drivers/acpi/scan.c

   1 /*
   2  * scan.c - support for transforming the ACPI namespace into individual objects
   3  */
   4
   5 #include <linux/module.h>
   6 #include <linux/init.h>
   7 #include <linux/slab.h>
   8 #include <linux/kernel.h>
   9 #include <linux/acpi.h>
  10 #include <linux/signal.h>
  11 #include <linux/kthread.h>
  12 #include <linux/dmi.h>
  13 #include <linux/nls.h>
  14
  15 #include <acpi/acpi_drivers.h>
  16
  17 #include "internal.h"
  18
  19 #define _COMPONENT              ACPI_BUS_COMPONENT
  20 ACPI_MODULE_NAME("scan");
  21 #define STRUCT_TO_INT(s)        (*((int*)&s))
  22 extern struct acpi_device *acpi_root;
  23
  24 #define ACPI_BUS_CLASS                  "system_bus"
  25 #define ACPI_BUS_HID                    "LNXSYBUS"
  26 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  27
  28 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
  29
  30 /*
  31  * If set, devices will be hot-removed even if they cannot be put offline
  32  * gracefully (from the kernel's standpoint).
  33  */
  34 bool acpi_force_hot_remove;
  35
  36 static const char *dummy_hid = "device";
  37
  38 static LIST_HEAD(acpi_bus_id_list);
  39 static DEFINE_MUTEX(acpi_scan_lock);
  40 static LIST_HEAD(acpi_scan_handlers_list);
  41 DEFINE_MUTEX(acpi_device_lock);
  42 LIST_HEAD(acpi_wakeup_device_list);
  43
  44 struct acpi_device_bus_id{
  45         char bus_id[15];
  46         unsigned int instance_no;
  47         struct list_head node;
  48 };
  49
  50 void acpi_scan_lock_acquire(void)
  51 {
  52         mutex_lock(&acpi_scan_lock);
  53 }
  54 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
  55
  56 void acpi_scan_lock_release(void)
  57 {
  58         mutex_unlock(&acpi_scan_lock);
  59 }
  60 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
  61
  62 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
  63 {
  64         if (!handler || !handler->attach)
  65                 return -EINVAL;
  66
  67         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
  68         return 0;
  69 }
  70
  71 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
  72                                        const char *hotplug_profile_name)
  73 {
  74         int error;
  75
  76         error = acpi_scan_add_handler(handler);
  77         if (error)
  78                 return error;
  79
  80         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
  81         return 0;
  82 }
  83
  84 /*
  85  * Creates hid/cid(s) string needed for modalias and uevent
  86  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
  87  * char *modalias: "acpi:IBM0001:ACPI0001"
  88 */
  89 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
  90                            int size)
  91 {
  92         int len;
  93         int count;
  94         struct acpi_hardware_id *id;
  95
  96         if (list_empty(&acpi_dev->pnp.ids))
  97                 return 0;
  98
  99         len = snprintf(modalias, size, "acpi:");
 100         size -= len;
 101
 102         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
 103                 count = snprintf(&modalias[len], size, "%s:", id->id);
 104                 if (count < 0 || count >= size)
 105                         return -EINVAL;
 106                 len += count;
 107                 size -= count;
 108         }
 109
 110         modalias[len] = '\0';
 111         return len;
 112 }
 113
 114 static ssize_t
 115 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
 116         struct acpi_device *acpi_dev = to_acpi_device(dev);
 117         int len;
 118
 119         /* Device has no HID and no CID or string is >1024 */
 120         len = create_modalias(acpi_dev, buf, 1024);
 121         if (len <= 0)
 122                 return 0;
 123         buf[len++] = '\n';
 124         return len;
 125 }
 126 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
 127
 128 static acpi_status acpi_bus_offline_companions(acpi_handle handle, u32 lvl,
 129                                                void *data, void **ret_p)
 130 {
 131         struct acpi_device *device = NULL;
 132         struct acpi_device_physical_node *pn;
 133         bool second_pass = (bool)data;
 134         acpi_status status = AE_OK;
 135
 136         if (acpi_bus_get_device(handle, &device))
 137                 return AE_OK;
 138
 139         mutex_lock(&device->physical_node_lock);
 140
 141         list_for_each_entry(pn, &device->physical_node_list, node) {
 142                 int ret;
 143
 144                 if (second_pass) {
 145                         /* Skip devices offlined by the first pass. */
 146                         if (pn->put_online)
 147                                 continue;
 148                 } else {
 149                         pn->put_online = false;
 150                 }
 151                 ret = device_offline(pn->dev);
 152                 if (acpi_force_hot_remove)
 153                         continue;
 154
 155                 if (ret >= 0) {
 156                         pn->put_online = !ret;
 157                 } else {
 158                         *ret_p = pn->dev;
 159                         if (second_pass) {
 160                                 status = AE_ERROR;
 161                                 break;
 162                         }
 163                 }
 164         }
 165
 166         mutex_unlock(&device->physical_node_lock);
 167
 168         return status;
 169 }
 170
 171 static acpi_status acpi_bus_online_companions(acpi_handle handle, u32 lvl,
 172                                               void *data, void **ret_p)
 173 {
 174         struct acpi_device *device = NULL;
 175         struct acpi_device_physical_node *pn;
 176
 177         if (acpi_bus_get_device(handle, &device))
 178                 return AE_OK;
 179
 180         mutex_lock(&device->physical_node_lock);
 181
 182         list_for_each_entry(pn, &device->physical_node_list, node)
 183                 if (pn->put_online) {
 184                         device_online(pn->dev);
 185                         pn->put_online = false;
 186                 }
 187
 188         mutex_unlock(&device->physical_node_lock);
 189
 190         return AE_OK;
 191 }
 192
 193 static int acpi_scan_hot_remove(struct acpi_device *device)
 194 {
 195         acpi_handle handle = device->handle;
 196         acpi_handle not_used;
 197         struct acpi_object_list arg_list;
 198         union acpi_object arg;
 199         struct device *errdev;
 200         acpi_status status;
 201         unsigned long long sta;
 202
 203         /* If there is no handle, the device node has been unregistered. */
 204         if (!handle) {
 205                 dev_dbg(&device->dev, "ACPI handle missing\n");
 206                 put_device(&device->dev);
 207                 return -EINVAL;
 208         }
 209
 210         lock_device_hotplug();
 211
 212         /*
 213          * Carry out two passes here and ignore errors in the first pass,
 214          * because if the devices in question are memory blocks and
 215          * CONFIG_MEMCG is set, one of the blocks may hold data structures
 216          * that the other blocks depend on, but it is not known in advance which
 217          * block holds them.
 218          *
 219          * If the first pass is successful, the second one isn't needed, though.
 220          */
 221         errdev = NULL;
 222         acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 223                             NULL, acpi_bus_offline_companions,
 224                             (void *)false, (void **)&errdev);
 225         acpi_bus_offline_companions(handle, 0, (void *)false, (void **)&errdev);
 226         if (errdev) {
 227                 errdev = NULL;
 228                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 229                                     NULL, acpi_bus_offline_companions,
 230                                     (void *)true , (void **)&errdev);
 231                 if (!errdev || acpi_force_hot_remove)
 232                         acpi_bus_offline_companions(handle, 0, (void *)true,
 233                                                     (void **)&errdev);
 234
 235                 if (errdev && !acpi_force_hot_remove) {
 236                         dev_warn(errdev, "Offline failed.\n");
 237                         acpi_bus_online_companions(handle, 0, NULL, NULL);
 238                         acpi_walk_namespace(ACPI_TYPE_ANY, handle,
 239                                             ACPI_UINT32_MAX,
 240                                             acpi_bus_online_companions, NULL,
 241                                             NULL, NULL);
 242
 243                         unlock_device_hotplug();
 244
 245                         put_device(&device->dev);
 246                         return -EBUSY;
 247                 }
 248         }
 249
 250         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 251                 "Hot-removing device %s...\n", dev_name(&device->dev)));
 252
 253         acpi_bus_trim(device);
 254
 255         unlock_device_hotplug();
 256
 257         /* Device node has been unregistered. */
 258         put_device(&device->dev);
 259         device = NULL;
 260
 261         if (ACPI_SUCCESS(acpi_get_handle(handle, "_LCK", &not_used))) {
 262                 arg_list.count = 1;
 263                 arg_list.pointer = &arg;
 264                 arg.type = ACPI_TYPE_INTEGER;
 265                 arg.integer.value = 0;
 266                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
 267         }
 268
 269         arg_list.count = 1;
 270         arg_list.pointer = &arg;
 271         arg.type = ACPI_TYPE_INTEGER;
 272         arg.integer.value = 1;
 273
 274         /*
 275          * TBD: _EJD support.
 276          */
 277         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
 278         if (ACPI_FAILURE(status)) {
 279                 if (status == AE_NOT_FOUND) {
 280                         return -ENODEV;
 281                 } else {
 282                         acpi_handle_warn(handle, "Eject failed (0x%x)\n",
 283                                                                 status);
 284                         return -EIO;
 285                 }
 286         }
 287
 288         /*
 289          * Verify if eject was indeed successful.  If not, log an error
 290          * message.  No need to call _OST since _EJ0 call was made OK.
 291          */
 292         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 293         if (ACPI_FAILURE(status)) {
 294                 acpi_handle_warn(handle,
 295                         "Status check after eject failed (0x%x)\n", status);
 296         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
 297                 acpi_handle_warn(handle,
 298                         "Eject incomplete - status 0x%llx\n", sta);
 299         }
 300
 301         return 0;
 302 }
 303
 304 static void acpi_bus_device_eject(void *context)
 305 {
 306         acpi_handle handle = context;
 307         struct acpi_device *device = NULL;
 308         struct acpi_scan_handler *handler;
 309         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 310
 311         mutex_lock(&acpi_scan_lock);
 312
 313         acpi_bus_get_device(handle, &device);
 314         if (!device)
 315                 goto err_out;
 316
 317         handler = device->handler;
 318         if (!handler || !handler->hotplug.enabled) {
 319                 ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 320                 goto err_out;
 321         }
 322         acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST,
 323                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 324         if (handler->hotplug.mode == AHM_CONTAINER) {
 325                 device->flags.eject_pending = true;
 326                 kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE);
 327         } else {
 328                 int error;
 329
 330                 get_device(&device->dev);
 331                 error = acpi_scan_hot_remove(device);
 332                 if (error)
 333                         goto err_out;
 334         }
 335
 336  out:
 337         mutex_unlock(&acpi_scan_lock);
 338         return;
 339
 340  err_out:
 341         acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST, ost_code,
 342                                   NULL);
 343         goto out;
 344 }
 345
 346 static void acpi_scan_bus_device_check(acpi_handle handle, u32 ost_source)
 347 {
 348         struct acpi_device *device = NULL;
 349         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 350         int error;
 351
 352         mutex_lock(&acpi_scan_lock);
 353         lock_device_hotplug();
 354
 355         if (ost_source != ACPI_NOTIFY_BUS_CHECK) {
 356                 acpi_bus_get_device(handle, &device);
 357                 if (device) {
 358                         dev_warn(&device->dev, "Attempt to re-insert\n");
 359                         goto out;
 360                 }
 361         }
 362         acpi_evaluate_hotplug_ost(handle, ost_source,
 363                                   ACPI_OST_SC_INSERT_IN_PROGRESS, NULL);
 364         error = acpi_bus_scan(handle);
 365         if (error) {
 366                 acpi_handle_warn(handle, "Namespace scan failure\n");
 367                 goto out;
 368         }
 369         error = acpi_bus_get_device(handle, &device);
 370         if (error) {
 371                 acpi_handle_warn(handle, "Missing device node object\n");
 372                 goto out;
 373         }
 374         ost_code = ACPI_OST_SC_SUCCESS;
 375         if (device->handler && device->handler->hotplug.mode == AHM_CONTAINER)
 376                 kobject_uevent(&device->dev.kobj, KOBJ_ONLINE);
 377
 378  out:
 379         unlock_device_hotplug();
 380         acpi_evaluate_hotplug_ost(handle, ost_source, ost_code, NULL);
 381         mutex_unlock(&acpi_scan_lock);
 382 }
 383
 384 static void acpi_scan_bus_check(void *context)
 385 {
 386         acpi_scan_bus_device_check((acpi_handle)context,
 387                                    ACPI_NOTIFY_BUS_CHECK);
 388 }
 389
 390 static void acpi_scan_device_check(void *context)
 391 {
 392         acpi_scan_bus_device_check((acpi_handle)context,
 393                                    ACPI_NOTIFY_DEVICE_CHECK);
 394 }
 395
 396 static void acpi_hotplug_unsupported(acpi_handle handle, u32 type)
 397 {
 398         u32 ost_status;
 399
 400         switch (type) {
 401         case ACPI_NOTIFY_BUS_CHECK:
 402                 acpi_handle_debug(handle,
 403                         "ACPI_NOTIFY_BUS_CHECK event: unsupported\n");
 404                 ost_status = ACPI_OST_SC_INSERT_NOT_SUPPORTED;
 405                 break;
 406         case ACPI_NOTIFY_DEVICE_CHECK:
 407                 acpi_handle_debug(handle,
 408                         "ACPI_NOTIFY_DEVICE_CHECK event: unsupported\n");
 409                 ost_status = ACPI_OST_SC_INSERT_NOT_SUPPORTED;
 410                 break;
 411         case ACPI_NOTIFY_EJECT_REQUEST:
 412                 acpi_handle_debug(handle,
 413                         "ACPI_NOTIFY_EJECT_REQUEST event: unsupported\n");
 414                 ost_status = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 415                 break;
 416         default:
 417                 /* non-hotplug event; possibly handled by other handler */
 418                 return;
 419         }
 420
 421         acpi_evaluate_hotplug_ost(handle, type, ost_status, NULL);
 422 }
 423
 424 static void acpi_hotplug_notify_cb(acpi_handle handle, u32 type, void *data)
 425 {
 426         acpi_osd_exec_callback callback;
 427         struct acpi_scan_handler *handler = data;
 428         acpi_status status;
 429
 430         if (!handler->hotplug.enabled)
 431                 return acpi_hotplug_unsupported(handle, type);
 432
 433         switch (type) {
 434         case ACPI_NOTIFY_BUS_CHECK:
 435                 acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
 436                 callback = acpi_scan_bus_check;
 437                 break;
 438         case ACPI_NOTIFY_DEVICE_CHECK:
 439                 acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
 440                 callback = acpi_scan_device_check;
 441                 break;
 442         case ACPI_NOTIFY_EJECT_REQUEST:
 443                 acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
 444                 callback = acpi_bus_device_eject;
 445                 break;
 446         default:
 447                 /* non-hotplug event; possibly handled by other handler */
 448                 return;
 449         }
 450         status = acpi_os_hotplug_execute(callback, handle);
 451         if (ACPI_FAILURE(status))
 452                 acpi_evaluate_hotplug_ost(handle, type,
 453                                           ACPI_OST_SC_NON_SPECIFIC_FAILURE,
 454                                           NULL);
 455 }
 456
 457 /**
 458  * acpi_bus_hot_remove_device: hot-remove a device and its children
 459  * @context: struct acpi_eject_event pointer (freed in this func)
 460  *
 461  * Hot-remove a device and its children. This function frees up the
 462  * memory space passed by arg context, so that the caller may call
 463  * this function asynchronously through acpi_os_hotplug_execute().
 464  */
 465 void acpi_bus_hot_remove_device(void *context)
 466 {
 467         struct acpi_eject_event *ej_event = context;
 468         struct acpi_device *device = ej_event->device;
 469         acpi_handle handle = device->handle;
 470         int error;
 471
 472         mutex_lock(&acpi_scan_lock);
 473
 474         error = acpi_scan_hot_remove(device);
 475         if (error && handle)
 476                 acpi_evaluate_hotplug_ost(handle, ej_event->event,
 477                                           ACPI_OST_SC_NON_SPECIFIC_FAILURE,
 478                                           NULL);
 479
 480         mutex_unlock(&acpi_scan_lock);
 481         kfree(context);
 482 }
 483 EXPORT_SYMBOL(acpi_bus_hot_remove_device);
 484
 485 static ssize_t real_power_state_show(struct device *dev,
 486                                      struct device_attribute *attr, char *buf)
 487 {
 488         struct acpi_device *adev = to_acpi_device(dev);
 489         int state;
 490         int ret;
 491
 492         ret = acpi_device_get_power(adev, &state);
 493         if (ret)
 494                 return ret;
 495
 496         return sprintf(buf, "%s\n", acpi_power_state_string(state));
 497 }
 498
 499 static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL);
 500
 501 static ssize_t power_state_show(struct device *dev,
 502                                 struct device_attribute *attr, char *buf)
 503 {
 504         struct acpi_device *adev = to_acpi_device(dev);
 505
 506         return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
 507 }
 508
 509 static DEVICE_ATTR(power_state, 0444, power_state_show, NULL);
 510
 511 static ssize_t
 512 acpi_eject_store(struct device *d, struct device_attribute *attr,
 513                 const char *buf, size_t count)
 514 {
 515         struct acpi_device *acpi_device = to_acpi_device(d);
 516         struct acpi_eject_event *ej_event;
 517         acpi_object_type not_used;
 518         acpi_status status;
 519         u32 ost_source;
 520         int ret;
 521
 522         if (!count || buf[0] != '1')
 523                 return -EINVAL;
 524
 525         if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
 526             && !acpi_device->driver)
 527                 return -ENODEV;
 528
 529         status = acpi_get_type(acpi_device->handle, &not_used);
 530         if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
 531                 return -ENODEV;
 532
 533         mutex_lock(&acpi_scan_lock);
 534
 535         if (acpi_device->flags.eject_pending) {
 536                 /* ACPI eject notification event. */
 537                 ost_source = ACPI_NOTIFY_EJECT_REQUEST;
 538                 acpi_device->flags.eject_pending = 0;
 539         } else {
 540                 /* Eject initiated by user space. */
 541                 ost_source = ACPI_OST_EC_OSPM_EJECT;
 542         }
 543         ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
 544         if (!ej_event) {
 545                 ret = -ENOMEM;
 546                 goto err_out;
 547         }
 548         acpi_evaluate_hotplug_ost(acpi_device->handle, ost_source,
 549                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 550         ej_event->device = acpi_device;
 551         ej_event->event = ost_source;
 552         get_device(&acpi_device->dev);
 553         status = acpi_os_hotplug_execute(acpi_bus_hot_remove_device, ej_event);
 554         if (ACPI_FAILURE(status)) {
 555                 put_device(&acpi_device->dev);
 556                 kfree(ej_event);
 557                 ret = status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
 558                 goto err_out;
 559         }
 560         ret = count;
 561
 562  out:
 563         mutex_unlock(&acpi_scan_lock);
 564         return ret;
 565
 566  err_out:
 567         acpi_evaluate_hotplug_ost(acpi_device->handle, ost_source,
 568                                   ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
 569         goto out;
 570 }
 571
 572 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 573
 574 static ssize_t
 575 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 576         struct acpi_device *acpi_dev = to_acpi_device(dev);
 577
 578         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
 579 }
 580 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 581
 582 static ssize_t acpi_device_uid_show(struct device *dev,
 583                                     struct device_attribute *attr, char *buf)
 584 {
 585         struct acpi_device *acpi_dev = to_acpi_device(dev);
 586
 587         return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
 588 }
 589 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
 590
 591 static ssize_t acpi_device_adr_show(struct device *dev,
 592                                     struct device_attribute *attr, char *buf)
 593 {
 594         struct acpi_device *acpi_dev = to_acpi_device(dev);
 595
 596         return sprintf(buf, "0x%08x\n",
 597                        (unsigned int)(acpi_dev->pnp.bus_address));
 598 }
 599 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
 600
 601 static ssize_t
 602 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 603         struct acpi_device *acpi_dev = to_acpi_device(dev);
 604         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 605         int result;
 606
 607         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 608         if (result)
 609                 goto end;
 610
 611         result = sprintf(buf, "%s\n", (char*)path.pointer);
 612         kfree(path.pointer);
 613 end:
 614         return result;
 615 }
 616 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 617
 618 /* sysfs file that shows description text from the ACPI _STR method */
 619 static ssize_t description_show(struct device *dev,
 620                                 struct device_attribute *attr,
 621                                 char *buf) {
 622         struct acpi_device *acpi_dev = to_acpi_device(dev);
 623         int result;
 624
 625         if (acpi_dev->pnp.str_obj == NULL)
 626                 return 0;
 627
 628         /*
 629          * The _STR object contains a Unicode identifier for a device.
 630          * We need to convert to utf-8 so it can be displayed.
 631          */
 632         result = utf16s_to_utf8s(
 633                 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
 634                 acpi_dev->pnp.str_obj->buffer.length,
 635                 UTF16_LITTLE_ENDIAN, buf,
 636                 PAGE_SIZE);
 637
 638         buf[result++] = '\n';
 639
 640         return result;
 641 }
 642 static DEVICE_ATTR(description, 0444, description_show, NULL);
 643
 644 static ssize_t
 645 acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
 646                      char *buf) {
 647         struct acpi_device *acpi_dev = to_acpi_device(dev);
 648
 649         return sprintf(buf, "%lu\n", acpi_dev->pnp.sun);
 650 }
 651 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
 652
 653 static int acpi_device_setup_files(struct acpi_device *dev)
 654 {
 655         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 656         acpi_status status;
 657         acpi_handle temp;
 658         unsigned long long sun;
 659         int result = 0;
 660
 661         /*
 662          * Devices gotten from FADT don't have a "path" attribute
 663          */
 664         if (dev->handle) {
 665                 result = device_create_file(&dev->dev, &dev_attr_path);
 666                 if (result)
 667                         goto end;
 668         }
 669
 670         if (!list_empty(&dev->pnp.ids)) {
 671                 result = device_create_file(&dev->dev, &dev_attr_hid);
 672                 if (result)
 673                         goto end;
 674
 675                 result = device_create_file(&dev->dev, &dev_attr_modalias);
 676                 if (result)
 677                         goto end;
 678         }
 679
 680         /*
 681          * If device has _STR, 'description' file is created
 682          */
 683         status = acpi_get_handle(dev->handle, "_STR", &temp);
 684         if (ACPI_SUCCESS(status)) {
 685                 status = acpi_evaluate_object(dev->handle, "_STR",
 686                                         NULL, &buffer);
 687                 if (ACPI_FAILURE(status))
 688                         buffer.pointer = NULL;
 689                 dev->pnp.str_obj = buffer.pointer;
 690                 result = device_create_file(&dev->dev, &dev_attr_description);
 691                 if (result)
 692                         goto end;
 693         }
 694
 695         if (dev->pnp.type.bus_address)
 696                 result = device_create_file(&dev->dev, &dev_attr_adr);
 697         if (dev->pnp.unique_id)
 698                 result = device_create_file(&dev->dev, &dev_attr_uid);
 699
 700         status = acpi_evaluate_integer(dev->handle, "_SUN", NULL, &sun);
 701         if (ACPI_SUCCESS(status)) {
 702                 dev->pnp.sun = (unsigned long)sun;
 703                 result = device_create_file(&dev->dev, &dev_attr_sun);
 704                 if (result)
 705                         goto end;
 706         } else {
 707                 dev->pnp.sun = (unsigned long)-1;
 708         }
 709
 710         /*
 711          * If device has _EJ0, 'eject' file is created that is used to trigger
 712          * hot-removal function from userland.
 713          */
 714         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 715         if (ACPI_SUCCESS(status)) {
 716                 result = device_create_file(&dev->dev, &dev_attr_eject);
 717                 if (result)
 718                         return result;
 719         }
 720
 721         if (dev->flags.power_manageable) {
 722                 result = device_create_file(&dev->dev, &dev_attr_power_state);
 723                 if (result)
 724                         return result;
 725
 726                 if (dev->power.flags.power_resources)
 727                         result = device_create_file(&dev->dev,
 728                                                     &dev_attr_real_power_state);
 729         }
 730
 731 end:
 732         return result;
 733 }
 734
 735 static void acpi_device_remove_files(struct acpi_device *dev)
 736 {
 737         acpi_status status;
 738         acpi_handle temp;
 739
 740         if (dev->flags.power_manageable) {
 741                 device_remove_file(&dev->dev, &dev_attr_power_state);
 742                 if (dev->power.flags.power_resources)
 743                         device_remove_file(&dev->dev,
 744                                            &dev_attr_real_power_state);
 745         }
 746
 747         /*
 748          * If device has _STR, remove 'description' file
 749          */
 750         status = acpi_get_handle(dev->handle, "_STR", &temp);
 751         if (ACPI_SUCCESS(status)) {
 752                 kfree(dev->pnp.str_obj);
 753                 device_remove_file(&dev->dev, &dev_attr_description);
 754         }
 755         /*
 756          * If device has _EJ0, remove 'eject' file.
 757          */
 758         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 759         if (ACPI_SUCCESS(status))
 760                 device_remove_file(&dev->dev, &dev_attr_eject);
 761
 762         status = acpi_get_handle(dev->handle, "_SUN", &temp);
 763         if (ACPI_SUCCESS(status))
 764                 device_remove_file(&dev->dev, &dev_attr_sun);
 765
 766         if (dev->pnp.unique_id)
 767                 device_remove_file(&dev->dev, &dev_attr_uid);
 768         if (dev->pnp.type.bus_address)
 769                 device_remove_file(&dev->dev, &dev_attr_adr);
 770         device_remove_file(&dev->dev, &dev_attr_modalias);
 771         device_remove_file(&dev->dev, &dev_attr_hid);
 772         if (dev->handle)
 773                 device_remove_file(&dev->dev, &dev_attr_path);
 774 }
 775 /* --------------------------------------------------------------------------
 776                         ACPI Bus operations
 777    -------------------------------------------------------------------------- */
 778
 779 static const struct acpi_device_id *__acpi_match_device(
 780         struct acpi_device *device, const struct acpi_device_id *ids)
 781 {
 782         const struct acpi_device_id *id;
 783         struct acpi_hardware_id *hwid;
 784
 785         /*
 786          * If the device is not present, it is unnecessary to load device
 787          * driver for it.
 788          */
 789         if (!device->status.present)
 790                 return NULL;
 791
 792         for (id = ids; id->id[0]; id++)
 793                 list_for_each_entry(hwid, &device->pnp.ids, list)
 794                         if (!strcmp((char *) id->id, hwid->id))
 795                                 return id;
 796
 797         return NULL;
 798 }
 799
 800 /**
 801  * acpi_match_device - Match a struct device against a given list of ACPI IDs
 802  * @ids: Array of struct acpi_device_id object to match against.
 803  * @dev: The device structure to match.
 804  *
 805  * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
 806  * object for that handle and use that object to match against a given list of
 807  * device IDs.
 808  *
 809  * Return a pointer to the first matching ID on success or %NULL on failure.
 810  */
 811 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
 812                                                const struct device *dev)
 813 {
 814         struct acpi_device *adev;
 815         acpi_handle handle = ACPI_HANDLE(dev);
 816
 817         if (!ids || !handle || acpi_bus_get_device(handle, &adev))
 818                 return NULL;
 819
 820         return __acpi_match_device(adev, ids);
 821 }
 822 EXPORT_SYMBOL_GPL(acpi_match_device);
 823
 824 int acpi_match_device_ids(struct acpi_device *device,
 825                           const struct acpi_device_id *ids)
 826 {
 827         return __acpi_match_device(device, ids) ? 0 : -ENOENT;
 828 }
 829 EXPORT_SYMBOL(acpi_match_device_ids);
 830
 831 static void acpi_free_power_resources_lists(struct acpi_device *device)
 832 {
 833         int i;
 834
 835         if (device->wakeup.flags.valid)
 836                 acpi_power_resources_list_free(&device->wakeup.resources);
 837
 838         if (!device->flags.power_manageable)
 839                 return;
 840
 841         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 842                 struct acpi_device_power_state *ps = &device->power.states[i];
 843                 acpi_power_resources_list_free(&ps->resources);
 844         }
 845 }
 846
 847 static void acpi_device_release(struct device *dev)
 848 {
 849         struct acpi_device *acpi_dev = to_acpi_device(dev);
 850
 851         acpi_free_pnp_ids(&acpi_dev->pnp);
 852         acpi_free_power_resources_lists(acpi_dev);
 853         kfree(acpi_dev);
 854 }
 855
 856 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 857 {
 858         struct acpi_device *acpi_dev = to_acpi_device(dev);
 859         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 860
 861         return acpi_dev->flags.match_driver
 862                 && !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 863 }
 864
 865 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 866 {
 867         struct acpi_device *acpi_dev = to_acpi_device(dev);
 868         int len;
 869
 870         if (list_empty(&acpi_dev->pnp.ids))
 871                 return 0;
 872
 873         if (add_uevent_var(env, "MODALIAS="))
 874                 return -ENOMEM;
 875         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 876                               sizeof(env->buf) - env->buflen);
 877         if (len >= (sizeof(env->buf) - env->buflen))
 878                 return -ENOMEM;
 879         env->buflen += len;
 880         return 0;
 881 }
 882
 883 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 884 {
 885         struct acpi_device *device = data;
 886
 887         device->driver->ops.notify(device, event);
 888 }
 889
 890 static acpi_status acpi_device_notify_fixed(void *data)
 891 {
 892         struct acpi_device *device = data;
 893
 894         /* Fixed hardware devices have no handles */
 895         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 896         return AE_OK;
 897 }
 898
 899 static int acpi_device_install_notify_handler(struct acpi_device *device)
 900 {
 901         acpi_status status;
 902
 903         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 904                 status =
 905                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 906                                                      acpi_device_notify_fixed,
 907                                                      device);
 908         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 909                 status =
 910                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 911                                                      acpi_device_notify_fixed,
 912                                                      device);
 913         else
 914                 status = acpi_install_notify_handler(device->handle,
 915                                                      ACPI_DEVICE_NOTIFY,
 916                                                      acpi_device_notify,
 917                                                      device);
 918
 919         if (ACPI_FAILURE(status))
 920                 return -EINVAL;
 921         return 0;
 922 }
 923
 924 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 925 {
 926         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 927                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 928                                                 acpi_device_notify_fixed);
 929         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 930                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 931                                                 acpi_device_notify_fixed);
 932         else
 933                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 934                                            acpi_device_notify);
 935 }
 936
 937 static int acpi_device_probe(struct device *dev)
 938 {
 939         struct acpi_device *acpi_dev = to_acpi_device(dev);
 940         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 941         int ret;
 942
 943         if (acpi_dev->handler)
 944                 return -EINVAL;
 945
 946         if (!acpi_drv->ops.add)
 947                 return -ENOSYS;
 948
 949         ret = acpi_drv->ops.add(acpi_dev);
 950         if (ret)
 951                 return ret;
 952
 953         acpi_dev->driver = acpi_drv;
 954         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 955                           "Driver [%s] successfully bound to device [%s]\n",
 956                           acpi_drv->name, acpi_dev->pnp.bus_id));
 957
 958         if (acpi_drv->ops.notify) {
 959                 ret = acpi_device_install_notify_handler(acpi_dev);
 960                 if (ret) {
 961                         if (acpi_drv->ops.remove)
 962                                 acpi_drv->ops.remove(acpi_dev);
 963
 964                         acpi_dev->driver = NULL;
 965                         acpi_dev->driver_data = NULL;
 966                         return ret;
 967                 }
 968         }
 969
 970         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
 971                           acpi_drv->name, acpi_dev->pnp.bus_id));
 972         get_device(dev);
 973         return 0;
 974 }
 975
 976 static int acpi_device_remove(struct device * dev)
 977 {
 978         struct acpi_device *acpi_dev = to_acpi_device(dev);
 979         struct acpi_driver *acpi_drv = acpi_dev->driver;
 980
 981         if (acpi_drv) {
 982                 if (acpi_drv->ops.notify)
 983                         acpi_device_remove_notify_handler(acpi_dev);
 984                 if (acpi_drv->ops.remove)
 985                         acpi_drv->ops.remove(acpi_dev);
 986         }
 987         acpi_dev->driver = NULL;
 988         acpi_dev->driver_data = NULL;
 989
 990         put_device(dev);
 991         return 0;
 992 }
 993
 994 struct bus_type acpi_bus_type = {
 995         .name           = "acpi",
 996         .match          = acpi_bus_match,
 997         .probe          = acpi_device_probe,
 998         .remove         = acpi_device_remove,
 999         .uevent         = acpi_device_uevent,
1000 };
1001
1002 static void acpi_bus_data_handler(acpi_handle handle, void *context)
1003 {
1004         /* Intentionally empty. */
1005 }
1006
1007 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
1008 {
1009         acpi_status status;
1010
1011         if (!device)
1012                 return -EINVAL;
1013
1014         status = acpi_get_data(handle, acpi_bus_data_handler, (void **)device);
1015         if (ACPI_FAILURE(status) || !*device) {
1016                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
1017                                   handle));
1018                 return -ENODEV;
1019         }
1020         return 0;
1021 }
1022 EXPORT_SYMBOL_GPL(acpi_bus_get_device);
1023
1024 int acpi_device_add(struct acpi_device *device,
1025                     void (*release)(struct device *))
1026 {
1027         int result;
1028         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
1029         int found = 0;
1030
1031         if (device->handle) {
1032                 acpi_status status;
1033
1034                 status = acpi_attach_data(device->handle, acpi_bus_data_handler,
1035                                           device);
1036                 if (ACPI_FAILURE(status)) {
1037                         acpi_handle_err(device->handle,
1038                                         "Unable to attach device data\n");
1039                         return -ENODEV;
1040                 }
1041         }
1042
1043         /*
1044          * Linkage
1045          * -------
1046          * Link this device to its parent and siblings.
1047          */
1048         INIT_LIST_HEAD(&device->children);
1049         INIT_LIST_HEAD(&device->node);
1050         INIT_LIST_HEAD(&device->wakeup_list);
1051         INIT_LIST_HEAD(&device->physical_node_list);
1052         mutex_init(&device->physical_node_lock);
1053         INIT_LIST_HEAD(&device->power_dependent);
1054
1055         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
1056         if (!new_bus_id) {
1057                 pr_err(PREFIX "Memory allocation error\n");
1058                 result = -ENOMEM;
1059                 goto err_detach;
1060         }
1061
1062         mutex_lock(&acpi_device_lock);
1063         /*
1064          * Find suitable bus_id and instance number in acpi_bus_id_list
1065          * If failed, create one and link it into acpi_bus_id_list
1066          */
1067         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
1068                 if (!strcmp(acpi_device_bus_id->bus_id,
1069                             acpi_device_hid(device))) {
1070                         acpi_device_bus_id->instance_no++;
1071                         found = 1;
1072                         kfree(new_bus_id);
1073                         break;
1074                 }
1075         }
1076         if (!found) {
1077                 acpi_device_bus_id = new_bus_id;
1078                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
1079                 acpi_device_bus_id->instance_no = 0;
1080                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
1081         }
1082         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
1083
1084         if (device->parent)
1085                 list_add_tail(&device->node, &device->parent->children);
1086
1087         if (device->wakeup.flags.valid)
1088                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
1089         mutex_unlock(&acpi_device_lock);
1090
1091         if (device->parent)
1092                 device->dev.parent = &device->parent->dev;
1093         device->dev.bus = &acpi_bus_type;
1094         device->dev.release = release;
1095         result = device_add(&device->dev);
1096         if (result) {
1097                 dev_err(&device->dev, "Error registering device\n");
1098                 goto err;
1099         }
1100
1101         result = acpi_device_setup_files(device);
1102         if (result)
1103                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
1104                        dev_name(&device->dev));
1105
1106         return 0;
1107
1108  err:
1109         mutex_lock(&acpi_device_lock);
1110         if (device->parent)
1111                 list_del(&device->node);
1112         list_del(&device->wakeup_list);
1113         mutex_unlock(&acpi_device_lock);
1114
1115  err_detach:
1116         acpi_detach_data(device->handle, acpi_bus_data_handler);
1117         return result;
1118 }
1119
1120 static void acpi_device_unregister(struct acpi_device *device)
1121 {
1122         mutex_lock(&acpi_device_lock);
1123         if (device->parent)
1124                 list_del(&device->node);
1125
1126         list_del(&device->wakeup_list);
1127         mutex_unlock(&acpi_device_lock);
1128
1129         acpi_detach_data(device->handle, acpi_bus_data_handler);
1130
1131         acpi_power_add_remove_device(device, false);
1132         acpi_device_remove_files(device);
1133         if (device->remove)
1134                 device->remove(device);
1135
1136         device_del(&device->dev);
1137         /*
1138          * Transition the device to D3cold to drop the reference counts of all
1139          * power resources the device depends on and turn off the ones that have
1140          * no more references.
1141          */
1142         acpi_device_set_power(device, ACPI_STATE_D3_COLD);
1143         device->handle = NULL;
1144         put_device(&device->dev);
1145 }
1146
1147 /* --------------------------------------------------------------------------
1148                                  Driver Management
1149    -------------------------------------------------------------------------- */
1150 /**
1151  * acpi_bus_register_driver - register a driver with the ACPI bus
1152  * @driver: driver being registered
1153  *
1154  * Registers a driver with the ACPI bus.  Searches the namespace for all
1155  * devices that match the driver's criteria and binds.  Returns zero for
1156  * success or a negative error status for failure.
1157  */
1158 int acpi_bus_register_driver(struct acpi_driver *driver)
1159 {
1160         int ret;
1161
1162         if (acpi_disabled)
1163                 return -ENODEV;
1164         driver->drv.name = driver->name;
1165         driver->drv.bus = &acpi_bus_type;
1166         driver->drv.owner = driver->owner;
1167
1168         ret = driver_register(&driver->drv);
1169         return ret;
1170 }
1171
1172 EXPORT_SYMBOL(acpi_bus_register_driver);
1173
1174 /**
1175  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
1176  * @driver: driver to unregister
1177  *
1178  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
1179  * devices that match the driver's criteria and unbinds.
1180  */
1181 void acpi_bus_unregister_driver(struct acpi_driver *driver)
1182 {
1183         driver_unregister(&driver->drv);
1184 }
1185
1186 EXPORT_SYMBOL(acpi_bus_unregister_driver);
1187
1188 /* --------------------------------------------------------------------------
1189                                  Device Enumeration
1190    -------------------------------------------------------------------------- */
1191 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
1192 {
1193         struct acpi_device *device = NULL;
1194         acpi_status status;
1195
1196         /*
1197          * Fixed hardware devices do not appear in the namespace and do not
1198          * have handles, but we fabricate acpi_devices for them, so we have
1199          * to deal with them specially.
1200          */
1201         if (!handle)
1202                 return acpi_root;
1203
1204         do {
1205                 status = acpi_get_parent(handle, &handle);
1206                 if (ACPI_FAILURE(status))
1207                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
1208         } while (acpi_bus_get_device(handle, &device));
1209         return device;
1210 }
1211
1212 acpi_status
1213 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
1214 {
1215         acpi_status status;
1216         acpi_handle tmp;
1217         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
1218         union acpi_object *obj;
1219
1220         status = acpi_get_handle(handle, "_EJD", &tmp);
1221         if (ACPI_FAILURE(status))
1222                 return status;
1223
1224         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
1225         if (ACPI_SUCCESS(status)) {
1226                 obj = buffer.pointer;
1227                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
1228                                          ejd);
1229                 kfree(buffer.pointer);
1230         }
1231         return status;
1232 }
1233 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
1234
1235 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
1236                                         struct acpi_device_wakeup *wakeup)
1237 {
1238         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1239         union acpi_object *package = NULL;
1240         union acpi_object *element = NULL;
1241         acpi_status status;
1242         int err = -ENODATA;
1243
1244         if (!wakeup)
1245                 return -EINVAL;
1246
1247         INIT_LIST_HEAD(&wakeup->resources);
1248
1249         /* _PRW */
1250         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
1251         if (ACPI_FAILURE(status)) {
1252                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
1253                 return err;
1254         }
1255
1256         package = (union acpi_object *)buffer.pointer;
1257
1258         if (!package || package->package.count < 2)
1259                 goto out;
1260
1261         element = &(package->package.elements[0]);
1262         if (!element)
1263                 goto out;
1264
1265         if (element->type == ACPI_TYPE_PACKAGE) {
1266                 if ((element->package.count < 2) ||
1267                     (element->package.elements[0].type !=
1268                      ACPI_TYPE_LOCAL_REFERENCE)
1269                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
1270                         goto out;
1271
1272                 wakeup->gpe_device =
1273                     element->package.elements[0].reference.handle;
1274                 wakeup->gpe_number =
1275                     (u32) element->package.elements[1].integer.value;
1276         } else if (element->type == ACPI_TYPE_INTEGER) {
1277                 wakeup->gpe_device = NULL;
1278                 wakeup->gpe_number = element->integer.value;
1279         } else {
1280                 goto out;
1281         }
1282
1283         element = &(package->package.elements[1]);
1284         if (element->type != ACPI_TYPE_INTEGER)
1285                 goto out;
1286
1287         wakeup->sleep_state = element->integer.value;
1288
1289         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
1290         if (err)
1291                 goto out;
1292
1293         if (!list_empty(&wakeup->resources)) {
1294                 int sleep_state;
1295
1296                 err = acpi_power_wakeup_list_init(&wakeup->resources,
1297                                                   &sleep_state);
1298                 if (err) {
1299                         acpi_handle_warn(handle, "Retrieving current states "
1300                                          "of wakeup power resources failed\n");
1301                         acpi_power_resources_list_free(&wakeup->resources);
1302                         goto out;
1303                 }
1304                 if (sleep_state < wakeup->sleep_state) {
1305                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
1306                                          "(S%d) by S%d from power resources\n",
1307                                          (int)wakeup->sleep_state, sleep_state);
1308                         wakeup->sleep_state = sleep_state;
1309                 }
1310         }
1311         acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
1312
1313  out:
1314         kfree(buffer.pointer);
1315         return err;
1316 }
1317
1318 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
1319 {
1320         struct acpi_device_id button_device_ids[] = {
1321                 {"PNP0C0C", 0},
1322                 {"PNP0C0D", 0},
1323                 {"PNP0C0E", 0},
1324                 {"", 0},
1325         };
1326         acpi_status status;
1327         acpi_event_status event_status;
1328
1329         device->wakeup.flags.notifier_present = 0;
1330
1331         /* Power button, Lid switch always enable wakeup */
1332         if (!acpi_match_device_ids(device, button_device_ids)) {
1333                 device->wakeup.flags.run_wake = 1;
1334                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
1335                         /* Do not use Lid/sleep button for S5 wakeup */
1336                         if (device->wakeup.sleep_state == ACPI_STATE_S5)
1337                                 device->wakeup.sleep_state = ACPI_STATE_S4;
1338                 }
1339                 device_set_wakeup_capable(&device->dev, true);
1340                 return;
1341         }
1342
1343         status = acpi_get_gpe_status(device->wakeup.gpe_device,
1344                                         device->wakeup.gpe_number,
1345                                                 &event_status);
1346         if (status == AE_OK)
1347                 device->wakeup.flags.run_wake =
1348                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
1349 }
1350
1351 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1352 {
1353         acpi_handle temp;
1354         acpi_status status = 0;
1355         int err;
1356
1357         /* Presence of _PRW indicates wake capable */
1358         status = acpi_get_handle(device->handle, "_PRW", &temp);
1359         if (ACPI_FAILURE(status))
1360                 return;
1361
1362         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
1363                                                            &device->wakeup);
1364         if (err) {
1365                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
1366                 return;
1367         }
1368
1369         device->wakeup.flags.valid = 1;
1370         device->wakeup.prepare_count = 0;
1371         acpi_bus_set_run_wake_flags(device);
1372         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
1373          * system for the ACPI device with the _PRW object.
1374          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
1375          * So it is necessary to call _DSW object first. Only when it is not
1376          * present will the _PSW object used.
1377          */
1378         err = acpi_device_sleep_wake(device, 0, 0, 0);
1379         if (err)
1380                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1381                                 "error in _DSW or _PSW evaluation\n"));
1382 }
1383
1384 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1385 {
1386         struct acpi_device_power_state *ps = &device->power.states[state];
1387         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1388         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1389         acpi_handle handle;
1390         acpi_status status;
1391
1392         INIT_LIST_HEAD(&ps->resources);
1393
1394         /* Evaluate "_PRx" to get referenced power resources */
1395         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1396         if (ACPI_SUCCESS(status)) {
1397                 union acpi_object *package = buffer.pointer;
1398
1399                 if (buffer.length && package
1400                     && package->type == ACPI_TYPE_PACKAGE
1401                     && package->package.count) {
1402                         int err = acpi_extract_power_resources(package, 0,
1403                                                                &ps->resources);
1404                         if (!err)
1405                                 device->power.flags.power_resources = 1;
1406                 }
1407                 ACPI_FREE(buffer.pointer);
1408         }
1409
1410         /* Evaluate "_PSx" to see if we can do explicit sets */
1411         pathname[2] = 'S';
1412         status = acpi_get_handle(device->handle, pathname, &handle);
1413         if (ACPI_SUCCESS(status))
1414                 ps->flags.explicit_set = 1;
1415
1416         /*
1417          * State is valid if there are means to put the device into it.
1418          * D3hot is only valid if _PR3 present.
1419          */
1420         if (!list_empty(&ps->resources)
1421             || (ps->flags.explicit_set && state < ACPI_STATE_D3_HOT)) {
1422                 ps->flags.valid = 1;
1423                 ps->flags.os_accessible = 1;
1424         }
1425
1426         ps->power = -1;         /* Unknown - driver assigned */
1427         ps->latency = -1;       /* Unknown - driver assigned */
1428 }
1429
1430 static void acpi_bus_get_power_flags(struct acpi_device *device)
1431 {
1432         acpi_status status;
1433         acpi_handle handle;
1434         u32 i;
1435
1436         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1437         status = acpi_get_handle(device->handle, "_PS0", &handle);
1438         if (ACPI_FAILURE(status)) {
1439                 status = acpi_get_handle(device->handle, "_PR0", &handle);
1440                 if (ACPI_FAILURE(status))
1441                         return;
1442         }
1443
1444         device->flags.power_manageable = 1;
1445
1446         /*
1447          * Power Management Flags
1448          */
1449         status = acpi_get_handle(device->handle, "_PSC", &handle);
1450         if (ACPI_SUCCESS(status))
1451                 device->power.flags.explicit_get = 1;
1452         status = acpi_get_handle(device->handle, "_IRC", &handle);
1453         if (ACPI_SUCCESS(status))
1454                 device->power.flags.inrush_current = 1;
1455
1456         /*
1457          * Enumerate supported power management states
1458          */
1459         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1460                 acpi_bus_init_power_state(device, i);
1461
1462         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1463
1464         /* Set defaults for D0 and D3 states (always valid) */
1465         device->power.states[ACPI_STATE_D0].flags.valid = 1;
1466         device->power.states[ACPI_STATE_D0].power = 100;
1467         device->power.states[ACPI_STATE_D3].flags.valid = 1;
1468         device->power.states[ACPI_STATE_D3].power = 0;
1469
1470         /* Set D3cold's explicit_set flag if _PS3 exists. */
1471         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
1472                 device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
1473
1474         /* Presence of _PS3 or _PRx means we can put the device into D3 cold */
1475         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set ||
1476                         device->power.flags.power_resources)
1477                 device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
1478
1479         if (acpi_bus_init_power(device)) {
1480                 acpi_free_power_resources_lists(device);
1481                 device->flags.power_manageable = 0;
1482         }
1483 }
1484
1485 static void acpi_bus_get_flags(struct acpi_device *device)
1486 {
1487         acpi_status status = AE_OK;
1488         acpi_handle temp = NULL;
1489
1490         /* Presence of _STA indicates 'dynamic_status' */
1491         status = acpi_get_handle(device->handle, "_STA", &temp);
1492         if (ACPI_SUCCESS(status))
1493                 device->flags.dynamic_status = 1;
1494
1495         /* Presence of _RMV indicates 'removable' */
1496         status = acpi_get_handle(device->handle, "_RMV", &temp);
1497         if (ACPI_SUCCESS(status))
1498                 device->flags.removable = 1;
1499
1500         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1501         status = acpi_get_handle(device->handle, "_EJD", &temp);
1502         if (ACPI_SUCCESS(status))
1503                 device->flags.ejectable = 1;
1504         else {
1505                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
1506                 if (ACPI_SUCCESS(status))
1507                         device->flags.ejectable = 1;
1508         }
1509 }
1510
1511 static void acpi_device_get_busid(struct acpi_device *device)
1512 {
1513         char bus_id[5] = { '?', 0 };
1514         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1515         int i = 0;
1516
1517         /*
1518          * Bus ID
1519          * ------
1520          * The device's Bus ID is simply the object name.
1521          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1522          */
1523         if (ACPI_IS_ROOT_DEVICE(device)) {
1524                 strcpy(device->pnp.bus_id, "ACPI");
1525                 return;
1526         }
1527
1528         switch (device->device_type) {
1529         case ACPI_BUS_TYPE_POWER_BUTTON:
1530                 strcpy(device->pnp.bus_id, "PWRF");
1531                 break;
1532         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1533                 strcpy(device->pnp.bus_id, "SLPF");
1534                 break;
1535         default:
1536                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1537                 /* Clean up trailing underscores (if any) */
1538                 for (i = 3; i > 1; i--) {
1539                         if (bus_id[i] == '_')
1540                                 bus_id[i] = '\0';
1541                         else
1542                                 break;
1543                 }
1544                 strcpy(device->pnp.bus_id, bus_id);
1545                 break;
1546         }
1547 }
1548
1549 /*
1550  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1551  *
1552  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1553  * then we can safely call it an ejectable drive bay
1554  */
1555 static int acpi_bay_match(acpi_handle handle)
1556 {
1557         acpi_status status;
1558         acpi_handle tmp;
1559         acpi_handle phandle;
1560
1561         status = acpi_get_handle(handle, "_EJ0", &tmp);
1562         if (ACPI_FAILURE(status))
1563                 return -ENODEV;
1564
1565         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
1566                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
1567                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
1568                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
1569                 return 0;
1570
1571         if (acpi_get_parent(handle, &phandle))
1572                 return -ENODEV;
1573
1574         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
1575                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
1576                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
1577                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
1578                 return 0;
1579
1580         return -ENODEV;
1581 }
1582
1583 /*
1584  * acpi_dock_match - see if an acpi object has a _DCK method
1585  */
1586 static int acpi_dock_match(acpi_handle handle)
1587 {
1588         acpi_handle tmp;
1589         return acpi_get_handle(handle, "_DCK", &tmp);
1590 }
1591
1592 const char *acpi_device_hid(struct acpi_device *device)
1593 {
1594         struct acpi_hardware_id *hid;
1595
1596         if (list_empty(&device->pnp.ids))
1597                 return dummy_hid;
1598
1599         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1600         return hid->id;
1601 }
1602 EXPORT_SYMBOL(acpi_device_hid);
1603
1604 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1605 {
1606         struct acpi_hardware_id *id;
1607
1608         id = kmalloc(sizeof(*id), GFP_KERNEL);
1609         if (!id)
1610                 return;
1611
1612         id->id = kstrdup(dev_id, GFP_KERNEL);
1613         if (!id->id) {
1614                 kfree(id);
1615                 return;
1616         }
1617
1618         list_add_tail(&id->list, &pnp->ids);
1619         pnp->type.hardware_id = 1;
1620 }
1621
1622 /*
1623  * Old IBM workstations have a DSDT bug wherein the SMBus object
1624  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1625  * prefix.  Work around this.
1626  */
1627 static int acpi_ibm_smbus_match(acpi_handle handle)
1628 {
1629         acpi_handle h_dummy;
1630         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1631         int result;
1632
1633         if (!dmi_name_in_vendors("IBM"))
1634                 return -ENODEV;
1635
1636         /* Look for SMBS object */
1637         result = acpi_get_name(handle, ACPI_SINGLE_NAME, &path);
1638         if (result)
1639                 return result;
1640
1641         if (strcmp("SMBS", path.pointer)) {
1642                 result = -ENODEV;
1643                 goto out;
1644         }
1645
1646         /* Does it have the necessary (but misnamed) methods? */
1647         result = -ENODEV;
1648         if (ACPI_SUCCESS(acpi_get_handle(handle, "SBI", &h_dummy)) &&
1649             ACPI_SUCCESS(acpi_get_handle(handle, "SBR", &h_dummy)) &&
1650             ACPI_SUCCESS(acpi_get_handle(handle, "SBW", &h_dummy)))
1651                 result = 0;
1652 out:
1653         kfree(path.pointer);
1654         return result;
1655 }
1656
1657 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1658                                 int device_type)
1659 {
1660         acpi_status status;
1661         struct acpi_device_info *info;
1662         struct acpi_pnp_device_id_list *cid_list;
1663         int i;
1664
1665         switch (device_type) {
1666         case ACPI_BUS_TYPE_DEVICE:
1667                 if (handle == ACPI_ROOT_OBJECT) {
1668                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1669                         break;
1670                 }
1671
1672                 status = acpi_get_object_info(handle, &info);
1673                 if (ACPI_FAILURE(status)) {
1674                         pr_err(PREFIX "%s: Error reading device info\n",
1675                                         __func__);
1676                         return;
1677                 }
1678
1679                 if (info->valid & ACPI_VALID_HID)
1680                         acpi_add_id(pnp, info->hardware_id.string);
1681                 if (info->valid & ACPI_VALID_CID) {
1682                         cid_list = &info->compatible_id_list;
1683                         for (i = 0; i < cid_list->count; i++)
1684                                 acpi_add_id(pnp, cid_list->ids[i].string);
1685                 }
1686                 if (info->valid & ACPI_VALID_ADR) {
1687                         pnp->bus_address = info->address;
1688                         pnp->type.bus_address = 1;
1689                 }
1690                 if (info->valid & ACPI_VALID_UID)
1691                         pnp->unique_id = kstrdup(info->unique_id.string,
1692                                                         GFP_KERNEL);
1693
1694                 kfree(info);
1695
1696                 /*
1697                  * Some devices don't reliably have _HIDs & _CIDs, so add
1698                  * synthetic HIDs to make sure drivers can find them.
1699                  */
1700                 if (acpi_is_video_device(handle))
1701                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1702                 else if (ACPI_SUCCESS(acpi_bay_match(handle)))
1703                         acpi_add_id(pnp, ACPI_BAY_HID);
1704                 else if (ACPI_SUCCESS(acpi_dock_match(handle)))
1705                         acpi_add_id(pnp, ACPI_DOCK_HID);
1706                 else if (!acpi_ibm_smbus_match(handle))
1707                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1708                 else if (list_empty(&pnp->ids) && handle == ACPI_ROOT_OBJECT) {
1709                         acpi_add_id(pnp, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1710                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1711                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1712                 }
1713
1714                 break;
1715         case ACPI_BUS_TYPE_POWER:
1716                 acpi_add_id(pnp, ACPI_POWER_HID);
1717                 break;
1718         case ACPI_BUS_TYPE_PROCESSOR:
1719                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1720                 break;
1721         case ACPI_BUS_TYPE_THERMAL:
1722                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1723                 break;
1724         case ACPI_BUS_TYPE_POWER_BUTTON:
1725                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1726                 break;
1727         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1728                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1729                 break;
1730         }
1731 }
1732
1733 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1734 {
1735         struct acpi_hardware_id *id, *tmp;
1736
1737         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1738                 kfree(id->id);
1739                 kfree(id);
1740         }
1741         kfree(pnp->unique_id);
1742 }
1743
1744 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1745                              int type, unsigned long long sta)
1746 {
1747         INIT_LIST_HEAD(&device->pnp.ids);
1748         device->device_type = type;
1749         device->handle = handle;
1750         device->parent = acpi_bus_get_parent(handle);
1751         STRUCT_TO_INT(device->status) = sta;
1752         acpi_device_get_busid(device);
1753         acpi_set_pnp_ids(handle, &device->pnp, type);
1754         acpi_bus_get_flags(device);
1755         device->flags.match_driver = false;
1756         device_initialize(&device->dev);
1757         dev_set_uevent_suppress(&device->dev, true);
1758 }
1759
1760 void acpi_device_add_finalize(struct acpi_device *device)
1761 {
1762         device->flags.match_driver = true;
1763         dev_set_uevent_suppress(&device->dev, false);
1764         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1765 }
1766
1767 static int acpi_add_single_object(struct acpi_device **child,
1768                                   acpi_handle handle, int type,
1769                                   unsigned long long sta)
1770 {
1771         int result;
1772         struct acpi_device *device;
1773         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1774
1775         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1776         if (!device) {
1777                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1778                 return -ENOMEM;
1779         }
1780
1781         acpi_init_device_object(device, handle, type, sta);
1782         acpi_bus_get_power_flags(device);
1783         acpi_bus_get_wakeup_device_flags(device);
1784
1785         result = acpi_device_add(device, acpi_device_release);
1786         if (result) {
1787                 acpi_device_release(&device->dev);
1788                 return result;
1789         }
1790
1791         acpi_power_add_remove_device(device, true);
1792         acpi_device_add_finalize(device);
1793         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1794         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1795                 dev_name(&device->dev), (char *) buffer.pointer,
1796                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1797         kfree(buffer.pointer);
1798         *child = device;
1799         return 0;
1800 }
1801
1802 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1803                                     unsigned long long *sta)
1804 {
1805         acpi_status status;
1806         acpi_object_type acpi_type;
1807
1808         status = acpi_get_type(handle, &acpi_type);
1809         if (ACPI_FAILURE(status))
1810                 return -ENODEV;
1811
1812         switch (acpi_type) {
1813         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1814         case ACPI_TYPE_DEVICE:
1815                 *type = ACPI_BUS_TYPE_DEVICE;
1816                 status = acpi_bus_get_status_handle(handle, sta);
1817                 if (ACPI_FAILURE(status))
1818                         return -ENODEV;
1819                 break;
1820         case ACPI_TYPE_PROCESSOR:
1821                 *type = ACPI_BUS_TYPE_PROCESSOR;
1822                 status = acpi_bus_get_status_handle(handle, sta);
1823                 if (ACPI_FAILURE(status))
1824                         return -ENODEV;
1825                 break;
1826         case ACPI_TYPE_THERMAL:
1827                 *type = ACPI_BUS_TYPE_THERMAL;
1828                 *sta = ACPI_STA_DEFAULT;
1829                 break;
1830         case ACPI_TYPE_POWER:
1831                 *type = ACPI_BUS_TYPE_POWER;
1832                 *sta = ACPI_STA_DEFAULT;
1833                 break;
1834         default:
1835                 return -ENODEV;
1836         }
1837
1838         return 0;
1839 }
1840
1841 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1842                                        char *idstr,
1843                                        const struct acpi_device_id **matchid)
1844 {
1845         const struct acpi_device_id *devid;
1846
1847         for (devid = handler->ids; devid->id[0]; devid++)
1848                 if (!strcmp((char *)devid->id, idstr)) {
1849                         if (matchid)
1850                                 *matchid = devid;
1851
1852                         return true;
1853                 }
1854
1855         return false;
1856 }
1857
1858 static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr,
1859                                         const struct acpi_device_id **matchid)
1860 {
1861         struct acpi_scan_handler *handler;
1862
1863         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1864                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1865                         return handler;
1866
1867         return NULL;
1868 }
1869
1870 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1871 {
1872         if (!!hotplug->enabled == !!val)
1873                 return;
1874
1875         mutex_lock(&acpi_scan_lock);
1876
1877         hotplug->enabled = val;
1878
1879         mutex_unlock(&acpi_scan_lock);
1880 }
1881
1882 static void acpi_scan_init_hotplug(acpi_handle handle, int type)
1883 {
1884         struct acpi_device_pnp pnp = {};
1885         struct acpi_hardware_id *hwid;
1886         struct acpi_scan_handler *handler;
1887
1888         INIT_LIST_HEAD(&pnp.ids);
1889         acpi_set_pnp_ids(handle, &pnp, type);
1890
1891         if (!pnp.type.hardware_id)
1892                 goto out;
1893
1894         /*
1895          * This relies on the fact that acpi_install_notify_handler() will not
1896          * install the same notify handler routine twice for the same handle.
1897          */
1898         list_for_each_entry(hwid, &pnp.ids, list) {
1899                 handler = acpi_scan_match_handler(hwid->id, NULL);
1900                 if (handler) {
1901                         acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
1902                                         acpi_hotplug_notify_cb, handler);
1903                         break;
1904                 }
1905         }
1906
1907 out:
1908         acpi_free_pnp_ids(&pnp);
1909 }
1910
1911 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1912                                       void *not_used, void **return_value)
1913 {
1914         struct acpi_device *device = NULL;
1915         int type;
1916         unsigned long long sta;
1917         acpi_status status;
1918         int result;
1919
1920         acpi_bus_get_device(handle, &device);
1921         if (device)
1922                 goto out;
1923
1924         result = acpi_bus_type_and_status(handle, &type, &sta);
1925         if (result)
1926                 return AE_OK;
1927
1928         if (type == ACPI_BUS_TYPE_POWER) {
1929                 acpi_add_power_resource(handle);
1930                 return AE_OK;
1931         }
1932
1933         acpi_scan_init_hotplug(handle, type);
1934
1935         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1936             !(sta & ACPI_STA_DEVICE_FUNCTIONING)) {
1937                 struct acpi_device_wakeup wakeup;
1938                 acpi_handle temp;
1939
1940                 status = acpi_get_handle(handle, "_PRW", &temp);
1941                 if (ACPI_SUCCESS(status)) {
1942                         acpi_bus_extract_wakeup_device_power_package(handle,
1943                                                                      &wakeup);
1944                         acpi_power_resources_list_free(&wakeup.resources);
1945                 }
1946                 return AE_CTRL_DEPTH;
1947         }
1948
1949         acpi_add_single_object(&device, handle, type, sta);
1950         if (!device)
1951                 return AE_CTRL_DEPTH;
1952
1953  out:
1954         if (!*return_value)
1955                 *return_value = device;
1956
1957         return AE_OK;
1958 }
1959
1960 static int acpi_scan_attach_handler(struct acpi_device *device)
1961 {
1962         struct acpi_hardware_id *hwid;
1963         int ret = 0;
1964
1965         list_for_each_entry(hwid, &device->pnp.ids, list) {
1966                 const struct acpi_device_id *devid;
1967                 struct acpi_scan_handler *handler;
1968
1969                 handler = acpi_scan_match_handler(hwid->id, &devid);
1970                 if (handler) {
1971                         ret = handler->attach(device, devid);
1972                         if (ret > 0) {
1973                                 device->handler = handler;
1974                                 break;
1975                         } else if (ret < 0) {
1976                                 break;
1977                         }
1978                 }
1979         }
1980         return ret;
1981 }
1982
1983 static acpi_status acpi_bus_device_attach(acpi_handle handle, u32 lvl_not_used,
1984                                           void *not_used, void **ret_not_used)
1985 {
1986         struct acpi_device *device;
1987         unsigned long long sta_not_used;
1988         int ret;
1989
1990         /*
1991          * Ignore errors ignored by acpi_bus_check_add() to avoid terminating
1992          * namespace walks prematurely.
1993          */
1994         if (acpi_bus_type_and_status(handle, &ret, &sta_not_used))
1995                 return AE_OK;
1996
1997         if (acpi_bus_get_device(handle, &device))
1998                 return AE_CTRL_DEPTH;
1999
2000         if (device->handler)
2001                 return AE_OK;
2002
2003         ret = acpi_scan_attach_handler(device);
2004         if (ret)
2005                 return ret > 0 ? AE_OK : AE_CTRL_DEPTH;
2006
2007         ret = device_attach(&device->dev);
2008         return ret >= 0 ? AE_OK : AE_CTRL_DEPTH;
2009 }
2010
2011 /**
2012  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2013  * @handle: Root of the namespace scope to scan.
2014  *
2015  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2016  * found devices.
2017  *
2018  * If no devices were found, -ENODEV is returned, but it does not mean that
2019  * there has been a real error.  There just have been no suitable ACPI objects
2020  * in the table trunk from which the kernel could create a device and add an
2021  * appropriate driver.
2022  *
2023  * Must be called under acpi_scan_lock.
2024  */
2025 int acpi_bus_scan(acpi_handle handle)
2026 {
2027         void *device = NULL;
2028         int error = 0;
2029
2030         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
2031                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2032                                     acpi_bus_check_add, NULL, NULL, &device);
2033
2034         if (!device)
2035                 error = -ENODEV;
2036         else if (ACPI_SUCCESS(acpi_bus_device_attach(handle, 0, NULL, NULL)))
2037                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2038                                     acpi_bus_device_attach, NULL, NULL, NULL);
2039
2040         return error;
2041 }
2042 EXPORT_SYMBOL(acpi_bus_scan);
2043
2044 static acpi_status acpi_bus_device_detach(acpi_handle handle, u32 lvl_not_used,
2045                                           void *not_used, void **ret_not_used)
2046 {
2047         struct acpi_device *device = NULL;
2048
2049         if (!acpi_bus_get_device(handle, &device)) {
2050                 struct acpi_scan_handler *dev_handler = device->handler;
2051
2052                 if (dev_handler) {
2053                         if (dev_handler->detach)
2054                                 dev_handler->detach(device);
2055
2056                         device->handler = NULL;
2057                 } else {
2058                         device_release_driver(&device->dev);
2059                 }
2060         }
2061         return AE_OK;
2062 }
2063
2064 static acpi_status acpi_bus_remove(acpi_handle handle, u32 lvl_not_used,
2065                                    void *not_used, void **ret_not_used)
2066 {
2067         struct acpi_device *device = NULL;
2068
2069         if (!acpi_bus_get_device(handle, &device))
2070                 acpi_device_unregister(device);
2071
2072         return AE_OK;
2073 }
2074
2075 /**
2076  * acpi_bus_trim - Remove ACPI device node and all of its descendants
2077  * @start: Root of the ACPI device nodes subtree to remove.
2078  *
2079  * Must be called under acpi_scan_lock.
2080  */
2081 void acpi_bus_trim(struct acpi_device *start)
2082 {
2083         /*
2084          * Execute acpi_bus_device_detach() as a post-order callback to detach
2085          * all ACPI drivers from the device nodes being removed.
2086          */
2087         acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
2088                             acpi_bus_device_detach, NULL, NULL);
2089         acpi_bus_device_detach(start->handle, 0, NULL, NULL);
2090         /*
2091          * Execute acpi_bus_remove() as a post-order callback to remove device
2092          * nodes in the given namespace scope.
2093          */
2094         acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
2095                             acpi_bus_remove, NULL, NULL);
2096         acpi_bus_remove(start->handle, 0, NULL, NULL);
2097 }
2098 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2099
2100 static int acpi_bus_scan_fixed(void)
2101 {
2102         int result = 0;
2103
2104         /*
2105          * Enumerate all fixed-feature devices.
2106          */
2107         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2108                 struct acpi_device *device = NULL;
2109
2110                 result = acpi_add_single_object(&device, NULL,
2111                                                 ACPI_BUS_TYPE_POWER_BUTTON,
2112                                                 ACPI_STA_DEFAULT);
2113                 if (result)
2114                         return result;
2115
2116                 result = device_attach(&device->dev);
2117                 if (result < 0)
2118                         return result;
2119
2120                 device_init_wakeup(&device->dev, true);
2121         }
2122
2123         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2124                 struct acpi_device *device = NULL;
2125
2126                 result = acpi_add_single_object(&device, NULL,
2127                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2128                                                 ACPI_STA_DEFAULT);
2129                 if (result)
2130                         return result;
2131
2132                 result = device_attach(&device->dev);
2133         }
2134
2135         return result < 0 ? result : 0;
2136 }
2137
2138 int __init acpi_scan_init(void)
2139 {
2140         int result;
2141
2142         result = bus_register(&acpi_bus_type);
2143         if (result) {
2144                 /* We don't want to quit even if we failed to add suspend/resume */
2145                 printk(KERN_ERR PREFIX "Could not register bus type\n");
2146         }
2147
2148         acpi_pci_root_init();
2149         acpi_pci_link_init();
2150         acpi_processor_init();
2151         acpi_platform_init();
2152         acpi_lpss_init();
2153         acpi_cmos_rtc_init();
2154         acpi_container_init();
2155         acpi_memory_hotplug_init();
2156         acpi_dock_init();
2157
2158         mutex_lock(&acpi_scan_lock);
2159         /*
2160          * Enumerate devices in the ACPI namespace.
2161          */
2162         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2163         if (result)
2164                 goto out;
2165
2166         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2167         if (result)
2168                 goto out;
2169
2170         result = acpi_bus_scan_fixed();
2171         if (result) {
2172                 acpi_device_unregister(acpi_root);
2173                 goto out;
2174         }
2175
2176         acpi_update_all_gpes();
2177
2178         acpi_pci_root_hp_init();
2179
2180  out:
2181         mutex_unlock(&acpi_scan_lock);
2182         return result;
2183 }