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 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
  26
  27 static LIST_HEAD(acpi_device_list);
  28 static LIST_HEAD(acpi_bus_id_list);
  29 DEFINE_MUTEX(acpi_device_lock);
  30 LIST_HEAD(acpi_wakeup_device_list);
  31
  32 struct acpi_device_bus_id{
  33         char bus_id[15];
  34         unsigned int instance_no;
  35         struct list_head node;
  36 };
  37
  38 /*
  39  * Creates hid/cid(s) string needed for modalias and uevent
  40  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
  41  * char *modalias: "acpi:IBM0001:ACPI0001"
  42 */
  43 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
  44                            int size)
  45 {
  46         int len;
  47         int count;
  48         struct acpi_hardware_id *id;
  49
  50         len = snprintf(modalias, size, "acpi:");
  51         size -= len;
  52
  53         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
  54                 count = snprintf(&modalias[len], size, "%s:", id->id);
  55                 if (count < 0 || count >= size)
  56                         return -EINVAL;
  57                 len += count;
  58                 size -= count;
  59         }
  60
  61         modalias[len] = '\0';
  62         return len;
  63 }
  64
  65 static ssize_t
  66 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
  67         struct acpi_device *acpi_dev = to_acpi_device(dev);
  68         int len;
  69
  70         /* Device has no HID and no CID or string is >1024 */
  71         len = create_modalias(acpi_dev, buf, 1024);
  72         if (len <= 0)
  73                 return 0;
  74         buf[len++] = '\n';
  75         return len;
  76 }
  77 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
  78
  79 static void acpi_bus_hot_remove_device(void *context)
  80 {
  81         struct acpi_device *device;
  82         acpi_handle handle = context;
  83         struct acpi_object_list arg_list;
  84         union acpi_object arg;
  85         acpi_status status = AE_OK;
  86
  87         if (acpi_bus_get_device(handle, &device))
  88                 return;
  89
  90         if (!device)
  91                 return;
  92
  93         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
  94                 "Hot-removing device %s...\n", dev_name(&device->dev)));
  95
  96         if (acpi_bus_trim(device, 1)) {
  97                 printk(KERN_ERR PREFIX
  98                                 "Removing device failed\n");
  99                 return;
 100         }
 101
 102         /* power off device */
 103         status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
 104         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
 105                 printk(KERN_WARNING PREFIX
 106                                 "Power-off device failed\n");
 107
 108         if (device->flags.lockable) {
 109                 arg_list.count = 1;
 110                 arg_list.pointer = &arg;
 111                 arg.type = ACPI_TYPE_INTEGER;
 112                 arg.integer.value = 0;
 113                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
 114         }
 115
 116         arg_list.count = 1;
 117         arg_list.pointer = &arg;
 118         arg.type = ACPI_TYPE_INTEGER;
 119         arg.integer.value = 1;
 120
 121         /*
 122          * TBD: _EJD support.
 123          */
 124         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
 125         if (ACPI_FAILURE(status))
 126                 printk(KERN_WARNING PREFIX
 127                                 "Eject device failed\n");
 128
 129         return;
 130 }
 131
 132 static ssize_t
 133 acpi_eject_store(struct device *d, struct device_attribute *attr,
 134                 const char *buf, size_t count)
 135 {
 136         int ret = count;
 137         acpi_status status;
 138         acpi_object_type type = 0;
 139         struct acpi_device *acpi_device = to_acpi_device(d);
 140
 141         if ((!count) || (buf[0] != '1')) {
 142                 return -EINVAL;
 143         }
 144 #ifndef FORCE_EJECT
 145         if (acpi_device->driver == NULL) {
 146                 ret = -ENODEV;
 147                 goto err;
 148         }
 149 #endif
 150         status = acpi_get_type(acpi_device->handle, &type);
 151         if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
 152                 ret = -ENODEV;
 153                 goto err;
 154         }
 155
 156         acpi_os_hotplug_execute(acpi_bus_hot_remove_device, acpi_device->handle);
 157 err:
 158         return ret;
 159 }
 160
 161 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 162
 163 static ssize_t
 164 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 165         struct acpi_device *acpi_dev = to_acpi_device(dev);
 166
 167         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
 168 }
 169 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 170
 171 #ifdef CONFIG_PCI_GUESTDEV
 172 static ssize_t
 173 acpi_device_uid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 174         struct acpi_device *acpi_dev = to_acpi_device(dev);
 175
 176         return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
 177 }
 178 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
 179 #endif
 180
 181 static ssize_t
 182 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 183         struct acpi_device *acpi_dev = to_acpi_device(dev);
 184         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 185         int result;
 186
 187         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 188         if (result)
 189                 goto end;
 190
 191         result = sprintf(buf, "%s\n", (char*)path.pointer);
 192         kfree(path.pointer);
 193 end:
 194         return result;
 195 }
 196 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 197
 198 static int acpi_device_setup_files(struct acpi_device *dev)
 199 {
 200         acpi_status status;
 201         acpi_handle temp;
 202         int result = 0;
 203
 204         /*
 205          * Devices gotten from FADT don't have a "path" attribute
 206          */
 207         if (dev->handle) {
 208                 result = device_create_file(&dev->dev, &dev_attr_path);
 209                 if (result)
 210                         goto end;
 211         }
 212
 213         result = device_create_file(&dev->dev, &dev_attr_hid);
 214         if (result)
 215                 goto end;
 216
 217         result = device_create_file(&dev->dev, &dev_attr_modalias);
 218         if (result)
 219                 goto end;
 220
 221 #ifdef CONFIG_PCI_GUESTDEV
 222         if(dev->pnp.unique_id) {
 223                 result = device_create_file(&dev->dev, &dev_attr_uid);
 224                 if(result)
 225                         goto end;
 226         }
 227 #endif
 228         /*
 229          * If device has _EJ0, 'eject' file is created that is used to trigger
 230          * hot-removal function from userland.
 231          */
 232         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 233         if (ACPI_SUCCESS(status))
 234                 result = device_create_file(&dev->dev, &dev_attr_eject);
 235 end:
 236         return result;
 237 }
 238
 239 static void acpi_device_remove_files(struct acpi_device *dev)
 240 {
 241         acpi_status status;
 242         acpi_handle temp;
 243
 244         /*
 245          * If device has _EJ0, 'eject' file is created that is used to trigger
 246          * hot-removal function from userland.
 247          */
 248         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 249         if (ACPI_SUCCESS(status))
 250                 device_remove_file(&dev->dev, &dev_attr_eject);
 251
 252         device_remove_file(&dev->dev, &dev_attr_modalias);
 253         device_remove_file(&dev->dev, &dev_attr_hid);
 254         if (dev->handle)
 255                 device_remove_file(&dev->dev, &dev_attr_path);
 256 }
 257 /* --------------------------------------------------------------------------
 258                         ACPI Bus operations
 259    -------------------------------------------------------------------------- */
 260
 261 int acpi_match_device_ids(struct acpi_device *device,
 262                           const struct acpi_device_id *ids)
 263 {
 264         const struct acpi_device_id *id;
 265         struct acpi_hardware_id *hwid;
 266
 267         /*
 268          * If the device is not present, it is unnecessary to load device
 269          * driver for it.
 270          */
 271         if (!device->status.present)
 272                 return -ENODEV;
 273
 274         for (id = ids; id->id[0]; id++)
 275                 list_for_each_entry(hwid, &device->pnp.ids, list)
 276                         if (!strcmp((char *) id->id, hwid->id))
 277                                 return 0;
 278
 279         return -ENOENT;
 280 }
 281 EXPORT_SYMBOL(acpi_match_device_ids);
 282
 283 static void acpi_free_ids(struct acpi_device *device)
 284 {
 285         struct acpi_hardware_id *id, *tmp;
 286
 287         list_for_each_entry_safe(id, tmp, &device->pnp.ids, list) {
 288                 kfree(id->id);
 289                 kfree(id);
 290         }
 291 #ifdef CONFIG_PCI_GUESTDEV
 292         kfree(device->pnp.unique_id);
 293 #endif
 294 }
 295
 296 static void acpi_device_release(struct device *dev)
 297 {
 298         struct acpi_device *acpi_dev = to_acpi_device(dev);
 299
 300         acpi_free_ids(acpi_dev);
 301         kfree(acpi_dev);
 302 }
 303
 304 static int acpi_device_suspend(struct device *dev, pm_message_t state)
 305 {
 306         struct acpi_device *acpi_dev = to_acpi_device(dev);
 307         struct acpi_driver *acpi_drv = acpi_dev->driver;
 308
 309         if (acpi_drv && acpi_drv->ops.suspend)
 310                 return acpi_drv->ops.suspend(acpi_dev, state);
 311         return 0;
 312 }
 313
 314 static int acpi_device_resume(struct device *dev)
 315 {
 316         struct acpi_device *acpi_dev = to_acpi_device(dev);
 317         struct acpi_driver *acpi_drv = acpi_dev->driver;
 318
 319         if (acpi_drv && acpi_drv->ops.resume)
 320                 return acpi_drv->ops.resume(acpi_dev);
 321         return 0;
 322 }
 323
 324 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 325 {
 326         struct acpi_device *acpi_dev = to_acpi_device(dev);
 327         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 328
 329         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 330 }
 331
 332 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 333 {
 334         struct acpi_device *acpi_dev = to_acpi_device(dev);
 335         int len;
 336
 337         if (add_uevent_var(env, "MODALIAS="))
 338                 return -ENOMEM;
 339         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 340                               sizeof(env->buf) - env->buflen);
 341         if (len >= (sizeof(env->buf) - env->buflen))
 342                 return -ENOMEM;
 343         env->buflen += len;
 344         return 0;
 345 }
 346
 347 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 348 {
 349         struct acpi_device *device = data;
 350
 351         device->driver->ops.notify(device, event);
 352 }
 353
 354 static acpi_status acpi_device_notify_fixed(void *data)
 355 {
 356         struct acpi_device *device = data;
 357
 358         /* Fixed hardware devices have no handles */
 359         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 360         return AE_OK;
 361 }
 362
 363 static int acpi_device_install_notify_handler(struct acpi_device *device)
 364 {
 365         acpi_status status;
 366
 367         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 368                 status =
 369                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 370                                                      acpi_device_notify_fixed,
 371                                                      device);
 372         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 373                 status =
 374                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 375                                                      acpi_device_notify_fixed,
 376                                                      device);
 377         else
 378                 status = acpi_install_notify_handler(device->handle,
 379                                                      ACPI_DEVICE_NOTIFY,
 380                                                      acpi_device_notify,
 381                                                      device);
 382
 383         if (ACPI_FAILURE(status))
 384                 return -EINVAL;
 385         return 0;
 386 }
 387
 388 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 389 {
 390         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 391                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 392                                                 acpi_device_notify_fixed);
 393         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 394                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 395                                                 acpi_device_notify_fixed);
 396         else
 397                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 398                                            acpi_device_notify);
 399 }
 400
 401 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
 402 static int acpi_start_single_object(struct acpi_device *);
 403 static int acpi_device_probe(struct device * dev)
 404 {
 405         struct acpi_device *acpi_dev = to_acpi_device(dev);
 406         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 407         int ret;
 408
 409         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
 410         if (!ret) {
 411                 if (acpi_dev->bus_ops.acpi_op_start)
 412                         acpi_start_single_object(acpi_dev);
 413
 414                 if (acpi_drv->ops.notify) {
 415                         ret = acpi_device_install_notify_handler(acpi_dev);
 416                         if (ret) {
 417                                 if (acpi_drv->ops.remove)
 418                                         acpi_drv->ops.remove(acpi_dev,
 419                                                      acpi_dev->removal_type);
 420                                 return ret;
 421                         }
 422                 }
 423
 424                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 425                         "Found driver [%s] for device [%s]\n",
 426                         acpi_drv->name, acpi_dev->pnp.bus_id));
 427                 get_device(dev);
 428         }
 429         return ret;
 430 }
 431
 432 static int acpi_device_remove(struct device * dev)
 433 {
 434         struct acpi_device *acpi_dev = to_acpi_device(dev);
 435         struct acpi_driver *acpi_drv = acpi_dev->driver;
 436
 437         if (acpi_drv) {
 438                 if (acpi_drv->ops.notify)
 439                         acpi_device_remove_notify_handler(acpi_dev);
 440                 if (acpi_drv->ops.remove)
 441                         acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
 442         }
 443         acpi_dev->driver = NULL;
 444         acpi_dev->driver_data = NULL;
 445
 446         put_device(dev);
 447         return 0;
 448 }
 449
 450 struct bus_type acpi_bus_type = {
 451         .name           = "acpi",
 452         .suspend        = acpi_device_suspend,
 453         .resume         = acpi_device_resume,
 454         .match          = acpi_bus_match,
 455         .probe          = acpi_device_probe,
 456         .remove         = acpi_device_remove,
 457         .uevent         = acpi_device_uevent,
 458 };
 459
 460 static int acpi_device_register(struct acpi_device *device)
 461 {
 462         int result;
 463         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 464         int found = 0;
 465
 466         /*
 467          * Linkage
 468          * -------
 469          * Link this device to its parent and siblings.
 470          */
 471         INIT_LIST_HEAD(&device->children);
 472         INIT_LIST_HEAD(&device->node);
 473         INIT_LIST_HEAD(&device->wakeup_list);
 474
 475         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 476         if (!new_bus_id) {
 477                 printk(KERN_ERR PREFIX "Memory allocation error\n");
 478                 return -ENOMEM;
 479         }
 480
 481         mutex_lock(&acpi_device_lock);
 482         /*
 483          * Find suitable bus_id and instance number in acpi_bus_id_list
 484          * If failed, create one and link it into acpi_bus_id_list
 485          */
 486         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 487                 if (!strcmp(acpi_device_bus_id->bus_id,
 488                             acpi_device_hid(device))) {
 489                         acpi_device_bus_id->instance_no++;
 490                         found = 1;
 491                         kfree(new_bus_id);
 492                         break;
 493                 }
 494         }
 495         if (!found) {
 496                 acpi_device_bus_id = new_bus_id;
 497                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
 498                 acpi_device_bus_id->instance_no = 0;
 499                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 500         }
 501         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 502
 503         if (device->parent)
 504                 list_add_tail(&device->node, &device->parent->children);
 505
 506         if (device->wakeup.flags.valid)
 507                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 508         mutex_unlock(&acpi_device_lock);
 509
 510         if (device->parent)
 511                 device->dev.parent = &device->parent->dev;
 512         device->dev.bus = &acpi_bus_type;
 513         device->dev.release = &acpi_device_release;
 514         result = device_register(&device->dev);
 515         if (result) {
 516                 dev_err(&device->dev, "Error registering device\n");
 517                 goto end;
 518         }
 519
 520         result = acpi_device_setup_files(device);
 521         if (result)
 522                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 523                        dev_name(&device->dev));
 524
 525         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
 526         return 0;
 527 end:
 528         mutex_lock(&acpi_device_lock);
 529         if (device->parent)
 530                 list_del(&device->node);
 531         list_del(&device->wakeup_list);
 532         mutex_unlock(&acpi_device_lock);
 533         return result;
 534 }
 535
 536 static void acpi_device_unregister(struct acpi_device *device, int type)
 537 {
 538         mutex_lock(&acpi_device_lock);
 539         if (device->parent)
 540                 list_del(&device->node);
 541
 542         list_del(&device->wakeup_list);
 543         mutex_unlock(&acpi_device_lock);
 544
 545         acpi_detach_data(device->handle, acpi_bus_data_handler);
 546
 547         acpi_device_remove_files(device);
 548         device_unregister(&device->dev);
 549 }
 550
 551 /* --------------------------------------------------------------------------
 552                                  Driver Management
 553    -------------------------------------------------------------------------- */
 554 /**
 555  * acpi_bus_driver_init - add a device to a driver
 556  * @device: the device to add and initialize
 557  * @driver: driver for the device
 558  *
 559  * Used to initialize a device via its device driver.  Called whenever a
 560  * driver is bound to a device.  Invokes the driver's add() ops.
 561  */
 562 static int
 563 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
 564 {
 565         int result = 0;
 566
 567         if (!device || !driver)
 568                 return -EINVAL;
 569
 570         if (!driver->ops.add)
 571                 return -ENOSYS;
 572
 573         result = driver->ops.add(device);
 574         if (result) {
 575                 device->driver = NULL;
 576                 device->driver_data = NULL;
 577                 return result;
 578         }
 579
 580         device->driver = driver;
 581
 582         /*
 583          * TBD - Configuration Management: Assign resources to device based
 584          * upon possible configuration and currently allocated resources.
 585          */
 586
 587         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 588                           "Driver successfully bound to device\n"));
 589         return 0;
 590 }
 591
 592 static int acpi_start_single_object(struct acpi_device *device)
 593 {
 594         int result = 0;
 595         struct acpi_driver *driver;
 596
 597
 598         if (!(driver = device->driver))
 599                 return 0;
 600
 601         if (driver->ops.start) {
 602                 result = driver->ops.start(device);
 603                 if (result && driver->ops.remove)
 604                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
 605         }
 606
 607         return result;
 608 }
 609
 610 /**
 611  * acpi_bus_register_driver - register a driver with the ACPI bus
 612  * @driver: driver being registered
 613  *
 614  * Registers a driver with the ACPI bus.  Searches the namespace for all
 615  * devices that match the driver's criteria and binds.  Returns zero for
 616  * success or a negative error status for failure.
 617  */
 618 int acpi_bus_register_driver(struct acpi_driver *driver)
 619 {
 620         int ret;
 621
 622         if (acpi_disabled)
 623                 return -ENODEV;
 624         driver->drv.name = driver->name;
 625         driver->drv.bus = &acpi_bus_type;
 626         driver->drv.owner = driver->owner;
 627
 628         ret = driver_register(&driver->drv);
 629         return ret;
 630 }
 631
 632 EXPORT_SYMBOL(acpi_bus_register_driver);
 633
 634 /**
 635  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
 636  * @driver: driver to unregister
 637  *
 638  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
 639  * devices that match the driver's criteria and unbinds.
 640  */
 641 void acpi_bus_unregister_driver(struct acpi_driver *driver)
 642 {
 643         driver_unregister(&driver->drv);
 644 }
 645
 646 EXPORT_SYMBOL(acpi_bus_unregister_driver);
 647
 648 /* --------------------------------------------------------------------------
 649                                  Device Enumeration
 650    -------------------------------------------------------------------------- */
 651 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
 652 {
 653         acpi_status status;
 654         int ret;
 655         struct acpi_device *device;
 656
 657         /*
 658          * Fixed hardware devices do not appear in the namespace and do not
 659          * have handles, but we fabricate acpi_devices for them, so we have
 660          * to deal with them specially.
 661          */
 662         if (handle == NULL)
 663                 return acpi_root;
 664
 665         do {
 666                 status = acpi_get_parent(handle, &handle);
 667                 if (status == AE_NULL_ENTRY)
 668                         return NULL;
 669                 if (ACPI_FAILURE(status))
 670                         return acpi_root;
 671
 672                 ret = acpi_bus_get_device(handle, &device);
 673                 if (ret == 0)
 674                         return device;
 675         } while (1);
 676 }
 677
 678 acpi_status
 679 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 680 {
 681         acpi_status status;
 682         acpi_handle tmp;
 683         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 684         union acpi_object *obj;
 685
 686         status = acpi_get_handle(handle, "_EJD", &tmp);
 687         if (ACPI_FAILURE(status))
 688                 return status;
 689
 690         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 691         if (ACPI_SUCCESS(status)) {
 692                 obj = buffer.pointer;
 693                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 694                                          ejd);
 695                 kfree(buffer.pointer);
 696         }
 697         return status;
 698 }
 699 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 700
 701 void acpi_bus_data_handler(acpi_handle handle, void *context)
 702 {
 703
 704         /* TBD */
 705
 706         return;
 707 }
 708
 709 static int acpi_bus_get_perf_flags(struct acpi_device *device)
 710 {
 711         device->performance.state = ACPI_STATE_UNKNOWN;
 712         return 0;
 713 }
 714
 715 static acpi_status
 716 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
 717                                              union acpi_object *package)
 718 {
 719         int i = 0;
 720         union acpi_object *element = NULL;
 721
 722         if (!device || !package || (package->package.count < 2))
 723                 return AE_BAD_PARAMETER;
 724
 725         element = &(package->package.elements[0]);
 726         if (!element)
 727                 return AE_BAD_PARAMETER;
 728         if (element->type == ACPI_TYPE_PACKAGE) {
 729                 if ((element->package.count < 2) ||
 730                     (element->package.elements[0].type !=
 731                      ACPI_TYPE_LOCAL_REFERENCE)
 732                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 733                         return AE_BAD_DATA;
 734                 device->wakeup.gpe_device =
 735                     element->package.elements[0].reference.handle;
 736                 device->wakeup.gpe_number =
 737                     (u32) element->package.elements[1].integer.value;
 738         } else if (element->type == ACPI_TYPE_INTEGER) {
 739                 device->wakeup.gpe_number = element->integer.value;
 740         } else
 741                 return AE_BAD_DATA;
 742
 743         element = &(package->package.elements[1]);
 744         if (element->type != ACPI_TYPE_INTEGER) {
 745                 return AE_BAD_DATA;
 746         }
 747         device->wakeup.sleep_state = element->integer.value;
 748
 749         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
 750                 return AE_NO_MEMORY;
 751         }
 752         device->wakeup.resources.count = package->package.count - 2;
 753         for (i = 0; i < device->wakeup.resources.count; i++) {
 754                 element = &(package->package.elements[i + 2]);
 755                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
 756                         return AE_BAD_DATA;
 757
 758                 device->wakeup.resources.handles[i] = element->reference.handle;
 759         }
 760
 761         return AE_OK;
 762 }
 763
 764 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 765 {
 766         acpi_status status = 0;
 767         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 768         union acpi_object *package = NULL;
 769         int psw_error;
 770
 771         struct acpi_device_id button_device_ids[] = {
 772                 {"PNP0C0D", 0},
 773                 {"PNP0C0C", 0},
 774                 {"PNP0C0E", 0},
 775                 {"", 0},
 776         };
 777
 778         /* _PRW */
 779         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
 780         if (ACPI_FAILURE(status)) {
 781                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 782                 goto end;
 783         }
 784
 785         package = (union acpi_object *)buffer.pointer;
 786         status = acpi_bus_extract_wakeup_device_power_package(device, package);
 787         if (ACPI_FAILURE(status)) {
 788                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
 789                 goto end;
 790         }
 791
 792         kfree(buffer.pointer);
 793
 794         device->wakeup.flags.valid = 1;
 795         device->wakeup.prepare_count = 0;
 796         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
 797          * system for the ACPI device with the _PRW object.
 798          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 799          * So it is necessary to call _DSW object first. Only when it is not
 800          * present will the _PSW object used.
 801          */
 802         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
 803         if (psw_error)
 804                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 805                                 "error in _DSW or _PSW evaluation\n"));
 806
 807         /* Power button, Lid switch always enable wakeup */
 808         if (!acpi_match_device_ids(device, button_device_ids))
 809                 device->wakeup.flags.run_wake = 1;
 810
 811 end:
 812         if (ACPI_FAILURE(status))
 813                 device->flags.wake_capable = 0;
 814         return 0;
 815 }
 816
 817 static int acpi_bus_get_power_flags(struct acpi_device *device)
 818 {
 819         acpi_status status = 0;
 820         acpi_handle handle = NULL;
 821         u32 i = 0;
 822
 823
 824         /*
 825          * Power Management Flags
 826          */
 827         status = acpi_get_handle(device->handle, "_PSC", &handle);
 828         if (ACPI_SUCCESS(status))
 829                 device->power.flags.explicit_get = 1;
 830         status = acpi_get_handle(device->handle, "_IRC", &handle);
 831         if (ACPI_SUCCESS(status))
 832                 device->power.flags.inrush_current = 1;
 833
 834         /*
 835          * Enumerate supported power management states
 836          */
 837         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
 838                 struct acpi_device_power_state *ps = &device->power.states[i];
 839                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
 840
 841                 /* Evaluate "_PRx" to se if power resources are referenced */
 842                 acpi_evaluate_reference(device->handle, object_name, NULL,
 843                                         &ps->resources);
 844                 if (ps->resources.count) {
 845                         device->power.flags.power_resources = 1;
 846                         ps->flags.valid = 1;
 847                 }
 848
 849                 /* Evaluate "_PSx" to see if we can do explicit sets */
 850                 object_name[2] = 'S';
 851                 status = acpi_get_handle(device->handle, object_name, &handle);
 852                 if (ACPI_SUCCESS(status)) {
 853                         ps->flags.explicit_set = 1;
 854                         ps->flags.valid = 1;
 855                 }
 856
 857                 /* State is valid if we have some power control */
 858                 if (ps->resources.count || ps->flags.explicit_set)
 859                         ps->flags.valid = 1;
 860
 861                 ps->power = -1; /* Unknown - driver assigned */
 862                 ps->latency = -1;       /* Unknown - driver assigned */
 863         }
 864
 865         /* Set defaults for D0 and D3 states (always valid) */
 866         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 867         device->power.states[ACPI_STATE_D0].power = 100;
 868         device->power.states[ACPI_STATE_D3].flags.valid = 1;
 869         device->power.states[ACPI_STATE_D3].power = 0;
 870
 871         /* TBD: System wake support and resource requirements. */
 872
 873         device->power.state = ACPI_STATE_UNKNOWN;
 874         acpi_bus_get_power(device->handle, &(device->power.state));
 875
 876         return 0;
 877 }
 878
 879 static int acpi_bus_get_flags(struct acpi_device *device)
 880 {
 881         acpi_status status = AE_OK;
 882         acpi_handle temp = NULL;
 883
 884
 885         /* Presence of _STA indicates 'dynamic_status' */
 886         status = acpi_get_handle(device->handle, "_STA", &temp);
 887         if (ACPI_SUCCESS(status))
 888                 device->flags.dynamic_status = 1;
 889
 890         /* Presence of _RMV indicates 'removable' */
 891         status = acpi_get_handle(device->handle, "_RMV", &temp);
 892         if (ACPI_SUCCESS(status))
 893                 device->flags.removable = 1;
 894
 895         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 896         status = acpi_get_handle(device->handle, "_EJD", &temp);
 897         if (ACPI_SUCCESS(status))
 898                 device->flags.ejectable = 1;
 899         else {
 900                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
 901                 if (ACPI_SUCCESS(status))
 902                         device->flags.ejectable = 1;
 903         }
 904
 905         /* Presence of _LCK indicates 'lockable' */
 906         status = acpi_get_handle(device->handle, "_LCK", &temp);
 907         if (ACPI_SUCCESS(status))
 908                 device->flags.lockable = 1;
 909
 910         /* Presence of _PS0|_PR0 indicates 'power manageable' */
 911         status = acpi_get_handle(device->handle, "_PS0", &temp);
 912         if (ACPI_FAILURE(status))
 913                 status = acpi_get_handle(device->handle, "_PR0", &temp);
 914         if (ACPI_SUCCESS(status))
 915                 device->flags.power_manageable = 1;
 916
 917         /* Presence of _PRW indicates wake capable */
 918         status = acpi_get_handle(device->handle, "_PRW", &temp);
 919         if (ACPI_SUCCESS(status))
 920                 device->flags.wake_capable = 1;
 921
 922         /* TBD: Performance management */
 923
 924         return 0;
 925 }
 926
 927 static void acpi_device_get_busid(struct acpi_device *device)
 928 {
 929         char bus_id[5] = { '?', 0 };
 930         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
 931         int i = 0;
 932
 933         /*
 934          * Bus ID
 935          * ------
 936          * The device's Bus ID is simply the object name.
 937          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
 938          */
 939         if (ACPI_IS_ROOT_DEVICE(device)) {
 940                 strcpy(device->pnp.bus_id, "ACPI");
 941                 return;
 942         }
 943
 944         switch (device->device_type) {
 945         case ACPI_BUS_TYPE_POWER_BUTTON:
 946                 strcpy(device->pnp.bus_id, "PWRF");
 947                 break;
 948         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 949                 strcpy(device->pnp.bus_id, "SLPF");
 950                 break;
 951         default:
 952                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
 953                 /* Clean up trailing underscores (if any) */
 954                 for (i = 3; i > 1; i--) {
 955                         if (bus_id[i] == '_')
 956                                 bus_id[i] = '\0';
 957                         else
 958                                 break;
 959                 }
 960                 strcpy(device->pnp.bus_id, bus_id);
 961                 break;
 962         }
 963 }
 964
 965 /*
 966  * acpi_bay_match - see if a device is an ejectable driver bay
 967  *
 968  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
 969  * then we can safely call it an ejectable drive bay
 970  */
 971 static int acpi_bay_match(struct acpi_device *device){
 972         acpi_status status;
 973         acpi_handle handle;
 974         acpi_handle tmp;
 975         acpi_handle phandle;
 976
 977         handle = device->handle;
 978
 979         status = acpi_get_handle(handle, "_EJ0", &tmp);
 980         if (ACPI_FAILURE(status))
 981                 return -ENODEV;
 982
 983         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
 984                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
 985                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
 986                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
 987                 return 0;
 988
 989         if (acpi_get_parent(handle, &phandle))
 990                 return -ENODEV;
 991
 992         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
 993                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
 994                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
 995                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
 996                 return 0;
 997
 998         return -ENODEV;
 999 }
1000
1001 /*
1002  * acpi_dock_match - see if a device has a _DCK method
1003  */
1004 static int acpi_dock_match(struct acpi_device *device)
1005 {
1006         acpi_handle tmp;
1007         return acpi_get_handle(device->handle, "_DCK", &tmp);
1008 }
1009
1010 char *acpi_device_hid(struct acpi_device *device)
1011 {
1012         struct acpi_hardware_id *hid;
1013
1014         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1015         return hid->id;
1016 }
1017 EXPORT_SYMBOL(acpi_device_hid);
1018
1019 static void acpi_add_id(struct acpi_device *device, const char *dev_id)
1020 {
1021         struct acpi_hardware_id *id;
1022
1023         id = kmalloc(sizeof(*id), GFP_KERNEL);
1024         if (!id)
1025                 return;
1026
1027         id->id = kmalloc(strlen(dev_id) + 1, GFP_KERNEL);
1028         if (!id->id) {
1029                 kfree(id);
1030                 return;
1031         }
1032
1033         strcpy(id->id, dev_id);
1034         list_add_tail(&id->list, &device->pnp.ids);
1035 }
1036
1037 static void acpi_device_set_id(struct acpi_device *device)
1038 {
1039         acpi_status status;
1040         struct acpi_device_info *info;
1041         struct acpica_device_id_list *cid_list;
1042         int i;
1043
1044         switch (device->device_type) {
1045         case ACPI_BUS_TYPE_DEVICE:
1046                 if (ACPI_IS_ROOT_DEVICE(device)) {
1047                         acpi_add_id(device, ACPI_SYSTEM_HID);
1048                         break;
1049                 } else if (ACPI_IS_ROOT_DEVICE(device->parent)) {
1050                         /* \_SB_, the only root-level namespace device */
1051                         acpi_add_id(device, ACPI_BUS_HID);
1052                         strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1053                         strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1054                         break;
1055                 }
1056
1057                 status = acpi_get_object_info(device->handle, &info);
1058                 if (ACPI_FAILURE(status)) {
1059                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1060                         return;
1061                 }
1062
1063                 if (info->valid & ACPI_VALID_HID)
1064                         acpi_add_id(device, info->hardware_id.string);
1065                 if (info->valid & ACPI_VALID_CID) {
1066                         cid_list = &info->compatible_id_list;
1067                         for (i = 0; i < cid_list->count; i++)
1068                                 acpi_add_id(device, cid_list->ids[i].string);
1069                 }
1070 #ifdef CONFIG_PCI_GUESTDEV
1071                 if (info->valid & ACPI_VALID_UID)
1072                         device->pnp.unique_id = kstrdup(info->unique_id.string,
1073                                                         GFP_KERNEL);
1074 #endif
1075                 if (info->valid & ACPI_VALID_ADR) {
1076                         device->pnp.bus_address = info->address;
1077                         device->flags.bus_address = 1;
1078                 }
1079
1080                 kfree(info);
1081
1082                 /*
1083                  * Some devices don't reliably have _HIDs & _CIDs, so add
1084                  * synthetic HIDs to make sure drivers can find them.
1085                  */
1086                 if (acpi_is_video_device(device))
1087                         acpi_add_id(device, ACPI_VIDEO_HID);
1088                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1089                         acpi_add_id(device, ACPI_BAY_HID);
1090                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1091                         acpi_add_id(device, ACPI_DOCK_HID);
1092
1093                 break;
1094         case ACPI_BUS_TYPE_POWER:
1095                 acpi_add_id(device, ACPI_POWER_HID);
1096                 break;
1097         case ACPI_BUS_TYPE_PROCESSOR:
1098                 acpi_add_id(device, ACPI_PROCESSOR_OBJECT_HID);
1099                 break;
1100         case ACPI_BUS_TYPE_THERMAL:
1101                 acpi_add_id(device, ACPI_THERMAL_HID);
1102                 break;
1103         case ACPI_BUS_TYPE_POWER_BUTTON:
1104                 acpi_add_id(device, ACPI_BUTTON_HID_POWERF);
1105                 break;
1106         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1107                 acpi_add_id(device, ACPI_BUTTON_HID_SLEEPF);
1108                 break;
1109         }
1110
1111         /*
1112          * We build acpi_devices for some objects that don't have _HID or _CID,
1113          * e.g., PCI bridges and slots.  Drivers can't bind to these objects,
1114          * but we do use them indirectly by traversing the acpi_device tree.
1115          * This generic ID isn't useful for driver binding, but it provides
1116          * the useful property that "every acpi_device has an ID."
1117          */
1118         if (list_empty(&device->pnp.ids))
1119                 acpi_add_id(device, "device");
1120 }
1121
1122 static int acpi_device_set_context(struct acpi_device *device)
1123 {
1124         acpi_status status;
1125
1126         /*
1127          * Context
1128          * -------
1129          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1130          * resolutions from handle->device very efficient.  Fixed hardware
1131          * devices have no handles, so we skip them.
1132          */
1133         if (!device->handle)
1134                 return 0;
1135
1136         status = acpi_attach_data(device->handle,
1137                                   acpi_bus_data_handler, device);
1138         if (ACPI_SUCCESS(status))
1139                 return 0;
1140
1141         printk(KERN_ERR PREFIX "Error attaching device data\n");
1142         return -ENODEV;
1143 }
1144
1145 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1146 {
1147         if (!dev)
1148                 return -EINVAL;
1149
1150         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1151         device_release_driver(&dev->dev);
1152
1153         if (!rmdevice)
1154                 return 0;
1155
1156         /*
1157          * unbind _ADR-Based Devices when hot removal
1158          */
1159         if (dev->flags.bus_address) {
1160                 if ((dev->parent) && (dev->parent->ops.unbind))
1161                         dev->parent->ops.unbind(dev);
1162         }
1163         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1164
1165         return 0;
1166 }
1167
1168 static int acpi_add_single_object(struct acpi_device **child,
1169                                   acpi_handle handle, int type,
1170                                   unsigned long long sta,
1171                                   struct acpi_bus_ops *ops)
1172 {
1173         int result;
1174         struct acpi_device *device;
1175         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1176
1177         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1178         if (!device) {
1179                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1180                 return -ENOMEM;
1181         }
1182
1183         INIT_LIST_HEAD(&device->pnp.ids);
1184         device->device_type = type;
1185         device->handle = handle;
1186         device->parent = acpi_bus_get_parent(handle);
1187         device->bus_ops = *ops; /* workround for not call .start */
1188         STRUCT_TO_INT(device->status) = sta;
1189
1190         acpi_device_get_busid(device);
1191
1192         /*
1193          * Flags
1194          * -----
1195          * Note that we only look for object handles -- cannot evaluate objects
1196          * until we know the device is present and properly initialized.
1197          */
1198         result = acpi_bus_get_flags(device);
1199         if (result)
1200                 goto end;
1201
1202         /*
1203          * Initialize Device
1204          * -----------------
1205          * TBD: Synch with Core's enumeration/initialization process.
1206          */
1207         acpi_device_set_id(device);
1208
1209         /*
1210          * Power Management
1211          * ----------------
1212          */
1213         if (device->flags.power_manageable) {
1214                 result = acpi_bus_get_power_flags(device);
1215                 if (result)
1216                         goto end;
1217         }
1218
1219         /*
1220          * Wakeup device management
1221          *-----------------------
1222          */
1223         if (device->flags.wake_capable) {
1224                 result = acpi_bus_get_wakeup_device_flags(device);
1225                 if (result)
1226                         goto end;
1227         }
1228
1229         /*
1230          * Performance Management
1231          * ----------------------
1232          */
1233         if (device->flags.performance_manageable) {
1234                 result = acpi_bus_get_perf_flags(device);
1235                 if (result)
1236                         goto end;
1237         }
1238
1239         if ((result = acpi_device_set_context(device)))
1240                 goto end;
1241
1242         result = acpi_device_register(device);
1243
1244         /*
1245          * Bind _ADR-Based Devices when hot add
1246          */
1247         if (device->flags.bus_address) {
1248                 if (device->parent && device->parent->ops.bind)
1249                         device->parent->ops.bind(device);
1250         }
1251
1252 end:
1253         if (!result) {
1254                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1255                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1256                         "Adding %s [%s] parent %s\n", dev_name(&device->dev),
1257                          (char *) buffer.pointer,
1258                          device->parent ? dev_name(&device->parent->dev) :
1259                                           "(null)"));
1260                 kfree(buffer.pointer);
1261                 *child = device;
1262         } else
1263                 acpi_device_release(&device->dev);
1264
1265         return result;
1266 }
1267
1268 #define ACPI_STA_DEFAULT (ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED | \
1269                           ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING)
1270
1271 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1272                                     unsigned long long *sta)
1273 {
1274         acpi_status status;
1275         acpi_object_type acpi_type;
1276
1277         status = acpi_get_type(handle, &acpi_type);
1278         if (ACPI_FAILURE(status))
1279                 return -ENODEV;
1280
1281         switch (acpi_type) {
1282         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1283         case ACPI_TYPE_DEVICE:
1284                 *type = ACPI_BUS_TYPE_DEVICE;
1285                 status = acpi_bus_get_status_handle(handle, sta);
1286                 if (ACPI_FAILURE(status))
1287                         return -ENODEV;
1288                 break;
1289         case ACPI_TYPE_PROCESSOR:
1290                 *type = ACPI_BUS_TYPE_PROCESSOR;
1291                 status = acpi_bus_get_status_handle(handle, sta);
1292                 if (ACPI_FAILURE(status))
1293                         return -ENODEV;
1294                 break;
1295         case ACPI_TYPE_THERMAL:
1296                 *type = ACPI_BUS_TYPE_THERMAL;
1297                 *sta = ACPI_STA_DEFAULT;
1298                 break;
1299         case ACPI_TYPE_POWER:
1300                 *type = ACPI_BUS_TYPE_POWER;
1301                 *sta = ACPI_STA_DEFAULT;
1302                 break;
1303         default:
1304                 return -ENODEV;
1305         }
1306
1307         return 0;
1308 }
1309
1310 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl,
1311                                       void *context, void **return_value)
1312 {
1313         struct acpi_bus_ops *ops = context;
1314         int type;
1315         unsigned long long sta;
1316         struct acpi_device *device;
1317         acpi_status status;
1318         int result;
1319
1320         result = acpi_bus_type_and_status(handle, &type, &sta);
1321         if (result)
1322                 return AE_OK;
1323
1324         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1325             !(sta & ACPI_STA_DEVICE_FUNCTIONING))
1326                 return AE_CTRL_DEPTH;
1327
1328         /*
1329          * We may already have an acpi_device from a previous enumeration.  If
1330          * so, we needn't add it again, but we may still have to start it.
1331          */
1332         device = NULL;
1333         acpi_bus_get_device(handle, &device);
1334         if (ops->acpi_op_add && !device)
1335                 acpi_add_single_object(&device, handle, type, sta, ops);
1336
1337         if (!device)
1338                 return AE_CTRL_DEPTH;
1339
1340         if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1341                 status = acpi_start_single_object(device);
1342                 if (ACPI_FAILURE(status))
1343                         return AE_CTRL_DEPTH;
1344         }
1345
1346         if (!*return_value)
1347                 *return_value = device;
1348         return AE_OK;
1349 }
1350
1351 static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops,
1352                          struct acpi_device **child)
1353 {
1354         acpi_status status;
1355         void *device = NULL;
1356
1357         status = acpi_bus_check_add(handle, 0, ops, &device);
1358         if (ACPI_SUCCESS(status))
1359                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1360                                     acpi_bus_check_add, NULL, ops, &device);
1361
1362         if (child)
1363                 *child = device;
1364         return 0;
1365 }
1366
1367 int
1368 acpi_bus_add(struct acpi_device **child,
1369              struct acpi_device *parent, acpi_handle handle, int type)
1370 {
1371         struct acpi_bus_ops ops;
1372
1373         memset(&ops, 0, sizeof(ops));
1374         ops.acpi_op_add = 1;
1375
1376         acpi_bus_scan(handle, &ops, child);
1377         return 0;
1378 }
1379 EXPORT_SYMBOL(acpi_bus_add);
1380
1381 int acpi_bus_start(struct acpi_device *device)
1382 {
1383         struct acpi_bus_ops ops;
1384
1385         memset(&ops, 0, sizeof(ops));
1386         ops.acpi_op_start = 1;
1387
1388         acpi_bus_scan(device->handle, &ops, NULL);
1389         return 0;
1390 }
1391 EXPORT_SYMBOL(acpi_bus_start);
1392
1393 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1394 {
1395         acpi_status status;
1396         struct acpi_device *parent, *child;
1397         acpi_handle phandle, chandle;
1398         acpi_object_type type;
1399         u32 level = 1;
1400         int err = 0;
1401
1402         parent = start;
1403         phandle = start->handle;
1404         child = chandle = NULL;
1405
1406         while ((level > 0) && parent && (!err)) {
1407                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1408                                               chandle, &chandle);
1409
1410                 /*
1411                  * If this scope is exhausted then move our way back up.
1412                  */
1413                 if (ACPI_FAILURE(status)) {
1414                         level--;
1415                         chandle = phandle;
1416                         acpi_get_parent(phandle, &phandle);
1417                         child = parent;
1418                         parent = parent->parent;
1419
1420                         if (level == 0)
1421                                 err = acpi_bus_remove(child, rmdevice);
1422                         else
1423                                 err = acpi_bus_remove(child, 1);
1424
1425                         continue;
1426                 }
1427
1428                 status = acpi_get_type(chandle, &type);
1429                 if (ACPI_FAILURE(status)) {
1430                         continue;
1431                 }
1432                 /*
1433                  * If there is a device corresponding to chandle then
1434                  * parse it (depth-first).
1435                  */
1436                 if (acpi_bus_get_device(chandle, &child) == 0) {
1437                         level++;
1438                         phandle = chandle;
1439                         chandle = NULL;
1440                         parent = child;
1441                 }
1442                 continue;
1443         }
1444         return err;
1445 }
1446 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1447
1448 static int acpi_bus_scan_fixed(void)
1449 {
1450         int result = 0;
1451         struct acpi_device *device = NULL;
1452         struct acpi_bus_ops ops;
1453
1454         memset(&ops, 0, sizeof(ops));
1455         ops.acpi_op_add = 1;
1456         ops.acpi_op_start = 1;
1457
1458         /*
1459          * Enumerate all fixed-feature devices.
1460          */
1461         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1462                 result = acpi_add_single_object(&device, NULL,
1463                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1464                                                 ACPI_STA_DEFAULT,
1465                                                 &ops);
1466         }
1467
1468         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1469                 result = acpi_add_single_object(&device, NULL,
1470                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1471                                                 ACPI_STA_DEFAULT,
1472                                                 &ops);
1473         }
1474
1475         return result;
1476 }
1477
1478 int __init acpi_scan_init(void)
1479 {
1480         int result;
1481         struct acpi_bus_ops ops;
1482
1483         memset(&ops, 0, sizeof(ops));
1484         ops.acpi_op_add = 1;
1485         ops.acpi_op_start = 1;
1486
1487         result = bus_register(&acpi_bus_type);
1488         if (result) {
1489                 /* We don't want to quit even if we failed to add suspend/resume */
1490                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1491         }
1492
1493         /*
1494          * Enumerate devices in the ACPI namespace.
1495          */
1496         result = acpi_bus_scan(ACPI_ROOT_OBJECT, &ops, &acpi_root);
1497
1498         if (!result)
1499                 result = acpi_bus_scan_fixed();
1500
1501         if (result)
1502                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1503
1504         return result;
1505 }