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