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  * Return: 0: no _HID and no _CID
  90  *         -EINVAL: output error
  91  *         -ENOMEM: output is truncated
  92 */
  93 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
  94                            int size)
  95 {
  96         int len;
  97         int count;
  98         struct acpi_hardware_id *id;
  99
 100         if (list_empty(&acpi_dev->pnp.ids))
 101                 return 0;
 102
 103         len = snprintf(modalias, size, "acpi:");
 104         size -= len;
 105
 106         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
 107                 count = snprintf(&modalias[len], size, "%s:", id->id);
 108                 if (count < 0)
 109                         return EINVAL;
 110                 if (count >= size)
 111                         return -ENOMEM;
 112                 len += count;
 113                 size -= count;
 114         }
 115
 116         modalias[len] = '\0';
 117         return len;
 118 }
 119
 120 /*
 121  * Creates uevent modalias field for ACPI enumerated devices.
 122  * Because the other buses does not support ACPI HIDs & CIDs.
 123  * e.g. for a device with hid:IBM0001 and cid:ACPI0001 you get:
 124  * "acpi:IBM0001:ACPI0001"
 125  */
 126 int acpi_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
 127 {
 128         struct acpi_device *acpi_dev;
 129         int len;
 130
 131         acpi_dev = ACPI_COMPANION(dev);
 132         if (!acpi_dev)
 133                 return -ENODEV;
 134
 135         /* Fall back to bus specific way of modalias exporting */
 136         if (list_empty(&acpi_dev->pnp.ids))
 137                 return -ENODEV;
 138
 139         if (add_uevent_var(env, "MODALIAS="))
 140                 return -ENOMEM;
 141         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 142                                 sizeof(env->buf) - env->buflen);
 143         if (len <= 0)
 144                 return len;
 145         env->buflen += len;
 146         return 0;
 147 }
 148 EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias);
 149
 150 /*
 151  * Creates modalias sysfs attribute for ACPI enumerated devices.
 152  * Because the other buses does not support ACPI HIDs & CIDs.
 153  * e.g. for a device with hid:IBM0001 and cid:ACPI0001 you get:
 154  * "acpi:IBM0001:ACPI0001"
 155  */
 156 int acpi_device_modalias(struct device *dev, char *buf, int size)
 157 {
 158         struct acpi_device *acpi_dev;
 159         int len;
 160
 161         acpi_dev = ACPI_COMPANION(dev);
 162         if (!acpi_dev)
 163                 return -ENODEV;
 164
 165         /* Fall back to bus specific way of modalias exporting */
 166         if (list_empty(&acpi_dev->pnp.ids))
 167                 return -ENODEV;
 168
 169         len = create_modalias(acpi_dev, buf, size -1);
 170         if (len <= 0)
 171                 return len;
 172         buf[len++] = '\n';
 173         return len;
 174 }
 175 EXPORT_SYMBOL_GPL(acpi_device_modalias);
 176
 177 static ssize_t
 178 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
 179         struct acpi_device *acpi_dev = to_acpi_device(dev);
 180         int len;
 181
 182         len = create_modalias(acpi_dev, buf, 1024);
 183         if (len <= 0)
 184                 return len;
 185         buf[len++] = '\n';
 186         return len;
 187 }
 188 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
 189
 190 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
 191 {
 192         struct acpi_device_physical_node *pn;
 193         bool offline = true;
 194
 195         mutex_lock(&adev->physical_node_lock);
 196
 197         list_for_each_entry(pn, &adev->physical_node_list, node)
 198                 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
 199                         if (uevent)
 200                                 kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
 201
 202                         offline = false;
 203                         break;
 204                 }
 205
 206         mutex_unlock(&adev->physical_node_lock);
 207         return offline;
 208 }
 209
 210 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
 211                                     void **ret_p)
 212 {
 213         struct acpi_device *device = NULL;
 214         struct acpi_device_physical_node *pn;
 215         bool second_pass = (bool)data;
 216         acpi_status status = AE_OK;
 217
 218         if (acpi_bus_get_device(handle, &device))
 219                 return AE_OK;
 220
 221         if (device->handler && !device->handler->hotplug.enabled) {
 222                 *ret_p = &device->dev;
 223                 return AE_SUPPORT;
 224         }
 225
 226         mutex_lock(&device->physical_node_lock);
 227
 228         list_for_each_entry(pn, &device->physical_node_list, node) {
 229                 int ret;
 230
 231                 if (second_pass) {
 232                         /* Skip devices offlined by the first pass. */
 233                         if (pn->put_online)
 234                                 continue;
 235                 } else {
 236                         pn->put_online = false;
 237                 }
 238                 ret = device_offline(pn->dev);
 239                 if (acpi_force_hot_remove)
 240                         continue;
 241
 242                 if (ret >= 0) {
 243                         pn->put_online = !ret;
 244                 } else {
 245                         *ret_p = pn->dev;
 246                         if (second_pass) {
 247                                 status = AE_ERROR;
 248                                 break;
 249                         }
 250                 }
 251         }
 252
 253         mutex_unlock(&device->physical_node_lock);
 254
 255         return status;
 256 }
 257
 258 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
 259                                    void **ret_p)
 260 {
 261         struct acpi_device *device = NULL;
 262         struct acpi_device_physical_node *pn;
 263
 264         if (acpi_bus_get_device(handle, &device))
 265                 return AE_OK;
 266
 267         mutex_lock(&device->physical_node_lock);
 268
 269         list_for_each_entry(pn, &device->physical_node_list, node)
 270                 if (pn->put_online) {
 271                         device_online(pn->dev);
 272                         pn->put_online = false;
 273                 }
 274
 275         mutex_unlock(&device->physical_node_lock);
 276
 277         return AE_OK;
 278 }
 279
 280 static int acpi_scan_try_to_offline(struct acpi_device *device)
 281 {
 282         acpi_handle handle = device->handle;
 283         struct device *errdev = NULL;
 284         acpi_status status;
 285
 286         /*
 287          * Carry out two passes here and ignore errors in the first pass,
 288          * because if the devices in question are memory blocks and
 289          * CONFIG_MEMCG is set, one of the blocks may hold data structures
 290          * that the other blocks depend on, but it is not known in advance which
 291          * block holds them.
 292          *
 293          * If the first pass is successful, the second one isn't needed, though.
 294          */
 295         status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 296                                      NULL, acpi_bus_offline, (void *)false,
 297                                      (void **)&errdev);
 298         if (status == AE_SUPPORT) {
 299                 dev_warn(errdev, "Offline disabled.\n");
 300                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 301                                     acpi_bus_online, NULL, NULL, NULL);
 302                 return -EPERM;
 303         }
 304         acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
 305         if (errdev) {
 306                 errdev = NULL;
 307                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 308                                     NULL, acpi_bus_offline, (void *)true,
 309                                     (void **)&errdev);
 310                 if (!errdev || acpi_force_hot_remove)
 311                         acpi_bus_offline(handle, 0, (void *)true,
 312                                          (void **)&errdev);
 313
 314                 if (errdev && !acpi_force_hot_remove) {
 315                         dev_warn(errdev, "Offline failed.\n");
 316                         acpi_bus_online(handle, 0, NULL, NULL);
 317                         acpi_walk_namespace(ACPI_TYPE_ANY, handle,
 318                                             ACPI_UINT32_MAX, acpi_bus_online,
 319                                             NULL, NULL, NULL);
 320                         return -EBUSY;
 321                 }
 322         }
 323         return 0;
 324 }
 325
 326 static int acpi_scan_hot_remove(struct acpi_device *device)
 327 {
 328         acpi_handle handle = device->handle;
 329         unsigned long long sta;
 330         acpi_status status;
 331
 332         if (device->handler->hotplug.demand_offline && !acpi_force_hot_remove) {
 333                 if (!acpi_scan_is_offline(device, true))
 334                         return -EBUSY;
 335         } else {
 336                 int error = acpi_scan_try_to_offline(device);
 337                 if (error)
 338                         return error;
 339         }
 340
 341         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 342                 "Hot-removing device %s...\n", dev_name(&device->dev)));
 343
 344         acpi_bus_trim(device);
 345
 346         acpi_evaluate_lck(handle, 0);
 347         /*
 348          * TBD: _EJD support.
 349          */
 350         status = acpi_evaluate_ej0(handle);
 351         if (status == AE_NOT_FOUND)
 352                 return -ENODEV;
 353         else if (ACPI_FAILURE(status))
 354                 return -EIO;
 355
 356         /*
 357          * Verify if eject was indeed successful.  If not, log an error
 358          * message.  No need to call _OST since _EJ0 call was made OK.
 359          */
 360         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 361         if (ACPI_FAILURE(status)) {
 362                 acpi_handle_warn(handle,
 363                         "Status check after eject failed (0x%x)\n", status);
 364         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
 365                 acpi_handle_warn(handle,
 366                         "Eject incomplete - status 0x%llx\n", sta);
 367         }
 368
 369         return 0;
 370 }
 371
 372 static int acpi_scan_device_not_present(struct acpi_device *adev)
 373 {
 374         if (!acpi_device_enumerated(adev)) {
 375                 dev_warn(&adev->dev, "Still not present\n");
 376                 return -EALREADY;
 377         }
 378         acpi_bus_trim(adev);
 379         return 0;
 380 }
 381
 382 static int acpi_scan_device_check(struct acpi_device *adev)
 383 {
 384         int error;
 385
 386         acpi_bus_get_status(adev);
 387         if (adev->status.present || adev->status.functional) {
 388                 /*
 389                  * This function is only called for device objects for which
 390                  * matching scan handlers exist.  The only situation in which
 391                  * the scan handler is not attached to this device object yet
 392                  * is when the device has just appeared (either it wasn't
 393                  * present at all before or it was removed and then added
 394                  * again).
 395                  */
 396                 if (adev->handler) {
 397                         dev_warn(&adev->dev, "Already enumerated\n");
 398                         return -EALREADY;
 399                 }
 400                 error = acpi_bus_scan(adev->handle);
 401                 if (error) {
 402                         dev_warn(&adev->dev, "Namespace scan failure\n");
 403                         return error;
 404                 }
 405                 if (!adev->handler) {
 406                         dev_warn(&adev->dev, "Enumeration failure\n");
 407                         error = -ENODEV;
 408                 }
 409         } else {
 410                 error = acpi_scan_device_not_present(adev);
 411         }
 412         return error;
 413 }
 414
 415 static int acpi_scan_bus_check(struct acpi_device *adev)
 416 {
 417         struct acpi_scan_handler *handler = adev->handler;
 418         struct acpi_device *child;
 419         int error;
 420
 421         acpi_bus_get_status(adev);
 422         if (!(adev->status.present || adev->status.functional)) {
 423                 acpi_scan_device_not_present(adev);
 424                 return 0;
 425         }
 426         if (handler && handler->hotplug.scan_dependent)
 427                 return handler->hotplug.scan_dependent(adev);
 428
 429         error = acpi_bus_scan(adev->handle);
 430         if (error) {
 431                 dev_warn(&adev->dev, "Namespace scan failure\n");
 432                 return error;
 433         }
 434         list_for_each_entry(child, &adev->children, node) {
 435                 error = acpi_scan_bus_check(child);
 436                 if (error)
 437                         return error;
 438         }
 439         return 0;
 440 }
 441
 442 static void acpi_device_hotplug(void *data, u32 src)
 443 {
 444         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 445         struct acpi_device *adev = data;
 446         int error;
 447
 448         lock_device_hotplug();
 449         mutex_lock(&acpi_scan_lock);
 450
 451         /*
 452          * The device object's ACPI handle cannot become invalid as long as we
 453          * are holding acpi_scan_lock, but it may have become invalid before
 454          * that lock was acquired.
 455          */
 456         if (adev->handle == INVALID_ACPI_HANDLE)
 457                 goto out;
 458
 459         switch (src) {
 460         case ACPI_NOTIFY_BUS_CHECK:
 461                 error = acpi_scan_bus_check(adev);
 462                 break;
 463         case ACPI_NOTIFY_DEVICE_CHECK:
 464                 error = acpi_scan_device_check(adev);
 465                 break;
 466         case ACPI_NOTIFY_EJECT_REQUEST:
 467         case ACPI_OST_EC_OSPM_EJECT:
 468                 error = acpi_scan_hot_remove(adev);
 469                 break;
 470         default:
 471                 error = -EINVAL;
 472                 break;
 473         }
 474         if (!error)
 475                 ost_code = ACPI_OST_SC_SUCCESS;
 476
 477  out:
 478         acpi_evaluate_hotplug_ost(adev->handle, src, ost_code, NULL);
 479         put_device(&adev->dev);
 480         mutex_unlock(&acpi_scan_lock);
 481         unlock_device_hotplug();
 482 }
 483
 484 static void acpi_hotplug_notify_cb(acpi_handle handle, u32 type, void *data)
 485 {
 486         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 487         struct acpi_device *adev;
 488         acpi_status status;
 489
 490         if (acpi_bus_get_device(handle, &adev))
 491                 goto err_out;
 492
 493         switch (type) {
 494         case ACPI_NOTIFY_BUS_CHECK:
 495                 acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
 496                 break;
 497         case ACPI_NOTIFY_DEVICE_CHECK:
 498                 acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
 499                 break;
 500         case ACPI_NOTIFY_EJECT_REQUEST:
 501                 acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
 502                 if (!adev->handler)
 503                         goto err_out;
 504
 505                 if (!adev->handler->hotplug.enabled) {
 506                         acpi_handle_err(handle, "Eject disabled\n");
 507                         ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 508                         goto err_out;
 509                 }
 510                 acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST,
 511                                           ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 512                 break;
 513         default:
 514                 /* non-hotplug event; possibly handled by other handler */
 515                 return;
 516         }
 517         get_device(&adev->dev);
 518         status = acpi_hotplug_execute(acpi_device_hotplug, adev, type);
 519         if (ACPI_SUCCESS(status))
 520                 return;
 521
 522         put_device(&adev->dev);
 523
 524  err_out:
 525         acpi_evaluate_hotplug_ost(handle, type, ost_code, NULL);
 526 }
 527
 528 static ssize_t real_power_state_show(struct device *dev,
 529                                      struct device_attribute *attr, char *buf)
 530 {
 531         struct acpi_device *adev = to_acpi_device(dev);
 532         int state;
 533         int ret;
 534
 535         ret = acpi_device_get_power(adev, &state);
 536         if (ret)
 537                 return ret;
 538
 539         return sprintf(buf, "%s\n", acpi_power_state_string(state));
 540 }
 541
 542 static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL);
 543
 544 static ssize_t power_state_show(struct device *dev,
 545                                 struct device_attribute *attr, char *buf)
 546 {
 547         struct acpi_device *adev = to_acpi_device(dev);
 548
 549         return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
 550 }
 551
 552 static DEVICE_ATTR(power_state, 0444, power_state_show, NULL);
 553
 554 static ssize_t
 555 acpi_eject_store(struct device *d, struct device_attribute *attr,
 556                 const char *buf, size_t count)
 557 {
 558         struct acpi_device *acpi_device = to_acpi_device(d);
 559         acpi_object_type not_used;
 560         acpi_status status;
 561
 562         if (!count || buf[0] != '1')
 563                 return -EINVAL;
 564
 565         if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
 566             && !acpi_device->driver)
 567                 return -ENODEV;
 568
 569         status = acpi_get_type(acpi_device->handle, &not_used);
 570         if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
 571                 return -ENODEV;
 572
 573         acpi_evaluate_hotplug_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT,
 574                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 575         get_device(&acpi_device->dev);
 576         status = acpi_hotplug_execute(acpi_device_hotplug, acpi_device,
 577                                       ACPI_OST_EC_OSPM_EJECT);
 578         if (ACPI_SUCCESS(status))
 579                 return count;
 580
 581         put_device(&acpi_device->dev);
 582         acpi_evaluate_hotplug_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT,
 583                                   ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
 584         return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
 585 }
 586
 587 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 588
 589 static ssize_t
 590 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 591         struct acpi_device *acpi_dev = to_acpi_device(dev);
 592
 593         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
 594 }
 595 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 596
 597 static ssize_t acpi_device_uid_show(struct device *dev,
 598                                     struct device_attribute *attr, char *buf)
 599 {
 600         struct acpi_device *acpi_dev = to_acpi_device(dev);
 601
 602         return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
 603 }
 604 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
 605
 606 static ssize_t acpi_device_adr_show(struct device *dev,
 607                                     struct device_attribute *attr, char *buf)
 608 {
 609         struct acpi_device *acpi_dev = to_acpi_device(dev);
 610
 611         return sprintf(buf, "0x%08x\n",
 612                        (unsigned int)(acpi_dev->pnp.bus_address));
 613 }
 614 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
 615
 616 static ssize_t
 617 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 618         struct acpi_device *acpi_dev = to_acpi_device(dev);
 619         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 620         int result;
 621
 622         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 623         if (result)
 624                 goto end;
 625
 626         result = sprintf(buf, "%s\n", (char*)path.pointer);
 627         kfree(path.pointer);
 628 end:
 629         return result;
 630 }
 631 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 632
 633 /* sysfs file that shows description text from the ACPI _STR method */
 634 static ssize_t description_show(struct device *dev,
 635                                 struct device_attribute *attr,
 636                                 char *buf) {
 637         struct acpi_device *acpi_dev = to_acpi_device(dev);
 638         int result;
 639
 640         if (acpi_dev->pnp.str_obj == NULL)
 641                 return 0;
 642
 643         /*
 644          * The _STR object contains a Unicode identifier for a device.
 645          * We need to convert to utf-8 so it can be displayed.
 646          */
 647         result = utf16s_to_utf8s(
 648                 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
 649                 acpi_dev->pnp.str_obj->buffer.length,
 650                 UTF16_LITTLE_ENDIAN, buf,
 651                 PAGE_SIZE);
 652
 653         buf[result++] = '\n';
 654
 655         return result;
 656 }
 657 static DEVICE_ATTR(description, 0444, description_show, NULL);
 658
 659 static ssize_t
 660 acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
 661                      char *buf) {
 662         struct acpi_device *acpi_dev = to_acpi_device(dev);
 663
 664         return sprintf(buf, "%lu\n", acpi_dev->pnp.sun);
 665 }
 666 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
 667
 668 static ssize_t status_show(struct device *dev, struct device_attribute *attr,
 669                                 char *buf) {
 670         struct acpi_device *acpi_dev = to_acpi_device(dev);
 671         acpi_status status;
 672         unsigned long long sta;
 673
 674         status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta);
 675         if (ACPI_FAILURE(status))
 676                 return -ENODEV;
 677
 678         return sprintf(buf, "%llu\n", sta);
 679 }
 680 static DEVICE_ATTR_RO(status);
 681
 682 static int acpi_device_setup_files(struct acpi_device *dev)
 683 {
 684         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 685         acpi_status status;
 686         unsigned long long sun;
 687         int result = 0;
 688
 689         /*
 690          * Devices gotten from FADT don't have a "path" attribute
 691          */
 692         if (dev->handle) {
 693                 result = device_create_file(&dev->dev, &dev_attr_path);
 694                 if (result)
 695                         goto end;
 696         }
 697
 698         if (!list_empty(&dev->pnp.ids)) {
 699                 result = device_create_file(&dev->dev, &dev_attr_hid);
 700                 if (result)
 701                         goto end;
 702
 703                 result = device_create_file(&dev->dev, &dev_attr_modalias);
 704                 if (result)
 705                         goto end;
 706         }
 707
 708         /*
 709          * If device has _STR, 'description' file is created
 710          */
 711         if (acpi_has_method(dev->handle, "_STR")) {
 712                 status = acpi_evaluate_object(dev->handle, "_STR",
 713                                         NULL, &buffer);
 714                 if (ACPI_FAILURE(status))
 715                         buffer.pointer = NULL;
 716                 dev->pnp.str_obj = buffer.pointer;
 717                 result = device_create_file(&dev->dev, &dev_attr_description);
 718                 if (result)
 719                         goto end;
 720         }
 721
 722         if (dev->pnp.type.bus_address)
 723                 result = device_create_file(&dev->dev, &dev_attr_adr);
 724         if (dev->pnp.unique_id)
 725                 result = device_create_file(&dev->dev, &dev_attr_uid);
 726
 727         status = acpi_evaluate_integer(dev->handle, "_SUN", NULL, &sun);
 728         if (ACPI_SUCCESS(status)) {
 729                 dev->pnp.sun = (unsigned long)sun;
 730                 result = device_create_file(&dev->dev, &dev_attr_sun);
 731                 if (result)
 732                         goto end;
 733         } else {
 734                 dev->pnp.sun = (unsigned long)-1;
 735         }
 736
 737         if (acpi_has_method(dev->handle, "_STA")) {
 738                 result = device_create_file(&dev->dev, &dev_attr_status);
 739                 if (result)
 740                         goto end;
 741         }
 742
 743         /*
 744          * If device has _EJ0, 'eject' file is created that is used to trigger
 745          * hot-removal function from userland.
 746          */
 747         if (acpi_has_method(dev->handle, "_EJ0")) {
 748                 result = device_create_file(&dev->dev, &dev_attr_eject);
 749                 if (result)
 750                         return result;
 751         }
 752
 753         if (dev->flags.power_manageable) {
 754                 result = device_create_file(&dev->dev, &dev_attr_power_state);
 755                 if (result)
 756                         return result;
 757
 758                 if (dev->power.flags.power_resources)
 759                         result = device_create_file(&dev->dev,
 760                                                     &dev_attr_real_power_state);
 761         }
 762
 763 end:
 764         return result;
 765 }
 766
 767 static void acpi_device_remove_files(struct acpi_device *dev)
 768 {
 769         if (dev->flags.power_manageable) {
 770                 device_remove_file(&dev->dev, &dev_attr_power_state);
 771                 if (dev->power.flags.power_resources)
 772                         device_remove_file(&dev->dev,
 773                                            &dev_attr_real_power_state);
 774         }
 775
 776         /*
 777          * If device has _STR, remove 'description' file
 778          */
 779         if (acpi_has_method(dev->handle, "_STR")) {
 780                 kfree(dev->pnp.str_obj);
 781                 device_remove_file(&dev->dev, &dev_attr_description);
 782         }
 783         /*
 784          * If device has _EJ0, remove 'eject' file.
 785          */
 786         if (acpi_has_method(dev->handle, "_EJ0"))
 787                 device_remove_file(&dev->dev, &dev_attr_eject);
 788
 789         if (acpi_has_method(dev->handle, "_SUN"))
 790                 device_remove_file(&dev->dev, &dev_attr_sun);
 791
 792         if (dev->pnp.unique_id)
 793                 device_remove_file(&dev->dev, &dev_attr_uid);
 794         if (dev->pnp.type.bus_address)
 795                 device_remove_file(&dev->dev, &dev_attr_adr);
 796         device_remove_file(&dev->dev, &dev_attr_modalias);
 797         device_remove_file(&dev->dev, &dev_attr_hid);
 798         if (acpi_has_method(dev->handle, "_STA"))
 799                 device_remove_file(&dev->dev, &dev_attr_status);
 800         if (dev->handle)
 801                 device_remove_file(&dev->dev, &dev_attr_path);
 802 }
 803 /* --------------------------------------------------------------------------
 804                         ACPI Bus operations
 805    -------------------------------------------------------------------------- */
 806
 807 static const struct acpi_device_id *__acpi_match_device(
 808         struct acpi_device *device, const struct acpi_device_id *ids)
 809 {
 810         const struct acpi_device_id *id;
 811         struct acpi_hardware_id *hwid;
 812
 813         /*
 814          * If the device is not present, it is unnecessary to load device
 815          * driver for it.
 816          */
 817         if (!device->status.present)
 818                 return NULL;
 819
 820         for (id = ids; id->id[0]; id++)
 821                 list_for_each_entry(hwid, &device->pnp.ids, list)
 822                         if (!strcmp((char *) id->id, hwid->id))
 823                                 return id;
 824
 825         return NULL;
 826 }
 827
 828 /**
 829  * acpi_match_device - Match a struct device against a given list of ACPI IDs
 830  * @ids: Array of struct acpi_device_id object to match against.
 831  * @dev: The device structure to match.
 832  *
 833  * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
 834  * object for that handle and use that object to match against a given list of
 835  * device IDs.
 836  *
 837  * Return a pointer to the first matching ID on success or %NULL on failure.
 838  */
 839 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
 840                                                const struct device *dev)
 841 {
 842         struct acpi_device *adev;
 843         acpi_handle handle = ACPI_HANDLE(dev);
 844
 845         if (!ids || !handle || acpi_bus_get_device(handle, &adev))
 846                 return NULL;
 847
 848         return __acpi_match_device(adev, ids);
 849 }
 850 EXPORT_SYMBOL_GPL(acpi_match_device);
 851
 852 int acpi_match_device_ids(struct acpi_device *device,
 853                           const struct acpi_device_id *ids)
 854 {
 855         return __acpi_match_device(device, ids) ? 0 : -ENOENT;
 856 }
 857 EXPORT_SYMBOL(acpi_match_device_ids);
 858
 859 static void acpi_free_power_resources_lists(struct acpi_device *device)
 860 {
 861         int i;
 862
 863         if (device->wakeup.flags.valid)
 864                 acpi_power_resources_list_free(&device->wakeup.resources);
 865
 866         if (!device->flags.power_manageable)
 867                 return;
 868
 869         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 870                 struct acpi_device_power_state *ps = &device->power.states[i];
 871                 acpi_power_resources_list_free(&ps->resources);
 872         }
 873 }
 874
 875 static void acpi_device_release(struct device *dev)
 876 {
 877         struct acpi_device *acpi_dev = to_acpi_device(dev);
 878
 879         acpi_free_pnp_ids(&acpi_dev->pnp);
 880         acpi_free_power_resources_lists(acpi_dev);
 881         kfree(acpi_dev);
 882 }
 883
 884 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 885 {
 886         struct acpi_device *acpi_dev = to_acpi_device(dev);
 887         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 888
 889         return acpi_dev->flags.match_driver
 890                 && !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 891 }
 892
 893 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 894 {
 895         struct acpi_device *acpi_dev = to_acpi_device(dev);
 896         int len;
 897
 898         if (list_empty(&acpi_dev->pnp.ids))
 899                 return 0;
 900
 901         if (add_uevent_var(env, "MODALIAS="))
 902                 return -ENOMEM;
 903         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 904                               sizeof(env->buf) - env->buflen);
 905         if (len <= 0)
 906                 return len;
 907         env->buflen += len;
 908         return 0;
 909 }
 910
 911 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 912 {
 913         struct acpi_device *device = data;
 914
 915         device->driver->ops.notify(device, event);
 916 }
 917
 918 static acpi_status acpi_device_notify_fixed(void *data)
 919 {
 920         struct acpi_device *device = data;
 921
 922         /* Fixed hardware devices have no handles */
 923         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 924         return AE_OK;
 925 }
 926
 927 static int acpi_device_install_notify_handler(struct acpi_device *device)
 928 {
 929         acpi_status status;
 930
 931         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 932                 status =
 933                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 934                                                      acpi_device_notify_fixed,
 935                                                      device);
 936         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 937                 status =
 938                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 939                                                      acpi_device_notify_fixed,
 940                                                      device);
 941         else
 942                 status = acpi_install_notify_handler(device->handle,
 943                                                      ACPI_DEVICE_NOTIFY,
 944                                                      acpi_device_notify,
 945                                                      device);
 946
 947         if (ACPI_FAILURE(status))
 948                 return -EINVAL;
 949         return 0;
 950 }
 951
 952 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 953 {
 954         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 955                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 956                                                 acpi_device_notify_fixed);
 957         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 958                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 959                                                 acpi_device_notify_fixed);
 960         else
 961                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 962                                            acpi_device_notify);
 963 }
 964
 965 static int acpi_device_probe(struct device *dev)
 966 {
 967         struct acpi_device *acpi_dev = to_acpi_device(dev);
 968         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 969         int ret;
 970
 971         if (acpi_dev->handler)
 972                 return -EINVAL;
 973
 974         if (!acpi_drv->ops.add)
 975                 return -ENOSYS;
 976
 977         ret = acpi_drv->ops.add(acpi_dev);
 978         if (ret)
 979                 return ret;
 980
 981         acpi_dev->driver = acpi_drv;
 982         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 983                           "Driver [%s] successfully bound to device [%s]\n",
 984                           acpi_drv->name, acpi_dev->pnp.bus_id));
 985
 986         if (acpi_drv->ops.notify) {
 987                 ret = acpi_device_install_notify_handler(acpi_dev);
 988                 if (ret) {
 989                         if (acpi_drv->ops.remove)
 990                                 acpi_drv->ops.remove(acpi_dev);
 991
 992                         acpi_dev->driver = NULL;
 993                         acpi_dev->driver_data = NULL;
 994                         return ret;
 995                 }
 996         }
 997
 998         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
 999                           acpi_drv->name, acpi_dev->pnp.bus_id));
1000         get_device(dev);
1001         return 0;
1002 }
1003
1004 static int acpi_device_remove(struct device * dev)
1005 {
1006         struct acpi_device *acpi_dev = to_acpi_device(dev);
1007         struct acpi_driver *acpi_drv = acpi_dev->driver;
1008
1009         if (acpi_drv) {
1010                 if (acpi_drv->ops.notify)
1011                         acpi_device_remove_notify_handler(acpi_dev);
1012                 if (acpi_drv->ops.remove)
1013                         acpi_drv->ops.remove(acpi_dev);
1014         }
1015         acpi_dev->driver = NULL;
1016         acpi_dev->driver_data = NULL;
1017
1018         put_device(dev);
1019         return 0;
1020 }
1021
1022 struct bus_type acpi_bus_type = {
1023         .name           = "acpi",
1024         .match          = acpi_bus_match,
1025         .probe          = acpi_device_probe,
1026         .remove         = acpi_device_remove,
1027         .uevent         = acpi_device_uevent,
1028 };
1029
1030 static void acpi_device_del(struct acpi_device *device)
1031 {
1032         mutex_lock(&acpi_device_lock);
1033         if (device->parent)
1034                 list_del(&device->node);
1035
1036         list_del(&device->wakeup_list);
1037         mutex_unlock(&acpi_device_lock);
1038
1039         acpi_power_add_remove_device(device, false);
1040         acpi_device_remove_files(device);
1041         if (device->remove)
1042                 device->remove(device);
1043
1044         device_del(&device->dev);
1045 }
1046
1047 static LIST_HEAD(acpi_device_del_list);
1048 static DEFINE_MUTEX(acpi_device_del_lock);
1049
1050 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
1051 {
1052         for (;;) {
1053                 struct acpi_device *adev;
1054
1055                 mutex_lock(&acpi_device_del_lock);
1056
1057                 if (list_empty(&acpi_device_del_list)) {
1058                         mutex_unlock(&acpi_device_del_lock);
1059                         break;
1060                 }
1061                 adev = list_first_entry(&acpi_device_del_list,
1062                                         struct acpi_device, del_list);
1063                 list_del(&adev->del_list);
1064
1065                 mutex_unlock(&acpi_device_del_lock);
1066
1067                 acpi_device_del(adev);
1068                 /*
1069                  * Drop references to all power resources that might have been
1070                  * used by the device.
1071                  */
1072                 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
1073                 put_device(&adev->dev);
1074         }
1075 }
1076
1077 /**
1078  * acpi_scan_drop_device - Drop an ACPI device object.
1079  * @handle: Handle of an ACPI namespace node, not used.
1080  * @context: Address of the ACPI device object to drop.
1081  *
1082  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
1083  * namespace node the device object pointed to by @context is attached to.
1084  *
1085  * The unregistration is carried out asynchronously to avoid running
1086  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
1087  * ensure the correct ordering (the device objects must be unregistered in the
1088  * same order in which the corresponding namespace nodes are deleted).
1089  */
1090 static void acpi_scan_drop_device(acpi_handle handle, void *context)
1091 {
1092         static DECLARE_WORK(work, acpi_device_del_work_fn);
1093         struct acpi_device *adev = context;
1094
1095         mutex_lock(&acpi_device_del_lock);
1096
1097         /*
1098          * Use the ACPI hotplug workqueue which is ordered, so this work item
1099          * won't run after any hotplug work items submitted subsequently.  That
1100          * prevents attempts to register device objects identical to those being
1101          * deleted from happening concurrently (such attempts result from
1102          * hotplug events handled via the ACPI hotplug workqueue).  It also will
1103          * run after all of the work items submitted previosuly, which helps
1104          * those work items to ensure that they are not accessing stale device
1105          * objects.
1106          */
1107         if (list_empty(&acpi_device_del_list))
1108                 acpi_queue_hotplug_work(&work);
1109
1110         list_add_tail(&adev->del_list, &acpi_device_del_list);
1111         /* Make acpi_ns_validate_handle() return NULL for this handle. */
1112         adev->handle = INVALID_ACPI_HANDLE;
1113
1114         mutex_unlock(&acpi_device_del_lock);
1115 }
1116
1117 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
1118 {
1119         acpi_status status;
1120
1121         if (!device)
1122                 return -EINVAL;
1123
1124         status = acpi_get_data(handle, acpi_scan_drop_device, (void **)device);
1125         if (ACPI_FAILURE(status) || !*device) {
1126                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
1127                                   handle));
1128                 return -ENODEV;
1129         }
1130         return 0;
1131 }
1132 EXPORT_SYMBOL(acpi_bus_get_device);
1133
1134 int acpi_device_add(struct acpi_device *device,
1135                     void (*release)(struct device *))
1136 {
1137         int result;
1138         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
1139         int found = 0;
1140
1141         if (device->handle) {
1142                 acpi_status status;
1143
1144                 status = acpi_attach_data(device->handle, acpi_scan_drop_device,
1145                                           device);
1146                 if (ACPI_FAILURE(status)) {
1147                         acpi_handle_err(device->handle,
1148                                         "Unable to attach device data\n");
1149                         return -ENODEV;
1150                 }
1151         }
1152
1153         /*
1154          * Linkage
1155          * -------
1156          * Link this device to its parent and siblings.
1157          */
1158         INIT_LIST_HEAD(&device->children);
1159         INIT_LIST_HEAD(&device->node);
1160         INIT_LIST_HEAD(&device->wakeup_list);
1161         INIT_LIST_HEAD(&device->physical_node_list);
1162         INIT_LIST_HEAD(&device->del_list);
1163         mutex_init(&device->physical_node_lock);
1164
1165         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
1166         if (!new_bus_id) {
1167                 pr_err(PREFIX "Memory allocation error\n");
1168                 result = -ENOMEM;
1169                 goto err_detach;
1170         }
1171
1172         mutex_lock(&acpi_device_lock);
1173         /*
1174          * Find suitable bus_id and instance number in acpi_bus_id_list
1175          * If failed, create one and link it into acpi_bus_id_list
1176          */
1177         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
1178                 if (!strcmp(acpi_device_bus_id->bus_id,
1179                             acpi_device_hid(device))) {
1180                         acpi_device_bus_id->instance_no++;
1181                         found = 1;
1182                         kfree(new_bus_id);
1183                         break;
1184                 }
1185         }
1186         if (!found) {
1187                 acpi_device_bus_id = new_bus_id;
1188                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
1189                 acpi_device_bus_id->instance_no = 0;
1190                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
1191         }
1192         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
1193
1194         if (device->parent)
1195                 list_add_tail(&device->node, &device->parent->children);
1196
1197         if (device->wakeup.flags.valid)
1198                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
1199         mutex_unlock(&acpi_device_lock);
1200
1201         if (device->parent)
1202                 device->dev.parent = &device->parent->dev;
1203         device->dev.bus = &acpi_bus_type;
1204         device->dev.release = release;
1205         result = device_add(&device->dev);
1206         if (result) {
1207                 dev_err(&device->dev, "Error registering device\n");
1208                 goto err;
1209         }
1210
1211         result = acpi_device_setup_files(device);
1212         if (result)
1213                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
1214                        dev_name(&device->dev));
1215
1216         return 0;
1217
1218  err:
1219         mutex_lock(&acpi_device_lock);
1220         if (device->parent)
1221                 list_del(&device->node);
1222         list_del(&device->wakeup_list);
1223         mutex_unlock(&acpi_device_lock);
1224
1225  err_detach:
1226         acpi_detach_data(device->handle, acpi_scan_drop_device);
1227         return result;
1228 }
1229
1230 /* --------------------------------------------------------------------------
1231                                  Driver Management
1232    -------------------------------------------------------------------------- */
1233 /**
1234  * acpi_bus_register_driver - register a driver with the ACPI bus
1235  * @driver: driver being registered
1236  *
1237  * Registers a driver with the ACPI bus.  Searches the namespace for all
1238  * devices that match the driver's criteria and binds.  Returns zero for
1239  * success or a negative error status for failure.
1240  */
1241 int acpi_bus_register_driver(struct acpi_driver *driver)
1242 {
1243         int ret;
1244
1245         if (acpi_disabled)
1246                 return -ENODEV;
1247         driver->drv.name = driver->name;
1248         driver->drv.bus = &acpi_bus_type;
1249         driver->drv.owner = driver->owner;
1250
1251         ret = driver_register(&driver->drv);
1252         return ret;
1253 }
1254
1255 EXPORT_SYMBOL(acpi_bus_register_driver);
1256
1257 /**
1258  * acpi_bus_unregister_driver - unregisters a driver with the ACPI bus
1259  * @driver: driver to unregister
1260  *
1261  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
1262  * devices that match the driver's criteria and unbinds.
1263  */
1264 void acpi_bus_unregister_driver(struct acpi_driver *driver)
1265 {
1266         driver_unregister(&driver->drv);
1267 }
1268
1269 EXPORT_SYMBOL(acpi_bus_unregister_driver);
1270
1271 /* --------------------------------------------------------------------------
1272                                  Device Enumeration
1273    -------------------------------------------------------------------------- */
1274 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
1275 {
1276         struct acpi_device *device = NULL;
1277         acpi_status status;
1278
1279         /*
1280          * Fixed hardware devices do not appear in the namespace and do not
1281          * have handles, but we fabricate acpi_devices for them, so we have
1282          * to deal with them specially.
1283          */
1284         if (!handle)
1285                 return acpi_root;
1286
1287         do {
1288                 status = acpi_get_parent(handle, &handle);
1289                 if (ACPI_FAILURE(status))
1290                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
1291         } while (acpi_bus_get_device(handle, &device));
1292         return device;
1293 }
1294
1295 acpi_status
1296 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
1297 {
1298         acpi_status status;
1299         acpi_handle tmp;
1300         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
1301         union acpi_object *obj;
1302
1303         status = acpi_get_handle(handle, "_EJD", &tmp);
1304         if (ACPI_FAILURE(status))
1305                 return status;
1306
1307         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
1308         if (ACPI_SUCCESS(status)) {
1309                 obj = buffer.pointer;
1310                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
1311                                          ejd);
1312                 kfree(buffer.pointer);
1313         }
1314         return status;
1315 }
1316 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
1317
1318 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
1319                                         struct acpi_device_wakeup *wakeup)
1320 {
1321         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1322         union acpi_object *package = NULL;
1323         union acpi_object *element = NULL;
1324         acpi_status status;
1325         int err = -ENODATA;
1326
1327         if (!wakeup)
1328                 return -EINVAL;
1329
1330         INIT_LIST_HEAD(&wakeup->resources);
1331
1332         /* _PRW */
1333         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
1334         if (ACPI_FAILURE(status)) {
1335                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
1336                 return err;
1337         }
1338
1339         package = (union acpi_object *)buffer.pointer;
1340
1341         if (!package || package->package.count < 2)
1342                 goto out;
1343
1344         element = &(package->package.elements[0]);
1345         if (!element)
1346                 goto out;
1347
1348         if (element->type == ACPI_TYPE_PACKAGE) {
1349                 if ((element->package.count < 2) ||
1350                     (element->package.elements[0].type !=
1351                      ACPI_TYPE_LOCAL_REFERENCE)
1352                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
1353                         goto out;
1354
1355                 wakeup->gpe_device =
1356                     element->package.elements[0].reference.handle;
1357                 wakeup->gpe_number =
1358                     (u32) element->package.elements[1].integer.value;
1359         } else if (element->type == ACPI_TYPE_INTEGER) {
1360                 wakeup->gpe_device = NULL;
1361                 wakeup->gpe_number = element->integer.value;
1362         } else {
1363                 goto out;
1364         }
1365
1366         element = &(package->package.elements[1]);
1367         if (element->type != ACPI_TYPE_INTEGER)
1368                 goto out;
1369
1370         wakeup->sleep_state = element->integer.value;
1371
1372         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
1373         if (err)
1374                 goto out;
1375
1376         if (!list_empty(&wakeup->resources)) {
1377                 int sleep_state;
1378
1379                 err = acpi_power_wakeup_list_init(&wakeup->resources,
1380                                                   &sleep_state);
1381                 if (err) {
1382                         acpi_handle_warn(handle, "Retrieving current states "
1383                                          "of wakeup power resources failed\n");
1384                         acpi_power_resources_list_free(&wakeup->resources);
1385                         goto out;
1386                 }
1387                 if (sleep_state < wakeup->sleep_state) {
1388                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
1389                                          "(S%d) by S%d from power resources\n",
1390                                          (int)wakeup->sleep_state, sleep_state);
1391                         wakeup->sleep_state = sleep_state;
1392                 }
1393         }
1394         acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
1395
1396  out:
1397         kfree(buffer.pointer);
1398         return err;
1399 }
1400
1401 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
1402 {
1403         struct acpi_device_id button_device_ids[] = {
1404                 {"PNP0C0C", 0},
1405                 {"PNP0C0D", 0},
1406                 {"PNP0C0E", 0},
1407                 {"", 0},
1408         };
1409         acpi_status status;
1410         acpi_event_status event_status;
1411
1412         device->wakeup.flags.notifier_present = 0;
1413
1414         /* Power button, Lid switch always enable wakeup */
1415         if (!acpi_match_device_ids(device, button_device_ids)) {
1416                 device->wakeup.flags.run_wake = 1;
1417                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
1418                         /* Do not use Lid/sleep button for S5 wakeup */
1419                         if (device->wakeup.sleep_state == ACPI_STATE_S5)
1420                                 device->wakeup.sleep_state = ACPI_STATE_S4;
1421                 }
1422                 device_set_wakeup_capable(&device->dev, true);
1423                 return;
1424         }
1425
1426         status = acpi_get_gpe_status(device->wakeup.gpe_device,
1427                                         device->wakeup.gpe_number,
1428                                                 &event_status);
1429         if (status == AE_OK)
1430                 device->wakeup.flags.run_wake =
1431                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
1432 }
1433
1434 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1435 {
1436         int err;
1437
1438         /* Presence of _PRW indicates wake capable */
1439         if (!acpi_has_method(device->handle, "_PRW"))
1440                 return;
1441
1442         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
1443                                                            &device->wakeup);
1444         if (err) {
1445                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
1446                 return;
1447         }
1448
1449         device->wakeup.flags.valid = 1;
1450         device->wakeup.prepare_count = 0;
1451         acpi_bus_set_run_wake_flags(device);
1452         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
1453          * system for the ACPI device with the _PRW object.
1454          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
1455          * So it is necessary to call _DSW object first. Only when it is not
1456          * present will the _PSW object used.
1457          */
1458         err = acpi_device_sleep_wake(device, 0, 0, 0);
1459         if (err)
1460                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1461                                 "error in _DSW or _PSW evaluation\n"));
1462 }
1463
1464 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1465 {
1466         struct acpi_device_power_state *ps = &device->power.states[state];
1467         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1468         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1469         acpi_status status;
1470
1471         INIT_LIST_HEAD(&ps->resources);
1472
1473         /* Evaluate "_PRx" to get referenced power resources */
1474         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1475         if (ACPI_SUCCESS(status)) {
1476                 union acpi_object *package = buffer.pointer;
1477
1478                 if (buffer.length && package
1479                     && package->type == ACPI_TYPE_PACKAGE
1480                     && package->package.count) {
1481                         int err = acpi_extract_power_resources(package, 0,
1482                                                                &ps->resources);
1483                         if (!err)
1484                                 device->power.flags.power_resources = 1;
1485                 }
1486                 ACPI_FREE(buffer.pointer);
1487         }
1488
1489         /* Evaluate "_PSx" to see if we can do explicit sets */
1490         pathname[2] = 'S';
1491         if (acpi_has_method(device->handle, pathname))
1492                 ps->flags.explicit_set = 1;
1493
1494         /*
1495          * State is valid if there are means to put the device into it.
1496          * D3hot is only valid if _PR3 present.
1497          */
1498         if (!list_empty(&ps->resources)
1499             || (ps->flags.explicit_set && state < ACPI_STATE_D3_HOT)) {
1500                 ps->flags.valid = 1;
1501                 ps->flags.os_accessible = 1;
1502         }
1503
1504         ps->power = -1;         /* Unknown - driver assigned */
1505         ps->latency = -1;       /* Unknown - driver assigned */
1506 }
1507
1508 static void acpi_bus_get_power_flags(struct acpi_device *device)
1509 {
1510         u32 i;
1511
1512         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1513         if (!acpi_has_method(device->handle, "_PS0") &&
1514             !acpi_has_method(device->handle, "_PR0"))
1515                 return;
1516
1517         device->flags.power_manageable = 1;
1518
1519         /*
1520          * Power Management Flags
1521          */
1522         if (acpi_has_method(device->handle, "_PSC"))
1523                 device->power.flags.explicit_get = 1;
1524         if (acpi_has_method(device->handle, "_IRC"))
1525                 device->power.flags.inrush_current = 1;
1526
1527         /*
1528          * Enumerate supported power management states
1529          */
1530         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1531                 acpi_bus_init_power_state(device, i);
1532
1533         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1534
1535         /* Set defaults for D0 and D3 states (always valid) */
1536         device->power.states[ACPI_STATE_D0].flags.valid = 1;
1537         device->power.states[ACPI_STATE_D0].power = 100;
1538         device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
1539         device->power.states[ACPI_STATE_D3_COLD].power = 0;
1540
1541         /* Set D3cold's explicit_set flag if _PS3 exists. */
1542         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
1543                 device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
1544
1545         /* Presence of _PS3 or _PRx means we can put the device into D3 cold */
1546         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set ||
1547                         device->power.flags.power_resources)
1548                 device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
1549
1550         if (acpi_bus_init_power(device)) {
1551                 acpi_free_power_resources_lists(device);
1552                 device->flags.power_manageable = 0;
1553         }
1554 }
1555
1556 static void acpi_bus_get_flags(struct acpi_device *device)
1557 {
1558         /* Presence of _STA indicates 'dynamic_status' */
1559         if (acpi_has_method(device->handle, "_STA"))
1560                 device->flags.dynamic_status = 1;
1561
1562         /* Presence of _RMV indicates 'removable' */
1563         if (acpi_has_method(device->handle, "_RMV"))
1564                 device->flags.removable = 1;
1565
1566         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1567         if (acpi_has_method(device->handle, "_EJD") ||
1568             acpi_has_method(device->handle, "_EJ0"))
1569                 device->flags.ejectable = 1;
1570 }
1571
1572 static void acpi_device_get_busid(struct acpi_device *device)
1573 {
1574         char bus_id[5] = { '?', 0 };
1575         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1576         int i = 0;
1577
1578         /*
1579          * Bus ID
1580          * ------
1581          * The device's Bus ID is simply the object name.
1582          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1583          */
1584         if (ACPI_IS_ROOT_DEVICE(device)) {
1585                 strcpy(device->pnp.bus_id, "ACPI");
1586                 return;
1587         }
1588
1589         switch (device->device_type) {
1590         case ACPI_BUS_TYPE_POWER_BUTTON:
1591                 strcpy(device->pnp.bus_id, "PWRF");
1592                 break;
1593         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1594                 strcpy(device->pnp.bus_id, "SLPF");
1595                 break;
1596         default:
1597                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1598                 /* Clean up trailing underscores (if any) */
1599                 for (i = 3; i > 1; i--) {
1600                         if (bus_id[i] == '_')
1601                                 bus_id[i] = '\0';
1602                         else
1603                                 break;
1604                 }
1605                 strcpy(device->pnp.bus_id, bus_id);
1606                 break;
1607         }
1608 }
1609
1610 /*
1611  * acpi_ata_match - see if an acpi object is an ATA device
1612  *
1613  * If an acpi object has one of the ACPI ATA methods defined,
1614  * then we can safely call it an ATA device.
1615  */
1616 bool acpi_ata_match(acpi_handle handle)
1617 {
1618         return acpi_has_method(handle, "_GTF") ||
1619                acpi_has_method(handle, "_GTM") ||
1620                acpi_has_method(handle, "_STM") ||
1621                acpi_has_method(handle, "_SDD");
1622 }
1623
1624 /*
1625  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1626  *
1627  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1628  * then we can safely call it an ejectable drive bay
1629  */
1630 bool acpi_bay_match(acpi_handle handle)
1631 {
1632         acpi_handle phandle;
1633
1634         if (!acpi_has_method(handle, "_EJ0"))
1635                 return false;
1636         if (acpi_ata_match(handle))
1637                 return true;
1638         if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1639                 return false;
1640
1641         return acpi_ata_match(phandle);
1642 }
1643
1644 /*
1645  * acpi_dock_match - see if an acpi object has a _DCK method
1646  */
1647 bool acpi_dock_match(acpi_handle handle)
1648 {
1649         return acpi_has_method(handle, "_DCK");
1650 }
1651
1652 const char *acpi_device_hid(struct acpi_device *device)
1653 {
1654         struct acpi_hardware_id *hid;
1655
1656         if (list_empty(&device->pnp.ids))
1657                 return dummy_hid;
1658
1659         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1660         return hid->id;
1661 }
1662 EXPORT_SYMBOL(acpi_device_hid);
1663
1664 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1665 {
1666         struct acpi_hardware_id *id;
1667
1668         id = kmalloc(sizeof(*id), GFP_KERNEL);
1669         if (!id)
1670                 return;
1671
1672         id->id = kstrdup(dev_id, GFP_KERNEL);
1673         if (!id->id) {
1674                 kfree(id);
1675                 return;
1676         }
1677
1678         list_add_tail(&id->list, &pnp->ids);
1679         pnp->type.hardware_id = 1;
1680 }
1681
1682 /*
1683  * Old IBM workstations have a DSDT bug wherein the SMBus object
1684  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1685  * prefix.  Work around this.
1686  */
1687 static bool acpi_ibm_smbus_match(acpi_handle handle)
1688 {
1689         char node_name[ACPI_PATH_SEGMENT_LENGTH];
1690         struct acpi_buffer path = { sizeof(node_name), node_name };
1691
1692         if (!dmi_name_in_vendors("IBM"))
1693                 return false;
1694
1695         /* Look for SMBS object */
1696         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1697             strcmp("SMBS", path.pointer))
1698                 return false;
1699
1700         /* Does it have the necessary (but misnamed) methods? */
1701         if (acpi_has_method(handle, "SBI") &&
1702             acpi_has_method(handle, "SBR") &&
1703             acpi_has_method(handle, "SBW"))
1704                 return true;
1705
1706         return false;
1707 }
1708
1709 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1710                                 int device_type)
1711 {
1712         acpi_status status;
1713         struct acpi_device_info *info;
1714         struct acpi_pnp_device_id_list *cid_list;
1715         int i;
1716
1717         switch (device_type) {
1718         case ACPI_BUS_TYPE_DEVICE:
1719                 if (handle == ACPI_ROOT_OBJECT) {
1720                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1721                         break;
1722                 }
1723
1724                 status = acpi_get_object_info(handle, &info);
1725                 if (ACPI_FAILURE(status)) {
1726                         pr_err(PREFIX "%s: Error reading device info\n",
1727                                         __func__);
1728                         return;
1729                 }
1730
1731                 if (info->valid & ACPI_VALID_HID)
1732                         acpi_add_id(pnp, info->hardware_id.string);
1733                 if (info->valid & ACPI_VALID_CID) {
1734                         cid_list = &info->compatible_id_list;
1735                         for (i = 0; i < cid_list->count; i++)
1736                                 acpi_add_id(pnp, cid_list->ids[i].string);
1737                 }
1738                 if (info->valid & ACPI_VALID_ADR) {
1739                         pnp->bus_address = info->address;
1740                         pnp->type.bus_address = 1;
1741                 }
1742                 if (info->valid & ACPI_VALID_UID)
1743                         pnp->unique_id = kstrdup(info->unique_id.string,
1744                                                         GFP_KERNEL);
1745
1746                 kfree(info);
1747
1748                 /*
1749                  * Some devices don't reliably have _HIDs & _CIDs, so add
1750                  * synthetic HIDs to make sure drivers can find them.
1751                  */
1752                 if (acpi_is_video_device(handle))
1753                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1754                 else if (acpi_bay_match(handle))
1755                         acpi_add_id(pnp, ACPI_BAY_HID);
1756                 else if (acpi_dock_match(handle))
1757                         acpi_add_id(pnp, ACPI_DOCK_HID);
1758                 else if (acpi_ibm_smbus_match(handle))
1759                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1760                 else if (list_empty(&pnp->ids) && handle == ACPI_ROOT_OBJECT) {
1761                         acpi_add_id(pnp, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1762                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1763                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1764                 }
1765
1766                 break;
1767         case ACPI_BUS_TYPE_POWER:
1768                 acpi_add_id(pnp, ACPI_POWER_HID);
1769                 break;
1770         case ACPI_BUS_TYPE_PROCESSOR:
1771                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1772                 break;
1773         case ACPI_BUS_TYPE_THERMAL:
1774                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1775                 break;
1776         case ACPI_BUS_TYPE_POWER_BUTTON:
1777                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1778                 break;
1779         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1780                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1781                 break;
1782         }
1783 }
1784
1785 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1786 {
1787         struct acpi_hardware_id *id, *tmp;
1788
1789         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1790                 kfree(id->id);
1791                 kfree(id);
1792         }
1793         kfree(pnp->unique_id);
1794 }
1795
1796 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1797                              int type, unsigned long long sta)
1798 {
1799         INIT_LIST_HEAD(&device->pnp.ids);
1800         device->device_type = type;
1801         device->handle = handle;
1802         device->parent = acpi_bus_get_parent(handle);
1803         acpi_set_device_status(device, sta);
1804         acpi_device_get_busid(device);
1805         acpi_set_pnp_ids(handle, &device->pnp, type);
1806         acpi_bus_get_flags(device);
1807         device->flags.match_driver = false;
1808         device->flags.initialized = true;
1809         device->flags.visited = false;
1810         device_initialize(&device->dev);
1811         dev_set_uevent_suppress(&device->dev, true);
1812 }
1813
1814 void acpi_device_add_finalize(struct acpi_device *device)
1815 {
1816         dev_set_uevent_suppress(&device->dev, false);
1817         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1818 }
1819
1820 static int acpi_add_single_object(struct acpi_device **child,
1821                                   acpi_handle handle, int type,
1822                                   unsigned long long sta)
1823 {
1824         int result;
1825         struct acpi_device *device;
1826         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1827
1828         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1829         if (!device) {
1830                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1831                 return -ENOMEM;
1832         }
1833
1834         acpi_init_device_object(device, handle, type, sta);
1835         acpi_bus_get_power_flags(device);
1836         acpi_bus_get_wakeup_device_flags(device);
1837
1838         result = acpi_device_add(device, acpi_device_release);
1839         if (result) {
1840                 acpi_device_release(&device->dev);
1841                 return result;
1842         }
1843
1844         acpi_power_add_remove_device(device, true);
1845         acpi_device_add_finalize(device);
1846         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1847         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1848                 dev_name(&device->dev), (char *) buffer.pointer,
1849                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1850         kfree(buffer.pointer);
1851         *child = device;
1852         return 0;
1853 }
1854
1855 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1856                                     unsigned long long *sta)
1857 {
1858         acpi_status status;
1859         acpi_object_type acpi_type;
1860
1861         status = acpi_get_type(handle, &acpi_type);
1862         if (ACPI_FAILURE(status))
1863                 return -ENODEV;
1864
1865         switch (acpi_type) {
1866         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1867         case ACPI_TYPE_DEVICE:
1868                 *type = ACPI_BUS_TYPE_DEVICE;
1869                 status = acpi_bus_get_status_handle(handle, sta);
1870                 if (ACPI_FAILURE(status))
1871                         return -ENODEV;
1872                 break;
1873         case ACPI_TYPE_PROCESSOR:
1874                 *type = ACPI_BUS_TYPE_PROCESSOR;
1875                 status = acpi_bus_get_status_handle(handle, sta);
1876                 if (ACPI_FAILURE(status))
1877                         return -ENODEV;
1878                 break;
1879         case ACPI_TYPE_THERMAL:
1880                 *type = ACPI_BUS_TYPE_THERMAL;
1881                 *sta = ACPI_STA_DEFAULT;
1882                 break;
1883         case ACPI_TYPE_POWER:
1884                 *type = ACPI_BUS_TYPE_POWER;
1885                 *sta = ACPI_STA_DEFAULT;
1886                 break;
1887         default:
1888                 return -ENODEV;
1889         }
1890
1891         return 0;
1892 }
1893
1894 bool acpi_device_is_present(struct acpi_device *adev)
1895 {
1896         if (adev->status.present || adev->status.functional)
1897                 return true;
1898
1899         adev->flags.initialized = false;
1900         return false;
1901 }
1902
1903 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1904                                        char *idstr,
1905                                        const struct acpi_device_id **matchid)
1906 {
1907         const struct acpi_device_id *devid;
1908
1909         for (devid = handler->ids; devid->id[0]; devid++)
1910                 if (!strcmp((char *)devid->id, idstr)) {
1911                         if (matchid)
1912                                 *matchid = devid;
1913
1914                         return true;
1915                 }
1916
1917         return false;
1918 }
1919
1920 static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr,
1921                                         const struct acpi_device_id **matchid)
1922 {
1923         struct acpi_scan_handler *handler;
1924
1925         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1926                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1927                         return handler;
1928
1929         return NULL;
1930 }
1931
1932 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1933 {
1934         if (!!hotplug->enabled == !!val)
1935                 return;
1936
1937         mutex_lock(&acpi_scan_lock);
1938
1939         hotplug->enabled = val;
1940
1941         mutex_unlock(&acpi_scan_lock);
1942 }
1943
1944 static void acpi_scan_init_hotplug(acpi_handle handle, int type)
1945 {
1946         struct acpi_device_pnp pnp = {};
1947         struct acpi_hardware_id *hwid;
1948         struct acpi_scan_handler *handler;
1949
1950         INIT_LIST_HEAD(&pnp.ids);
1951         acpi_set_pnp_ids(handle, &pnp, type);
1952
1953         if (!pnp.type.hardware_id)
1954                 goto out;
1955
1956         /*
1957          * This relies on the fact that acpi_install_notify_handler() will not
1958          * install the same notify handler routine twice for the same handle.
1959          */
1960         list_for_each_entry(hwid, &pnp.ids, list) {
1961                 handler = acpi_scan_match_handler(hwid->id, NULL);
1962                 if (handler) {
1963                         acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
1964                                         acpi_hotplug_notify_cb, handler);
1965                         break;
1966                 }
1967         }
1968
1969 out:
1970         acpi_free_pnp_ids(&pnp);
1971 }
1972
1973 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1974                                       void *not_used, void **return_value)
1975 {
1976         struct acpi_device *device = NULL;
1977         int type;
1978         unsigned long long sta;
1979         int result;
1980
1981         acpi_bus_get_device(handle, &device);
1982         if (device)
1983                 goto out;
1984
1985         result = acpi_bus_type_and_status(handle, &type, &sta);
1986         if (result)
1987                 return AE_OK;
1988
1989         if (type == ACPI_BUS_TYPE_POWER) {
1990                 acpi_add_power_resource(handle);
1991                 return AE_OK;
1992         }
1993
1994         acpi_scan_init_hotplug(handle, type);
1995
1996         acpi_add_single_object(&device, handle, type, sta);
1997         if (!device)
1998                 return AE_CTRL_DEPTH;
1999
2000  out:
2001         if (!*return_value)
2002                 *return_value = device;
2003
2004         return AE_OK;
2005 }
2006
2007 static int acpi_scan_attach_handler(struct acpi_device *device)
2008 {
2009         struct acpi_hardware_id *hwid;
2010         int ret = 0;
2011
2012         list_for_each_entry(hwid, &device->pnp.ids, list) {
2013                 const struct acpi_device_id *devid;
2014                 struct acpi_scan_handler *handler;
2015
2016                 handler = acpi_scan_match_handler(hwid->id, &devid);
2017                 if (handler) {
2018                         ret = handler->attach(device, devid);
2019                         if (ret > 0) {
2020                                 device->handler = handler;
2021                                 break;
2022                         } else if (ret < 0) {
2023                                 break;
2024                         }
2025                 }
2026         }
2027         return ret;
2028 }
2029
2030 static void acpi_bus_attach(struct acpi_device *device)
2031 {
2032         struct acpi_device *child;
2033         int ret;
2034
2035         acpi_bus_get_status(device);
2036         /* Skip devices that are not present. */
2037         if (!acpi_device_is_present(device)) {
2038                 device->flags.visited = false;
2039                 return;
2040         }
2041         if (device->handler)
2042                 goto ok;
2043
2044         if (!device->flags.initialized) {
2045                 acpi_bus_update_power(device, NULL);
2046                 device->flags.initialized = true;
2047         }
2048         device->flags.visited = false;
2049         ret = acpi_scan_attach_handler(device);
2050         if (ret < 0)
2051                 return;
2052
2053         device->flags.match_driver = true;
2054         if (!ret) {
2055                 ret = device_attach(&device->dev);
2056                 if (ret < 0)
2057                         return;
2058         }
2059         device->flags.visited = true;
2060
2061  ok:
2062         list_for_each_entry(child, &device->children, node)
2063                 acpi_bus_attach(child);
2064 }
2065
2066 /**
2067  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2068  * @handle: Root of the namespace scope to scan.
2069  *
2070  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2071  * found devices.
2072  *
2073  * If no devices were found, -ENODEV is returned, but it does not mean that
2074  * there has been a real error.  There just have been no suitable ACPI objects
2075  * in the table trunk from which the kernel could create a device and add an
2076  * appropriate driver.
2077  *
2078  * Must be called under acpi_scan_lock.
2079  */
2080 int acpi_bus_scan(acpi_handle handle)
2081 {
2082         void *device = NULL;
2083
2084         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
2085                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2086                                     acpi_bus_check_add, NULL, NULL, &device);
2087
2088         if (device) {
2089                 acpi_bus_attach(device);
2090                 return 0;
2091         }
2092         return -ENODEV;
2093 }
2094 EXPORT_SYMBOL(acpi_bus_scan);
2095
2096 /**
2097  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2098  * @adev: Root of the ACPI namespace scope to walk.
2099  *
2100  * Must be called under acpi_scan_lock.
2101  */
2102 void acpi_bus_trim(struct acpi_device *adev)
2103 {
2104         struct acpi_scan_handler *handler = adev->handler;
2105         struct acpi_device *child;
2106
2107         list_for_each_entry_reverse(child, &adev->children, node)
2108                 acpi_bus_trim(child);
2109
2110         adev->flags.match_driver = false;
2111         if (handler) {
2112                 if (handler->detach)
2113                         handler->detach(adev);
2114
2115                 adev->handler = NULL;
2116         } else {
2117                 device_release_driver(&adev->dev);
2118         }
2119         /*
2120          * Most likely, the device is going away, so put it into D3cold before
2121          * that.
2122          */
2123         acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2124         adev->flags.initialized = false;
2125         adev->flags.visited = false;
2126 }
2127 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2128
2129 static int acpi_bus_scan_fixed(void)
2130 {
2131         int result = 0;
2132
2133         /*
2134          * Enumerate all fixed-feature devices.
2135          */
2136         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2137                 struct acpi_device *device = NULL;
2138
2139                 result = acpi_add_single_object(&device, NULL,
2140                                                 ACPI_BUS_TYPE_POWER_BUTTON,
2141                                                 ACPI_STA_DEFAULT);
2142                 if (result)
2143                         return result;
2144
2145                 device->flags.match_driver = true;
2146                 result = device_attach(&device->dev);
2147                 if (result < 0)
2148                         return result;
2149
2150                 device_init_wakeup(&device->dev, true);
2151         }
2152
2153         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2154                 struct acpi_device *device = NULL;
2155
2156                 result = acpi_add_single_object(&device, NULL,
2157                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2158                                                 ACPI_STA_DEFAULT);
2159                 if (result)
2160                         return result;
2161
2162                 device->flags.match_driver = true;
2163                 result = device_attach(&device->dev);
2164         }
2165
2166         return result < 0 ? result : 0;
2167 }
2168
2169 int __init acpi_scan_init(void)
2170 {
2171         int result;
2172
2173         result = bus_register(&acpi_bus_type);
2174         if (result) {
2175                 /* We don't want to quit even if we failed to add suspend/resume */
2176                 printk(KERN_ERR PREFIX "Could not register bus type\n");
2177         }
2178
2179         acpi_pci_root_init();
2180         acpi_pci_link_init();
2181         acpi_processor_init();
2182         acpi_platform_init();
2183         acpi_lpss_init();
2184         acpi_cmos_rtc_init();
2185         acpi_container_init();
2186         acpi_memory_hotplug_init();
2187         acpi_dock_init();
2188
2189         mutex_lock(&acpi_scan_lock);
2190         /*
2191          * Enumerate devices in the ACPI namespace.
2192          */
2193         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2194         if (result)
2195                 goto out;
2196
2197         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2198         if (result)
2199                 goto out;
2200
2201         result = acpi_bus_scan_fixed();
2202         if (result) {
2203                 acpi_detach_data(acpi_root->handle, acpi_scan_drop_device);
2204                 acpi_device_del(acpi_root);
2205                 put_device(&acpi_root->dev);
2206                 goto out;
2207         }
2208
2209         acpi_update_all_gpes();
2210
2211  out:
2212         mutex_unlock(&acpi_scan_lock);
2213         return result;
2214 }