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