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