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         /* Skip ACPI device objects with scan handlers attached. */
 744         if (acpi_dev->handler)
 745                 return 0;
 746
 747         return acpi_dev->flags.match_driver
 748                 && !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 749 }
 750
 751 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 752 {
 753         struct acpi_device *acpi_dev = to_acpi_device(dev);
 754         int len;
 755
 756         if (list_empty(&acpi_dev->pnp.ids))
 757                 return 0;
 758
 759         if (add_uevent_var(env, "MODALIAS="))
 760                 return -ENOMEM;
 761         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 762                               sizeof(env->buf) - env->buflen);
 763         if (len >= (sizeof(env->buf) - env->buflen))
 764                 return -ENOMEM;
 765         env->buflen += len;
 766         return 0;
 767 }
 768
 769 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 770 {
 771         struct acpi_device *device = data;
 772
 773         device->driver->ops.notify(device, event);
 774 }
 775
 776 static acpi_status acpi_device_notify_fixed(void *data)
 777 {
 778         struct acpi_device *device = data;
 779
 780         /* Fixed hardware devices have no handles */
 781         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 782         return AE_OK;
 783 }
 784
 785 static int acpi_device_install_notify_handler(struct acpi_device *device)
 786 {
 787         acpi_status status;
 788
 789         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 790                 status =
 791                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 792                                                      acpi_device_notify_fixed,
 793                                                      device);
 794         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 795                 status =
 796                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 797                                                      acpi_device_notify_fixed,
 798                                                      device);
 799         else
 800                 status = acpi_install_notify_handler(device->handle,
 801                                                      ACPI_DEVICE_NOTIFY,
 802                                                      acpi_device_notify,
 803                                                      device);
 804
 805         if (ACPI_FAILURE(status))
 806                 return -EINVAL;
 807         return 0;
 808 }
 809
 810 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 811 {
 812         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 813                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 814                                                 acpi_device_notify_fixed);
 815         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 816                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 817                                                 acpi_device_notify_fixed);
 818         else
 819                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 820                                            acpi_device_notify);
 821 }
 822
 823 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
 824 static int acpi_device_probe(struct device * dev)
 825 {
 826         struct acpi_device *acpi_dev = to_acpi_device(dev);
 827         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 828         int ret;
 829
 830         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
 831         if (!ret) {
 832                 if (acpi_drv->ops.notify) {
 833                         ret = acpi_device_install_notify_handler(acpi_dev);
 834                         if (ret) {
 835                                 if (acpi_drv->ops.remove)
 836                                         acpi_drv->ops.remove(acpi_dev);
 837                                 acpi_dev->driver = NULL;
 838                                 acpi_dev->driver_data = NULL;
 839                                 return ret;
 840                         }
 841                 }
 842
 843                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 844                         "Found driver [%s] for device [%s]\n",
 845                         acpi_drv->name, acpi_dev->pnp.bus_id));
 846                 get_device(dev);
 847         }
 848         return ret;
 849 }
 850
 851 static int acpi_device_remove(struct device * dev)
 852 {
 853         struct acpi_device *acpi_dev = to_acpi_device(dev);
 854         struct acpi_driver *acpi_drv = acpi_dev->driver;
 855
 856         if (acpi_drv) {
 857                 if (acpi_drv->ops.notify)
 858                         acpi_device_remove_notify_handler(acpi_dev);
 859                 if (acpi_drv->ops.remove)
 860                         acpi_drv->ops.remove(acpi_dev);
 861         }
 862         acpi_dev->driver = NULL;
 863         acpi_dev->driver_data = NULL;
 864
 865         put_device(dev);
 866         return 0;
 867 }
 868
 869 struct bus_type acpi_bus_type = {
 870         .name           = "acpi",
 871         .match          = acpi_bus_match,
 872         .probe          = acpi_device_probe,
 873         .remove         = acpi_device_remove,
 874         .uevent         = acpi_device_uevent,
 875 };
 876
 877 int acpi_device_add(struct acpi_device *device,
 878                     void (*release)(struct device *))
 879 {
 880         int result;
 881         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 882         int found = 0;
 883
 884         if (device->handle) {
 885                 acpi_status status;
 886
 887                 status = acpi_attach_data(device->handle, acpi_bus_data_handler,
 888                                           device);
 889                 if (ACPI_FAILURE(status)) {
 890                         acpi_handle_err(device->handle,
 891                                         "Unable to attach device data\n");
 892                         return -ENODEV;
 893                 }
 894         }
 895
 896         /*
 897          * Linkage
 898          * -------
 899          * Link this device to its parent and siblings.
 900          */
 901         INIT_LIST_HEAD(&device->children);
 902         INIT_LIST_HEAD(&device->node);
 903         INIT_LIST_HEAD(&device->wakeup_list);
 904         INIT_LIST_HEAD(&device->physical_node_list);
 905         mutex_init(&device->physical_node_lock);
 906         INIT_LIST_HEAD(&device->power_dependent);
 907
 908         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 909         if (!new_bus_id) {
 910                 pr_err(PREFIX "Memory allocation error\n");
 911                 result = -ENOMEM;
 912                 goto err_detach;
 913         }
 914
 915         mutex_lock(&acpi_device_lock);
 916         /*
 917          * Find suitable bus_id and instance number in acpi_bus_id_list
 918          * If failed, create one and link it into acpi_bus_id_list
 919          */
 920         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 921                 if (!strcmp(acpi_device_bus_id->bus_id,
 922                             acpi_device_hid(device))) {
 923                         acpi_device_bus_id->instance_no++;
 924                         found = 1;
 925                         kfree(new_bus_id);
 926                         break;
 927                 }
 928         }
 929         if (!found) {
 930                 acpi_device_bus_id = new_bus_id;
 931                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
 932                 acpi_device_bus_id->instance_no = 0;
 933                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 934         }
 935         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 936
 937         if (device->parent)
 938                 list_add_tail(&device->node, &device->parent->children);
 939
 940         if (device->wakeup.flags.valid)
 941                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 942         mutex_unlock(&acpi_device_lock);
 943
 944         if (device->parent)
 945                 device->dev.parent = &device->parent->dev;
 946         device->dev.bus = &acpi_bus_type;
 947         device->dev.release = release;
 948         result = device_add(&device->dev);
 949         if (result) {
 950                 dev_err(&device->dev, "Error registering device\n");
 951                 goto err;
 952         }
 953
 954         result = acpi_device_setup_files(device);
 955         if (result)
 956                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 957                        dev_name(&device->dev));
 958
 959         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
 960         return 0;
 961
 962  err:
 963         mutex_lock(&acpi_device_lock);
 964         if (device->parent)
 965                 list_del(&device->node);
 966         list_del(&device->wakeup_list);
 967         mutex_unlock(&acpi_device_lock);
 968
 969  err_detach:
 970         acpi_detach_data(device->handle, acpi_bus_data_handler);
 971         return result;
 972 }
 973
 974 static void acpi_device_unregister(struct acpi_device *device)
 975 {
 976         mutex_lock(&acpi_device_lock);
 977         if (device->parent)
 978                 list_del(&device->node);
 979
 980         list_del(&device->wakeup_list);
 981         mutex_unlock(&acpi_device_lock);
 982
 983         acpi_detach_data(device->handle, acpi_bus_data_handler);
 984
 985         acpi_power_add_remove_device(device, false);
 986         acpi_device_remove_files(device);
 987         if (device->remove)
 988                 device->remove(device);
 989
 990         device_del(&device->dev);
 991         /*
 992          * Transition the device to D3cold to drop the reference counts of all
 993          * power resources the device depends on and turn off the ones that have
 994          * no more references.
 995          */
 996         acpi_device_set_power(device, ACPI_STATE_D3_COLD);
 997         device->handle = NULL;
 998         put_device(&device->dev);
 999 }
1000
1001 /* --------------------------------------------------------------------------
1002                                  Driver Management
1003    -------------------------------------------------------------------------- */
1004 /**
1005  * acpi_bus_driver_init - add a device to a driver
1006  * @device: the device to add and initialize
1007  * @driver: driver for the device
1008  *
1009  * Used to initialize a device via its device driver.  Called whenever a
1010  * driver is bound to a device.  Invokes the driver's add() ops.
1011  */
1012 static int
1013 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
1014 {
1015         int result = 0;
1016
1017         if (!device || !driver)
1018                 return -EINVAL;
1019
1020         if (!driver->ops.add)
1021                 return -ENOSYS;
1022
1023         result = driver->ops.add(device);
1024         if (result) {
1025                 device->driver = NULL;
1026                 device->driver_data = NULL;
1027                 return result;
1028         }
1029
1030         device->driver = driver;
1031
1032         /*
1033          * TBD - Configuration Management: Assign resources to device based
1034          * upon possible configuration and currently allocated resources.
1035          */
1036
1037         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1038                           "Driver successfully bound to device\n"));
1039         return 0;
1040 }
1041
1042 /**
1043  * acpi_bus_register_driver - register a driver with the ACPI bus
1044  * @driver: driver being registered
1045  *
1046  * Registers a driver with the ACPI bus.  Searches the namespace for all
1047  * devices that match the driver's criteria and binds.  Returns zero for
1048  * success or a negative error status for failure.
1049  */
1050 int acpi_bus_register_driver(struct acpi_driver *driver)
1051 {
1052         int ret;
1053
1054         if (acpi_disabled)
1055                 return -ENODEV;
1056         driver->drv.name = driver->name;
1057         driver->drv.bus = &acpi_bus_type;
1058         driver->drv.owner = driver->owner;
1059
1060         ret = driver_register(&driver->drv);
1061         return ret;
1062 }
1063
1064 EXPORT_SYMBOL(acpi_bus_register_driver);
1065
1066 /**
1067  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
1068  * @driver: driver to unregister
1069  *
1070  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
1071  * devices that match the driver's criteria and unbinds.
1072  */
1073 void acpi_bus_unregister_driver(struct acpi_driver *driver)
1074 {
1075         driver_unregister(&driver->drv);
1076 }
1077
1078 EXPORT_SYMBOL(acpi_bus_unregister_driver);
1079
1080 /* --------------------------------------------------------------------------
1081                                  Device Enumeration
1082    -------------------------------------------------------------------------- */
1083 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
1084 {
1085         struct acpi_device *device = NULL;
1086         acpi_status status;
1087
1088         /*
1089          * Fixed hardware devices do not appear in the namespace and do not
1090          * have handles, but we fabricate acpi_devices for them, so we have
1091          * to deal with them specially.
1092          */
1093         if (!handle)
1094                 return acpi_root;
1095
1096         do {
1097                 status = acpi_get_parent(handle, &handle);
1098                 if (ACPI_FAILURE(status))
1099                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
1100         } while (acpi_bus_get_device(handle, &device));
1101         return device;
1102 }
1103
1104 acpi_status
1105 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
1106 {
1107         acpi_status status;
1108         acpi_handle tmp;
1109         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
1110         union acpi_object *obj;
1111
1112         status = acpi_get_handle(handle, "_EJD", &tmp);
1113         if (ACPI_FAILURE(status))
1114                 return status;
1115
1116         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
1117         if (ACPI_SUCCESS(status)) {
1118                 obj = buffer.pointer;
1119                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
1120                                          ejd);
1121                 kfree(buffer.pointer);
1122         }
1123         return status;
1124 }
1125 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
1126
1127 void acpi_bus_data_handler(acpi_handle handle, void *context)
1128 {
1129
1130         /* TBD */
1131
1132         return;
1133 }
1134
1135 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
1136                                         struct acpi_device_wakeup *wakeup)
1137 {
1138         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1139         union acpi_object *package = NULL;
1140         union acpi_object *element = NULL;
1141         acpi_status status;
1142         int err = -ENODATA;
1143
1144         if (!wakeup)
1145                 return -EINVAL;
1146
1147         INIT_LIST_HEAD(&wakeup->resources);
1148
1149         /* _PRW */
1150         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
1151         if (ACPI_FAILURE(status)) {
1152                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
1153                 return err;
1154         }
1155
1156         package = (union acpi_object *)buffer.pointer;
1157
1158         if (!package || package->package.count < 2)
1159                 goto out;
1160
1161         element = &(package->package.elements[0]);
1162         if (!element)
1163                 goto out;
1164
1165         if (element->type == ACPI_TYPE_PACKAGE) {
1166                 if ((element->package.count < 2) ||
1167                     (element->package.elements[0].type !=
1168                      ACPI_TYPE_LOCAL_REFERENCE)
1169                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
1170                         goto out;
1171
1172                 wakeup->gpe_device =
1173                     element->package.elements[0].reference.handle;
1174                 wakeup->gpe_number =
1175                     (u32) element->package.elements[1].integer.value;
1176         } else if (element->type == ACPI_TYPE_INTEGER) {
1177                 wakeup->gpe_device = NULL;
1178                 wakeup->gpe_number = element->integer.value;
1179         } else {
1180                 goto out;
1181         }
1182
1183         element = &(package->package.elements[1]);
1184         if (element->type != ACPI_TYPE_INTEGER)
1185                 goto out;
1186
1187         wakeup->sleep_state = element->integer.value;
1188
1189         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
1190         if (err)
1191                 goto out;
1192
1193         if (!list_empty(&wakeup->resources)) {
1194                 int sleep_state;
1195
1196                 err = acpi_power_wakeup_list_init(&wakeup->resources,
1197                                                   &sleep_state);
1198                 if (err) {
1199                         acpi_handle_warn(handle, "Retrieving current states "
1200                                          "of wakeup power resources failed\n");
1201                         acpi_power_resources_list_free(&wakeup->resources);
1202                         goto out;
1203                 }
1204                 if (sleep_state < wakeup->sleep_state) {
1205                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
1206                                          "(S%d) by S%d from power resources\n",
1207                                          (int)wakeup->sleep_state, sleep_state);
1208                         wakeup->sleep_state = sleep_state;
1209                 }
1210         }
1211         acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
1212
1213  out:
1214         kfree(buffer.pointer);
1215         return err;
1216 }
1217
1218 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
1219 {
1220         struct acpi_device_id button_device_ids[] = {
1221                 {"PNP0C0C", 0},
1222                 {"PNP0C0D", 0},
1223                 {"PNP0C0E", 0},
1224                 {"", 0},
1225         };
1226         acpi_status status;
1227         acpi_event_status event_status;
1228
1229         device->wakeup.flags.notifier_present = 0;
1230
1231         /* Power button, Lid switch always enable wakeup */
1232         if (!acpi_match_device_ids(device, button_device_ids)) {
1233                 device->wakeup.flags.run_wake = 1;
1234                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
1235                         /* Do not use Lid/sleep button for S5 wakeup */
1236                         if (device->wakeup.sleep_state == ACPI_STATE_S5)
1237                                 device->wakeup.sleep_state = ACPI_STATE_S4;
1238                 }
1239                 device_set_wakeup_capable(&device->dev, true);
1240                 return;
1241         }
1242
1243         status = acpi_get_gpe_status(device->wakeup.gpe_device,
1244                                         device->wakeup.gpe_number,
1245                                                 &event_status);
1246         if (status == AE_OK)
1247                 device->wakeup.flags.run_wake =
1248                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
1249 }
1250
1251 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1252 {
1253         acpi_handle temp;
1254         acpi_status status = 0;
1255         int err;
1256
1257         /* Presence of _PRW indicates wake capable */
1258         status = acpi_get_handle(device->handle, "_PRW", &temp);
1259         if (ACPI_FAILURE(status))
1260                 return;
1261
1262         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
1263                                                            &device->wakeup);
1264         if (err) {
1265                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
1266                 return;
1267         }
1268
1269         device->wakeup.flags.valid = 1;
1270         device->wakeup.prepare_count = 0;
1271         acpi_bus_set_run_wake_flags(device);
1272         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
1273          * system for the ACPI device with the _PRW object.
1274          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
1275          * So it is necessary to call _DSW object first. Only when it is not
1276          * present will the _PSW object used.
1277          */
1278         err = acpi_device_sleep_wake(device, 0, 0, 0);
1279         if (err)
1280                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1281                                 "error in _DSW or _PSW evaluation\n"));
1282 }
1283
1284 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1285 {
1286         struct acpi_device_power_state *ps = &device->power.states[state];
1287         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1288         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1289         acpi_handle handle;
1290         acpi_status status;
1291
1292         INIT_LIST_HEAD(&ps->resources);
1293
1294         /* Evaluate "_PRx" to get referenced power resources */
1295         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1296         if (ACPI_SUCCESS(status)) {
1297                 union acpi_object *package = buffer.pointer;
1298
1299                 if (buffer.length && package
1300                     && package->type == ACPI_TYPE_PACKAGE
1301                     && package->package.count) {
1302                         int err = acpi_extract_power_resources(package, 0,
1303                                                                &ps->resources);
1304                         if (!err)
1305                                 device->power.flags.power_resources = 1;
1306                 }
1307                 ACPI_FREE(buffer.pointer);
1308         }
1309
1310         /* Evaluate "_PSx" to see if we can do explicit sets */
1311         pathname[2] = 'S';
1312         status = acpi_get_handle(device->handle, pathname, &handle);
1313         if (ACPI_SUCCESS(status))
1314                 ps->flags.explicit_set = 1;
1315
1316         /*
1317          * State is valid if there are means to put the device into it.
1318          * D3hot is only valid if _PR3 present.
1319          */
1320         if (!list_empty(&ps->resources)
1321             || (ps->flags.explicit_set && state < ACPI_STATE_D3_HOT)) {
1322                 ps->flags.valid = 1;
1323                 ps->flags.os_accessible = 1;
1324         }
1325
1326         ps->power = -1;         /* Unknown - driver assigned */
1327         ps->latency = -1;       /* Unknown - driver assigned */
1328 }
1329
1330 static void acpi_bus_get_power_flags(struct acpi_device *device)
1331 {
1332         acpi_status status;
1333         acpi_handle handle;
1334         u32 i;
1335
1336         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1337         status = acpi_get_handle(device->handle, "_PS0", &handle);
1338         if (ACPI_FAILURE(status)) {
1339                 status = acpi_get_handle(device->handle, "_PR0", &handle);
1340                 if (ACPI_FAILURE(status))
1341                         return;
1342         }
1343
1344         device->flags.power_manageable = 1;
1345
1346         /*
1347          * Power Management Flags
1348          */
1349         status = acpi_get_handle(device->handle, "_PSC", &handle);
1350         if (ACPI_SUCCESS(status))
1351                 device->power.flags.explicit_get = 1;
1352         status = acpi_get_handle(device->handle, "_IRC", &handle);
1353         if (ACPI_SUCCESS(status))
1354                 device->power.flags.inrush_current = 1;
1355
1356         /*
1357          * Enumerate supported power management states
1358          */
1359         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1360                 acpi_bus_init_power_state(device, i);
1361
1362         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1363
1364         /* Set defaults for D0 and D3 states (always valid) */
1365         device->power.states[ACPI_STATE_D0].flags.valid = 1;
1366         device->power.states[ACPI_STATE_D0].power = 100;
1367         device->power.states[ACPI_STATE_D3].flags.valid = 1;
1368         device->power.states[ACPI_STATE_D3].power = 0;
1369
1370         /* Set D3cold's explicit_set flag if _PS3 exists. */
1371         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
1372                 device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
1373
1374         /* Presence of _PS3 or _PRx means we can put the device into D3 cold */
1375         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set ||
1376                         device->power.flags.power_resources)
1377                 device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
1378
1379         if (acpi_bus_init_power(device)) {
1380                 acpi_free_power_resources_lists(device);
1381                 device->flags.power_manageable = 0;
1382         }
1383 }
1384
1385 static void acpi_bus_get_flags(struct acpi_device *device)
1386 {
1387         acpi_status status = AE_OK;
1388         acpi_handle temp = NULL;
1389
1390         /* Presence of _STA indicates 'dynamic_status' */
1391         status = acpi_get_handle(device->handle, "_STA", &temp);
1392         if (ACPI_SUCCESS(status))
1393                 device->flags.dynamic_status = 1;
1394
1395         /* Presence of _RMV indicates 'removable' */
1396         status = acpi_get_handle(device->handle, "_RMV", &temp);
1397         if (ACPI_SUCCESS(status))
1398                 device->flags.removable = 1;
1399
1400         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1401         status = acpi_get_handle(device->handle, "_EJD", &temp);
1402         if (ACPI_SUCCESS(status))
1403                 device->flags.ejectable = 1;
1404         else {
1405                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
1406                 if (ACPI_SUCCESS(status))
1407                         device->flags.ejectable = 1;
1408         }
1409 }
1410
1411 static void acpi_device_get_busid(struct acpi_device *device)
1412 {
1413         char bus_id[5] = { '?', 0 };
1414         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1415         int i = 0;
1416
1417         /*
1418          * Bus ID
1419          * ------
1420          * The device's Bus ID is simply the object name.
1421          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1422          */
1423         if (ACPI_IS_ROOT_DEVICE(device)) {
1424                 strcpy(device->pnp.bus_id, "ACPI");
1425                 return;
1426         }
1427
1428         switch (device->device_type) {
1429         case ACPI_BUS_TYPE_POWER_BUTTON:
1430                 strcpy(device->pnp.bus_id, "PWRF");
1431                 break;
1432         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1433                 strcpy(device->pnp.bus_id, "SLPF");
1434                 break;
1435         default:
1436                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1437                 /* Clean up trailing underscores (if any) */
1438                 for (i = 3; i > 1; i--) {
1439                         if (bus_id[i] == '_')
1440                                 bus_id[i] = '\0';
1441                         else
1442                                 break;
1443                 }
1444                 strcpy(device->pnp.bus_id, bus_id);
1445                 break;
1446         }
1447 }
1448
1449 /*
1450  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1451  *
1452  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1453  * then we can safely call it an ejectable drive bay
1454  */
1455 static int acpi_bay_match(acpi_handle handle)
1456 {
1457         acpi_status status;
1458         acpi_handle tmp;
1459         acpi_handle phandle;
1460
1461         status = acpi_get_handle(handle, "_EJ0", &tmp);
1462         if (ACPI_FAILURE(status))
1463                 return -ENODEV;
1464
1465         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
1466                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
1467                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
1468                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
1469                 return 0;
1470
1471         if (acpi_get_parent(handle, &phandle))
1472                 return -ENODEV;
1473
1474         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
1475                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
1476                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
1477                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
1478                 return 0;
1479
1480         return -ENODEV;
1481 }
1482
1483 /*
1484  * acpi_dock_match - see if an acpi object has a _DCK method
1485  */
1486 static int acpi_dock_match(acpi_handle handle)
1487 {
1488         acpi_handle tmp;
1489         return acpi_get_handle(handle, "_DCK", &tmp);
1490 }
1491
1492 const char *acpi_device_hid(struct acpi_device *device)
1493 {
1494         struct acpi_hardware_id *hid;
1495
1496         if (list_empty(&device->pnp.ids))
1497                 return dummy_hid;
1498
1499         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1500         return hid->id;
1501 }
1502 EXPORT_SYMBOL(acpi_device_hid);
1503
1504 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1505 {
1506         struct acpi_hardware_id *id;
1507
1508         id = kmalloc(sizeof(*id), GFP_KERNEL);
1509         if (!id)
1510                 return;
1511
1512         id->id = kstrdup(dev_id, GFP_KERNEL);
1513         if (!id->id) {
1514                 kfree(id);
1515                 return;
1516         }
1517
1518         list_add_tail(&id->list, &pnp->ids);
1519         pnp->type.hardware_id = 1;
1520 }
1521
1522 /*
1523  * Old IBM workstations have a DSDT bug wherein the SMBus object
1524  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1525  * prefix.  Work around this.
1526  */
1527 static int acpi_ibm_smbus_match(acpi_handle handle)
1528 {
1529         acpi_handle h_dummy;
1530         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1531         int result;
1532
1533         if (!dmi_name_in_vendors("IBM"))
1534                 return -ENODEV;
1535
1536         /* Look for SMBS object */
1537         result = acpi_get_name(handle, ACPI_SINGLE_NAME, &path);
1538         if (result)
1539                 return result;
1540
1541         if (strcmp("SMBS", path.pointer)) {
1542                 result = -ENODEV;
1543                 goto out;
1544         }
1545
1546         /* Does it have the necessary (but misnamed) methods? */
1547         result = -ENODEV;
1548         if (ACPI_SUCCESS(acpi_get_handle(handle, "SBI", &h_dummy)) &&
1549             ACPI_SUCCESS(acpi_get_handle(handle, "SBR", &h_dummy)) &&
1550             ACPI_SUCCESS(acpi_get_handle(handle, "SBW", &h_dummy)))
1551                 result = 0;
1552 out:
1553         kfree(path.pointer);
1554         return result;
1555 }
1556
1557 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1558                                 int device_type)
1559 {
1560         acpi_status status;
1561         struct acpi_device_info *info;
1562         struct acpi_pnp_device_id_list *cid_list;
1563         int i;
1564
1565         switch (device_type) {
1566         case ACPI_BUS_TYPE_DEVICE:
1567                 if (handle == ACPI_ROOT_OBJECT) {
1568                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1569                         break;
1570                 }
1571
1572                 status = acpi_get_object_info(handle, &info);
1573                 if (ACPI_FAILURE(status)) {
1574                         pr_err(PREFIX "%s: Error reading device info\n",
1575                                         __func__);
1576                         return;
1577                 }
1578
1579                 if (info->valid & ACPI_VALID_HID)
1580                         acpi_add_id(pnp, info->hardware_id.string);
1581                 if (info->valid & ACPI_VALID_CID) {
1582                         cid_list = &info->compatible_id_list;
1583                         for (i = 0; i < cid_list->count; i++)
1584                                 acpi_add_id(pnp, cid_list->ids[i].string);
1585                 }
1586                 if (info->valid & ACPI_VALID_ADR) {
1587                         pnp->bus_address = info->address;
1588                         pnp->type.bus_address = 1;
1589                 }
1590                 if (info->valid & ACPI_VALID_UID)
1591                         pnp->unique_id = kstrdup(info->unique_id.string,
1592                                                         GFP_KERNEL);
1593
1594                 kfree(info);
1595
1596                 /*
1597                  * Some devices don't reliably have _HIDs & _CIDs, so add
1598                  * synthetic HIDs to make sure drivers can find them.
1599                  */
1600                 if (acpi_is_video_device(handle))
1601                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1602                 else if (ACPI_SUCCESS(acpi_bay_match(handle)))
1603                         acpi_add_id(pnp, ACPI_BAY_HID);
1604                 else if (ACPI_SUCCESS(acpi_dock_match(handle)))
1605                         acpi_add_id(pnp, ACPI_DOCK_HID);
1606                 else if (!acpi_ibm_smbus_match(handle))
1607                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1608                 else if (list_empty(&pnp->ids) && handle == ACPI_ROOT_OBJECT) {
1609                         acpi_add_id(pnp, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1610                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1611                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1612                 }
1613
1614                 break;
1615         case ACPI_BUS_TYPE_POWER:
1616                 acpi_add_id(pnp, ACPI_POWER_HID);
1617                 break;
1618         case ACPI_BUS_TYPE_PROCESSOR:
1619                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1620                 break;
1621         case ACPI_BUS_TYPE_THERMAL:
1622                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1623                 break;
1624         case ACPI_BUS_TYPE_POWER_BUTTON:
1625                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1626                 break;
1627         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1628                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1629                 break;
1630         }
1631 }
1632
1633 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1634 {
1635         struct acpi_hardware_id *id, *tmp;
1636
1637         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1638                 kfree(id->id);
1639                 kfree(id);
1640         }
1641         kfree(pnp->unique_id);
1642 }
1643
1644 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1645                              int type, unsigned long long sta)
1646 {
1647         INIT_LIST_HEAD(&device->pnp.ids);
1648         device->device_type = type;
1649         device->handle = handle;
1650         device->parent = acpi_bus_get_parent(handle);
1651         STRUCT_TO_INT(device->status) = sta;
1652         acpi_device_get_busid(device);
1653         acpi_set_pnp_ids(handle, &device->pnp, type);
1654         acpi_bus_get_flags(device);
1655         device->flags.match_driver = false;
1656         device_initialize(&device->dev);
1657         dev_set_uevent_suppress(&device->dev, true);
1658 }
1659
1660 void acpi_device_add_finalize(struct acpi_device *device)
1661 {
1662         device->flags.match_driver = true;
1663         dev_set_uevent_suppress(&device->dev, false);
1664         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1665 }
1666
1667 static int acpi_add_single_object(struct acpi_device **child,
1668                                   acpi_handle handle, int type,
1669                                   unsigned long long sta)
1670 {
1671         int result;
1672         struct acpi_device *device;
1673         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1674
1675         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1676         if (!device) {
1677                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1678                 return -ENOMEM;
1679         }
1680
1681         acpi_init_device_object(device, handle, type, sta);
1682         acpi_bus_get_power_flags(device);
1683         acpi_bus_get_wakeup_device_flags(device);
1684
1685         result = acpi_device_add(device, acpi_device_release);
1686         if (result) {
1687                 acpi_device_release(&device->dev);
1688                 return result;
1689         }
1690
1691         acpi_power_add_remove_device(device, true);
1692         acpi_device_add_finalize(device);
1693         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1694         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1695                 dev_name(&device->dev), (char *) buffer.pointer,
1696                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1697         kfree(buffer.pointer);
1698         *child = device;
1699         return 0;
1700 }
1701
1702 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1703                                     unsigned long long *sta)
1704 {
1705         acpi_status status;
1706         acpi_object_type acpi_type;
1707
1708         status = acpi_get_type(handle, &acpi_type);
1709         if (ACPI_FAILURE(status))
1710                 return -ENODEV;
1711
1712         switch (acpi_type) {
1713         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1714         case ACPI_TYPE_DEVICE:
1715                 *type = ACPI_BUS_TYPE_DEVICE;
1716                 status = acpi_bus_get_status_handle(handle, sta);
1717                 if (ACPI_FAILURE(status))
1718                         return -ENODEV;
1719                 break;
1720         case ACPI_TYPE_PROCESSOR:
1721                 *type = ACPI_BUS_TYPE_PROCESSOR;
1722                 status = acpi_bus_get_status_handle(handle, sta);
1723                 if (ACPI_FAILURE(status))
1724                         return -ENODEV;
1725                 break;
1726         case ACPI_TYPE_THERMAL:
1727                 *type = ACPI_BUS_TYPE_THERMAL;
1728                 *sta = ACPI_STA_DEFAULT;
1729                 break;
1730         case ACPI_TYPE_POWER:
1731                 *type = ACPI_BUS_TYPE_POWER;
1732                 *sta = ACPI_STA_DEFAULT;
1733                 break;
1734         default:
1735                 return -ENODEV;
1736         }
1737
1738         return 0;
1739 }
1740
1741 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1742                                        char *idstr,
1743                                        const struct acpi_device_id **matchid)
1744 {
1745         const struct acpi_device_id *devid;
1746
1747         for (devid = handler->ids; devid->id[0]; devid++)
1748                 if (!strcmp((char *)devid->id, idstr)) {
1749                         if (matchid)
1750                                 *matchid = devid;
1751
1752                         return true;
1753                 }
1754
1755         return false;
1756 }
1757
1758 static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr,
1759                                         const struct acpi_device_id **matchid)
1760 {
1761         struct acpi_scan_handler *handler;
1762
1763         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1764                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1765                         return handler;
1766
1767         return NULL;
1768 }
1769
1770 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1771 {
1772         if (!!hotplug->enabled == !!val)
1773                 return;
1774
1775         mutex_lock(&acpi_scan_lock);
1776
1777         hotplug->enabled = val;
1778
1779         mutex_unlock(&acpi_scan_lock);
1780 }
1781
1782 static void acpi_scan_init_hotplug(acpi_handle handle, int type)
1783 {
1784         struct acpi_device_pnp pnp = {};
1785         struct acpi_hardware_id *hwid;
1786         struct acpi_scan_handler *handler;
1787
1788         INIT_LIST_HEAD(&pnp.ids);
1789         acpi_set_pnp_ids(handle, &pnp, type);
1790
1791         if (!pnp.type.hardware_id)
1792                 goto out;
1793
1794         /*
1795          * This relies on the fact that acpi_install_notify_handler() will not
1796          * install the same notify handler routine twice for the same handle.
1797          */
1798         list_for_each_entry(hwid, &pnp.ids, list) {
1799                 handler = acpi_scan_match_handler(hwid->id, NULL);
1800                 if (handler) {
1801                         acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
1802                                         acpi_hotplug_notify_cb, handler);
1803                         break;
1804                 }
1805         }
1806
1807 out:
1808         acpi_free_pnp_ids(&pnp);
1809 }
1810
1811 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1812                                       void *not_used, void **return_value)
1813 {
1814         struct acpi_device *device = NULL;
1815         int type;
1816         unsigned long long sta;
1817         acpi_status status;
1818         int result;
1819
1820         acpi_bus_get_device(handle, &device);
1821         if (device)
1822                 goto out;
1823
1824         result = acpi_bus_type_and_status(handle, &type, &sta);
1825         if (result)
1826                 return AE_OK;
1827
1828         if (type == ACPI_BUS_TYPE_POWER) {
1829                 acpi_add_power_resource(handle);
1830                 return AE_OK;
1831         }
1832
1833         acpi_scan_init_hotplug(handle, type);
1834
1835         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1836             !(sta & ACPI_STA_DEVICE_FUNCTIONING)) {
1837                 struct acpi_device_wakeup wakeup;
1838                 acpi_handle temp;
1839
1840                 status = acpi_get_handle(handle, "_PRW", &temp);
1841                 if (ACPI_SUCCESS(status)) {
1842                         acpi_bus_extract_wakeup_device_power_package(handle,
1843                                                                      &wakeup);
1844                         acpi_power_resources_list_free(&wakeup.resources);
1845                 }
1846                 return AE_CTRL_DEPTH;
1847         }
1848
1849         acpi_add_single_object(&device, handle, type, sta);
1850         if (!device)
1851                 return AE_CTRL_DEPTH;
1852
1853  out:
1854         if (!*return_value)
1855                 *return_value = device;
1856
1857         return AE_OK;
1858 }
1859
1860 static int acpi_scan_attach_handler(struct acpi_device *device)
1861 {
1862         struct acpi_hardware_id *hwid;
1863         int ret = 0;
1864
1865         list_for_each_entry(hwid, &device->pnp.ids, list) {
1866                 const struct acpi_device_id *devid;
1867                 struct acpi_scan_handler *handler;
1868
1869                 handler = acpi_scan_match_handler(hwid->id, &devid);
1870                 if (handler) {
1871                         ret = handler->attach(device, devid);
1872                         if (ret > 0) {
1873                                 device->handler = handler;
1874                                 break;
1875                         } else if (ret < 0) {
1876                                 break;
1877                         }
1878                 }
1879         }
1880         return ret;
1881 }
1882
1883 static acpi_status acpi_bus_device_attach(acpi_handle handle, u32 lvl_not_used,
1884                                           void *not_used, void **ret_not_used)
1885 {
1886         struct acpi_device *device;
1887         unsigned long long sta_not_used;
1888         int ret;
1889
1890         /*
1891          * Ignore errors ignored by acpi_bus_check_add() to avoid terminating
1892          * namespace walks prematurely.
1893          */
1894         if (acpi_bus_type_and_status(handle, &ret, &sta_not_used))
1895                 return AE_OK;
1896
1897         if (acpi_bus_get_device(handle, &device))
1898                 return AE_CTRL_DEPTH;
1899
1900         ret = acpi_scan_attach_handler(device);
1901         if (ret)
1902                 return ret > 0 ? AE_OK : AE_CTRL_DEPTH;
1903
1904         ret = device_attach(&device->dev);
1905         return ret >= 0 ? AE_OK : AE_CTRL_DEPTH;
1906 }
1907
1908 /**
1909  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
1910  * @handle: Root of the namespace scope to scan.
1911  *
1912  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
1913  * found devices.
1914  *
1915  * If no devices were found, -ENODEV is returned, but it does not mean that
1916  * there has been a real error.  There just have been no suitable ACPI objects
1917  * in the table trunk from which the kernel could create a device and add an
1918  * appropriate driver.
1919  *
1920  * Must be called under acpi_scan_lock.
1921  */
1922 int acpi_bus_scan(acpi_handle handle)
1923 {
1924         void *device = NULL;
1925         int error = 0;
1926
1927         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
1928                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1929                                     acpi_bus_check_add, NULL, NULL, &device);
1930
1931         if (!device)
1932                 error = -ENODEV;
1933         else if (ACPI_SUCCESS(acpi_bus_device_attach(handle, 0, NULL, NULL)))
1934                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1935                                     acpi_bus_device_attach, NULL, NULL, NULL);
1936
1937         return error;
1938 }
1939 EXPORT_SYMBOL(acpi_bus_scan);
1940
1941 static acpi_status acpi_bus_device_detach(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                 struct acpi_scan_handler *dev_handler = device->handler;
1948
1949                 device->removal_type = ACPI_BUS_REMOVAL_EJECT;
1950                 if (dev_handler) {
1951                         if (dev_handler->detach)
1952                                 dev_handler->detach(device);
1953
1954                         device->handler = NULL;
1955                 } else {
1956                         device_release_driver(&device->dev);
1957                 }
1958         }
1959         return AE_OK;
1960 }
1961
1962 static acpi_status acpi_bus_remove(acpi_handle handle, u32 lvl_not_used,
1963                                    void *not_used, void **ret_not_used)
1964 {
1965         struct acpi_device *device = NULL;
1966
1967         if (!acpi_bus_get_device(handle, &device))
1968                 acpi_device_unregister(device);
1969
1970         return AE_OK;
1971 }
1972
1973 /**
1974  * acpi_bus_trim - Remove ACPI device node and all of its descendants
1975  * @start: Root of the ACPI device nodes subtree to remove.
1976  *
1977  * Must be called under acpi_scan_lock.
1978  */
1979 void acpi_bus_trim(struct acpi_device *start)
1980 {
1981         /*
1982          * Execute acpi_bus_device_detach() as a post-order callback to detach
1983          * all ACPI drivers from the device nodes being removed.
1984          */
1985         acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
1986                             acpi_bus_device_detach, NULL, NULL);
1987         acpi_bus_device_detach(start->handle, 0, NULL, NULL);
1988         /*
1989          * Execute acpi_bus_remove() as a post-order callback to remove device
1990          * nodes in the given namespace scope.
1991          */
1992         acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
1993                             acpi_bus_remove, NULL, NULL);
1994         acpi_bus_remove(start->handle, 0, NULL, NULL);
1995 }
1996 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1997
1998 static int acpi_bus_scan_fixed(void)
1999 {
2000         int result = 0;
2001
2002         /*
2003          * Enumerate all fixed-feature devices.
2004          */
2005         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2006                 struct acpi_device *device = NULL;
2007
2008                 result = acpi_add_single_object(&device, NULL,
2009                                                 ACPI_BUS_TYPE_POWER_BUTTON,
2010                                                 ACPI_STA_DEFAULT);
2011                 if (result)
2012                         return result;
2013
2014                 result = device_attach(&device->dev);
2015                 if (result < 0)
2016                         return result;
2017
2018                 device_init_wakeup(&device->dev, true);
2019         }
2020
2021         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2022                 struct acpi_device *device = NULL;
2023
2024                 result = acpi_add_single_object(&device, NULL,
2025                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2026                                                 ACPI_STA_DEFAULT);
2027                 if (result)
2028                         return result;
2029
2030                 result = device_attach(&device->dev);
2031         }
2032
2033         return result < 0 ? result : 0;
2034 }
2035
2036 int __init acpi_scan_init(void)
2037 {
2038         int result;
2039
2040         result = bus_register(&acpi_bus_type);
2041         if (result) {
2042                 /* We don't want to quit even if we failed to add suspend/resume */
2043                 printk(KERN_ERR PREFIX "Could not register bus type\n");
2044         }
2045
2046         acpi_pci_root_init();
2047         acpi_pci_link_init();
2048         acpi_platform_init();
2049         acpi_lpss_init();
2050         acpi_container_init();
2051         acpi_memory_hotplug_init();
2052
2053         mutex_lock(&acpi_scan_lock);
2054         /*
2055          * Enumerate devices in the ACPI namespace.
2056          */
2057         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2058         if (result)
2059                 goto out;
2060
2061         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2062         if (result)
2063                 goto out;
2064
2065         result = acpi_bus_scan_fixed();
2066         if (result) {
2067                 acpi_device_unregister(acpi_root);
2068                 goto out;
2069         }
2070
2071         acpi_update_all_gpes();
2072
2073         acpi_pci_root_hp_init();
2074
2075  out:
2076         mutex_unlock(&acpi_scan_lock);
2077         return result;
2078 }