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