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
  14 #include "internal.h"
  15
  16 #define _COMPONENT              ACPI_BUS_COMPONENT
  17 ACPI_MODULE_NAME("scan");
  18 #define STRUCT_TO_INT(s)        (*((int*)&s))
  19 extern struct acpi_device *acpi_root;
  20
  21 #define ACPI_BUS_CLASS                  "system_bus"
  22 #define ACPI_BUS_HID                    "LNXSYBUS"
  23 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  24
  25 static LIST_HEAD(acpi_device_list);
  26 static LIST_HEAD(acpi_bus_id_list);
  27 DEFINE_MUTEX(acpi_device_lock);
  28 LIST_HEAD(acpi_wakeup_device_list);
  29
  30 struct acpi_device_bus_id{
  31         char bus_id[15];
  32         unsigned int instance_no;
  33         struct list_head node;
  34 };
  35
  36 /*
  37  * Creates hid/cid(s) string needed for modalias and uevent
  38  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
  39  * char *modalias: "acpi:IBM0001:ACPI0001"
  40 */
  41 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
  42                            int size)
  43 {
  44         int len;
  45         int count;
  46
  47         if (!acpi_dev->flags.hardware_id && !acpi_dev->flags.compatible_ids)
  48                 return -ENODEV;
  49
  50         len = snprintf(modalias, size, "acpi:");
  51         size -= len;
  52
  53         if (acpi_dev->flags.hardware_id) {
  54                 count = snprintf(&modalias[len], size, "%s:",
  55                                  acpi_dev->pnp.hardware_id);
  56                 if (count < 0 || count >= size)
  57                         return -EINVAL;
  58                 len += count;
  59                 size -= count;
  60         }
  61
  62         if (acpi_dev->flags.compatible_ids) {
  63                 struct acpi_compatible_id_list *cid_list;
  64                 int i;
  65
  66                 cid_list = acpi_dev->pnp.cid_list;
  67                 for (i = 0; i < cid_list->count; i++) {
  68                         count = snprintf(&modalias[len], size, "%s:",
  69                                          cid_list->id[i].value);
  70                         if (count < 0 || count >= size) {
  71                                 printk(KERN_ERR PREFIX "%s cid[%i] exceeds event buffer size",
  72                                        acpi_dev->pnp.device_name, i);
  73                                 break;
  74                         }
  75                         len += count;
  76                         size -= count;
  77                 }
  78         }
  79
  80         modalias[len] = '\0';
  81         return len;
  82 }
  83
  84 static ssize_t
  85 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
  86         struct acpi_device *acpi_dev = to_acpi_device(dev);
  87         int len;
  88
  89         /* Device has no HID and no CID or string is >1024 */
  90         len = create_modalias(acpi_dev, buf, 1024);
  91         if (len <= 0)
  92                 return 0;
  93         buf[len++] = '\n';
  94         return len;
  95 }
  96 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
  97
  98 static void acpi_bus_hot_remove_device(void *context)
  99 {
 100         struct acpi_device *device;
 101         acpi_handle handle = context;
 102         struct acpi_object_list arg_list;
 103         union acpi_object arg;
 104         acpi_status status = AE_OK;
 105
 106         if (acpi_bus_get_device(handle, &device))
 107                 return;
 108
 109         if (!device)
 110                 return;
 111
 112         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 113                 "Hot-removing device %s...\n", dev_name(&device->dev)));
 114
 115         if (acpi_bus_trim(device, 1)) {
 116                 printk(KERN_ERR PREFIX
 117                                 "Removing device failed\n");
 118                 return;
 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                 printk(KERN_WARNING PREFIX
 146                                 "Eject device failed\n");
 147
 148         return;
 149 }
 150
 151 static ssize_t
 152 acpi_eject_store(struct device *d, struct device_attribute *attr,
 153                 const char *buf, size_t count)
 154 {
 155         int ret = count;
 156         acpi_status status;
 157         acpi_object_type type = 0;
 158         struct acpi_device *acpi_device = to_acpi_device(d);
 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         acpi_os_hotplug_execute(acpi_bus_hot_remove_device, acpi_device->handle);
 176 err:
 177         return ret;
 178 }
 179
 180 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 181
 182 static ssize_t
 183 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 184         struct acpi_device *acpi_dev = to_acpi_device(dev);
 185
 186         return sprintf(buf, "%s\n", acpi_dev->pnp.hardware_id);
 187 }
 188 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 189
 190 static ssize_t
 191 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 192         struct acpi_device *acpi_dev = to_acpi_device(dev);
 193         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 194         int result;
 195
 196         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 197         if (result)
 198                 goto end;
 199
 200         result = sprintf(buf, "%s\n", (char*)path.pointer);
 201         kfree(path.pointer);
 202 end:
 203         return result;
 204 }
 205 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 206
 207 static int acpi_device_setup_files(struct acpi_device *dev)
 208 {
 209         acpi_status status;
 210         acpi_handle temp;
 211         int result = 0;
 212
 213         /*
 214          * Devices gotten from FADT don't have a "path" attribute
 215          */
 216         if (dev->handle) {
 217                 result = device_create_file(&dev->dev, &dev_attr_path);
 218                 if (result)
 219                         goto end;
 220         }
 221
 222         if (dev->flags.hardware_id) {
 223                 result = device_create_file(&dev->dev, &dev_attr_hid);
 224                 if (result)
 225                         goto end;
 226         }
 227
 228         if (dev->flags.hardware_id || dev->flags.compatible_ids) {
 229                 result = device_create_file(&dev->dev, &dev_attr_modalias);
 230                 if (result)
 231                         goto end;
 232         }
 233
 234         /*
 235          * If device has _EJ0, 'eject' file is created that is used to trigger
 236          * hot-removal function from userland.
 237          */
 238         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 239         if (ACPI_SUCCESS(status))
 240                 result = device_create_file(&dev->dev, &dev_attr_eject);
 241 end:
 242         return result;
 243 }
 244
 245 static void acpi_device_remove_files(struct acpi_device *dev)
 246 {
 247         acpi_status status;
 248         acpi_handle temp;
 249
 250         /*
 251          * If device has _EJ0, 'eject' file is created that is used to trigger
 252          * hot-removal function from userland.
 253          */
 254         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 255         if (ACPI_SUCCESS(status))
 256                 device_remove_file(&dev->dev, &dev_attr_eject);
 257
 258         if (dev->flags.hardware_id || dev->flags.compatible_ids)
 259                 device_remove_file(&dev->dev, &dev_attr_modalias);
 260
 261         if (dev->flags.hardware_id)
 262                 device_remove_file(&dev->dev, &dev_attr_hid);
 263         if (dev->handle)
 264                 device_remove_file(&dev->dev, &dev_attr_path);
 265 }
 266 /* --------------------------------------------------------------------------
 267                         ACPI Bus operations
 268    -------------------------------------------------------------------------- */
 269
 270 int acpi_match_device_ids(struct acpi_device *device,
 271                           const struct acpi_device_id *ids)
 272 {
 273         const struct acpi_device_id *id;
 274
 275         /*
 276          * If the device is not present, it is unnecessary to load device
 277          * driver for it.
 278          */
 279         if (!device->status.present)
 280                 return -ENODEV;
 281
 282         if (device->flags.hardware_id) {
 283                 for (id = ids; id->id[0]; id++) {
 284                         if (!strcmp((char*)id->id, device->pnp.hardware_id))
 285                                 return 0;
 286                 }
 287         }
 288
 289         if (device->flags.compatible_ids) {
 290                 struct acpi_compatible_id_list *cid_list = device->pnp.cid_list;
 291                 int i;
 292
 293                 for (id = ids; id->id[0]; id++) {
 294                         /* compare multiple _CID entries against driver ids */
 295                         for (i = 0; i < cid_list->count; i++) {
 296                                 if (!strcmp((char*)id->id,
 297                                             cid_list->id[i].value))
 298                                         return 0;
 299                         }
 300                 }
 301         }
 302
 303         return -ENOENT;
 304 }
 305 EXPORT_SYMBOL(acpi_match_device_ids);
 306
 307 static void acpi_device_release(struct device *dev)
 308 {
 309         struct acpi_device *acpi_dev = to_acpi_device(dev);
 310
 311         kfree(acpi_dev->pnp.cid_list);
 312         kfree(acpi_dev);
 313 }
 314
 315 static int acpi_device_suspend(struct device *dev, pm_message_t state)
 316 {
 317         struct acpi_device *acpi_dev = to_acpi_device(dev);
 318         struct acpi_driver *acpi_drv = acpi_dev->driver;
 319
 320         if (acpi_drv && acpi_drv->ops.suspend)
 321                 return acpi_drv->ops.suspend(acpi_dev, state);
 322         return 0;
 323 }
 324
 325 static int acpi_device_resume(struct device *dev)
 326 {
 327         struct acpi_device *acpi_dev = to_acpi_device(dev);
 328         struct acpi_driver *acpi_drv = acpi_dev->driver;
 329
 330         if (acpi_drv && acpi_drv->ops.resume)
 331                 return acpi_drv->ops.resume(acpi_dev);
 332         return 0;
 333 }
 334
 335 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 336 {
 337         struct acpi_device *acpi_dev = to_acpi_device(dev);
 338         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 339
 340         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 341 }
 342
 343 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 344 {
 345         struct acpi_device *acpi_dev = to_acpi_device(dev);
 346         int len;
 347
 348         if (add_uevent_var(env, "MODALIAS="))
 349                 return -ENOMEM;
 350         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 351                               sizeof(env->buf) - env->buflen);
 352         if (len >= (sizeof(env->buf) - env->buflen))
 353                 return -ENOMEM;
 354         env->buflen += len;
 355         return 0;
 356 }
 357
 358 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 359 {
 360         struct acpi_device *device = data;
 361
 362         device->driver->ops.notify(device, event);
 363 }
 364
 365 static acpi_status acpi_device_notify_fixed(void *data)
 366 {
 367         struct acpi_device *device = data;
 368
 369         acpi_device_notify(device->handle, ACPI_FIXED_HARDWARE_EVENT, device);
 370         return AE_OK;
 371 }
 372
 373 static int acpi_device_install_notify_handler(struct acpi_device *device)
 374 {
 375         acpi_status status;
 376         char *hid;
 377
 378         hid = acpi_device_hid(device);
 379         if (!strcmp(hid, ACPI_BUTTON_HID_POWERF))
 380                 status =
 381                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 382                                                      acpi_device_notify_fixed,
 383                                                      device);
 384         else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEPF))
 385                 status =
 386                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 387                                                      acpi_device_notify_fixed,
 388                                                      device);
 389         else
 390                 status = acpi_install_notify_handler(device->handle,
 391                                                      ACPI_DEVICE_NOTIFY,
 392                                                      acpi_device_notify,
 393                                                      device);
 394
 395         if (ACPI_FAILURE(status))
 396                 return -EINVAL;
 397         return 0;
 398 }
 399
 400 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 401 {
 402         if (!strcmp(acpi_device_hid(device), ACPI_BUTTON_HID_POWERF))
 403                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 404                                                 acpi_device_notify_fixed);
 405         else if (!strcmp(acpi_device_hid(device), ACPI_BUTTON_HID_SLEEPF))
 406                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 407                                                 acpi_device_notify_fixed);
 408         else
 409                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 410                                            acpi_device_notify);
 411 }
 412
 413 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
 414 static int acpi_start_single_object(struct acpi_device *);
 415 static int acpi_device_probe(struct device * dev)
 416 {
 417         struct acpi_device *acpi_dev = to_acpi_device(dev);
 418         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 419         int ret;
 420
 421         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
 422         if (!ret) {
 423                 if (acpi_dev->bus_ops.acpi_op_start)
 424                         acpi_start_single_object(acpi_dev);
 425
 426                 if (acpi_drv->ops.notify) {
 427                         ret = acpi_device_install_notify_handler(acpi_dev);
 428                         if (ret) {
 429                                 if (acpi_drv->ops.remove)
 430                                         acpi_drv->ops.remove(acpi_dev,
 431                                                      acpi_dev->removal_type);
 432                                 return ret;
 433                         }
 434                 }
 435
 436                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 437                         "Found driver [%s] for device [%s]\n",
 438                         acpi_drv->name, acpi_dev->pnp.bus_id));
 439                 get_device(dev);
 440         }
 441         return ret;
 442 }
 443
 444 static int acpi_device_remove(struct device * dev)
 445 {
 446         struct acpi_device *acpi_dev = to_acpi_device(dev);
 447         struct acpi_driver *acpi_drv = acpi_dev->driver;
 448
 449         if (acpi_drv) {
 450                 if (acpi_drv->ops.notify)
 451                         acpi_device_remove_notify_handler(acpi_dev);
 452                 if (acpi_drv->ops.remove)
 453                         acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
 454         }
 455         acpi_dev->driver = NULL;
 456         acpi_dev->driver_data = NULL;
 457
 458         put_device(dev);
 459         return 0;
 460 }
 461
 462 struct bus_type acpi_bus_type = {
 463         .name           = "acpi",
 464         .suspend        = acpi_device_suspend,
 465         .resume         = acpi_device_resume,
 466         .match          = acpi_bus_match,
 467         .probe          = acpi_device_probe,
 468         .remove         = acpi_device_remove,
 469         .uevent         = acpi_device_uevent,
 470 };
 471
 472 static int acpi_device_register(struct acpi_device *device,
 473                                  struct acpi_device *parent)
 474 {
 475         int result;
 476         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 477         int found = 0;
 478         /*
 479          * Linkage
 480          * -------
 481          * Link this device to its parent and siblings.
 482          */
 483         INIT_LIST_HEAD(&device->children);
 484         INIT_LIST_HEAD(&device->node);
 485         INIT_LIST_HEAD(&device->wakeup_list);
 486
 487         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 488         if (!new_bus_id) {
 489                 printk(KERN_ERR PREFIX "Memory allocation error\n");
 490                 return -ENOMEM;
 491         }
 492
 493         mutex_lock(&acpi_device_lock);
 494         /*
 495          * Find suitable bus_id and instance number in acpi_bus_id_list
 496          * If failed, create one and link it into acpi_bus_id_list
 497          */
 498         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 499                 if(!strcmp(acpi_device_bus_id->bus_id, device->flags.hardware_id? device->pnp.hardware_id : "device")) {
 500                         acpi_device_bus_id->instance_no ++;
 501                         found = 1;
 502                         kfree(new_bus_id);
 503                         break;
 504                 }
 505         }
 506         if (!found) {
 507                 acpi_device_bus_id = new_bus_id;
 508                 strcpy(acpi_device_bus_id->bus_id, device->flags.hardware_id ? device->pnp.hardware_id : "device");
 509                 acpi_device_bus_id->instance_no = 0;
 510                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 511         }
 512         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 513
 514         if (device->parent)
 515                 list_add_tail(&device->node, &device->parent->children);
 516
 517         if (device->wakeup.flags.valid)
 518                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 519         mutex_unlock(&acpi_device_lock);
 520
 521         if (device->parent)
 522                 device->dev.parent = &parent->dev;
 523         device->dev.bus = &acpi_bus_type;
 524         device->dev.release = &acpi_device_release;
 525         result = device_register(&device->dev);
 526         if (result) {
 527                 dev_err(&device->dev, "Error registering device\n");
 528                 goto end;
 529         }
 530
 531         result = acpi_device_setup_files(device);
 532         if (result)
 533                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 534                        dev_name(&device->dev));
 535
 536         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
 537         return 0;
 538 end:
 539         mutex_lock(&acpi_device_lock);
 540         if (device->parent)
 541                 list_del(&device->node);
 542         list_del(&device->wakeup_list);
 543         mutex_unlock(&acpi_device_lock);
 544         return result;
 545 }
 546
 547 static void acpi_device_unregister(struct acpi_device *device, int type)
 548 {
 549         mutex_lock(&acpi_device_lock);
 550         if (device->parent)
 551                 list_del(&device->node);
 552
 553         list_del(&device->wakeup_list);
 554         mutex_unlock(&acpi_device_lock);
 555
 556         acpi_detach_data(device->handle, acpi_bus_data_handler);
 557
 558         acpi_device_remove_files(device);
 559         device_unregister(&device->dev);
 560 }
 561
 562 /* --------------------------------------------------------------------------
 563                                  Driver Management
 564    -------------------------------------------------------------------------- */
 565 /**
 566  * acpi_bus_driver_init - add a device to a driver
 567  * @device: the device to add and initialize
 568  * @driver: driver for the device
 569  *
 570  * Used to initialize a device via its device driver.  Called whenever a
 571  * driver is bound to a device.  Invokes the driver's add() ops.
 572  */
 573 static int
 574 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
 575 {
 576         int result = 0;
 577
 578         if (!device || !driver)
 579                 return -EINVAL;
 580
 581         if (!driver->ops.add)
 582                 return -ENOSYS;
 583
 584         result = driver->ops.add(device);
 585         if (result) {
 586                 device->driver = NULL;
 587                 device->driver_data = NULL;
 588                 return result;
 589         }
 590
 591         device->driver = driver;
 592
 593         /*
 594          * TBD - Configuration Management: Assign resources to device based
 595          * upon possible configuration and currently allocated resources.
 596          */
 597
 598         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 599                           "Driver successfully bound to device\n"));
 600         return 0;
 601 }
 602
 603 static int acpi_start_single_object(struct acpi_device *device)
 604 {
 605         int result = 0;
 606         struct acpi_driver *driver;
 607
 608
 609         if (!(driver = device->driver))
 610                 return 0;
 611
 612         if (driver->ops.start) {
 613                 result = driver->ops.start(device);
 614                 if (result && driver->ops.remove)
 615                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
 616         }
 617
 618         return result;
 619 }
 620
 621 /**
 622  * acpi_bus_register_driver - register a driver with the ACPI bus
 623  * @driver: driver being registered
 624  *
 625  * Registers a driver with the ACPI bus.  Searches the namespace for all
 626  * devices that match the driver's criteria and binds.  Returns zero for
 627  * success or a negative error status for failure.
 628  */
 629 int acpi_bus_register_driver(struct acpi_driver *driver)
 630 {
 631         int ret;
 632
 633         if (acpi_disabled)
 634                 return -ENODEV;
 635         driver->drv.name = driver->name;
 636         driver->drv.bus = &acpi_bus_type;
 637         driver->drv.owner = driver->owner;
 638
 639         ret = driver_register(&driver->drv);
 640         return ret;
 641 }
 642
 643 EXPORT_SYMBOL(acpi_bus_register_driver);
 644
 645 /**
 646  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
 647  * @driver: driver to unregister
 648  *
 649  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
 650  * devices that match the driver's criteria and unbinds.
 651  */
 652 void acpi_bus_unregister_driver(struct acpi_driver *driver)
 653 {
 654         driver_unregister(&driver->drv);
 655 }
 656
 657 EXPORT_SYMBOL(acpi_bus_unregister_driver);
 658
 659 /* --------------------------------------------------------------------------
 660                                  Device Enumeration
 661    -------------------------------------------------------------------------- */
 662 acpi_status
 663 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 664 {
 665         acpi_status status;
 666         acpi_handle tmp;
 667         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 668         union acpi_object *obj;
 669
 670         status = acpi_get_handle(handle, "_EJD", &tmp);
 671         if (ACPI_FAILURE(status))
 672                 return status;
 673
 674         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 675         if (ACPI_SUCCESS(status)) {
 676                 obj = buffer.pointer;
 677                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 678                                          ejd);
 679                 kfree(buffer.pointer);
 680         }
 681         return status;
 682 }
 683 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 684
 685 void acpi_bus_data_handler(acpi_handle handle, u32 function, void *context)
 686 {
 687
 688         /* TBD */
 689
 690         return;
 691 }
 692
 693 static int acpi_bus_get_perf_flags(struct acpi_device *device)
 694 {
 695         device->performance.state = ACPI_STATE_UNKNOWN;
 696         return 0;
 697 }
 698
 699 static acpi_status
 700 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
 701                                              union acpi_object *package)
 702 {
 703         int i = 0;
 704         union acpi_object *element = NULL;
 705
 706         if (!device || !package || (package->package.count < 2))
 707                 return AE_BAD_PARAMETER;
 708
 709         element = &(package->package.elements[0]);
 710         if (!element)
 711                 return AE_BAD_PARAMETER;
 712         if (element->type == ACPI_TYPE_PACKAGE) {
 713                 if ((element->package.count < 2) ||
 714                     (element->package.elements[0].type !=
 715                      ACPI_TYPE_LOCAL_REFERENCE)
 716                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 717                         return AE_BAD_DATA;
 718                 device->wakeup.gpe_device =
 719                     element->package.elements[0].reference.handle;
 720                 device->wakeup.gpe_number =
 721                     (u32) element->package.elements[1].integer.value;
 722         } else if (element->type == ACPI_TYPE_INTEGER) {
 723                 device->wakeup.gpe_number = element->integer.value;
 724         } else
 725                 return AE_BAD_DATA;
 726
 727         element = &(package->package.elements[1]);
 728         if (element->type != ACPI_TYPE_INTEGER) {
 729                 return AE_BAD_DATA;
 730         }
 731         device->wakeup.sleep_state = element->integer.value;
 732
 733         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
 734                 return AE_NO_MEMORY;
 735         }
 736         device->wakeup.resources.count = package->package.count - 2;
 737         for (i = 0; i < device->wakeup.resources.count; i++) {
 738                 element = &(package->package.elements[i + 2]);
 739                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
 740                         return AE_BAD_DATA;
 741
 742                 device->wakeup.resources.handles[i] = element->reference.handle;
 743         }
 744
 745         return AE_OK;
 746 }
 747
 748 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 749 {
 750         acpi_status status = 0;
 751         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 752         union acpi_object *package = NULL;
 753         int psw_error;
 754
 755         struct acpi_device_id button_device_ids[] = {
 756                 {"PNP0C0D", 0},
 757                 {"PNP0C0C", 0},
 758                 {"PNP0C0E", 0},
 759                 {"", 0},
 760         };
 761
 762         /* _PRW */
 763         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
 764         if (ACPI_FAILURE(status)) {
 765                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 766                 goto end;
 767         }
 768
 769         package = (union acpi_object *)buffer.pointer;
 770         status = acpi_bus_extract_wakeup_device_power_package(device, package);
 771         if (ACPI_FAILURE(status)) {
 772                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
 773                 goto end;
 774         }
 775
 776         kfree(buffer.pointer);
 777
 778         device->wakeup.flags.valid = 1;
 779         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
 780          * system for the ACPI device with the _PRW object.
 781          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 782          * So it is necessary to call _DSW object first. Only when it is not
 783          * present will the _PSW object used.
 784          */
 785         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
 786         if (psw_error)
 787                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 788                                 "error in _DSW or _PSW evaluation\n"));
 789
 790         /* Power button, Lid switch always enable wakeup */
 791         if (!acpi_match_device_ids(device, button_device_ids))
 792                 device->wakeup.flags.run_wake = 1;
 793
 794 end:
 795         if (ACPI_FAILURE(status))
 796                 device->flags.wake_capable = 0;
 797         return 0;
 798 }
 799
 800 static int acpi_bus_get_power_flags(struct acpi_device *device)
 801 {
 802         acpi_status status = 0;
 803         acpi_handle handle = NULL;
 804         u32 i = 0;
 805
 806
 807         /*
 808          * Power Management Flags
 809          */
 810         status = acpi_get_handle(device->handle, "_PSC", &handle);
 811         if (ACPI_SUCCESS(status))
 812                 device->power.flags.explicit_get = 1;
 813         status = acpi_get_handle(device->handle, "_IRC", &handle);
 814         if (ACPI_SUCCESS(status))
 815                 device->power.flags.inrush_current = 1;
 816
 817         /*
 818          * Enumerate supported power management states
 819          */
 820         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
 821                 struct acpi_device_power_state *ps = &device->power.states[i];
 822                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
 823
 824                 /* Evaluate "_PRx" to se if power resources are referenced */
 825                 acpi_evaluate_reference(device->handle, object_name, NULL,
 826                                         &ps->resources);
 827                 if (ps->resources.count) {
 828                         device->power.flags.power_resources = 1;
 829                         ps->flags.valid = 1;
 830                 }
 831
 832                 /* Evaluate "_PSx" to see if we can do explicit sets */
 833                 object_name[2] = 'S';
 834                 status = acpi_get_handle(device->handle, object_name, &handle);
 835                 if (ACPI_SUCCESS(status)) {
 836                         ps->flags.explicit_set = 1;
 837                         ps->flags.valid = 1;
 838                 }
 839
 840                 /* State is valid if we have some power control */
 841                 if (ps->resources.count || ps->flags.explicit_set)
 842                         ps->flags.valid = 1;
 843
 844                 ps->power = -1; /* Unknown - driver assigned */
 845                 ps->latency = -1;       /* Unknown - driver assigned */
 846         }
 847
 848         /* Set defaults for D0 and D3 states (always valid) */
 849         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 850         device->power.states[ACPI_STATE_D0].power = 100;
 851         device->power.states[ACPI_STATE_D3].flags.valid = 1;
 852         device->power.states[ACPI_STATE_D3].power = 0;
 853
 854         /* TBD: System wake support and resource requirements. */
 855
 856         device->power.state = ACPI_STATE_UNKNOWN;
 857         acpi_bus_get_power(device->handle, &(device->power.state));
 858
 859         return 0;
 860 }
 861
 862 static int acpi_bus_get_flags(struct acpi_device *device)
 863 {
 864         acpi_status status = AE_OK;
 865         acpi_handle temp = NULL;
 866
 867
 868         /* Presence of _STA indicates 'dynamic_status' */
 869         status = acpi_get_handle(device->handle, "_STA", &temp);
 870         if (ACPI_SUCCESS(status))
 871                 device->flags.dynamic_status = 1;
 872
 873         /* Presence of _CID indicates 'compatible_ids' */
 874         status = acpi_get_handle(device->handle, "_CID", &temp);
 875         if (ACPI_SUCCESS(status))
 876                 device->flags.compatible_ids = 1;
 877
 878         /* Presence of _RMV indicates 'removable' */
 879         status = acpi_get_handle(device->handle, "_RMV", &temp);
 880         if (ACPI_SUCCESS(status))
 881                 device->flags.removable = 1;
 882
 883         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 884         status = acpi_get_handle(device->handle, "_EJD", &temp);
 885         if (ACPI_SUCCESS(status))
 886                 device->flags.ejectable = 1;
 887         else {
 888                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
 889                 if (ACPI_SUCCESS(status))
 890                         device->flags.ejectable = 1;
 891         }
 892
 893         /* Presence of _LCK indicates 'lockable' */
 894         status = acpi_get_handle(device->handle, "_LCK", &temp);
 895         if (ACPI_SUCCESS(status))
 896                 device->flags.lockable = 1;
 897
 898         /* Presence of _PS0|_PR0 indicates 'power manageable' */
 899         status = acpi_get_handle(device->handle, "_PS0", &temp);
 900         if (ACPI_FAILURE(status))
 901                 status = acpi_get_handle(device->handle, "_PR0", &temp);
 902         if (ACPI_SUCCESS(status))
 903                 device->flags.power_manageable = 1;
 904
 905         /* Presence of _PRW indicates wake capable */
 906         status = acpi_get_handle(device->handle, "_PRW", &temp);
 907         if (ACPI_SUCCESS(status))
 908                 device->flags.wake_capable = 1;
 909
 910         /* TBD: Performance management */
 911
 912         return 0;
 913 }
 914
 915 static void acpi_device_get_busid(struct acpi_device *device,
 916                                   acpi_handle handle, int type)
 917 {
 918         char bus_id[5] = { '?', 0 };
 919         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
 920         int i = 0;
 921
 922         /*
 923          * Bus ID
 924          * ------
 925          * The device's Bus ID is simply the object name.
 926          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
 927          */
 928         switch (type) {
 929         case ACPI_BUS_TYPE_SYSTEM:
 930                 strcpy(device->pnp.bus_id, "ACPI");
 931                 break;
 932         case ACPI_BUS_TYPE_POWER_BUTTON:
 933                 strcpy(device->pnp.bus_id, "PWRF");
 934                 break;
 935         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 936                 strcpy(device->pnp.bus_id, "SLPF");
 937                 break;
 938         default:
 939                 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 940                 /* Clean up trailing underscores (if any) */
 941                 for (i = 3; i > 1; i--) {
 942                         if (bus_id[i] == '_')
 943                                 bus_id[i] = '\0';
 944                         else
 945                                 break;
 946                 }
 947                 strcpy(device->pnp.bus_id, bus_id);
 948                 break;
 949         }
 950 }
 951
 952 /*
 953  * acpi_bay_match - see if a device is an ejectable driver bay
 954  *
 955  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
 956  * then we can safely call it an ejectable drive bay
 957  */
 958 static int acpi_bay_match(struct acpi_device *device){
 959         acpi_status status;
 960         acpi_handle handle;
 961         acpi_handle tmp;
 962         acpi_handle phandle;
 963
 964         handle = device->handle;
 965
 966         status = acpi_get_handle(handle, "_EJ0", &tmp);
 967         if (ACPI_FAILURE(status))
 968                 return -ENODEV;
 969
 970         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
 971                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
 972                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
 973                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
 974                 return 0;
 975
 976         if (acpi_get_parent(handle, &phandle))
 977                 return -ENODEV;
 978
 979         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
 980                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
 981                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
 982                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
 983                 return 0;
 984
 985         return -ENODEV;
 986 }
 987
 988 /*
 989  * acpi_dock_match - see if a device has a _DCK method
 990  */
 991 static int acpi_dock_match(struct acpi_device *device)
 992 {
 993         acpi_handle tmp;
 994         return acpi_get_handle(device->handle, "_DCK", &tmp);
 995 }
 996
 997 static void acpi_device_set_id(struct acpi_device *device,
 998                                struct acpi_device *parent, acpi_handle handle,
 999                                int type)
1000 {
1001         struct acpi_device_info *info;
1002         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1003         char *hid = NULL;
1004         char *uid = NULL;
1005         struct acpi_compatible_id_list *cid_list = NULL;
1006         const char *cid_add = NULL;
1007         acpi_status status;
1008
1009         switch (type) {
1010         case ACPI_BUS_TYPE_DEVICE:
1011                 status = acpi_get_object_info(handle, &buffer);
1012                 if (ACPI_FAILURE(status)) {
1013                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1014                         return;
1015                 }
1016
1017                 info = buffer.pointer;
1018                 if (info->valid & ACPI_VALID_HID)
1019                         hid = info->hardware_id.value;
1020                 if (info->valid & ACPI_VALID_UID)
1021                         uid = info->unique_id.value;
1022                 if (info->valid & ACPI_VALID_CID)
1023                         cid_list = &info->compatibility_id;
1024                 if (info->valid & ACPI_VALID_ADR) {
1025                         device->pnp.bus_address = info->address;
1026                         device->flags.bus_address = 1;
1027                 }
1028
1029                 /* If we have a video/bay/dock device, add our selfdefined
1030                    HID to the CID list. Like that the video/bay/dock drivers
1031                    will get autoloaded and the device might still match
1032                    against another driver.
1033                 */
1034                 if (acpi_is_video_device(device))
1035                         cid_add = ACPI_VIDEO_HID;
1036                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1037                         cid_add = ACPI_BAY_HID;
1038                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1039                         cid_add = ACPI_DOCK_HID;
1040
1041                 break;
1042         case ACPI_BUS_TYPE_POWER:
1043                 hid = ACPI_POWER_HID;
1044                 break;
1045         case ACPI_BUS_TYPE_PROCESSOR:
1046                 hid = ACPI_PROCESSOR_OBJECT_HID;
1047                 break;
1048         case ACPI_BUS_TYPE_SYSTEM:
1049                 hid = ACPI_SYSTEM_HID;
1050                 break;
1051         case ACPI_BUS_TYPE_THERMAL:
1052                 hid = ACPI_THERMAL_HID;
1053                 break;
1054         case ACPI_BUS_TYPE_POWER_BUTTON:
1055                 hid = ACPI_BUTTON_HID_POWERF;
1056                 break;
1057         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1058                 hid = ACPI_BUTTON_HID_SLEEPF;
1059                 break;
1060         }
1061
1062         /*
1063          * \_SB
1064          * ----
1065          * Fix for the system root bus device -- the only root-level device.
1066          */
1067         if (((acpi_handle)parent == ACPI_ROOT_OBJECT) && (type == ACPI_BUS_TYPE_DEVICE)) {
1068                 hid = ACPI_BUS_HID;
1069                 strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1070                 strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1071         }
1072
1073         if (hid) {
1074                 strcpy(device->pnp.hardware_id, hid);
1075                 device->flags.hardware_id = 1;
1076         }
1077         if (uid) {
1078                 strcpy(device->pnp.unique_id, uid);
1079                 device->flags.unique_id = 1;
1080         }
1081         if (cid_list || cid_add) {
1082                 struct  acpi_compatible_id_list *list;
1083                 int size = 0;
1084                 int count = 0;
1085
1086                 if (cid_list) {
1087                         size = cid_list->size;
1088                 } else if (cid_add) {
1089                         size = sizeof(struct acpi_compatible_id_list);
1090                         cid_list = ACPI_ALLOCATE_ZEROED((acpi_size) size);
1091                         if (!cid_list) {
1092                                 printk(KERN_ERR "Memory allocation error\n");
1093                                 kfree(buffer.pointer);
1094                                 return;
1095                         } else {
1096                                 cid_list->count = 0;
1097                                 cid_list->size = size;
1098                         }
1099                 }
1100                 if (cid_add)
1101                         size += sizeof(struct acpi_compatible_id);
1102                 list = kmalloc(size, GFP_KERNEL);
1103
1104                 if (list) {
1105                         if (cid_list) {
1106                                 memcpy(list, cid_list, cid_list->size);
1107                                 count = cid_list->count;
1108                         }
1109                         if (cid_add) {
1110                                 strncpy(list->id[count].value, cid_add,
1111                                         ACPI_MAX_CID_LENGTH);
1112                                 count++;
1113                                 device->flags.compatible_ids = 1;
1114                         }
1115                         list->size = size;
1116                         list->count = count;
1117                         device->pnp.cid_list = list;
1118                 } else
1119                         printk(KERN_ERR PREFIX "Memory allocation error\n");
1120         }
1121
1122         kfree(buffer.pointer);
1123 }
1124
1125 static int acpi_device_set_context(struct acpi_device *device, int type)
1126 {
1127         acpi_status status = AE_OK;
1128         int result = 0;
1129         /*
1130          * Context
1131          * -------
1132          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1133          * resolutions from handle->device very efficient.  Note that we need
1134          * to be careful with fixed-feature devices as they all attach to the
1135          * root object.
1136          */
1137         if (type != ACPI_BUS_TYPE_POWER_BUTTON &&
1138             type != ACPI_BUS_TYPE_SLEEP_BUTTON) {
1139                 status = acpi_attach_data(device->handle,
1140                                           acpi_bus_data_handler, device);
1141
1142                 if (ACPI_FAILURE(status)) {
1143                         printk(KERN_ERR PREFIX "Error attaching device data\n");
1144                         result = -ENODEV;
1145                 }
1146         }
1147         return result;
1148 }
1149
1150 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1151 {
1152         if (!dev)
1153                 return -EINVAL;
1154
1155         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1156         device_release_driver(&dev->dev);
1157
1158         if (!rmdevice)
1159                 return 0;
1160
1161         /*
1162          * unbind _ADR-Based Devices when hot removal
1163          */
1164         if (dev->flags.bus_address) {
1165                 if ((dev->parent) && (dev->parent->ops.unbind))
1166                         dev->parent->ops.unbind(dev);
1167         }
1168         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1169
1170         return 0;
1171 }
1172
1173 static int
1174 acpi_add_single_object(struct acpi_device **child,
1175                        struct acpi_device *parent, acpi_handle handle, int type,
1176                         struct acpi_bus_ops *ops)
1177 {
1178         int result = 0;
1179         struct acpi_device *device = NULL;
1180
1181
1182         if (!child)
1183                 return -EINVAL;
1184
1185         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1186         if (!device) {
1187                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1188                 return -ENOMEM;
1189         }
1190
1191         device->handle = handle;
1192         device->parent = parent;
1193         device->bus_ops = *ops; /* workround for not call .start */
1194
1195
1196         acpi_device_get_busid(device, handle, type);
1197
1198         /*
1199          * Flags
1200          * -----
1201          * Get prior to calling acpi_bus_get_status() so we know whether
1202          * or not _STA is present.  Note that we only look for object
1203          * handles -- cannot evaluate objects until we know the device is
1204          * present and properly initialized.
1205          */
1206         result = acpi_bus_get_flags(device);
1207         if (result)
1208                 goto end;
1209
1210         /*
1211          * Status
1212          * ------
1213          * See if the device is present.  We always assume that non-Device
1214          * and non-Processor objects (e.g. thermal zones, power resources,
1215          * etc.) are present, functioning, etc. (at least when parent object
1216          * is present).  Note that _STA has a different meaning for some
1217          * objects (e.g. power resources) so we need to be careful how we use
1218          * it.
1219          */
1220         switch (type) {
1221         case ACPI_BUS_TYPE_PROCESSOR:
1222         case ACPI_BUS_TYPE_DEVICE:
1223                 result = acpi_bus_get_status(device);
1224                 if (ACPI_FAILURE(result)) {
1225                         result = -ENODEV;
1226                         goto end;
1227                 }
1228                 /*
1229                  * When the device is neither present nor functional, the
1230                  * device should not be added to Linux ACPI device tree.
1231                  * When the status of the device is not present but functinal,
1232                  * it should be added to Linux ACPI tree. For example : bay
1233                  * device , dock device.
1234                  * In such conditions it is unncessary to check whether it is
1235                  * bay device or dock device.
1236                  */
1237                 if (!device->status.present && !device->status.functional) {
1238                         result = -ENODEV;
1239                         goto end;
1240                 }
1241                 break;
1242         default:
1243                 STRUCT_TO_INT(device->status) =
1244                     ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
1245                     ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
1246                 break;
1247         }
1248
1249         /*
1250          * Initialize Device
1251          * -----------------
1252          * TBD: Synch with Core's enumeration/initialization process.
1253          */
1254
1255         /*
1256          * Hardware ID, Unique ID, & Bus Address
1257          * -------------------------------------
1258          */
1259         acpi_device_set_id(device, parent, handle, type);
1260
1261         /*
1262          * The ACPI device is attached to acpi handle before getting
1263          * the power/wakeup/peformance flags. Otherwise OS can't get
1264          * the corresponding ACPI device by the acpi handle in the course
1265          * of getting the power/wakeup/performance flags.
1266          */
1267         result = acpi_device_set_context(device, type);
1268         if (result)
1269                 goto end;
1270
1271         /*
1272          * Power Management
1273          * ----------------
1274          */
1275         if (device->flags.power_manageable) {
1276                 result = acpi_bus_get_power_flags(device);
1277                 if (result)
1278                         goto end;
1279         }
1280
1281         /*
1282          * Wakeup device management
1283          *-----------------------
1284          */
1285         if (device->flags.wake_capable) {
1286                 result = acpi_bus_get_wakeup_device_flags(device);
1287                 if (result)
1288                         goto end;
1289         }
1290
1291         /*
1292          * Performance Management
1293          * ----------------------
1294          */
1295         if (device->flags.performance_manageable) {
1296                 result = acpi_bus_get_perf_flags(device);
1297                 if (result)
1298                         goto end;
1299         }
1300
1301
1302         result = acpi_device_register(device, parent);
1303
1304         /*
1305          * Bind _ADR-Based Devices when hot add
1306          */
1307         if (device->flags.bus_address) {
1308                 if (device->parent && device->parent->ops.bind)
1309                         device->parent->ops.bind(device);
1310         }
1311
1312 end:
1313         if (!result)
1314                 *child = device;
1315         else {
1316                 kfree(device->pnp.cid_list);
1317                 kfree(device);
1318         }
1319
1320         return result;
1321 }
1322
1323 static int acpi_bus_scan(struct acpi_device *start, struct acpi_bus_ops *ops)
1324 {
1325         acpi_status status = AE_OK;
1326         struct acpi_device *parent = NULL;
1327         struct acpi_device *child = NULL;
1328         acpi_handle phandle = NULL;
1329         acpi_handle chandle = NULL;
1330         acpi_object_type type = 0;
1331         u32 level = 1;
1332
1333
1334         if (!start)
1335                 return -EINVAL;
1336
1337         parent = start;
1338         phandle = start->handle;
1339
1340         /*
1341          * Parse through the ACPI namespace, identify all 'devices', and
1342          * create a new 'struct acpi_device' for each.
1343          */
1344         while ((level > 0) && parent) {
1345
1346                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1347                                               chandle, &chandle);
1348
1349                 /*
1350                  * If this scope is exhausted then move our way back up.
1351                  */
1352                 if (ACPI_FAILURE(status)) {
1353                         level--;
1354                         chandle = phandle;
1355                         acpi_get_parent(phandle, &phandle);
1356                         if (parent->parent)
1357                                 parent = parent->parent;
1358                         continue;
1359                 }
1360
1361                 status = acpi_get_type(chandle, &type);
1362                 if (ACPI_FAILURE(status))
1363                         continue;
1364
1365                 /*
1366                  * If this is a scope object then parse it (depth-first).
1367                  */
1368                 if (type == ACPI_TYPE_LOCAL_SCOPE) {
1369                         level++;
1370                         phandle = chandle;
1371                         chandle = NULL;
1372                         continue;
1373                 }
1374
1375                 /*
1376                  * We're only interested in objects that we consider 'devices'.
1377                  */
1378                 switch (type) {
1379                 case ACPI_TYPE_DEVICE:
1380                         type = ACPI_BUS_TYPE_DEVICE;
1381                         break;
1382                 case ACPI_TYPE_PROCESSOR:
1383                         type = ACPI_BUS_TYPE_PROCESSOR;
1384                         break;
1385                 case ACPI_TYPE_THERMAL:
1386                         type = ACPI_BUS_TYPE_THERMAL;
1387                         break;
1388                 case ACPI_TYPE_POWER:
1389                         type = ACPI_BUS_TYPE_POWER;
1390                         break;
1391                 default:
1392                         continue;
1393                 }
1394
1395                 if (ops->acpi_op_add)
1396                         status = acpi_add_single_object(&child, parent,
1397                                 chandle, type, ops);
1398                 else
1399                         status = acpi_bus_get_device(chandle, &child);
1400
1401                 if (ACPI_FAILURE(status))
1402                         continue;
1403
1404                 if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1405                         status = acpi_start_single_object(child);
1406                         if (ACPI_FAILURE(status))
1407                                 continue;
1408                 }
1409
1410                 /*
1411                  * If the device is present, enabled, and functioning then
1412                  * parse its scope (depth-first).  Note that we need to
1413                  * represent absent devices to facilitate PnP notifications
1414                  * -- but only the subtree head (not all of its children,
1415                  * which will be enumerated when the parent is inserted).
1416                  *
1417                  * TBD: Need notifications and other detection mechanisms
1418                  *      in place before we can fully implement this.
1419                  */
1420                  /*
1421                  * When the device is not present but functional, it is also
1422                  * necessary to scan the children of this device.
1423                  */
1424                 if (child->status.present || (!child->status.present &&
1425                                         child->status.functional)) {
1426                         status = acpi_get_next_object(ACPI_TYPE_ANY, chandle,
1427                                                       NULL, NULL);
1428                         if (ACPI_SUCCESS(status)) {
1429                                 level++;
1430                                 phandle = chandle;
1431                                 chandle = NULL;
1432                                 parent = child;
1433                         }
1434                 }
1435         }
1436
1437         return 0;
1438 }
1439
1440 int
1441 acpi_bus_add(struct acpi_device **child,
1442              struct acpi_device *parent, acpi_handle handle, int type)
1443 {
1444         int result;
1445         struct acpi_bus_ops ops;
1446
1447         memset(&ops, 0, sizeof(ops));
1448         ops.acpi_op_add = 1;
1449
1450         result = acpi_add_single_object(child, parent, handle, type, &ops);
1451         if (!result)
1452                 result = acpi_bus_scan(*child, &ops);
1453
1454         return result;
1455 }
1456 EXPORT_SYMBOL(acpi_bus_add);
1457
1458 int acpi_bus_start(struct acpi_device *device)
1459 {
1460         int result;
1461         struct acpi_bus_ops ops;
1462
1463
1464         if (!device)
1465                 return -EINVAL;
1466
1467         result = acpi_start_single_object(device);
1468         if (!result) {
1469                 memset(&ops, 0, sizeof(ops));
1470                 ops.acpi_op_start = 1;
1471                 result = acpi_bus_scan(device, &ops);
1472         }
1473         return result;
1474 }
1475 EXPORT_SYMBOL(acpi_bus_start);
1476
1477 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1478 {
1479         acpi_status status;
1480         struct acpi_device *parent, *child;
1481         acpi_handle phandle, chandle;
1482         acpi_object_type type;
1483         u32 level = 1;
1484         int err = 0;
1485
1486         parent = start;
1487         phandle = start->handle;
1488         child = chandle = NULL;
1489
1490         while ((level > 0) && parent && (!err)) {
1491                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1492                                               chandle, &chandle);
1493
1494                 /*
1495                  * If this scope is exhausted then move our way back up.
1496                  */
1497                 if (ACPI_FAILURE(status)) {
1498                         level--;
1499                         chandle = phandle;
1500                         acpi_get_parent(phandle, &phandle);
1501                         child = parent;
1502                         parent = parent->parent;
1503
1504                         if (level == 0)
1505                                 err = acpi_bus_remove(child, rmdevice);
1506                         else
1507                                 err = acpi_bus_remove(child, 1);
1508
1509                         continue;
1510                 }
1511
1512                 status = acpi_get_type(chandle, &type);
1513                 if (ACPI_FAILURE(status)) {
1514                         continue;
1515                 }
1516                 /*
1517                  * If there is a device corresponding to chandle then
1518                  * parse it (depth-first).
1519                  */
1520                 if (acpi_bus_get_device(chandle, &child) == 0) {
1521                         level++;
1522                         phandle = chandle;
1523                         chandle = NULL;
1524                         parent = child;
1525                 }
1526                 continue;
1527         }
1528         return err;
1529 }
1530 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1531
1532 static int acpi_bus_scan_fixed(struct acpi_device *root)
1533 {
1534         int result = 0;
1535         struct acpi_device *device = NULL;
1536         struct acpi_bus_ops ops;
1537
1538         if (!root)
1539                 return -ENODEV;
1540
1541         memset(&ops, 0, sizeof(ops));
1542         ops.acpi_op_add = 1;
1543         ops.acpi_op_start = 1;
1544
1545         /*
1546          * Enumerate all fixed-feature devices.
1547          */
1548         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1549                 result = acpi_add_single_object(&device, acpi_root,
1550                                                 NULL,
1551                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1552                                                 &ops);
1553         }
1554
1555         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1556                 result = acpi_add_single_object(&device, acpi_root,
1557                                                 NULL,
1558                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1559                                                 &ops);
1560         }
1561
1562         return result;
1563 }
1564
1565 int __init acpi_scan_init(void)
1566 {
1567         int result;
1568         struct acpi_bus_ops ops;
1569
1570         memset(&ops, 0, sizeof(ops));
1571         ops.acpi_op_add = 1;
1572         ops.acpi_op_start = 1;
1573
1574         result = bus_register(&acpi_bus_type);
1575         if (result) {
1576                 /* We don't want to quit even if we failed to add suspend/resume */
1577                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1578         }
1579
1580         /*
1581          * Create the root device in the bus's device tree
1582          */
1583         result = acpi_add_single_object(&acpi_root, NULL, ACPI_ROOT_OBJECT,
1584                                         ACPI_BUS_TYPE_SYSTEM, &ops);
1585         if (result)
1586                 goto Done;
1587
1588         /*
1589          * Enumerate devices in the ACPI namespace.
1590          */
1591         result = acpi_bus_scan_fixed(acpi_root);
1592
1593         if (!result)
1594                 result = acpi_bus_scan(acpi_root, &ops);
1595
1596         if (result)
1597                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1598
1599 Done:
1600         return result;
1601 }