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/kernel.h>
   8 #include <linux/acpi.h>
   9 #include <linux/signal.h>
  10 #include <linux/kthread.h>
  11
  12 #include <acpi/acpi_drivers.h>
  13 #include <acpi/acinterp.h>      /* for acpi_ex_eisa_id_to_string() */
  14
  15 #define _COMPONENT              ACPI_BUS_COMPONENT
  16 ACPI_MODULE_NAME("scan");
  17 #define STRUCT_TO_INT(s)        (*((int*)&s))
  18 extern struct acpi_device *acpi_root;
  19
  20 #define ACPI_BUS_CLASS                  "system_bus"
  21 #define ACPI_BUS_HID                    "LNXSYBUS"
  22 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  23
  24 static LIST_HEAD(acpi_device_list);
  25 static LIST_HEAD(acpi_bus_id_list);
  26 DEFINE_SPINLOCK(acpi_device_lock);
  27 LIST_HEAD(acpi_wakeup_device_list);
  28
  29 struct acpi_device_bus_id{
  30         char bus_id[15];
  31         unsigned int instance_no;
  32         struct list_head node;
  33 };
  34
  35 /*
  36  * Creates hid/cid(s) string needed for modalias and uevent
  37  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
  38  * char *modalias: "acpi:IBM0001:ACPI0001"
  39 */
  40 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
  41                            int size)
  42 {
  43         int len;
  44         int count;
  45
  46         if (!acpi_dev->flags.hardware_id && !acpi_dev->flags.compatible_ids)
  47                 return -ENODEV;
  48
  49         len = snprintf(modalias, size, "acpi:");
  50         size -= len;
  51
  52         if (acpi_dev->flags.hardware_id) {
  53                 count = snprintf(&modalias[len], size, "%s:",
  54                                  acpi_dev->pnp.hardware_id);
  55                 if (count < 0 || count >= size)
  56                         return -EINVAL;
  57                 len += count;
  58                 size -= count;
  59         }
  60
  61         if (acpi_dev->flags.compatible_ids) {
  62                 struct acpi_compatible_id_list *cid_list;
  63                 int i;
  64
  65                 cid_list = acpi_dev->pnp.cid_list;
  66                 for (i = 0; i < cid_list->count; i++) {
  67                         count = snprintf(&modalias[len], size, "%s:",
  68                                          cid_list->id[i].value);
  69                         if (count < 0 || count >= size) {
  70                                 printk(KERN_ERR PREFIX "%s cid[%i] exceeds event buffer size",
  71                                        acpi_dev->pnp.device_name, i);
  72                                 break;
  73                         }
  74                         len += count;
  75                         size -= count;
  76                 }
  77         }
  78
  79         modalias[len] = '\0';
  80         return len;
  81 }
  82
  83 static ssize_t
  84 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
  85         struct acpi_device *acpi_dev = to_acpi_device(dev);
  86         int len;
  87
  88         /* Device has no HID and no CID or string is >1024 */
  89         len = create_modalias(acpi_dev, buf, 1024);
  90         if (len <= 0)
  91                 return 0;
  92         buf[len++] = '\n';
  93         return len;
  94 }
  95 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
  96
  97 static int acpi_bus_hot_remove_device(void *context)
  98 {
  99         struct acpi_device *device;
 100         acpi_handle handle = context;
 101         struct acpi_object_list arg_list;
 102         union acpi_object arg;
 103         acpi_status status = AE_OK;
 104
 105         if (acpi_bus_get_device(handle, &device))
 106                 return 0;
 107
 108         if (!device)
 109                 return 0;
 110
 111         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 112                 "Hot-removing device %s...\n", device->dev.bus_id));
 113
 114
 115         if (acpi_bus_trim(device, 1)) {
 116                 printk(KERN_ERR PREFIX
 117                                 "Removing device failed\n");
 118                 return -1;
 119         }
 120
 121         /* power off device */
 122         status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
 123         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
 124                 printk(KERN_WARNING PREFIX
 125                                 "Power-off device failed\n");
 126
 127         if (device->flags.lockable) {
 128                 arg_list.count = 1;
 129                 arg_list.pointer = &arg;
 130                 arg.type = ACPI_TYPE_INTEGER;
 131                 arg.integer.value = 0;
 132                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
 133         }
 134
 135         arg_list.count = 1;
 136         arg_list.pointer = &arg;
 137         arg.type = ACPI_TYPE_INTEGER;
 138         arg.integer.value = 1;
 139
 140         /*
 141          * TBD: _EJD support.
 142          */
 143         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
 144         if (ACPI_FAILURE(status))
 145                 return -ENODEV;
 146
 147         return 0;
 148 }
 149
 150 static ssize_t
 151 acpi_eject_store(struct device *d, struct device_attribute *attr,
 152                 const char *buf, size_t count)
 153 {
 154         int ret = count;
 155         acpi_status status;
 156         acpi_object_type type = 0;
 157         struct acpi_device *acpi_device = to_acpi_device(d);
 158         struct task_struct *task;
 159
 160         if ((!count) || (buf[0] != '1')) {
 161                 return -EINVAL;
 162         }
 163 #ifndef FORCE_EJECT
 164         if (acpi_device->driver == NULL) {
 165                 ret = -ENODEV;
 166                 goto err;
 167         }
 168 #endif
 169         status = acpi_get_type(acpi_device->handle, &type);
 170         if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
 171                 ret = -ENODEV;
 172                 goto err;
 173         }
 174
 175         /* remove the device in another thread to fix the deadlock issue */
 176         task = kthread_run(acpi_bus_hot_remove_device,
 177                                 acpi_device->handle, "acpi_hot_remove_device");
 178         if (IS_ERR(task))
 179                 ret = PTR_ERR(task);
 180 err:
 181         return ret;
 182 }
 183
 184 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 185
 186 static ssize_t
 187 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 188         struct acpi_device *acpi_dev = to_acpi_device(dev);
 189
 190         return sprintf(buf, "%s\n", acpi_dev->pnp.hardware_id);
 191 }
 192 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 193
 194 static ssize_t
 195 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 196         struct acpi_device *acpi_dev = to_acpi_device(dev);
 197         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 198         int result;
 199
 200         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 201         if(result)
 202                 goto end;
 203
 204         result = sprintf(buf, "%s\n", (char*)path.pointer);
 205         kfree(path.pointer);
 206   end:
 207         return result;
 208 }
 209 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 210
 211 static int acpi_device_setup_files(struct acpi_device *dev)
 212 {
 213         acpi_status status;
 214         acpi_handle temp;
 215         int result = 0;
 216
 217         /*
 218          * Devices gotten from FADT don't have a "path" attribute
 219          */
 220         if(dev->handle) {
 221                 result = device_create_file(&dev->dev, &dev_attr_path);
 222                 if(result)
 223                         goto end;
 224         }
 225
 226         if(dev->flags.hardware_id) {
 227                 result = device_create_file(&dev->dev, &dev_attr_hid);
 228                 if(result)
 229                         goto end;
 230         }
 231
 232         if (dev->flags.hardware_id || dev->flags.compatible_ids){
 233                 result = device_create_file(&dev->dev, &dev_attr_modalias);
 234                 if(result)
 235                         goto end;
 236         }
 237
 238         /*
 239          * If device has _EJ0, 'eject' file is created that is used to trigger
 240          * hot-removal function from userland.
 241          */
 242         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 243         if (ACPI_SUCCESS(status))
 244                 result = device_create_file(&dev->dev, &dev_attr_eject);
 245   end:
 246         return result;
 247 }
 248
 249 static void acpi_device_remove_files(struct acpi_device *dev)
 250 {
 251         acpi_status status;
 252         acpi_handle temp;
 253
 254         /*
 255          * If device has _EJ0, 'eject' file is created that is used to trigger
 256          * hot-removal function from userland.
 257          */
 258         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 259         if (ACPI_SUCCESS(status))
 260                 device_remove_file(&dev->dev, &dev_attr_eject);
 261
 262         if (dev->flags.hardware_id || dev->flags.compatible_ids)
 263                 device_remove_file(&dev->dev, &dev_attr_modalias);
 264
 265         if(dev->flags.hardware_id)
 266                 device_remove_file(&dev->dev, &dev_attr_hid);
 267         if(dev->handle)
 268                 device_remove_file(&dev->dev, &dev_attr_path);
 269 }
 270 /* --------------------------------------------------------------------------
 271                         ACPI Bus operations
 272    -------------------------------------------------------------------------- */
 273
 274 int acpi_match_device_ids(struct acpi_device *device,
 275                           const struct acpi_device_id *ids)
 276 {
 277         const struct acpi_device_id *id;
 278
 279         /*
 280          * If the device is not present, it is unnecessary to load device
 281          * driver for it.
 282          */
 283         if (!device->status.present)
 284                 return -ENODEV;
 285
 286         if (device->flags.hardware_id) {
 287                 for (id = ids; id->id[0]; id++) {
 288                         if (!strcmp((char*)id->id, device->pnp.hardware_id))
 289                                 return 0;
 290                 }
 291         }
 292
 293         if (device->flags.compatible_ids) {
 294                 struct acpi_compatible_id_list *cid_list = device->pnp.cid_list;
 295                 int i;
 296
 297                 for (id = ids; id->id[0]; id++) {
 298                         /* compare multiple _CID entries against driver ids */
 299                         for (i = 0; i < cid_list->count; i++) {
 300                                 if (!strcmp((char*)id->id,
 301                                             cid_list->id[i].value))
 302                                         return 0;
 303                         }
 304                 }
 305         }
 306
 307         return -ENOENT;
 308 }
 309 EXPORT_SYMBOL(acpi_match_device_ids);
 310
 311 static void acpi_device_release(struct device *dev)
 312 {
 313         struct acpi_device *acpi_dev = to_acpi_device(dev);
 314
 315         kfree(acpi_dev->pnp.cid_list);
 316         kfree(acpi_dev);
 317 }
 318
 319 static int acpi_device_suspend(struct device *dev, pm_message_t state)
 320 {
 321         struct acpi_device *acpi_dev = to_acpi_device(dev);
 322         struct acpi_driver *acpi_drv = acpi_dev->driver;
 323
 324         if (acpi_drv && acpi_drv->ops.suspend)
 325                 return acpi_drv->ops.suspend(acpi_dev, state);
 326         return 0;
 327 }
 328
 329 static int acpi_device_resume(struct device *dev)
 330 {
 331         struct acpi_device *acpi_dev = to_acpi_device(dev);
 332         struct acpi_driver *acpi_drv = acpi_dev->driver;
 333
 334         if (acpi_drv && acpi_drv->ops.resume)
 335                 return acpi_drv->ops.resume(acpi_dev);
 336         return 0;
 337 }
 338
 339 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 340 {
 341         struct acpi_device *acpi_dev = to_acpi_device(dev);
 342         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 343
 344         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 345 }
 346
 347 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 348 {
 349         struct acpi_device *acpi_dev = to_acpi_device(dev);
 350         int len;
 351
 352         if (add_uevent_var(env, "MODALIAS="))
 353                 return -ENOMEM;
 354         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 355                               sizeof(env->buf) - env->buflen);
 356         if (len >= (sizeof(env->buf) - env->buflen))
 357                 return -ENOMEM;
 358         env->buflen += len;
 359         return 0;
 360 }
 361
 362 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
 363 static int acpi_start_single_object(struct acpi_device *);
 364 static int acpi_device_probe(struct device * dev)
 365 {
 366         struct acpi_device *acpi_dev = to_acpi_device(dev);
 367         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 368         int ret;
 369
 370         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
 371         if (!ret) {
 372                 if (acpi_dev->bus_ops.acpi_op_start)
 373                         acpi_start_single_object(acpi_dev);
 374                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 375                         "Found driver [%s] for device [%s]\n",
 376                         acpi_drv->name, acpi_dev->pnp.bus_id));
 377                 get_device(dev);
 378         }
 379         return ret;
 380 }
 381
 382 static int acpi_device_remove(struct device * dev)
 383 {
 384         struct acpi_device *acpi_dev = to_acpi_device(dev);
 385         struct acpi_driver *acpi_drv = acpi_dev->driver;
 386
 387         if (acpi_drv) {
 388                 if (acpi_drv->ops.stop)
 389                         acpi_drv->ops.stop(acpi_dev, acpi_dev->removal_type);
 390                 if (acpi_drv->ops.remove)
 391                         acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
 392         }
 393         acpi_dev->driver = NULL;
 394         acpi_dev->driver_data = NULL;
 395
 396         put_device(dev);
 397         return 0;
 398 }
 399
 400 static void acpi_device_shutdown(struct device *dev)
 401 {
 402         struct acpi_device *acpi_dev = to_acpi_device(dev);
 403         struct acpi_driver *acpi_drv = acpi_dev->driver;
 404
 405         if (acpi_drv && acpi_drv->ops.shutdown)
 406                 acpi_drv->ops.shutdown(acpi_dev);
 407
 408         return ;
 409 }
 410
 411 struct bus_type acpi_bus_type = {
 412         .name           = "acpi",
 413         .suspend        = acpi_device_suspend,
 414         .resume         = acpi_device_resume,
 415         .shutdown       = acpi_device_shutdown,
 416         .match          = acpi_bus_match,
 417         .probe          = acpi_device_probe,
 418         .remove         = acpi_device_remove,
 419         .uevent         = acpi_device_uevent,
 420 };
 421
 422 static int acpi_device_register(struct acpi_device *device,
 423                                  struct acpi_device *parent)
 424 {
 425         int result;
 426         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 427         int found = 0;
 428         /*
 429          * Linkage
 430          * -------
 431          * Link this device to its parent and siblings.
 432          */
 433         INIT_LIST_HEAD(&device->children);
 434         INIT_LIST_HEAD(&device->node);
 435         INIT_LIST_HEAD(&device->g_list);
 436         INIT_LIST_HEAD(&device->wakeup_list);
 437
 438         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 439         if (!new_bus_id) {
 440                 printk(KERN_ERR PREFIX "Memory allocation error\n");
 441                 return -ENOMEM;
 442         }
 443
 444         spin_lock(&acpi_device_lock);
 445         /*
 446          * Find suitable bus_id and instance number in acpi_bus_id_list
 447          * If failed, create one and link it into acpi_bus_id_list
 448          */
 449         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 450                 if(!strcmp(acpi_device_bus_id->bus_id, device->flags.hardware_id? device->pnp.hardware_id : "device")) {
 451                         acpi_device_bus_id->instance_no ++;
 452                         found = 1;
 453                         kfree(new_bus_id);
 454                         break;
 455                 }
 456         }
 457         if(!found) {
 458                 acpi_device_bus_id = new_bus_id;
 459                 strcpy(acpi_device_bus_id->bus_id, device->flags.hardware_id ? device->pnp.hardware_id : "device");
 460                 acpi_device_bus_id->instance_no = 0;
 461                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 462         }
 463         sprintf(device->dev.bus_id, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 464
 465         if (device->parent) {
 466                 list_add_tail(&device->node, &device->parent->children);
 467                 list_add_tail(&device->g_list, &device->parent->g_list);
 468         } else
 469                 list_add_tail(&device->g_list, &acpi_device_list);
 470         if (device->wakeup.flags.valid)
 471                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 472         spin_unlock(&acpi_device_lock);
 473
 474         if (device->parent)
 475                 device->dev.parent = &parent->dev;
 476         device->dev.bus = &acpi_bus_type;
 477         device_initialize(&device->dev);
 478         device->dev.release = &acpi_device_release;
 479         result = device_add(&device->dev);
 480         if(result) {
 481                 dev_err(&device->dev, "Error adding device\n");
 482                 goto end;
 483         }
 484
 485         result = acpi_device_setup_files(device);
 486         if(result)
 487                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n", device->dev.bus_id);
 488
 489         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
 490         return 0;
 491   end:
 492         spin_lock(&acpi_device_lock);
 493         if (device->parent) {
 494                 list_del(&device->node);
 495                 list_del(&device->g_list);
 496         } else
 497                 list_del(&device->g_list);
 498         list_del(&device->wakeup_list);
 499         spin_unlock(&acpi_device_lock);
 500         return result;
 501 }
 502
 503 static void acpi_device_unregister(struct acpi_device *device, int type)
 504 {
 505         spin_lock(&acpi_device_lock);
 506         if (device->parent) {
 507                 list_del(&device->node);
 508                 list_del(&device->g_list);
 509         } else
 510                 list_del(&device->g_list);
 511
 512         list_del(&device->wakeup_list);
 513         spin_unlock(&acpi_device_lock);
 514
 515         acpi_detach_data(device->handle, acpi_bus_data_handler);
 516
 517         acpi_device_remove_files(device);
 518         device_unregister(&device->dev);
 519 }
 520
 521 /* --------------------------------------------------------------------------
 522                                  Driver Management
 523    -------------------------------------------------------------------------- */
 524 /**
 525  * acpi_bus_driver_init - add a device to a driver
 526  * @device: the device to add and initialize
 527  * @driver: driver for the device
 528  *
 529  * Used to initialize a device via its device driver.  Called whenever a
 530  * driver is bound to a device.  Invokes the driver's add() ops.
 531  */
 532 static int
 533 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
 534 {
 535         int result = 0;
 536
 537
 538         if (!device || !driver)
 539                 return -EINVAL;
 540
 541         if (!driver->ops.add)
 542                 return -ENOSYS;
 543
 544         result = driver->ops.add(device);
 545         if (result) {
 546                 device->driver = NULL;
 547                 device->driver_data = NULL;
 548                 return result;
 549         }
 550
 551         device->driver = driver;
 552
 553         /*
 554          * TBD - Configuration Management: Assign resources to device based
 555          * upon possible configuration and currently allocated resources.
 556          */
 557
 558         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 559                           "Driver successfully bound to device\n"));
 560         return 0;
 561 }
 562
 563 static int acpi_start_single_object(struct acpi_device *device)
 564 {
 565         int result = 0;
 566         struct acpi_driver *driver;
 567
 568
 569         if (!(driver = device->driver))
 570                 return 0;
 571
 572         if (driver->ops.start) {
 573                 result = driver->ops.start(device);
 574                 if (result && driver->ops.remove)
 575                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
 576         }
 577
 578         return result;
 579 }
 580
 581 /**
 582  * acpi_bus_register_driver - register a driver with the ACPI bus
 583  * @driver: driver being registered
 584  *
 585  * Registers a driver with the ACPI bus.  Searches the namespace for all
 586  * devices that match the driver's criteria and binds.  Returns zero for
 587  * success or a negative error status for failure.
 588  */
 589 int acpi_bus_register_driver(struct acpi_driver *driver)
 590 {
 591         int ret;
 592
 593         if (acpi_disabled)
 594                 return -ENODEV;
 595         driver->drv.name = driver->name;
 596         driver->drv.bus = &acpi_bus_type;
 597         driver->drv.owner = driver->owner;
 598
 599         ret = driver_register(&driver->drv);
 600         return ret;
 601 }
 602
 603 EXPORT_SYMBOL(acpi_bus_register_driver);
 604
 605 /**
 606  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
 607  * @driver: driver to unregister
 608  *
 609  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
 610  * devices that match the driver's criteria and unbinds.
 611  */
 612 void acpi_bus_unregister_driver(struct acpi_driver *driver)
 613 {
 614         driver_unregister(&driver->drv);
 615 }
 616
 617 EXPORT_SYMBOL(acpi_bus_unregister_driver);
 618
 619 /* --------------------------------------------------------------------------
 620                                  Device Enumeration
 621    -------------------------------------------------------------------------- */
 622 acpi_status
 623 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 624 {
 625         acpi_status status;
 626         acpi_handle tmp;
 627         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 628         union acpi_object *obj;
 629
 630         status = acpi_get_handle(handle, "_EJD", &tmp);
 631         if (ACPI_FAILURE(status))
 632                 return status;
 633
 634         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 635         if (ACPI_SUCCESS(status)) {
 636                 obj = buffer.pointer;
 637                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 638                                          ejd);
 639                 kfree(buffer.pointer);
 640         }
 641         return status;
 642 }
 643 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 644
 645 void acpi_bus_data_handler(acpi_handle handle, u32 function, void *context)
 646 {
 647
 648         /* TBD */
 649
 650         return;
 651 }
 652
 653 static int acpi_bus_get_perf_flags(struct acpi_device *device)
 654 {
 655         device->performance.state = ACPI_STATE_UNKNOWN;
 656         return 0;
 657 }
 658
 659 static acpi_status
 660 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
 661                                              union acpi_object *package)
 662 {
 663         int i = 0;
 664         union acpi_object *element = NULL;
 665
 666         if (!device || !package || (package->package.count < 2))
 667                 return AE_BAD_PARAMETER;
 668
 669         element = &(package->package.elements[0]);
 670         if (!element)
 671                 return AE_BAD_PARAMETER;
 672         if (element->type == ACPI_TYPE_PACKAGE) {
 673                 if ((element->package.count < 2) ||
 674                     (element->package.elements[0].type !=
 675                      ACPI_TYPE_LOCAL_REFERENCE)
 676                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 677                         return AE_BAD_DATA;
 678                 device->wakeup.gpe_device =
 679                     element->package.elements[0].reference.handle;
 680                 device->wakeup.gpe_number =
 681                     (u32) element->package.elements[1].integer.value;
 682         } else if (element->type == ACPI_TYPE_INTEGER) {
 683                 device->wakeup.gpe_number = element->integer.value;
 684         } else
 685                 return AE_BAD_DATA;
 686
 687         element = &(package->package.elements[1]);
 688         if (element->type != ACPI_TYPE_INTEGER) {
 689                 return AE_BAD_DATA;
 690         }
 691         device->wakeup.sleep_state = element->integer.value;
 692
 693         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
 694                 return AE_NO_MEMORY;
 695         }
 696         device->wakeup.resources.count = package->package.count - 2;
 697         for (i = 0; i < device->wakeup.resources.count; i++) {
 698                 element = &(package->package.elements[i + 2]);
 699                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
 700                         return AE_BAD_DATA;
 701
 702                 device->wakeup.resources.handles[i] = element->reference.handle;
 703         }
 704
 705         return AE_OK;
 706 }
 707
 708 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 709 {
 710         acpi_status status = 0;
 711         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 712         union acpi_object *package = NULL;
 713         int psw_error;
 714
 715         struct acpi_device_id button_device_ids[] = {
 716                 {"PNP0C0D", 0},
 717                 {"PNP0C0C", 0},
 718                 {"PNP0C0E", 0},
 719                 {"", 0},
 720         };
 721
 722         /* _PRW */
 723         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
 724         if (ACPI_FAILURE(status)) {
 725                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 726                 goto end;
 727         }
 728
 729         package = (union acpi_object *)buffer.pointer;
 730         status = acpi_bus_extract_wakeup_device_power_package(device, package);
 731         if (ACPI_FAILURE(status)) {
 732                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
 733                 goto end;
 734         }
 735
 736         kfree(buffer.pointer);
 737
 738         device->wakeup.flags.valid = 1;
 739         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
 740          * system for the ACPI device with the _PRW object.
 741          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 742          * So it is necessary to call _DSW object first. Only when it is not
 743          * present will the _PSW object used.
 744          */
 745         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
 746         if (psw_error)
 747                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 748                                 "error in _DSW or _PSW evaluation\n"));
 749
 750         /* Power button, Lid switch always enable wakeup */
 751         if (!acpi_match_device_ids(device, button_device_ids))
 752                 device->wakeup.flags.run_wake = 1;
 753
 754         /*
 755          * Don't set Power button GPE as run_wake
 756          * if Fixed Power button is used
 757          */
 758         if (!strcmp(device->pnp.hardware_id, "PNP0C0C") &&
 759                 !(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
 760                 device->wakeup.flags.run_wake = 0;
 761                 device->wakeup.flags.valid = 0;
 762         }
 763
 764       end:
 765         if (ACPI_FAILURE(status))
 766                 device->flags.wake_capable = 0;
 767         return 0;
 768 }
 769
 770 static int acpi_bus_get_power_flags(struct acpi_device *device)
 771 {
 772         acpi_status status = 0;
 773         acpi_handle handle = NULL;
 774         u32 i = 0;
 775
 776
 777         /*
 778          * Power Management Flags
 779          */
 780         status = acpi_get_handle(device->handle, "_PSC", &handle);
 781         if (ACPI_SUCCESS(status))
 782                 device->power.flags.explicit_get = 1;
 783         status = acpi_get_handle(device->handle, "_IRC", &handle);
 784         if (ACPI_SUCCESS(status))
 785                 device->power.flags.inrush_current = 1;
 786
 787         /*
 788          * Enumerate supported power management states
 789          */
 790         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
 791                 struct acpi_device_power_state *ps = &device->power.states[i];
 792                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
 793
 794                 /* Evaluate "_PRx" to se if power resources are referenced */
 795                 acpi_evaluate_reference(device->handle, object_name, NULL,
 796                                         &ps->resources);
 797                 if (ps->resources.count) {
 798                         device->power.flags.power_resources = 1;
 799                         ps->flags.valid = 1;
 800                 }
 801
 802                 /* Evaluate "_PSx" to see if we can do explicit sets */
 803                 object_name[2] = 'S';
 804                 status = acpi_get_handle(device->handle, object_name, &handle);
 805                 if (ACPI_SUCCESS(status)) {
 806                         ps->flags.explicit_set = 1;
 807                         ps->flags.valid = 1;
 808                 }
 809
 810                 /* State is valid if we have some power control */
 811                 if (ps->resources.count || ps->flags.explicit_set)
 812                         ps->flags.valid = 1;
 813
 814                 ps->power = -1; /* Unknown - driver assigned */
 815                 ps->latency = -1;       /* Unknown - driver assigned */
 816         }
 817
 818         /* Set defaults for D0 and D3 states (always valid) */
 819         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 820         device->power.states[ACPI_STATE_D0].power = 100;
 821         device->power.states[ACPI_STATE_D3].flags.valid = 1;
 822         device->power.states[ACPI_STATE_D3].power = 0;
 823
 824         /* TBD: System wake support and resource requirements. */
 825
 826         device->power.state = ACPI_STATE_UNKNOWN;
 827         acpi_bus_get_power(device->handle, &(device->power.state));
 828
 829         return 0;
 830 }
 831
 832 static int acpi_bus_get_flags(struct acpi_device *device)
 833 {
 834         acpi_status status = AE_OK;
 835         acpi_handle temp = NULL;
 836
 837
 838         /* Presence of _STA indicates 'dynamic_status' */
 839         status = acpi_get_handle(device->handle, "_STA", &temp);
 840         if (ACPI_SUCCESS(status))
 841                 device->flags.dynamic_status = 1;
 842
 843         /* Presence of _CID indicates 'compatible_ids' */
 844         status = acpi_get_handle(device->handle, "_CID", &temp);
 845         if (ACPI_SUCCESS(status))
 846                 device->flags.compatible_ids = 1;
 847
 848         /* Presence of _RMV indicates 'removable' */
 849         status = acpi_get_handle(device->handle, "_RMV", &temp);
 850         if (ACPI_SUCCESS(status))
 851                 device->flags.removable = 1;
 852
 853         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 854         status = acpi_get_handle(device->handle, "_EJD", &temp);
 855         if (ACPI_SUCCESS(status))
 856                 device->flags.ejectable = 1;
 857         else {
 858                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
 859                 if (ACPI_SUCCESS(status))
 860                         device->flags.ejectable = 1;
 861         }
 862
 863         /* Presence of _LCK indicates 'lockable' */
 864         status = acpi_get_handle(device->handle, "_LCK", &temp);
 865         if (ACPI_SUCCESS(status))
 866                 device->flags.lockable = 1;
 867
 868         /* Presence of _PS0|_PR0 indicates 'power manageable' */
 869         status = acpi_get_handle(device->handle, "_PS0", &temp);
 870         if (ACPI_FAILURE(status))
 871                 status = acpi_get_handle(device->handle, "_PR0", &temp);
 872         if (ACPI_SUCCESS(status))
 873                 device->flags.power_manageable = 1;
 874
 875         /* Presence of _PRW indicates wake capable */
 876         status = acpi_get_handle(device->handle, "_PRW", &temp);
 877         if (ACPI_SUCCESS(status))
 878                 device->flags.wake_capable = 1;
 879
 880         /* TBD: Performance management */
 881
 882         return 0;
 883 }
 884
 885 static void acpi_device_get_busid(struct acpi_device *device,
 886                                   acpi_handle handle, int type)
 887 {
 888         char bus_id[5] = { '?', 0 };
 889         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
 890         int i = 0;
 891
 892         /*
 893          * Bus ID
 894          * ------
 895          * The device's Bus ID is simply the object name.
 896          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
 897          */
 898         switch (type) {
 899         case ACPI_BUS_TYPE_SYSTEM:
 900                 strcpy(device->pnp.bus_id, "ACPI");
 901                 break;
 902         case ACPI_BUS_TYPE_POWER_BUTTON:
 903                 strcpy(device->pnp.bus_id, "PWRF");
 904                 break;
 905         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 906                 strcpy(device->pnp.bus_id, "SLPF");
 907                 break;
 908         default:
 909                 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 910                 /* Clean up trailing underscores (if any) */
 911                 for (i = 3; i > 1; i--) {
 912                         if (bus_id[i] == '_')
 913                                 bus_id[i] = '\0';
 914                         else
 915                                 break;
 916                 }
 917                 strcpy(device->pnp.bus_id, bus_id);
 918                 break;
 919         }
 920 }
 921
 922 /*
 923  * acpi_bay_match - see if a device is an ejectable driver bay
 924  *
 925  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
 926  * then we can safely call it an ejectable drive bay
 927  */
 928 static int acpi_bay_match(struct acpi_device *device){
 929         acpi_status status;
 930         acpi_handle handle;
 931         acpi_handle tmp;
 932         acpi_handle phandle;
 933
 934         handle = device->handle;
 935
 936         status = acpi_get_handle(handle, "_EJ0", &tmp);
 937         if (ACPI_FAILURE(status))
 938                 return -ENODEV;
 939
 940         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
 941                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
 942                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
 943                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
 944                 return 0;
 945
 946         if (acpi_get_parent(handle, &phandle))
 947                 return -ENODEV;
 948
 949         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
 950                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
 951                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
 952                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
 953                 return 0;
 954
 955         return -ENODEV;
 956 }
 957
 958 /*
 959  * acpi_dock_match - see if a device has a _DCK method
 960  */
 961 static int acpi_dock_match(struct acpi_device *device)
 962 {
 963         acpi_handle tmp;
 964         return acpi_get_handle(device->handle, "_DCK", &tmp);
 965 }
 966
 967 static void acpi_device_set_id(struct acpi_device *device,
 968                                struct acpi_device *parent, acpi_handle handle,
 969                                int type)
 970 {
 971         struct acpi_device_info *info;
 972         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 973         char *hid = NULL;
 974         char *uid = NULL;
 975         struct acpi_compatible_id_list *cid_list = NULL;
 976         const char *cid_add = NULL;
 977         acpi_status status;
 978
 979         switch (type) {
 980         case ACPI_BUS_TYPE_DEVICE:
 981                 status = acpi_get_object_info(handle, &buffer);
 982                 if (ACPI_FAILURE(status)) {
 983                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
 984                         return;
 985                 }
 986
 987                 info = buffer.pointer;
 988                 if (info->valid & ACPI_VALID_HID)
 989                         hid = info->hardware_id.value;
 990                 if (info->valid & ACPI_VALID_UID)
 991                         uid = info->unique_id.value;
 992                 if (info->valid & ACPI_VALID_CID)
 993                         cid_list = &info->compatibility_id;
 994                 if (info->valid & ACPI_VALID_ADR) {
 995                         device->pnp.bus_address = info->address;
 996                         device->flags.bus_address = 1;
 997                 }
 998
 999                 /* If we have a video/bay/dock device, add our selfdefined
1000                    HID to the CID list. Like that the video/bay/dock drivers
1001                    will get autoloaded and the device might still match
1002                    against another driver.
1003                 */
1004                 if (acpi_is_video_device(device))
1005                         cid_add = ACPI_VIDEO_HID;
1006                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1007                         cid_add = ACPI_BAY_HID;
1008                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1009                         cid_add = ACPI_DOCK_HID;
1010
1011                 break;
1012         case ACPI_BUS_TYPE_POWER:
1013                 hid = ACPI_POWER_HID;
1014                 break;
1015         case ACPI_BUS_TYPE_PROCESSOR:
1016                 hid = ACPI_PROCESSOR_HID;
1017                 break;
1018         case ACPI_BUS_TYPE_SYSTEM:
1019                 hid = ACPI_SYSTEM_HID;
1020                 break;
1021         case ACPI_BUS_TYPE_THERMAL:
1022                 hid = ACPI_THERMAL_HID;
1023                 break;
1024         case ACPI_BUS_TYPE_POWER_BUTTON:
1025                 hid = ACPI_BUTTON_HID_POWERF;
1026                 break;
1027         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1028                 hid = ACPI_BUTTON_HID_SLEEPF;
1029                 break;
1030         }
1031
1032         /*
1033          * \_SB
1034          * ----
1035          * Fix for the system root bus device -- the only root-level device.
1036          */
1037         if (((acpi_handle)parent == ACPI_ROOT_OBJECT) && (type == ACPI_BUS_TYPE_DEVICE)) {
1038                 hid = ACPI_BUS_HID;
1039                 strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1040                 strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1041         }
1042
1043         if (hid) {
1044                 strcpy(device->pnp.hardware_id, hid);
1045                 device->flags.hardware_id = 1;
1046         }
1047         if (uid) {
1048                 strcpy(device->pnp.unique_id, uid);
1049                 device->flags.unique_id = 1;
1050         }
1051         if (cid_list || cid_add) {
1052                 struct  acpi_compatible_id_list *list;
1053                 int size = 0;
1054                 int count = 0;
1055
1056                 if (cid_list) {
1057                         size = cid_list->size;
1058                 } else if (cid_add) {
1059                         size = sizeof(struct acpi_compatible_id_list);
1060                         cid_list = ACPI_ALLOCATE_ZEROED((acpi_size) size);
1061                         if (!cid_list) {
1062                                 printk(KERN_ERR "Memory allocation error\n");
1063                                 kfree(buffer.pointer);
1064                                 return;
1065                         } else {
1066                                 cid_list->count = 0;
1067                                 cid_list->size = size;
1068                         }
1069                 }
1070                 if (cid_add)
1071                         size += sizeof(struct acpi_compatible_id);
1072                 list = kmalloc(size, GFP_KERNEL);
1073
1074                 if (list) {
1075                         if (cid_list) {
1076                                 memcpy(list, cid_list, cid_list->size);
1077                                 count = cid_list->count;
1078                         }
1079                         if (cid_add) {
1080                                 strncpy(list->id[count].value, cid_add,
1081                                         ACPI_MAX_CID_LENGTH);
1082                                 count++;
1083                                 device->flags.compatible_ids = 1;
1084                         }
1085                         list->size = size;
1086                         list->count = count;
1087                         device->pnp.cid_list = list;
1088                 } else
1089                         printk(KERN_ERR PREFIX "Memory allocation error\n");
1090         }
1091
1092         kfree(buffer.pointer);
1093 }
1094
1095 static int acpi_device_set_context(struct acpi_device *device, int type)
1096 {
1097         acpi_status status = AE_OK;
1098         int result = 0;
1099         /*
1100          * Context
1101          * -------
1102          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1103          * resolutions from handle->device very efficient.  Note that we need
1104          * to be careful with fixed-feature devices as they all attach to the
1105          * root object.
1106          */
1107         if (type != ACPI_BUS_TYPE_POWER_BUTTON &&
1108             type != ACPI_BUS_TYPE_SLEEP_BUTTON) {
1109                 status = acpi_attach_data(device->handle,
1110                                           acpi_bus_data_handler, device);
1111
1112                 if (ACPI_FAILURE(status)) {
1113                         printk(KERN_ERR PREFIX "Error attaching device data\n");
1114                         result = -ENODEV;
1115                 }
1116         }
1117         return result;
1118 }
1119
1120 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1121 {
1122         if (!dev)
1123                 return -EINVAL;
1124
1125         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1126         device_release_driver(&dev->dev);
1127
1128         if (!rmdevice)
1129                 return 0;
1130
1131         /*
1132          * unbind _ADR-Based Devices when hot removal
1133          */
1134         if (dev->flags.bus_address) {
1135                 if ((dev->parent) && (dev->parent->ops.unbind))
1136                         dev->parent->ops.unbind(dev);
1137         }
1138         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1139
1140         return 0;
1141 }
1142
1143 static int
1144 acpi_add_single_object(struct acpi_device **child,
1145                        struct acpi_device *parent, acpi_handle handle, int type,
1146                         struct acpi_bus_ops *ops)
1147 {
1148         int result = 0;
1149         struct acpi_device *device = NULL;
1150
1151
1152         if (!child)
1153                 return -EINVAL;
1154
1155         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1156         if (!device) {
1157                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1158                 return -ENOMEM;
1159         }
1160
1161         device->handle = handle;
1162         device->parent = parent;
1163         device->bus_ops = *ops; /* workround for not call .start */
1164
1165
1166         acpi_device_get_busid(device, handle, type);
1167
1168         /*
1169          * Flags
1170          * -----
1171          * Get prior to calling acpi_bus_get_status() so we know whether
1172          * or not _STA is present.  Note that we only look for object
1173          * handles -- cannot evaluate objects until we know the device is
1174          * present and properly initialized.
1175          */
1176         result = acpi_bus_get_flags(device);
1177         if (result)
1178                 goto end;
1179
1180         /*
1181          * Status
1182          * ------
1183          * See if the device is present.  We always assume that non-Device
1184          * and non-Processor objects (e.g. thermal zones, power resources,
1185          * etc.) are present, functioning, etc. (at least when parent object
1186          * is present).  Note that _STA has a different meaning for some
1187          * objects (e.g. power resources) so we need to be careful how we use
1188          * it.
1189          */
1190         switch (type) {
1191         case ACPI_BUS_TYPE_PROCESSOR:
1192         case ACPI_BUS_TYPE_DEVICE:
1193                 result = acpi_bus_get_status(device);
1194                 if (ACPI_FAILURE(result)) {
1195                         result = -ENODEV;
1196                         goto end;
1197                 }
1198                 /*
1199                  * When the device is neither present nor functional, the
1200                  * device should not be added to Linux ACPI device tree.
1201                  * When the status of the device is not present but functinal,
1202                  * it should be added to Linux ACPI tree. For example : bay
1203                  * device , dock device.
1204                  * In such conditions it is unncessary to check whether it is
1205                  * bay device or dock device.
1206                  */
1207                 if (!device->status.present && !device->status.functional) {
1208                         result = -ENODEV;
1209                         goto end;
1210                 }
1211                 break;
1212         default:
1213                 STRUCT_TO_INT(device->status) =
1214                     ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
1215                     ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
1216                 break;
1217         }
1218
1219         /*
1220          * Initialize Device
1221          * -----------------
1222          * TBD: Synch with Core's enumeration/initialization process.
1223          */
1224
1225         /*
1226          * Hardware ID, Unique ID, & Bus Address
1227          * -------------------------------------
1228          */
1229         acpi_device_set_id(device, parent, handle, type);
1230
1231         /*
1232          * The ACPI device is attached to acpi handle before getting
1233          * the power/wakeup/peformance flags. Otherwise OS can't get
1234          * the corresponding ACPI device by the acpi handle in the course
1235          * of getting the power/wakeup/performance flags.
1236          */
1237         result = acpi_device_set_context(device, type);
1238         if (result)
1239                 goto end;
1240
1241         /*
1242          * Power Management
1243          * ----------------
1244          */
1245         if (device->flags.power_manageable) {
1246                 result = acpi_bus_get_power_flags(device);
1247                 if (result)
1248                         goto end;
1249         }
1250
1251         /*
1252          * Wakeup device management
1253          *-----------------------
1254          */
1255         if (device->flags.wake_capable) {
1256                 result = acpi_bus_get_wakeup_device_flags(device);
1257                 if (result)
1258                         goto end;
1259         }
1260
1261         /*
1262          * Performance Management
1263          * ----------------------
1264          */
1265         if (device->flags.performance_manageable) {
1266                 result = acpi_bus_get_perf_flags(device);
1267                 if (result)
1268                         goto end;
1269         }
1270
1271
1272         result = acpi_device_register(device, parent);
1273
1274         /*
1275          * Bind _ADR-Based Devices when hot add
1276          */
1277         if (device->flags.bus_address) {
1278                 if (device->parent && device->parent->ops.bind)
1279                         device->parent->ops.bind(device);
1280         }
1281
1282       end:
1283         if (!result)
1284                 *child = device;
1285         else {
1286                 kfree(device->pnp.cid_list);
1287                 kfree(device);
1288         }
1289
1290         return result;
1291 }
1292
1293 static int acpi_bus_scan(struct acpi_device *start, struct acpi_bus_ops *ops)
1294 {
1295         acpi_status status = AE_OK;
1296         struct acpi_device *parent = NULL;
1297         struct acpi_device *child = NULL;
1298         acpi_handle phandle = NULL;
1299         acpi_handle chandle = NULL;
1300         acpi_object_type type = 0;
1301         u32 level = 1;
1302
1303
1304         if (!start)
1305                 return -EINVAL;
1306
1307         parent = start;
1308         phandle = start->handle;
1309
1310         /*
1311          * Parse through the ACPI namespace, identify all 'devices', and
1312          * create a new 'struct acpi_device' for each.
1313          */
1314         while ((level > 0) && parent) {
1315
1316                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1317                                               chandle, &chandle);
1318
1319                 /*
1320                  * If this scope is exhausted then move our way back up.
1321                  */
1322                 if (ACPI_FAILURE(status)) {
1323                         level--;
1324                         chandle = phandle;
1325                         acpi_get_parent(phandle, &phandle);
1326                         if (parent->parent)
1327                                 parent = parent->parent;
1328                         continue;
1329                 }
1330
1331                 status = acpi_get_type(chandle, &type);
1332                 if (ACPI_FAILURE(status))
1333                         continue;
1334
1335                 /*
1336                  * If this is a scope object then parse it (depth-first).
1337                  */
1338                 if (type == ACPI_TYPE_LOCAL_SCOPE) {
1339                         level++;
1340                         phandle = chandle;
1341                         chandle = NULL;
1342                         continue;
1343                 }
1344
1345                 /*
1346                  * We're only interested in objects that we consider 'devices'.
1347                  */
1348                 switch (type) {
1349                 case ACPI_TYPE_DEVICE:
1350                         type = ACPI_BUS_TYPE_DEVICE;
1351                         break;
1352                 case ACPI_TYPE_PROCESSOR:
1353                         type = ACPI_BUS_TYPE_PROCESSOR;
1354                         break;
1355                 case ACPI_TYPE_THERMAL:
1356                         type = ACPI_BUS_TYPE_THERMAL;
1357                         break;
1358                 case ACPI_TYPE_POWER:
1359                         type = ACPI_BUS_TYPE_POWER;
1360                         break;
1361                 default:
1362                         continue;
1363                 }
1364
1365                 if (ops->acpi_op_add)
1366                         status = acpi_add_single_object(&child, parent,
1367                                 chandle, type, ops);
1368                 else
1369                         status = acpi_bus_get_device(chandle, &child);
1370
1371                 if (ACPI_FAILURE(status))
1372                         continue;
1373
1374                 if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1375                         status = acpi_start_single_object(child);
1376                         if (ACPI_FAILURE(status))
1377                                 continue;
1378                 }
1379
1380                 /*
1381                  * If the device is present, enabled, and functioning then
1382                  * parse its scope (depth-first).  Note that we need to
1383                  * represent absent devices to facilitate PnP notifications
1384                  * -- but only the subtree head (not all of its children,
1385                  * which will be enumerated when the parent is inserted).
1386                  *
1387                  * TBD: Need notifications and other detection mechanisms
1388                  *      in place before we can fully implement this.
1389                  */
1390                  /*
1391                  * When the device is not present but functional, it is also
1392                  * necessary to scan the children of this device.
1393                  */
1394                 if (child->status.present || (!child->status.present &&
1395                                         child->status.functional)) {
1396                         status = acpi_get_next_object(ACPI_TYPE_ANY, chandle,
1397                                                       NULL, NULL);
1398                         if (ACPI_SUCCESS(status)) {
1399                                 level++;
1400                                 phandle = chandle;
1401                                 chandle = NULL;
1402                                 parent = child;
1403                         }
1404                 }
1405         }
1406
1407         return 0;
1408 }
1409
1410 int
1411 acpi_bus_add(struct acpi_device **child,
1412              struct acpi_device *parent, acpi_handle handle, int type)
1413 {
1414         int result;
1415         struct acpi_bus_ops ops;
1416
1417         memset(&ops, 0, sizeof(ops));
1418         ops.acpi_op_add = 1;
1419
1420         result = acpi_add_single_object(child, parent, handle, type, &ops);
1421         if (!result)
1422                 result = acpi_bus_scan(*child, &ops);
1423
1424         return result;
1425 }
1426
1427 EXPORT_SYMBOL(acpi_bus_add);
1428
1429 int acpi_bus_start(struct acpi_device *device)
1430 {
1431         int result;
1432         struct acpi_bus_ops ops;
1433
1434
1435         if (!device)
1436                 return -EINVAL;
1437
1438         result = acpi_start_single_object(device);
1439         if (!result) {
1440                 memset(&ops, 0, sizeof(ops));
1441                 ops.acpi_op_start = 1;
1442                 result = acpi_bus_scan(device, &ops);
1443         }
1444         return result;
1445 }
1446
1447 EXPORT_SYMBOL(acpi_bus_start);
1448
1449 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1450 {
1451         acpi_status status;
1452         struct acpi_device *parent, *child;
1453         acpi_handle phandle, chandle;
1454         acpi_object_type type;
1455         u32 level = 1;
1456         int err = 0;
1457
1458         parent = start;
1459         phandle = start->handle;
1460         child = chandle = NULL;
1461
1462         while ((level > 0) && parent && (!err)) {
1463                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1464                                               chandle, &chandle);
1465
1466                 /*
1467                  * If this scope is exhausted then move our way back up.
1468                  */
1469                 if (ACPI_FAILURE(status)) {
1470                         level--;
1471                         chandle = phandle;
1472                         acpi_get_parent(phandle, &phandle);
1473                         child = parent;
1474                         parent = parent->parent;
1475
1476                         if (level == 0)
1477                                 err = acpi_bus_remove(child, rmdevice);
1478                         else
1479                                 err = acpi_bus_remove(child, 1);
1480
1481                         continue;
1482                 }
1483
1484                 status = acpi_get_type(chandle, &type);
1485                 if (ACPI_FAILURE(status)) {
1486                         continue;
1487                 }
1488                 /*
1489                  * If there is a device corresponding to chandle then
1490                  * parse it (depth-first).
1491                  */
1492                 if (acpi_bus_get_device(chandle, &child) == 0) {
1493                         level++;
1494                         phandle = chandle;
1495                         chandle = NULL;
1496                         parent = child;
1497                 }
1498                 continue;
1499         }
1500         return err;
1501 }
1502 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1503
1504
1505 static int acpi_bus_scan_fixed(struct acpi_device *root)
1506 {
1507         int result = 0;
1508         struct acpi_device *device = NULL;
1509         struct acpi_bus_ops ops;
1510
1511         if (!root)
1512                 return -ENODEV;
1513
1514         memset(&ops, 0, sizeof(ops));
1515         ops.acpi_op_add = 1;
1516         ops.acpi_op_start = 1;
1517
1518         /*
1519          * Enumerate all fixed-feature devices.
1520          */
1521         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1522                 result = acpi_add_single_object(&device, acpi_root,
1523                                                 NULL,
1524                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1525                                                 &ops);
1526         }
1527
1528         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1529                 result = acpi_add_single_object(&device, acpi_root,
1530                                                 NULL,
1531                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1532                                                 &ops);
1533         }
1534
1535         return result;
1536 }
1537
1538
1539 static int __init acpi_scan_init(void)
1540 {
1541         int result;
1542         struct acpi_bus_ops ops;
1543
1544
1545         if (acpi_disabled)
1546                 return 0;
1547
1548         memset(&ops, 0, sizeof(ops));
1549         ops.acpi_op_add = 1;
1550         ops.acpi_op_start = 1;
1551
1552         result = bus_register(&acpi_bus_type);
1553         if (result) {
1554                 /* We don't want to quit even if we failed to add suspend/resume */
1555                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1556         }
1557
1558         /*
1559          * Create the root device in the bus's device tree
1560          */
1561         result = acpi_add_single_object(&acpi_root, NULL, ACPI_ROOT_OBJECT,
1562                                         ACPI_BUS_TYPE_SYSTEM, &ops);
1563         if (result)
1564                 goto Done;
1565
1566         /*
1567          * Enumerate devices in the ACPI namespace.
1568          */
1569         result = acpi_bus_scan_fixed(acpi_root);
1570
1571         if (!result)
1572                 result = acpi_bus_scan(acpi_root, &ops);
1573
1574         if (result)
1575                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1576
1577       Done:
1578         return result;
1579 }
1580
1581 subsys_initcall(acpi_scan_init);