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 static const char *dummy_hid = "device";
  31
  32 static LIST_HEAD(acpi_device_list);
  33 static LIST_HEAD(acpi_bus_id_list);
  34 static DEFINE_MUTEX(acpi_scan_lock);
  35 static LIST_HEAD(acpi_scan_handlers_list);
  36 DEFINE_MUTEX(acpi_device_lock);
  37 LIST_HEAD(acpi_wakeup_device_list);
  38
  39 struct acpi_device_bus_id{
  40         char bus_id[15];
  41         unsigned int instance_no;
  42         struct list_head node;
  43 };
  44
  45 void acpi_scan_lock_acquire(void)
  46 {
  47         mutex_lock(&acpi_scan_lock);
  48 }
  49 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
  50
  51 void acpi_scan_lock_release(void)
  52 {
  53         mutex_unlock(&acpi_scan_lock);
  54 }
  55 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
  56
  57 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
  58 {
  59         if (!handler || !handler->attach)
  60                 return -EINVAL;
  61
  62         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
  63         return 0;
  64 }
  65
  66 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
  67                                        const char *hotplug_profile_name)
  68 {
  69         int error;
  70
  71         error = acpi_scan_add_handler(handler);
  72         if (error)
  73                 return error;
  74
  75         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
  76         return 0;
  77 }
  78
  79 /*
  80  * Creates hid/cid(s) string needed for modalias and uevent
  81  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
  82  * char *modalias: "acpi:IBM0001:ACPI0001"
  83 */
  84 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
  85                            int size)
  86 {
  87         int len;
  88         int count;
  89         struct acpi_hardware_id *id;
  90
  91         if (list_empty(&acpi_dev->pnp.ids))
  92                 return 0;
  93
  94         len = snprintf(modalias, size, "acpi:");
  95         size -= len;
  96
  97         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
  98                 count = snprintf(&modalias[len], size, "%s:", id->id);
  99                 if (count < 0 || count >= size)
 100                         return -EINVAL;
 101                 len += count;
 102                 size -= count;
 103         }
 104
 105         modalias[len] = '\0';
 106         return len;
 107 }
 108
 109 static ssize_t
 110 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
 111         struct acpi_device *acpi_dev = to_acpi_device(dev);
 112         int len;
 113
 114         /* Device has no HID and no CID or string is >1024 */
 115         len = create_modalias(acpi_dev, buf, 1024);
 116         if (len <= 0)
 117                 return 0;
 118         buf[len++] = '\n';
 119         return len;
 120 }
 121 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
 122
 123 static int acpi_scan_hot_remove(struct acpi_device *device)
 124 {
 125         acpi_handle handle = device->handle;
 126         acpi_handle not_used;
 127         struct acpi_object_list arg_list;
 128         union acpi_object arg;
 129         acpi_status status;
 130         unsigned long long sta;
 131
 132         /* If there is no handle, the device node has been unregistered. */
 133         if (!handle) {
 134                 dev_dbg(&device->dev, "ACPI handle missing\n");
 135                 put_device(&device->dev);
 136                 return -EINVAL;
 137         }
 138
 139         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 140                 "Hot-removing device %s...\n", dev_name(&device->dev)));
 141
 142         acpi_bus_trim(device);
 143         /* Device node has been unregistered. */
 144         put_device(&device->dev);
 145         device = NULL;
 146
 147         if (ACPI_SUCCESS(acpi_get_handle(handle, "_LCK", &not_used))) {
 148                 arg_list.count = 1;
 149                 arg_list.pointer = &arg;
 150                 arg.type = ACPI_TYPE_INTEGER;
 151                 arg.integer.value = 0;
 152                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
 153         }
 154
 155         arg_list.count = 1;
 156         arg_list.pointer = &arg;
 157         arg.type = ACPI_TYPE_INTEGER;
 158         arg.integer.value = 1;
 159
 160         /*
 161          * TBD: _EJD support.
 162          */
 163         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
 164         if (ACPI_FAILURE(status)) {
 165                 if (status == AE_NOT_FOUND) {
 166                         return -ENODEV;
 167                 } else {
 168                         acpi_handle_warn(handle, "Eject failed (0x%x)\n",
 169                                                                 status);
 170                         return -EIO;
 171                 }
 172         }
 173
 174         /*
 175          * Verify if eject was indeed successful.  If not, log an error
 176          * message.  No need to call _OST since _EJ0 call was made OK.
 177          */
 178         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 179         if (ACPI_FAILURE(status)) {
 180                 acpi_handle_warn(handle,
 181                         "Status check after eject failed (0x%x)\n", status);
 182         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
 183                 acpi_handle_warn(handle,
 184                         "Eject incomplete - status 0x%llx\n", sta);
 185         }
 186
 187         return 0;
 188 }
 189
 190 static void acpi_bus_device_eject(void *context)
 191 {
 192         acpi_handle handle = context;
 193         struct acpi_device *device = NULL;
 194         struct acpi_scan_handler *handler;
 195         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 196
 197         mutex_lock(&acpi_scan_lock);
 198
 199         acpi_bus_get_device(handle, &device);
 200         if (!device)
 201                 goto err_out;
 202
 203         handler = device->handler;
 204         if (!handler || !handler->hotplug.enabled) {
 205                 ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 206                 goto err_out;
 207         }
 208         acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST,
 209                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 210         if (handler->hotplug.mode == AHM_CONTAINER) {
 211                 device->flags.eject_pending = true;
 212                 kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE);
 213         } else {
 214                 int error;
 215
 216                 get_device(&device->dev);
 217                 error = acpi_scan_hot_remove(device);
 218                 if (error)
 219                         goto err_out;
 220         }
 221
 222  out:
 223         mutex_unlock(&acpi_scan_lock);
 224         return;
 225
 226  err_out:
 227         acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST, ost_code,
 228                                   NULL);
 229         goto out;
 230 }
 231
 232 static void acpi_scan_bus_device_check(acpi_handle handle, u32 ost_source)
 233 {
 234         struct acpi_device *device = NULL;
 235         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 236         int error;
 237
 238         mutex_lock(&acpi_scan_lock);
 239
 240         if (ost_source != ACPI_NOTIFY_BUS_CHECK) {
 241                 acpi_bus_get_device(handle, &device);
 242                 if (device) {
 243                         dev_warn(&device->dev, "Attempt to re-insert\n");
 244                         goto out;
 245                 }
 246         }
 247         acpi_evaluate_hotplug_ost(handle, ost_source,
 248                                   ACPI_OST_SC_INSERT_IN_PROGRESS, NULL);
 249         error = acpi_bus_scan(handle);
 250         if (error) {
 251                 acpi_handle_warn(handle, "Namespace scan failure\n");
 252                 goto out;
 253         }
 254         error = acpi_bus_get_device(handle, &device);
 255         if (error) {
 256                 acpi_handle_warn(handle, "Missing device node object\n");
 257                 goto out;
 258         }
 259         ost_code = ACPI_OST_SC_SUCCESS;
 260         if (device->handler && device->handler->hotplug.mode == AHM_CONTAINER)
 261                 kobject_uevent(&device->dev.kobj, KOBJ_ONLINE);
 262
 263  out:
 264         acpi_evaluate_hotplug_ost(handle, ost_source, ost_code, NULL);
 265         mutex_unlock(&acpi_scan_lock);
 266 }
 267
 268 static void acpi_scan_bus_check(void *context)
 269 {
 270         acpi_scan_bus_device_check((acpi_handle)context,
 271                                    ACPI_NOTIFY_BUS_CHECK);
 272 }
 273
 274 static void acpi_scan_device_check(void *context)
 275 {
 276         acpi_scan_bus_device_check((acpi_handle)context,
 277                                    ACPI_NOTIFY_DEVICE_CHECK);
 278 }
 279
 280 static void acpi_hotplug_unsupported(acpi_handle handle, u32 type)
 281 {
 282         u32 ost_status;
 283
 284         switch (type) {
 285         case ACPI_NOTIFY_BUS_CHECK:
 286                 acpi_handle_debug(handle,
 287                         "ACPI_NOTIFY_BUS_CHECK event: unsupported\n");
 288                 ost_status = ACPI_OST_SC_INSERT_NOT_SUPPORTED;
 289                 break;
 290         case ACPI_NOTIFY_DEVICE_CHECK:
 291                 acpi_handle_debug(handle,
 292                         "ACPI_NOTIFY_DEVICE_CHECK event: unsupported\n");
 293                 ost_status = ACPI_OST_SC_INSERT_NOT_SUPPORTED;
 294                 break;
 295         case ACPI_NOTIFY_EJECT_REQUEST:
 296                 acpi_handle_debug(handle,
 297                         "ACPI_NOTIFY_EJECT_REQUEST event: unsupported\n");
 298                 ost_status = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 299                 break;
 300         default:
 301                 /* non-hotplug event; possibly handled by other handler */
 302                 return;
 303         }
 304
 305         acpi_evaluate_hotplug_ost(handle, type, ost_status, NULL);
 306 }
 307
 308 static void acpi_hotplug_notify_cb(acpi_handle handle, u32 type, void *data)
 309 {
 310         acpi_osd_exec_callback callback;
 311         struct acpi_scan_handler *handler = data;
 312         acpi_status status;
 313
 314         if (!handler->hotplug.enabled)
 315                 return acpi_hotplug_unsupported(handle, type);
 316
 317         switch (type) {
 318         case ACPI_NOTIFY_BUS_CHECK:
 319                 acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
 320                 callback = acpi_scan_bus_check;
 321                 break;
 322         case ACPI_NOTIFY_DEVICE_CHECK:
 323                 acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
 324                 callback = acpi_scan_device_check;
 325                 break;
 326         case ACPI_NOTIFY_EJECT_REQUEST:
 327                 acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
 328                 callback = acpi_bus_device_eject;
 329                 break;
 330         default:
 331                 /* non-hotplug event; possibly handled by other handler */
 332                 return;
 333         }
 334         status = acpi_os_hotplug_execute(callback, handle);
 335         if (ACPI_FAILURE(status))
 336                 acpi_evaluate_hotplug_ost(handle, type,
 337                                           ACPI_OST_SC_NON_SPECIFIC_FAILURE,
 338                                           NULL);
 339 }
 340
 341 /**
 342  * acpi_bus_hot_remove_device: hot-remove a device and its children
 343  * @context: struct acpi_eject_event pointer (freed in this func)
 344  *
 345  * Hot-remove a device and its children. This function frees up the
 346  * memory space passed by arg context, so that the caller may call
 347  * this function asynchronously through acpi_os_hotplug_execute().
 348  */
 349 void acpi_bus_hot_remove_device(void *context)
 350 {
 351         struct acpi_eject_event *ej_event = context;
 352         struct acpi_device *device = ej_event->device;
 353         acpi_handle handle = device->handle;
 354         int error;
 355
 356         mutex_lock(&acpi_scan_lock);
 357
 358         error = acpi_scan_hot_remove(device);
 359         if (error && handle)
 360                 acpi_evaluate_hotplug_ost(handle, ej_event->event,
 361                                           ACPI_OST_SC_NON_SPECIFIC_FAILURE,
 362                                           NULL);
 363
 364         mutex_unlock(&acpi_scan_lock);
 365         kfree(context);
 366 }
 367 EXPORT_SYMBOL(acpi_bus_hot_remove_device);
 368
 369 static ssize_t real_power_state_show(struct device *dev,
 370                                      struct device_attribute *attr, char *buf)
 371 {
 372         struct acpi_device *adev = to_acpi_device(dev);
 373         int state;
 374         int ret;
 375
 376         ret = acpi_device_get_power(adev, &state);
 377         if (ret)
 378                 return ret;
 379
 380         return sprintf(buf, "%s\n", acpi_power_state_string(state));
 381 }
 382
 383 static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL);
 384
 385 static ssize_t power_state_show(struct device *dev,
 386                                 struct device_attribute *attr, char *buf)
 387 {
 388         struct acpi_device *adev = to_acpi_device(dev);
 389
 390         return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
 391 }
 392
 393 static DEVICE_ATTR(power_state, 0444, power_state_show, NULL);
 394
 395 static ssize_t
 396 acpi_eject_store(struct device *d, struct device_attribute *attr,
 397                 const char *buf, size_t count)
 398 {
 399         struct acpi_device *acpi_device = to_acpi_device(d);
 400         struct acpi_eject_event *ej_event;
 401         acpi_object_type not_used;
 402         acpi_status status;
 403         u32 ost_source;
 404         int ret;
 405
 406         if (!count || buf[0] != '1')
 407                 return -EINVAL;
 408
 409         if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
 410             && !acpi_device->driver)
 411                 return -ENODEV;
 412
 413         status = acpi_get_type(acpi_device->handle, &not_used);
 414         if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
 415                 return -ENODEV;
 416
 417         mutex_lock(&acpi_scan_lock);
 418
 419         if (acpi_device->flags.eject_pending) {
 420                 /* ACPI eject notification event. */
 421                 ost_source = ACPI_NOTIFY_EJECT_REQUEST;
 422                 acpi_device->flags.eject_pending = 0;
 423         } else {
 424                 /* Eject initiated by user space. */
 425                 ost_source = ACPI_OST_EC_OSPM_EJECT;
 426         }
 427         ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
 428         if (!ej_event) {
 429                 ret = -ENOMEM;
 430                 goto err_out;
 431         }
 432         acpi_evaluate_hotplug_ost(acpi_device->handle, ost_source,
 433                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 434         ej_event->device = acpi_device;
 435         ej_event->event = ost_source;
 436         get_device(&acpi_device->dev);
 437         status = acpi_os_hotplug_execute(acpi_bus_hot_remove_device, ej_event);
 438         if (ACPI_FAILURE(status)) {
 439                 put_device(&acpi_device->dev);
 440                 kfree(ej_event);
 441                 ret = status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
 442                 goto err_out;
 443         }
 444         ret = count;
 445
 446  out:
 447         mutex_unlock(&acpi_scan_lock);
 448         return ret;
 449
 450  err_out:
 451         acpi_evaluate_hotplug_ost(acpi_device->handle, ost_source,
 452                                   ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
 453         goto out;
 454 }
 455
 456 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 457
 458 static ssize_t
 459 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 460         struct acpi_device *acpi_dev = to_acpi_device(dev);
 461
 462         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
 463 }
 464 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 465
 466 static ssize_t acpi_device_uid_show(struct device *dev,
 467                                     struct device_attribute *attr, char *buf)
 468 {
 469         struct acpi_device *acpi_dev = to_acpi_device(dev);
 470
 471         return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
 472 }
 473 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
 474
 475 static ssize_t acpi_device_adr_show(struct device *dev,
 476                                     struct device_attribute *attr, char *buf)
 477 {
 478         struct acpi_device *acpi_dev = to_acpi_device(dev);
 479
 480         return sprintf(buf, "0x%08x\n",
 481                        (unsigned int)(acpi_dev->pnp.bus_address));
 482 }
 483 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
 484
 485 static ssize_t
 486 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 487         struct acpi_device *acpi_dev = to_acpi_device(dev);
 488         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 489         int result;
 490
 491         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 492         if (result)
 493                 goto end;
 494
 495         result = sprintf(buf, "%s\n", (char*)path.pointer);
 496         kfree(path.pointer);
 497 end:
 498         return result;
 499 }
 500 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 501
 502 /* sysfs file that shows description text from the ACPI _STR method */
 503 static ssize_t description_show(struct device *dev,
 504                                 struct device_attribute *attr,
 505                                 char *buf) {
 506         struct acpi_device *acpi_dev = to_acpi_device(dev);
 507         int result;
 508
 509         if (acpi_dev->pnp.str_obj == NULL)
 510                 return 0;
 511
 512         /*
 513          * The _STR object contains a Unicode identifier for a device.
 514          * We need to convert to utf-8 so it can be displayed.
 515          */
 516         result = utf16s_to_utf8s(
 517                 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
 518                 acpi_dev->pnp.str_obj->buffer.length,
 519                 UTF16_LITTLE_ENDIAN, buf,
 520                 PAGE_SIZE);
 521
 522         buf[result++] = '\n';
 523
 524         return result;
 525 }
 526 static DEVICE_ATTR(description, 0444, description_show, NULL);
 527
 528 static ssize_t
 529 acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
 530                      char *buf) {
 531         struct acpi_device *acpi_dev = to_acpi_device(dev);
 532
 533         return sprintf(buf, "%lu\n", acpi_dev->pnp.sun);
 534 }
 535 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
 536
 537 static int acpi_device_setup_files(struct acpi_device *dev)
 538 {
 539         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 540         acpi_status status;
 541         acpi_handle temp;
 542         unsigned long long sun;
 543         int result = 0;
 544
 545         /*
 546          * Devices gotten from FADT don't have a "path" attribute
 547          */
 548         if (dev->handle) {
 549                 result = device_create_file(&dev->dev, &dev_attr_path);
 550                 if (result)
 551                         goto end;
 552         }
 553
 554         if (!list_empty(&dev->pnp.ids)) {
 555                 result = device_create_file(&dev->dev, &dev_attr_hid);
 556                 if (result)
 557                         goto end;
 558
 559                 result = device_create_file(&dev->dev, &dev_attr_modalias);
 560                 if (result)
 561                         goto end;
 562         }
 563
 564         /*
 565          * If device has _STR, 'description' file is created
 566          */
 567         status = acpi_get_handle(dev->handle, "_STR", &temp);
 568         if (ACPI_SUCCESS(status)) {
 569                 status = acpi_evaluate_object(dev->handle, "_STR",
 570                                         NULL, &buffer);
 571                 if (ACPI_FAILURE(status))
 572                         buffer.pointer = NULL;
 573                 dev->pnp.str_obj = buffer.pointer;
 574                 result = device_create_file(&dev->dev, &dev_attr_description);
 575                 if (result)
 576                         goto end;
 577         }
 578
 579         if (dev->pnp.type.bus_address)
 580                 result = device_create_file(&dev->dev, &dev_attr_adr);
 581         if (dev->pnp.unique_id)
 582                 result = device_create_file(&dev->dev, &dev_attr_uid);
 583
 584         status = acpi_evaluate_integer(dev->handle, "_SUN", NULL, &sun);
 585         if (ACPI_SUCCESS(status)) {
 586                 dev->pnp.sun = (unsigned long)sun;
 587                 result = device_create_file(&dev->dev, &dev_attr_sun);
 588                 if (result)
 589                         goto end;
 590         } else {
 591                 dev->pnp.sun = (unsigned long)-1;
 592         }
 593
 594         /*
 595          * If device has _EJ0, 'eject' file is created that is used to trigger
 596          * hot-removal function from userland.
 597          */
 598         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 599         if (ACPI_SUCCESS(status)) {
 600                 result = device_create_file(&dev->dev, &dev_attr_eject);
 601                 if (result)
 602                         return result;
 603         }
 604
 605         if (dev->flags.power_manageable) {
 606                 result = device_create_file(&dev->dev, &dev_attr_power_state);
 607                 if (result)
 608                         return result;
 609
 610                 if (dev->power.flags.power_resources)
 611                         result = device_create_file(&dev->dev,
 612                                                     &dev_attr_real_power_state);
 613         }
 614
 615 end:
 616         return result;
 617 }
 618
 619 static void acpi_device_remove_files(struct acpi_device *dev)
 620 {
 621         acpi_status status;
 622         acpi_handle temp;
 623
 624         if (dev->flags.power_manageable) {
 625                 device_remove_file(&dev->dev, &dev_attr_power_state);
 626                 if (dev->power.flags.power_resources)
 627                         device_remove_file(&dev->dev,
 628                                            &dev_attr_real_power_state);
 629         }
 630
 631         /*
 632          * If device has _STR, remove 'description' file
 633          */
 634         status = acpi_get_handle(dev->handle, "_STR", &temp);
 635         if (ACPI_SUCCESS(status)) {
 636                 kfree(dev->pnp.str_obj);
 637                 device_remove_file(&dev->dev, &dev_attr_description);
 638         }
 639         /*
 640          * If device has _EJ0, remove 'eject' file.
 641          */
 642         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 643         if (ACPI_SUCCESS(status))
 644                 device_remove_file(&dev->dev, &dev_attr_eject);
 645
 646         status = acpi_get_handle(dev->handle, "_SUN", &temp);
 647         if (ACPI_SUCCESS(status))
 648                 device_remove_file(&dev->dev, &dev_attr_sun);
 649
 650         if (dev->pnp.unique_id)
 651                 device_remove_file(&dev->dev, &dev_attr_uid);
 652         if (dev->pnp.type.bus_address)
 653                 device_remove_file(&dev->dev, &dev_attr_adr);
 654         device_remove_file(&dev->dev, &dev_attr_modalias);
 655         device_remove_file(&dev->dev, &dev_attr_hid);
 656         if (dev->handle)
 657                 device_remove_file(&dev->dev, &dev_attr_path);
 658 }
 659 /* --------------------------------------------------------------------------
 660                         ACPI Bus operations
 661    -------------------------------------------------------------------------- */
 662
 663 static const struct acpi_device_id *__acpi_match_device(
 664         struct acpi_device *device, const struct acpi_device_id *ids)
 665 {
 666         const struct acpi_device_id *id;
 667         struct acpi_hardware_id *hwid;
 668
 669         /*
 670          * If the device is not present, it is unnecessary to load device
 671          * driver for it.
 672          */
 673         if (!device->status.present)
 674                 return NULL;
 675
 676         for (id = ids; id->id[0]; id++)
 677                 list_for_each_entry(hwid, &device->pnp.ids, list)
 678                         if (!strcmp((char *) id->id, hwid->id))
 679                                 return id;
 680
 681         return NULL;
 682 }
 683
 684 /**
 685  * acpi_match_device - Match a struct device against a given list of ACPI IDs
 686  * @ids: Array of struct acpi_device_id object to match against.
 687  * @dev: The device structure to match.
 688  *
 689  * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
 690  * object for that handle and use that object to match against a given list of
 691  * device IDs.
 692  *
 693  * Return a pointer to the first matching ID on success or %NULL on failure.
 694  */
 695 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
 696                                                const struct device *dev)
 697 {
 698         struct acpi_device *adev;
 699         acpi_handle handle = ACPI_HANDLE(dev);
 700
 701         if (!ids || !handle || acpi_bus_get_device(handle, &adev))
 702                 return NULL;
 703
 704         return __acpi_match_device(adev, ids);
 705 }
 706 EXPORT_SYMBOL_GPL(acpi_match_device);
 707
 708 int acpi_match_device_ids(struct acpi_device *device,
 709                           const struct acpi_device_id *ids)
 710 {
 711         return __acpi_match_device(device, ids) ? 0 : -ENOENT;
 712 }
 713 EXPORT_SYMBOL(acpi_match_device_ids);
 714
 715 static void acpi_free_power_resources_lists(struct acpi_device *device)
 716 {
 717         int i;
 718
 719         if (device->wakeup.flags.valid)
 720                 acpi_power_resources_list_free(&device->wakeup.resources);
 721
 722         if (!device->flags.power_manageable)
 723                 return;
 724
 725         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 726                 struct acpi_device_power_state *ps = &device->power.states[i];
 727                 acpi_power_resources_list_free(&ps->resources);
 728         }
 729 }
 730
 731 static void acpi_device_release(struct device *dev)
 732 {
 733         struct acpi_device *acpi_dev = to_acpi_device(dev);
 734
 735         acpi_free_pnp_ids(&acpi_dev->pnp);
 736         acpi_free_power_resources_lists(acpi_dev);
 737         kfree(acpi_dev);
 738 }
 739
 740 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 741 {
 742         struct acpi_device *acpi_dev = to_acpi_device(dev);
 743         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 744
 745         return acpi_dev->flags.match_driver
 746                 && !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 747 }
 748
 749 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 750 {
 751         struct acpi_device *acpi_dev = to_acpi_device(dev);
 752         int len;
 753
 754         if (list_empty(&acpi_dev->pnp.ids))
 755                 return 0;
 756
 757         if (add_uevent_var(env, "MODALIAS="))
 758                 return -ENOMEM;
 759         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 760                               sizeof(env->buf) - env->buflen);
 761         if (len >= (sizeof(env->buf) - env->buflen))
 762                 return -ENOMEM;
 763         env->buflen += len;
 764         return 0;
 765 }
 766
 767 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 768 {
 769         struct acpi_device *device = data;
 770
 771         device->driver->ops.notify(device, event);
 772 }
 773
 774 static acpi_status acpi_device_notify_fixed(void *data)
 775 {
 776         struct acpi_device *device = data;
 777
 778         /* Fixed hardware devices have no handles */
 779         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 780         return AE_OK;
 781 }
 782
 783 static int acpi_device_install_notify_handler(struct acpi_device *device)
 784 {
 785         acpi_status status;
 786
 787         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 788                 status =
 789                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 790                                                      acpi_device_notify_fixed,
 791                                                      device);
 792         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 793                 status =
 794                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 795                                                      acpi_device_notify_fixed,
 796                                                      device);
 797         else
 798                 status = acpi_install_notify_handler(device->handle,
 799                                                      ACPI_DEVICE_NOTIFY,
 800                                                      acpi_device_notify,
 801                                                      device);
 802
 803         if (ACPI_FAILURE(status))
 804                 return -EINVAL;
 805         return 0;
 806 }
 807
 808 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 809 {
 810         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 811                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 812                                                 acpi_device_notify_fixed);
 813         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 814                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 815                                                 acpi_device_notify_fixed);
 816         else
 817                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 818                                            acpi_device_notify);
 819 }
 820
 821 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
 822 static int acpi_device_probe(struct device * dev)
 823 {
 824         struct acpi_device *acpi_dev = to_acpi_device(dev);
 825         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 826         int ret;
 827
 828         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
 829         if (!ret) {
 830                 if (acpi_drv->ops.notify) {
 831                         ret = acpi_device_install_notify_handler(acpi_dev);
 832                         if (ret) {
 833                                 if (acpi_drv->ops.remove)
 834                                         acpi_drv->ops.remove(acpi_dev);
 835                                 acpi_dev->driver = NULL;
 836                                 acpi_dev->driver_data = NULL;
 837                                 return ret;
 838                         }
 839                 }
 840
 841                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 842                         "Found driver [%s] for device [%s]\n",
 843                         acpi_drv->name, acpi_dev->pnp.bus_id));
 844                 get_device(dev);
 845         }
 846         return ret;
 847 }
 848
 849 static int acpi_device_remove(struct device * dev)
 850 {
 851         struct acpi_device *acpi_dev = to_acpi_device(dev);
 852         struct acpi_driver *acpi_drv = acpi_dev->driver;
 853
 854         if (acpi_drv) {
 855                 if (acpi_drv->ops.notify)
 856                         acpi_device_remove_notify_handler(acpi_dev);
 857                 if (acpi_drv->ops.remove)
 858                         acpi_drv->ops.remove(acpi_dev);
 859         }
 860         acpi_dev->driver = NULL;
 861         acpi_dev->driver_data = NULL;
 862
 863         put_device(dev);
 864         return 0;
 865 }
 866
 867 struct bus_type acpi_bus_type = {
 868         .name           = "acpi",
 869         .match          = acpi_bus_match,
 870         .probe          = acpi_device_probe,
 871         .remove         = acpi_device_remove,
 872         .uevent         = acpi_device_uevent,
 873 };
 874
 875 int acpi_device_add(struct acpi_device *device,
 876                     void (*release)(struct device *))
 877 {
 878         int result;
 879         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 880         int found = 0;
 881
 882         if (device->handle) {
 883                 acpi_status status;
 884
 885                 status = acpi_attach_data(device->handle, acpi_bus_data_handler,
 886                                           device);
 887                 if (ACPI_FAILURE(status)) {
 888                         acpi_handle_err(device->handle,
 889                                         "Unable to attach device data\n");
 890                         return -ENODEV;
 891                 }
 892         }
 893
 894         /*
 895          * Linkage
 896          * -------
 897          * Link this device to its parent and siblings.
 898          */
 899         INIT_LIST_HEAD(&device->children);
 900         INIT_LIST_HEAD(&device->node);
 901         INIT_LIST_HEAD(&device->wakeup_list);
 902         INIT_LIST_HEAD(&device->physical_node_list);
 903         mutex_init(&device->physical_node_lock);
 904         INIT_LIST_HEAD(&device->power_dependent);
 905
 906         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 907         if (!new_bus_id) {
 908                 pr_err(PREFIX "Memory allocation error\n");
 909                 result = -ENOMEM;
 910                 goto err_detach;
 911         }
 912
 913         mutex_lock(&acpi_device_lock);
 914         /*
 915          * Find suitable bus_id and instance number in acpi_bus_id_list
 916          * If failed, create one and link it into acpi_bus_id_list
 917          */
 918         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 919                 if (!strcmp(acpi_device_bus_id->bus_id,
 920                             acpi_device_hid(device))) {
 921                         acpi_device_bus_id->instance_no++;
 922                         found = 1;
 923                         kfree(new_bus_id);
 924                         break;
 925                 }
 926         }
 927         if (!found) {
 928                 acpi_device_bus_id = new_bus_id;
 929                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
 930                 acpi_device_bus_id->instance_no = 0;
 931                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 932         }
 933         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 934
 935         if (device->parent)
 936                 list_add_tail(&device->node, &device->parent->children);
 937
 938         if (device->wakeup.flags.valid)
 939                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 940         mutex_unlock(&acpi_device_lock);
 941
 942         if (device->parent)
 943                 device->dev.parent = &device->parent->dev;
 944         device->dev.bus = &acpi_bus_type;
 945         device->dev.release = release;
 946         result = device_add(&device->dev);
 947         if (result) {
 948                 dev_err(&device->dev, "Error registering device\n");
 949                 goto err;
 950         }
 951
 952         result = acpi_device_setup_files(device);
 953         if (result)
 954                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 955                        dev_name(&device->dev));
 956
 957         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
 958         return 0;
 959
 960  err:
 961         mutex_lock(&acpi_device_lock);
 962         if (device->parent)
 963                 list_del(&device->node);
 964         list_del(&device->wakeup_list);
 965         mutex_unlock(&acpi_device_lock);
 966
 967  err_detach:
 968         acpi_detach_data(device->handle, acpi_bus_data_handler);
 969         return result;
 970 }
 971
 972 static void acpi_device_unregister(struct acpi_device *device)
 973 {
 974         mutex_lock(&acpi_device_lock);
 975         if (device->parent)
 976                 list_del(&device->node);
 977
 978         list_del(&device->wakeup_list);
 979         mutex_unlock(&acpi_device_lock);
 980
 981         acpi_detach_data(device->handle, acpi_bus_data_handler);
 982
 983         acpi_power_add_remove_device(device, false);
 984         acpi_device_remove_files(device);
 985         if (device->remove)
 986                 device->remove(device);
 987
 988         device_del(&device->dev);
 989         /*
 990          * Transition the device to D3cold to drop the reference counts of all
 991          * power resources the device depends on and turn off the ones that have
 992          * no more references.
 993          */
 994         acpi_device_set_power(device, ACPI_STATE_D3_COLD);
 995         device->handle = NULL;
 996         put_device(&device->dev);
 997 }
 998
 999 /* --------------------------------------------------------------------------
1000                                  Driver Management
1001    -------------------------------------------------------------------------- */
1002 /**
1003  * acpi_bus_driver_init - add a device to a driver
1004  * @device: the device to add and initialize
1005  * @driver: driver for the device
1006  *
1007  * Used to initialize a device via its device driver.  Called whenever a
1008  * driver is bound to a device.  Invokes the driver's add() ops.
1009  */
1010 static int
1011 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
1012 {
1013         int result = 0;
1014
1015         if (!device || !driver)
1016                 return -EINVAL;
1017
1018         if (!driver->ops.add)
1019                 return -ENOSYS;
1020
1021         result = driver->ops.add(device);
1022         if (result)
1023                 return result;
1024
1025         device->driver = driver;
1026
1027         /*
1028          * TBD - Configuration Management: Assign resources to device based
1029          * upon possible configuration and currently allocated resources.
1030          */
1031
1032         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1033                           "Driver successfully bound to device\n"));
1034         return 0;
1035 }
1036
1037 /**
1038  * acpi_bus_register_driver - register a driver with the ACPI bus
1039  * @driver: driver being registered
1040  *
1041  * Registers a driver with the ACPI bus.  Searches the namespace for all
1042  * devices that match the driver's criteria and binds.  Returns zero for
1043  * success or a negative error status for failure.
1044  */
1045 int acpi_bus_register_driver(struct acpi_driver *driver)
1046 {
1047         int ret;
1048
1049         if (acpi_disabled)
1050                 return -ENODEV;
1051         driver->drv.name = driver->name;
1052         driver->drv.bus = &acpi_bus_type;
1053         driver->drv.owner = driver->owner;
1054
1055         ret = driver_register(&driver->drv);
1056         return ret;
1057 }
1058
1059 EXPORT_SYMBOL(acpi_bus_register_driver);
1060
1061 /**
1062  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
1063  * @driver: driver to unregister
1064  *
1065  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
1066  * devices that match the driver's criteria and unbinds.
1067  */
1068 void acpi_bus_unregister_driver(struct acpi_driver *driver)
1069 {
1070         driver_unregister(&driver->drv);
1071 }
1072
1073 EXPORT_SYMBOL(acpi_bus_unregister_driver);
1074
1075 /* --------------------------------------------------------------------------
1076                                  Device Enumeration
1077    -------------------------------------------------------------------------- */
1078 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
1079 {
1080         struct acpi_device *device = NULL;
1081         acpi_status status;
1082
1083         /*
1084          * Fixed hardware devices do not appear in the namespace and do not
1085          * have handles, but we fabricate acpi_devices for them, so we have
1086          * to deal with them specially.
1087          */
1088         if (!handle)
1089                 return acpi_root;
1090
1091         do {
1092                 status = acpi_get_parent(handle, &handle);
1093                 if (ACPI_FAILURE(status))
1094                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
1095         } while (acpi_bus_get_device(handle, &device));
1096         return device;
1097 }
1098
1099 acpi_status
1100 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
1101 {
1102         acpi_status status;
1103         acpi_handle tmp;
1104         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
1105         union acpi_object *obj;
1106
1107         status = acpi_get_handle(handle, "_EJD", &tmp);
1108         if (ACPI_FAILURE(status))
1109                 return status;
1110
1111         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
1112         if (ACPI_SUCCESS(status)) {
1113                 obj = buffer.pointer;
1114                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
1115                                          ejd);
1116                 kfree(buffer.pointer);
1117         }
1118         return status;
1119 }
1120 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
1121
1122 void acpi_bus_data_handler(acpi_handle handle, void *context)
1123 {
1124
1125         /* TBD */
1126
1127         return;
1128 }
1129
1130 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
1131                                         struct acpi_device_wakeup *wakeup)
1132 {
1133         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1134         union acpi_object *package = NULL;
1135         union acpi_object *element = NULL;
1136         acpi_status status;
1137         int err = -ENODATA;
1138
1139         if (!wakeup)
1140                 return -EINVAL;
1141
1142         INIT_LIST_HEAD(&wakeup->resources);
1143
1144         /* _PRW */
1145         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
1146         if (ACPI_FAILURE(status)) {
1147                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
1148                 return err;
1149         }
1150
1151         package = (union acpi_object *)buffer.pointer;
1152
1153         if (!package || package->package.count < 2)
1154                 goto out;
1155
1156         element = &(package->package.elements[0]);
1157         if (!element)
1158                 goto out;
1159
1160         if (element->type == ACPI_TYPE_PACKAGE) {
1161                 if ((element->package.count < 2) ||
1162                     (element->package.elements[0].type !=
1163                      ACPI_TYPE_LOCAL_REFERENCE)
1164                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
1165                         goto out;
1166
1167                 wakeup->gpe_device =
1168                     element->package.elements[0].reference.handle;
1169                 wakeup->gpe_number =
1170                     (u32) element->package.elements[1].integer.value;
1171         } else if (element->type == ACPI_TYPE_INTEGER) {
1172                 wakeup->gpe_device = NULL;
1173                 wakeup->gpe_number = element->integer.value;
1174         } else {
1175                 goto out;
1176         }
1177
1178         element = &(package->package.elements[1]);
1179         if (element->type != ACPI_TYPE_INTEGER)
1180                 goto out;
1181
1182         wakeup->sleep_state = element->integer.value;
1183
1184         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
1185         if (err)
1186                 goto out;
1187
1188         if (!list_empty(&wakeup->resources)) {
1189                 int sleep_state;
1190
1191                 err = acpi_power_wakeup_list_init(&wakeup->resources,
1192                                                   &sleep_state);
1193                 if (err) {
1194                         acpi_handle_warn(handle, "Retrieving current states "
1195                                          "of wakeup power resources failed\n");
1196                         acpi_power_resources_list_free(&wakeup->resources);
1197                         goto out;
1198                 }
1199                 if (sleep_state < wakeup->sleep_state) {
1200                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
1201                                          "(S%d) by S%d from power resources\n",
1202                                          (int)wakeup->sleep_state, sleep_state);
1203                         wakeup->sleep_state = sleep_state;
1204                 }
1205         }
1206         acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
1207
1208  out:
1209         kfree(buffer.pointer);
1210         return err;
1211 }
1212
1213 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
1214 {
1215         struct acpi_device_id button_device_ids[] = {
1216                 {"PNP0C0C", 0},
1217                 {"PNP0C0D", 0},
1218                 {"PNP0C0E", 0},
1219                 {"", 0},
1220         };
1221         acpi_status status;
1222         acpi_event_status event_status;
1223
1224         device->wakeup.flags.notifier_present = 0;
1225
1226         /* Power button, Lid switch always enable wakeup */
1227         if (!acpi_match_device_ids(device, button_device_ids)) {
1228                 device->wakeup.flags.run_wake = 1;
1229                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
1230                         /* Do not use Lid/sleep button for S5 wakeup */
1231                         if (device->wakeup.sleep_state == ACPI_STATE_S5)
1232                                 device->wakeup.sleep_state = ACPI_STATE_S4;
1233                 }
1234                 device_set_wakeup_capable(&device->dev, true);
1235                 return;
1236         }
1237
1238         status = acpi_get_gpe_status(device->wakeup.gpe_device,
1239                                         device->wakeup.gpe_number,
1240                                                 &event_status);
1241         if (status == AE_OK)
1242                 device->wakeup.flags.run_wake =
1243                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
1244 }
1245
1246 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1247 {
1248         acpi_handle temp;
1249         acpi_status status = 0;
1250         int err;
1251
1252         /* Presence of _PRW indicates wake capable */
1253         status = acpi_get_handle(device->handle, "_PRW", &temp);
1254         if (ACPI_FAILURE(status))
1255                 return;
1256
1257         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
1258                                                            &device->wakeup);
1259         if (err) {
1260                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
1261                 return;
1262         }
1263
1264         device->wakeup.flags.valid = 1;
1265         device->wakeup.prepare_count = 0;
1266         acpi_bus_set_run_wake_flags(device);
1267         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
1268          * system for the ACPI device with the _PRW object.
1269          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
1270          * So it is necessary to call _DSW object first. Only when it is not
1271          * present will the _PSW object used.
1272          */
1273         err = acpi_device_sleep_wake(device, 0, 0, 0);
1274         if (err)
1275                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1276                                 "error in _DSW or _PSW evaluation\n"));
1277 }
1278
1279 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1280 {
1281         struct acpi_device_power_state *ps = &device->power.states[state];
1282         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1283         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1284         acpi_handle handle;
1285         acpi_status status;
1286
1287         INIT_LIST_HEAD(&ps->resources);
1288
1289         /* Evaluate "_PRx" to get referenced power resources */
1290         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1291         if (ACPI_SUCCESS(status)) {
1292                 union acpi_object *package = buffer.pointer;
1293
1294                 if (buffer.length && package
1295                     && package->type == ACPI_TYPE_PACKAGE
1296                     && package->package.count) {
1297                         int err = acpi_extract_power_resources(package, 0,
1298                                                                &ps->resources);
1299                         if (!err)
1300                                 device->power.flags.power_resources = 1;
1301                 }
1302                 ACPI_FREE(buffer.pointer);
1303         }
1304
1305         /* Evaluate "_PSx" to see if we can do explicit sets */
1306         pathname[2] = 'S';
1307         status = acpi_get_handle(device->handle, pathname, &handle);
1308         if (ACPI_SUCCESS(status))
1309                 ps->flags.explicit_set = 1;
1310
1311         /*
1312          * State is valid if there are means to put the device into it.
1313          * D3hot is only valid if _PR3 present.
1314          */
1315         if (!list_empty(&ps->resources)
1316             || (ps->flags.explicit_set && state < ACPI_STATE_D3_HOT)) {
1317                 ps->flags.valid = 1;
1318                 ps->flags.os_accessible = 1;
1319         }
1320
1321         ps->power = -1;         /* Unknown - driver assigned */
1322         ps->latency = -1;       /* Unknown - driver assigned */
1323 }
1324
1325 static void acpi_bus_get_power_flags(struct acpi_device *device)
1326 {
1327         acpi_status status;
1328         acpi_handle handle;
1329         u32 i;
1330
1331         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1332         status = acpi_get_handle(device->handle, "_PS0", &handle);
1333         if (ACPI_FAILURE(status)) {
1334                 status = acpi_get_handle(device->handle, "_PR0", &handle);
1335                 if (ACPI_FAILURE(status))
1336                         return;
1337         }
1338
1339         device->flags.power_manageable = 1;
1340
1341         /*
1342          * Power Management Flags
1343          */
1344         status = acpi_get_handle(device->handle, "_PSC", &handle);
1345         if (ACPI_SUCCESS(status))
1346                 device->power.flags.explicit_get = 1;
1347         status = acpi_get_handle(device->handle, "_IRC", &handle);
1348         if (ACPI_SUCCESS(status))
1349                 device->power.flags.inrush_current = 1;
1350
1351         /*
1352          * Enumerate supported power management states
1353          */
1354         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1355                 acpi_bus_init_power_state(device, i);
1356
1357         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1358
1359         /* Set defaults for D0 and D3 states (always valid) */
1360         device->power.states[ACPI_STATE_D0].flags.valid = 1;
1361         device->power.states[ACPI_STATE_D0].power = 100;
1362         device->power.states[ACPI_STATE_D3].flags.valid = 1;
1363         device->power.states[ACPI_STATE_D3].power = 0;
1364
1365         /* Set D3cold's explicit_set flag if _PS3 exists. */
1366         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
1367                 device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
1368
1369         /* Presence of _PS3 or _PRx means we can put the device into D3 cold */
1370         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set ||
1371                         device->power.flags.power_resources)
1372                 device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
1373
1374         if (acpi_bus_init_power(device)) {
1375                 acpi_free_power_resources_lists(device);
1376                 device->flags.power_manageable = 0;
1377         }
1378 }
1379
1380 static void acpi_bus_get_flags(struct acpi_device *device)
1381 {
1382         acpi_status status = AE_OK;
1383         acpi_handle temp = NULL;
1384
1385         /* Presence of _STA indicates 'dynamic_status' */
1386         status = acpi_get_handle(device->handle, "_STA", &temp);
1387         if (ACPI_SUCCESS(status))
1388                 device->flags.dynamic_status = 1;
1389
1390         /* Presence of _RMV indicates 'removable' */
1391         status = acpi_get_handle(device->handle, "_RMV", &temp);
1392         if (ACPI_SUCCESS(status))
1393                 device->flags.removable = 1;
1394
1395         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1396         status = acpi_get_handle(device->handle, "_EJD", &temp);
1397         if (ACPI_SUCCESS(status))
1398                 device->flags.ejectable = 1;
1399         else {
1400                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
1401                 if (ACPI_SUCCESS(status))
1402                         device->flags.ejectable = 1;
1403         }
1404 }
1405
1406 static void acpi_device_get_busid(struct acpi_device *device)
1407 {
1408         char bus_id[5] = { '?', 0 };
1409         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1410         int i = 0;
1411
1412         /*
1413          * Bus ID
1414          * ------
1415          * The device's Bus ID is simply the object name.
1416          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1417          */
1418         if (ACPI_IS_ROOT_DEVICE(device)) {
1419                 strcpy(device->pnp.bus_id, "ACPI");
1420                 return;
1421         }
1422
1423         switch (device->device_type) {
1424         case ACPI_BUS_TYPE_POWER_BUTTON:
1425                 strcpy(device->pnp.bus_id, "PWRF");
1426                 break;
1427         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1428                 strcpy(device->pnp.bus_id, "SLPF");
1429                 break;
1430         default:
1431                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1432                 /* Clean up trailing underscores (if any) */
1433                 for (i = 3; i > 1; i--) {
1434                         if (bus_id[i] == '_')
1435                                 bus_id[i] = '\0';
1436                         else
1437                                 break;
1438                 }
1439                 strcpy(device->pnp.bus_id, bus_id);
1440                 break;
1441         }
1442 }
1443
1444 /*
1445  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1446  *
1447  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1448  * then we can safely call it an ejectable drive bay
1449  */
1450 static int acpi_bay_match(acpi_handle handle)
1451 {
1452         acpi_status status;
1453         acpi_handle tmp;
1454         acpi_handle phandle;
1455
1456         status = acpi_get_handle(handle, "_EJ0", &tmp);
1457         if (ACPI_FAILURE(status))
1458                 return -ENODEV;
1459
1460         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
1461                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
1462                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
1463                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
1464                 return 0;
1465
1466         if (acpi_get_parent(handle, &phandle))
1467                 return -ENODEV;
1468
1469         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
1470                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
1471                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
1472                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
1473                 return 0;
1474
1475         return -ENODEV;
1476 }
1477
1478 /*
1479  * acpi_dock_match - see if an acpi object has a _DCK method
1480  */
1481 static int acpi_dock_match(acpi_handle handle)
1482 {
1483         acpi_handle tmp;
1484         return acpi_get_handle(handle, "_DCK", &tmp);
1485 }
1486
1487 const char *acpi_device_hid(struct acpi_device *device)
1488 {
1489         struct acpi_hardware_id *hid;
1490
1491         if (list_empty(&device->pnp.ids))
1492                 return dummy_hid;
1493
1494         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1495         return hid->id;
1496 }
1497 EXPORT_SYMBOL(acpi_device_hid);
1498
1499 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1500 {
1501         struct acpi_hardware_id *id;
1502
1503         id = kmalloc(sizeof(*id), GFP_KERNEL);
1504         if (!id)
1505                 return;
1506
1507         id->id = kstrdup(dev_id, GFP_KERNEL);
1508         if (!id->id) {
1509                 kfree(id);
1510                 return;
1511         }
1512
1513         list_add_tail(&id->list, &pnp->ids);
1514         pnp->type.hardware_id = 1;
1515 }
1516
1517 /*
1518  * Old IBM workstations have a DSDT bug wherein the SMBus object
1519  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1520  * prefix.  Work around this.
1521  */
1522 static int acpi_ibm_smbus_match(acpi_handle handle)
1523 {
1524         acpi_handle h_dummy;
1525         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1526         int result;
1527
1528         if (!dmi_name_in_vendors("IBM"))
1529                 return -ENODEV;
1530
1531         /* Look for SMBS object */
1532         result = acpi_get_name(handle, ACPI_SINGLE_NAME, &path);
1533         if (result)
1534                 return result;
1535
1536         if (strcmp("SMBS", path.pointer)) {
1537                 result = -ENODEV;
1538                 goto out;
1539         }
1540
1541         /* Does it have the necessary (but misnamed) methods? */
1542         result = -ENODEV;
1543         if (ACPI_SUCCESS(acpi_get_handle(handle, "SBI", &h_dummy)) &&
1544             ACPI_SUCCESS(acpi_get_handle(handle, "SBR", &h_dummy)) &&
1545             ACPI_SUCCESS(acpi_get_handle(handle, "SBW", &h_dummy)))
1546                 result = 0;
1547 out:
1548         kfree(path.pointer);
1549         return result;
1550 }
1551
1552 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1553                                 int device_type)
1554 {
1555         acpi_status status;
1556         struct acpi_device_info *info;
1557         struct acpi_pnp_device_id_list *cid_list;
1558         int i;
1559
1560         switch (device_type) {
1561         case ACPI_BUS_TYPE_DEVICE:
1562                 if (handle == ACPI_ROOT_OBJECT) {
1563                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1564                         break;
1565                 }
1566
1567                 status = acpi_get_object_info(handle, &info);
1568                 if (ACPI_FAILURE(status)) {
1569                         pr_err(PREFIX "%s: Error reading device info\n",
1570                                         __func__);
1571                         return;
1572                 }
1573
1574                 if (info->valid & ACPI_VALID_HID)
1575                         acpi_add_id(pnp, info->hardware_id.string);
1576                 if (info->valid & ACPI_VALID_CID) {
1577                         cid_list = &info->compatible_id_list;
1578                         for (i = 0; i < cid_list->count; i++)
1579                                 acpi_add_id(pnp, cid_list->ids[i].string);
1580                 }
1581                 if (info->valid & ACPI_VALID_ADR) {
1582                         pnp->bus_address = info->address;
1583                         pnp->type.bus_address = 1;
1584                 }
1585                 if (info->valid & ACPI_VALID_UID)
1586                         pnp->unique_id = kstrdup(info->unique_id.string,
1587                                                         GFP_KERNEL);
1588
1589                 kfree(info);
1590
1591                 /*
1592                  * Some devices don't reliably have _HIDs & _CIDs, so add
1593                  * synthetic HIDs to make sure drivers can find them.
1594                  */
1595                 if (acpi_is_video_device(handle))
1596                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1597                 else if (ACPI_SUCCESS(acpi_bay_match(handle)))
1598                         acpi_add_id(pnp, ACPI_BAY_HID);
1599                 else if (ACPI_SUCCESS(acpi_dock_match(handle)))
1600                         acpi_add_id(pnp, ACPI_DOCK_HID);
1601                 else if (!acpi_ibm_smbus_match(handle))
1602                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1603                 else if (list_empty(&pnp->ids) && handle == ACPI_ROOT_OBJECT) {
1604                         acpi_add_id(pnp, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1605                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1606                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1607                 }
1608
1609                 break;
1610         case ACPI_BUS_TYPE_POWER:
1611                 acpi_add_id(pnp, ACPI_POWER_HID);
1612                 break;
1613         case ACPI_BUS_TYPE_PROCESSOR:
1614                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1615                 break;
1616         case ACPI_BUS_TYPE_THERMAL:
1617                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1618                 break;
1619         case ACPI_BUS_TYPE_POWER_BUTTON:
1620                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1621                 break;
1622         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1623                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1624                 break;
1625         }
1626 }
1627
1628 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1629 {
1630         struct acpi_hardware_id *id, *tmp;
1631
1632         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1633                 kfree(id->id);
1634                 kfree(id);
1635         }
1636         kfree(pnp->unique_id);
1637 }
1638
1639 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1640                              int type, unsigned long long sta)
1641 {
1642         INIT_LIST_HEAD(&device->pnp.ids);
1643         device->device_type = type;
1644         device->handle = handle;
1645         device->parent = acpi_bus_get_parent(handle);
1646         STRUCT_TO_INT(device->status) = sta;
1647         acpi_device_get_busid(device);
1648         acpi_set_pnp_ids(handle, &device->pnp, type);
1649         acpi_bus_get_flags(device);
1650         device->flags.match_driver = false;
1651         device_initialize(&device->dev);
1652         dev_set_uevent_suppress(&device->dev, true);
1653 }
1654
1655 void acpi_device_add_finalize(struct acpi_device *device)
1656 {
1657         device->flags.match_driver = true;
1658         dev_set_uevent_suppress(&device->dev, false);
1659         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1660 }
1661
1662 static int acpi_add_single_object(struct acpi_device **child,
1663                                   acpi_handle handle, int type,
1664                                   unsigned long long sta)
1665 {
1666         int result;
1667         struct acpi_device *device;
1668         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1669
1670         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1671         if (!device) {
1672                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1673                 return -ENOMEM;
1674         }
1675
1676         acpi_init_device_object(device, handle, type, sta);
1677         acpi_bus_get_power_flags(device);
1678         acpi_bus_get_wakeup_device_flags(device);
1679
1680         result = acpi_device_add(device, acpi_device_release);
1681         if (result) {
1682                 acpi_device_release(&device->dev);
1683                 return result;
1684         }
1685
1686         acpi_power_add_remove_device(device, true);
1687         acpi_device_add_finalize(device);
1688         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1689         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1690                 dev_name(&device->dev), (char *) buffer.pointer,
1691                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1692         kfree(buffer.pointer);
1693         *child = device;
1694         return 0;
1695 }
1696
1697 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1698                                     unsigned long long *sta)
1699 {
1700         acpi_status status;
1701         acpi_object_type acpi_type;
1702
1703         status = acpi_get_type(handle, &acpi_type);
1704         if (ACPI_FAILURE(status))
1705                 return -ENODEV;
1706
1707         switch (acpi_type) {
1708         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1709         case ACPI_TYPE_DEVICE:
1710                 *type = ACPI_BUS_TYPE_DEVICE;
1711                 status = acpi_bus_get_status_handle(handle, sta);
1712                 if (ACPI_FAILURE(status))
1713                         return -ENODEV;
1714                 break;
1715         case ACPI_TYPE_PROCESSOR:
1716                 *type = ACPI_BUS_TYPE_PROCESSOR;
1717                 status = acpi_bus_get_status_handle(handle, sta);
1718                 if (ACPI_FAILURE(status))
1719                         return -ENODEV;
1720                 break;
1721         case ACPI_TYPE_THERMAL:
1722                 *type = ACPI_BUS_TYPE_THERMAL;
1723                 *sta = ACPI_STA_DEFAULT;
1724                 break;
1725         case ACPI_TYPE_POWER:
1726                 *type = ACPI_BUS_TYPE_POWER;
1727                 *sta = ACPI_STA_DEFAULT;
1728                 break;
1729         default:
1730                 return -ENODEV;
1731         }
1732
1733         return 0;
1734 }
1735
1736 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1737                                        char *idstr,
1738                                        const struct acpi_device_id **matchid)
1739 {
1740         const struct acpi_device_id *devid;
1741
1742         for (devid = handler->ids; devid->id[0]; devid++)
1743                 if (!strcmp((char *)devid->id, idstr)) {
1744                         if (matchid)
1745                                 *matchid = devid;
1746
1747                         return true;
1748                 }
1749
1750         return false;
1751 }
1752
1753 static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr,
1754                                         const struct acpi_device_id **matchid)
1755 {
1756         struct acpi_scan_handler *handler;
1757
1758         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1759                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1760                         return handler;
1761
1762         return NULL;
1763 }
1764
1765 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1766 {
1767         if (!!hotplug->enabled == !!val)
1768                 return;
1769
1770         mutex_lock(&acpi_scan_lock);
1771
1772         hotplug->enabled = val;
1773
1774         mutex_unlock(&acpi_scan_lock);
1775 }
1776
1777 static void acpi_scan_init_hotplug(acpi_handle handle, int type)
1778 {
1779         struct acpi_device_pnp pnp = {};
1780         struct acpi_hardware_id *hwid;
1781         struct acpi_scan_handler *handler;
1782
1783         INIT_LIST_HEAD(&pnp.ids);
1784         acpi_set_pnp_ids(handle, &pnp, type);
1785
1786         if (!pnp.type.hardware_id)
1787                 goto out;
1788
1789         /*
1790          * This relies on the fact that acpi_install_notify_handler() will not
1791          * install the same notify handler routine twice for the same handle.
1792          */
1793         list_for_each_entry(hwid, &pnp.ids, list) {
1794                 handler = acpi_scan_match_handler(hwid->id, NULL);
1795                 if (handler) {
1796                         acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
1797                                         acpi_hotplug_notify_cb, handler);
1798                         break;
1799                 }
1800         }
1801
1802 out:
1803         acpi_free_pnp_ids(&pnp);
1804 }
1805
1806 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1807                                       void *not_used, void **return_value)
1808 {
1809         struct acpi_device *device = NULL;
1810         int type;
1811         unsigned long long sta;
1812         acpi_status status;
1813         int result;
1814
1815         acpi_bus_get_device(handle, &device);
1816         if (device)
1817                 goto out;
1818
1819         result = acpi_bus_type_and_status(handle, &type, &sta);
1820         if (result)
1821                 return AE_OK;
1822
1823         if (type == ACPI_BUS_TYPE_POWER) {
1824                 acpi_add_power_resource(handle);
1825                 return AE_OK;
1826         }
1827
1828         acpi_scan_init_hotplug(handle, type);
1829
1830         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1831             !(sta & ACPI_STA_DEVICE_FUNCTIONING)) {
1832                 struct acpi_device_wakeup wakeup;
1833                 acpi_handle temp;
1834
1835                 status = acpi_get_handle(handle, "_PRW", &temp);
1836                 if (ACPI_SUCCESS(status)) {
1837                         acpi_bus_extract_wakeup_device_power_package(handle,
1838                                                                      &wakeup);
1839                         acpi_power_resources_list_free(&wakeup.resources);
1840                 }
1841                 return AE_CTRL_DEPTH;
1842         }
1843
1844         acpi_add_single_object(&device, handle, type, sta);
1845         if (!device)
1846                 return AE_CTRL_DEPTH;
1847
1848  out:
1849         if (!*return_value)
1850                 *return_value = device;
1851
1852         return AE_OK;
1853 }
1854
1855 static int acpi_scan_attach_handler(struct acpi_device *device)
1856 {
1857         struct acpi_hardware_id *hwid;
1858         int ret = 0;
1859
1860         list_for_each_entry(hwid, &device->pnp.ids, list) {
1861                 const struct acpi_device_id *devid;
1862                 struct acpi_scan_handler *handler;
1863
1864                 handler = acpi_scan_match_handler(hwid->id, &devid);
1865                 if (handler) {
1866                         ret = handler->attach(device, devid);
1867                         if (ret > 0) {
1868                                 device->handler = handler;
1869                                 break;
1870                         } else if (ret < 0) {
1871                                 break;
1872                         }
1873                 }
1874         }
1875         return ret;
1876 }
1877
1878 static acpi_status acpi_bus_device_attach(acpi_handle handle, u32 lvl_not_used,
1879                                           void *not_used, void **ret_not_used)
1880 {
1881         struct acpi_device *device;
1882         unsigned long long sta_not_used;
1883         int ret;
1884
1885         /*
1886          * Ignore errors ignored by acpi_bus_check_add() to avoid terminating
1887          * namespace walks prematurely.
1888          */
1889         if (acpi_bus_type_and_status(handle, &ret, &sta_not_used))
1890                 return AE_OK;
1891
1892         if (acpi_bus_get_device(handle, &device))
1893                 return AE_CTRL_DEPTH;
1894
1895         if (device->handler)
1896                 return AE_OK;
1897
1898         ret = acpi_scan_attach_handler(device);
1899         if (ret)
1900                 return ret > 0 ? AE_OK : AE_CTRL_DEPTH;
1901
1902         ret = device_attach(&device->dev);
1903         return ret >= 0 ? AE_OK : AE_CTRL_DEPTH;
1904 }
1905
1906 /**
1907  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
1908  * @handle: Root of the namespace scope to scan.
1909  *
1910  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
1911  * found devices.
1912  *
1913  * If no devices were found, -ENODEV is returned, but it does not mean that
1914  * there has been a real error.  There just have been no suitable ACPI objects
1915  * in the table trunk from which the kernel could create a device and add an
1916  * appropriate driver.
1917  *
1918  * Must be called under acpi_scan_lock.
1919  */
1920 int acpi_bus_scan(acpi_handle handle)
1921 {
1922         void *device = NULL;
1923         int error = 0;
1924
1925         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
1926                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1927                                     acpi_bus_check_add, NULL, NULL, &device);
1928
1929         if (!device)
1930                 error = -ENODEV;
1931         else if (ACPI_SUCCESS(acpi_bus_device_attach(handle, 0, NULL, NULL)))
1932                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1933                                     acpi_bus_device_attach, NULL, NULL, NULL);
1934
1935         return error;
1936 }
1937 EXPORT_SYMBOL(acpi_bus_scan);
1938
1939 static acpi_status acpi_bus_device_detach(acpi_handle handle, u32 lvl_not_used,
1940                                           void *not_used, void **ret_not_used)
1941 {
1942         struct acpi_device *device = NULL;
1943
1944         if (!acpi_bus_get_device(handle, &device)) {
1945                 struct acpi_scan_handler *dev_handler = device->handler;
1946
1947                 device->removal_type = ACPI_BUS_REMOVAL_EJECT;
1948                 if (dev_handler) {
1949                         if (dev_handler->detach)
1950                                 dev_handler->detach(device);
1951
1952                         device->handler = NULL;
1953                 } else {
1954                         device_release_driver(&device->dev);
1955                 }
1956         }
1957         return AE_OK;
1958 }
1959
1960 static acpi_status acpi_bus_remove(acpi_handle handle, u32 lvl_not_used,
1961                                    void *not_used, void **ret_not_used)
1962 {
1963         struct acpi_device *device = NULL;
1964
1965         if (!acpi_bus_get_device(handle, &device))
1966                 acpi_device_unregister(device);
1967
1968         return AE_OK;
1969 }
1970
1971 /**
1972  * acpi_bus_trim - Remove ACPI device node and all of its descendants
1973  * @start: Root of the ACPI device nodes subtree to remove.
1974  *
1975  * Must be called under acpi_scan_lock.
1976  */
1977 void acpi_bus_trim(struct acpi_device *start)
1978 {
1979         /*
1980          * Execute acpi_bus_device_detach() as a post-order callback to detach
1981          * all ACPI drivers from the device nodes being removed.
1982          */
1983         acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
1984                             acpi_bus_device_detach, NULL, NULL);
1985         acpi_bus_device_detach(start->handle, 0, NULL, NULL);
1986         /*
1987          * Execute acpi_bus_remove() as a post-order callback to remove device
1988          * nodes in the given namespace scope.
1989          */
1990         acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
1991                             acpi_bus_remove, NULL, NULL);
1992         acpi_bus_remove(start->handle, 0, NULL, NULL);
1993 }
1994 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1995
1996 static int acpi_bus_scan_fixed(void)
1997 {
1998         int result = 0;
1999
2000         /*
2001          * Enumerate all fixed-feature devices.
2002          */
2003         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2004                 struct acpi_device *device = NULL;
2005
2006                 result = acpi_add_single_object(&device, NULL,
2007                                                 ACPI_BUS_TYPE_POWER_BUTTON,
2008                                                 ACPI_STA_DEFAULT);
2009                 if (result)
2010                         return result;
2011
2012                 result = device_attach(&device->dev);
2013                 if (result < 0)
2014                         return result;
2015
2016                 device_init_wakeup(&device->dev, true);
2017         }
2018
2019         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2020                 struct acpi_device *device = NULL;
2021
2022                 result = acpi_add_single_object(&device, NULL,
2023                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2024                                                 ACPI_STA_DEFAULT);
2025                 if (result)
2026                         return result;
2027
2028                 result = device_attach(&device->dev);
2029         }
2030
2031         return result < 0 ? result : 0;
2032 }
2033
2034 int __init acpi_scan_init(void)
2035 {
2036         int result;
2037
2038         result = bus_register(&acpi_bus_type);
2039         if (result) {
2040                 /* We don't want to quit even if we failed to add suspend/resume */
2041                 printk(KERN_ERR PREFIX "Could not register bus type\n");
2042         }
2043
2044         acpi_pci_root_init();
2045         acpi_pci_link_init();
2046         acpi_platform_init();
2047         acpi_lpss_init();
2048         acpi_cmos_rtc_init();
2049         acpi_container_init();
2050         acpi_memory_hotplug_init();
2051         acpi_dock_init();
2052
2053         mutex_lock(&acpi_scan_lock);
2054         /*
2055          * Enumerate devices in the ACPI namespace.
2056          */
2057         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2058         if (result)
2059                 goto out;
2060
2061         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2062         if (result)
2063                 goto out;
2064
2065         result = acpi_bus_scan_fixed();
2066         if (result) {
2067                 acpi_device_unregister(acpi_root);
2068                 goto out;
2069         }
2070
2071         acpi_update_all_gpes();
2072
2073         acpi_pci_root_hp_init();
2074
2075  out:
2076         mutex_unlock(&acpi_scan_lock);
2077         return result;
2078 }