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
 291         mutex_lock(&acpi_scan_lock);
 292
 293         acpi_bus_get_device(handle, &device);
 294         if (!device)
 295                 goto err_out;
 296
 297         handler = device->handler;
 298         if (!handler || !handler->hotplug.enabled) {
 299                 ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 300                 goto err_out;
 301         }
 302         acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST,
 303                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 304         if (handler->hotplug.mode == AHM_CONTAINER) {
 305                 device->flags.eject_pending = true;
 306                 kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE);
 307         } else {
 308                 int error;
 309
 310                 get_device(&device->dev);
 311                 error = acpi_scan_hot_remove(device);
 312                 if (error)
 313                         goto err_out;
 314         }
 315
 316  out:
 317         mutex_unlock(&acpi_scan_lock);
 318         return;
 319
 320  err_out:
 321         acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST, ost_code,
 322                                   NULL);
 323         goto out;
 324 }
 325
 326 static void acpi_scan_bus_device_check(acpi_handle handle, u32 ost_source)
 327 {
 328         struct acpi_device *device = NULL;
 329         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 330         int error;
 331
 332         mutex_lock(&acpi_scan_lock);
 333         lock_device_hotplug();
 334
 335         acpi_bus_get_device(handle, &device);
 336         if (device) {
 337                 dev_warn(&device->dev, "Attempt to re-insert\n");
 338                 goto out;
 339         }
 340         acpi_evaluate_hotplug_ost(handle, ost_source,
 341                                   ACPI_OST_SC_INSERT_IN_PROGRESS, NULL);
 342         error = acpi_bus_scan(handle);
 343         if (error) {
 344                 acpi_handle_warn(handle, "Namespace scan failure\n");
 345                 goto out;
 346         }
 347         error = acpi_bus_get_device(handle, &device);
 348         if (error) {
 349                 acpi_handle_warn(handle, "Missing device node object\n");
 350                 goto out;
 351         }
 352         ost_code = ACPI_OST_SC_SUCCESS;
 353         if (device->handler && device->handler->hotplug.mode == AHM_CONTAINER)
 354                 kobject_uevent(&device->dev.kobj, KOBJ_ONLINE);
 355
 356  out:
 357         unlock_device_hotplug();
 358         acpi_evaluate_hotplug_ost(handle, ost_source, ost_code, NULL);
 359         mutex_unlock(&acpi_scan_lock);
 360 }
 361
 362 static void acpi_scan_bus_check(void *context)
 363 {
 364         acpi_scan_bus_device_check((acpi_handle)context,
 365                                    ACPI_NOTIFY_BUS_CHECK);
 366 }
 367
 368 static void acpi_scan_device_check(void *context)
 369 {
 370         acpi_scan_bus_device_check((acpi_handle)context,
 371                                    ACPI_NOTIFY_DEVICE_CHECK);
 372 }
 373
 374 static void acpi_hotplug_unsupported(acpi_handle handle, u32 type)
 375 {
 376         u32 ost_status;
 377
 378         switch (type) {
 379         case ACPI_NOTIFY_BUS_CHECK:
 380                 acpi_handle_debug(handle,
 381                         "ACPI_NOTIFY_BUS_CHECK event: unsupported\n");
 382                 ost_status = ACPI_OST_SC_INSERT_NOT_SUPPORTED;
 383                 break;
 384         case ACPI_NOTIFY_DEVICE_CHECK:
 385                 acpi_handle_debug(handle,
 386                         "ACPI_NOTIFY_DEVICE_CHECK event: unsupported\n");
 387                 ost_status = ACPI_OST_SC_INSERT_NOT_SUPPORTED;
 388                 break;
 389         case ACPI_NOTIFY_EJECT_REQUEST:
 390                 acpi_handle_debug(handle,
 391                         "ACPI_NOTIFY_EJECT_REQUEST event: unsupported\n");
 392                 ost_status = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 393                 break;
 394         default:
 395                 /* non-hotplug event; possibly handled by other handler */
 396                 return;
 397         }
 398
 399         acpi_evaluate_hotplug_ost(handle, type, ost_status, NULL);
 400 }
 401
 402 static void acpi_hotplug_notify_cb(acpi_handle handle, u32 type, void *data)
 403 {
 404         acpi_osd_exec_callback callback;
 405         struct acpi_scan_handler *handler = data;
 406         acpi_status status;
 407
 408         if (!handler->hotplug.enabled)
 409                 return acpi_hotplug_unsupported(handle, type);
 410
 411         switch (type) {
 412         case ACPI_NOTIFY_BUS_CHECK:
 413                 acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
 414                 callback = acpi_scan_bus_check;
 415                 break;
 416         case ACPI_NOTIFY_DEVICE_CHECK:
 417                 acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
 418                 callback = acpi_scan_device_check;
 419                 break;
 420         case ACPI_NOTIFY_EJECT_REQUEST:
 421                 acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
 422                 callback = acpi_bus_device_eject;
 423                 break;
 424         default:
 425                 /* non-hotplug event; possibly handled by other handler */
 426                 return;
 427         }
 428         status = acpi_os_hotplug_execute(callback, handle);
 429         if (ACPI_FAILURE(status))
 430                 acpi_evaluate_hotplug_ost(handle, type,
 431                                           ACPI_OST_SC_NON_SPECIFIC_FAILURE,
 432                                           NULL);
 433 }
 434
 435 /**
 436  * acpi_bus_hot_remove_device: hot-remove a device and its children
 437  * @context: struct acpi_eject_event pointer (freed in this func)
 438  *
 439  * Hot-remove a device and its children. This function frees up the
 440  * memory space passed by arg context, so that the caller may call
 441  * this function asynchronously through acpi_os_hotplug_execute().
 442  */
 443 void acpi_bus_hot_remove_device(void *context)
 444 {
 445         struct acpi_eject_event *ej_event = context;
 446         struct acpi_device *device = ej_event->device;
 447         acpi_handle handle = device->handle;
 448         int error;
 449
 450         mutex_lock(&acpi_scan_lock);
 451
 452         error = acpi_scan_hot_remove(device);
 453         if (error && handle)
 454                 acpi_evaluate_hotplug_ost(handle, ej_event->event,
 455                                           ACPI_OST_SC_NON_SPECIFIC_FAILURE,
 456                                           NULL);
 457
 458         mutex_unlock(&acpi_scan_lock);
 459         kfree(context);
 460 }
 461 EXPORT_SYMBOL(acpi_bus_hot_remove_device);
 462
 463 static ssize_t real_power_state_show(struct device *dev,
 464                                      struct device_attribute *attr, char *buf)
 465 {
 466         struct acpi_device *adev = to_acpi_device(dev);
 467         int state;
 468         int ret;
 469
 470         ret = acpi_device_get_power(adev, &state);
 471         if (ret)
 472                 return ret;
 473
 474         return sprintf(buf, "%s\n", acpi_power_state_string(state));
 475 }
 476
 477 static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL);
 478
 479 static ssize_t power_state_show(struct device *dev,
 480                                 struct device_attribute *attr, char *buf)
 481 {
 482         struct acpi_device *adev = to_acpi_device(dev);
 483
 484         return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
 485 }
 486
 487 static DEVICE_ATTR(power_state, 0444, power_state_show, NULL);
 488
 489 static ssize_t
 490 acpi_eject_store(struct device *d, struct device_attribute *attr,
 491                 const char *buf, size_t count)
 492 {
 493         struct acpi_device *acpi_device = to_acpi_device(d);
 494         struct acpi_eject_event *ej_event;
 495         acpi_object_type not_used;
 496         acpi_status status;
 497         u32 ost_source;
 498         int ret;
 499
 500         if (!count || buf[0] != '1')
 501                 return -EINVAL;
 502
 503         if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
 504             && !acpi_device->driver)
 505                 return -ENODEV;
 506
 507         status = acpi_get_type(acpi_device->handle, &not_used);
 508         if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
 509                 return -ENODEV;
 510
 511         mutex_lock(&acpi_scan_lock);
 512
 513         if (acpi_device->flags.eject_pending) {
 514                 /* ACPI eject notification event. */
 515                 ost_source = ACPI_NOTIFY_EJECT_REQUEST;
 516                 acpi_device->flags.eject_pending = 0;
 517         } else {
 518                 /* Eject initiated by user space. */
 519                 ost_source = ACPI_OST_EC_OSPM_EJECT;
 520         }
 521         ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
 522         if (!ej_event) {
 523                 ret = -ENOMEM;
 524                 goto err_out;
 525         }
 526         acpi_evaluate_hotplug_ost(acpi_device->handle, ost_source,
 527                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 528         ej_event->device = acpi_device;
 529         ej_event->event = ost_source;
 530         get_device(&acpi_device->dev);
 531         status = acpi_os_hotplug_execute(acpi_bus_hot_remove_device, ej_event);
 532         if (ACPI_FAILURE(status)) {
 533                 put_device(&acpi_device->dev);
 534                 kfree(ej_event);
 535                 ret = status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
 536                 goto err_out;
 537         }
 538         ret = count;
 539
 540  out:
 541         mutex_unlock(&acpi_scan_lock);
 542         return ret;
 543
 544  err_out:
 545         acpi_evaluate_hotplug_ost(acpi_device->handle, ost_source,
 546                                   ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
 547         goto out;
 548 }
 549
 550 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 551
 552 static ssize_t
 553 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 554         struct acpi_device *acpi_dev = to_acpi_device(dev);
 555
 556         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
 557 }
 558 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 559
 560 static ssize_t acpi_device_uid_show(struct device *dev,
 561                                     struct device_attribute *attr, char *buf)
 562 {
 563         struct acpi_device *acpi_dev = to_acpi_device(dev);
 564
 565         return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
 566 }
 567 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
 568
 569 static ssize_t acpi_device_adr_show(struct device *dev,
 570                                     struct device_attribute *attr, char *buf)
 571 {
 572         struct acpi_device *acpi_dev = to_acpi_device(dev);
 573
 574         return sprintf(buf, "0x%08x\n",
 575                        (unsigned int)(acpi_dev->pnp.bus_address));
 576 }
 577 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
 578
 579 static ssize_t
 580 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 581         struct acpi_device *acpi_dev = to_acpi_device(dev);
 582         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 583         int result;
 584
 585         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 586         if (result)
 587                 goto end;
 588
 589         result = sprintf(buf, "%s\n", (char*)path.pointer);
 590         kfree(path.pointer);
 591 end:
 592         return result;
 593 }
 594 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 595
 596 /* sysfs file that shows description text from the ACPI _STR method */
 597 static ssize_t description_show(struct device *dev,
 598                                 struct device_attribute *attr,
 599                                 char *buf) {
 600         struct acpi_device *acpi_dev = to_acpi_device(dev);
 601         int result;
 602
 603         if (acpi_dev->pnp.str_obj == NULL)
 604                 return 0;
 605
 606         /*
 607          * The _STR object contains a Unicode identifier for a device.
 608          * We need to convert to utf-8 so it can be displayed.
 609          */
 610         result = utf16s_to_utf8s(
 611                 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
 612                 acpi_dev->pnp.str_obj->buffer.length,
 613                 UTF16_LITTLE_ENDIAN, buf,
 614                 PAGE_SIZE);
 615
 616         buf[result++] = '\n';
 617
 618         return result;
 619 }
 620 static DEVICE_ATTR(description, 0444, description_show, NULL);
 621
 622 static ssize_t
 623 acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
 624                      char *buf) {
 625         struct acpi_device *acpi_dev = to_acpi_device(dev);
 626
 627         return sprintf(buf, "%lu\n", acpi_dev->pnp.sun);
 628 }
 629 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
 630
 631 static int acpi_device_setup_files(struct acpi_device *dev)
 632 {
 633         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 634         acpi_status status;
 635         unsigned long long sun;
 636         int result = 0;
 637
 638         /*
 639          * Devices gotten from FADT don't have a "path" attribute
 640          */
 641         if (dev->handle) {
 642                 result = device_create_file(&dev->dev, &dev_attr_path);
 643                 if (result)
 644                         goto end;
 645         }
 646
 647         if (!list_empty(&dev->pnp.ids)) {
 648                 result = device_create_file(&dev->dev, &dev_attr_hid);
 649                 if (result)
 650                         goto end;
 651
 652                 result = device_create_file(&dev->dev, &dev_attr_modalias);
 653                 if (result)
 654                         goto end;
 655         }
 656
 657         /*
 658          * If device has _STR, 'description' file is created
 659          */
 660         if (acpi_has_method(dev->handle, "_STR")) {
 661                 status = acpi_evaluate_object(dev->handle, "_STR",
 662                                         NULL, &buffer);
 663                 if (ACPI_FAILURE(status))
 664                         buffer.pointer = NULL;
 665                 dev->pnp.str_obj = buffer.pointer;
 666                 result = device_create_file(&dev->dev, &dev_attr_description);
 667                 if (result)
 668                         goto end;
 669         }
 670
 671         if (dev->pnp.type.bus_address)
 672                 result = device_create_file(&dev->dev, &dev_attr_adr);
 673         if (dev->pnp.unique_id)
 674                 result = device_create_file(&dev->dev, &dev_attr_uid);
 675
 676         status = acpi_evaluate_integer(dev->handle, "_SUN", NULL, &sun);
 677         if (ACPI_SUCCESS(status)) {
 678                 dev->pnp.sun = (unsigned long)sun;
 679                 result = device_create_file(&dev->dev, &dev_attr_sun);
 680                 if (result)
 681                         goto end;
 682         } else {
 683                 dev->pnp.sun = (unsigned long)-1;
 684         }
 685
 686         /*
 687          * If device has _EJ0, 'eject' file is created that is used to trigger
 688          * hot-removal function from userland.
 689          */
 690         if (acpi_has_method(dev->handle, "_EJ0")) {
 691                 result = device_create_file(&dev->dev, &dev_attr_eject);
 692                 if (result)
 693                         return result;
 694         }
 695
 696         if (dev->flags.power_manageable) {
 697                 result = device_create_file(&dev->dev, &dev_attr_power_state);
 698                 if (result)
 699                         return result;
 700
 701                 if (dev->power.flags.power_resources)
 702                         result = device_create_file(&dev->dev,
 703                                                     &dev_attr_real_power_state);
 704         }
 705
 706 end:
 707         return result;
 708 }
 709
 710 static void acpi_device_remove_files(struct acpi_device *dev)
 711 {
 712         if (dev->flags.power_manageable) {
 713                 device_remove_file(&dev->dev, &dev_attr_power_state);
 714                 if (dev->power.flags.power_resources)
 715                         device_remove_file(&dev->dev,
 716                                            &dev_attr_real_power_state);
 717         }
 718
 719         /*
 720          * If device has _STR, remove 'description' file
 721          */
 722         if (acpi_has_method(dev->handle, "_STR")) {
 723                 kfree(dev->pnp.str_obj);
 724                 device_remove_file(&dev->dev, &dev_attr_description);
 725         }
 726         /*
 727          * If device has _EJ0, remove 'eject' file.
 728          */
 729         if (acpi_has_method(dev->handle, "_EJ0"))
 730                 device_remove_file(&dev->dev, &dev_attr_eject);
 731
 732         if (acpi_has_method(dev->handle, "_SUN"))
 733                 device_remove_file(&dev->dev, &dev_attr_sun);
 734
 735         if (dev->pnp.unique_id)
 736                 device_remove_file(&dev->dev, &dev_attr_uid);
 737         if (dev->pnp.type.bus_address)
 738                 device_remove_file(&dev->dev, &dev_attr_adr);
 739         device_remove_file(&dev->dev, &dev_attr_modalias);
 740         device_remove_file(&dev->dev, &dev_attr_hid);
 741         if (dev->handle)
 742                 device_remove_file(&dev->dev, &dev_attr_path);
 743 }
 744 /* --------------------------------------------------------------------------
 745                         ACPI Bus operations
 746    -------------------------------------------------------------------------- */
 747
 748 static const struct acpi_device_id *__acpi_match_device(
 749         struct acpi_device *device, const struct acpi_device_id *ids)
 750 {
 751         const struct acpi_device_id *id;
 752         struct acpi_hardware_id *hwid;
 753
 754         /*
 755          * If the device is not present, it is unnecessary to load device
 756          * driver for it.
 757          */
 758         if (!device->status.present)
 759                 return NULL;
 760
 761         for (id = ids; id->id[0]; id++)
 762                 list_for_each_entry(hwid, &device->pnp.ids, list)
 763                         if (!strcmp((char *) id->id, hwid->id))
 764                                 return id;
 765
 766         return NULL;
 767 }
 768
 769 /**
 770  * acpi_match_device - Match a struct device against a given list of ACPI IDs
 771  * @ids: Array of struct acpi_device_id object to match against.
 772  * @dev: The device structure to match.
 773  *
 774  * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
 775  * object for that handle and use that object to match against a given list of
 776  * device IDs.
 777  *
 778  * Return a pointer to the first matching ID on success or %NULL on failure.
 779  */
 780 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
 781                                                const struct device *dev)
 782 {
 783         struct acpi_device *adev;
 784         acpi_handle handle = ACPI_HANDLE(dev);
 785
 786         if (!ids || !handle || acpi_bus_get_device(handle, &adev))
 787                 return NULL;
 788
 789         return __acpi_match_device(adev, ids);
 790 }
 791 EXPORT_SYMBOL_GPL(acpi_match_device);
 792
 793 int acpi_match_device_ids(struct acpi_device *device,
 794                           const struct acpi_device_id *ids)
 795 {
 796         return __acpi_match_device(device, ids) ? 0 : -ENOENT;
 797 }
 798 EXPORT_SYMBOL(acpi_match_device_ids);
 799
 800 static void acpi_free_power_resources_lists(struct acpi_device *device)
 801 {
 802         int i;
 803
 804         if (device->wakeup.flags.valid)
 805                 acpi_power_resources_list_free(&device->wakeup.resources);
 806
 807         if (!device->flags.power_manageable)
 808                 return;
 809
 810         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 811                 struct acpi_device_power_state *ps = &device->power.states[i];
 812                 acpi_power_resources_list_free(&ps->resources);
 813         }
 814 }
 815
 816 static void acpi_device_release(struct device *dev)
 817 {
 818         struct acpi_device *acpi_dev = to_acpi_device(dev);
 819
 820         acpi_free_pnp_ids(&acpi_dev->pnp);
 821         acpi_free_power_resources_lists(acpi_dev);
 822         kfree(acpi_dev);
 823 }
 824
 825 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 826 {
 827         struct acpi_device *acpi_dev = to_acpi_device(dev);
 828         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 829
 830         return acpi_dev->flags.match_driver
 831                 && !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 832 }
 833
 834 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 835 {
 836         struct acpi_device *acpi_dev = to_acpi_device(dev);
 837         int len;
 838
 839         if (list_empty(&acpi_dev->pnp.ids))
 840                 return 0;
 841
 842         if (add_uevent_var(env, "MODALIAS="))
 843                 return -ENOMEM;
 844         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 845                               sizeof(env->buf) - env->buflen);
 846         if (len >= (sizeof(env->buf) - env->buflen))
 847                 return -ENOMEM;
 848         env->buflen += len;
 849         return 0;
 850 }
 851
 852 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 853 {
 854         struct acpi_device *device = data;
 855
 856         device->driver->ops.notify(device, event);
 857 }
 858
 859 static acpi_status acpi_device_notify_fixed(void *data)
 860 {
 861         struct acpi_device *device = data;
 862
 863         /* Fixed hardware devices have no handles */
 864         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 865         return AE_OK;
 866 }
 867
 868 static int acpi_device_install_notify_handler(struct acpi_device *device)
 869 {
 870         acpi_status status;
 871
 872         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 873                 status =
 874                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 875                                                      acpi_device_notify_fixed,
 876                                                      device);
 877         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 878                 status =
 879                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 880                                                      acpi_device_notify_fixed,
 881                                                      device);
 882         else
 883                 status = acpi_install_notify_handler(device->handle,
 884                                                      ACPI_DEVICE_NOTIFY,
 885                                                      acpi_device_notify,
 886                                                      device);
 887
 888         if (ACPI_FAILURE(status))
 889                 return -EINVAL;
 890         return 0;
 891 }
 892
 893 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 894 {
 895         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 896                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 897                                                 acpi_device_notify_fixed);
 898         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 899                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 900                                                 acpi_device_notify_fixed);
 901         else
 902                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 903                                            acpi_device_notify);
 904 }
 905
 906 static int acpi_device_probe(struct device *dev)
 907 {
 908         struct acpi_device *acpi_dev = to_acpi_device(dev);
 909         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 910         int ret;
 911
 912         if (acpi_dev->handler)
 913                 return -EINVAL;
 914
 915         if (!acpi_drv->ops.add)
 916                 return -ENOSYS;
 917
 918         ret = acpi_drv->ops.add(acpi_dev);
 919         if (ret)
 920                 return ret;
 921
 922         acpi_dev->driver = acpi_drv;
 923         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 924                           "Driver [%s] successfully bound to device [%s]\n",
 925                           acpi_drv->name, acpi_dev->pnp.bus_id));
 926
 927         if (acpi_drv->ops.notify) {
 928                 ret = acpi_device_install_notify_handler(acpi_dev);
 929                 if (ret) {
 930                         if (acpi_drv->ops.remove)
 931                                 acpi_drv->ops.remove(acpi_dev);
 932
 933                         acpi_dev->driver = NULL;
 934                         acpi_dev->driver_data = NULL;
 935                         return ret;
 936                 }
 937         }
 938
 939         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
 940                           acpi_drv->name, acpi_dev->pnp.bus_id));
 941         get_device(dev);
 942         return 0;
 943 }
 944
 945 static int acpi_device_remove(struct device * dev)
 946 {
 947         struct acpi_device *acpi_dev = to_acpi_device(dev);
 948         struct acpi_driver *acpi_drv = acpi_dev->driver;
 949
 950         if (acpi_drv) {
 951                 if (acpi_drv->ops.notify)
 952                         acpi_device_remove_notify_handler(acpi_dev);
 953                 if (acpi_drv->ops.remove)
 954                         acpi_drv->ops.remove(acpi_dev);
 955         }
 956         acpi_dev->driver = NULL;
 957         acpi_dev->driver_data = NULL;
 958
 959         put_device(dev);
 960         return 0;
 961 }
 962
 963 struct bus_type acpi_bus_type = {
 964         .name           = "acpi",
 965         .match          = acpi_bus_match,
 966         .probe          = acpi_device_probe,
 967         .remove         = acpi_device_remove,
 968         .uevent         = acpi_device_uevent,
 969 };
 970
 971 int acpi_device_add(struct acpi_device *device,
 972                     void (*release)(struct device *))
 973 {
 974         int result;
 975         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 976         int found = 0;
 977
 978         if (device->handle) {
 979                 acpi_status status;
 980
 981                 status = acpi_attach_data(device->handle, acpi_bus_data_handler,
 982                                           device);
 983                 if (ACPI_FAILURE(status)) {
 984                         acpi_handle_err(device->handle,
 985                                         "Unable to attach device data\n");
 986                         return -ENODEV;
 987                 }
 988         }
 989
 990         /*
 991          * Linkage
 992          * -------
 993          * Link this device to its parent and siblings.
 994          */
 995         INIT_LIST_HEAD(&device->children);
 996         INIT_LIST_HEAD(&device->node);
 997         INIT_LIST_HEAD(&device->wakeup_list);
 998         INIT_LIST_HEAD(&device->physical_node_list);
 999         mutex_init(&device->physical_node_lock);
1000         INIT_LIST_HEAD(&device->power_dependent);
1001
1002         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
1003         if (!new_bus_id) {
1004                 pr_err(PREFIX "Memory allocation error\n");
1005                 result = -ENOMEM;
1006                 goto err_detach;
1007         }
1008
1009         mutex_lock(&acpi_device_lock);
1010         /*
1011          * Find suitable bus_id and instance number in acpi_bus_id_list
1012          * If failed, create one and link it into acpi_bus_id_list
1013          */
1014         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
1015                 if (!strcmp(acpi_device_bus_id->bus_id,
1016                             acpi_device_hid(device))) {
1017                         acpi_device_bus_id->instance_no++;
1018                         found = 1;
1019                         kfree(new_bus_id);
1020                         break;
1021                 }
1022         }
1023         if (!found) {
1024                 acpi_device_bus_id = new_bus_id;
1025                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
1026                 acpi_device_bus_id->instance_no = 0;
1027                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
1028         }
1029         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
1030
1031         if (device->parent)
1032                 list_add_tail(&device->node, &device->parent->children);
1033
1034         if (device->wakeup.flags.valid)
1035                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
1036         mutex_unlock(&acpi_device_lock);
1037
1038         if (device->parent)
1039                 device->dev.parent = &device->parent->dev;
1040         device->dev.bus = &acpi_bus_type;
1041         device->dev.release = release;
1042         result = device_add(&device->dev);
1043         if (result) {
1044                 dev_err(&device->dev, "Error registering device\n");
1045                 goto err;
1046         }
1047
1048         result = acpi_device_setup_files(device);
1049         if (result)
1050                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
1051                        dev_name(&device->dev));
1052
1053         return 0;
1054
1055  err:
1056         mutex_lock(&acpi_device_lock);
1057         if (device->parent)
1058                 list_del(&device->node);
1059         list_del(&device->wakeup_list);
1060         mutex_unlock(&acpi_device_lock);
1061
1062  err_detach:
1063         acpi_detach_data(device->handle, acpi_bus_data_handler);
1064         return result;
1065 }
1066
1067 static void acpi_device_unregister(struct acpi_device *device)
1068 {
1069         mutex_lock(&acpi_device_lock);
1070         if (device->parent)
1071                 list_del(&device->node);
1072
1073         list_del(&device->wakeup_list);
1074         mutex_unlock(&acpi_device_lock);
1075
1076         acpi_detach_data(device->handle, acpi_bus_data_handler);
1077
1078         acpi_power_add_remove_device(device, false);
1079         acpi_device_remove_files(device);
1080         if (device->remove)
1081                 device->remove(device);
1082
1083         device_del(&device->dev);
1084         /*
1085          * Transition the device to D3cold to drop the reference counts of all
1086          * power resources the device depends on and turn off the ones that have
1087          * no more references.
1088          */
1089         acpi_device_set_power(device, ACPI_STATE_D3_COLD);
1090         device->handle = NULL;
1091         put_device(&device->dev);
1092 }
1093
1094 /* --------------------------------------------------------------------------
1095                                  Driver Management
1096    -------------------------------------------------------------------------- */
1097 /**
1098  * acpi_bus_register_driver - register a driver with the ACPI bus
1099  * @driver: driver being registered
1100  *
1101  * Registers a driver with the ACPI bus.  Searches the namespace for all
1102  * devices that match the driver's criteria and binds.  Returns zero for
1103  * success or a negative error status for failure.
1104  */
1105 int acpi_bus_register_driver(struct acpi_driver *driver)
1106 {
1107         int ret;
1108
1109         if (acpi_disabled)
1110                 return -ENODEV;
1111         driver->drv.name = driver->name;
1112         driver->drv.bus = &acpi_bus_type;
1113         driver->drv.owner = driver->owner;
1114
1115         ret = driver_register(&driver->drv);
1116         return ret;
1117 }
1118
1119 EXPORT_SYMBOL(acpi_bus_register_driver);
1120
1121 /**
1122  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
1123  * @driver: driver to unregister
1124  *
1125  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
1126  * devices that match the driver's criteria and unbinds.
1127  */
1128 void acpi_bus_unregister_driver(struct acpi_driver *driver)
1129 {
1130         driver_unregister(&driver->drv);
1131 }
1132
1133 EXPORT_SYMBOL(acpi_bus_unregister_driver);
1134
1135 /* --------------------------------------------------------------------------
1136                                  Device Enumeration
1137    -------------------------------------------------------------------------- */
1138 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
1139 {
1140         struct acpi_device *device = NULL;
1141         acpi_status status;
1142
1143         /*
1144          * Fixed hardware devices do not appear in the namespace and do not
1145          * have handles, but we fabricate acpi_devices for them, so we have
1146          * to deal with them specially.
1147          */
1148         if (!handle)
1149                 return acpi_root;
1150
1151         do {
1152                 status = acpi_get_parent(handle, &handle);
1153                 if (ACPI_FAILURE(status))
1154                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
1155         } while (acpi_bus_get_device(handle, &device));
1156         return device;
1157 }
1158
1159 acpi_status
1160 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
1161 {
1162         acpi_status status;
1163         acpi_handle tmp;
1164         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
1165         union acpi_object *obj;
1166
1167         status = acpi_get_handle(handle, "_EJD", &tmp);
1168         if (ACPI_FAILURE(status))
1169                 return status;
1170
1171         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
1172         if (ACPI_SUCCESS(status)) {
1173                 obj = buffer.pointer;
1174                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
1175                                          ejd);
1176                 kfree(buffer.pointer);
1177         }
1178         return status;
1179 }
1180 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
1181
1182 void acpi_bus_data_handler(acpi_handle handle, void *context)
1183 {
1184
1185         /* TBD */
1186
1187         return;
1188 }
1189
1190 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
1191                                         struct acpi_device_wakeup *wakeup)
1192 {
1193         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1194         union acpi_object *package = NULL;
1195         union acpi_object *element = NULL;
1196         acpi_status status;
1197         int err = -ENODATA;
1198
1199         if (!wakeup)
1200                 return -EINVAL;
1201
1202         INIT_LIST_HEAD(&wakeup->resources);
1203
1204         /* _PRW */
1205         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
1206         if (ACPI_FAILURE(status)) {
1207                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
1208                 return err;
1209         }
1210
1211         package = (union acpi_object *)buffer.pointer;
1212
1213         if (!package || package->package.count < 2)
1214                 goto out;
1215
1216         element = &(package->package.elements[0]);
1217         if (!element)
1218                 goto out;
1219
1220         if (element->type == ACPI_TYPE_PACKAGE) {
1221                 if ((element->package.count < 2) ||
1222                     (element->package.elements[0].type !=
1223                      ACPI_TYPE_LOCAL_REFERENCE)
1224                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
1225                         goto out;
1226
1227                 wakeup->gpe_device =
1228                     element->package.elements[0].reference.handle;
1229                 wakeup->gpe_number =
1230                     (u32) element->package.elements[1].integer.value;
1231         } else if (element->type == ACPI_TYPE_INTEGER) {
1232                 wakeup->gpe_device = NULL;
1233                 wakeup->gpe_number = element->integer.value;
1234         } else {
1235                 goto out;
1236         }
1237
1238         element = &(package->package.elements[1]);
1239         if (element->type != ACPI_TYPE_INTEGER)
1240                 goto out;
1241
1242         wakeup->sleep_state = element->integer.value;
1243
1244         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
1245         if (err)
1246                 goto out;
1247
1248         if (!list_empty(&wakeup->resources)) {
1249                 int sleep_state;
1250
1251                 err = acpi_power_wakeup_list_init(&wakeup->resources,
1252                                                   &sleep_state);
1253                 if (err) {
1254                         acpi_handle_warn(handle, "Retrieving current states "
1255                                          "of wakeup power resources failed\n");
1256                         acpi_power_resources_list_free(&wakeup->resources);
1257                         goto out;
1258                 }
1259                 if (sleep_state < wakeup->sleep_state) {
1260                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
1261                                          "(S%d) by S%d from power resources\n",
1262                                          (int)wakeup->sleep_state, sleep_state);
1263                         wakeup->sleep_state = sleep_state;
1264                 }
1265         }
1266         acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
1267
1268  out:
1269         kfree(buffer.pointer);
1270         return err;
1271 }
1272
1273 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
1274 {
1275         struct acpi_device_id button_device_ids[] = {
1276                 {"PNP0C0C", 0},
1277                 {"PNP0C0D", 0},
1278                 {"PNP0C0E", 0},
1279                 {"", 0},
1280         };
1281         acpi_status status;
1282         acpi_event_status event_status;
1283
1284         device->wakeup.flags.notifier_present = 0;
1285
1286         /* Power button, Lid switch always enable wakeup */
1287         if (!acpi_match_device_ids(device, button_device_ids)) {
1288                 device->wakeup.flags.run_wake = 1;
1289                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
1290                         /* Do not use Lid/sleep button for S5 wakeup */
1291                         if (device->wakeup.sleep_state == ACPI_STATE_S5)
1292                                 device->wakeup.sleep_state = ACPI_STATE_S4;
1293                 }
1294                 device_set_wakeup_capable(&device->dev, true);
1295                 return;
1296         }
1297
1298         status = acpi_get_gpe_status(device->wakeup.gpe_device,
1299                                         device->wakeup.gpe_number,
1300                                                 &event_status);
1301         if (status == AE_OK)
1302                 device->wakeup.flags.run_wake =
1303                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
1304 }
1305
1306 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1307 {
1308         int err;
1309
1310         /* Presence of _PRW indicates wake capable */
1311         if (!acpi_has_method(device->handle, "_PRW"))
1312                 return;
1313
1314         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
1315                                                            &device->wakeup);
1316         if (err) {
1317                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
1318                 return;
1319         }
1320
1321         device->wakeup.flags.valid = 1;
1322         device->wakeup.prepare_count = 0;
1323         acpi_bus_set_run_wake_flags(device);
1324         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
1325          * system for the ACPI device with the _PRW object.
1326          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
1327          * So it is necessary to call _DSW object first. Only when it is not
1328          * present will the _PSW object used.
1329          */
1330         err = acpi_device_sleep_wake(device, 0, 0, 0);
1331         if (err)
1332                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1333                                 "error in _DSW or _PSW evaluation\n"));
1334 }
1335
1336 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1337 {
1338         struct acpi_device_power_state *ps = &device->power.states[state];
1339         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1340         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1341         acpi_status status;
1342
1343         INIT_LIST_HEAD(&ps->resources);
1344
1345         /* Evaluate "_PRx" to get referenced power resources */
1346         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1347         if (ACPI_SUCCESS(status)) {
1348                 union acpi_object *package = buffer.pointer;
1349
1350                 if (buffer.length && package
1351                     && package->type == ACPI_TYPE_PACKAGE
1352                     && package->package.count) {
1353                         int err = acpi_extract_power_resources(package, 0,
1354                                                                &ps->resources);
1355                         if (!err)
1356                                 device->power.flags.power_resources = 1;
1357                 }
1358                 ACPI_FREE(buffer.pointer);
1359         }
1360
1361         /* Evaluate "_PSx" to see if we can do explicit sets */
1362         pathname[2] = 'S';
1363         if (acpi_has_method(device->handle, pathname))
1364                 ps->flags.explicit_set = 1;
1365
1366         /*
1367          * State is valid if there are means to put the device into it.
1368          * D3hot is only valid if _PR3 present.
1369          */
1370         if (!list_empty(&ps->resources)
1371             || (ps->flags.explicit_set && state < ACPI_STATE_D3_HOT)) {
1372                 ps->flags.valid = 1;
1373                 ps->flags.os_accessible = 1;
1374         }
1375
1376         ps->power = -1;         /* Unknown - driver assigned */
1377         ps->latency = -1;       /* Unknown - driver assigned */
1378 }
1379
1380 static void acpi_bus_get_power_flags(struct acpi_device *device)
1381 {
1382         u32 i;
1383
1384         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1385         if (!acpi_has_method(device->handle, "_PS0") &&
1386             !acpi_has_method(device->handle, "_PR0"))
1387                 return;
1388
1389         device->flags.power_manageable = 1;
1390
1391         /*
1392          * Power Management Flags
1393          */
1394         if (acpi_has_method(device->handle, "_PSC"))
1395                 device->power.flags.explicit_get = 1;
1396         if (acpi_has_method(device->handle, "_IRC"))
1397                 device->power.flags.inrush_current = 1;
1398
1399         /*
1400          * Enumerate supported power management states
1401          */
1402         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1403                 acpi_bus_init_power_state(device, i);
1404
1405         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1406
1407         /* Set defaults for D0 and D3 states (always valid) */
1408         device->power.states[ACPI_STATE_D0].flags.valid = 1;
1409         device->power.states[ACPI_STATE_D0].power = 100;
1410         device->power.states[ACPI_STATE_D3].flags.valid = 1;
1411         device->power.states[ACPI_STATE_D3].power = 0;
1412
1413         /* Set D3cold's explicit_set flag if _PS3 exists. */
1414         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
1415                 device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
1416
1417         /* Presence of _PS3 or _PRx means we can put the device into D3 cold */
1418         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set ||
1419                         device->power.flags.power_resources)
1420                 device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
1421
1422         if (acpi_bus_init_power(device)) {
1423                 acpi_free_power_resources_lists(device);
1424                 device->flags.power_manageable = 0;
1425         }
1426 }
1427
1428 static void acpi_bus_get_flags(struct acpi_device *device)
1429 {
1430         /* Presence of _STA indicates 'dynamic_status' */
1431         if (acpi_has_method(device->handle, "_STA"))
1432                 device->flags.dynamic_status = 1;
1433
1434         /* Presence of _RMV indicates 'removable' */
1435         if (acpi_has_method(device->handle, "_RMV"))
1436                 device->flags.removable = 1;
1437
1438         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1439         if (acpi_has_method(device->handle, "_EJD") ||
1440             acpi_has_method(device->handle, "_EJ0"))
1441                 device->flags.ejectable = 1;
1442 }
1443
1444 static void acpi_device_get_busid(struct acpi_device *device)
1445 {
1446         char bus_id[5] = { '?', 0 };
1447         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1448         int i = 0;
1449
1450         /*
1451          * Bus ID
1452          * ------
1453          * The device's Bus ID is simply the object name.
1454          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1455          */
1456         if (ACPI_IS_ROOT_DEVICE(device)) {
1457                 strcpy(device->pnp.bus_id, "ACPI");
1458                 return;
1459         }
1460
1461         switch (device->device_type) {
1462         case ACPI_BUS_TYPE_POWER_BUTTON:
1463                 strcpy(device->pnp.bus_id, "PWRF");
1464                 break;
1465         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1466                 strcpy(device->pnp.bus_id, "SLPF");
1467                 break;
1468         default:
1469                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1470                 /* Clean up trailing underscores (if any) */
1471                 for (i = 3; i > 1; i--) {
1472                         if (bus_id[i] == '_')
1473                                 bus_id[i] = '\0';
1474                         else
1475                                 break;
1476                 }
1477                 strcpy(device->pnp.bus_id, bus_id);
1478                 break;
1479         }
1480 }
1481
1482 /*
1483  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1484  *
1485  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1486  * then we can safely call it an ejectable drive bay
1487  */
1488 static int acpi_bay_match(acpi_handle handle)
1489 {
1490         acpi_handle phandle;
1491
1492         if (!acpi_has_method(handle, "_EJ0"))
1493                 return -ENODEV;
1494
1495         if (acpi_has_method(handle, "_GTF") ||
1496             acpi_has_method(handle, "_GTM") ||
1497             acpi_has_method(handle, "_STM") ||
1498             acpi_has_method(handle, "_SDD"))
1499                 return 0;
1500
1501         if (acpi_get_parent(handle, &phandle))
1502                 return -ENODEV;
1503
1504         if (acpi_has_method(phandle, "_GTF") ||
1505             acpi_has_method(phandle, "_GTM") ||
1506             acpi_has_method(phandle, "_STM") ||
1507             acpi_has_method(phandle, "_SDD"))
1508                 return 0;
1509
1510         return -ENODEV;
1511 }
1512
1513 /*
1514  * acpi_dock_match - see if an acpi object has a _DCK method
1515  */
1516 static int acpi_dock_match(acpi_handle handle)
1517 {
1518         acpi_handle tmp;
1519         return acpi_get_handle(handle, "_DCK", &tmp);
1520 }
1521
1522 const char *acpi_device_hid(struct acpi_device *device)
1523 {
1524         struct acpi_hardware_id *hid;
1525
1526         if (list_empty(&device->pnp.ids))
1527                 return dummy_hid;
1528
1529         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1530         return hid->id;
1531 }
1532 EXPORT_SYMBOL(acpi_device_hid);
1533
1534 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1535 {
1536         struct acpi_hardware_id *id;
1537
1538         id = kmalloc(sizeof(*id), GFP_KERNEL);
1539         if (!id)
1540                 return;
1541
1542         id->id = kstrdup(dev_id, GFP_KERNEL);
1543         if (!id->id) {
1544                 kfree(id);
1545                 return;
1546         }
1547
1548         list_add_tail(&id->list, &pnp->ids);
1549         pnp->type.hardware_id = 1;
1550 }
1551
1552 /*
1553  * Old IBM workstations have a DSDT bug wherein the SMBus object
1554  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1555  * prefix.  Work around this.
1556  */
1557 static int acpi_ibm_smbus_match(acpi_handle handle)
1558 {
1559         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1560         int result;
1561
1562         if (!dmi_name_in_vendors("IBM"))
1563                 return -ENODEV;
1564
1565         /* Look for SMBS object */
1566         result = acpi_get_name(handle, ACPI_SINGLE_NAME, &path);
1567         if (result)
1568                 return result;
1569
1570         if (strcmp("SMBS", path.pointer)) {
1571                 result = -ENODEV;
1572                 goto out;
1573         }
1574
1575         /* Does it have the necessary (but misnamed) methods? */
1576         result = -ENODEV;
1577         if (acpi_has_method(handle, "SBI") &&
1578             acpi_has_method(handle, "SBR") &&
1579             acpi_has_method(handle, "SBW"))
1580                 result = 0;
1581 out:
1582         kfree(path.pointer);
1583         return result;
1584 }
1585
1586 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1587                                 int device_type)
1588 {
1589         acpi_status status;
1590         struct acpi_device_info *info;
1591         struct acpi_pnp_device_id_list *cid_list;
1592         int i;
1593
1594         switch (device_type) {
1595         case ACPI_BUS_TYPE_DEVICE:
1596                 if (handle == ACPI_ROOT_OBJECT) {
1597                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1598                         break;
1599                 }
1600
1601                 status = acpi_get_object_info(handle, &info);
1602                 if (ACPI_FAILURE(status)) {
1603                         pr_err(PREFIX "%s: Error reading device info\n",
1604                                         __func__);
1605                         return;
1606                 }
1607
1608                 if (info->valid & ACPI_VALID_HID)
1609                         acpi_add_id(pnp, info->hardware_id.string);
1610                 if (info->valid & ACPI_VALID_CID) {
1611                         cid_list = &info->compatible_id_list;
1612                         for (i = 0; i < cid_list->count; i++)
1613                                 acpi_add_id(pnp, cid_list->ids[i].string);
1614                 }
1615                 if (info->valid & ACPI_VALID_ADR) {
1616                         pnp->bus_address = info->address;
1617                         pnp->type.bus_address = 1;
1618                 }
1619                 if (info->valid & ACPI_VALID_UID)
1620                         pnp->unique_id = kstrdup(info->unique_id.string,
1621                                                         GFP_KERNEL);
1622
1623                 kfree(info);
1624
1625                 /*
1626                  * Some devices don't reliably have _HIDs & _CIDs, so add
1627                  * synthetic HIDs to make sure drivers can find them.
1628                  */
1629                 if (acpi_is_video_device(handle))
1630                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1631                 else if (ACPI_SUCCESS(acpi_bay_match(handle)))
1632                         acpi_add_id(pnp, ACPI_BAY_HID);
1633                 else if (ACPI_SUCCESS(acpi_dock_match(handle)))
1634                         acpi_add_id(pnp, ACPI_DOCK_HID);
1635                 else if (!acpi_ibm_smbus_match(handle))
1636                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1637                 else if (list_empty(&pnp->ids) && handle == ACPI_ROOT_OBJECT) {
1638                         acpi_add_id(pnp, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1639                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1640                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1641                 }
1642
1643                 break;
1644         case ACPI_BUS_TYPE_POWER:
1645                 acpi_add_id(pnp, ACPI_POWER_HID);
1646                 break;
1647         case ACPI_BUS_TYPE_PROCESSOR:
1648                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1649                 break;
1650         case ACPI_BUS_TYPE_THERMAL:
1651                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1652                 break;
1653         case ACPI_BUS_TYPE_POWER_BUTTON:
1654                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1655                 break;
1656         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1657                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1658                 break;
1659         }
1660 }
1661
1662 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1663 {
1664         struct acpi_hardware_id *id, *tmp;
1665
1666         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1667                 kfree(id->id);
1668                 kfree(id);
1669         }
1670         kfree(pnp->unique_id);
1671 }
1672
1673 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1674                              int type, unsigned long long sta)
1675 {
1676         INIT_LIST_HEAD(&device->pnp.ids);
1677         device->device_type = type;
1678         device->handle = handle;
1679         device->parent = acpi_bus_get_parent(handle);
1680         STRUCT_TO_INT(device->status) = sta;
1681         acpi_device_get_busid(device);
1682         acpi_set_pnp_ids(handle, &device->pnp, type);
1683         acpi_bus_get_flags(device);
1684         device->flags.match_driver = false;
1685         device_initialize(&device->dev);
1686         dev_set_uevent_suppress(&device->dev, true);
1687 }
1688
1689 void acpi_device_add_finalize(struct acpi_device *device)
1690 {
1691         device->flags.match_driver = true;
1692         dev_set_uevent_suppress(&device->dev, false);
1693         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1694 }
1695
1696 static int acpi_add_single_object(struct acpi_device **child,
1697                                   acpi_handle handle, int type,
1698                                   unsigned long long sta)
1699 {
1700         int result;
1701         struct acpi_device *device;
1702         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1703
1704         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1705         if (!device) {
1706                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1707                 return -ENOMEM;
1708         }
1709
1710         acpi_init_device_object(device, handle, type, sta);
1711         acpi_bus_get_power_flags(device);
1712         acpi_bus_get_wakeup_device_flags(device);
1713
1714         result = acpi_device_add(device, acpi_device_release);
1715         if (result) {
1716                 acpi_device_release(&device->dev);
1717                 return result;
1718         }
1719
1720         acpi_power_add_remove_device(device, true);
1721         acpi_device_add_finalize(device);
1722         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1723         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1724                 dev_name(&device->dev), (char *) buffer.pointer,
1725                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1726         kfree(buffer.pointer);
1727         *child = device;
1728         return 0;
1729 }
1730
1731 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1732                                     unsigned long long *sta)
1733 {
1734         acpi_status status;
1735         acpi_object_type acpi_type;
1736
1737         status = acpi_get_type(handle, &acpi_type);
1738         if (ACPI_FAILURE(status))
1739                 return -ENODEV;
1740
1741         switch (acpi_type) {
1742         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1743         case ACPI_TYPE_DEVICE:
1744                 *type = ACPI_BUS_TYPE_DEVICE;
1745                 status = acpi_bus_get_status_handle(handle, sta);
1746                 if (ACPI_FAILURE(status))
1747                         return -ENODEV;
1748                 break;
1749         case ACPI_TYPE_PROCESSOR:
1750                 *type = ACPI_BUS_TYPE_PROCESSOR;
1751                 status = acpi_bus_get_status_handle(handle, sta);
1752                 if (ACPI_FAILURE(status))
1753                         return -ENODEV;
1754                 break;
1755         case ACPI_TYPE_THERMAL:
1756                 *type = ACPI_BUS_TYPE_THERMAL;
1757                 *sta = ACPI_STA_DEFAULT;
1758                 break;
1759         case ACPI_TYPE_POWER:
1760                 *type = ACPI_BUS_TYPE_POWER;
1761                 *sta = ACPI_STA_DEFAULT;
1762                 break;
1763         default:
1764                 return -ENODEV;
1765         }
1766
1767         return 0;
1768 }
1769
1770 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1771                                        char *idstr,
1772                                        const struct acpi_device_id **matchid)
1773 {
1774         const struct acpi_device_id *devid;
1775
1776         for (devid = handler->ids; devid->id[0]; devid++)
1777                 if (!strcmp((char *)devid->id, idstr)) {
1778                         if (matchid)
1779                                 *matchid = devid;
1780
1781                         return true;
1782                 }
1783
1784         return false;
1785 }
1786
1787 static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr,
1788                                         const struct acpi_device_id **matchid)
1789 {
1790         struct acpi_scan_handler *handler;
1791
1792         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1793                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1794                         return handler;
1795
1796         return NULL;
1797 }
1798
1799 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1800 {
1801         if (!!hotplug->enabled == !!val)
1802                 return;
1803
1804         mutex_lock(&acpi_scan_lock);
1805
1806         hotplug->enabled = val;
1807
1808         mutex_unlock(&acpi_scan_lock);
1809 }
1810
1811 static void acpi_scan_init_hotplug(acpi_handle handle, int type)
1812 {
1813         struct acpi_device_pnp pnp = {};
1814         struct acpi_hardware_id *hwid;
1815         struct acpi_scan_handler *handler;
1816
1817         INIT_LIST_HEAD(&pnp.ids);
1818         acpi_set_pnp_ids(handle, &pnp, type);
1819
1820         if (!pnp.type.hardware_id)
1821                 goto out;
1822
1823         /*
1824          * This relies on the fact that acpi_install_notify_handler() will not
1825          * install the same notify handler routine twice for the same handle.
1826          */
1827         list_for_each_entry(hwid, &pnp.ids, list) {
1828                 handler = acpi_scan_match_handler(hwid->id, NULL);
1829                 if (handler) {
1830                         acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
1831                                         acpi_hotplug_notify_cb, handler);
1832                         break;
1833                 }
1834         }
1835
1836 out:
1837         acpi_free_pnp_ids(&pnp);
1838 }
1839
1840 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1841                                       void *not_used, void **return_value)
1842 {
1843         struct acpi_device *device = NULL;
1844         int type;
1845         unsigned long long sta;
1846         int result;
1847
1848         acpi_bus_get_device(handle, &device);
1849         if (device)
1850                 goto out;
1851
1852         result = acpi_bus_type_and_status(handle, &type, &sta);
1853         if (result)
1854                 return AE_OK;
1855
1856         if (type == ACPI_BUS_TYPE_POWER) {
1857                 acpi_add_power_resource(handle);
1858                 return AE_OK;
1859         }
1860
1861         acpi_scan_init_hotplug(handle, type);
1862
1863         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1864             !(sta & ACPI_STA_DEVICE_FUNCTIONING)) {
1865                 struct acpi_device_wakeup wakeup;
1866
1867                 if (acpi_has_method(handle, "_PRW")) {
1868                         acpi_bus_extract_wakeup_device_power_package(handle,
1869                                                                      &wakeup);
1870                         acpi_power_resources_list_free(&wakeup.resources);
1871                 }
1872                 return AE_CTRL_DEPTH;
1873         }
1874
1875         acpi_add_single_object(&device, handle, type, sta);
1876         if (!device)
1877                 return AE_CTRL_DEPTH;
1878
1879  out:
1880         if (!*return_value)
1881                 *return_value = device;
1882
1883         return AE_OK;
1884 }
1885
1886 static int acpi_scan_attach_handler(struct acpi_device *device)
1887 {
1888         struct acpi_hardware_id *hwid;
1889         int ret = 0;
1890
1891         list_for_each_entry(hwid, &device->pnp.ids, list) {
1892                 const struct acpi_device_id *devid;
1893                 struct acpi_scan_handler *handler;
1894
1895                 handler = acpi_scan_match_handler(hwid->id, &devid);
1896                 if (handler) {
1897                         ret = handler->attach(device, devid);
1898                         if (ret > 0) {
1899                                 device->handler = handler;
1900                                 break;
1901                         } else if (ret < 0) {
1902                                 break;
1903                         }
1904                 }
1905         }
1906         return ret;
1907 }
1908
1909 static acpi_status acpi_bus_device_attach(acpi_handle handle, u32 lvl_not_used,
1910                                           void *not_used, void **ret_not_used)
1911 {
1912         struct acpi_device *device;
1913         unsigned long long sta_not_used;
1914         int ret;
1915
1916         /*
1917          * Ignore errors ignored by acpi_bus_check_add() to avoid terminating
1918          * namespace walks prematurely.
1919          */
1920         if (acpi_bus_type_and_status(handle, &ret, &sta_not_used))
1921                 return AE_OK;
1922
1923         if (acpi_bus_get_device(handle, &device))
1924                 return AE_CTRL_DEPTH;
1925
1926         ret = acpi_scan_attach_handler(device);
1927         if (ret)
1928                 return ret > 0 ? AE_OK : AE_CTRL_DEPTH;
1929
1930         ret = device_attach(&device->dev);
1931         return ret >= 0 ? AE_OK : AE_CTRL_DEPTH;
1932 }
1933
1934 /**
1935  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
1936  * @handle: Root of the namespace scope to scan.
1937  *
1938  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
1939  * found devices.
1940  *
1941  * If no devices were found, -ENODEV is returned, but it does not mean that
1942  * there has been a real error.  There just have been no suitable ACPI objects
1943  * in the table trunk from which the kernel could create a device and add an
1944  * appropriate driver.
1945  *
1946  * Must be called under acpi_scan_lock.
1947  */
1948 int acpi_bus_scan(acpi_handle handle)
1949 {
1950         void *device = NULL;
1951         int error = 0;
1952
1953         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
1954                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1955                                     acpi_bus_check_add, NULL, NULL, &device);
1956
1957         if (!device)
1958                 error = -ENODEV;
1959         else if (ACPI_SUCCESS(acpi_bus_device_attach(handle, 0, NULL, NULL)))
1960                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1961                                     acpi_bus_device_attach, NULL, NULL, NULL);
1962
1963         return error;
1964 }
1965 EXPORT_SYMBOL(acpi_bus_scan);
1966
1967 static acpi_status acpi_bus_device_detach(acpi_handle handle, u32 lvl_not_used,
1968                                           void *not_used, void **ret_not_used)
1969 {
1970         struct acpi_device *device = NULL;
1971
1972         if (!acpi_bus_get_device(handle, &device)) {
1973                 struct acpi_scan_handler *dev_handler = device->handler;
1974
1975                 if (dev_handler) {
1976                         if (dev_handler->detach)
1977                                 dev_handler->detach(device);
1978
1979                         device->handler = NULL;
1980                 } else {
1981                         device_release_driver(&device->dev);
1982                 }
1983         }
1984         return AE_OK;
1985 }
1986
1987 static acpi_status acpi_bus_remove(acpi_handle handle, u32 lvl_not_used,
1988                                    void *not_used, void **ret_not_used)
1989 {
1990         struct acpi_device *device = NULL;
1991
1992         if (!acpi_bus_get_device(handle, &device))
1993                 acpi_device_unregister(device);
1994
1995         return AE_OK;
1996 }
1997
1998 /**
1999  * acpi_bus_trim - Remove ACPI device node and all of its descendants
2000  * @start: Root of the ACPI device nodes subtree to remove.
2001  *
2002  * Must be called under acpi_scan_lock.
2003  */
2004 void acpi_bus_trim(struct acpi_device *start)
2005 {
2006         /*
2007          * Execute acpi_bus_device_detach() as a post-order callback to detach
2008          * all ACPI drivers from the device nodes being removed.
2009          */
2010         acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
2011                             acpi_bus_device_detach, NULL, NULL);
2012         acpi_bus_device_detach(start->handle, 0, NULL, NULL);
2013         /*
2014          * Execute acpi_bus_remove() as a post-order callback to remove device
2015          * nodes in the given namespace scope.
2016          */
2017         acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
2018                             acpi_bus_remove, NULL, NULL);
2019         acpi_bus_remove(start->handle, 0, NULL, NULL);
2020 }
2021 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2022
2023 static int acpi_bus_scan_fixed(void)
2024 {
2025         int result = 0;
2026
2027         /*
2028          * Enumerate all fixed-feature devices.
2029          */
2030         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2031                 struct acpi_device *device = NULL;
2032
2033                 result = acpi_add_single_object(&device, NULL,
2034                                                 ACPI_BUS_TYPE_POWER_BUTTON,
2035                                                 ACPI_STA_DEFAULT);
2036                 if (result)
2037                         return result;
2038
2039                 result = device_attach(&device->dev);
2040                 if (result < 0)
2041                         return result;
2042
2043                 device_init_wakeup(&device->dev, true);
2044         }
2045
2046         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2047                 struct acpi_device *device = NULL;
2048
2049                 result = acpi_add_single_object(&device, NULL,
2050                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2051                                                 ACPI_STA_DEFAULT);
2052                 if (result)
2053                         return result;
2054
2055                 result = device_attach(&device->dev);
2056         }
2057
2058         return result < 0 ? result : 0;
2059 }
2060
2061 int __init acpi_scan_init(void)
2062 {
2063         int result;
2064
2065         result = bus_register(&acpi_bus_type);
2066         if (result) {
2067                 /* We don't want to quit even if we failed to add suspend/resume */
2068                 printk(KERN_ERR PREFIX "Could not register bus type\n");
2069         }
2070
2071         acpi_pci_root_init();
2072         acpi_pci_link_init();
2073         acpi_processor_init();
2074         acpi_platform_init();
2075         acpi_lpss_init();
2076         acpi_cmos_rtc_init();
2077         acpi_container_init();
2078         acpi_memory_hotplug_init();
2079         acpi_dock_init();
2080
2081         mutex_lock(&acpi_scan_lock);
2082         /*
2083          * Enumerate devices in the ACPI namespace.
2084          */
2085         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2086         if (result)
2087                 goto out;
2088
2089         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2090         if (result)
2091                 goto out;
2092
2093         result = acpi_bus_scan_fixed();
2094         if (result) {
2095                 acpi_device_unregister(acpi_root);
2096                 goto out;
2097         }
2098
2099         acpi_update_all_gpes();
2100
2101         acpi_pci_root_hp_init();
2102
2103  out:
2104         mutex_unlock(&acpi_scan_lock);
2105         return result;
2106 }