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_bus_driver_init(struct acpi_device *, struct acpi_driver *);
 820 static int acpi_device_probe(struct device * dev)
 821 {
 822         struct acpi_device *acpi_dev = to_acpi_device(dev);
 823         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 824         int ret;
 825
 826         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
 827         if (!ret) {
 828                 if (acpi_drv->ops.notify) {
 829                         ret = acpi_device_install_notify_handler(acpi_dev);
 830                         if (ret) {
 831                                 if (acpi_drv->ops.remove)
 832                                         acpi_drv->ops.remove(acpi_dev);
 833                                 acpi_dev->driver = NULL;
 834                                 acpi_dev->driver_data = NULL;
 835                                 return ret;
 836                         }
 837                 }
 838
 839                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 840                         "Found driver [%s] for device [%s]\n",
 841                         acpi_drv->name, acpi_dev->pnp.bus_id));
 842                 get_device(dev);
 843         }
 844         return ret;
 845 }
 846
 847 static int acpi_device_remove(struct device * dev)
 848 {
 849         struct acpi_device *acpi_dev = to_acpi_device(dev);
 850         struct acpi_driver *acpi_drv = acpi_dev->driver;
 851
 852         if (acpi_drv) {
 853                 if (acpi_drv->ops.notify)
 854                         acpi_device_remove_notify_handler(acpi_dev);
 855                 if (acpi_drv->ops.remove)
 856                         acpi_drv->ops.remove(acpi_dev);
 857         }
 858         acpi_dev->driver = NULL;
 859         acpi_dev->driver_data = NULL;
 860
 861         put_device(dev);
 862         return 0;
 863 }
 864
 865 struct bus_type acpi_bus_type = {
 866         .name           = "acpi",
 867         .match          = acpi_bus_match,
 868         .probe          = acpi_device_probe,
 869         .remove         = acpi_device_remove,
 870         .uevent         = acpi_device_uevent,
 871 };
 872
 873 int acpi_device_add(struct acpi_device *device,
 874                     void (*release)(struct device *))
 875 {
 876         int result;
 877         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 878         int found = 0;
 879
 880         if (device->handle) {
 881                 acpi_status status;
 882
 883                 status = acpi_attach_data(device->handle, acpi_bus_data_handler,
 884                                           device);
 885                 if (ACPI_FAILURE(status)) {
 886                         acpi_handle_err(device->handle,
 887                                         "Unable to attach device data\n");
 888                         return -ENODEV;
 889                 }
 890         }
 891
 892         /*
 893          * Linkage
 894          * -------
 895          * Link this device to its parent and siblings.
 896          */
 897         INIT_LIST_HEAD(&device->children);
 898         INIT_LIST_HEAD(&device->node);
 899         INIT_LIST_HEAD(&device->wakeup_list);
 900         INIT_LIST_HEAD(&device->physical_node_list);
 901         mutex_init(&device->physical_node_lock);
 902         INIT_LIST_HEAD(&device->power_dependent);
 903
 904         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 905         if (!new_bus_id) {
 906                 pr_err(PREFIX "Memory allocation error\n");
 907                 result = -ENOMEM;
 908                 goto err_detach;
 909         }
 910
 911         mutex_lock(&acpi_device_lock);
 912         /*
 913          * Find suitable bus_id and instance number in acpi_bus_id_list
 914          * If failed, create one and link it into acpi_bus_id_list
 915          */
 916         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 917                 if (!strcmp(acpi_device_bus_id->bus_id,
 918                             acpi_device_hid(device))) {
 919                         acpi_device_bus_id->instance_no++;
 920                         found = 1;
 921                         kfree(new_bus_id);
 922                         break;
 923                 }
 924         }
 925         if (!found) {
 926                 acpi_device_bus_id = new_bus_id;
 927                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
 928                 acpi_device_bus_id->instance_no = 0;
 929                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 930         }
 931         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 932
 933         if (device->parent)
 934                 list_add_tail(&device->node, &device->parent->children);
 935
 936         if (device->wakeup.flags.valid)
 937                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 938         mutex_unlock(&acpi_device_lock);
 939
 940         if (device->parent)
 941                 device->dev.parent = &device->parent->dev;
 942         device->dev.bus = &acpi_bus_type;
 943         device->dev.release = release;
 944         result = device_add(&device->dev);
 945         if (result) {
 946                 dev_err(&device->dev, "Error registering device\n");
 947                 goto err;
 948         }
 949
 950         result = acpi_device_setup_files(device);
 951         if (result)
 952                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 953                        dev_name(&device->dev));
 954
 955         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
 956         return 0;
 957
 958  err:
 959         mutex_lock(&acpi_device_lock);
 960         if (device->parent)
 961                 list_del(&device->node);
 962         list_del(&device->wakeup_list);
 963         mutex_unlock(&acpi_device_lock);
 964
 965  err_detach:
 966         acpi_detach_data(device->handle, acpi_bus_data_handler);
 967         return result;
 968 }
 969
 970 static void acpi_device_unregister(struct acpi_device *device)
 971 {
 972         mutex_lock(&acpi_device_lock);
 973         if (device->parent)
 974                 list_del(&device->node);
 975
 976         list_del(&device->wakeup_list);
 977         mutex_unlock(&acpi_device_lock);
 978
 979         acpi_detach_data(device->handle, acpi_bus_data_handler);
 980
 981         acpi_power_add_remove_device(device, false);
 982         acpi_device_remove_files(device);
 983         if (device->remove)
 984                 device->remove(device);
 985
 986         device_del(&device->dev);
 987         /*
 988          * Transition the device to D3cold to drop the reference counts of all
 989          * power resources the device depends on and turn off the ones that have
 990          * no more references.
 991          */
 992         acpi_device_set_power(device, ACPI_STATE_D3_COLD);
 993         device->handle = NULL;
 994         put_device(&device->dev);
 995 }
 996
 997 /* --------------------------------------------------------------------------
 998                                  Driver Management
 999    -------------------------------------------------------------------------- */
1000 /**
1001  * acpi_bus_driver_init - add a device to a driver
1002  * @device: the device to add and initialize
1003  * @driver: driver for the device
1004  *
1005  * Used to initialize a device via its device driver.  Called whenever a
1006  * driver is bound to a device.  Invokes the driver's add() ops.
1007  */
1008 static int
1009 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
1010 {
1011         int result = 0;
1012
1013         if (!device || !driver)
1014                 return -EINVAL;
1015
1016         if (!driver->ops.add)
1017                 return -ENOSYS;
1018
1019         result = driver->ops.add(device);
1020         if (result) {
1021                 device->driver = NULL;
1022                 device->driver_data = NULL;
1023                 return result;
1024         }
1025
1026         device->driver = driver;
1027
1028         /*
1029          * TBD - Configuration Management: Assign resources to device based
1030          * upon possible configuration and currently allocated resources.
1031          */
1032
1033         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1034                           "Driver successfully bound to device\n"));
1035         return 0;
1036 }
1037
1038 /**
1039  * acpi_bus_register_driver - register a driver with the ACPI bus
1040  * @driver: driver being registered
1041  *
1042  * Registers a driver with the ACPI bus.  Searches the namespace for all
1043  * devices that match the driver's criteria and binds.  Returns zero for
1044  * success or a negative error status for failure.
1045  */
1046 int acpi_bus_register_driver(struct acpi_driver *driver)
1047 {
1048         int ret;
1049
1050         if (acpi_disabled)
1051                 return -ENODEV;
1052         driver->drv.name = driver->name;
1053         driver->drv.bus = &acpi_bus_type;
1054         driver->drv.owner = driver->owner;
1055
1056         ret = driver_register(&driver->drv);
1057         return ret;
1058 }
1059
1060 EXPORT_SYMBOL(acpi_bus_register_driver);
1061
1062 /**
1063  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
1064  * @driver: driver to unregister
1065  *
1066  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
1067  * devices that match the driver's criteria and unbinds.
1068  */
1069 void acpi_bus_unregister_driver(struct acpi_driver *driver)
1070 {
1071         driver_unregister(&driver->drv);
1072 }
1073
1074 EXPORT_SYMBOL(acpi_bus_unregister_driver);
1075
1076 /* --------------------------------------------------------------------------
1077                                  Device Enumeration
1078    -------------------------------------------------------------------------- */
1079 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
1080 {
1081         struct acpi_device *device = NULL;
1082         acpi_status status;
1083
1084         /*
1085          * Fixed hardware devices do not appear in the namespace and do not
1086          * have handles, but we fabricate acpi_devices for them, so we have
1087          * to deal with them specially.
1088          */
1089         if (!handle)
1090                 return acpi_root;
1091
1092         do {
1093                 status = acpi_get_parent(handle, &handle);
1094                 if (ACPI_FAILURE(status))
1095                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
1096         } while (acpi_bus_get_device(handle, &device));
1097         return device;
1098 }
1099
1100 acpi_status
1101 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
1102 {
1103         acpi_status status;
1104         acpi_handle tmp;
1105         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
1106         union acpi_object *obj;
1107
1108         status = acpi_get_handle(handle, "_EJD", &tmp);
1109         if (ACPI_FAILURE(status))
1110                 return status;
1111
1112         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
1113         if (ACPI_SUCCESS(status)) {
1114                 obj = buffer.pointer;
1115                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
1116                                          ejd);
1117                 kfree(buffer.pointer);
1118         }
1119         return status;
1120 }
1121 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
1122
1123 void acpi_bus_data_handler(acpi_handle handle, void *context)
1124 {
1125
1126         /* TBD */
1127
1128         return;
1129 }
1130
1131 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
1132                                         struct acpi_device_wakeup *wakeup)
1133 {
1134         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1135         union acpi_object *package = NULL;
1136         union acpi_object *element = NULL;
1137         acpi_status status;
1138         int err = -ENODATA;
1139
1140         if (!wakeup)
1141                 return -EINVAL;
1142
1143         INIT_LIST_HEAD(&wakeup->resources);
1144
1145         /* _PRW */
1146         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
1147         if (ACPI_FAILURE(status)) {
1148                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
1149                 return err;
1150         }
1151
1152         package = (union acpi_object *)buffer.pointer;
1153
1154         if (!package || package->package.count < 2)
1155                 goto out;
1156
1157         element = &(package->package.elements[0]);
1158         if (!element)
1159                 goto out;
1160
1161         if (element->type == ACPI_TYPE_PACKAGE) {
1162                 if ((element->package.count < 2) ||
1163                     (element->package.elements[0].type !=
1164                      ACPI_TYPE_LOCAL_REFERENCE)
1165                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
1166                         goto out;
1167
1168                 wakeup->gpe_device =
1169                     element->package.elements[0].reference.handle;
1170                 wakeup->gpe_number =
1171                     (u32) element->package.elements[1].integer.value;
1172         } else if (element->type == ACPI_TYPE_INTEGER) {
1173                 wakeup->gpe_device = NULL;
1174                 wakeup->gpe_number = element->integer.value;
1175         } else {
1176                 goto out;
1177         }
1178
1179         element = &(package->package.elements[1]);
1180         if (element->type != ACPI_TYPE_INTEGER)
1181                 goto out;
1182
1183         wakeup->sleep_state = element->integer.value;
1184
1185         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
1186         if (err)
1187                 goto out;
1188
1189         if (!list_empty(&wakeup->resources)) {
1190                 int sleep_state;
1191
1192                 err = acpi_power_wakeup_list_init(&wakeup->resources,
1193                                                   &sleep_state);
1194                 if (err) {
1195                         acpi_handle_warn(handle, "Retrieving current states "
1196                                          "of wakeup power resources failed\n");
1197                         acpi_power_resources_list_free(&wakeup->resources);
1198                         goto out;
1199                 }
1200                 if (sleep_state < wakeup->sleep_state) {
1201                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
1202                                          "(S%d) by S%d from power resources\n",
1203                                          (int)wakeup->sleep_state, sleep_state);
1204                         wakeup->sleep_state = sleep_state;
1205                 }
1206         }
1207         acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
1208
1209  out:
1210         kfree(buffer.pointer);
1211         return err;
1212 }
1213
1214 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
1215 {
1216         struct acpi_device_id button_device_ids[] = {
1217                 {"PNP0C0C", 0},
1218                 {"PNP0C0D", 0},
1219                 {"PNP0C0E", 0},
1220                 {"", 0},
1221         };
1222         acpi_status status;
1223         acpi_event_status event_status;
1224
1225         device->wakeup.flags.notifier_present = 0;
1226
1227         /* Power button, Lid switch always enable wakeup */
1228         if (!acpi_match_device_ids(device, button_device_ids)) {
1229                 device->wakeup.flags.run_wake = 1;
1230                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
1231                         /* Do not use Lid/sleep button for S5 wakeup */
1232                         if (device->wakeup.sleep_state == ACPI_STATE_S5)
1233                                 device->wakeup.sleep_state = ACPI_STATE_S4;
1234                 }
1235                 device_set_wakeup_capable(&device->dev, true);
1236                 return;
1237         }
1238
1239         status = acpi_get_gpe_status(device->wakeup.gpe_device,
1240                                         device->wakeup.gpe_number,
1241                                                 &event_status);
1242         if (status == AE_OK)
1243                 device->wakeup.flags.run_wake =
1244                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
1245 }
1246
1247 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1248 {
1249         acpi_handle temp;
1250         acpi_status status = 0;
1251         int err;
1252
1253         /* Presence of _PRW indicates wake capable */
1254         status = acpi_get_handle(device->handle, "_PRW", &temp);
1255         if (ACPI_FAILURE(status))
1256                 return;
1257
1258         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
1259                                                            &device->wakeup);
1260         if (err) {
1261                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
1262                 return;
1263         }
1264
1265         device->wakeup.flags.valid = 1;
1266         device->wakeup.prepare_count = 0;
1267         acpi_bus_set_run_wake_flags(device);
1268         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
1269          * system for the ACPI device with the _PRW object.
1270          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
1271          * So it is necessary to call _DSW object first. Only when it is not
1272          * present will the _PSW object used.
1273          */
1274         err = acpi_device_sleep_wake(device, 0, 0, 0);
1275         if (err)
1276                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1277                                 "error in _DSW or _PSW evaluation\n"));
1278 }
1279
1280 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1281 {
1282         struct acpi_device_power_state *ps = &device->power.states[state];
1283         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1284         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1285         acpi_handle handle;
1286         acpi_status status;
1287
1288         INIT_LIST_HEAD(&ps->resources);
1289
1290         /* Evaluate "_PRx" to get referenced power resources */
1291         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1292         if (ACPI_SUCCESS(status)) {
1293                 union acpi_object *package = buffer.pointer;
1294
1295                 if (buffer.length && package
1296                     && package->type == ACPI_TYPE_PACKAGE
1297                     && package->package.count) {
1298                         int err = acpi_extract_power_resources(package, 0,
1299                                                                &ps->resources);
1300                         if (!err)
1301                                 device->power.flags.power_resources = 1;
1302                 }
1303                 ACPI_FREE(buffer.pointer);
1304         }
1305
1306         /* Evaluate "_PSx" to see if we can do explicit sets */
1307         pathname[2] = 'S';
1308         status = acpi_get_handle(device->handle, pathname, &handle);
1309         if (ACPI_SUCCESS(status))
1310                 ps->flags.explicit_set = 1;
1311
1312         /*
1313          * State is valid if there are means to put the device into it.
1314          * D3hot is only valid if _PR3 present.
1315          */
1316         if (!list_empty(&ps->resources)
1317             || (ps->flags.explicit_set && state < ACPI_STATE_D3_HOT)) {
1318                 ps->flags.valid = 1;
1319                 ps->flags.os_accessible = 1;
1320         }
1321
1322         ps->power = -1;         /* Unknown - driver assigned */
1323         ps->latency = -1;       /* Unknown - driver assigned */
1324 }
1325
1326 static void acpi_bus_get_power_flags(struct acpi_device *device)
1327 {
1328         acpi_status status;
1329         acpi_handle handle;
1330         u32 i;
1331
1332         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1333         status = acpi_get_handle(device->handle, "_PS0", &handle);
1334         if (ACPI_FAILURE(status)) {
1335                 status = acpi_get_handle(device->handle, "_PR0", &handle);
1336                 if (ACPI_FAILURE(status))
1337                         return;
1338         }
1339
1340         device->flags.power_manageable = 1;
1341
1342         /*
1343          * Power Management Flags
1344          */
1345         status = acpi_get_handle(device->handle, "_PSC", &handle);
1346         if (ACPI_SUCCESS(status))
1347                 device->power.flags.explicit_get = 1;
1348         status = acpi_get_handle(device->handle, "_IRC", &handle);
1349         if (ACPI_SUCCESS(status))
1350                 device->power.flags.inrush_current = 1;
1351
1352         /*
1353          * Enumerate supported power management states
1354          */
1355         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1356                 acpi_bus_init_power_state(device, i);
1357
1358         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1359
1360         /* Set defaults for D0 and D3 states (always valid) */
1361         device->power.states[ACPI_STATE_D0].flags.valid = 1;
1362         device->power.states[ACPI_STATE_D0].power = 100;
1363         device->power.states[ACPI_STATE_D3].flags.valid = 1;
1364         device->power.states[ACPI_STATE_D3].power = 0;
1365
1366         /* Set D3cold's explicit_set flag if _PS3 exists. */
1367         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
1368                 device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
1369
1370         /* Presence of _PS3 or _PRx means we can put the device into D3 cold */
1371         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set ||
1372                         device->power.flags.power_resources)
1373                 device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
1374
1375         if (acpi_bus_init_power(device)) {
1376                 acpi_free_power_resources_lists(device);
1377                 device->flags.power_manageable = 0;
1378         }
1379 }
1380
1381 static void acpi_bus_get_flags(struct acpi_device *device)
1382 {
1383         acpi_status status = AE_OK;
1384         acpi_handle temp = NULL;
1385
1386         /* Presence of _STA indicates 'dynamic_status' */
1387         status = acpi_get_handle(device->handle, "_STA", &temp);
1388         if (ACPI_SUCCESS(status))
1389                 device->flags.dynamic_status = 1;
1390
1391         /* Presence of _RMV indicates 'removable' */
1392         status = acpi_get_handle(device->handle, "_RMV", &temp);
1393         if (ACPI_SUCCESS(status))
1394                 device->flags.removable = 1;
1395
1396         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1397         status = acpi_get_handle(device->handle, "_EJD", &temp);
1398         if (ACPI_SUCCESS(status))
1399                 device->flags.ejectable = 1;
1400         else {
1401                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
1402                 if (ACPI_SUCCESS(status))
1403                         device->flags.ejectable = 1;
1404         }
1405 }
1406
1407 static void acpi_device_get_busid(struct acpi_device *device)
1408 {
1409         char bus_id[5] = { '?', 0 };
1410         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1411         int i = 0;
1412
1413         /*
1414          * Bus ID
1415          * ------
1416          * The device's Bus ID is simply the object name.
1417          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1418          */
1419         if (ACPI_IS_ROOT_DEVICE(device)) {
1420                 strcpy(device->pnp.bus_id, "ACPI");
1421                 return;
1422         }
1423
1424         switch (device->device_type) {
1425         case ACPI_BUS_TYPE_POWER_BUTTON:
1426                 strcpy(device->pnp.bus_id, "PWRF");
1427                 break;
1428         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1429                 strcpy(device->pnp.bus_id, "SLPF");
1430                 break;
1431         default:
1432                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1433                 /* Clean up trailing underscores (if any) */
1434                 for (i = 3; i > 1; i--) {
1435                         if (bus_id[i] == '_')
1436                                 bus_id[i] = '\0';
1437                         else
1438                                 break;
1439                 }
1440                 strcpy(device->pnp.bus_id, bus_id);
1441                 break;
1442         }
1443 }
1444
1445 /*
1446  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1447  *
1448  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1449  * then we can safely call it an ejectable drive bay
1450  */
1451 static int acpi_bay_match(acpi_handle handle)
1452 {
1453         acpi_status status;
1454         acpi_handle tmp;
1455         acpi_handle phandle;
1456
1457         status = acpi_get_handle(handle, "_EJ0", &tmp);
1458         if (ACPI_FAILURE(status))
1459                 return -ENODEV;
1460
1461         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
1462                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
1463                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
1464                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
1465                 return 0;
1466
1467         if (acpi_get_parent(handle, &phandle))
1468                 return -ENODEV;
1469
1470         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
1471                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
1472                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
1473                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
1474                 return 0;
1475
1476         return -ENODEV;
1477 }
1478
1479 /*
1480  * acpi_dock_match - see if an acpi object has a _DCK method
1481  */
1482 static int acpi_dock_match(acpi_handle handle)
1483 {
1484         acpi_handle tmp;
1485         return acpi_get_handle(handle, "_DCK", &tmp);
1486 }
1487
1488 const char *acpi_device_hid(struct acpi_device *device)
1489 {
1490         struct acpi_hardware_id *hid;
1491
1492         if (list_empty(&device->pnp.ids))
1493                 return dummy_hid;
1494
1495         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1496         return hid->id;
1497 }
1498 EXPORT_SYMBOL(acpi_device_hid);
1499
1500 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1501 {
1502         struct acpi_hardware_id *id;
1503
1504         id = kmalloc(sizeof(*id), GFP_KERNEL);
1505         if (!id)
1506                 return;
1507
1508         id->id = kstrdup(dev_id, GFP_KERNEL);
1509         if (!id->id) {
1510                 kfree(id);
1511                 return;
1512         }
1513
1514         list_add_tail(&id->list, &pnp->ids);
1515         pnp->type.hardware_id = 1;
1516 }
1517
1518 /*
1519  * Old IBM workstations have a DSDT bug wherein the SMBus object
1520  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1521  * prefix.  Work around this.
1522  */
1523 static int acpi_ibm_smbus_match(acpi_handle handle)
1524 {
1525         acpi_handle h_dummy;
1526         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1527         int result;
1528
1529         if (!dmi_name_in_vendors("IBM"))
1530                 return -ENODEV;
1531
1532         /* Look for SMBS object */
1533         result = acpi_get_name(handle, ACPI_SINGLE_NAME, &path);
1534         if (result)
1535                 return result;
1536
1537         if (strcmp("SMBS", path.pointer)) {
1538                 result = -ENODEV;
1539                 goto out;
1540         }
1541
1542         /* Does it have the necessary (but misnamed) methods? */
1543         result = -ENODEV;
1544         if (ACPI_SUCCESS(acpi_get_handle(handle, "SBI", &h_dummy)) &&
1545             ACPI_SUCCESS(acpi_get_handle(handle, "SBR", &h_dummy)) &&
1546             ACPI_SUCCESS(acpi_get_handle(handle, "SBW", &h_dummy)))
1547                 result = 0;
1548 out:
1549         kfree(path.pointer);
1550         return result;
1551 }
1552
1553 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1554                                 int device_type)
1555 {
1556         acpi_status status;
1557         struct acpi_device_info *info;
1558         struct acpi_pnp_device_id_list *cid_list;
1559         int i;
1560
1561         switch (device_type) {
1562         case ACPI_BUS_TYPE_DEVICE:
1563                 if (handle == ACPI_ROOT_OBJECT) {
1564                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1565                         break;
1566                 }
1567
1568                 status = acpi_get_object_info(handle, &info);
1569                 if (ACPI_FAILURE(status)) {
1570                         pr_err(PREFIX "%s: Error reading device info\n",
1571                                         __func__);
1572                         return;
1573                 }
1574
1575                 if (info->valid & ACPI_VALID_HID)
1576                         acpi_add_id(pnp, info->hardware_id.string);
1577                 if (info->valid & ACPI_VALID_CID) {
1578                         cid_list = &info->compatible_id_list;
1579                         for (i = 0; i < cid_list->count; i++)
1580                                 acpi_add_id(pnp, cid_list->ids[i].string);
1581                 }
1582                 if (info->valid & ACPI_VALID_ADR) {
1583                         pnp->bus_address = info->address;
1584                         pnp->type.bus_address = 1;
1585                 }
1586                 if (info->valid & ACPI_VALID_UID)
1587                         pnp->unique_id = kstrdup(info->unique_id.string,
1588                                                         GFP_KERNEL);
1589
1590                 kfree(info);
1591
1592                 /*
1593                  * Some devices don't reliably have _HIDs & _CIDs, so add
1594                  * synthetic HIDs to make sure drivers can find them.
1595                  */
1596                 if (acpi_is_video_device(handle))
1597                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1598                 else if (ACPI_SUCCESS(acpi_bay_match(handle)))
1599                         acpi_add_id(pnp, ACPI_BAY_HID);
1600                 else if (ACPI_SUCCESS(acpi_dock_match(handle)))
1601                         acpi_add_id(pnp, ACPI_DOCK_HID);
1602                 else if (!acpi_ibm_smbus_match(handle))
1603                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1604                 else if (list_empty(&pnp->ids) && handle == ACPI_ROOT_OBJECT) {
1605                         acpi_add_id(pnp, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1606                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1607                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1608                 }
1609
1610                 break;
1611         case ACPI_BUS_TYPE_POWER:
1612                 acpi_add_id(pnp, ACPI_POWER_HID);
1613                 break;
1614         case ACPI_BUS_TYPE_PROCESSOR:
1615                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1616                 break;
1617         case ACPI_BUS_TYPE_THERMAL:
1618                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1619                 break;
1620         case ACPI_BUS_TYPE_POWER_BUTTON:
1621                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1622                 break;
1623         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1624                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1625                 break;
1626         }
1627 }
1628
1629 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1630 {
1631         struct acpi_hardware_id *id, *tmp;
1632
1633         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1634                 kfree(id->id);
1635                 kfree(id);
1636         }
1637         kfree(pnp->unique_id);
1638 }
1639
1640 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1641                              int type, unsigned long long sta)
1642 {
1643         INIT_LIST_HEAD(&device->pnp.ids);
1644         device->device_type = type;
1645         device->handle = handle;
1646         device->parent = acpi_bus_get_parent(handle);
1647         STRUCT_TO_INT(device->status) = sta;
1648         acpi_device_get_busid(device);
1649         acpi_set_pnp_ids(handle, &device->pnp, type);
1650         acpi_bus_get_flags(device);
1651         device->flags.match_driver = false;
1652         device_initialize(&device->dev);
1653         dev_set_uevent_suppress(&device->dev, true);
1654 }
1655
1656 void acpi_device_add_finalize(struct acpi_device *device)
1657 {
1658         device->flags.match_driver = true;
1659         dev_set_uevent_suppress(&device->dev, false);
1660         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1661 }
1662
1663 static int acpi_add_single_object(struct acpi_device **child,
1664                                   acpi_handle handle, int type,
1665                                   unsigned long long sta)
1666 {
1667         int result;
1668         struct acpi_device *device;
1669         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1670
1671         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1672         if (!device) {
1673                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1674                 return -ENOMEM;
1675         }
1676
1677         acpi_init_device_object(device, handle, type, sta);
1678         acpi_bus_get_power_flags(device);
1679         acpi_bus_get_wakeup_device_flags(device);
1680
1681         result = acpi_device_add(device, acpi_device_release);
1682         if (result) {
1683                 acpi_device_release(&device->dev);
1684                 return result;
1685         }
1686
1687         acpi_power_add_remove_device(device, true);
1688         acpi_device_add_finalize(device);
1689         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1690         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1691                 dev_name(&device->dev), (char *) buffer.pointer,
1692                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1693         kfree(buffer.pointer);
1694         *child = device;
1695         return 0;
1696 }
1697
1698 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1699                                     unsigned long long *sta)
1700 {
1701         acpi_status status;
1702         acpi_object_type acpi_type;
1703
1704         status = acpi_get_type(handle, &acpi_type);
1705         if (ACPI_FAILURE(status))
1706                 return -ENODEV;
1707
1708         switch (acpi_type) {
1709         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1710         case ACPI_TYPE_DEVICE:
1711                 *type = ACPI_BUS_TYPE_DEVICE;
1712                 status = acpi_bus_get_status_handle(handle, sta);
1713                 if (ACPI_FAILURE(status))
1714                         return -ENODEV;
1715                 break;
1716         case ACPI_TYPE_PROCESSOR:
1717                 *type = ACPI_BUS_TYPE_PROCESSOR;
1718                 status = acpi_bus_get_status_handle(handle, sta);
1719                 if (ACPI_FAILURE(status))
1720                         return -ENODEV;
1721                 break;
1722         case ACPI_TYPE_THERMAL:
1723                 *type = ACPI_BUS_TYPE_THERMAL;
1724                 *sta = ACPI_STA_DEFAULT;
1725                 break;
1726         case ACPI_TYPE_POWER:
1727                 *type = ACPI_BUS_TYPE_POWER;
1728                 *sta = ACPI_STA_DEFAULT;
1729                 break;
1730         default:
1731                 return -ENODEV;
1732         }
1733
1734         return 0;
1735 }
1736
1737 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1738                                        char *idstr,
1739                                        const struct acpi_device_id **matchid)
1740 {
1741         const struct acpi_device_id *devid;
1742
1743         for (devid = handler->ids; devid->id[0]; devid++)
1744                 if (!strcmp((char *)devid->id, idstr)) {
1745                         if (matchid)
1746                                 *matchid = devid;
1747
1748                         return true;
1749                 }
1750
1751         return false;
1752 }
1753
1754 static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr,
1755                                         const struct acpi_device_id **matchid)
1756 {
1757         struct acpi_scan_handler *handler;
1758
1759         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1760                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1761                         return handler;
1762
1763         return NULL;
1764 }
1765
1766 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1767 {
1768         if (!!hotplug->enabled == !!val)
1769                 return;
1770
1771         mutex_lock(&acpi_scan_lock);
1772
1773         hotplug->enabled = val;
1774
1775         mutex_unlock(&acpi_scan_lock);
1776 }
1777
1778 static void acpi_scan_init_hotplug(acpi_handle handle, int type)
1779 {
1780         struct acpi_device_pnp pnp = {};
1781         struct acpi_hardware_id *hwid;
1782         struct acpi_scan_handler *handler;
1783
1784         INIT_LIST_HEAD(&pnp.ids);
1785         acpi_set_pnp_ids(handle, &pnp, type);
1786
1787         if (!pnp.type.hardware_id)
1788                 return;
1789
1790         /*
1791          * This relies on the fact that acpi_install_notify_handler() will not
1792          * install the same notify handler routine twice for the same handle.
1793          */
1794         list_for_each_entry(hwid, &pnp.ids, list) {
1795                 handler = acpi_scan_match_handler(hwid->id, NULL);
1796                 if (handler) {
1797                         acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
1798                                         acpi_hotplug_notify_cb, handler);
1799                         break;
1800                 }
1801         }
1802
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         ret = acpi_scan_attach_handler(device);
1896         if (ret)
1897                 return ret > 0 ? AE_OK : AE_CTRL_DEPTH;
1898
1899         ret = device_attach(&device->dev);
1900         return ret >= 0 ? AE_OK : AE_CTRL_DEPTH;
1901 }
1902
1903 /**
1904  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
1905  * @handle: Root of the namespace scope to scan.
1906  *
1907  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
1908  * found devices.
1909  *
1910  * If no devices were found, -ENODEV is returned, but it does not mean that
1911  * there has been a real error.  There just have been no suitable ACPI objects
1912  * in the table trunk from which the kernel could create a device and add an
1913  * appropriate driver.
1914  *
1915  * Must be called under acpi_scan_lock.
1916  */
1917 int acpi_bus_scan(acpi_handle handle)
1918 {
1919         void *device = NULL;
1920         int error = 0;
1921
1922         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
1923                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1924                                     acpi_bus_check_add, NULL, NULL, &device);
1925
1926         if (!device)
1927                 error = -ENODEV;
1928         else if (ACPI_SUCCESS(acpi_bus_device_attach(handle, 0, NULL, NULL)))
1929                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1930                                     acpi_bus_device_attach, NULL, NULL, NULL);
1931
1932         return error;
1933 }
1934 EXPORT_SYMBOL(acpi_bus_scan);
1935
1936 static acpi_status acpi_bus_device_detach(acpi_handle handle, u32 lvl_not_used,
1937                                           void *not_used, void **ret_not_used)
1938 {
1939         struct acpi_device *device = NULL;
1940
1941         if (!acpi_bus_get_device(handle, &device)) {
1942                 struct acpi_scan_handler *dev_handler = device->handler;
1943
1944                 device->removal_type = ACPI_BUS_REMOVAL_EJECT;
1945                 if (dev_handler) {
1946                         if (dev_handler->detach)
1947                                 dev_handler->detach(device);
1948
1949                         device->handler = NULL;
1950                 } else {
1951                         device_release_driver(&device->dev);
1952                 }
1953         }
1954         return AE_OK;
1955 }
1956
1957 static acpi_status acpi_bus_remove(acpi_handle handle, u32 lvl_not_used,
1958                                    void *not_used, void **ret_not_used)
1959 {
1960         struct acpi_device *device = NULL;
1961
1962         if (!acpi_bus_get_device(handle, &device))
1963                 acpi_device_unregister(device);
1964
1965         return AE_OK;
1966 }
1967
1968 /**
1969  * acpi_bus_trim - Remove ACPI device node and all of its descendants
1970  * @start: Root of the ACPI device nodes subtree to remove.
1971  *
1972  * Must be called under acpi_scan_lock.
1973  */
1974 void acpi_bus_trim(struct acpi_device *start)
1975 {
1976         /*
1977          * Execute acpi_bus_device_detach() as a post-order callback to detach
1978          * all ACPI drivers from the device nodes being removed.
1979          */
1980         acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
1981                             acpi_bus_device_detach, NULL, NULL);
1982         acpi_bus_device_detach(start->handle, 0, NULL, NULL);
1983         /*
1984          * Execute acpi_bus_remove() as a post-order callback to remove device
1985          * nodes in the given namespace scope.
1986          */
1987         acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
1988                             acpi_bus_remove, NULL, NULL);
1989         acpi_bus_remove(start->handle, 0, NULL, NULL);
1990 }
1991 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1992
1993 static int acpi_bus_scan_fixed(void)
1994 {
1995         int result = 0;
1996
1997         /*
1998          * Enumerate all fixed-feature devices.
1999          */
2000         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2001                 struct acpi_device *device = NULL;
2002
2003                 result = acpi_add_single_object(&device, NULL,
2004                                                 ACPI_BUS_TYPE_POWER_BUTTON,
2005                                                 ACPI_STA_DEFAULT);
2006                 if (result)
2007                         return result;
2008
2009                 result = device_attach(&device->dev);
2010                 if (result < 0)
2011                         return result;
2012
2013                 device_init_wakeup(&device->dev, true);
2014         }
2015
2016         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2017                 struct acpi_device *device = NULL;
2018
2019                 result = acpi_add_single_object(&device, NULL,
2020                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2021                                                 ACPI_STA_DEFAULT);
2022                 if (result)
2023                         return result;
2024
2025                 result = device_attach(&device->dev);
2026         }
2027
2028         return result < 0 ? result : 0;
2029 }
2030
2031 int __init acpi_scan_init(void)
2032 {
2033         int result;
2034
2035         result = bus_register(&acpi_bus_type);
2036         if (result) {
2037                 /* We don't want to quit even if we failed to add suspend/resume */
2038                 printk(KERN_ERR PREFIX "Could not register bus type\n");
2039         }
2040
2041         acpi_pci_root_init();
2042         acpi_pci_link_init();
2043         acpi_platform_init();
2044         acpi_lpss_init();
2045         acpi_csrt_init();
2046         acpi_container_init();
2047         acpi_memory_hotplug_init();
2048
2049         mutex_lock(&acpi_scan_lock);
2050         /*
2051          * Enumerate devices in the ACPI namespace.
2052          */
2053         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2054         if (result)
2055                 goto out;
2056
2057         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2058         if (result)
2059                 goto out;
2060
2061         result = acpi_bus_scan_fixed();
2062         if (result) {
2063                 acpi_device_unregister(acpi_root);
2064                 goto out;
2065         }
2066
2067         acpi_update_all_gpes();
2068
2069         acpi_pci_root_hp_init();
2070
2071  out:
2072         mutex_unlock(&acpi_scan_lock);
2073         return result;
2074 }