) {
2220                 acpi_bus_attach(device);
2221                 return 0;
2222         }
2223         return -ENODEV;
2224 }
2225 EXPORT_SYMBOL(acpi_bus_scan);
2226
2227 /**
2228  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2229  * @adev: Root of the ACPI namespace scope to walk.
2230  *
2231  * Must be called under acpi_scan_lock.
2232  */
2233 void acpi_bus_trim(struct acpi_device *adev)
2234 {
2235         struct acpi_scan_handler *handler = adev->handler;
2236         struct acpi_device *child;
2237
2238         list_for_each_entry_reverse(child, &adev->children, node)
2239                 acpi_bus_trim(child);
2240
2241         adev->flags.match_driver = false;
2242         if (handler) {
2243                 if (handler->detach)
2244                         handler->detach(adev);
2245
2246                 adev->handler = NULL;
2247         } else {
2248                 device_release_driver(&adev->dev);
2249         }
2250         /*
2251          * Most likely, the device is going away, so put it into D3cold before
2252          * that.
2253          */
2254         acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2255         adev->flags.initialized = false;
2256         adev->flags.visited = false;
2257 }
2258 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2259
2260 static int acpi_bus_scan_fixed(void)
2261 {
2262         int result = 0;
2263
2264         /*
2265          * Enumerate all fixed-feature devices.
2266          */
2267         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2268                 struct acpi_device *device = NULL;
2269
2270                 result = acpi_add_single_object(&device, NULL,
2271                                                 ACPI_BUS_TYPE_POWER_BUTTON,
2272                                                 ACPI_STA_DEFAULT);
2273                 if (result)
2274                         return result;
2275
2276                 device->flags.match_driver = true;
2277                 result = device_attach(&device->dev);
2278                 if (result < 0)
2279                         return result;
2280
2281                 device_init_wakeup(&device->dev, true);
2282         }
2283
2284         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2285                 struct acpi_device *device = NULL;
2286
2287                 result = acpi_add_single_object(&device, NULL,
2288                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2289                                                 ACPI_STA_DEFAULT);
2290                 if (result)
2291                         return result;
2292
2293                 device->flags.match_driver = true;
2294                 result = device_attach(&device->dev);
2295         }
2296
2297         return result < 0 ? result : 0;
2298 }
2299
2300 int __init acpi_scan_init(void)
2301 {
2302         int result;
2303
2304         result = bus_register(&acpi_bus_type);
2305         if (result) {
2306                 /* We don't want to quit even if we failed to add suspend/resume */
2307                 printk(KERN_ERR PREFIX "Could not register bus type\n");
2308         }
2309
2310         acpi_pci_root_init();
2311         acpi_pci_link_init();
2312         acpi_processor_init();
2313         acpi_lpss_init();
2314         acpi_cmos_rtc_init();
2315         acpi_container_init();
2316         acpi_memory_hotplug_init();
2317         acpi_pnp_init();
2318
2319         mutex_lock(&acpi_scan_lock);
2320         /*
2321          * Enumerate devices in the ACPI namespace.
2322          */
2323         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2324         if (result)
2325                 goto out;
2326
2327         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2328         if (result)
2329                 goto out;
2330
2331         /* Fixed feature devices do not exist on HW-reduced platform */
2332         if (!acpi_gbl_reduced_hardware) {
2333                 result = acpi_bus_scan_fixed();
2334                 if (result) {
2335                         acpi_detach_data(acpi_root->handle,
2336                                          acpi_scan_drop_device);
2337                         acpi_device_del(acpi_root);
2338                         put_device(&acpi_root->dev);
2339                         goto out;
2340                 }
2341         }
2342
2343         acpi_update_all_gpes();
2344
2345  out:
2346         mutex_unlock(&acpi_scan_lock);
2347         return result;
2348 }