Pileus Git - ~andy/linux/blob - 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 <asm/pgtable.h>
  16
  17 #include "internal.h"
  18
  19 #define _COMPONENT              ACPI_BUS_COMPONENT
  20 ACPI_MODULE_NAME("scan");
  21 extern struct acpi_device *acpi_root;
  22
  23 #define ACPI_BUS_CLASS                  "system_bus"
  24 #define ACPI_BUS_HID                    "LNXSYBUS"
  25 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  26
  27 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
  28
  29 #define INVALID_ACPI_HANDLE     ((acpi_handle)empty_zero_page)
  30
  31 /*
  32  * If set, devices will be hot-removed even if they cannot be put offline
  33  * gracefully (from the kernel's standpoint).
  34  */
  35 bool acpi_force_hot_remove;
  36
  37 static const char *dummy_hid = "device";
  38
  39 static LIST_HEAD(acpi_bus_id_list);
  40 static DEFINE_MUTEX(acpi_scan_lock);
  41 static LIST_HEAD(acpi_scan_handlers_list);
  42 DEFINE_MUTEX(acpi_device_lock);
  43 LIST_HEAD(acpi_wakeup_device_list);
  44
  45 struct acpi_device_bus_id{
  46         char bus_id[15];
  47         unsigned int instance_no;
  48         struct list_head node;
  49 };
  50
  51 void acpi_scan_lock_acquire(void)
  52 {
  53         mutex_lock(&acpi_scan_lock);
  54 }
  55 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
  56
  57 void acpi_scan_lock_release(void)
  58 {
  59         mutex_unlock(&acpi_scan_lock);
  60 }
  61 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
  62
  63 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
  64 {
  65         if (!handler || !handler->attach)
  66                 return -EINVAL;
  67
  68         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
  69         return 0;
  70 }
  71
  72 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
  73                                        const char *hotplug_profile_name)
  74 {
  75         int error;
  76
  77         error = acpi_scan_add_handler(handler);
  78         if (error)
  79                 return error;
  80
  81         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
  82         return 0;
  83 }
  84
  85 /*
  86  * Creates hid/cid(s) string needed for modalias and uevent
  87  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
  88  * char *modalias: "acpi:IBM0001:ACPI0001"
  89 */
  90 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
  91                            int size)
  92 {
  93         int len;
  94         int count;
  95         struct acpi_hardware_id *id;
  96
  97         if (list_empty(&acpi_dev->pnp.ids))
  98                 return 0;
  99
 100         len = snprintf(modalias, size, "acpi:");
 101         size -= len;
 102
 103         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
 104                 count = snprintf(&modalias[len], size, "%s:", id->id);
 105                 if (count < 0 || count >= size)
 106                         return -EINVAL;
 107                 len += count;
 108                 size -= count;
 109         }
 110
 111         modalias[len] = '\0';
 112         return len;
 113 }
 114
 115 static ssize_t
 116 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
 117         struct acpi_device *acpi_dev = to_acpi_device(dev);
 118         int len;
 119
 120         /* Device has no HID and no CID or string is >1024 */
 121         len = create_modalias(acpi_dev, buf, 1024);
 122         if (len <= 0)
 123                 return 0;
 124         buf[len++] = '\n';
 125         return len;
 126 }
 127 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
 128
 129 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
 130 {
 131         struct acpi_device_physical_node *pn;
 132         bool offline = true;
 133
 134         mutex_lock(&adev->physical_node_lock);
 135
 136         list_for_each_entry(pn, &adev->physical_node_list, node)
 137                 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
 138                         if (uevent)
 139                                 kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
 140
 141                         offline = false;
 142                         break;
 143                 }
 144
 145         mutex_unlock(&adev->physical_node_lock);
 146         return offline;
 147 }
 148
 149 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
 150                                     void **ret_p)
 151 {
 152         struct acpi_device *device = NULL;
 153         struct acpi_device_physical_node *pn;
 154         bool second_pass = (bool)data;
 155         acpi_status status = AE_OK;
 156
 157         if (acpi_bus_get_device(handle, &device))
 158                 return AE_OK;
 159
 160         if (device->handler && !device->handler->hotplug.enabled) {
 161                 *ret_p = &device->dev;
 162                 return AE_SUPPORT;
 163         }
 164
 165         mutex_lock(&device->physical_node_lock);
 166
 167         list_for_each_entry(pn, &device->physical_node_list, node) {
 168                 int ret;
 169
 170                 if (second_pass) {
 171                         /* Skip devices offlined by the first pass. */
 172                         if (pn->put_online)
 173                                 continue;
 174                 } else {
 175                         pn->put_online = false;
 176                 }
 177                 ret = device_offline(pn->dev);
 178                 if (acpi_force_hot_remove)
 179                         continue;
 180
 181                 if (ret >= 0) {
 182                         pn->put_online = !ret;
 183                 } else {
 184                         *ret_p = pn->dev;
 185                         if (second_pass) {
 186                                 status = AE_ERROR;
 187                                 break;
 188                         }
 189                 }
 190         }
 191
 192         mutex_unlock(&device->physical_node_lock);
 193
 194         return status;
 195 }
 196
 197 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
 198                                    void **ret_p)
 199 {
 200         struct acpi_device *device = NULL;
 201         struct acpi_device_physical_node *pn;
 202
 203         if (acpi_bus_get_device(handle, &device))
 204                 return AE_OK;
 205
 206         mutex_lock(&device->physical_node_lock);
 207
 208         list_for_each_entry(pn, &device->physical_node_list, node)
 209                 if (pn->put_online) {
 210                         device_online(pn->dev);
 211                         pn->put_online = false;
 212                 }
 213
 214         mutex_unlock(&device->physical_node_lock);
 215
 216         return AE_OK;
 217 }
 218
 219 static int acpi_scan_try_to_offline(struct acpi_device *device)
 220 {
 221         acpi_handle handle = device->handle;
 222         struct device *errdev = NULL;
 223         acpi_status status;
 224
 225         /*
 226          * Carry out two passes here and ignore errors in the first pass,
 227          * because if the devices in question are memory blocks and
 228          * CONFIG_MEMCG is set, one of the blocks may hold data structures
 229          * that the other blocks depend on, but it is not known in advance which
 230          * block holds them.
 231          *
 232          * If the first pass is successful, the second one isn't needed, though.
 233          */
 234         status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 235                                      NULL, acpi_bus_offline, (void *)false,
 236                                      (void **)&errdev);
 237         if (status == AE_SUPPORT) {
 238                 dev_warn(errdev, "Offline disabled.\n");
 239                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 240                                     acpi_bus_online, NULL, NULL, NULL);
 241                 return -EPERM;
 242         }
 243         acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
 244         if (errdev) {
 245                 errdev = NULL;
 246                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 247                                     NULL, acpi_bus_offline, (void *)true,
 248                                     (void **)&errdev);
 249                 if (!errdev || acpi_force_hot_remove)
 250                         acpi_bus_offline(handle, 0, (void *)true,
 251                                          (void **)&errdev);
 252
 253                 if (errdev && !acpi_force_hot_remove) {
 254                         dev_warn(errdev, "Offline failed.\n");
 255                         acpi_bus_online(handle, 0, NULL, NULL);
 256                         acpi_walk_namespace(ACPI_TYPE_ANY, handle,
 257                                             ACPI_UINT32_MAX, acpi_bus_online,
 258                                             NULL, NULL, NULL);
 259                         return -EBUSY;
 260                 }
 261         }
 262         return 0;
 263 }
 264
 265 static int acpi_scan_hot_remove(struct acpi_device *device)
 266 {
 267         acpi_handle handle = device->handle;
 268         unsigned long long sta;
 269         acpi_status status;
 270
 271         if (device->handler->hotplug.demand_offline && !acpi_force_hot_remove) {
 272                 if (!acpi_scan_is_offline(device, true))
 273                         return -EBUSY;
 274         } else {
 275                 int error = acpi_scan_try_to_offline(device);
 276                 if (error)
 277                         return error;
 278         }
 279
 280         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 281                 "Hot-removing device %s...\n", dev_name(&device->dev)));
 282
 283         acpi_bus_trim(device);
 284
 285         acpi_evaluate_lck(handle, 0);
 286         /*
 287          * TBD: _EJD support.
 288          */
 289         status = acpi_evaluate_ej0(handle);
 290         if (status == AE_NOT_FOUND)
 291                 return -ENODEV;
 292         else if (ACPI_FAILURE(status))
 293                 return -EIO;
 294
 295         /*
 296          * Verify if eject was indeed successful.  If not, log an error
 297          * message.  No need to call _OST since _EJ0 call was made OK.
 298          */
 299         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 300         if (ACPI_FAILURE(status)) {
 301                 acpi_handle_warn(handle,
 302                         "Status check after eject failed (0x%x)\n", status);
 303         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
 304                 acpi_handle_warn(handle,
 305                         "Eject incomplete - status 0x%llx\n", sta);
 306         }
 307
 308         return 0;
 309 }
 310
 311 static int acpi_scan_device_not_present(struct acpi_device *adev)
 312 {
 313         if (!acpi_device_enumerated(adev)) {
 314                 dev_warn(&adev->dev, "Still not present\n");
 315                 return -EALREADY;
 316         }
 317         acpi_bus_trim(adev);
 318         return 0;
 319 }
 320
 321 static int acpi_scan_device_check(struct acpi_device *adev)
 322 {
 323         int error;
 324
 325         acpi_bus_get_status(adev);
 326         if (adev->status.present || adev->status.functional) {
 327                 /*
 328                  * This function is only called for device objects for which
 329                  * matching scan handlers exist.  The only situation in which
 330                  * the scan handler is not attached to this device object yet
 331                  * is when the device has just appeared (either it wasn't
 332                  * present at all before or it was removed and then added
 333                  * again).
 334                  */
 335                 if (adev->handler) {
 336                         dev_warn(&adev->dev, "Already enumerated\n");
 337                         return -EALREADY;
 338                 }
 339                 error = acpi_bus_scan(adev->handle);
 340                 if (error) {
 341                         dev_warn(&adev->dev, "Namespace scan failure\n");
 342                         return error;
 343                 }
 344                 if (!adev->handler) {
 345                         dev_warn(&adev->dev, "Enumeration failure\n");
 346                         error = -ENODEV;
 347                 }
 348         } else {
 349                 error = acpi_scan_device_not_present(adev);
 350         }
 351         return error;
 352 }
 353
 354 static int acpi_scan_bus_check(struct acpi_device *adev)
 355 {
 356         struct acpi_scan_handler *handler = adev->handler;
 357         struct acpi_device *child;
 358         int error;
 359
 360         acpi_bus_get_status(adev);
 361         if (!(adev->status.present || adev->status.functional)) {
 362                 acpi_scan_device_not_present(adev);
 363                 return 0;
 364         }
 365         if (handler && handler->hotplug.scan_dependent)
 366                 return handler->hotplug.scan_dependent(adev);
 367
 368         error = acpi_bus_scan(adev->handle);
 369         if (error) {
 370                 dev_warn(&adev->dev, "Namespace scan failure\n");
 371                 return error;
 372         }
 373         list_for_each_entry(child, &adev->children, node) {
 374                 error = acpi_scan_bus_check(child);
 375                 if (error)
 376                         return error;
 377         }
 378         return 0;
 379 }
 380
 381 static void acpi_device_hotplug(void *data, u32 src)
 382 {
 383         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 384         struct acpi_device *adev = data;
 385         int error;
 386
 387         lock_device_hotplug();
 388         mutex_lock(&acpi_scan_lock);
 389
 390         /*
 391          * The device object's ACPI handle cannot become invalid as long as we
 392          * are holding acpi_scan_lock, but it may have become invalid before
 393          * that lock was acquired.
 394          */
 395         if (adev->handle == INVALID_ACPI_HANDLE)
 396                 goto out;
 397
 398         switch (src) {
 399         case ACPI_NOTIFY_BUS_CHECK:
 400                 error = acpi_scan_bus_check(adev);
 401                 break;
 402         case ACPI_NOTIFY_DEVICE_CHECK:
 403                 error = acpi_scan_device_check(adev);
 404                 break;
 405         case ACPI_NOTIFY_EJECT_REQUEST:
 406         case ACPI_OST_EC_OSPM_EJECT:
 407                 error = acpi_scan_hot_remove(adev);
 408                 break;
 409         default:
 410                 error = -EINVAL;
 411                 break;
 412         }
 413         if (!error)
 414                 ost_code = ACPI_OST_SC_SUCCESS;
 415
 416  out:
 417         acpi_evaluate_hotplug_ost(adev->handle, src, ost_code, NULL);
 418         put_device(&adev->dev);
 419         mutex_unlock(&acpi_scan_lock);
 420         unlock_device_hotplug();
 421 }
 422
 423 static void acpi_hotplug_notify_cb(acpi_handle handle, u32 type, void *data)
 424 {
 425         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 426         struct acpi_scan_handler *handler = data;
 427         struct acpi_device *adev;
 428         acpi_status status;
 429
 430         if (acpi_bus_get_device(handle, &adev))
 431                 goto err_out;
 432
 433         switch (type) {
 434         case ACPI_NOTIFY_BUS_CHECK:
 435                 acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
 436                 break;
 437         case ACPI_NOTIFY_DEVICE_CHECK:
 438                 acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
 439                 break;
 440         case ACPI_NOTIFY_EJECT_REQUEST:
 441                 acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
 442                 if (!handler->hotplug.enabled) {
 443                         acpi_handle_err(handle, "Eject disabled\n");
 444                         ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 445                         goto err_out;
 446                 }
 447                 acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST,
 448                                           ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 449                 break;
 450         default:
 451                 /* non-hotplug event; possibly handled by other handler */
 452                 return;
 453         }
 454         get_device(&adev->dev);
 455         status = acpi_hotplug_execute(acpi_device_hotplug, adev, type);
 456         if (ACPI_SUCCESS(status))
 457                 return;
 458
 459         put_device(&adev->dev);
 460
 461  err_out:
 462         acpi_evaluate_hotplug_ost(handle, type, ost_code, NULL);
 463 }
 464
 465 static ssize_t real_power_state_show(struct device *dev,
 466                                      struct device_attribute *attr, char *buf)
 467 {
 468         struct acpi_device *adev = to_acpi_device(dev);
 469         int state;
 470         int ret;
 471
 472         ret = acpi_device_get_power(adev, &state);
 473         if (ret)
 474                 return ret;
 475
 476         return sprintf(buf, "%s\n", acpi_power_state_string(state));
 477 }
 478
 479 static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL);
 480
 481 static ssize_t power_state_show(struct device *dev,
 482                                 struct device_attribute *attr, char *buf)
 483 {
 484         struct acpi_device *adev = to_acpi_device(dev);
 485
 486         return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
 487 }
 488
 489 static DEVICE_ATTR(power_state, 0444, power_state_show, NULL);
 490
 491 static ssize_t
 492 acpi_eject_store(struct device *d, struct device_attribute *attr,
 493                 const char *buf, size_t count)
 494 {
 495         struct acpi_device *acpi_device = to_acpi_device(d);
 496         acpi_object_type not_used;
 497         acpi_status status;
 498
 499         if (!count || buf[0] != '1')
 500                 return -EINVAL;
 501
 502         if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
 503             && !acpi_device->driver)
 504                 return -ENODEV;
 505
 506         status = acpi_get_type(acpi_device->handle, &not_used);
 507         if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
 508                 return -ENODEV;
 509
 510         acpi_evaluate_hotplug_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT,
 511                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 512         get_device(&acpi_device->dev);
 513         status = acpi_hotplug_execute(acpi_device_hotplug, acpi_device,
 514                                       ACPI_OST_EC_OSPM_EJECT);
 515         if (ACPI_SUCCESS(status))
 516                 return count;
 517
 518         put_device(&acpi_device->dev);
 519         acpi_evaluate_hotplug_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT,
 520                                   ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
 521         return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
 522 }
 523
 524 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 525
 526 static ssize_t
 527 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 528         struct acpi_device *acpi_dev = to_acpi_device(dev);
 529
 530         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
 531 }
 532 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 533
 534 static ssize_t acpi_device_uid_show(struct device *dev,
 535                                     struct device_attribute *attr, char *buf)
 536 {
 537         struct acpi_device *acpi_dev = to_acpi_device(dev);
 538
 539         return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
 540 }
 541 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
 542
 543 static ssize_t acpi_device_adr_show(struct device *dev,
 544                                     struct device_attribute *attr, char *buf)
 545 {
 546         struct acpi_device *acpi_dev = to_acpi_device(dev);
 547
 548         return sprintf(buf, "0x%08x\n",
 549                        (unsigned int)(acpi_dev->pnp.bus_address));
 550 }
 551 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
 552
 553 static ssize_t
 554 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 555         struct acpi_device *acpi_dev = to_acpi_device(dev);
 556         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 557         int result;
 558
 559         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 560         if (result)
 561                 goto end;
 562
 563         result = sprintf(buf, "%s\n", (char*)path.pointer);
 564         kfree(path.pointer);
 565 end:
 566         return result;
 567 }
 568 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 569
 570 /* sysfs file that shows description text from the ACPI _STR method */
 571 static ssize_t description_show(struct device *dev,
 572                                 struct device_attribute *attr,
 573                                 char *buf) {
 574         struct acpi_device *acpi_dev = to_acpi_device(dev);
 575         int result;
 576
 577         if (acpi_dev->pnp.str_obj == NULL)
 578                 return 0;
 579
 580         /*
 581          * The _STR object contains a Unicode identifier for a device.
 582          * We need to convert to utf-8 so it can be displayed.
 583          */
 584         result = utf16s_to_utf8s(
 585                 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
 586                 acpi_dev->pnp.str_obj->buffer.length,
 587                 UTF16_LITTLE_ENDIAN, buf,
 588                 PAGE_SIZE);
 589
 590         buf[result++] = '\n';
 591
 592         return result;
 593 }
 594 static DEVICE_ATTR(description, 0444, description_show, NULL);
 595
 596 static ssize_t
 597 acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
 598                      char *buf) {
 599         struct acpi_device *acpi_dev = to_acpi_device(dev);
 600
 601         return sprintf(buf, "%lu\n", acpi_dev->pnp.sun);
 602 }
 603 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
 604
 605 static ssize_t status_show(struct device *dev, struct device_attribute *attr,
 606                                 char *buf) {
 607         struct acpi_device *acpi_dev = to_acpi_device(dev);
 608         acpi_status status;
 609         unsigned long long sta;
 610
 611         status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta);
 612         if (ACPI_FAILURE(status))
 613                 return -ENODEV;
 614
 615         return sprintf(buf, "%llu\n", sta);
 616 }
 617 static DEVICE_ATTR_RO(status);
 618
 619 static int acpi_device_setup_files(struct acpi_device *dev)
 620 {
 621         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 622         acpi_status status;
 623         unsigned long long sun;
 624         int result = 0;
 625
 626         /*
 627          * Devices gotten from FADT don't have a "path" attribute
 628          */
 629         if (dev->handle) {
 630                 result = device_create_file(&dev->dev, &dev_attr_path);
 631                 if (result)
 632                         goto end;
 633         }
 634
 635         if (!list_empty(&dev->pnp.ids)) {
 636                 result = device_create_file(&dev->dev, &dev_attr_hid);
 637                 if (result)
 638                         goto end;
 639
 640                 result = device_create_file(&dev->dev, &dev_attr_modalias);
 641                 if (result)
 642                         goto end;
 643         }
 644
 645         /*
 646          * If device has _STR, 'description' file is created
 647          */
 648         if (acpi_has_method(dev->handle, "_STR")) {
 649                 status = acpi_evaluate_object(dev->handle, "_STR",
 650                                         NULL, &buffer);
 651                 if (ACPI_FAILURE(status))
 652                         buffer.pointer = NULL;
 653                 dev->pnp.str_obj = buffer.pointer;
 654                 result = device_create_file(&dev->dev, &dev_attr_description);
 655                 if (result)
 656                         goto end;
 657         }
 658
 659         if (dev->pnp.type.bus_address)
 660                 result = device_create_file(&dev->dev, &dev_attr_adr);
 661         if (dev->pnp.unique_id)
 662                 result = device_create_file(&dev->dev, &dev_attr_uid);
 663
 664         status = acpi_evaluate_integer(dev->handle, "_SUN", NULL, &sun);
 665         if (ACPI_SUCCESS(status)) {
 666                 dev->pnp.sun = (unsigned long)sun;
 667                 result = device_create_file(&dev->dev, &dev_attr_sun);
 668                 if (result)
 669                         goto end;
 670         } else {
 671                 dev->pnp.sun = (unsigned long)-1;
 672         }
 673
 674         if (acpi_has_method(dev->handle, "_STA")) {
 675                 result = device_create_file(&dev->dev, &dev_attr_status);
 676                 if (result)
 677                         goto end;
 678         }
 679
 680         /*
 681          * If device has _EJ0, 'eject' file is created that is used to trigger
 682          * hot-removal function from userland.
 683          */
 684         if (acpi_has_method(dev->handle, "_EJ0")) {
 685                 result = device_create_file(&dev->dev, &dev_attr_eject);
 686                 if (result)
 687                         return result;
 688         }
 689
 690         if (dev->flags.power_manageable) {
 691                 result = device_create_file(&dev->dev, &dev_attr_power_state);
 692                 if (result)
 693                         return result;
 694
 695                 if (dev->power.flags.power_resources)
 696                         result = device_create_file(&dev->dev,
 697                                                     &dev_attr_real_power_state);
 698         }
 699
 700 end:
 701         return result;
 702 }
 703
 704 static void acpi_device_remove_files(struct acpi_device *dev)
 705 {
 706         if (dev->flags.power_manageable) {
 707                 device_remove_file(&dev->dev, &dev_attr_power_state);
 708                 if (dev->power.flags.power_resources)
 709                         device_remove_file(&dev->dev,
 710                                            &dev_attr_real_power_state);
 711         }
 712
 713         /*
 714          * If device has _STR, remove 'description' file
 715          */
 716         if (acpi_has_method(dev->handle, "_STR")) {
 717                 kfree(dev->pnp.str_obj);
 718                 device_remove_file(&dev->dev, &dev_attr_description);
 719         }
 720         /*
 721          * If device has _EJ0, remove 'eject' file.
 722          */
 723         if (acpi_has_method(dev->handle, "_EJ0"))
 724                 device_remove_file(&dev->dev, &dev_attr_eject);
 725
 726         if (acpi_has_method(dev->handle, "_SUN"))
 727                 device_remove_file(&dev->dev, &dev_attr_sun);
 728
 729         if (dev->pnp.unique_id)
 730                 device_remove_file(&dev->dev, &dev_attr_uid);
 731         if (dev->pnp.type.bus_address)
 732                 device_remove_file(&dev->dev, &dev_attr_adr);
 733         device_remove_file(&dev->dev, &dev_attr_modalias);
 734         device_remove_file(&dev->dev, &dev_attr_hid);
 735         if (acpi_has_method(dev->handle, "_STA"))
 736                 device_remove_file(&dev->dev, &dev_attr_status);
 737         if (dev->handle)
 738                 device_remove_file(&dev->dev, &dev_attr_path);
 739 }
 740 /* --------------------------------------------------------------------------
 741                         ACPI Bus operations
 742    -------------------------------------------------------------------------- */
 743
 744 static const struct acpi_device_id *__acpi_match_device(
 745         struct acpi_device *device, const struct acpi_device_id *ids)
 746 {
 747         const struct acpi_device_id *id;
 748         struct acpi_hardware_id *hwid;
 749
 750         /*
 751          * If the device is not present, it is unnecessary to load device
 752          * driver for it.
 753          */
 754         if (!device->status.present)
 755                 return NULL;
 756
 757         for (id = ids; id->id[0]; id++)
 758                 list_for_each_entry(hwid, &device->pnp.ids, list)
 759                         if (!strcmp((char *) id->id, hwid->id))
 760                                 return id;
 761
 762         return NULL;
 763 }
 764
 765 /**
 766  * acpi_match_device - Match a struct device against a given list of ACPI IDs
 767  * @ids: Array of struct acpi_device_id object to match against.
 768  * @dev: The device structure to match.
 769  *
 770  * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
 771  * object for that handle and use that object to match against a given list of
 772  * device IDs.
 773  *
 774  * Return a pointer to the first matching ID on success or %NULL on failure.
 775  */
 776 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
 777                                                const struct device *dev)
 778 {
 779         struct acpi_device *adev;
 780         acpi_handle handle = ACPI_HANDLE(dev);
 781
 782         if (!ids || !handle || acpi_bus_get_device(handle, &adev))
 783                 return NULL;
 784
 785         return __acpi_match_device(adev, ids);
 786 }
 787 EXPORT_SYMBOL_GPL(acpi_match_device);
 788
 789 int acpi_match_device_ids(struct acpi_device *device,
 790                           const struct acpi_device_id *ids)
 791 {
 792         return __acpi_match_device(device, ids) ? 0 : -ENOENT;
 793 }
 794 EXPORT_SYMBOL(acpi_match_device_ids);
 795
 796 static void acpi_free_power_resources_lists(struct acpi_device *device)
 797 {
 798         int i;
 799
 800         if (device->wakeup.flags.valid)
 801                 acpi_power_resources_list_free(&device->wakeup.resources);
 802
 803         if (!device->flags.power_manageable)
 804                 return;
 805
 806         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 807                 struct acpi_device_power_state *ps = &device->power.states[i];
 808                 acpi_power_resources_list_free(&ps->resources);
 809         }
 810 }
 811
 812 static void acpi_device_release(struct device *dev)
 813 {
 814         struct acpi_device *acpi_dev = to_acpi_device(dev);
 815
 816         acpi_free_pnp_ids(&acpi_dev->pnp);
 817         acpi_free_power_resources_lists(acpi_dev);
 818         kfree(acpi_dev);
 819 }
 820
 821 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 822 {
 823         struct acpi_device *acpi_dev = to_acpi_device(dev);
 824         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 825
 826         return acpi_dev->flags.match_driver
 827                 && !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 828 }
 829
 830 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 831 {
 832         struct acpi_device *acpi_dev = to_acpi_device(dev);
 833         int len;
 834
 835         if (list_empty(&acpi_dev->pnp.ids))
 836                 return 0;
 837
 838         if (add_uevent_var(env, "MODALIAS="))
 839                 return -ENOMEM;
 840         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 841                               sizeof(env->buf) - env->buflen);
 842         if (len >= (sizeof(env->buf) - env->buflen))
 843                 return -ENOMEM;
 844         env->buflen += len;
 845         return 0;
 846 }
 847
 848 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 849 {
 850         struct acpi_device *device = data;
 851
 852         device->driver->ops.notify(device, event);
 853 }
 854
 855 static acpi_status acpi_device_notify_fixed(void *data)
 856 {
 857         struct acpi_device *device = data;
 858
 859         /* Fixed hardware devices have no handles */
 860         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 861         return AE_OK;
 862 }
 863
 864 static int acpi_device_install_notify_handler(struct acpi_device *device)
 865 {
 866         acpi_status status;
 867
 868         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 869                 status =
 870                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 871                                                      acpi_device_notify_fixed,
 872                                                      device);
 873         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 874                 status =
 875                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 876                                                      acpi_device_notify_fixed,
 877                                                      device);
 878         else
 879                 status = acpi_install_notify_handler(device->handle,
 880                                                      ACPI_DEVICE_NOTIFY,
 881                                                      acpi_device_notify,
 882                                                      device);
 883
 884         if (ACPI_FAILURE(status))
 885                 return -EINVAL;
 886         return 0;
 887 }
 888
 889 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 890 {
 891         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 892                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 893                                                 acpi_device_notify_fixed);
 894         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 895                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 896                                                 acpi_device_notify_fixed);
 897         else
 898                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 899                                            acpi_device_notify);
 900 }
 901
 902 static int acpi_device_probe(struct device *dev)
 903 {
 904         struct acpi_device *acpi_dev = to_acpi_device(dev);
 905         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 906         int ret;
 907
 908         if (acpi_dev->handler)
 909                 return -EINVAL;
 910
 911         if (!acpi_drv->ops.add)
 912                 return -ENOSYS;
 913
 914         ret = acpi_drv->ops.add(acpi_dev);
 915         if (ret)
 916                 return ret;
 917
 918         acpi_dev->driver = acpi_drv;
 919         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 920                           "Driver [%s] successfully bound to device [%s]\n",
 921                           acpi_drv->name, acpi_dev->pnp.bus_id));
 922
 923         if (acpi_drv->ops.notify) {
 924                 ret = acpi_device_install_notify_handler(acpi_dev);
 925                 if (ret) {
 926                         if (acpi_drv->ops.remove)
 927                                 acpi_drv->ops.remove(acpi_dev);
 928
 929                         acpi_dev->driver = NULL;
 930                         acpi_dev->driver_data = NULL;
 931                         return ret;
 932                 }
 933         }
 934
 935         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
 936                           acpi_drv->name, acpi_dev->pnp.bus_id));
 937         get_device(dev);
 938         return 0;
 939 }
 940
 941 static int acpi_device_remove(struct device * dev)
 942 {
 943         struct acpi_device *acpi_dev = to_acpi_device(dev);
 944         struct acpi_driver *acpi_drv = acpi_dev->driver;
 945
 946         if (acpi_drv) {
 947                 if (acpi_drv->ops.notify)
 948                         acpi_device_remove_notify_handler(acpi_dev);
 949                 if (acpi_drv->ops.remove)
 950                         acpi_drv->ops.remove(acpi_dev);
 951         }
 952         acpi_dev->driver = NULL;
 953         acpi_dev->driver_data = NULL;
 954
 955         put_device(dev);
 956         return 0;
 957 }
 958
 959 struct bus_type acpi_bus_type = {
 960         .name           = "acpi",
 961         .match          = acpi_bus_match,
 962         .probe          = acpi_device_probe,
 963         .remove         = acpi_device_remove,
 964         .uevent         = acpi_device_uevent,
 965 };
 966
 967 static void acpi_device_del(struct acpi_device *device)
 968 {
 969         mutex_lock(&acpi_device_lock);
 970         if (device->parent)
 971                 list_del(&device->node);
 972
 973         list_del(&device->wakeup_list);
 974         mutex_unlock(&acpi_device_lock);
 975
 976         acpi_power_add_remove_device(device, false);
 977         acpi_device_remove_files(device);
 978         if (device->remove)
 979                 device->remove(device);
 980
 981         device_del(&device->dev);
 982 }
 983
 984 static LIST_HEAD(acpi_device_del_list);
 985 static DEFINE_MUTEX(acpi_device_del_lock);
 986
 987 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
 988 {
 989         for (;;) {
 990                 struct acpi_device *adev;
 991
 992                 mutex_lock(&acpi_device_del_lock);
 993
 994                 if (list_empty(&acpi_device_del_list)) {
 995                         mutex_unlock(&acpi_device_del_lock);
 996                         break;
 997                 }
 998                 adev = list_first_entry(&acpi_device_del_list,
 999                                         struct acpi_device, del_list);
1000                 list_del(&adev->del_list);
1001
1002                 mutex_unlock(&acpi_device_del_lock);
1003
1004                 acpi_device_del(adev);
1005                 /*
1006                  * Drop references to all power resources that might have been
1007                  * used by the device.
1008                  */
1009                 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
1010                 put_device(&adev->dev);
1011         }
1012 }
1013
1014 /**
1015  * acpi_scan_drop_device - Drop an ACPI device object.
1016  * @handle: Handle of an ACPI namespace node, not used.
1017  * @context: Address of the ACPI device object to drop.
1018  *
1019  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
1020  * namespace node the device object pointed to by @context is attached to.
1021  *
1022  * The unregistration is carried out asynchronously to avoid running
1023  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
1024  * ensure the correct ordering (the device objects must be unregistered in the
1025  * same order in which the corresponding namespace nodes are deleted).
1026  */
1027 static void acpi_scan_drop_device(acpi_handle handle, void *context)
1028 {
1029         static DECLARE_WORK(work, acpi_device_del_work_fn);
1030         struct acpi_device *adev = context;
1031
1032         mutex_lock(&acpi_device_del_lock);
1033
1034         /*
1035          * Use the ACPI hotplug workqueue which is ordered, so this work item
1036          * won't run after any hotplug work items submitted subsequently.  That
1037          * prevents attempts to register device objects identical to those being
1038          * deleted from happening concurrently (such attempts result from
1039          * hotplug events handled via the ACPI hotplug workqueue).  It also will
1040          * run after all of the work items submitted previosuly, which helps
1041          * those work items to ensure that they are not accessing stale device
1042          * objects.
1043          */
1044         if (list_empty(&acpi_device_del_list))
1045                 acpi_queue_hotplug_work(&work);
1046
1047         list_add_tail(&adev->del_list, &acpi_device_del_list);
1048         /* Make acpi_ns_validate_handle() return NULL for this handle. */
1049         adev->handle = INVALID_ACPI_HANDLE;
1050
1051         mutex_unlock(&acpi_device_del_lock);
1052 }
1053
1054 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
1055 {
1056         acpi_status status;
1057
1058         if (!device)
1059                 return -EINVAL;
1060
1061         status = acpi_get_data(handle, acpi_scan_drop_device, (void **)device);
1062         if (ACPI_FAILURE(status) || !*device) {
1063                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
1064                                   handle));
1065                 return -ENODEV;
1066         }
1067         return 0;
1068 }
1069 EXPORT_SYMBOL(acpi_bus_get_device);
1070
1071 int acpi_device_add(struct acpi_device *device,
1072                     void (*release)(struct device *))
1073 {
1074         int result;
1075         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
1076         int found = 0;
1077
1078         if (device->handle) {
1079                 acpi_status status;
1080
1081                 status = acpi_attach_data(device->handle, acpi_scan_drop_device,
1082                                           device);
1083                 if (ACPI_FAILURE(status)) {
1084                         acpi_handle_err(device->handle,
1085                                         "Unable to attach device data\n");
1086                         return -ENODEV;
1087                 }
1088         }
1089
1090         /*
1091          * Linkage
1092          * -------
1093          * Link this device to its parent and siblings.
1094          */
1095         INIT_LIST_HEAD(&device->children);
1096         INIT_LIST_HEAD(&device->node);
1097         INIT_LIST_HEAD(&device->wakeup_list);
1098         INIT_LIST_HEAD(&device->physical_node_list);
1099         INIT_LIST_HEAD(&device->del_list);
1100         mutex_init(&device->physical_node_lock);
1101
1102         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
1103         if (!new_bus_id) {
1104                 pr_err(PREFIX "Memory allocation error\n");
1105                 result = -ENOMEM;
1106                 goto err_detach;
1107         }
1108
1109         mutex_lock(&acpi_device_lock);
1110         /*
1111          * Find suitable bus_id and instance number in acpi_bus_id_list
1112          * If failed, create one and link it into acpi_bus_id_list
1113          */
1114         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
1115                 if (!strcmp(acpi_device_bus_id->bus_id,
1116                             acpi_device_hid(device))) {
1117                         acpi_device_bus_id->instance_no++;
1118                         found = 1;
1119                         kfree(new_bus_id);
1120                         break;
1121                 }
1122         }
1123         if (!found) {
1124                 acpi_device_bus_id = new_bus_id;
1125                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
1126                 acpi_device_bus_id->instance_no = 0;
1127                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
1128         }
1129         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
1130
1131         if (device->parent)
1132                 list_add_tail(&device->node, &device->parent->children);
1133
1134         if (device->wakeup.flags.valid)
1135                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
1136         mutex_unlock(&acpi_device_lock);
1137
1138         if (device->parent)
1139                 device->dev.parent = &device->parent->dev;
1140         device->dev.bus = &acpi_bus_type;
1141         device->dev.release = release;
1142         result = device_add(&device->dev);
1143         if (result) {
1144                 dev_err(&device->dev, "Error registering device\n");
1145                 goto err;
1146         }
1147
1148         result = acpi_device_setup_files(device);
1149         if (result)
1150                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
1151                        dev_name(&device->dev));
1152
1153         return 0;
1154
1155  err:
1156         mutex_lock(&acpi_device_lock);
1157         if (device->parent)
1158                 list_del(&device->node);
1159         list_del(&device->wakeup_list);
1160         mutex_unlock(&acpi_device_lock);
1161
1162  err_detach:
1163         acpi_detach_data(device->handle, acpi_scan_drop_device);
1164         return result;
1165 }
1166
1167 /* --------------------------------------------------------------------------
1168                                  Driver Management
1169    -------------------------------------------------------------------------- */
1170 /**
1171  * acpi_bus_register_driver - register a driver with the ACPI bus
1172  * @driver: driver being registered
1173  *
1174  * Registers a driver with the ACPI bus.  Searches the namespace for all
1175  * devices that match the driver's criteria and binds.  Returns zero for
1176  * success or a negative error status for failure.
1177  */
1178 int acpi_bus_register_driver(struct acpi_driver *driver)
1179 {
1180         int ret;
1181
1182         if (acpi_disabled)
1183                 return -ENODEV;
1184         driver->drv.name = driver->name;
1185         driver->drv.bus = &acpi_bus_type;
1186         driver->drv.owner = driver->owner;
1187
1188         ret = driver_register(&driver->drv);
1189         return ret;
1190 }
1191
1192 EXPORT_SYMBOL(acpi_bus_register_driver);
1193
1194 /**
1195  * acpi_bus_unregister_driver - unregisters a driver with the ACPI bus
1196  * @driver: driver to unregister
1197  *
1198  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
1199  * devices that match the driver's criteria and unbinds.
1200  */
1201 void acpi_bus_unregister_driver(struct acpi_driver *driver)
1202 {
1203         driver_unregister(&driver->drv);
1204 }
1205
1206 EXPORT_SYMBOL(acpi_bus_unregister_driver);
1207
1208 /* --------------------------------------------------------------------------
1209                                  Device Enumeration
1210    -------------------------------------------------------------------------- */
1211 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
1212 {
1213         struct acpi_device *device = NULL;
1214         acpi_status status;
1215
1216         /*
1217          * Fixed hardware devices do not appear in the namespace and do not
1218          * have handles, but we fabricate acpi_devices for them, so we have
1219          * to deal with them specially.
1220          */
1221         if (!handle)
1222                 return acpi_root;
1223
1224         do {
1225                 status = acpi_get_parent(handle, &handle);
1226                 if (ACPI_FAILURE(status))
1227                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
1228         } while (acpi_bus_get_device(handle, &device));
1229         return device;
1230 }
1231
1232 acpi_status
1233 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
1234 {
1235         acpi_status status;
1236         acpi_handle tmp;
1237         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
1238         union acpi_object *obj;
1239
1240         status = acpi_get_handle(handle, "_EJD", &tmp);
1241         if (ACPI_FAILURE(status))
1242                 return status;
1243
1244         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
1245         if (ACPI_SUCCESS(status)) {
1246                 obj = buffer.pointer;
1247                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
1248                                          ejd);
1249                 kfree(buffer.pointer);
1250         }
1251         return status;
1252 }
1253 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
1254
1255 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
1256                                         struct acpi_device_wakeup *wakeup)
1257 {
1258         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1259         union acpi_object *package = NULL;
1260         union acpi_object *element = NULL;
1261         acpi_status status;
1262         int err = -ENODATA;
1263
1264         if (!wakeup)
1265                 return -EINVAL;
1266
1267         INIT_LIST_HEAD(&wakeup->resources);
1268
1269         /* _PRW */
1270         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
1271         if (ACPI_FAILURE(status)) {
1272                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
1273                 return err;
1274         }
1275
1276         package = (union acpi_object *)buffer.pointer;
1277
1278         if (!package || package->package.count < 2)
1279                 goto out;
1280
1281         element = &(package->package.elements[0]);
1282         if (!element)
1283                 goto out;
1284
1285         if (element->type == ACPI_TYPE_PACKAGE) {
1286                 if ((element->package.count < 2) ||
1287                     (element->package.elements[0].type !=
1288                      ACPI_TYPE_LOCAL_REFERENCE)
1289                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
1290                         goto out;
1291
1292                 wakeup->gpe_device =
1293                     element->package.elements[0].reference.handle;
1294                 wakeup->gpe_number =
1295                     (u32) element->package.elements[1].integer.value;
1296         } else if (element->type == ACPI_TYPE_INTEGER) {
1297                 wakeup->gpe_device = NULL;
1298                 wakeup->gpe_number = element->integer.value;
1299         } else {
1300                 goto out;
1301         }
1302
1303         element = &(package->package.elements[1]);
1304         if (element->type != ACPI_TYPE_INTEGER)
1305                 goto out;
1306
1307         wakeup->sleep_state = element->integer.value;
1308
1309         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
1310         if (err)
1311                 goto out;
1312
1313         if (!list_empty(&wakeup->resources)) {
1314                 int sleep_state;
1315
1316                 err = acpi_power_wakeup_list_init(&wakeup->resources,
1317                                                   &sleep_state);
1318                 if (err) {
1319                         acpi_handle_warn(handle, "Retrieving current states "
1320                                          "of wakeup power resources failed\n");
1321                         acpi_power_resources_list_free(&wakeup->resources);
1322                         goto out;
1323                 }
1324                 if (sleep_state < wakeup->sleep_state) {
1325                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
1326                                          "(S%d) by S%d from power resources\n",
1327                                          (int)wakeup->sleep_state, sleep_state);
1328                         wakeup->sleep_state = sleep_state;
1329                 }
1330         }
1331         acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
1332
1333  out:
1334         kfree(buffer.pointer);
1335         return err;
1336 }
1337
1338 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
1339 {
1340         struct acpi_device_id button_device_ids[] = {
1341                 {"PNP0C0C", 0},
1342                 {"PNP0C0D", 0},
1343                 {"PNP0C0E", 0},
1344                 {"", 0},
1345         };
1346         acpi_status status;
1347         acpi_event_status event_status;
1348
1349         device->wakeup.flags.notifier_present = 0;
1350
1351         /* Power button, Lid switch always enable wakeup */
1352         if (!acpi_match_device_ids(device, button_device_ids)) {
1353                 device->wakeup.flags.run_wake = 1;
1354                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
1355                         /* Do not use Lid/sleep button for S5 wakeup */
1356                         if (device->wakeup.sleep_state == ACPI_STATE_S5)
1357                                 device->wakeup.sleep_state = ACPI_STATE_S4;
1358                 }
1359                 device_set_wakeup_capable(&device->dev, true);
1360                 return;
1361         }
1362
1363         status = acpi_get_gpe_status(device->wakeup.gpe_device,
1364                                         device->wakeup.gpe_number,
1365                                                 &event_status);
1366         if (status == AE_OK)
1367                 device->wakeup.flags.run_wake =
1368                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
1369 }
1370
1371 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1372 {
1373         int err;
1374
1375         /* Presence of _PRW indicates wake capable */
1376         if (!acpi_has_method(device->handle, "_PRW"))
1377                 return;
1378
1379         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
1380                                                            &device->wakeup);
1381         if (err) {
1382                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
1383                 return;
1384         }
1385
1386         device->wakeup.flags.valid = 1;
1387         device->wakeup.prepare_count = 0;
1388         acpi_bus_set_run_wake_flags(device);
1389         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
1390          * system for the ACPI device with the _PRW object.
1391          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
1392          * So it is necessary to call _DSW object first. Only when it is not
1393          * present will the _PSW object used.
1394          */
1395         err = acpi_device_sleep_wake(device, 0, 0, 0);
1396         if (err)
1397                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1398                                 "error in _DSW or _PSW evaluation\n"));
1399 }
1400
1401 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1402 {
1403         struct acpi_device_power_state *ps = &device->power.states[state];
1404         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1405         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1406         acpi_status status;
1407
1408         INIT_LIST_HEAD(&ps->resources);
1409
1410         /* Evaluate "_PRx" to get referenced power resources */
1411         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1412         if (ACPI_SUCCESS(status)) {
1413                 union acpi_object *package = buffer.pointer;
1414
1415                 if (buffer.length && package
1416                     && package->type == ACPI_TYPE_PACKAGE
1417                     && package->package.count) {
1418                         int err = acpi_extract_power_resources(package, 0,
1419                                                                &ps->resources);
1420                         if (!err)
1421                                 device->power.flags.power_resources = 1;
1422                 }
1423                 ACPI_FREE(buffer.pointer);
1424         }
1425
1426         /* Evaluate "_PSx" to see if we can do explicit sets */
1427         pathname[2] = 'S';
1428         if (acpi_has_method(device->handle, pathname))
1429                 ps->flags.explicit_set = 1;
1430
1431         /*
1432          * State is valid if there are means to put the device into it.
1433          * D3hot is only valid if _PR3 present.
1434          */
1435         if (!list_empty(&ps->resources)
1436             || (ps->flags.explicit_set && state < ACPI_STATE_D3_HOT)) {
1437                 ps->flags.valid = 1;
1438                 ps->flags.os_accessible = 1;
1439         }
1440
1441         ps->power = -1;         /* Unknown - driver assigned */
1442         ps->latency = -1;       /* Unknown - driver assigned */
1443 }
1444
1445 static void acpi_bus_get_power_flags(struct acpi_device *device)
1446 {
1447         u32 i;
1448
1449         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1450         if (!acpi_has_method(device->handle, "_PS0") &&
1451             !acpi_has_method(device->handle, "_PR0"))
1452                 return;
1453
1454         device->flags.power_manageable = 1;
1455
1456         /*
1457          * Power Management Flags
1458          */
1459         if (acpi_has_method(device->handle, "_PSC"))
1460                 device->power.flags.explicit_get = 1;
1461         if (acpi_has_method(device->handle, "_IRC"))
1462                 device->power.flags.inrush_current = 1;
1463
1464         /*
1465          * Enumerate supported power management states
1466          */
1467         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1468                 acpi_bus_init_power_state(device, i);
1469
1470         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1471
1472         /* Set defaults for D0 and D3 states (always valid) */
1473         device->power.states[ACPI_STATE_D0].flags.valid = 1;
1474         device->power.states[ACPI_STATE_D0].power = 100;
1475         device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
1476         device->power.states[ACPI_STATE_D3_COLD].power = 0;
1477
1478         /* Set D3cold's explicit_set flag if _PS3 exists. */
1479         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
1480                 device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
1481
1482         /* Presence of _PS3 or _PRx means we can put the device into D3 cold */
1483         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set ||
1484                         device->power.flags.power_resources)
1485                 device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
1486
1487         if (acpi_bus_init_power(device)) {
1488                 acpi_free_power_resources_lists(device);
1489                 device->flags.power_manageable = 0;
1490         }
1491 }
1492
1493 static void acpi_bus_get_flags(struct acpi_device *device)
1494 {
1495         /* Presence of _STA indicates 'dynamic_status' */
1496         if (acpi_has_method(device->handle, "_STA"))
1497                 device->flags.dynamic_status = 1;
1498
1499         /* Presence of _RMV indicates 'removable' */
1500         if (acpi_has_method(device->handle, "_RMV"))
1501                 device->flags.removable = 1;
1502
1503         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1504         if (acpi_has_method(device->handle, "_EJD") ||
1505             acpi_has_method(device->handle, "_EJ0"))
1506                 device->flags.ejectable = 1;
1507 }
1508
1509 static void acpi_device_get_busid(struct acpi_device *device)
1510 {
1511         char bus_id[5] = { '?', 0 };
1512         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1513         int i = 0;
1514
1515         /*
1516          * Bus ID
1517          * ------
1518          * The device's Bus ID is simply the object name.
1519          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1520          */
1521         if (ACPI_IS_ROOT_DEVICE(device)) {
1522                 strcpy(device->pnp.bus_id, "ACPI");
1523                 return;
1524         }
1525
1526         switch (device->device_type) {
1527         case ACPI_BUS_TYPE_POWER_BUTTON:
1528                 strcpy(device->pnp.bus_id, "PWRF");
1529                 break;
1530         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1531                 strcpy(device->pnp.bus_id, "SLPF");
1532                 break;
1533         default:
1534                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1535                 /* Clean up trailing underscores (if any) */
1536                 for (i = 3; i > 1; i--) {
1537                         if (bus_id[i] == '_')
1538                                 bus_id[i] = '\0';
1539                         else
1540                                 break;
1541                 }
1542                 strcpy(device->pnp.bus_id, bus_id);
1543                 break;
1544         }
1545 }
1546
1547 /*
1548  * acpi_ata_match - see if an acpi object is an ATA device
1549  *
1550  * If an acpi object has one of the ACPI ATA methods defined,
1551  * then we can safely call it an ATA device.
1552  */
1553 bool acpi_ata_match(acpi_handle handle)
1554 {
1555         return acpi_has_method(handle, "_GTF") ||
1556                acpi_has_method(handle, "_GTM") ||
1557                acpi_has_method(handle, "_STM") ||
1558                acpi_has_method(handle, "_SDD");
1559 }
1560
1561 /*
1562  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1563  *
1564  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1565  * then we can safely call it an ejectable drive bay
1566  */
1567 bool acpi_bay_match(acpi_handle handle)
1568 {
1569         acpi_handle phandle;
1570
1571         if (!acpi_has_method(handle, "_EJ0"))
1572                 return false;
1573         if (acpi_ata_match(handle))
1574                 return true;
1575         if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1576                 return false;
1577
1578         return acpi_ata_match(phandle);
1579 }
1580
1581 /*
1582  * acpi_dock_match - see if an acpi object has a _DCK method
1583  */
1584 bool acpi_dock_match(acpi_handle handle)
1585 {
1586         return acpi_has_method(handle, "_DCK");
1587 }
1588
1589 const char *acpi_device_hid(struct acpi_device *device)
1590 {
1591         struct acpi_hardware_id *hid;
1592
1593         if (list_empty(&device->pnp.ids))
1594                 return dummy_hid;
1595
1596         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1597         return hid->id;
1598 }
1599 EXPORT_SYMBOL(acpi_device_hid);
1600
1601 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1602 {
1603         struct acpi_hardware_id *id;
1604
1605         id = kmalloc(sizeof(*id), GFP_KERNEL);
1606         if (!id)
1607                 return;
1608
1609         id->id = kstrdup(dev_id, GFP_KERNEL);
1610         if (!id->id) {
1611                 kfree(id);
1612                 return;
1613         }
1614
1615         list_add_tail(&id->list, &pnp->ids);
1616         pnp->type.hardware_id = 1;
1617 }
1618
1619 /*
1620  * Old IBM workstations have a DSDT bug wherein the SMBus object
1621  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1622  * prefix.  Work around this.
1623  */
1624 static bool acpi_ibm_smbus_match(acpi_handle handle)
1625 {
1626         char node_name[ACPI_PATH_SEGMENT_LENGTH];
1627         struct acpi_buffer path = { sizeof(node_name), node_name };
1628
1629         if (!dmi_name_in_vendors("IBM"))
1630                 return false;
1631
1632         /* Look for SMBS object */
1633         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1634             strcmp("SMBS", path.pointer))
1635                 return false;
1636
1637         /* Does it have the necessary (but misnamed) methods? */
1638         if (acpi_has_method(handle, "SBI") &&
1639             acpi_has_method(handle, "SBR") &&
1640             acpi_has_method(handle, "SBW"))
1641                 return true;
1642
1643         return false;
1644 }
1645
1646 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1647                                 int device_type)
1648 {
1649         acpi_status status;
1650         struct acpi_device_info *info;
1651         struct acpi_pnp_device_id_list *cid_list;
1652         int i;
1653
1654         switch (device_type) {
1655         case ACPI_BUS_TYPE_DEVICE:
1656                 if (handle == ACPI_ROOT_OBJECT) {
1657                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1658                         break;
1659                 }
1660
1661                 status = acpi_get_object_info(handle, &info);
1662                 if (ACPI_FAILURE(status)) {
1663                         pr_err(PREFIX "%s: Error reading device info\n",
1664                                         __func__);
1665                         return;
1666                 }
1667
1668                 if (info->valid & ACPI_VALID_HID)
1669                         acpi_add_id(pnp, info->hardware_id.string);
1670                 if (info->valid & ACPI_VALID_CID) {
1671                         cid_list = &info->compatible_id_list;
1672                         for (i = 0; i < cid_list->count; i++)
1673                                 acpi_add_id(pnp, cid_list->ids[i].string);
1674                 }
1675                 if (info->valid & ACPI_VALID_ADR) {
1676                         pnp->bus_address = info->address;
1677                         pnp->type.bus_address = 1;
1678                 }
1679                 if (info->valid & ACPI_VALID_UID)
1680                         pnp->unique_id = kstrdup(info->unique_id.string,
1681                                                         GFP_KERNEL);
1682
1683                 kfree(info);
1684
1685                 /*
1686                  * Some devices don't reliably have _HIDs & _CIDs, so add
1687                  * synthetic HIDs to make sure drivers can find them.
1688                  */
1689                 if (acpi_is_video_device(handle))
1690                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1691                 else if (acpi_bay_match(handle))
1692                         acpi_add_id(pnp, ACPI_BAY_HID);
1693                 else if (acpi_dock_match(handle))
1694                         acpi_add_id(pnp, ACPI_DOCK_HID);
1695                 else if (acpi_ibm_smbus_match(handle))
1696                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1697                 else if (list_empty(&pnp->ids) && handle == ACPI_ROOT_OBJECT) {
1698                         acpi_add_id(pnp, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1699                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1700                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1701                 }
1702
1703                 break;
1704         case ACPI_BUS_TYPE_POWER:
1705                 acpi_add_id(pnp, ACPI_POWER_HID);
1706                 break;
1707         case ACPI_BUS_TYPE_PROCESSOR:
1708                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1709                 break;
1710         case ACPI_BUS_TYPE_THERMAL:
1711                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1712                 break;
1713         case ACPI_BUS_TYPE_POWER_BUTTON:
1714                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1715                 break;
1716         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1717                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1718                 break;
1719         }
1720 }
1721
1722 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1723 {
1724         struct acpi_hardware_id *id, *tmp;
1725
1726         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1727                 kfree(id->id);
1728                 kfree(id);
1729         }
1730         kfree(pnp->unique_id);
1731 }
1732
1733 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1734                              int type, unsigned long long sta)
1735 {
1736         INIT_LIST_HEAD(&device->pnp.ids);
1737         device->device_type = type;
1738         device->handle = handle;
1739         device->parent = acpi_bus_get_parent(handle);
1740         acpi_set_device_status(device, sta);
1741         acpi_device_get_busid(device);
1742         acpi_set_pnp_ids(handle, &device->pnp, type);
1743         acpi_bus_get_flags(device);
1744         device->flags.match_driver = false;
1745         device->flags.initialized = true;
1746         device->flags.visited = false;
1747         device_initialize(&device->dev);
1748         dev_set_uevent_suppress(&device->dev, true);
1749 }
1750
1751 void acpi_device_add_finalize(struct acpi_device *device)
1752 {
1753         dev_set_uevent_suppress(&device->dev, false);
1754         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1755 }
1756
1757 static int acpi_add_single_object(struct acpi_device **child,
1758                                   acpi_handle handle, int type,
1759                                   unsigned long long sta)
1760 {
1761         int result;
1762         struct acpi_device *device;
1763         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1764
1765         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1766         if (!device) {
1767                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1768                 return -ENOMEM;
1769         }
1770
1771         acpi_init_device_object(device, handle, type, sta);
1772         acpi_bus_get_power_flags(device);
1773         acpi_bus_get_wakeup_device_flags(device);
1774
1775         result = acpi_device_add(device, acpi_device_release);
1776         if (result) {
1777                 acpi_device_release(&device->dev);
1778                 return result;
1779         }
1780
1781         acpi_power_add_remove_device(device, true);
1782         acpi_device_add_finalize(device);
1783         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1784         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1785                 dev_name(&device->dev), (char *) buffer.pointer,
1786                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1787         kfree(buffer.pointer);
1788         *child = device;
1789         return 0;
1790 }
1791
1792 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1793                                     unsigned long long *sta)
1794 {
1795         acpi_status status;
1796         acpi_object_type acpi_type;
1797
1798         status = acpi_get_type(handle, &acpi_type);
1799         if (ACPI_FAILURE(status))
1800                 return -ENODEV;
1801
1802         switch (acpi_type) {
1803         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1804         case ACPI_TYPE_DEVICE:
1805                 *type = ACPI_BUS_TYPE_DEVICE;
1806                 status = acpi_bus_get_status_handle(handle, sta);
1807                 if (ACPI_FAILURE(status))
1808                         return -ENODEV;
1809                 break;
1810         case ACPI_TYPE_PROCESSOR:
1811                 *type = ACPI_BUS_TYPE_PROCESSOR;
1812                 status = acpi_bus_get_status_handle(handle, sta);
1813                 if (ACPI_FAILURE(status))
1814                         return -ENODEV;
1815                 break;
1816         case ACPI_TYPE_THERMAL:
1817                 *type = ACPI_BUS_TYPE_THERMAL;
1818                 *sta = ACPI_STA_DEFAULT;
1819                 break;
1820         case ACPI_TYPE_POWER:
1821                 *type = ACPI_BUS_TYPE_POWER;
1822                 *sta = ACPI_STA_DEFAULT;
1823                 break;
1824         default:
1825                 return -ENODEV;
1826         }
1827
1828         return 0;
1829 }
1830
1831 bool acpi_device_is_present(struct acpi_device *adev)
1832 {
1833         if (adev->status.present || adev->status.functional)
1834                 return true;
1835
1836         adev->flags.initialized = false;
1837         return false;
1838 }
1839
1840 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1841                                        char *idstr,
1842                                        const struct acpi_device_id **matchid)
1843 {
1844         const struct acpi_device_id *devid;
1845
1846         for (devid = handler->ids; devid->id[0]; devid++)
1847                 if (!strcmp((char *)devid->id, idstr)) {
1848                         if (matchid)
1849                                 *matchid = devid;
1850
1851                         return true;
1852                 }
1853
1854         return false;
1855 }
1856
1857 static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr,
1858                                         const struct acpi_device_id **matchid)
1859 {
1860         struct acpi_scan_handler *handler;
1861
1862         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1863                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1864                         return handler;
1865
1866         return NULL;
1867 }
1868
1869 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1870 {
1871         if (!!hotplug->enabled == !!val)
1872                 return;
1873
1874         mutex_lock(&acpi_scan_lock);
1875
1876         hotplug->enabled = val;
1877
1878         mutex_unlock(&acpi_scan_lock);
1879 }
1880
1881 static void acpi_scan_init_hotplug(acpi_handle handle, int type)
1882 {
1883         struct acpi_device_pnp pnp = {};
1884         struct acpi_hardware_id *hwid;
1885         struct acpi_scan_handler *handler;
1886
1887         INIT_LIST_HEAD(&pnp.ids);
1888         acpi_set_pnp_ids(handle, &pnp, type);
1889
1890         if (!pnp.type.hardware_id)
1891                 goto out;
1892
1893         /*
1894          * This relies on the fact that acpi_install_notify_handler() will not
1895          * install the same notify handler routine twice for the same handle.
1896          */
1897         list_for_each_entry(hwid, &pnp.ids, list) {
1898                 handler = acpi_scan_match_handler(hwid->id, NULL);
1899                 if (handler) {
1900                         acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
1901                                         acpi_hotplug_notify_cb, handler);
1902                         break;
1903                 }
1904         }
1905
1906 out:
1907         acpi_free_pnp_ids(&pnp);
1908 }
1909
1910 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1911                                       void *not_used, void **return_value)
1912 {
1913         struct acpi_device *device = NULL;
1914         int type;
1915         unsigned long long sta;
1916         int result;
1917
1918         acpi_bus_get_device(handle, &device);
1919         if (device)
1920                 goto out;
1921
1922         result = acpi_bus_type_and_status(handle, &type, &sta);
1923         if (result)
1924                 return AE_OK;
1925
1926         if (type == ACPI_BUS_TYPE_POWER) {
1927                 acpi_add_power_resource(handle);
1928                 return AE_OK;
1929         }
1930
1931         acpi_scan_init_hotplug(handle, type);
1932
1933         acpi_add_single_object(&device, handle, type, sta);
1934         if (!device)
1935                 return AE_CTRL_DEPTH;
1936
1937  out:
1938         if (!*return_value)
1939                 *return_value = device;
1940
1941         return AE_OK;
1942 }
1943
1944 static int acpi_scan_attach_handler(struct acpi_device *device)
1945 {
1946         struct acpi_hardware_id *hwid;
1947         int ret = 0;
1948
1949         list_for_each_entry(hwid, &device->pnp.ids, list) {
1950                 const struct acpi_device_id *devid;
1951                 struct acpi_scan_handler *handler;
1952
1953                 handler = acpi_scan_match_handler(hwid->id, &devid);
1954                 if (handler) {
1955                         ret = handler->attach(device, devid);
1956                         if (ret > 0) {
1957                                 device->handler = handler;
1958                                 break;
1959                         } else if (ret < 0) {
1960                                 break;
1961                         }
1962                 }
1963         }
1964         return ret;
1965 }
1966
1967 static void acpi_bus_attach(struct acpi_device *device)
1968 {
1969         struct acpi_device *child;
1970         int ret;
1971
1972         acpi_bus_get_status(device);
1973         /* Skip devices that are not present. */
1974         if (!acpi_device_is_present(device)) {
1975                 device->flags.visited = false;
1976                 return;
1977         }
1978         if (device->handler)
1979                 goto ok;
1980
1981         if (!device->flags.initialized) {
1982                 acpi_bus_update_power(device, NULL);
1983                 device->flags.initialized = true;
1984         }
1985         device->flags.visited = false;
1986         ret = acpi_scan_attach_handler(device);
1987         if (ret < 0)
1988                 return;
1989
1990         device->flags.match_driver = true;
1991         if (!ret) {
1992                 ret = device_attach(&device->dev);
1993                 if (ret < 0)
1994                         return;
1995         }
1996         device->flags.visited = true;
1997
1998  ok:
1999         list_for_each_entry(child, &device->children, node)
2000                 acpi_bus_attach(child);
2001 }
2002
2003 /**
2004  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2005  * @handle: Root of the namespace scope to scan.
2006  *
2007  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2008  * found devices.
2009  *
2010  * If no devices were found, -ENODEV is returned, but it does not mean that
2011  * there has been a real error.  There just have been no suitable ACPI objects
2012  * in the table trunk from which the kernel could create a device and add an
2013  * appropriate driver.
2014  *
2015  * Must be called under acpi_scan_lock.
2016  */
2017 int acpi_bus_scan(acpi_handle handle)
2018 {
2019         void *device = NULL;
2020
2021         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
2022                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2023                                     acpi_bus_check_add, NULL, NULL, &device);
2024
2025         if (device) {
2026                 acpi_bus_attach(device);
2027                 return 0;
2028         }
2029         return -ENODEV;
2030 }
2031 EXPORT_SYMBOL(acpi_bus_scan);
2032
2033 /**
2034  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2035  * @adev: Root of the ACPI namespace scope to walk.
2036  *
2037  * Must be called under acpi_scan_lock.
2038  */
2039 void acpi_bus_trim(struct acpi_device *adev)
2040 {
2041         struct acpi_scan_handler *handler = adev->handler;
2042         struct acpi_device *child;
2043
2044         list_for_each_entry_reverse(child, &adev->children, node)
2045                 acpi_bus_trim(child);
2046
2047         adev->flags.match_driver = false;
2048         if (handler) {
2049                 if (handler->detach)
2050                         handler->detach(adev);
2051
2052                 adev->handler = NULL;
2053         } else {
2054                 device_release_driver(&adev->dev);
2055         }
2056         /*
2057          * Most likely, the device is going away, so put it into D3cold before
2058          * that.
2059          */
2060         acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2061         adev->flags.initialized = false;
2062         adev->flags.visited = false;
2063 }
2064 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2065
2066 static int acpi_bus_scan_fixed(void)
2067 {
2068         int result = 0;
2069
2070         /*
2071          * Enumerate all fixed-feature devices.
2072          */
2073         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2074                 struct acpi_device *device = NULL;
2075
2076                 result = acpi_add_single_object(&device, NULL,
2077                                                 ACPI_BUS_TYPE_POWER_BUTTON,
2078                                                 ACPI_STA_DEFAULT);
2079                 if (result)
2080                         return result;
2081
2082                 device->flags.match_driver = true;
2083                 result = device_attach(&device->dev);
2084                 if (result < 0)
2085                         return result;
2086
2087                 device_init_wakeup(&device->dev, true);
2088         }
2089
2090         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2091                 struct acpi_device *device = NULL;
2092
2093                 result = acpi_add_single_object(&device, NULL,
2094                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2095                                                 ACPI_STA_DEFAULT);
2096                 if (result)
2097                         return result;
2098
2099                 device->flags.match_driver = true;
2100                 result = device_attach(&device->dev);
2101         }
2102
2103         return result < 0 ? result : 0;
2104 }
2105
2106 int __init acpi_scan_init(void)
2107 {
2108         int result;
2109
2110         result = bus_register(&acpi_bus_type);
2111         if (result) {
2112                 /* We don't want to quit even if we failed to add suspend/resume */
2113                 printk(KERN_ERR PREFIX "Could not register bus type\n");
2114         }
2115
2116         acpi_pci_root_init();
2117         acpi_pci_link_init();
2118         acpi_processor_init();
2119         acpi_platform_init();
2120         acpi_lpss_init();
2121         acpi_cmos_rtc_init();
2122         acpi_container_init();
2123         acpi_memory_hotplug_init();
2124         acpi_dock_init();
2125
2126         mutex_lock(&acpi_scan_lock);
2127         /*
2128          * Enumerate devices in the ACPI namespace.
2129          */
2130         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2131         if (result)
2132                 goto out;
2133
2134         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2135         if (result)
2136                 goto out;
2137
2138         result = acpi_bus_scan_fixed();
2139         if (result) {
2140                 acpi_detach_data(acpi_root->handle, acpi_scan_drop_device);
2141                 acpi_device_del(acpi_root);
2142                 put_device(&acpi_root->dev);
2143                 goto out;
2144         }
2145
2146         acpi_update_all_gpes();
2147
2148  out:
2149         mutex_unlock(&acpi_scan_lock);
2150         return result;
2151 }