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 static DEFINE_MUTEX(acpi_hp_context_lock);
  45
  46 struct acpi_device_bus_id{
  47         char bus_id[15];
  48         unsigned int instance_no;
  49         struct list_head node;
  50 };
  51
  52 void acpi_scan_lock_acquire(void)
  53 {
  54         mutex_lock(&acpi_scan_lock);
  55 }
  56 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
  57
  58 void acpi_scan_lock_release(void)
  59 {
  60         mutex_unlock(&acpi_scan_lock);
  61 }
  62 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
  63
  64 void acpi_lock_hp_context(void)
  65 {
  66         mutex_lock(&acpi_hp_context_lock);
  67 }
  68
  69 void acpi_unlock_hp_context(void)
  70 {
  71         mutex_unlock(&acpi_hp_context_lock);
  72 }
  73
  74 void acpi_initialize_hp_context(struct acpi_device *adev,
  75                                 struct acpi_hotplug_context *hp,
  76                                 int (*notify)(struct acpi_device *, u32),
  77                                 void (*uevent)(struct acpi_device *, u32))
  78 {
  79         acpi_lock_hp_context();
  80         hp->notify = notify;
  81         hp->uevent = uevent;
  82         acpi_set_hp_context(adev, hp);
  83         acpi_unlock_hp_context();
  84 }
  85 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
  86
  87 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
  88 {
  89         if (!handler)
  90                 return -EINVAL;
  91
  92         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
  93         return 0;
  94 }
  95
  96 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
  97                                        const char *hotplug_profile_name)
  98 {
  99         int error;
 100
 101         error = acpi_scan_add_handler(handler);
 102         if (error)
 103                 return error;
 104
 105         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
 106         return 0;
 107 }
 108
 109 /*
 110  * Creates hid/cid(s) string needed for modalias and uevent
 111  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
 112  * char *modalias: "acpi:IBM0001:ACPI0001"
 113  * Return: 0: no _HID and no _CID
 114  *         -EINVAL: output error
 115  *         -ENOMEM: output is truncated
 116 */
 117 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
 118                            int size)
 119 {
 120         int len;
 121         int count;
 122         struct acpi_hardware_id *id;
 123
 124         if (list_empty(&acpi_dev->pnp.ids))
 125                 return 0;
 126
 127         len = snprintf(modalias, size, "acpi:");
 128         size -= len;
 129
 130         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
 131                 count = snprintf(&modalias[len], size, "%s:", id->id);
 132                 if (count < 0)
 133                         return EINVAL;
 134                 if (count >= size)
 135                         return -ENOMEM;
 136                 len += count;
 137                 size -= count;
 138         }
 139
 140         modalias[len] = '\0';
 141         return len;
 142 }
 143
 144 /*
 145  * Creates uevent modalias field for ACPI enumerated devices.
 146  * Because the other buses does not support ACPI HIDs & CIDs.
 147  * e.g. for a device with hid:IBM0001 and cid:ACPI0001 you get:
 148  * "acpi:IBM0001:ACPI0001"
 149  */
 150 int acpi_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
 151 {
 152         struct acpi_device *acpi_dev;
 153         int len;
 154
 155         acpi_dev = ACPI_COMPANION(dev);
 156         if (!acpi_dev)
 157                 return -ENODEV;
 158
 159         /* Fall back to bus specific way of modalias exporting */
 160         if (list_empty(&acpi_dev->pnp.ids))
 161                 return -ENODEV;
 162
 163         if (add_uevent_var(env, "MODALIAS="))
 164                 return -ENOMEM;
 165         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 166                                 sizeof(env->buf) - env->buflen);
 167         if (len <= 0)
 168                 return len;
 169         env->buflen += len;
 170         return 0;
 171 }
 172 EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias);
 173
 174 /*
 175  * Creates modalias sysfs attribute for ACPI enumerated devices.
 176  * Because the other buses does not support ACPI HIDs & CIDs.
 177  * e.g. for a device with hid:IBM0001 and cid:ACPI0001 you get:
 178  * "acpi:IBM0001:ACPI0001"
 179  */
 180 int acpi_device_modalias(struct device *dev, char *buf, int size)
 181 {
 182         struct acpi_device *acpi_dev;
 183         int len;
 184
 185         acpi_dev = ACPI_COMPANION(dev);
 186         if (!acpi_dev)
 187                 return -ENODEV;
 188
 189         /* Fall back to bus specific way of modalias exporting */
 190         if (list_empty(&acpi_dev->pnp.ids))
 191                 return -ENODEV;
 192
 193         len = create_modalias(acpi_dev, buf, size -1);
 194         if (len <= 0)
 195                 return len;
 196         buf[len++] = '\n';
 197         return len;
 198 }
 199 EXPORT_SYMBOL_GPL(acpi_device_modalias);
 200
 201 static ssize_t
 202 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
 203         struct acpi_device *acpi_dev = to_acpi_device(dev);
 204         int len;
 205
 206         len = create_modalias(acpi_dev, buf, 1024);
 207         if (len <= 0)
 208                 return len;
 209         buf[len++] = '\n';
 210         return len;
 211 }
 212 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
 213
 214 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
 215 {
 216         struct acpi_device_physical_node *pn;
 217         bool offline = true;
 218
 219         mutex_lock(&adev->physical_node_lock);
 220
 221         list_for_each_entry(pn, &adev->physical_node_list, node)
 222                 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
 223                         if (uevent)
 224                                 kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
 225
 226                         offline = false;
 227                         break;
 228                 }
 229
 230         mutex_unlock(&adev->physical_node_lock);
 231         return offline;
 232 }
 233
 234 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
 235                                     void **ret_p)
 236 {
 237         struct acpi_device *device = NULL;
 238         struct acpi_device_physical_node *pn;
 239         bool second_pass = (bool)data;
 240         acpi_status status = AE_OK;
 241
 242         if (acpi_bus_get_device(handle, &device))
 243                 return AE_OK;
 244
 245         if (device->handler && !device->handler->hotplug.enabled) {
 246                 *ret_p = &device->dev;
 247                 return AE_SUPPORT;
 248         }
 249
 250         mutex_lock(&device->physical_node_lock);
 251
 252         list_for_each_entry(pn, &device->physical_node_list, node) {
 253                 int ret;
 254
 255                 if (second_pass) {
 256                         /* Skip devices offlined by the first pass. */
 257                         if (pn->put_online)
 258                                 continue;
 259                 } else {
 260                         pn->put_online = false;
 261                 }
 262                 ret = device_offline(pn->dev);
 263                 if (acpi_force_hot_remove)
 264                         continue;
 265
 266                 if (ret >= 0) {
 267                         pn->put_online = !ret;
 268                 } else {
 269                         *ret_p = pn->dev;
 270                         if (second_pass) {
 271                                 status = AE_ERROR;
 272                                 break;
 273                         }
 274                 }
 275         }
 276
 277         mutex_unlock(&device->physical_node_lock);
 278
 279         return status;
 280 }
 281
 282 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
 283                                    void **ret_p)
 284 {
 285         struct acpi_device *device = NULL;
 286         struct acpi_device_physical_node *pn;
 287
 288         if (acpi_bus_get_device(handle, &device))
 289                 return AE_OK;
 290
 291         mutex_lock(&device->physical_node_lock);
 292
 293         list_for_each_entry(pn, &device->physical_node_list, node)
 294                 if (pn->put_online) {
 295                         device_online(pn->dev);
 296                         pn->put_online = false;
 297                 }
 298
 299         mutex_unlock(&device->physical_node_lock);
 300
 301         return AE_OK;
 302 }
 303
 304 static int acpi_scan_try_to_offline(struct acpi_device *device)
 305 {
 306         acpi_handle handle = device->handle;
 307         struct device *errdev = NULL;
 308         acpi_status status;
 309
 310         /*
 311          * Carry out two passes here and ignore errors in the first pass,
 312          * because if the devices in question are memory blocks and
 313          * CONFIG_MEMCG is set, one of the blocks may hold data structures
 314          * that the other blocks depend on, but it is not known in advance which
 315          * block holds them.
 316          *
 317          * If the first pass is successful, the second one isn't needed, though.
 318          */
 319         status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 320                                      NULL, acpi_bus_offline, (void *)false,
 321                                      (void **)&errdev);
 322         if (status == AE_SUPPORT) {
 323                 dev_warn(errdev, "Offline disabled.\n");
 324                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 325                                     acpi_bus_online, NULL, NULL, NULL);
 326                 return -EPERM;
 327         }
 328         acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
 329         if (errdev) {
 330                 errdev = NULL;
 331                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 332                                     NULL, acpi_bus_offline, (void *)true,
 333                                     (void **)&errdev);
 334                 if (!errdev || acpi_force_hot_remove)
 335                         acpi_bus_offline(handle, 0, (void *)true,
 336                                          (void **)&errdev);
 337
 338                 if (errdev && !acpi_force_hot_remove) {
 339                         dev_warn(errdev, "Offline failed.\n");
 340                         acpi_bus_online(handle, 0, NULL, NULL);
 341                         acpi_walk_namespace(ACPI_TYPE_ANY, handle,
 342                                             ACPI_UINT32_MAX, acpi_bus_online,
 343                                             NULL, NULL, NULL);
 344                         return -EBUSY;
 345                 }
 346         }
 347         return 0;
 348 }
 349
 350 static int acpi_scan_hot_remove(struct acpi_device *device)
 351 {
 352         acpi_handle handle = device->handle;
 353         unsigned long long sta;
 354         acpi_status status;
 355
 356         if (device->handler && device->handler->hotplug.demand_offline
 357             && !acpi_force_hot_remove) {
 358                 if (!acpi_scan_is_offline(device, true))
 359                         return -EBUSY;
 360         } else {
 361                 int error = acpi_scan_try_to_offline(device);
 362                 if (error)
 363                         return error;
 364         }
 365
 366         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 367                 "Hot-removing device %s...\n", dev_name(&device->dev)));
 368
 369         acpi_bus_trim(device);
 370
 371         acpi_evaluate_lck(handle, 0);
 372         /*
 373          * TBD: _EJD support.
 374          */
 375         status = acpi_evaluate_ej0(handle);
 376         if (status == AE_NOT_FOUND)
 377                 return -ENODEV;
 378         else if (ACPI_FAILURE(status))
 379                 return -EIO;
 380
 381         /*
 382          * Verify if eject was indeed successful.  If not, log an error
 383          * message.  No need to call _OST since _EJ0 call was made OK.
 384          */
 385         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 386         if (ACPI_FAILURE(status)) {
 387                 acpi_handle_warn(handle,
 388                         "Status check after eject failed (0x%x)\n", status);
 389         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
 390                 acpi_handle_warn(handle,
 391                         "Eject incomplete - status 0x%llx\n", sta);
 392         }
 393
 394         return 0;
 395 }
 396
 397 static int acpi_scan_device_not_present(struct acpi_device *adev)
 398 {
 399         if (!acpi_device_enumerated(adev)) {
 400                 dev_warn(&adev->dev, "Still not present\n");
 401                 return -EALREADY;
 402         }
 403         acpi_bus_trim(adev);
 404         return 0;
 405 }
 406
 407 static int acpi_scan_device_check(struct acpi_device *adev)
 408 {
 409         int error;
 410
 411         acpi_bus_get_status(adev);
 412         if (adev->status.present || adev->status.functional) {
 413                 /*
 414                  * This function is only called for device objects for which
 415                  * matching scan handlers exist.  The only situation in which
 416                  * the scan handler is not attached to this device object yet
 417                  * is when the device has just appeared (either it wasn't
 418                  * present at all before or it was removed and then added
 419                  * again).
 420                  */
 421                 if (adev->handler) {
 422                         dev_warn(&adev->dev, "Already enumerated\n");
 423                         return -EALREADY;
 424                 }
 425                 error = acpi_bus_scan(adev->handle);
 426                 if (error) {
 427                         dev_warn(&adev->dev, "Namespace scan failure\n");
 428                         return error;
 429                 }
 430                 if (!adev->handler) {
 431                         dev_warn(&adev->dev, "Enumeration failure\n");
 432                         error = -ENODEV;
 433                 }
 434         } else {
 435                 error = acpi_scan_device_not_present(adev);
 436         }
 437         return error;
 438 }
 439
 440 static int acpi_scan_bus_check(struct acpi_device *adev)
 441 {
 442         struct acpi_scan_handler *handler = adev->handler;
 443         struct acpi_device *child;
 444         int error;
 445
 446         acpi_bus_get_status(adev);
 447         if (!(adev->status.present || adev->status.functional)) {
 448                 acpi_scan_device_not_present(adev);
 449                 return 0;
 450         }
 451         if (handler && handler->hotplug.scan_dependent)
 452                 return handler->hotplug.scan_dependent(adev);
 453
 454         error = acpi_bus_scan(adev->handle);
 455         if (error) {
 456                 dev_warn(&adev->dev, "Namespace scan failure\n");
 457                 return error;
 458         }
 459         list_for_each_entry(child, &adev->children, node) {
 460                 error = acpi_scan_bus_check(child);
 461                 if (error)
 462                         return error;
 463         }
 464         return 0;
 465 }
 466
 467 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
 468 {
 469         switch (type) {
 470         case ACPI_NOTIFY_BUS_CHECK:
 471                 return acpi_scan_bus_check(adev);
 472         case ACPI_NOTIFY_DEVICE_CHECK:
 473                 return acpi_scan_device_check(adev);
 474         case ACPI_NOTIFY_EJECT_REQUEST:
 475         case ACPI_OST_EC_OSPM_EJECT:
 476                 if (adev->handler && !adev->handler->hotplug.enabled) {
 477                         dev_info(&adev->dev, "Eject disabled\n");
 478                         return -EPERM;
 479                 }
 480                 acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
 481                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 482                 return acpi_scan_hot_remove(adev);
 483         }
 484         return -EINVAL;
 485 }
 486
 487 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
 488 {
 489         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 490         int error = -ENODEV;
 491
 492         lock_device_hotplug();
 493         mutex_lock(&acpi_scan_lock);
 494
 495         /*
 496          * The device object's ACPI handle cannot become invalid as long as we
 497          * are holding acpi_scan_lock, but it might have become invalid before
 498          * that lock was acquired.
 499          */
 500         if (adev->handle == INVALID_ACPI_HANDLE)
 501                 goto err_out;
 502
 503         if (adev->flags.is_dock_station) {
 504                 error = dock_notify(adev, src);
 505         } else if (adev->flags.hotplug_notify) {
 506                 error = acpi_generic_hotplug_event(adev, src);
 507                 if (error == -EPERM) {
 508                         ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 509                         goto err_out;
 510                 }
 511         } else {
 512                 int (*notify)(struct acpi_device *, u32);
 513
 514                 acpi_lock_hp_context();
 515                 notify = adev->hp ? adev->hp->notify : NULL;
 516                 acpi_unlock_hp_context();
 517                 /*
 518                  * There may be additional notify handlers for device objects
 519                  * without the .event() callback, so ignore them here.
 520                  */
 521                 if (notify)
 522                         error = notify(adev, src);
 523                 else
 524                         goto out;
 525         }
 526         if (!error)
 527                 ost_code = ACPI_OST_SC_SUCCESS;
 528
 529  err_out:
 530         acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
 531
 532  out:
 533         acpi_bus_put_acpi_device(adev);
 534         mutex_unlock(&acpi_scan_lock);
 535         unlock_device_hotplug();
 536 }
 537
 538 static ssize_t real_power_state_show(struct device *dev,
 539                                      struct device_attribute *attr, char *buf)
 540 {
 541         struct acpi_device *adev = to_acpi_device(dev);
 542         int state;
 543         int ret;
 544
 545         ret = acpi_device_get_power(adev, &state);
 546         if (ret)
 547                 return ret;
 548
 549         return sprintf(buf, "%s\n", acpi_power_state_string(state));
 550 }
 551
 552 static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL);
 553
 554 static ssize_t power_state_show(struct device *dev,
 555                                 struct device_attribute *attr, char *buf)
 556 {
 557         struct acpi_device *adev = to_acpi_device(dev);
 558
 559         return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
 560 }
 561
 562 static DEVICE_ATTR(power_state, 0444, power_state_show, NULL);
 563
 564 static ssize_t
 565 acpi_eject_store(struct device *d, struct device_attribute *attr,
 566                 const char *buf, size_t count)
 567 {
 568         struct acpi_device *acpi_device = to_acpi_device(d);
 569         acpi_object_type not_used;
 570         acpi_status status;
 571
 572         if (!count || buf[0] != '1')
 573                 return -EINVAL;
 574
 575         if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
 576             && !acpi_device->driver)
 577                 return -ENODEV;
 578
 579         status = acpi_get_type(acpi_device->handle, &not_used);
 580         if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
 581                 return -ENODEV;
 582
 583         get_device(&acpi_device->dev);
 584         status = acpi_hotplug_schedule(acpi_device, ACPI_OST_EC_OSPM_EJECT);
 585         if (ACPI_SUCCESS(status))
 586                 return count;
 587
 588         put_device(&acpi_device->dev);
 589         acpi_evaluate_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT,
 590                           ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
 591         return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
 592 }
 593
 594 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 595
 596 static ssize_t
 597 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 598         struct acpi_device *acpi_dev = to_acpi_device(dev);
 599
 600         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
 601 }
 602 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 603
 604 static ssize_t acpi_device_uid_show(struct device *dev,
 605                                     struct device_attribute *attr, char *buf)
 606 {
 607         struct acpi_device *acpi_dev = to_acpi_device(dev);
 608
 609         return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
 610 }
 611 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
 612
 613 static ssize_t acpi_device_adr_show(struct device *dev,
 614                                     struct device_attribute *attr, char *buf)
 615 {
 616         struct acpi_device *acpi_dev = to_acpi_device(dev);
 617
 618         return sprintf(buf, "0x%08x\n",
 619                        (unsigned int)(acpi_dev->pnp.bus_address));
 620 }
 621 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
 622
 623 static ssize_t
 624 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 625         struct acpi_device *acpi_dev = to_acpi_device(dev);
 626         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 627         int result;
 628
 629         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 630         if (result)
 631                 goto end;
 632
 633         result = sprintf(buf, "%s\n", (char*)path.pointer);
 634         kfree(path.pointer);
 635 end:
 636         return result;
 637 }
 638 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 639
 640 /* sysfs file that shows description text from the ACPI _STR method */
 641 static ssize_t description_show(struct device *dev,
 642                                 struct device_attribute *attr,
 643                                 char *buf) {
 644         struct acpi_device *acpi_dev = to_acpi_device(dev);
 645         int result;
 646
 647         if (acpi_dev->pnp.str_obj == NULL)
 648                 return 0;
 649
 650         /*
 651          * The _STR object contains a Unicode identifier for a device.
 652          * We need to convert to utf-8 so it can be displayed.
 653          */
 654         result = utf16s_to_utf8s(
 655                 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
 656                 acpi_dev->pnp.str_obj->buffer.length,
 657                 UTF16_LITTLE_ENDIAN, buf,
 658                 PAGE_SIZE);
 659
 660         buf[result++] = '\n';
 661
 662         return result;
 663 }
 664 static DEVICE_ATTR(description, 0444, description_show, NULL);
 665
 666 static ssize_t
 667 acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
 668                      char *buf) {
 669         struct acpi_device *acpi_dev = to_acpi_device(dev);
 670
 671         return sprintf(buf, "%lu\n", acpi_dev->pnp.sun);
 672 }
 673 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
 674
 675 static ssize_t status_show(struct device *dev, struct device_attribute *attr,
 676                                 char *buf) {
 677         struct acpi_device *acpi_dev = to_acpi_device(dev);
 678         acpi_status status;
 679         unsigned long long sta;
 680
 681         status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta);
 682         if (ACPI_FAILURE(status))
 683                 return -ENODEV;
 684
 685         return sprintf(buf, "%llu\n", sta);
 686 }
 687 static DEVICE_ATTR_RO(status);
 688
 689 static int acpi_device_setup_files(struct acpi_device *dev)
 690 {
 691         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 692         acpi_status status;
 693         unsigned long long sun;
 694         int result = 0;
 695
 696         /*
 697          * Devices gotten from FADT don't have a "path" attribute
 698          */
 699         if (dev->handle) {
 700                 result = device_create_file(&dev->dev, &dev_attr_path);
 701                 if (result)
 702                         goto end;
 703         }
 704
 705         if (!list_empty(&dev->pnp.ids)) {
 706                 result = device_create_file(&dev->dev, &dev_attr_hid);
 707                 if (result)
 708                         goto end;
 709
 710                 result = device_create_file(&dev->dev, &dev_attr_modalias);
 711                 if (result)
 712                         goto end;
 713         }
 714
 715         /*
 716          * If device has _STR, 'description' file is created
 717          */
 718         if (acpi_has_method(dev->handle, "_STR")) {
 719                 status = acpi_evaluate_object(dev->handle, "_STR",
 720                                         NULL, &buffer);
 721                 if (ACPI_FAILURE(status))
 722                         buffer.pointer = NULL;
 723                 dev->pnp.str_obj = buffer.pointer;
 724                 result = device_create_file(&dev->dev, &dev_attr_description);
 725                 if (result)
 726                         goto end;
 727         }
 728
 729         if (dev->pnp.type.bus_address)
 730                 result = device_create_file(&dev->dev, &dev_attr_adr);
 731         if (dev->pnp.unique_id)
 732                 result = device_create_file(&dev->dev, &dev_attr_uid);
 733
 734         status = acpi_evaluate_integer(dev->handle, "_SUN", NULL, &sun);
 735         if (ACPI_SUCCESS(status)) {
 736                 dev->pnp.sun = (unsigned long)sun;
 737                 result = device_create_file(&dev->dev, &dev_attr_sun);
 738                 if (result)
 739                         goto end;
 740         } else {
 741                 dev->pnp.sun = (unsigned long)-1;
 742         }
 743
 744         if (acpi_has_method(dev->handle, "_STA")) {
 745                 result = device_create_file(&dev->dev, &dev_attr_status);
 746                 if (result)
 747                         goto end;
 748         }
 749
 750         /*
 751          * If device has _EJ0, 'eject' file is created that is used to trigger
 752          * hot-removal function from userland.
 753          */
 754         if (acpi_has_method(dev->handle, "_EJ0")) {
 755                 result = device_create_file(&dev->dev, &dev_attr_eject);
 756                 if (result)
 757                         return result;
 758         }
 759
 760         if (dev->flags.power_manageable) {
 761                 result = device_create_file(&dev->dev, &dev_attr_power_state);
 762                 if (result)
 763                         return result;
 764
 765                 if (dev->power.flags.power_resources)
 766                         result = device_create_file(&dev->dev,
 767                                                     &dev_attr_real_power_state);
 768         }
 769
 770 end:
 771         return result;
 772 }
 773
 774 static void acpi_device_remove_files(struct acpi_device *dev)
 775 {
 776         if (dev->flags.power_manageable) {
 777                 device_remove_file(&dev->dev, &dev_attr_power_state);
 778                 if (dev->power.flags.power_resources)
 779                         device_remove_file(&dev->dev,
 780                                            &dev_attr_real_power_state);
 781         }
 782
 783         /*
 784          * If device has _STR, remove 'description' file
 785          */
 786         if (acpi_has_method(dev->handle, "_STR")) {
 787                 kfree(dev->pnp.str_obj);
 788                 device_remove_file(&dev->dev, &dev_attr_description);
 789         }
 790         /*
 791          * If device has _EJ0, remove 'eject' file.
 792          */
 793         if (acpi_has_method(dev->handle, "_EJ0"))
 794                 device_remove_file(&dev->dev, &dev_attr_eject);
 795
 796         if (acpi_has_method(dev->handle, "_SUN"))
 797                 device_remove_file(&dev->dev, &dev_attr_sun);
 798
 799         if (dev->pnp.unique_id)
 800                 device_remove_file(&dev->dev, &dev_attr_uid);
 801         if (dev->pnp.type.bus_address)
 802                 device_remove_file(&dev->dev, &dev_attr_adr);
 803         device_remove_file(&dev->dev, &dev_attr_modalias);
 804         device_remove_file(&dev->dev, &dev_attr_hid);
 805         if (acpi_has_method(dev->handle, "_STA"))
 806                 device_remove_file(&dev->dev, &dev_attr_status);
 807         if (dev->handle)
 808                 device_remove_file(&dev->dev, &dev_attr_path);
 809 }
 810 /* --------------------------------------------------------------------------
 811                         ACPI Bus operations
 812    -------------------------------------------------------------------------- */
 813
 814 static const struct acpi_device_id *__acpi_match_device(
 815         struct acpi_device *device, const struct acpi_device_id *ids)
 816 {
 817         const struct acpi_device_id *id;
 818         struct acpi_hardware_id *hwid;
 819
 820         /*
 821          * If the device is not present, it is unnecessary to load device
 822          * driver for it.
 823          */
 824         if (!device->status.present)
 825                 return NULL;
 826
 827         for (id = ids; id->id[0]; id++)
 828                 list_for_each_entry(hwid, &device->pnp.ids, list)
 829                         if (!strcmp((char *) id->id, hwid->id))
 830                                 return id;
 831
 832         return NULL;
 833 }
 834
 835 /**
 836  * acpi_match_device - Match a struct device against a given list of ACPI IDs
 837  * @ids: Array of struct acpi_device_id object to match against.
 838  * @dev: The device structure to match.
 839  *
 840  * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
 841  * object for that handle and use that object to match against a given list of
 842  * device IDs.
 843  *
 844  * Return a pointer to the first matching ID on success or %NULL on failure.
 845  */
 846 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
 847                                                const struct device *dev)
 848 {
 849         struct acpi_device *adev;
 850         acpi_handle handle = ACPI_HANDLE(dev);
 851
 852         if (!ids || !handle || acpi_bus_get_device(handle, &adev))
 853                 return NULL;
 854
 855         return __acpi_match_device(adev, ids);
 856 }
 857 EXPORT_SYMBOL_GPL(acpi_match_device);
 858
 859 int acpi_match_device_ids(struct acpi_device *device,
 860                           const struct acpi_device_id *ids)
 861 {
 862         return __acpi_match_device(device, ids) ? 0 : -ENOENT;
 863 }
 864 EXPORT_SYMBOL(acpi_match_device_ids);
 865
 866 static void acpi_free_power_resources_lists(struct acpi_device *device)
 867 {
 868         int i;
 869
 870         if (device->wakeup.flags.valid)
 871                 acpi_power_resources_list_free(&device->wakeup.resources);
 872
 873         if (!device->flags.power_manageable)
 874                 return;
 875
 876         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 877                 struct acpi_device_power_state *ps = &device->power.states[i];
 878                 acpi_power_resources_list_free(&ps->resources);
 879         }
 880 }
 881
 882 static void acpi_device_release(struct device *dev)
 883 {
 884         struct acpi_device *acpi_dev = to_acpi_device(dev);
 885
 886         acpi_free_pnp_ids(&acpi_dev->pnp);
 887         acpi_free_power_resources_lists(acpi_dev);
 888         kfree(acpi_dev);
 889 }
 890
 891 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 892 {
 893         struct acpi_device *acpi_dev = to_acpi_device(dev);
 894         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 895
 896         return acpi_dev->flags.match_driver
 897                 && !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 898 }
 899
 900 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 901 {
 902         struct acpi_device *acpi_dev = to_acpi_device(dev);
 903         int len;
 904
 905         if (list_empty(&acpi_dev->pnp.ids))
 906                 return 0;
 907
 908         if (add_uevent_var(env, "MODALIAS="))
 909                 return -ENOMEM;
 910         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 911                               sizeof(env->buf) - env->buflen);
 912         if (len <= 0)
 913                 return len;
 914         env->buflen += len;
 915         return 0;
 916 }
 917
 918 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 919 {
 920         struct acpi_device *device = data;
 921
 922         device->driver->ops.notify(device, event);
 923 }
 924
 925 static void acpi_device_notify_fixed(void *data)
 926 {
 927         struct acpi_device *device = data;
 928
 929         /* Fixed hardware devices have no handles */
 930         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 931 }
 932
 933 static acpi_status acpi_device_fixed_event(void *data)
 934 {
 935         acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_device_notify_fixed, data);
 936         return AE_OK;
 937 }
 938
 939 static int acpi_device_install_notify_handler(struct acpi_device *device)
 940 {
 941         acpi_status status;
 942
 943         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 944                 status =
 945                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 946                                                      acpi_device_fixed_event,
 947                                                      device);
 948         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 949                 status =
 950                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 951                                                      acpi_device_fixed_event,
 952                                                      device);
 953         else
 954                 status = acpi_install_notify_handler(device->handle,
 955                                                      ACPI_DEVICE_NOTIFY,
 956                                                      acpi_device_notify,
 957                                                      device);
 958
 959         if (ACPI_FAILURE(status))
 960                 return -EINVAL;
 961         return 0;
 962 }
 963
 964 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 965 {
 966         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 967                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 968                                                 acpi_device_fixed_event);
 969         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 970                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 971                                                 acpi_device_fixed_event);
 972         else
 973                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 974                                            acpi_device_notify);
 975 }
 976
 977 static int acpi_device_probe(struct device *dev)
 978 {
 979         struct acpi_device *acpi_dev = to_acpi_device(dev);
 980         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 981         int ret;
 982
 983         if (acpi_dev->handler && !acpi_is_pnp_device(acpi_dev))
 984                 return -EINVAL;
 985
 986         if (!acpi_drv->ops.add)
 987                 return -ENOSYS;
 988
 989         ret = acpi_drv->ops.add(acpi_dev);
 990         if (ret)
 991                 return ret;
 992
 993         acpi_dev->driver = acpi_drv;
 994         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 995                           "Driver [%s] successfully bound to device [%s]\n",
 996                           acpi_drv->name, acpi_dev->pnp.bus_id));
 997
 998         if (acpi_drv->ops.notify) {
 999                 ret = acpi_device_install_notify_handler(acpi_dev);
1000                 if (ret) {
1001                         if (acpi_drv->ops.remove)
1002                                 acpi_drv->ops.remove(acpi_dev);
1003
1004                         acpi_dev->driver = NULL;
1005                         acpi_dev->driver_data = NULL;
1006                         return ret;
1007                 }
1008         }
1009
1010         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
1011                           acpi_drv->name, acpi_dev->pnp.bus_id));
1012         get_device(dev);
1013         return 0;
1014 }
1015
1016 static int acpi_device_remove(struct device * dev)
1017 {
1018         struct acpi_device *acpi_dev = to_acpi_device(dev);
1019         struct acpi_driver *acpi_drv = acpi_dev->driver;
1020
1021         if (acpi_drv) {
1022                 if (acpi_drv->ops.notify)
1023                         acpi_device_remove_notify_handler(acpi_dev);
1024                 if (acpi_drv->ops.remove)
1025                         acpi_drv->ops.remove(acpi_dev);
1026         }
1027         acpi_dev->driver = NULL;
1028         acpi_dev->driver_data = NULL;
1029
1030         put_device(dev);
1031         return 0;
1032 }
1033
1034 struct bus_type acpi_bus_type = {
1035         .name           = "acpi",
1036         .match          = acpi_bus_match,
1037         .probe          = acpi_device_probe,
1038         .remove         = acpi_device_remove,
1039         .uevent         = acpi_device_uevent,
1040 };
1041
1042 static void acpi_device_del(struct acpi_device *device)
1043 {
1044         mutex_lock(&acpi_device_lock);
1045         if (device->parent)
1046                 list_del(&device->node);
1047
1048         list_del(&device->wakeup_list);
1049         mutex_unlock(&acpi_device_lock);
1050
1051         acpi_power_add_remove_device(device, false);
1052         acpi_device_remove_files(device);
1053         if (device->remove)
1054                 device->remove(device);
1055
1056         device_del(&device->dev);
1057 }
1058
1059 static LIST_HEAD(acpi_device_del_list);
1060 static DEFINE_MUTEX(acpi_device_del_lock);
1061
1062 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
1063 {
1064         for (;;) {
1065                 struct acpi_device *adev;
1066
1067                 mutex_lock(&acpi_device_del_lock);
1068
1069                 if (list_empty(&acpi_device_del_list)) {
1070                         mutex_unlock(&acpi_device_del_lock);
1071                         break;
1072                 }
1073                 adev = list_first_entry(&acpi_device_del_list,
1074                                         struct acpi_device, del_list);
1075                 list_del(&adev->del_list);
1076
1077                 mutex_unlock(&acpi_device_del_lock);
1078
1079                 acpi_device_del(adev);
1080                 /*
1081                  * Drop references to all power resources that might have been
1082                  * used by the device.
1083                  */
1084                 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
1085                 put_device(&adev->dev);
1086         }
1087 }
1088
1089 /**
1090  * acpi_scan_drop_device - Drop an ACPI device object.
1091  * @handle: Handle of an ACPI namespace node, not used.
1092  * @context: Address of the ACPI device object to drop.
1093  *
1094  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
1095  * namespace node the device object pointed to by @context is attached to.
1096  *
1097  * The unregistration is carried out asynchronously to avoid running
1098  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
1099  * ensure the correct ordering (the device objects must be unregistered in the
1100  * same order in which the corresponding namespace nodes are deleted).
1101  */
1102 static void acpi_scan_drop_device(acpi_handle handle, void *context)
1103 {
1104         static DECLARE_WORK(work, acpi_device_del_work_fn);
1105         struct acpi_device *adev = context;
1106
1107         mutex_lock(&acpi_device_del_lock);
1108
1109         /*
1110          * Use the ACPI hotplug workqueue which is ordered, so this work item
1111          * won't run after any hotplug work items submitted subsequently.  That
1112          * prevents attempts to register device objects identical to those being
1113          * deleted from happening concurrently (such attempts result from
1114          * hotplug events handled via the ACPI hotplug workqueue).  It also will
1115          * run after all of the work items submitted previosuly, which helps
1116          * those work items to ensure that they are not accessing stale device
1117          * objects.
1118          */
1119         if (list_empty(&acpi_device_del_list))
1120                 acpi_queue_hotplug_work(&work);
1121
1122         list_add_tail(&adev->del_list, &acpi_device_del_list);
1123         /* Make acpi_ns_validate_handle() return NULL for this handle. */
1124         adev->handle = INVALID_ACPI_HANDLE;
1125
1126         mutex_unlock(&acpi_device_del_lock);
1127 }
1128
1129 static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
1130                                 void (*callback)(void *))
1131 {
1132         acpi_status status;
1133
1134         if (!device)
1135                 return -EINVAL;
1136
1137         status = acpi_get_data_full(handle, acpi_scan_drop_device,
1138                                     (void **)device, callback);
1139         if (ACPI_FAILURE(status) || !*device) {
1140                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
1141                                   handle));
1142                 return -ENODEV;
1143         }
1144         return 0;
1145 }
1146
1147 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
1148 {
1149         return acpi_get_device_data(handle, device, NULL);
1150 }
1151 EXPORT_SYMBOL(acpi_bus_get_device);
1152
1153 static void get_acpi_device(void *dev)
1154 {
1155         if (dev)
1156                 get_device(&((struct acpi_device *)dev)->dev);
1157 }
1158
1159 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
1160 {
1161         struct acpi_device *adev = NULL;
1162
1163         acpi_get_device_data(handle, &adev, get_acpi_device);
1164         return adev;
1165 }
1166
1167 void acpi_bus_put_acpi_device(struct acpi_device *adev)
1168 {
1169         put_device(&adev->dev);
1170 }
1171
1172 int acpi_device_add(struct acpi_device *device,
1173                     void (*release)(struct device *))
1174 {
1175         int result;
1176         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
1177         int found = 0;
1178
1179         if (device->handle) {
1180                 acpi_status status;
1181
1182                 status = acpi_attach_data(device->handle, acpi_scan_drop_device,
1183                                           device);
1184                 if (ACPI_FAILURE(status)) {
1185                         acpi_handle_err(device->handle,
1186                                         "Unable to attach device data\n");
1187                         return -ENODEV;
1188                 }
1189         }
1190
1191         /*
1192          * Linkage
1193          * -------
1194          * Link this device to its parent and siblings.
1195          */
1196         INIT_LIST_HEAD(&device->children);
1197         INIT_LIST_HEAD(&device->node);
1198         INIT_LIST_HEAD(&device->wakeup_list);
1199         INIT_LIST_HEAD(&device->physical_node_list);
1200         INIT_LIST_HEAD(&device->del_list);
1201         mutex_init(&device->physical_node_lock);
1202
1203         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
1204         if (!new_bus_id) {
1205                 pr_err(PREFIX "Memory allocation error\n");
1206                 result = -ENOMEM;
1207                 goto err_detach;
1208         }
1209
1210         mutex_lock(&acpi_device_lock);
1211         /*
1212          * Find suitable bus_id and instance number in acpi_bus_id_list
1213          * If failed, create one and link it into acpi_bus_id_list
1214          */
1215         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
1216                 if (!strcmp(acpi_device_bus_id->bus_id,
1217                             acpi_device_hid(device))) {
1218                         acpi_device_bus_id->instance_no++;
1219                         found = 1;
1220                         kfree(new_bus_id);
1221                         break;
1222                 }
1223         }
1224         if (!found) {
1225                 acpi_device_bus_id = new_bus_id;
1226                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
1227                 acpi_device_bus_id->instance_no = 0;
1228                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
1229         }
1230         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
1231
1232         if (device->parent)
1233                 list_add_tail(&device->node, &device->parent->children);
1234
1235         if (device->wakeup.flags.valid)
1236                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
1237         mutex_unlock(&acpi_device_lock);
1238
1239         if (device->parent)
1240                 device->dev.parent = &device->parent->dev;
1241         device->dev.bus = &acpi_bus_type;
1242         device->dev.release = release;
1243         result = device_add(&device->dev);
1244         if (result) {
1245                 dev_err(&device->dev, "Error registering device\n");
1246                 goto err;
1247         }
1248
1249         result = acpi_device_setup_files(device);
1250         if (result)
1251                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
1252                        dev_name(&device->dev));
1253
1254         return 0;
1255
1256  err:
1257         mutex_lock(&acpi_device_lock);
1258         if (device->parent)
1259                 list_del(&device->node);
1260         list_del(&device->wakeup_list);
1261         mutex_unlock(&acpi_device_lock);
1262
1263  err_detach:
1264         acpi_detach_data(device->handle, acpi_scan_drop_device);
1265         return result;
1266 }
1267
1268 /* --------------------------------------------------------------------------
1269                                  Driver Management
1270    -------------------------------------------------------------------------- */
1271 /**
1272  * acpi_bus_register_driver - register a driver with the ACPI bus
1273  * @driver: driver being registered
1274  *
1275  * Registers a driver with the ACPI bus.  Searches the namespace for all
1276  * devices that match the driver's criteria and binds.  Returns zero for
1277  * success or a negative error status for failure.
1278  */
1279 int acpi_bus_register_driver(struct acpi_driver *driver)
1280 {
1281         int ret;
1282
1283         if (acpi_disabled)
1284                 return -ENODEV;
1285         driver->drv.name = driver->name;
1286         driver->drv.bus = &acpi_bus_type;
1287         driver->drv.owner = driver->owner;
1288
1289         ret = driver_register(&driver->drv);
1290         return ret;
1291 }
1292
1293 EXPORT_SYMBOL(acpi_bus_register_driver);
1294
1295 /**
1296  * acpi_bus_unregister_driver - unregisters a driver with the ACPI bus
1297  * @driver: driver to unregister
1298  *
1299  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
1300  * devices that match the driver's criteria and unbinds.
1301  */
1302 void acpi_bus_unregister_driver(struct acpi_driver *driver)
1303 {
1304         driver_unregister(&driver->drv);
1305 }
1306
1307 EXPORT_SYMBOL(acpi_bus_unregister_driver);
1308
1309 /* --------------------------------------------------------------------------
1310                                  Device Enumeration
1311    -------------------------------------------------------------------------- */
1312 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
1313 {
1314         struct acpi_device *device = NULL;
1315         acpi_status status;
1316
1317         /*
1318          * Fixed hardware devices do not appear in the namespace and do not
1319          * have handles, but we fabricate acpi_devices for them, so we have
1320          * to deal with them specially.
1321          */
1322         if (!handle)
1323                 return acpi_root;
1324
1325         do {
1326                 status = acpi_get_parent(handle, &handle);
1327                 if (ACPI_FAILURE(status))
1328                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
1329         } while (acpi_bus_get_device(handle, &device));
1330         return device;
1331 }
1332
1333 acpi_status
1334 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
1335 {
1336         acpi_status status;
1337         acpi_handle tmp;
1338         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
1339         union acpi_object *obj;
1340
1341         status = acpi_get_handle(handle, "_EJD", &tmp);
1342         if (ACPI_FAILURE(status))
1343                 return status;
1344
1345         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
1346         if (ACPI_SUCCESS(status)) {
1347                 obj = buffer.pointer;
1348                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
1349                                          ejd);
1350                 kfree(buffer.pointer);
1351         }
1352         return status;
1353 }
1354 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
1355
1356 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
1357                                         struct acpi_device_wakeup *wakeup)
1358 {
1359         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1360         union acpi_object *package = NULL;
1361         union acpi_object *element = NULL;
1362         acpi_status status;
1363         int err = -ENODATA;
1364
1365         if (!wakeup)
1366                 return -EINVAL;
1367
1368         INIT_LIST_HEAD(&wakeup->resources);
1369
1370         /* _PRW */
1371         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
1372         if (ACPI_FAILURE(status)) {
1373                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
1374                 return err;
1375         }
1376
1377         package = (union acpi_object *)buffer.pointer;
1378
1379         if (!package || package->package.count < 2)
1380                 goto out;
1381
1382         element = &(package->package.elements[0]);
1383         if (!element)
1384                 goto out;
1385
1386         if (element->type == ACPI_TYPE_PACKAGE) {
1387                 if ((element->package.count < 2) ||
1388                     (element->package.elements[0].type !=
1389                      ACPI_TYPE_LOCAL_REFERENCE)
1390                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
1391                         goto out;
1392
1393                 wakeup->gpe_device =
1394                     element->package.elements[0].reference.handle;
1395                 wakeup->gpe_number =
1396                     (u32) element->package.elements[1].integer.value;
1397         } else if (element->type == ACPI_TYPE_INTEGER) {
1398                 wakeup->gpe_device = NULL;
1399                 wakeup->gpe_number = element->integer.value;
1400         } else {
1401                 goto out;
1402         }
1403
1404         element = &(package->package.elements[1]);
1405         if (element->type != ACPI_TYPE_INTEGER)
1406                 goto out;
1407
1408         wakeup->sleep_state = element->integer.value;
1409
1410         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
1411         if (err)
1412                 goto out;
1413
1414         if (!list_empty(&wakeup->resources)) {
1415                 int sleep_state;
1416
1417                 err = acpi_power_wakeup_list_init(&wakeup->resources,
1418                                                   &sleep_state);
1419                 if (err) {
1420                         acpi_handle_warn(handle, "Retrieving current states "
1421                                          "of wakeup power resources failed\n");
1422                         acpi_power_resources_list_free(&wakeup->resources);
1423                         goto out;
1424                 }
1425                 if (sleep_state < wakeup->sleep_state) {
1426                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
1427                                          "(S%d) by S%d from power resources\n",
1428                                          (int)wakeup->sleep_state, sleep_state);
1429                         wakeup->sleep_state = sleep_state;
1430                 }
1431         }
1432
1433  out:
1434         kfree(buffer.pointer);
1435         return err;
1436 }
1437
1438 static void acpi_wakeup_gpe_init(struct acpi_device *device)
1439 {
1440         struct acpi_device_id button_device_ids[] = {
1441                 {"PNP0C0C", 0},
1442                 {"PNP0C0D", 0},
1443                 {"PNP0C0E", 0},
1444                 {"", 0},
1445         };
1446         struct acpi_device_wakeup *wakeup = &device->wakeup;
1447         acpi_status status;
1448         acpi_event_status event_status;
1449
1450         wakeup->flags.notifier_present = 0;
1451
1452         /* Power button, Lid switch always enable wakeup */
1453         if (!acpi_match_device_ids(device, button_device_ids)) {
1454                 wakeup->flags.run_wake = 1;
1455                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
1456                         /* Do not use Lid/sleep button for S5 wakeup */
1457                         if (wakeup->sleep_state == ACPI_STATE_S5)
1458                                 wakeup->sleep_state = ACPI_STATE_S4;
1459                 }
1460                 acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
1461                 device_set_wakeup_capable(&device->dev, true);
1462                 return;
1463         }
1464
1465         acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
1466                                 wakeup->gpe_number);
1467         status = acpi_get_gpe_status(wakeup->gpe_device, wakeup->gpe_number,
1468                                      &event_status);
1469         if (ACPI_FAILURE(status))
1470                 return;
1471
1472         wakeup->flags.run_wake = !!(event_status & ACPI_EVENT_FLAG_HANDLE);
1473 }
1474
1475 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1476 {
1477         int err;
1478
1479         /* Presence of _PRW indicates wake capable */
1480         if (!acpi_has_method(device->handle, "_PRW"))
1481                 return;
1482
1483         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
1484                                                            &device->wakeup);
1485         if (err) {
1486                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
1487                 return;
1488         }
1489
1490         device->wakeup.flags.valid = 1;
1491         device->wakeup.prepare_count = 0;
1492         acpi_wakeup_gpe_init(device);
1493         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
1494          * system for the ACPI device with the _PRW object.
1495          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
1496          * So it is necessary to call _DSW object first. Only when it is not
1497          * present will the _PSW object used.
1498          */
1499         err = acpi_device_sleep_wake(device, 0, 0, 0);
1500         if (err)
1501                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1502                                 "error in _DSW or _PSW evaluation\n"));
1503 }
1504
1505 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1506 {
1507         struct acpi_device_power_state *ps = &device->power.states[state];
1508         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1509         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1510         acpi_status status;
1511
1512         INIT_LIST_HEAD(&ps->resources);
1513
1514         /* Evaluate "_PRx" to get referenced power resources */
1515         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1516         if (ACPI_SUCCESS(status)) {
1517                 union acpi_object *package = buffer.pointer;
1518
1519                 if (buffer.length && package
1520                     && package->type == ACPI_TYPE_PACKAGE
1521                     && package->package.count) {
1522                         int err = acpi_extract_power_resources(package, 0,
1523                                                                &ps->resources);
1524                         if (!err)
1525                                 device->power.flags.power_resources = 1;
1526                 }
1527                 ACPI_FREE(buffer.pointer);
1528         }
1529
1530         /* Evaluate "_PSx" to see if we can do explicit sets */
1531         pathname[2] = 'S';
1532         if (acpi_has_method(device->handle, pathname))
1533                 ps->flags.explicit_set = 1;
1534
1535         /*
1536          * State is valid if there are means to put the device into it.
1537          * D3hot is only valid if _PR3 present.
1538          */
1539         if (!list_empty(&ps->resources)
1540             || (ps->flags.explicit_set && state < ACPI_STATE_D3_HOT)) {
1541                 ps->flags.valid = 1;
1542                 ps->flags.os_accessible = 1;
1543         }
1544
1545         ps->power = -1;         /* Unknown - driver assigned */
1546         ps->latency = -1;       /* Unknown - driver assigned */
1547 }
1548
1549 static void acpi_bus_get_power_flags(struct acpi_device *device)
1550 {
1551         u32 i;
1552
1553         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1554         if (!acpi_has_method(device->handle, "_PS0") &&
1555             !acpi_has_method(device->handle, "_PR0"))
1556                 return;
1557
1558         device->flags.power_manageable = 1;
1559
1560         /*
1561          * Power Management Flags
1562          */
1563         if (acpi_has_method(device->handle, "_PSC"))
1564                 device->power.flags.explicit_get = 1;
1565
1566         if (acpi_has_method(device->handle, "_IRC"))
1567                 device->power.flags.inrush_current = 1;
1568
1569         if (acpi_has_method(device->handle, "_DSW"))
1570                 device->power.flags.dsw_present = 1;
1571
1572         /*
1573          * Enumerate supported power management states
1574          */
1575         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1576                 acpi_bus_init_power_state(device, i);
1577
1578         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1579
1580         /* Set defaults for D0 and D3 states (always valid) */
1581         device->power.states[ACPI_STATE_D0].flags.valid = 1;
1582         device->power.states[ACPI_STATE_D0].power = 100;
1583         device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
1584         device->power.states[ACPI_STATE_D3_COLD].power = 0;
1585
1586         /* Set D3cold's explicit_set flag if _PS3 exists. */
1587         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
1588                 device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
1589
1590         /* Presence of _PS3 or _PRx means we can put the device into D3 cold */
1591         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set ||
1592                         device->power.flags.power_resources)
1593                 device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
1594
1595         if (acpi_bus_init_power(device)) {
1596                 acpi_free_power_resources_lists(device);
1597                 device->flags.power_manageable = 0;
1598         }
1599 }
1600
1601 static void acpi_bus_get_flags(struct acpi_device *device)
1602 {
1603         /* Presence of _STA indicates 'dynamic_status' */
1604         if (acpi_has_method(device->handle, "_STA"))
1605                 device->flags.dynamic_status = 1;
1606
1607         /* Presence of _RMV indicates 'removable' */
1608         if (acpi_has_method(device->handle, "_RMV"))
1609                 device->flags.removable = 1;
1610
1611         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1612         if (acpi_has_method(device->handle, "_EJD") ||
1613             acpi_has_method(device->handle, "_EJ0"))
1614                 device->flags.ejectable = 1;
1615 }
1616
1617 static void acpi_device_get_busid(struct acpi_device *device)
1618 {
1619         char bus_id[5] = { '?', 0 };
1620         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1621         int i = 0;
1622
1623         /*
1624          * Bus ID
1625          * ------
1626          * The device's Bus ID is simply the object name.
1627          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1628          */
1629         if (ACPI_IS_ROOT_DEVICE(device)) {
1630                 strcpy(device->pnp.bus_id, "ACPI");
1631                 return;
1632         }
1633
1634         switch (device->device_type) {
1635         case ACPI_BUS_TYPE_POWER_BUTTON:
1636                 strcpy(device->pnp.bus_id, "PWRF");
1637                 break;
1638         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1639                 strcpy(device->pnp.bus_id, "SLPF");
1640                 break;
1641         default:
1642                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1643                 /* Clean up trailing underscores (if any) */
1644                 for (i = 3; i > 1; i--) {
1645                         if (bus_id[i] == '_')
1646                                 bus_id[i] = '\0';
1647                         else
1648                                 break;
1649                 }
1650                 strcpy(device->pnp.bus_id, bus_id);
1651                 break;
1652         }
1653 }
1654
1655 /*
1656  * acpi_ata_match - see if an acpi object is an ATA device
1657  *
1658  * If an acpi object has one of the ACPI ATA methods defined,
1659  * then we can safely call it an ATA device.
1660  */
1661 bool acpi_ata_match(acpi_handle handle)
1662 {
1663         return acpi_has_method(handle, "_GTF") ||
1664                acpi_has_method(handle, "_GTM") ||
1665                acpi_has_method(handle, "_STM") ||
1666                acpi_has_method(handle, "_SDD");
1667 }
1668
1669 /*
1670  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1671  *
1672  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1673  * then we can safely call it an ejectable drive bay
1674  */
1675 bool acpi_bay_match(acpi_handle handle)
1676 {
1677         acpi_handle phandle;
1678
1679         if (!acpi_has_method(handle, "_EJ0"))
1680                 return false;
1681         if (acpi_ata_match(handle))
1682                 return true;
1683         if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1684                 return false;
1685
1686         return acpi_ata_match(phandle);
1687 }
1688
1689 bool acpi_device_is_battery(struct acpi_device *adev)
1690 {
1691         struct acpi_hardware_id *hwid;
1692
1693         list_for_each_entry(hwid, &adev->pnp.ids, list)
1694                 if (!strcmp("PNP0C0A", hwid->id))
1695                         return true;
1696
1697         return false;
1698 }
1699
1700 static bool is_ejectable_bay(struct acpi_device *adev)
1701 {
1702         acpi_handle handle = adev->handle;
1703
1704         if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1705                 return true;
1706
1707         return acpi_bay_match(handle);
1708 }
1709
1710 /*
1711  * acpi_dock_match - see if an acpi object has a _DCK method
1712  */
1713 bool acpi_dock_match(acpi_handle handle)
1714 {
1715         return acpi_has_method(handle, "_DCK");
1716 }
1717
1718 const char *acpi_device_hid(struct acpi_device *device)
1719 {
1720         struct acpi_hardware_id *hid;
1721
1722         if (list_empty(&device->pnp.ids))
1723                 return dummy_hid;
1724
1725         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1726         return hid->id;
1727 }
1728 EXPORT_SYMBOL(acpi_device_hid);
1729
1730 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1731 {
1732         struct acpi_hardware_id *id;
1733
1734         id = kmalloc(sizeof(*id), GFP_KERNEL);
1735         if (!id)
1736                 return;
1737
1738         id->id = kstrdup(dev_id, GFP_KERNEL);
1739         if (!id->id) {
1740                 kfree(id);
1741                 return;
1742         }
1743
1744         list_add_tail(&id->list, &pnp->ids);
1745         pnp->type.hardware_id = 1;
1746 }
1747
1748 /*
1749  * Old IBM workstations have a DSDT bug wherein the SMBus object
1750  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1751  * prefix.  Work around this.
1752  */
1753 static bool acpi_ibm_smbus_match(acpi_handle handle)
1754 {
1755         char node_name[ACPI_PATH_SEGMENT_LENGTH];
1756         struct acpi_buffer path = { sizeof(node_name), node_name };
1757
1758         if (!dmi_name_in_vendors("IBM"))
1759                 return false;
1760
1761         /* Look for SMBS object */
1762         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1763             strcmp("SMBS", path.pointer))
1764                 return false;
1765
1766         /* Does it have the necessary (but misnamed) methods? */
1767         if (acpi_has_method(handle, "SBI") &&
1768             acpi_has_method(handle, "SBR") &&
1769             acpi_has_method(handle, "SBW"))
1770                 return true;
1771
1772         return false;
1773 }
1774
1775 static bool acpi_object_is_system_bus(acpi_handle handle)
1776 {
1777         acpi_handle tmp;
1778
1779         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1780             tmp == handle)
1781                 return true;
1782         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1783             tmp == handle)
1784                 return true;
1785
1786         return false;
1787 }
1788
1789 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1790                                 int device_type)
1791 {
1792         acpi_status status;
1793         struct acpi_device_info *info;
1794         struct acpi_pnp_device_id_list *cid_list;
1795         int i;
1796
1797         switch (device_type) {
1798         case ACPI_BUS_TYPE_DEVICE:
1799                 if (handle == ACPI_ROOT_OBJECT) {
1800                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1801                         break;
1802                 }
1803
1804                 status = acpi_get_object_info(handle, &info);
1805                 if (ACPI_FAILURE(status)) {
1806                         pr_err(PREFIX "%s: Error reading device info\n",
1807                                         __func__);
1808                         return;
1809                 }
1810
1811                 if (info->valid & ACPI_VALID_HID) {
1812                         acpi_add_id(pnp, info->hardware_id.string);
1813                         pnp->type.platform_id = 1;
1814                 }
1815                 if (info->valid & ACPI_VALID_CID) {
1816                         cid_list = &info->compatible_id_list;
1817                         for (i = 0; i < cid_list->count; i++)
1818                                 acpi_add_id(pnp, cid_list->ids[i].string);
1819                 }
1820                 if (info->valid & ACPI_VALID_ADR) {
1821                         pnp->bus_address = info->address;
1822                         pnp->type.bus_address = 1;
1823                 }
1824                 if (info->valid & ACPI_VALID_UID)
1825                         pnp->unique_id = kstrdup(info->unique_id.string,
1826                                                         GFP_KERNEL);
1827
1828                 kfree(info);
1829
1830                 /*
1831                  * Some devices don't reliably have _HIDs & _CIDs, so add
1832                  * synthetic HIDs to make sure drivers can find them.
1833                  */
1834                 if (acpi_is_video_device(handle))
1835                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1836                 else if (acpi_bay_match(handle))
1837                         acpi_add_id(pnp, ACPI_BAY_HID);
1838                 else if (acpi_dock_match(handle))
1839                         acpi_add_id(pnp, ACPI_DOCK_HID);
1840                 else if (acpi_ibm_smbus_match(handle))
1841                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1842                 else if (list_empty(&pnp->ids) &&
1843                          acpi_object_is_system_bus(handle)) {
1844                         /* \_SB, \_TZ, LNXSYBUS */
1845                         acpi_add_id(pnp, ACPI_BUS_HID);
1846                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1847                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1848                 }
1849
1850                 break;
1851         case ACPI_BUS_TYPE_POWER:
1852                 acpi_add_id(pnp, ACPI_POWER_HID);
1853                 break;
1854         case ACPI_BUS_TYPE_PROCESSOR:
1855                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1856                 break;
1857         case ACPI_BUS_TYPE_THERMAL:
1858                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1859                 break;
1860         case ACPI_BUS_TYPE_POWER_BUTTON:
1861                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1862                 break;
1863         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1864                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1865                 break;
1866         }
1867 }
1868
1869 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1870 {
1871         struct acpi_hardware_id *id, *tmp;
1872
1873         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1874                 kfree(id->id);
1875                 kfree(id);
1876         }
1877         kfree(pnp->unique_id);
1878 }
1879
1880 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1881                              int type, unsigned long long sta)
1882 {
1883         INIT_LIST_HEAD(&device->pnp.ids);
1884         device->device_type = type;
1885         device->handle = handle;
1886         device->parent = acpi_bus_get_parent(handle);
1887         acpi_set_device_status(device, sta);
1888         acpi_device_get_busid(device);
1889         acpi_set_pnp_ids(handle, &device->pnp, type);
1890         acpi_bus_get_flags(device);
1891         device->flags.match_driver = false;
1892         device->flags.initialized = true;
1893         device->flags.visited = false;
1894         device_initialize(&device->dev);
1895         dev_set_uevent_suppress(&device->dev, true);
1896 }
1897
1898 void acpi_device_add_finalize(struct acpi_device *device)
1899 {
1900         dev_set_uevent_suppress(&device->dev, false);
1901         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1902 }
1903
1904 static int acpi_add_single_object(struct acpi_device **child,
1905                                   acpi_handle handle, int type,
1906                                   unsigned long long sta)
1907 {
1908         int result;
1909         struct acpi_device *device;
1910         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1911
1912         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1913         if (!device) {
1914                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1915                 return -ENOMEM;
1916         }
1917
1918         acpi_init_device_object(device, handle, type, sta);
1919         acpi_bus_get_power_flags(device);
1920         acpi_bus_get_wakeup_device_flags(device);
1921
1922         result = acpi_device_add(device, acpi_device_release);
1923         if (result) {
1924                 acpi_device_release(&device->dev);
1925                 return result;
1926         }
1927
1928         acpi_power_add_remove_device(device, true);
1929         acpi_device_add_finalize(device);
1930         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1931         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1932                 dev_name(&device->dev), (char *) buffer.pointer,
1933                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1934         kfree(buffer.pointer);
1935         *child = device;
1936         return 0;
1937 }
1938
1939 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1940                                     unsigned long long *sta)
1941 {
1942         acpi_status status;
1943         acpi_object_type acpi_type;
1944
1945         status = acpi_get_type(handle, &acpi_type);
1946         if (ACPI_FAILURE(status))
1947                 return -ENODEV;
1948
1949         switch (acpi_type) {
1950         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1951         case ACPI_TYPE_DEVICE:
1952                 *type = ACPI_BUS_TYPE_DEVICE;
1953                 status = acpi_bus_get_status_handle(handle, sta);
1954                 if (ACPI_FAILURE(status))
1955                         return -ENODEV;
1956                 break;
1957         case ACPI_TYPE_PROCESSOR:
1958                 *type = ACPI_BUS_TYPE_PROCESSOR;
1959                 status = acpi_bus_get_status_handle(handle, sta);
1960                 if (ACPI_FAILURE(status))
1961                         return -ENODEV;
1962                 break;
1963         case ACPI_TYPE_THERMAL:
1964                 *type = ACPI_BUS_TYPE_THERMAL;
1965                 *sta = ACPI_STA_DEFAULT;
1966                 break;
1967         case ACPI_TYPE_POWER:
1968                 *type = ACPI_BUS_TYPE_POWER;
1969                 *sta = ACPI_STA_DEFAULT;
1970                 break;
1971         default:
1972                 return -ENODEV;
1973         }
1974
1975         return 0;
1976 }
1977
1978 bool acpi_device_is_present(struct acpi_device *adev)
1979 {
1980         if (adev->status.present || adev->status.functional)
1981                 return true;
1982
1983         adev->flags.initialized = false;
1984         return false;
1985 }
1986
1987 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1988                                        char *idstr,
1989                                        const struct acpi_device_id **matchid)
1990 {
1991         const struct acpi_device_id *devid;
1992
1993         if (handler->match)
1994                 return handler->match(idstr, matchid);
1995
1996         for (devid = handler->ids; devid->id[0]; devid++)
1997                 if (!strcmp((char *)devid->id, idstr)) {
1998                         if (matchid)
1999                                 *matchid = devid;
2000
2001                         return true;
2002                 }
2003
2004         return false;
2005 }
2006
2007 static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr,
2008                                         const struct acpi_device_id **matchid)
2009 {
2010         struct acpi_scan_handler *handler;
2011
2012         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
2013                 if (acpi_scan_handler_matching(handler, idstr, matchid))
2014                         return handler;
2015
2016         return NULL;
2017 }
2018
2019 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
2020 {
2021         if (!!hotplug->enabled == !!val)
2022                 return;
2023
2024         mutex_lock(&acpi_scan_lock);
2025
2026         hotplug->enabled = val;
2027
2028         mutex_unlock(&acpi_scan_lock);
2029 }
2030
2031 static void acpi_scan_init_hotplug(struct acpi_device *adev)
2032 {
2033         struct acpi_hardware_id *hwid;
2034
2035         if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
2036                 acpi_dock_add(adev);
2037                 return;
2038         }
2039         list_for_each_entry(hwid, &adev->pnp.ids, list) {
2040                 struct acpi_scan_handler *handler;
2041
2042                 handler = acpi_scan_match_handler(hwid->id, NULL);
2043                 if (handler) {
2044                         adev->flags.hotplug_notify = true;
2045                         break;
2046                 }
2047         }
2048 }
2049
2050 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
2051                                       void *not_used, void **return_value)
2052 {
2053         struct acpi_device *device = NULL;
2054         int type;
2055         unsigned long long sta;
2056         int result;
2057
2058         acpi_bus_get_device(handle, &device);
2059         if (device)
2060                 goto out;
2061
2062         result = acpi_bus_type_and_status(handle, &type, &sta);
2063         if (result)
2064                 return AE_OK;
2065
2066         if (type == ACPI_BUS_TYPE_POWER) {
2067                 acpi_add_power_resource(handle);
2068                 return AE_OK;
2069         }
2070
2071         acpi_add_single_object(&device, handle, type, sta);
2072         if (!device)
2073                 return AE_CTRL_DEPTH;
2074
2075         acpi_scan_init_hotplug(device);
2076
2077  out:
2078         if (!*return_value)
2079                 *return_value = device;
2080
2081         return AE_OK;
2082 }
2083
2084 static int acpi_check_spi_i2c_slave(struct acpi_resource *ares, void *data)
2085 {
2086         bool *is_spi_i2c_slave_p = data;
2087
2088         if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
2089                 return 1;
2090
2091         /*
2092          * devices that are connected to UART still need to be enumerated to
2093          * platform bus
2094          */
2095         if (ares->data.common_serial_bus.type != ACPI_RESOURCE_SERIAL_TYPE_UART)
2096                 *is_spi_i2c_slave_p = true;
2097
2098          /* no need to do more checking */
2099         return -1;
2100 }
2101
2102 static void acpi_default_enumeration(struct acpi_device *device)
2103 {
2104         struct list_head resource_list;
2105         bool is_spi_i2c_slave = false;
2106
2107         if (!device->pnp.type.platform_id || device->handler)
2108                 return;
2109
2110         /*
2111          * Do not enemerate SPI/I2C slaves as they will be enuerated by their
2112          * respective parents.
2113          */
2114         INIT_LIST_HEAD(&resource_list);
2115         acpi_dev_get_resources(device, &resource_list, acpi_check_spi_i2c_slave,
2116                                &is_spi_i2c_slave);
2117         acpi_dev_free_resource_list(&resource_list);
2118         if (!is_spi_i2c_slave)
2119                 acpi_create_platform_device(device);
2120 }
2121
2122 static int acpi_scan_attach_handler(struct acpi_device *device)
2123 {
2124         struct acpi_hardware_id *hwid;
2125         int ret = 0;
2126
2127         list_for_each_entry(hwid, &device->pnp.ids, list) {
2128                 const struct acpi_device_id *devid;
2129                 struct acpi_scan_handler *handler;
2130
2131                 handler = acpi_scan_match_handler(hwid->id, &devid);
2132                 if (handler) {
2133                         if (!handler->attach) {
2134                                 device->pnp.type.platform_id = 0;
2135                                 continue;
2136                         }
2137                         device->handler = handler;
2138                         ret = handler->attach(device, devid);
2139                         if (ret > 0)
2140                                 break;
2141
2142                         device->handler = NULL;
2143                         if (ret < 0)
2144                                 break;
2145                 }
2146         }
2147         if (!ret)
2148                 acpi_default_enumeration(device);
2149
2150         return ret;
2151 }
2152
2153 static void acpi_bus_attach(struct acpi_device *device)
2154 {
2155         struct acpi_device *child;
2156         acpi_handle ejd;
2157         int ret;
2158
2159         if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
2160                 register_dock_dependent_device(device, ejd);
2161
2162         acpi_bus_get_status(device);
2163         /* Skip devices that are not present. */
2164         if (!acpi_device_is_present(device)) {
2165                 device->flags.visited = false;
2166                 return;
2167         }
2168         if (device->handler)
2169                 goto ok;
2170
2171         if (!device->flags.initialized) {
2172                 acpi_bus_update_power(device, NULL);
2173                 device->flags.initialized = true;
2174         }
2175         device->flags.visited = false;
2176         ret = acpi_scan_attach_handler(device);
2177         if (ret < 0)
2178                 return;
2179
2180         device->flags.match_driver = true;
2181         if (!ret) {
2182                 ret = device_attach(&device->dev);
2183                 if (ret < 0)
2184                         return;
2185         }
2186         device->flags.visited = true;
2187
2188  ok:
2189         list_for_each_entry(child, &device->children, node)
2190                 acpi_bus_attach(child);
2191 }
2192
2193 /**
2194  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2195  * @handle: Root of the namespace scope to scan.
2196  *
2197  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2198  * found devices.
2199  *
2200  * If no devices were found, -ENODEV is returned, but it does not mean that
2201  * there has been a real error.  There just have been no suitable ACPI objects
2202  * in the table trunk from which the kernel could create a device and add an
2203  * appropriate driver.
2204  *
2205  * Must be called under acpi_scan_lock.
2206  */
2207 int acpi_bus_scan(acpi_handle handle)
2208 {
2209         void *device = NULL;
2210
2211         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
2212                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2213                                     acpi_bus_check_add, NULL, NULL, &device);
2214
2215         if (device) {
2216                 acpi_bus_attach(device);
2217                 return 0;
2218         }
2219         return -ENODEV;
2220 }
2221 EXPORT_SYMBOL(acpi_bus_scan);
2222
2223 /**
2224  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2225  * @adev: Root of the ACPI namespace scope to walk.
2226  *
2227  * Must be called under acpi_scan_lock.
2228  */
2229 void acpi_bus_trim(struct acpi_device *adev)
2230 {
2231         struct acpi_scan_handler *handler = adev->handler;
2232         struct acpi_device *child;
2233
2234         list_for_each_entry_reverse(child, &adev->children, node)
2235                 acpi_bus_trim(child);
2236
2237         adev->flags.match_driver = false;
2238         if (handler) {
2239                 if (handler->detach)
2240                         handler->detach(adev);
2241
2242                 adev->handler = NULL;
2243         } else {
2244                 device_release_driver(&adev->dev);
2245         }
2246         /*
2247          * Most likely, the device is going away, so put it into D3cold before
2248          * that.
2249          */
2250         acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2251         adev->flags.initialized = false;
2252         adev->flags.visited = false;
2253 }
2254 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2255
2256 static int acpi_bus_scan_fixed(void)
2257 {
2258         int result = 0;
2259
2260         /*
2261          * Enumerate all fixed-feature devices.
2262          */
2263         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2264                 struct acpi_device *device = NULL;
2265
2266                 result = acpi_add_single_object(&device, NULL,
2267                                                 ACPI_BUS_TYPE_POWER_BUTTON,
2268                                                 ACPI_STA_DEFAULT);
2269                 if (result)
2270                         return result;
2271
2272                 device->flags.match_driver = true;
2273                 result = device_attach(&device->dev);
2274                 if (result < 0)
2275                         return result;
2276
2277                 device_init_wakeup(&device->dev, true);
2278         }
2279
2280         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2281                 struct acpi_device *device = NULL;
2282
2283                 result = acpi_add_single_object(&device, NULL,
2284                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2285                                                 ACPI_STA_DEFAULT);
2286                 if (result)
2287                         return result;
2288
2289                 device->flags.match_driver = true;
2290                 result = device_attach(&device->dev);
2291         }
2292
2293         return result < 0 ? result : 0;
2294 }
2295
2296 int __init acpi_scan_init(void)
2297 {
2298         int result;
2299
2300         result = bus_register(&acpi_bus_type);
2301         if (result) {
2302                 /* We don't want to quit even if we failed to add suspend/resume */
2303                 printk(KERN_ERR PREFIX "Could not register bus type\n");
2304         }
2305
2306         acpi_pci_root_init();
2307         acpi_pci_link_init();
2308         acpi_processor_init();
2309         acpi_lpss_init();
2310         acpi_cmos_rtc_init();
2311         acpi_container_init();
2312         acpi_memory_hotplug_init();
2313         acpi_pnp_init();
2314
2315         mutex_lock(&acpi_scan_lock);
2316         /*
2317          * Enumerate devices in the ACPI namespace.
2318          */
2319         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2320         if (result)
2321                 goto out;
2322
2323         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2324         if (result)
2325                 goto out;
2326
2327         /* Fixed feature devices do not exist on HW-reduced platform */
2328         if (!acpi_gbl_reduced_hardware) {
2329                 result = acpi_bus_scan_fixed();
2330                 if (result) {
2331                         acpi_detach_data(acpi_root->handle,
2332                                          acpi_scan_drop_device);
2333                         acpi_device_del(acpi_root);
2334                         put_device(&acpi_root->dev);
2335                         goto out;
2336                 }
2337         }
2338
2339         acpi_update_all_gpes();
2340
2341  out:
2342         mutex_unlock(&acpi_scan_lock);
2343         return result;
2344 }