linux/drivers/acpi/scan.c
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   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/acpi_iort.h>
  11#include <linux/signal.h>
  12#include <linux/kthread.h>
  13#include <linux/dmi.h>
  14#include <linux/nls.h>
  15#include <linux/dma-mapping.h>
  16#include <linux/platform_data/x86/apple.h>
  17
  18#include <asm/pgtable.h>
  19
  20#include "internal.h"
  21
  22#define _COMPONENT              ACPI_BUS_COMPONENT
  23ACPI_MODULE_NAME("scan");
  24extern struct acpi_device *acpi_root;
  25
  26#define ACPI_BUS_CLASS                  "system_bus"
  27#define ACPI_BUS_HID                    "LNXSYBUS"
  28#define ACPI_BUS_DEVICE_NAME            "System Bus"
  29
  30#define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
  31
  32#define INVALID_ACPI_HANDLE     ((acpi_handle)empty_zero_page)
  33
  34static const char *dummy_hid = "device";
  35
  36static LIST_HEAD(acpi_dep_list);
  37static DEFINE_MUTEX(acpi_dep_list_lock);
  38LIST_HEAD(acpi_bus_id_list);
  39static DEFINE_MUTEX(acpi_scan_lock);
  40static LIST_HEAD(acpi_scan_handlers_list);
  41DEFINE_MUTEX(acpi_device_lock);
  42LIST_HEAD(acpi_wakeup_device_list);
  43static DEFINE_MUTEX(acpi_hp_context_lock);
  44
  45/*
  46 * The UART device described by the SPCR table is the only object which needs
  47 * special-casing. Everything else is covered by ACPI namespace paths in STAO
  48 * table.
  49 */
  50static u64 spcr_uart_addr;
  51
  52struct acpi_dep_data {
  53        struct list_head node;
  54        acpi_handle master;
  55        acpi_handle slave;
  56};
  57
  58void acpi_scan_lock_acquire(void)
  59{
  60        mutex_lock(&acpi_scan_lock);
  61}
  62EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
  63
  64void acpi_scan_lock_release(void)
  65{
  66        mutex_unlock(&acpi_scan_lock);
  67}
  68EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
  69
  70void acpi_lock_hp_context(void)
  71{
  72        mutex_lock(&acpi_hp_context_lock);
  73}
  74
  75void acpi_unlock_hp_context(void)
  76{
  77        mutex_unlock(&acpi_hp_context_lock);
  78}
  79
  80void acpi_initialize_hp_context(struct acpi_device *adev,
  81                                struct acpi_hotplug_context *hp,
  82                                int (*notify)(struct acpi_device *, u32),
  83                                void (*uevent)(struct acpi_device *, u32))
  84{
  85        acpi_lock_hp_context();
  86        hp->notify = notify;
  87        hp->uevent = uevent;
  88        acpi_set_hp_context(adev, hp);
  89        acpi_unlock_hp_context();
  90}
  91EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
  92
  93int acpi_scan_add_handler(struct acpi_scan_handler *handler)
  94{
  95        if (!handler)
  96                return -EINVAL;
  97
  98        list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
  99        return 0;
 100}
 101
 102int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
 103                                       const char *hotplug_profile_name)
 104{
 105        int error;
 106
 107        error = acpi_scan_add_handler(handler);
 108        if (error)
 109                return error;
 110
 111        acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
 112        return 0;
 113}
 114
 115bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
 116{
 117        struct acpi_device_physical_node *pn;
 118        bool offline = true;
 119        char *envp[] = { "EVENT=offline", NULL };
 120
 121        /*
 122         * acpi_container_offline() calls this for all of the container's
 123         * children under the container's physical_node_lock lock.
 124         */
 125        mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
 126
 127        list_for_each_entry(pn, &adev->physical_node_list, node)
 128                if (device_supports_offline(pn->dev) && !pn->dev->offline) {
 129                        if (uevent)
 130                                kobject_uevent_env(&pn->dev->kobj, KOBJ_CHANGE, envp);
 131
 132                        offline = false;
 133                        break;
 134                }
 135
 136        mutex_unlock(&adev->physical_node_lock);
 137        return offline;
 138}
 139
 140static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
 141                                    void **ret_p)
 142{
 143        struct acpi_device *device = NULL;
 144        struct acpi_device_physical_node *pn;
 145        bool second_pass = (bool)data;
 146        acpi_status status = AE_OK;
 147
 148        if (acpi_bus_get_device(handle, &device))
 149                return AE_OK;
 150
 151        if (device->handler && !device->handler->hotplug.enabled) {
 152                *ret_p = &device->dev;
 153                return AE_SUPPORT;
 154        }
 155
 156        mutex_lock(&device->physical_node_lock);
 157
 158        list_for_each_entry(pn, &device->physical_node_list, node) {
 159                int ret;
 160
 161                if (second_pass) {
 162                        /* Skip devices offlined by the first pass. */
 163                        if (pn->put_online)
 164                                continue;
 165                } else {
 166                        pn->put_online = false;
 167                }
 168                ret = device_offline(pn->dev);
 169                if (ret >= 0) {
 170                        pn->put_online = !ret;
 171                } else {
 172                        *ret_p = pn->dev;
 173                        if (second_pass) {
 174                                status = AE_ERROR;
 175                                break;
 176                        }
 177                }
 178        }
 179
 180        mutex_unlock(&device->physical_node_lock);
 181
 182        return status;
 183}
 184
 185static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
 186                                   void **ret_p)
 187{
 188        struct acpi_device *device = NULL;
 189        struct acpi_device_physical_node *pn;
 190
 191        if (acpi_bus_get_device(handle, &device))
 192                return AE_OK;
 193
 194        mutex_lock(&device->physical_node_lock);
 195
 196        list_for_each_entry(pn, &device->physical_node_list, node)
 197                if (pn->put_online) {
 198                        device_online(pn->dev);
 199                        pn->put_online = false;
 200                }
 201
 202        mutex_unlock(&device->physical_node_lock);
 203
 204        return AE_OK;
 205}
 206
 207static int acpi_scan_try_to_offline(struct acpi_device *device)
 208{
 209        acpi_handle handle = device->handle;
 210        struct device *errdev = NULL;
 211        acpi_status status;
 212
 213        /*
 214         * Carry out two passes here and ignore errors in the first pass,
 215         * because if the devices in question are memory blocks and
 216         * CONFIG_MEMCG is set, one of the blocks may hold data structures
 217         * that the other blocks depend on, but it is not known in advance which
 218         * block holds them.
 219         *
 220         * If the first pass is successful, the second one isn't needed, though.
 221         */
 222        status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 223                                     NULL, acpi_bus_offline, (void *)false,
 224                                     (void **)&errdev);
 225        if (status == AE_SUPPORT) {
 226                dev_warn(errdev, "Offline disabled.\n");
 227                acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 228                                    acpi_bus_online, NULL, NULL, NULL);
 229                return -EPERM;
 230        }
 231        acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
 232        if (errdev) {
 233                errdev = NULL;
 234                acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 235                                    NULL, acpi_bus_offline, (void *)true,
 236                                    (void **)&errdev);
 237                if (!errdev)
 238                        acpi_bus_offline(handle, 0, (void *)true,
 239                                         (void **)&errdev);
 240
 241                if (errdev) {
 242                        dev_warn(errdev, "Offline failed.\n");
 243                        acpi_bus_online(handle, 0, NULL, NULL);
 244                        acpi_walk_namespace(ACPI_TYPE_ANY, handle,
 245                                            ACPI_UINT32_MAX, acpi_bus_online,
 246                                            NULL, NULL, NULL);
 247                        return -EBUSY;
 248                }
 249        }
 250        return 0;
 251}
 252
 253static int acpi_scan_hot_remove(struct acpi_device *device)
 254{
 255        acpi_handle handle = device->handle;
 256        unsigned long long sta;
 257        acpi_status status;
 258
 259        if (device->handler && device->handler->hotplug.demand_offline) {
 260                if (!acpi_scan_is_offline(device, true))
 261                        return -EBUSY;
 262        } else {
 263                int error = acpi_scan_try_to_offline(device);
 264                if (error)
 265                        return error;
 266        }
 267
 268        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 269                "Hot-removing device %s...\n", dev_name(&device->dev)));
 270
 271        acpi_bus_trim(device);
 272
 273        acpi_evaluate_lck(handle, 0);
 274        /*
 275         * TBD: _EJD support.
 276         */
 277        status = acpi_evaluate_ej0(handle);
 278        if (status == AE_NOT_FOUND)
 279                return -ENODEV;
 280        else if (ACPI_FAILURE(status))
 281                return -EIO;
 282
 283        /*
 284         * Verify if eject was indeed successful.  If not, log an error
 285         * message.  No need to call _OST since _EJ0 call was made OK.
 286         */
 287        status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 288        if (ACPI_FAILURE(status)) {
 289                acpi_handle_warn(handle,
 290                        "Status check after eject failed (0x%x)\n", status);
 291        } else if (sta & ACPI_STA_DEVICE_ENABLED) {
 292                acpi_handle_warn(handle,
 293                        "Eject incomplete - status 0x%llx\n", sta);
 294        }
 295
 296        return 0;
 297}
 298
 299static int acpi_scan_device_not_present(struct acpi_device *adev)
 300{
 301        if (!acpi_device_enumerated(adev)) {
 302                dev_warn(&adev->dev, "Still not present\n");
 303                return -EALREADY;
 304        }
 305        acpi_bus_trim(adev);
 306        return 0;
 307}
 308
 309static int acpi_scan_device_check(struct acpi_device *adev)
 310{
 311        int error;
 312
 313        acpi_bus_get_status(adev);
 314        if (adev->status.present || adev->status.functional) {
 315                /*
 316                 * This function is only called for device objects for which
 317                 * matching scan handlers exist.  The only situation in which
 318                 * the scan handler is not attached to this device object yet
 319                 * is when the device has just appeared (either it wasn't
 320                 * present at all before or it was removed and then added
 321                 * again).
 322                 */
 323                if (adev->handler) {
 324                        dev_warn(&adev->dev, "Already enumerated\n");
 325                        return -EALREADY;
 326                }
 327                error = acpi_bus_scan(adev->handle);
 328                if (error) {
 329                        dev_warn(&adev->dev, "Namespace scan failure\n");
 330                        return error;
 331                }
 332                if (!adev->handler) {
 333                        dev_warn(&adev->dev, "Enumeration failure\n");
 334                        error = -ENODEV;
 335                }
 336        } else {
 337                error = acpi_scan_device_not_present(adev);
 338        }
 339        return error;
 340}
 341
 342static int acpi_scan_bus_check(struct acpi_device *adev)
 343{
 344        struct acpi_scan_handler *handler = adev->handler;
 345        struct acpi_device *child;
 346        int error;
 347
 348        acpi_bus_get_status(adev);
 349        if (!(adev->status.present || adev->status.functional)) {
 350                acpi_scan_device_not_present(adev);
 351                return 0;
 352        }
 353        if (handler && handler->hotplug.scan_dependent)
 354                return handler->hotplug.scan_dependent(adev);
 355
 356        error = acpi_bus_scan(adev->handle);
 357        if (error) {
 358                dev_warn(&adev->dev, "Namespace scan failure\n");
 359                return error;
 360        }
 361        list_for_each_entry(child, &adev->children, node) {
 362                error = acpi_scan_bus_check(child);
 363                if (error)
 364                        return error;
 365        }
 366        return 0;
 367}
 368
 369static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
 370{
 371        switch (type) {
 372        case ACPI_NOTIFY_BUS_CHECK:
 373                return acpi_scan_bus_check(adev);
 374        case ACPI_NOTIFY_DEVICE_CHECK:
 375                return acpi_scan_device_check(adev);
 376        case ACPI_NOTIFY_EJECT_REQUEST:
 377        case ACPI_OST_EC_OSPM_EJECT:
 378                if (adev->handler && !adev->handler->hotplug.enabled) {
 379                        dev_info(&adev->dev, "Eject disabled\n");
 380                        return -EPERM;
 381                }
 382                acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
 383                                  ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 384                return acpi_scan_hot_remove(adev);
 385        }
 386        return -EINVAL;
 387}
 388
 389void acpi_device_hotplug(struct acpi_device *adev, u32 src)
 390{
 391        u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 392        int error = -ENODEV;
 393
 394        lock_device_hotplug();
 395        mutex_lock(&acpi_scan_lock);
 396
 397        /*
 398         * The device object's ACPI handle cannot become invalid as long as we
 399         * are holding acpi_scan_lock, but it might have become invalid before
 400         * that lock was acquired.
 401         */
 402        if (adev->handle == INVALID_ACPI_HANDLE)
 403                goto err_out;
 404
 405        if (adev->flags.is_dock_station) {
 406                error = dock_notify(adev, src);
 407        } else if (adev->flags.hotplug_notify) {
 408                error = acpi_generic_hotplug_event(adev, src);
 409        } else {
 410                int (*notify)(struct acpi_device *, u32);
 411
 412                acpi_lock_hp_context();
 413                notify = adev->hp ? adev->hp->notify : NULL;
 414                acpi_unlock_hp_context();
 415                /*
 416                 * There may be additional notify handlers for device objects
 417                 * without the .event() callback, so ignore them here.
 418                 */
 419                if (notify)
 420                        error = notify(adev, src);
 421                else
 422                        goto out;
 423        }
 424        switch (error) {
 425        case 0:
 426                ost_code = ACPI_OST_SC_SUCCESS;
 427                break;
 428        case -EPERM:
 429                ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 430                break;
 431        case -EBUSY:
 432                ost_code = ACPI_OST_SC_DEVICE_BUSY;
 433                break;
 434        default:
 435                ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 436                break;
 437        }
 438
 439 err_out:
 440        acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
 441
 442 out:
 443        acpi_bus_put_acpi_device(adev);
 444        mutex_unlock(&acpi_scan_lock);
 445        unlock_device_hotplug();
 446}
 447
 448static void acpi_free_power_resources_lists(struct acpi_device *device)
 449{
 450        int i;
 451
 452        if (device->wakeup.flags.valid)
 453                acpi_power_resources_list_free(&device->wakeup.resources);
 454
 455        if (!device->power.flags.power_resources)
 456                return;
 457
 458        for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 459                struct acpi_device_power_state *ps = &device->power.states[i];
 460                acpi_power_resources_list_free(&ps->resources);
 461        }
 462}
 463
 464static void acpi_device_release(struct device *dev)
 465{
 466        struct acpi_device *acpi_dev = to_acpi_device(dev);
 467
 468        acpi_free_properties(acpi_dev);
 469        acpi_free_pnp_ids(&acpi_dev->pnp);
 470        acpi_free_power_resources_lists(acpi_dev);
 471        kfree(acpi_dev);
 472}
 473
 474static void acpi_device_del(struct acpi_device *device)
 475{
 476        struct acpi_device_bus_id *acpi_device_bus_id;
 477
 478        mutex_lock(&acpi_device_lock);
 479        if (device->parent)
 480                list_del(&device->node);
 481
 482        list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
 483                if (!strcmp(acpi_device_bus_id->bus_id,
 484                            acpi_device_hid(device))) {
 485                        if (acpi_device_bus_id->instance_no > 0)
 486                                acpi_device_bus_id->instance_no--;
 487                        else {
 488                                list_del(&acpi_device_bus_id->node);
 489                                kfree(acpi_device_bus_id);
 490                        }
 491                        break;
 492                }
 493
 494        list_del(&device->wakeup_list);
 495        mutex_unlock(&acpi_device_lock);
 496
 497        acpi_power_add_remove_device(device, false);
 498        acpi_device_remove_files(device);
 499        if (device->remove)
 500                device->remove(device);
 501
 502        device_del(&device->dev);
 503}
 504
 505static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
 506
 507static LIST_HEAD(acpi_device_del_list);
 508static DEFINE_MUTEX(acpi_device_del_lock);
 509
 510static void acpi_device_del_work_fn(struct work_struct *work_not_used)
 511{
 512        for (;;) {
 513                struct acpi_device *adev;
 514
 515                mutex_lock(&acpi_device_del_lock);
 516
 517                if (list_empty(&acpi_device_del_list)) {
 518                        mutex_unlock(&acpi_device_del_lock);
 519                        break;
 520                }
 521                adev = list_first_entry(&acpi_device_del_list,
 522                                        struct acpi_device, del_list);
 523                list_del(&adev->del_list);
 524
 525                mutex_unlock(&acpi_device_del_lock);
 526
 527                blocking_notifier_call_chain(&acpi_reconfig_chain,
 528                                             ACPI_RECONFIG_DEVICE_REMOVE, adev);
 529
 530                acpi_device_del(adev);
 531                /*
 532                 * Drop references to all power resources that might have been
 533                 * used by the device.
 534                 */
 535                acpi_power_transition(adev, ACPI_STATE_D3_COLD);
 536                put_device(&adev->dev);
 537        }
 538}
 539
 540/**
 541 * acpi_scan_drop_device - Drop an ACPI device object.
 542 * @handle: Handle of an ACPI namespace node, not used.
 543 * @context: Address of the ACPI device object to drop.
 544 *
 545 * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
 546 * namespace node the device object pointed to by @context is attached to.
 547 *
 548 * The unregistration is carried out asynchronously to avoid running
 549 * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
 550 * ensure the correct ordering (the device objects must be unregistered in the
 551 * same order in which the corresponding namespace nodes are deleted).
 552 */
 553static void acpi_scan_drop_device(acpi_handle handle, void *context)
 554{
 555        static DECLARE_WORK(work, acpi_device_del_work_fn);
 556        struct acpi_device *adev = context;
 557
 558        mutex_lock(&acpi_device_del_lock);
 559
 560        /*
 561         * Use the ACPI hotplug workqueue which is ordered, so this work item
 562         * won't run after any hotplug work items submitted subsequently.  That
 563         * prevents attempts to register device objects identical to those being
 564         * deleted from happening concurrently (such attempts result from
 565         * hotplug events handled via the ACPI hotplug workqueue).  It also will
 566         * run after all of the work items submitted previosuly, which helps
 567         * those work items to ensure that they are not accessing stale device
 568         * objects.
 569         */
 570        if (list_empty(&acpi_device_del_list))
 571                acpi_queue_hotplug_work(&work);
 572
 573        list_add_tail(&adev->del_list, &acpi_device_del_list);
 574        /* Make acpi_ns_validate_handle() return NULL for this handle. */
 575        adev->handle = INVALID_ACPI_HANDLE;
 576
 577        mutex_unlock(&acpi_device_del_lock);
 578}
 579
 580static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
 581                                void (*callback)(void *))
 582{
 583        acpi_status status;
 584
 585        if (!device)
 586                return -EINVAL;
 587
 588        status = acpi_get_data_full(handle, acpi_scan_drop_device,
 589                                    (void **)device, callback);
 590        if (ACPI_FAILURE(status) || !*device) {
 591                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
 592                                  handle));
 593                return -ENODEV;
 594        }
 595        return 0;
 596}
 597
 598int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
 599{
 600        return acpi_get_device_data(handle, device, NULL);
 601}
 602EXPORT_SYMBOL(acpi_bus_get_device);
 603
 604static void get_acpi_device(void *dev)
 605{
 606        if (dev)
 607                get_device(&((struct acpi_device *)dev)->dev);
 608}
 609
 610struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
 611{
 612        struct acpi_device *adev = NULL;
 613
 614        acpi_get_device_data(handle, &adev, get_acpi_device);
 615        return adev;
 616}
 617
 618void acpi_bus_put_acpi_device(struct acpi_device *adev)
 619{
 620        put_device(&adev->dev);
 621}
 622
 623int acpi_device_add(struct acpi_device *device,
 624                    void (*release)(struct device *))
 625{
 626        int result;
 627        struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 628        int found = 0;
 629
 630        if (device->handle) {
 631                acpi_status status;
 632
 633                status = acpi_attach_data(device->handle, acpi_scan_drop_device,
 634                                          device);
 635                if (ACPI_FAILURE(status)) {
 636                        acpi_handle_err(device->handle,
 637                                        "Unable to attach device data\n");
 638                        return -ENODEV;
 639                }
 640        }
 641
 642        /*
 643         * Linkage
 644         * -------
 645         * Link this device to its parent and siblings.
 646         */
 647        INIT_LIST_HEAD(&device->children);
 648        INIT_LIST_HEAD(&device->node);
 649        INIT_LIST_HEAD(&device->wakeup_list);
 650        INIT_LIST_HEAD(&device->physical_node_list);
 651        INIT_LIST_HEAD(&device->del_list);
 652        mutex_init(&device->physical_node_lock);
 653
 654        new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 655        if (!new_bus_id) {
 656                pr_err(PREFIX "Memory allocation error\n");
 657                result = -ENOMEM;
 658                goto err_detach;
 659        }
 660
 661        mutex_lock(&acpi_device_lock);
 662        /*
 663         * Find suitable bus_id and instance number in acpi_bus_id_list
 664         * If failed, create one and link it into acpi_bus_id_list
 665         */
 666        list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 667                if (!strcmp(acpi_device_bus_id->bus_id,
 668                            acpi_device_hid(device))) {
 669                        acpi_device_bus_id->instance_no++;
 670                        found = 1;
 671                        kfree(new_bus_id);
 672                        break;
 673                }
 674        }
 675        if (!found) {
 676                acpi_device_bus_id = new_bus_id;
 677                strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
 678                acpi_device_bus_id->instance_no = 0;
 679                list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 680        }
 681        dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 682
 683        if (device->parent)
 684                list_add_tail(&device->node, &device->parent->children);
 685
 686        if (device->wakeup.flags.valid)
 687                list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 688        mutex_unlock(&acpi_device_lock);
 689
 690        if (device->parent)
 691                device->dev.parent = &device->parent->dev;
 692        device->dev.bus = &acpi_bus_type;
 693        device->dev.release = release;
 694        result = device_add(&device->dev);
 695        if (result) {
 696                dev_err(&device->dev, "Error registering device\n");
 697                goto err;
 698        }
 699
 700        result = acpi_device_setup_files(device);
 701        if (result)
 702                printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 703                       dev_name(&device->dev));
 704
 705        return 0;
 706
 707 err:
 708        mutex_lock(&acpi_device_lock);
 709        if (device->parent)
 710                list_del(&device->node);
 711        list_del(&device->wakeup_list);
 712        mutex_unlock(&acpi_device_lock);
 713
 714 err_detach:
 715        acpi_detach_data(device->handle, acpi_scan_drop_device);
 716        return result;
 717}
 718
 719/* --------------------------------------------------------------------------
 720                                 Device Enumeration
 721   -------------------------------------------------------------------------- */
 722static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
 723{
 724        struct acpi_device *device = NULL;
 725        acpi_status status;
 726
 727        /*
 728         * Fixed hardware devices do not appear in the namespace and do not
 729         * have handles, but we fabricate acpi_devices for them, so we have
 730         * to deal with them specially.
 731         */
 732        if (!handle)
 733                return acpi_root;
 734
 735        do {
 736                status = acpi_get_parent(handle, &handle);
 737                if (ACPI_FAILURE(status))
 738                        return status == AE_NULL_ENTRY ? NULL : acpi_root;
 739        } while (acpi_bus_get_device(handle, &device));
 740        return device;
 741}
 742
 743acpi_status
 744acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 745{
 746        acpi_status status;
 747        acpi_handle tmp;
 748        struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 749        union acpi_object *obj;
 750
 751        status = acpi_get_handle(handle, "_EJD", &tmp);
 752        if (ACPI_FAILURE(status))
 753                return status;
 754
 755        status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 756        if (ACPI_SUCCESS(status)) {
 757                obj = buffer.pointer;
 758                status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 759                                         ejd);
 760                kfree(buffer.pointer);
 761        }
 762        return status;
 763}
 764EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 765
 766static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
 767                                        struct acpi_device_wakeup *wakeup)
 768{
 769        struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 770        union acpi_object *package = NULL;
 771        union acpi_object *element = NULL;
 772        acpi_status status;
 773        int err = -ENODATA;
 774
 775        if (!wakeup)
 776                return -EINVAL;
 777
 778        INIT_LIST_HEAD(&wakeup->resources);
 779
 780        /* _PRW */
 781        status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
 782        if (ACPI_FAILURE(status)) {
 783                ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 784                return err;
 785        }
 786
 787        package = (union acpi_object *)buffer.pointer;
 788
 789        if (!package || package->package.count < 2)
 790                goto out;
 791
 792        element = &(package->package.elements[0]);
 793        if (!element)
 794                goto out;
 795
 796        if (element->type == ACPI_TYPE_PACKAGE) {
 797                if ((element->package.count < 2) ||
 798                    (element->package.elements[0].type !=
 799                     ACPI_TYPE_LOCAL_REFERENCE)
 800                    || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 801                        goto out;
 802
 803                wakeup->gpe_device =
 804                    element->package.elements[0].reference.handle;
 805                wakeup->gpe_number =
 806                    (u32) element->package.elements[1].integer.value;
 807        } else if (element->type == ACPI_TYPE_INTEGER) {
 808                wakeup->gpe_device = NULL;
 809                wakeup->gpe_number = element->integer.value;
 810        } else {
 811                goto out;
 812        }
 813
 814        element = &(package->package.elements[1]);
 815        if (element->type != ACPI_TYPE_INTEGER)
 816                goto out;
 817
 818        wakeup->sleep_state = element->integer.value;
 819
 820        err = acpi_extract_power_resources(package, 2, &wakeup->resources);
 821        if (err)
 822                goto out;
 823
 824        if (!list_empty(&wakeup->resources)) {
 825                int sleep_state;
 826
 827                err = acpi_power_wakeup_list_init(&wakeup->resources,
 828                                                  &sleep_state);
 829                if (err) {
 830                        acpi_handle_warn(handle, "Retrieving current states "
 831                                         "of wakeup power resources failed\n");
 832                        acpi_power_resources_list_free(&wakeup->resources);
 833                        goto out;
 834                }
 835                if (sleep_state < wakeup->sleep_state) {
 836                        acpi_handle_warn(handle, "Overriding _PRW sleep state "
 837                                         "(S%d) by S%d from power resources\n",
 838                                         (int)wakeup->sleep_state, sleep_state);
 839                        wakeup->sleep_state = sleep_state;
 840                }
 841        }
 842
 843 out:
 844        kfree(buffer.pointer);
 845        return err;
 846}
 847
 848static bool acpi_wakeup_gpe_init(struct acpi_device *device)
 849{
 850        static const struct acpi_device_id button_device_ids[] = {
 851                {"PNP0C0C", 0},
 852                {"PNP0C0D", 0},
 853                {"PNP0C0E", 0},
 854                {"", 0},
 855        };
 856        struct acpi_device_wakeup *wakeup = &device->wakeup;
 857        acpi_status status;
 858
 859        wakeup->flags.notifier_present = 0;
 860
 861        /* Power button, Lid switch always enable wakeup */
 862        if (!acpi_match_device_ids(device, button_device_ids)) {
 863                if (!acpi_match_device_ids(device, &button_device_ids[1])) {
 864                        /* Do not use Lid/sleep button for S5 wakeup */
 865                        if (wakeup->sleep_state == ACPI_STATE_S5)
 866                                wakeup->sleep_state = ACPI_STATE_S4;
 867                }
 868                acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
 869                device_set_wakeup_capable(&device->dev, true);
 870                return true;
 871        }
 872
 873        status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
 874                                         wakeup->gpe_number);
 875        return ACPI_SUCCESS(status);
 876}
 877
 878static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 879{
 880        int err;
 881
 882        /* Presence of _PRW indicates wake capable */
 883        if (!acpi_has_method(device->handle, "_PRW"))
 884                return;
 885
 886        err = acpi_bus_extract_wakeup_device_power_package(device->handle,
 887                                                           &device->wakeup);
 888        if (err) {
 889                dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
 890                return;
 891        }
 892
 893        device->wakeup.flags.valid = acpi_wakeup_gpe_init(device);
 894        device->wakeup.prepare_count = 0;
 895        /*
 896         * Call _PSW/_DSW object to disable its ability to wake the sleeping
 897         * system for the ACPI device with the _PRW object.
 898         * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 899         * So it is necessary to call _DSW object first. Only when it is not
 900         * present will the _PSW object used.
 901         */
 902        err = acpi_device_sleep_wake(device, 0, 0, 0);
 903        if (err)
 904                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 905                                "error in _DSW or _PSW evaluation\n"));
 906}
 907
 908static void acpi_bus_init_power_state(struct acpi_device *device, int state)
 909{
 910        struct acpi_device_power_state *ps = &device->power.states[state];
 911        char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
 912        struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 913        acpi_status status;
 914
 915        INIT_LIST_HEAD(&ps->resources);
 916
 917        /* Evaluate "_PRx" to get referenced power resources */
 918        status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
 919        if (ACPI_SUCCESS(status)) {
 920                union acpi_object *package = buffer.pointer;
 921
 922                if (buffer.length && package
 923                    && package->type == ACPI_TYPE_PACKAGE
 924                    && package->package.count) {
 925                        int err = acpi_extract_power_resources(package, 0,
 926                                                               &ps->resources);
 927                        if (!err)
 928                                device->power.flags.power_resources = 1;
 929                }
 930                ACPI_FREE(buffer.pointer);
 931        }
 932
 933        /* Evaluate "_PSx" to see if we can do explicit sets */
 934        pathname[2] = 'S';
 935        if (acpi_has_method(device->handle, pathname))
 936                ps->flags.explicit_set = 1;
 937
 938        /* State is valid if there are means to put the device into it. */
 939        if (!list_empty(&ps->resources) || ps->flags.explicit_set)
 940                ps->flags.valid = 1;
 941
 942        ps->power = -1;         /* Unknown - driver assigned */
 943        ps->latency = -1;       /* Unknown - driver assigned */
 944}
 945
 946static void acpi_bus_get_power_flags(struct acpi_device *device)
 947{
 948        u32 i;
 949
 950        /* Presence of _PS0|_PR0 indicates 'power manageable' */
 951        if (!acpi_has_method(device->handle, "_PS0") &&
 952            !acpi_has_method(device->handle, "_PR0"))
 953                return;
 954
 955        device->flags.power_manageable = 1;
 956
 957        /*
 958         * Power Management Flags
 959         */
 960        if (acpi_has_method(device->handle, "_PSC"))
 961                device->power.flags.explicit_get = 1;
 962
 963        if (acpi_has_method(device->handle, "_IRC"))
 964                device->power.flags.inrush_current = 1;
 965
 966        if (acpi_has_method(device->handle, "_DSW"))
 967                device->power.flags.dsw_present = 1;
 968
 969        /*
 970         * Enumerate supported power management states
 971         */
 972        for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
 973                acpi_bus_init_power_state(device, i);
 974
 975        INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
 976        if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
 977                device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
 978
 979        /* Set defaults for D0 and D3hot states (always valid) */
 980        device->power.states[ACPI_STATE_D0].flags.valid = 1;
 981        device->power.states[ACPI_STATE_D0].power = 100;
 982        device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
 983
 984        if (acpi_bus_init_power(device))
 985                device->flags.power_manageable = 0;
 986}
 987
 988static void acpi_bus_get_flags(struct acpi_device *device)
 989{
 990        /* Presence of _STA indicates 'dynamic_status' */
 991        if (acpi_has_method(device->handle, "_STA"))
 992                device->flags.dynamic_status = 1;
 993
 994        /* Presence of _RMV indicates 'removable' */
 995        if (acpi_has_method(device->handle, "_RMV"))
 996                device->flags.removable = 1;
 997
 998        /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 999        if (acpi_has_method(device->handle, "_EJD") ||
1000            acpi_has_method(device->handle, "_EJ0"))
1001                device->flags.ejectable = 1;
1002}
1003
1004static void acpi_device_get_busid(struct acpi_device *device)
1005{
1006        char bus_id[5] = { '?', 0 };
1007        struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1008        int i = 0;
1009
1010        /*
1011         * Bus ID
1012         * ------
1013         * The device's Bus ID is simply the object name.
1014         * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1015         */
1016        if (ACPI_IS_ROOT_DEVICE(device)) {
1017                strcpy(device->pnp.bus_id, "ACPI");
1018                return;
1019        }
1020
1021        switch (device->device_type) {
1022        case ACPI_BUS_TYPE_POWER_BUTTON:
1023                strcpy(device->pnp.bus_id, "PWRF");
1024                break;
1025        case ACPI_BUS_TYPE_SLEEP_BUTTON:
1026                strcpy(device->pnp.bus_id, "SLPF");
1027                break;
1028        case ACPI_BUS_TYPE_ECDT_EC:
1029                strcpy(device->pnp.bus_id, "ECDT");
1030                break;
1031        default:
1032                acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1033                /* Clean up trailing underscores (if any) */
1034                for (i = 3; i > 1; i--) {
1035                        if (bus_id[i] == '_')
1036                                bus_id[i] = '\0';
1037                        else
1038                                break;
1039                }
1040                strcpy(device->pnp.bus_id, bus_id);
1041                break;
1042        }
1043}
1044
1045/*
1046 * acpi_ata_match - see if an acpi object is an ATA device
1047 *
1048 * If an acpi object has one of the ACPI ATA methods defined,
1049 * then we can safely call it an ATA device.
1050 */
1051bool acpi_ata_match(acpi_handle handle)
1052{
1053        return acpi_has_method(handle, "_GTF") ||
1054               acpi_has_method(handle, "_GTM") ||
1055               acpi_has_method(handle, "_STM") ||
1056               acpi_has_method(handle, "_SDD");
1057}
1058
1059/*
1060 * acpi_bay_match - see if an acpi object is an ejectable driver bay
1061 *
1062 * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1063 * then we can safely call it an ejectable drive bay
1064 */
1065bool acpi_bay_match(acpi_handle handle)
1066{
1067        acpi_handle phandle;
1068
1069        if (!acpi_has_method(handle, "_EJ0"))
1070                return false;
1071        if (acpi_ata_match(handle))
1072                return true;
1073        if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1074                return false;
1075
1076        return acpi_ata_match(phandle);
1077}
1078
1079bool acpi_device_is_battery(struct acpi_device *adev)
1080{
1081        struct acpi_hardware_id *hwid;
1082
1083        list_for_each_entry(hwid, &adev->pnp.ids, list)
1084                if (!strcmp("PNP0C0A", hwid->id))
1085                        return true;
1086
1087        return false;
1088}
1089
1090static bool is_ejectable_bay(struct acpi_device *adev)
1091{
1092        acpi_handle handle = adev->handle;
1093
1094        if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1095                return true;
1096
1097        return acpi_bay_match(handle);
1098}
1099
1100/*
1101 * acpi_dock_match - see if an acpi object has a _DCK method
1102 */
1103bool acpi_dock_match(acpi_handle handle)
1104{
1105        return acpi_has_method(handle, "_DCK");
1106}
1107
1108static acpi_status
1109acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1110                          void **return_value)
1111{
1112        long *cap = context;
1113
1114        if (acpi_has_method(handle, "_BCM") &&
1115            acpi_has_method(handle, "_BCL")) {
1116                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
1117                                  "support\n"));
1118                *cap |= ACPI_VIDEO_BACKLIGHT;
1119                /* We have backlight support, no need to scan further */
1120                return AE_CTRL_TERMINATE;
1121        }
1122        return 0;
1123}
1124
1125/* Returns true if the ACPI object is a video device which can be
1126 * handled by video.ko.
1127 * The device will get a Linux specific CID added in scan.c to
1128 * identify the device as an ACPI graphics device
1129 * Be aware that the graphics device may not be physically present
1130 * Use acpi_video_get_capabilities() to detect general ACPI video
1131 * capabilities of present cards
1132 */
1133long acpi_is_video_device(acpi_handle handle)
1134{
1135        long video_caps = 0;
1136
1137        /* Is this device able to support video switching ? */
1138        if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1139                video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1140
1141        /* Is this device able to retrieve a video ROM ? */
1142        if (acpi_has_method(handle, "_ROM"))
1143                video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1144
1145        /* Is this device able to configure which video head to be POSTed ? */
1146        if (acpi_has_method(handle, "_VPO") &&
1147            acpi_has_method(handle, "_GPD") &&
1148            acpi_has_method(handle, "_SPD"))
1149                video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1150
1151        /* Only check for backlight functionality if one of the above hit. */
1152        if (video_caps)
1153                acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1154                                    ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1155                                    &video_caps, NULL);
1156
1157        return video_caps;
1158}
1159EXPORT_SYMBOL(acpi_is_video_device);
1160
1161const char *acpi_device_hid(struct acpi_device *device)
1162{
1163        struct acpi_hardware_id *hid;
1164
1165        if (list_empty(&device->pnp.ids))
1166                return dummy_hid;
1167
1168        hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1169        return hid->id;
1170}
1171EXPORT_SYMBOL(acpi_device_hid);
1172
1173static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1174{
1175        struct acpi_hardware_id *id;
1176
1177        id = kmalloc(sizeof(*id), GFP_KERNEL);
1178        if (!id)
1179                return;
1180
1181        id->id = kstrdup_const(dev_id, GFP_KERNEL);
1182        if (!id->id) {
1183                kfree(id);
1184                return;
1185        }
1186
1187        list_add_tail(&id->list, &pnp->ids);
1188        pnp->type.hardware_id = 1;
1189}
1190
1191/*
1192 * Old IBM workstations have a DSDT bug wherein the SMBus object
1193 * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1194 * prefix.  Work around this.
1195 */
1196static bool acpi_ibm_smbus_match(acpi_handle handle)
1197{
1198        char node_name[ACPI_PATH_SEGMENT_LENGTH];
1199        struct acpi_buffer path = { sizeof(node_name), node_name };
1200
1201        if (!dmi_name_in_vendors("IBM"))
1202                return false;
1203
1204        /* Look for SMBS object */
1205        if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1206            strcmp("SMBS", path.pointer))
1207                return false;
1208
1209        /* Does it have the necessary (but misnamed) methods? */
1210        if (acpi_has_method(handle, "SBI") &&
1211            acpi_has_method(handle, "SBR") &&
1212            acpi_has_method(handle, "SBW"))
1213                return true;
1214
1215        return false;
1216}
1217
1218static bool acpi_object_is_system_bus(acpi_handle handle)
1219{
1220        acpi_handle tmp;
1221
1222        if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1223            tmp == handle)
1224                return true;
1225        if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1226            tmp == handle)
1227                return true;
1228
1229        return false;
1230}
1231
1232static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1233                                int device_type)
1234{
1235        acpi_status status;
1236        struct acpi_device_info *info;
1237        struct acpi_pnp_device_id_list *cid_list;
1238        int i;
1239
1240        switch (device_type) {
1241        case ACPI_BUS_TYPE_DEVICE:
1242                if (handle == ACPI_ROOT_OBJECT) {
1243                        acpi_add_id(pnp, ACPI_SYSTEM_HID);
1244                        break;
1245                }
1246
1247                status = acpi_get_object_info(handle, &info);
1248                if (ACPI_FAILURE(status)) {
1249                        pr_err(PREFIX "%s: Error reading device info\n",
1250                                        __func__);
1251                        return;
1252                }
1253
1254                if (info->valid & ACPI_VALID_HID) {
1255                        acpi_add_id(pnp, info->hardware_id.string);
1256                        pnp->type.platform_id = 1;
1257                }
1258                if (info->valid & ACPI_VALID_CID) {
1259                        cid_list = &info->compatible_id_list;
1260                        for (i = 0; i < cid_list->count; i++)
1261                                acpi_add_id(pnp, cid_list->ids[i].string);
1262                }
1263                if (info->valid & ACPI_VALID_ADR) {
1264                        pnp->bus_address = info->address;
1265                        pnp->type.bus_address = 1;
1266                }
1267                if (info->valid & ACPI_VALID_UID)
1268                        pnp->unique_id = kstrdup(info->unique_id.string,
1269                                                        GFP_KERNEL);
1270                if (info->valid & ACPI_VALID_CLS)
1271                        acpi_add_id(pnp, info->class_code.string);
1272
1273                kfree(info);
1274
1275                /*
1276                 * Some devices don't reliably have _HIDs & _CIDs, so add
1277                 * synthetic HIDs to make sure drivers can find them.
1278                 */
1279                if (acpi_is_video_device(handle))
1280                        acpi_add_id(pnp, ACPI_VIDEO_HID);
1281                else if (acpi_bay_match(handle))
1282                        acpi_add_id(pnp, ACPI_BAY_HID);
1283                else if (acpi_dock_match(handle))
1284                        acpi_add_id(pnp, ACPI_DOCK_HID);
1285                else if (acpi_ibm_smbus_match(handle))
1286                        acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1287                else if (list_empty(&pnp->ids) &&
1288                         acpi_object_is_system_bus(handle)) {
1289                        /* \_SB, \_TZ, LNXSYBUS */
1290                        acpi_add_id(pnp, ACPI_BUS_HID);
1291                        strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1292                        strcpy(pnp->device_class, ACPI_BUS_CLASS);
1293                }
1294
1295                break;
1296        case ACPI_BUS_TYPE_POWER:
1297                acpi_add_id(pnp, ACPI_POWER_HID);
1298                break;
1299        case ACPI_BUS_TYPE_PROCESSOR:
1300                acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1301                break;
1302        case ACPI_BUS_TYPE_THERMAL:
1303                acpi_add_id(pnp, ACPI_THERMAL_HID);
1304                break;
1305        case ACPI_BUS_TYPE_POWER_BUTTON:
1306                acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1307                break;
1308        case ACPI_BUS_TYPE_SLEEP_BUTTON:
1309                acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1310                break;
1311        case ACPI_BUS_TYPE_ECDT_EC:
1312                acpi_add_id(pnp, ACPI_ECDT_HID);
1313                break;
1314        }
1315}
1316
1317void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1318{
1319        struct acpi_hardware_id *id, *tmp;
1320
1321        list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1322                kfree_const(id->id);
1323                kfree(id);
1324        }
1325        kfree(pnp->unique_id);
1326}
1327
1328/**
1329 * acpi_dma_supported - Check DMA support for the specified device.
1330 * @adev: The pointer to acpi device
1331 *
1332 * Return false if DMA is not supported. Otherwise, return true
1333 */
1334bool acpi_dma_supported(struct acpi_device *adev)
1335{
1336        if (!adev)
1337                return false;
1338
1339        if (adev->flags.cca_seen)
1340                return true;
1341
1342        /*
1343        * Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1344        * DMA on "Intel platforms".  Presumably that includes all x86 and
1345        * ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1346        */
1347        if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1348                return true;
1349
1350        return false;
1351}
1352
1353/**
1354 * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1355 * @adev: The pointer to acpi device
1356 *
1357 * Return enum dev_dma_attr.
1358 */
1359enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1360{
1361        if (!acpi_dma_supported(adev))
1362                return DEV_DMA_NOT_SUPPORTED;
1363
1364        if (adev->flags.coherent_dma)
1365                return DEV_DMA_COHERENT;
1366        else
1367                return DEV_DMA_NON_COHERENT;
1368}
1369
1370/**
1371 * acpi_dma_get_range() - Get device DMA parameters.
1372 *
1373 * @dev: device to configure
1374 * @dma_addr: pointer device DMA address result
1375 * @offset: pointer to the DMA offset result
1376 * @size: pointer to DMA range size result
1377 *
1378 * Evaluate DMA regions and return respectively DMA region start, offset
1379 * and size in dma_addr, offset and size on parsing success; it does not
1380 * update the passed in values on failure.
1381 *
1382 * Return 0 on success, < 0 on failure.
1383 */
1384int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
1385                       u64 *size)
1386{
1387        struct acpi_device *adev;
1388        LIST_HEAD(list);
1389        struct resource_entry *rentry;
1390        int ret;
1391        struct device *dma_dev = dev;
1392        u64 len, dma_start = U64_MAX, dma_end = 0, dma_offset = 0;
1393
1394        /*
1395         * Walk the device tree chasing an ACPI companion with a _DMA
1396         * object while we go. Stop if we find a device with an ACPI
1397         * companion containing a _DMA method.
1398         */
1399        do {
1400                adev = ACPI_COMPANION(dma_dev);
1401                if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA))
1402                        break;
1403
1404                dma_dev = dma_dev->parent;
1405        } while (dma_dev);
1406
1407        if (!dma_dev)
1408                return -ENODEV;
1409
1410        if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) {
1411                acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n");
1412                return -EINVAL;
1413        }
1414
1415        ret = acpi_dev_get_dma_resources(adev, &list);
1416        if (ret > 0) {
1417                list_for_each_entry(rentry, &list, node) {
1418                        if (dma_offset && rentry->offset != dma_offset) {
1419                                ret = -EINVAL;
1420                                dev_warn(dma_dev, "Can't handle multiple windows with different offsets\n");
1421                                goto out;
1422                        }
1423                        dma_offset = rentry->offset;
1424
1425                        /* Take lower and upper limits */
1426                        if (rentry->res->start < dma_start)
1427                                dma_start = rentry->res->start;
1428                        if (rentry->res->end > dma_end)
1429                                dma_end = rentry->res->end;
1430                }
1431
1432                if (dma_start >= dma_end) {
1433                        ret = -EINVAL;
1434                        dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
1435                        goto out;
1436                }
1437
1438                *dma_addr = dma_start - dma_offset;
1439                len = dma_end - dma_start;
1440                *size = max(len, len + 1);
1441                *offset = dma_offset;
1442        }
1443 out:
1444        acpi_dev_free_resource_list(&list);
1445
1446        return ret >= 0 ? 0 : ret;
1447}
1448
1449/**
1450 * acpi_dma_configure - Set-up DMA configuration for the device.
1451 * @dev: The pointer to the device
1452 * @attr: device dma attributes
1453 */
1454int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
1455{
1456        const struct iommu_ops *iommu;
1457        u64 dma_addr = 0, size = 0;
1458
1459        iort_dma_setup(dev, &dma_addr, &size);
1460
1461        iommu = iort_iommu_configure(dev);
1462        if (IS_ERR(iommu) && PTR_ERR(iommu) == -EPROBE_DEFER)
1463                return -EPROBE_DEFER;
1464
1465        arch_setup_dma_ops(dev, dma_addr, size,
1466                                iommu, attr == DEV_DMA_COHERENT);
1467
1468        return 0;
1469}
1470EXPORT_SYMBOL_GPL(acpi_dma_configure);
1471
1472/**
1473 * acpi_dma_deconfigure - Tear-down DMA configuration for the device.
1474 * @dev: The pointer to the device
1475 */
1476void acpi_dma_deconfigure(struct device *dev)
1477{
1478        arch_teardown_dma_ops(dev);
1479}
1480EXPORT_SYMBOL_GPL(acpi_dma_deconfigure);
1481
1482static void acpi_init_coherency(struct acpi_device *adev)
1483{
1484        unsigned long long cca = 0;
1485        acpi_status status;
1486        struct acpi_device *parent = adev->parent;
1487
1488        if (parent && parent->flags.cca_seen) {
1489                /*
1490                 * From ACPI spec, OSPM will ignore _CCA if an ancestor
1491                 * already saw one.
1492                 */
1493                adev->flags.cca_seen = 1;
1494                cca = parent->flags.coherent_dma;
1495        } else {
1496                status = acpi_evaluate_integer(adev->handle, "_CCA",
1497                                               NULL, &cca);
1498                if (ACPI_SUCCESS(status))
1499                        adev->flags.cca_seen = 1;
1500                else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1501                        /*
1502                         * If architecture does not specify that _CCA is
1503                         * required for DMA-able devices (e.g. x86),
1504                         * we default to _CCA=1.
1505                         */
1506                        cca = 1;
1507                else
1508                        acpi_handle_debug(adev->handle,
1509                                          "ACPI device is missing _CCA.\n");
1510        }
1511
1512        adev->flags.coherent_dma = cca;
1513}
1514
1515static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data)
1516{
1517        bool *is_serial_bus_slave_p = data;
1518
1519        if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1520                return 1;
1521
1522        *is_serial_bus_slave_p = true;
1523
1524         /* no need to do more checking */
1525        return -1;
1526}
1527
1528static bool acpi_is_indirect_io_slave(struct acpi_device *device)
1529{
1530        struct acpi_device *parent = device->parent;
1531        const struct acpi_device_id indirect_io_hosts[] = {
1532                {"HISI0191", 0},
1533                {}
1534        };
1535
1536        return parent && !acpi_match_device_ids(parent, indirect_io_hosts);
1537}
1538
1539static bool acpi_device_enumeration_by_parent(struct acpi_device *device)
1540{
1541        struct list_head resource_list;
1542        bool is_serial_bus_slave = false;
1543
1544        if (acpi_is_indirect_io_slave(device))
1545                return true;
1546
1547        /* Macs use device properties in lieu of _CRS resources */
1548        if (x86_apple_machine &&
1549            (fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
1550             fwnode_property_present(&device->fwnode, "i2cAddress") ||
1551             fwnode_property_present(&device->fwnode, "baud")))
1552                return true;
1553
1554        INIT_LIST_HEAD(&resource_list);
1555        acpi_dev_get_resources(device, &resource_list,
1556                               acpi_check_serial_bus_slave,
1557                               &is_serial_bus_slave);
1558        acpi_dev_free_resource_list(&resource_list);
1559
1560        return is_serial_bus_slave;
1561}
1562
1563void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1564                             int type, unsigned long long sta)
1565{
1566        INIT_LIST_HEAD(&device->pnp.ids);
1567        device->device_type = type;
1568        device->handle = handle;
1569        device->parent = acpi_bus_get_parent(handle);
1570        device->fwnode.ops = &acpi_device_fwnode_ops;
1571        acpi_set_device_status(device, sta);
1572        acpi_device_get_busid(device);
1573        acpi_set_pnp_ids(handle, &device->pnp, type);
1574        acpi_init_properties(device);
1575        acpi_bus_get_flags(device);
1576        device->flags.match_driver = false;
1577        device->flags.initialized = true;
1578        device->flags.enumeration_by_parent =
1579                acpi_device_enumeration_by_parent(device);
1580        acpi_device_clear_enumerated(device);
1581        device_initialize(&device->dev);
1582        dev_set_uevent_suppress(&device->dev, true);
1583        acpi_init_coherency(device);
1584        /* Assume there are unmet deps until acpi_device_dep_initialize() runs */
1585        device->dep_unmet = 1;
1586}
1587
1588void acpi_device_add_finalize(struct acpi_device *device)
1589{
1590        dev_set_uevent_suppress(&device->dev, false);
1591        kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1592}
1593
1594static int acpi_add_single_object(struct acpi_device **child,
1595                                  acpi_handle handle, int type,
1596                                  unsigned long long sta)
1597{
1598        int result;
1599        struct acpi_device *device;
1600        struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1601
1602        device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1603        if (!device) {
1604                printk(KERN_ERR PREFIX "Memory allocation error\n");
1605                return -ENOMEM;
1606        }
1607
1608        acpi_init_device_object(device, handle, type, sta);
1609        /*
1610         * For ACPI_BUS_TYPE_DEVICE getting the status is delayed till here so
1611         * that we can call acpi_bus_get_status() and use its quirk handling.
1612         * Note this must be done before the get power-/wakeup_dev-flags calls.
1613         */
1614        if (type == ACPI_BUS_TYPE_DEVICE)
1615                acpi_bus_get_status(device);
1616
1617        acpi_bus_get_power_flags(device);
1618        acpi_bus_get_wakeup_device_flags(device);
1619
1620        result = acpi_device_add(device, acpi_device_release);
1621        if (result) {
1622                acpi_device_release(&device->dev);
1623                return result;
1624        }
1625
1626        acpi_power_add_remove_device(device, true);
1627        acpi_device_add_finalize(device);
1628        acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1629        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1630                dev_name(&device->dev), (char *) buffer.pointer,
1631                device->parent ? dev_name(&device->parent->dev) : "(null)"));
1632        kfree(buffer.pointer);
1633        *child = device;
1634        return 0;
1635}
1636
1637static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1638                                            void *context)
1639{
1640        struct resource *res = context;
1641
1642        if (acpi_dev_resource_memory(ares, res))
1643                return AE_CTRL_TERMINATE;
1644
1645        return AE_OK;
1646}
1647
1648static bool acpi_device_should_be_hidden(acpi_handle handle)
1649{
1650        acpi_status status;
1651        struct resource res;
1652
1653        /* Check if it should ignore the UART device */
1654        if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1655                return false;
1656
1657        /*
1658         * The UART device described in SPCR table is assumed to have only one
1659         * memory resource present. So we only look for the first one here.
1660         */
1661        status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1662                                     acpi_get_resource_memory, &res);
1663        if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1664                return false;
1665
1666        acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1667                         &res.start);
1668
1669        return true;
1670}
1671
1672static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1673                                    unsigned long long *sta)
1674{
1675        acpi_status status;
1676        acpi_object_type acpi_type;
1677
1678        status = acpi_get_type(handle, &acpi_type);
1679        if (ACPI_FAILURE(status))
1680                return -ENODEV;
1681
1682        switch (acpi_type) {
1683        case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1684        case ACPI_TYPE_DEVICE:
1685                if (acpi_device_should_be_hidden(handle))
1686                        return -ENODEV;
1687
1688                *type = ACPI_BUS_TYPE_DEVICE;
1689                /*
1690                 * acpi_add_single_object updates this once we've an acpi_device
1691                 * so that acpi_bus_get_status' quirk handling can be used.
1692                 */
1693                *sta = 0;
1694                break;
1695        case ACPI_TYPE_PROCESSOR:
1696                *type = ACPI_BUS_TYPE_PROCESSOR;
1697                status = acpi_bus_get_status_handle(handle, sta);
1698                if (ACPI_FAILURE(status))
1699                        return -ENODEV;
1700                break;
1701        case ACPI_TYPE_THERMAL:
1702                *type = ACPI_BUS_TYPE_THERMAL;
1703                *sta = ACPI_STA_DEFAULT;
1704                break;
1705        case ACPI_TYPE_POWER:
1706                *type = ACPI_BUS_TYPE_POWER;
1707                *sta = ACPI_STA_DEFAULT;
1708                break;
1709        default:
1710                return -ENODEV;
1711        }
1712
1713        return 0;
1714}
1715
1716bool acpi_device_is_present(const struct acpi_device *adev)
1717{
1718        return adev->status.present || adev->status.functional;
1719}
1720
1721static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1722                                       const char *idstr,
1723                                       const struct acpi_device_id **matchid)
1724{
1725        const struct acpi_device_id *devid;
1726
1727        if (handler->match)
1728                return handler->match(idstr, matchid);
1729
1730        for (devid = handler->ids; devid->id[0]; devid++)
1731                if (!strcmp((char *)devid->id, idstr)) {
1732                        if (matchid)
1733                                *matchid = devid;
1734
1735                        return true;
1736                }
1737
1738        return false;
1739}
1740
1741static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1742                                        const struct acpi_device_id **matchid)
1743{
1744        struct acpi_scan_handler *handler;
1745
1746        list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1747                if (acpi_scan_handler_matching(handler, idstr, matchid))
1748                        return handler;
1749
1750        return NULL;
1751}
1752
1753void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1754{
1755        if (!!hotplug->enabled == !!val)
1756                return;
1757
1758        mutex_lock(&acpi_scan_lock);
1759
1760        hotplug->enabled = val;
1761
1762        mutex_unlock(&acpi_scan_lock);
1763}
1764
1765static void acpi_scan_init_hotplug(struct acpi_device *adev)
1766{
1767        struct acpi_hardware_id *hwid;
1768
1769        if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1770                acpi_dock_add(adev);
1771                return;
1772        }
1773        list_for_each_entry(hwid, &adev->pnp.ids, list) {
1774                struct acpi_scan_handler *handler;
1775
1776                handler = acpi_scan_match_handler(hwid->id, NULL);
1777                if (handler) {
1778                        adev->flags.hotplug_notify = true;
1779                        break;
1780                }
1781        }
1782}
1783
1784static void acpi_device_dep_initialize(struct acpi_device *adev)
1785{
1786        struct acpi_dep_data *dep;
1787        struct acpi_handle_list dep_devices;
1788        acpi_status status;
1789        int i;
1790
1791        adev->dep_unmet = 0;
1792
1793        if (!acpi_has_method(adev->handle, "_DEP"))
1794                return;
1795
1796        status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
1797                                        &dep_devices);
1798        if (ACPI_FAILURE(status)) {
1799                dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
1800                return;
1801        }
1802
1803        for (i = 0; i < dep_devices.count; i++) {
1804                struct acpi_device_info *info;
1805                int skip;
1806
1807                status = acpi_get_object_info(dep_devices.handles[i], &info);
1808                if (ACPI_FAILURE(status)) {
1809                        dev_dbg(&adev->dev, "Error reading _DEP device info\n");
1810                        continue;
1811                }
1812
1813                /*
1814                 * Skip the dependency of Windows System Power
1815                 * Management Controller
1816                 */
1817                skip = info->valid & ACPI_VALID_HID &&
1818                        !strcmp(info->hardware_id.string, "INT3396");
1819
1820                kfree(info);
1821
1822                if (skip)
1823                        continue;
1824
1825                dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
1826                if (!dep)
1827                        return;
1828
1829                dep->master = dep_devices.handles[i];
1830                dep->slave  = adev->handle;
1831                adev->dep_unmet++;
1832
1833                mutex_lock(&acpi_dep_list_lock);
1834                list_add_tail(&dep->node , &acpi_dep_list);
1835                mutex_unlock(&acpi_dep_list_lock);
1836        }
1837}
1838
1839static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1840                                      void *not_used, void **return_value)
1841{
1842        struct acpi_device *device = NULL;
1843        int type;
1844        unsigned long long sta;
1845        int result;
1846
1847        acpi_bus_get_device(handle, &device);
1848        if (device)
1849                goto out;
1850
1851        result = acpi_bus_type_and_status(handle, &type, &sta);
1852        if (result)
1853                return AE_OK;
1854
1855        if (type == ACPI_BUS_TYPE_POWER) {
1856                acpi_add_power_resource(handle);
1857                return AE_OK;
1858        }
1859
1860        acpi_add_single_object(&device, handle, type, sta);
1861        if (!device)
1862                return AE_CTRL_DEPTH;
1863
1864        acpi_scan_init_hotplug(device);
1865        acpi_device_dep_initialize(device);
1866
1867 out:
1868        if (!*return_value)
1869                *return_value = device;
1870
1871        return AE_OK;
1872}
1873
1874static void acpi_default_enumeration(struct acpi_device *device)
1875{
1876        /*
1877         * Do not enumerate devices with enumeration_by_parent flag set as
1878         * they will be enumerated by their respective parents.
1879         */
1880        if (!device->flags.enumeration_by_parent) {
1881                acpi_create_platform_device(device, NULL);
1882                acpi_device_set_enumerated(device);
1883        } else {
1884                blocking_notifier_call_chain(&acpi_reconfig_chain,
1885                                             ACPI_RECONFIG_DEVICE_ADD, device);
1886        }
1887}
1888
1889static const struct acpi_device_id generic_device_ids[] = {
1890        {ACPI_DT_NAMESPACE_HID, },
1891        {"", },
1892};
1893
1894static int acpi_generic_device_attach(struct acpi_device *adev,
1895                                      const struct acpi_device_id *not_used)
1896{
1897        /*
1898         * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
1899         * below can be unconditional.
1900         */
1901        if (adev->data.of_compatible)
1902                acpi_default_enumeration(adev);
1903
1904        return 1;
1905}
1906
1907static struct acpi_scan_handler generic_device_handler = {
1908        .ids = generic_device_ids,
1909        .attach = acpi_generic_device_attach,
1910};
1911
1912static int acpi_scan_attach_handler(struct acpi_device *device)
1913{
1914        struct acpi_hardware_id *hwid;
1915        int ret = 0;
1916
1917        list_for_each_entry(hwid, &device->pnp.ids, list) {
1918                const struct acpi_device_id *devid;
1919                struct acpi_scan_handler *handler;
1920
1921                handler = acpi_scan_match_handler(hwid->id, &devid);
1922                if (handler) {
1923                        if (!handler->attach) {
1924                                device->pnp.type.platform_id = 0;
1925                                continue;
1926                        }
1927                        device->handler = handler;
1928                        ret = handler->attach(device, devid);
1929                        if (ret > 0)
1930                                break;
1931
1932                        device->handler = NULL;
1933                        if (ret < 0)
1934                                break;
1935                }
1936        }
1937
1938        return ret;
1939}
1940
1941static void acpi_bus_attach(struct acpi_device *device)
1942{
1943        struct acpi_device *child;
1944        acpi_handle ejd;
1945        int ret;
1946
1947        if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
1948                register_dock_dependent_device(device, ejd);
1949
1950        acpi_bus_get_status(device);
1951        /* Skip devices that are not present. */
1952        if (!acpi_device_is_present(device)) {
1953                device->flags.initialized = false;
1954                acpi_device_clear_enumerated(device);
1955                device->flags.power_manageable = 0;
1956                return;
1957        }
1958        if (device->handler)
1959                goto ok;
1960
1961        if (!device->flags.initialized) {
1962                device->flags.power_manageable =
1963                        device->power.states[ACPI_STATE_D0].flags.valid;
1964                if (acpi_bus_init_power(device))
1965                        device->flags.power_manageable = 0;
1966
1967                device->flags.initialized = true;
1968        } else if (device->flags.visited) {
1969                goto ok;
1970        }
1971
1972        ret = acpi_scan_attach_handler(device);
1973        if (ret < 0)
1974                return;
1975
1976        device->flags.match_driver = true;
1977        if (ret > 0 && !device->flags.enumeration_by_parent) {
1978                acpi_device_set_enumerated(device);
1979                goto ok;
1980        }
1981
1982        ret = device_attach(&device->dev);
1983        if (ret < 0)
1984                return;
1985
1986        if (device->pnp.type.platform_id || device->flags.enumeration_by_parent)
1987                acpi_default_enumeration(device);
1988        else
1989                acpi_device_set_enumerated(device);
1990
1991 ok:
1992        list_for_each_entry(child, &device->children, node)
1993                acpi_bus_attach(child);
1994
1995        if (device->handler && device->handler->hotplug.notify_online)
1996                device->handler->hotplug.notify_online(device);
1997}
1998
1999void acpi_walk_dep_device_list(acpi_handle handle)
2000{
2001        struct acpi_dep_data *dep, *tmp;
2002        struct acpi_device *adev;
2003
2004        mutex_lock(&acpi_dep_list_lock);
2005        list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2006                if (dep->master == handle) {
2007                        acpi_bus_get_device(dep->slave, &adev);
2008                        if (!adev)
2009                                continue;
2010
2011                        adev->dep_unmet--;
2012                        if (!adev->dep_unmet)
2013                                acpi_bus_attach(adev);
2014                        list_del(&dep->node);
2015                        kfree(dep);
2016                }
2017        }
2018        mutex_unlock(&acpi_dep_list_lock);
2019}
2020EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
2021
2022/**
2023 * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2024 * @handle: Root of the namespace scope to scan.
2025 *
2026 * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2027 * found devices.
2028 *
2029 * If no devices were found, -ENODEV is returned, but it does not mean that
2030 * there has been a real error.  There just have been no suitable ACPI objects
2031 * in the table trunk from which the kernel could create a device and add an
2032 * appropriate driver.
2033 *
2034 * Must be called under acpi_scan_lock.
2035 */
2036int acpi_bus_scan(acpi_handle handle)
2037{
2038        void *device = NULL;
2039
2040        if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
2041                acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2042                                    acpi_bus_check_add, NULL, NULL, &device);
2043
2044        if (device) {
2045                acpi_bus_attach(device);
2046                return 0;
2047        }
2048        return -ENODEV;
2049}
2050EXPORT_SYMBOL(acpi_bus_scan);
2051
2052/**
2053 * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2054 * @adev: Root of the ACPI namespace scope to walk.
2055 *
2056 * Must be called under acpi_scan_lock.
2057 */
2058void acpi_bus_trim(struct acpi_device *adev)
2059{
2060        struct acpi_scan_handler *handler = adev->handler;
2061        struct acpi_device *child;
2062
2063        list_for_each_entry_reverse(child, &adev->children, node)
2064                acpi_bus_trim(child);
2065
2066        adev->flags.match_driver = false;
2067        if (handler) {
2068                if (handler->detach)
2069                        handler->detach(adev);
2070
2071                adev->handler = NULL;
2072        } else {
2073                device_release_driver(&adev->dev);
2074        }
2075        /*
2076         * Most likely, the device is going away, so put it into D3cold before
2077         * that.
2078         */
2079        acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2080        adev->flags.initialized = false;
2081        acpi_device_clear_enumerated(adev);
2082}
2083EXPORT_SYMBOL_GPL(acpi_bus_trim);
2084
2085int acpi_bus_register_early_device(int type)
2086{
2087        struct acpi_device *device = NULL;
2088        int result;
2089
2090        result = acpi_add_single_object(&device, NULL,
2091                                        type, ACPI_STA_DEFAULT);
2092        if (result)
2093                return result;
2094
2095        device->flags.match_driver = true;
2096        return device_attach(&device->dev);
2097}
2098EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
2099
2100static 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                device->flags.match_driver = true;
2117                result = device_attach(&device->dev);
2118                if (result < 0)
2119                        return result;
2120
2121                device_init_wakeup(&device->dev, true);
2122        }
2123
2124        if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2125                struct acpi_device *device = NULL;
2126
2127                result = acpi_add_single_object(&device, NULL,
2128                                                ACPI_BUS_TYPE_SLEEP_BUTTON,
2129                                                ACPI_STA_DEFAULT);
2130                if (result)
2131                        return result;
2132
2133                device->flags.match_driver = true;
2134                result = device_attach(&device->dev);
2135        }
2136
2137        return result < 0 ? result : 0;
2138}
2139
2140static void __init acpi_get_spcr_uart_addr(void)
2141{
2142        acpi_status status;
2143        struct acpi_table_spcr *spcr_ptr;
2144
2145        status = acpi_get_table(ACPI_SIG_SPCR, 0,
2146                                (struct acpi_table_header **)&spcr_ptr);
2147        if (ACPI_SUCCESS(status))
2148                spcr_uart_addr = spcr_ptr->serial_port.address;
2149        else
2150                printk(KERN_WARNING PREFIX "STAO table present, but SPCR is missing\n");
2151}
2152
2153static bool acpi_scan_initialized;
2154
2155int __init acpi_scan_init(void)
2156{
2157        int result;
2158        acpi_status status;
2159        struct acpi_table_stao *stao_ptr;
2160
2161        acpi_pci_root_init();
2162        acpi_pci_link_init();
2163        acpi_processor_init();
2164        acpi_lpss_init();
2165        acpi_apd_init();
2166        acpi_cmos_rtc_init();
2167        acpi_container_init();
2168        acpi_memory_hotplug_init();
2169        acpi_watchdog_init();
2170        acpi_pnp_init();
2171        acpi_int340x_thermal_init();
2172        acpi_amba_init();
2173        acpi_init_lpit();
2174
2175        acpi_scan_add_handler(&generic_device_handler);
2176
2177        /*
2178         * If there is STAO table, check whether it needs to ignore the UART
2179         * device in SPCR table.
2180         */
2181        status = acpi_get_table(ACPI_SIG_STAO, 0,
2182                                (struct acpi_table_header **)&stao_ptr);
2183        if (ACPI_SUCCESS(status)) {
2184                if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2185                        printk(KERN_INFO PREFIX "STAO Name List not yet supported.");
2186
2187                if (stao_ptr->ignore_uart)
2188                        acpi_get_spcr_uart_addr();
2189        }
2190
2191        acpi_gpe_apply_masked_gpes();
2192        acpi_update_all_gpes();
2193
2194        mutex_lock(&acpi_scan_lock);
2195        /*
2196         * Enumerate devices in the ACPI namespace.
2197         */
2198        result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2199        if (result)
2200                goto out;
2201
2202        result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2203        if (result)
2204                goto out;
2205
2206        /* Fixed feature devices do not exist on HW-reduced platform */
2207        if (!acpi_gbl_reduced_hardware) {
2208                result = acpi_bus_scan_fixed();
2209                if (result) {
2210                        acpi_detach_data(acpi_root->handle,
2211                                         acpi_scan_drop_device);
2212                        acpi_device_del(acpi_root);
2213                        put_device(&acpi_root->dev);
2214                        goto out;
2215                }
2216        }
2217
2218        acpi_scan_initialized = true;
2219
2220 out:
2221        mutex_unlock(&acpi_scan_lock);
2222        return result;
2223}
2224
2225static struct acpi_probe_entry *ape;
2226static int acpi_probe_count;
2227static DEFINE_MUTEX(acpi_probe_mutex);
2228
2229static int __init acpi_match_madt(struct acpi_subtable_header *header,
2230                                  const unsigned long end)
2231{
2232        if (!ape->subtable_valid || ape->subtable_valid(header, ape))
2233                if (!ape->probe_subtbl(header, end))
2234                        acpi_probe_count++;
2235
2236        return 0;
2237}
2238
2239int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2240{
2241        int count = 0;
2242
2243        if (acpi_disabled)
2244                return 0;
2245
2246        mutex_lock(&acpi_probe_mutex);
2247        for (ape = ap_head; nr; ape++, nr--) {
2248                if (ACPI_COMPARE_NAME(ACPI_SIG_MADT, ape->id)) {
2249                        acpi_probe_count = 0;
2250                        acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2251                        count += acpi_probe_count;
2252                } else {
2253                        int res;
2254                        res = acpi_table_parse(ape->id, ape->probe_table);
2255                        if (!res)
2256                                count++;
2257                }
2258        }
2259        mutex_unlock(&acpi_probe_mutex);
2260
2261        return count;
2262}
2263
2264struct acpi_table_events_work {
2265        struct work_struct work;
2266        void *table;
2267        u32 event;
2268};
2269
2270static void acpi_table_events_fn(struct work_struct *work)
2271{
2272        struct acpi_table_events_work *tew;
2273
2274        tew = container_of(work, struct acpi_table_events_work, work);
2275
2276        if (tew->event == ACPI_TABLE_EVENT_LOAD) {
2277                acpi_scan_lock_acquire();
2278                acpi_bus_scan(ACPI_ROOT_OBJECT);
2279                acpi_scan_lock_release();
2280        }
2281
2282        kfree(tew);
2283}
2284
2285void acpi_scan_table_handler(u32 event, void *table, void *context)
2286{
2287        struct acpi_table_events_work *tew;
2288
2289        if (!acpi_scan_initialized)
2290                return;
2291
2292        if (event != ACPI_TABLE_EVENT_LOAD)
2293                return;
2294
2295        tew = kmalloc(sizeof(*tew), GFP_KERNEL);
2296        if (!tew)
2297                return;
2298
2299        INIT_WORK(&tew->work, acpi_table_events_fn);
2300        tew->table = table;
2301        tew->event = event;
2302
2303        schedule_work(&tew->work);
2304}
2305
2306int acpi_reconfig_notifier_register(struct notifier_block *nb)
2307{
2308        return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2309}
2310EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2311
2312int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2313{
2314        return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2315}
2316EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);
2317