drivers/acpi/scan.c

   1 /*
   2  * scan.c - support for transforming the ACPI namespace into individual objects
   3  */
   4
   5 #include <linux/module.h>
   6 #include <linux/init.h>
   7 #include <linux/slab.h>
   8 #include <linux/kernel.h>
   9 #include <linux/acpi.h>
  10 #include <linux/signal.h>
  11 #include <linux/kthread.h>
  12 #include <linux/dmi.h>
  13
  14 #include <acpi/acpi_drivers.h>
  15
  16 #include "internal.h"
  17
  18 #define _COMPONENT              ACPI_BUS_COMPONENT
  19 ACPI_MODULE_NAME("scan");
  20 #define STRUCT_TO_INT(s)        (*((int*)&s))
  21 extern struct acpi_device *acpi_root;
  22
  23 #define ACPI_BUS_CLASS                  "system_bus"
  24 #define ACPI_BUS_HID                    "LNXSYBUS"
  25 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  26
  27 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
  28
  29 static const char *dummy_hid = "device";
  30
  31 static LIST_HEAD(acpi_device_list);
  32 static LIST_HEAD(acpi_bus_id_list);
  33 DEFINE_MUTEX(acpi_device_lock);
  34 LIST_HEAD(acpi_wakeup_device_list);
  35
  36 struct acpi_device_bus_id{
  37         char bus_id[15];
  38         unsigned int instance_no;
  39         struct list_head node;
  40 };
  41
  42 /*
  43  * Creates hid/cid(s) string needed for modalias and uevent
  44  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
  45  * char *modalias: "acpi:IBM0001:ACPI0001"
  46 */
  47 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
  48                            int size)
  49 {
  50         int len;
  51         int count;
  52         struct acpi_hardware_id *id;
  53
  54         if (list_empty(&acpi_dev->pnp.ids))
  55                 return 0;
  56
  57         len = snprintf(modalias, size, "acpi:");
  58         size -= len;
  59
  60         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
  61                 count = snprintf(&modalias[len], size, "%s:", id->id);
  62                 if (count < 0 || count >= size)
  63                         return -EINVAL;
  64                 len += count;
  65                 size -= count;
  66         }
  67
  68         modalias[len] = '\0';
  69         return len;
  70 }
  71
  72 static ssize_t
  73 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
  74         struct acpi_device *acpi_dev = to_acpi_device(dev);
  75         int len;
  76
  77         /* Device has no HID and no CID or string is >1024 */
  78         len = create_modalias(acpi_dev, buf, 1024);
  79         if (len <= 0)
  80                 return 0;
  81         buf[len++] = '\n';
  82         return len;
  83 }
  84 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
  85
  86 static void acpi_bus_hot_remove_device(void *context)
  87 {
  88         struct acpi_device *device;
  89         acpi_handle handle = context;
  90         struct acpi_object_list arg_list;
  91         union acpi_object arg;
  92         acpi_status status = AE_OK;
  93
  94         if (acpi_bus_get_device(handle, &device))
  95                 return;
  96
  97         if (!device)
  98                 return;
  99
 100         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 101                 "Hot-removing device %s...\n", dev_name(&device->dev)));
 102
 103         if (acpi_bus_trim(device, 1)) {
 104                 printk(KERN_ERR PREFIX
 105                                 "Removing device failed\n");
 106                 return;
 107         }
 108
 109         /* power off device */
 110         status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
 111         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
 112                 printk(KERN_WARNING PREFIX
 113                                 "Power-off device failed\n");
 114
 115         if (device->flags.lockable) {
 116                 arg_list.count = 1;
 117                 arg_list.pointer = &arg;
 118                 arg.type = ACPI_TYPE_INTEGER;
 119                 arg.integer.value = 0;
 120                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
 121         }
 122
 123         arg_list.count = 1;
 124         arg_list.pointer = &arg;
 125         arg.type = ACPI_TYPE_INTEGER;
 126         arg.integer.value = 1;
 127
 128         /*
 129          * TBD: _EJD support.
 130          */
 131         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
 132         if (ACPI_FAILURE(status))
 133                 printk(KERN_WARNING PREFIX
 134                                 "Eject device failed\n");
 135
 136         return;
 137 }
 138
 139 static ssize_t
 140 acpi_eject_store(struct device *d, struct device_attribute *attr,
 141                 const char *buf, size_t count)
 142 {
 143         int ret = count;
 144         acpi_status status;
 145         acpi_object_type type = 0;
 146         struct acpi_device *acpi_device = to_acpi_device(d);
 147
 148         if ((!count) || (buf[0] != '1')) {
 149                 return -EINVAL;
 150         }
 151 #ifndef FORCE_EJECT
 152         if (acpi_device->driver == NULL) {
 153                 ret = -ENODEV;
 154                 goto err;
 155         }
 156 #endif
 157         status = acpi_get_type(acpi_device->handle, &type);
 158         if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
 159                 ret = -ENODEV;
 160                 goto err;
 161         }
 162
 163         acpi_os_hotplug_execute(acpi_bus_hot_remove_device, acpi_device->handle);
 164 err:
 165         return ret;
 166 }
 167
 168 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 169
 170 static ssize_t
 171 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 172         struct acpi_device *acpi_dev = to_acpi_device(dev);
 173
 174         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
 175 }
 176 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 177
 178 #ifdef CONFIG_PCI_GUESTDEV
 179 static ssize_t
 180 acpi_device_uid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 181         struct acpi_device *acpi_dev = to_acpi_device(dev);
 182
 183         return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
 184 }
 185 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
 186 #endif
 187
 188 static ssize_t
 189 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 190         struct acpi_device *acpi_dev = to_acpi_device(dev);
 191         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 192         int result;
 193
 194         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 195         if (result)
 196                 goto end;
 197
 198         result = sprintf(buf, "%s\n", (char*)path.pointer);
 199         kfree(path.pointer);
 200 end:
 201         return result;
 202 }
 203 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 204
 205 static int acpi_device_setup_files(struct acpi_device *dev)
 206 {
 207         acpi_status status;
 208         acpi_handle temp;
 209         int result = 0;
 210
 211         /*
 212          * Devices gotten from FADT don't have a "path" attribute
 213          */
 214         if (dev->handle) {
 215                 result = device_create_file(&dev->dev, &dev_attr_path);
 216                 if (result)
 217                         goto end;
 218         }
 219
 220         if (!list_empty(&dev->pnp.ids)) {
 221                 result = device_create_file(&dev->dev, &dev_attr_hid);
 222                 if (result)
 223                         goto end;
 224
 225                 result = device_create_file(&dev->dev, &dev_attr_modalias);
 226                 if (result)
 227                         goto end;
 228         }
 229
 230 #ifdef CONFIG_PCI_GUESTDEV
 231         if(dev->pnp.unique_id) {
 232                 result = device_create_file(&dev->dev, &dev_attr_uid);
 233                 if(result)
 234                         goto end;
 235         }
 236 #endif
 237         /*
 238          * If device has _EJ0, 'eject' file is created that is used to trigger
 239          * hot-removal function from userland.
 240          */
 241         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 242         if (ACPI_SUCCESS(status))
 243                 result = device_create_file(&dev->dev, &dev_attr_eject);
 244 end:
 245         return result;
 246 }
 247
 248 static void acpi_device_remove_files(struct acpi_device *dev)
 249 {
 250         acpi_status status;
 251         acpi_handle temp;
 252
 253         /*
 254          * If device has _EJ0, 'eject' file is created that is used to trigger
 255          * hot-removal function from userland.
 256          */
 257         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 258         if (ACPI_SUCCESS(status))
 259                 device_remove_file(&dev->dev, &dev_attr_eject);
 260
 261         device_remove_file(&dev->dev, &dev_attr_modalias);
 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         struct acpi_hardware_id *hwid;
 275
 276         /*
 277          * If the device is not present, it is unnecessary to load device
 278          * driver for it.
 279          */
 280         if (!device->status.present)
 281                 return -ENODEV;
 282
 283         for (id = ids; id->id[0]; id++)
 284                 list_for_each_entry(hwid, &device->pnp.ids, list)
 285                         if (!strcmp((char *) id->id, hwid->id))
 286                                 return 0;
 287
 288         return -ENOENT;
 289 }
 290 EXPORT_SYMBOL(acpi_match_device_ids);
 291
 292 static void acpi_free_ids(struct acpi_device *device)
 293 {
 294         struct acpi_hardware_id *id, *tmp;
 295
 296         list_for_each_entry_safe(id, tmp, &device->pnp.ids, list) {
 297                 kfree(id->id);
 298                 kfree(id);
 299         }
 300 #ifdef CONFIG_PCI_GUESTDEV
 301         kfree(device->pnp.unique_id);
 302 #endif
 303 }
 304
 305 static void acpi_device_release(struct device *dev)
 306 {
 307         struct acpi_device *acpi_dev = to_acpi_device(dev);
 308
 309         acpi_free_ids(acpi_dev);
 310         kfree(acpi_dev);
 311 }
 312
 313 static int acpi_device_suspend(struct device *dev, pm_message_t state)
 314 {
 315         struct acpi_device *acpi_dev = to_acpi_device(dev);
 316         struct acpi_driver *acpi_drv = acpi_dev->driver;
 317
 318         if (acpi_drv && acpi_drv->ops.suspend)
 319                 return acpi_drv->ops.suspend(acpi_dev, state);
 320         return 0;
 321 }
 322
 323 static int acpi_device_resume(struct device *dev)
 324 {
 325         struct acpi_device *acpi_dev = to_acpi_device(dev);
 326         struct acpi_driver *acpi_drv = acpi_dev->driver;
 327
 328         if (acpi_drv && acpi_drv->ops.resume)
 329                 return acpi_drv->ops.resume(acpi_dev);
 330         return 0;
 331 }
 332
 333 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 334 {
 335         struct acpi_device *acpi_dev = to_acpi_device(dev);
 336         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 337
 338         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 339 }
 340
 341 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 342 {
 343         struct acpi_device *acpi_dev = to_acpi_device(dev);
 344         int len;
 345
 346         if (list_empty(&acpi_dev->pnp.ids))
 347                 return 0;
 348
 349         if (add_uevent_var(env, "MODALIAS="))
 350                 return -ENOMEM;
 351         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 352                               sizeof(env->buf) - env->buflen);
 353         if (len >= (sizeof(env->buf) - env->buflen))
 354                 return -ENOMEM;
 355         env->buflen += len;
 356         return 0;
 357 }
 358
 359 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 360 {
 361         struct acpi_device *device = data;
 362
 363         device->driver->ops.notify(device, event);
 364 }
 365
 366 static acpi_status acpi_device_notify_fixed(void *data)
 367 {
 368         struct acpi_device *device = data;
 369
 370         /* Fixed hardware devices have no handles */
 371         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 372         return AE_OK;
 373 }
 374
 375 static int acpi_device_install_notify_handler(struct acpi_device *device)
 376 {
 377         acpi_status status;
 378
 379         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 380                 status =
 381                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 382                                                      acpi_device_notify_fixed,
 383                                                      device);
 384         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 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 (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 403                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 404                                                 acpi_device_notify_fixed);
 405         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 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 {
 474         int result;
 475         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 476         int found = 0;
 477
 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,
 500                             acpi_device_hid(device))) {
 501                         acpi_device_bus_id->instance_no++;
 502                         found = 1;
 503                         kfree(new_bus_id);
 504                         break;
 505                 }
 506         }
 507         if (!found) {
 508                 acpi_device_bus_id = new_bus_id;
 509                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
 510                 acpi_device_bus_id->instance_no = 0;
 511                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 512         }
 513         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 514
 515         if (device->parent)
 516                 list_add_tail(&device->node, &device->parent->children);
 517
 518         if (device->wakeup.flags.valid)
 519                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 520         mutex_unlock(&acpi_device_lock);
 521
 522         if (device->parent)
 523                 device->dev.parent = &device->parent->dev;
 524         device->dev.bus = &acpi_bus_type;
 525         device->dev.release = &acpi_device_release;
 526         result = device_register(&device->dev);
 527         if (result) {
 528                 dev_err(&device->dev, "Error registering device\n");
 529                 goto end;
 530         }
 531
 532         result = acpi_device_setup_files(device);
 533         if (result)
 534                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 535                        dev_name(&device->dev));
 536
 537         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
 538         return 0;
 539 end:
 540         mutex_lock(&acpi_device_lock);
 541         if (device->parent)
 542                 list_del(&device->node);
 543         list_del(&device->wakeup_list);
 544         mutex_unlock(&acpi_device_lock);
 545         return result;
 546 }
 547
 548 static void acpi_device_unregister(struct acpi_device *device, int type)
 549 {
 550         mutex_lock(&acpi_device_lock);
 551         if (device->parent)
 552                 list_del(&device->node);
 553
 554         list_del(&device->wakeup_list);
 555         mutex_unlock(&acpi_device_lock);
 556
 557         acpi_detach_data(device->handle, acpi_bus_data_handler);
 558
 559         acpi_device_remove_files(device);
 560         device_unregister(&device->dev);
 561 }
 562
 563 /* --------------------------------------------------------------------------
 564                                  Driver Management
 565    -------------------------------------------------------------------------- */
 566 /**
 567  * acpi_bus_driver_init - add a device to a driver
 568  * @device: the device to add and initialize
 569  * @driver: driver for the device
 570  *
 571  * Used to initialize a device via its device driver.  Called whenever a
 572  * driver is bound to a device.  Invokes the driver's add() ops.
 573  */
 574 static int
 575 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
 576 {
 577         int result = 0;
 578
 579         if (!device || !driver)
 580                 return -EINVAL;
 581
 582         if (!driver->ops.add)
 583                 return -ENOSYS;
 584
 585         result = driver->ops.add(device);
 586         if (result) {
 587                 device->driver = NULL;
 588                 device->driver_data = NULL;
 589                 return result;
 590         }
 591
 592         device->driver = driver;
 593
 594         /*
 595          * TBD - Configuration Management: Assign resources to device based
 596          * upon possible configuration and currently allocated resources.
 597          */
 598
 599         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 600                           "Driver successfully bound to device\n"));
 601         return 0;
 602 }
 603
 604 static int acpi_start_single_object(struct acpi_device *device)
 605 {
 606         int result = 0;
 607         struct acpi_driver *driver;
 608
 609
 610         if (!(driver = device->driver))
 611                 return 0;
 612
 613         if (driver->ops.start) {
 614                 result = driver->ops.start(device);
 615                 if (result && driver->ops.remove)
 616                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
 617         }
 618
 619         return result;
 620 }
 621
 622 /**
 623  * acpi_bus_register_driver - register a driver with the ACPI bus
 624  * @driver: driver being registered
 625  *
 626  * Registers a driver with the ACPI bus.  Searches the namespace for all
 627  * devices that match the driver's criteria and binds.  Returns zero for
 628  * success or a negative error status for failure.
 629  */
 630 int acpi_bus_register_driver(struct acpi_driver *driver)
 631 {
 632         int ret;
 633
 634         if (acpi_disabled)
 635                 return -ENODEV;
 636         driver->drv.name = driver->name;
 637         driver->drv.bus = &acpi_bus_type;
 638         driver->drv.owner = driver->owner;
 639
 640         ret = driver_register(&driver->drv);
 641         return ret;
 642 }
 643
 644 EXPORT_SYMBOL(acpi_bus_register_driver);
 645
 646 /**
 647  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
 648  * @driver: driver to unregister
 649  *
 650  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
 651  * devices that match the driver's criteria and unbinds.
 652  */
 653 void acpi_bus_unregister_driver(struct acpi_driver *driver)
 654 {
 655         driver_unregister(&driver->drv);
 656 }
 657
 658 EXPORT_SYMBOL(acpi_bus_unregister_driver);
 659
 660 /* --------------------------------------------------------------------------
 661                                  Device Enumeration
 662    -------------------------------------------------------------------------- */
 663 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
 664 {
 665         acpi_status status;
 666         int ret;
 667         struct acpi_device *device;
 668
 669         /*
 670          * Fixed hardware devices do not appear in the namespace and do not
 671          * have handles, but we fabricate acpi_devices for them, so we have
 672          * to deal with them specially.
 673          */
 674         if (handle == NULL)
 675                 return acpi_root;
 676
 677         do {
 678                 status = acpi_get_parent(handle, &handle);
 679                 if (status == AE_NULL_ENTRY)
 680                         return NULL;
 681                 if (ACPI_FAILURE(status))
 682                         return acpi_root;
 683
 684                 ret = acpi_bus_get_device(handle, &device);
 685                 if (ret == 0)
 686                         return device;
 687         } while (1);
 688 }
 689
 690 acpi_status
 691 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 692 {
 693         acpi_status status;
 694         acpi_handle tmp;
 695         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 696         union acpi_object *obj;
 697
 698         status = acpi_get_handle(handle, "_EJD", &tmp);
 699         if (ACPI_FAILURE(status))
 700                 return status;
 701
 702         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 703         if (ACPI_SUCCESS(status)) {
 704                 obj = buffer.pointer;
 705                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 706                                          ejd);
 707                 kfree(buffer.pointer);
 708         }
 709         return status;
 710 }
 711 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 712
 713 void acpi_bus_data_handler(acpi_handle handle, void *context)
 714 {
 715
 716         /* TBD */
 717
 718         return;
 719 }
 720
 721 static int acpi_bus_get_perf_flags(struct acpi_device *device)
 722 {
 723         device->performance.state = ACPI_STATE_UNKNOWN;
 724         return 0;
 725 }
 726
 727 static acpi_status
 728 acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
 729                                              struct acpi_device_wakeup *wakeup)
 730 {
 731         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 732         union acpi_object *package = NULL;
 733         union acpi_object *element = NULL;
 734         acpi_status status;
 735         int i = 0;
 736
 737         if (!wakeup)
 738                 return AE_BAD_PARAMETER;
 739
 740         /* _PRW */
 741         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
 742         if (ACPI_FAILURE(status)) {
 743                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 744                 return status;
 745         }
 746
 747         package = (union acpi_object *)buffer.pointer;
 748
 749         if (!package || (package->package.count < 2)) {
 750                 status = AE_BAD_DATA;
 751                 goto out;
 752         }
 753
 754         element = &(package->package.elements[0]);
 755         if (!element) {
 756                 status = AE_BAD_DATA;
 757                 goto out;
 758         }
 759         if (element->type == ACPI_TYPE_PACKAGE) {
 760                 if ((element->package.count < 2) ||
 761                     (element->package.elements[0].type !=
 762                      ACPI_TYPE_LOCAL_REFERENCE)
 763                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER)) {
 764                         status = AE_BAD_DATA;
 765                         goto out;
 766                 }
 767                 wakeup->gpe_device =
 768                     element->package.elements[0].reference.handle;
 769                 wakeup->gpe_number =
 770                     (u32) element->package.elements[1].integer.value;
 771         } else if (element->type == ACPI_TYPE_INTEGER) {
 772                 wakeup->gpe_device = NULL;
 773                 wakeup->gpe_number = element->integer.value;
 774         } else {
 775                 status = AE_BAD_DATA;
 776                 goto out;
 777         }
 778
 779         element = &(package->package.elements[1]);
 780         if (element->type != ACPI_TYPE_INTEGER) {
 781                 status = AE_BAD_DATA;
 782                 goto out;
 783         }
 784         wakeup->sleep_state = element->integer.value;
 785
 786         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
 787                 status = AE_NO_MEMORY;
 788                 goto out;
 789         }
 790         wakeup->resources.count = package->package.count - 2;
 791         for (i = 0; i < wakeup->resources.count; i++) {
 792                 element = &(package->package.elements[i + 2]);
 793                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
 794                         status = AE_BAD_DATA;
 795                         goto out;
 796                 }
 797
 798                 wakeup->resources.handles[i] = element->reference.handle;
 799         }
 800
 801         acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
 802
 803  out:
 804         kfree(buffer.pointer);
 805
 806         return status;
 807 }
 808
 809 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
 810 {
 811         struct acpi_device_id button_device_ids[] = {
 812                 {"PNP0C0D", 0},
 813                 {"PNP0C0C", 0},
 814                 {"PNP0C0E", 0},
 815                 {"", 0},
 816         };
 817         acpi_status status;
 818         acpi_event_status event_status;
 819
 820         device->wakeup.flags.notifier_present = 0;
 821
 822         /* Power button, Lid switch always enable wakeup */
 823         if (!acpi_match_device_ids(device, button_device_ids)) {
 824                 device->wakeup.flags.run_wake = 1;
 825                 device_set_wakeup_capable(&device->dev, true);
 826                 return;
 827         }
 828
 829         status = acpi_get_gpe_status(device->wakeup.gpe_device,
 830                                         device->wakeup.gpe_number,
 831                                                 &event_status);
 832         if (status == AE_OK)
 833                 device->wakeup.flags.run_wake =
 834                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
 835 }
 836
 837 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 838 {
 839         acpi_handle temp;
 840         acpi_status status = 0;
 841         int psw_error;
 842
 843         /* Presence of _PRW indicates wake capable */
 844         status = acpi_get_handle(device->handle, "_PRW", &temp);
 845         if (ACPI_FAILURE(status))
 846                 return;
 847
 848         status = acpi_bus_extract_wakeup_device_power_package(device->handle,
 849                                                               &device->wakeup);
 850         if (ACPI_FAILURE(status)) {
 851                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
 852                 return;
 853         }
 854
 855         device->wakeup.flags.valid = 1;
 856         device->wakeup.prepare_count = 0;
 857         acpi_bus_set_run_wake_flags(device);
 858         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
 859          * system for the ACPI device with the _PRW object.
 860          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 861          * So it is necessary to call _DSW object first. Only when it is not
 862          * present will the _PSW object used.
 863          */
 864         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
 865         if (psw_error)
 866                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 867                                 "error in _DSW or _PSW evaluation\n"));
 868 }
 869
 870 static void acpi_bus_add_power_resource(acpi_handle handle);
 871
 872 static int acpi_bus_get_power_flags(struct acpi_device *device)
 873 {
 874         acpi_status status = 0;
 875         acpi_handle handle = NULL;
 876         u32 i = 0;
 877
 878
 879         /*
 880          * Power Management Flags
 881          */
 882         status = acpi_get_handle(device->handle, "_PSC", &handle);
 883         if (ACPI_SUCCESS(status))
 884                 device->power.flags.explicit_get = 1;
 885         status = acpi_get_handle(device->handle, "_IRC", &handle);
 886         if (ACPI_SUCCESS(status))
 887                 device->power.flags.inrush_current = 1;
 888
 889         /*
 890          * Enumerate supported power management states
 891          */
 892         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
 893                 struct acpi_device_power_state *ps = &device->power.states[i];
 894                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
 895
 896                 /* Evaluate "_PRx" to se if power resources are referenced */
 897                 acpi_evaluate_reference(device->handle, object_name, NULL,
 898                                         &ps->resources);
 899                 if (ps->resources.count) {
 900                         int j;
 901
 902                         device->power.flags.power_resources = 1;
 903                         ps->flags.valid = 1;
 904                         for (j = 0; j < ps->resources.count; j++)
 905                                 acpi_bus_add_power_resource(ps->resources.handles[j]);
 906                 }
 907
 908                 /* Evaluate "_PSx" to see if we can do explicit sets */
 909                 object_name[2] = 'S';
 910                 status = acpi_get_handle(device->handle, object_name, &handle);
 911                 if (ACPI_SUCCESS(status)) {
 912                         ps->flags.explicit_set = 1;
 913                         ps->flags.valid = 1;
 914                 }
 915
 916                 /* State is valid if we have some power control */
 917                 if (ps->resources.count || ps->flags.explicit_set)
 918                         ps->flags.valid = 1;
 919
 920                 ps->power = -1; /* Unknown - driver assigned */
 921                 ps->latency = -1;       /* Unknown - driver assigned */
 922         }
 923
 924         /* Set defaults for D0 and D3 states (always valid) */
 925         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 926         device->power.states[ACPI_STATE_D0].power = 100;
 927         device->power.states[ACPI_STATE_D3].flags.valid = 1;
 928         device->power.states[ACPI_STATE_D3].power = 0;
 929
 930         acpi_bus_init_power(device);
 931
 932         return 0;
 933 }
 934
 935 static int acpi_bus_get_flags(struct acpi_device *device)
 936 {
 937         acpi_status status = AE_OK;
 938         acpi_handle temp = NULL;
 939
 940
 941         /* Presence of _STA indicates 'dynamic_status' */
 942         status = acpi_get_handle(device->handle, "_STA", &temp);
 943         if (ACPI_SUCCESS(status))
 944                 device->flags.dynamic_status = 1;
 945
 946         /* Presence of _RMV indicates 'removable' */
 947         status = acpi_get_handle(device->handle, "_RMV", &temp);
 948         if (ACPI_SUCCESS(status))
 949                 device->flags.removable = 1;
 950
 951         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 952         status = acpi_get_handle(device->handle, "_EJD", &temp);
 953         if (ACPI_SUCCESS(status))
 954                 device->flags.ejectable = 1;
 955         else {
 956                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
 957                 if (ACPI_SUCCESS(status))
 958                         device->flags.ejectable = 1;
 959         }
 960
 961         /* Presence of _LCK indicates 'lockable' */
 962         status = acpi_get_handle(device->handle, "_LCK", &temp);
 963         if (ACPI_SUCCESS(status))
 964                 device->flags.lockable = 1;
 965
 966         /* Presence of _PS0|_PR0 indicates 'power manageable' */
 967         status = acpi_get_handle(device->handle, "_PS0", &temp);
 968         if (ACPI_FAILURE(status))
 969                 status = acpi_get_handle(device->handle, "_PR0", &temp);
 970         if (ACPI_SUCCESS(status))
 971                 device->flags.power_manageable = 1;
 972
 973         /* TBD: Performance management */
 974
 975         return 0;
 976 }
 977
 978 static void acpi_device_get_busid(struct acpi_device *device)
 979 {
 980         char bus_id[5] = { '?', 0 };
 981         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
 982         int i = 0;
 983
 984         /*
 985          * Bus ID
 986          * ------
 987          * The device's Bus ID is simply the object name.
 988          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
 989          */
 990         if (ACPI_IS_ROOT_DEVICE(device)) {
 991                 strcpy(device->pnp.bus_id, "ACPI");
 992                 return;
 993         }
 994
 995         switch (device->device_type) {
 996         case ACPI_BUS_TYPE_POWER_BUTTON:
 997                 strcpy(device->pnp.bus_id, "PWRF");
 998                 break;
 999         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1000                 strcpy(device->pnp.bus_id, "SLPF");
1001                 break;
1002         default:
1003                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1004                 /* Clean up trailing underscores (if any) */
1005                 for (i = 3; i > 1; i--) {
1006                         if (bus_id[i] == '_')
1007                                 bus_id[i] = '\0';
1008                         else
1009                                 break;
1010                 }
1011                 strcpy(device->pnp.bus_id, bus_id);
1012                 break;
1013         }
1014 }
1015
1016 /*
1017  * acpi_bay_match - see if a device is an ejectable driver bay
1018  *
1019  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1020  * then we can safely call it an ejectable drive bay
1021  */
1022 static int acpi_bay_match(struct acpi_device *device){
1023         acpi_status status;
1024         acpi_handle handle;
1025         acpi_handle tmp;
1026         acpi_handle phandle;
1027
1028         handle = device->handle;
1029
1030         status = acpi_get_handle(handle, "_EJ0", &tmp);
1031         if (ACPI_FAILURE(status))
1032                 return -ENODEV;
1033
1034         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
1035                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
1036                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
1037                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
1038                 return 0;
1039
1040         if (acpi_get_parent(handle, &phandle))
1041                 return -ENODEV;
1042
1043         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
1044                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
1045                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
1046                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
1047                 return 0;
1048
1049         return -ENODEV;
1050 }
1051
1052 /*
1053  * acpi_dock_match - see if a device has a _DCK method
1054  */
1055 static int acpi_dock_match(struct acpi_device *device)
1056 {
1057         acpi_handle tmp;
1058         return acpi_get_handle(device->handle, "_DCK", &tmp);
1059 }
1060
1061 const char *acpi_device_hid(struct acpi_device *device)
1062 {
1063         struct acpi_hardware_id *hid;
1064
1065         if (list_empty(&device->pnp.ids))
1066                 return dummy_hid;
1067
1068         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1069         return hid->id;
1070 }
1071 EXPORT_SYMBOL(acpi_device_hid);
1072
1073 static void acpi_add_id(struct acpi_device *device, const char *dev_id)
1074 {
1075         struct acpi_hardware_id *id;
1076
1077         id = kmalloc(sizeof(*id), GFP_KERNEL);
1078         if (!id)
1079                 return;
1080
1081         id->id = kmalloc(strlen(dev_id) + 1, GFP_KERNEL);
1082         if (!id->id) {
1083                 kfree(id);
1084                 return;
1085         }
1086
1087         strcpy(id->id, dev_id);
1088         list_add_tail(&id->list, &device->pnp.ids);
1089 }
1090
1091 /*
1092  * Old IBM workstations have a DSDT bug wherein the SMBus object
1093  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1094  * prefix.  Work around this.
1095  */
1096 static int acpi_ibm_smbus_match(struct acpi_device *device)
1097 {
1098         acpi_handle h_dummy;
1099         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1100         int result;
1101
1102         if (!dmi_name_in_vendors("IBM"))
1103                 return -ENODEV;
1104
1105         /* Look for SMBS object */
1106         result = acpi_get_name(device->handle, ACPI_SINGLE_NAME, &path);
1107         if (result)
1108                 return result;
1109
1110         if (strcmp("SMBS", path.pointer)) {
1111                 result = -ENODEV;
1112                 goto out;
1113         }
1114
1115         /* Does it have the necessary (but misnamed) methods? */
1116         result = -ENODEV;
1117         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "SBI", &h_dummy)) &&
1118             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBR", &h_dummy)) &&
1119             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBW", &h_dummy)))
1120                 result = 0;
1121 out:
1122         kfree(path.pointer);
1123         return result;
1124 }
1125
1126 static void acpi_device_set_id(struct acpi_device *device)
1127 {
1128         acpi_status status;
1129         struct acpi_device_info *info;
1130         struct acpica_device_id_list *cid_list;
1131         int i;
1132
1133         switch (device->device_type) {
1134         case ACPI_BUS_TYPE_DEVICE:
1135                 if (ACPI_IS_ROOT_DEVICE(device)) {
1136                         acpi_add_id(device, ACPI_SYSTEM_HID);
1137                         break;
1138                 }
1139
1140                 status = acpi_get_object_info(device->handle, &info);
1141                 if (ACPI_FAILURE(status)) {
1142                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1143                         return;
1144                 }
1145
1146                 if (info->valid & ACPI_VALID_HID)
1147                         acpi_add_id(device, info->hardware_id.string);
1148                 if (info->valid & ACPI_VALID_CID) {
1149                         cid_list = &info->compatible_id_list;
1150                         for (i = 0; i < cid_list->count; i++)
1151                                 acpi_add_id(device, cid_list->ids[i].string);
1152                 }
1153 #ifdef CONFIG_PCI_GUESTDEV
1154                 if (info->valid & ACPI_VALID_UID)
1155                         device->pnp.unique_id = kstrdup(info->unique_id.string,
1156                                                         GFP_KERNEL);
1157 #endif
1158                 if (info->valid & ACPI_VALID_ADR) {
1159                         device->pnp.bus_address = info->address;
1160                         device->flags.bus_address = 1;
1161                 }
1162
1163                 kfree(info);
1164
1165                 /*
1166                  * Some devices don't reliably have _HIDs & _CIDs, so add
1167                  * synthetic HIDs to make sure drivers can find them.
1168                  */
1169                 if (acpi_is_video_device(device))
1170                         acpi_add_id(device, ACPI_VIDEO_HID);
1171                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1172                         acpi_add_id(device, ACPI_BAY_HID);
1173                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1174                         acpi_add_id(device, ACPI_DOCK_HID);
1175                 else if (!acpi_ibm_smbus_match(device))
1176                         acpi_add_id(device, ACPI_SMBUS_IBM_HID);
1177                 else if (!acpi_device_hid(device) &&
1178                          ACPI_IS_ROOT_DEVICE(device->parent)) {
1179                         acpi_add_id(device, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1180                         strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1181                         strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1182                 }
1183
1184                 break;
1185         case ACPI_BUS_TYPE_POWER:
1186                 acpi_add_id(device, ACPI_POWER_HID);
1187                 break;
1188         case ACPI_BUS_TYPE_PROCESSOR:
1189                 acpi_add_id(device, ACPI_PROCESSOR_OBJECT_HID);
1190                 break;
1191         case ACPI_BUS_TYPE_THERMAL:
1192                 acpi_add_id(device, ACPI_THERMAL_HID);
1193                 break;
1194         case ACPI_BUS_TYPE_POWER_BUTTON:
1195                 acpi_add_id(device, ACPI_BUTTON_HID_POWERF);
1196                 break;
1197         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1198                 acpi_add_id(device, ACPI_BUTTON_HID_SLEEPF);
1199                 break;
1200         }
1201 }
1202
1203 static int acpi_device_set_context(struct acpi_device *device)
1204 {
1205         acpi_status status;
1206
1207         /*
1208          * Context
1209          * -------
1210          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1211          * resolutions from handle->device very efficient.  Fixed hardware
1212          * devices have no handles, so we skip them.
1213          */
1214         if (!device->handle)
1215                 return 0;
1216
1217         status = acpi_attach_data(device->handle,
1218                                   acpi_bus_data_handler, device);
1219         if (ACPI_SUCCESS(status))
1220                 return 0;
1221
1222         printk(KERN_ERR PREFIX "Error attaching device data\n");
1223         return -ENODEV;
1224 }
1225
1226 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1227 {
1228         if (!dev)
1229                 return -EINVAL;
1230
1231         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1232         device_release_driver(&dev->dev);
1233
1234         if (!rmdevice)
1235                 return 0;
1236
1237         /*
1238          * unbind _ADR-Based Devices when hot removal
1239          */
1240         if (dev->flags.bus_address) {
1241                 if ((dev->parent) && (dev->parent->ops.unbind))
1242                         dev->parent->ops.unbind(dev);
1243         }
1244         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1245
1246         return 0;
1247 }
1248
1249 static int acpi_add_single_object(struct acpi_device **child,
1250                                   acpi_handle handle, int type,
1251                                   unsigned long long sta,
1252                                   struct acpi_bus_ops *ops)
1253 {
1254         int result;
1255         struct acpi_device *device;
1256         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1257
1258         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1259         if (!device) {
1260                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1261                 return -ENOMEM;
1262         }
1263
1264         INIT_LIST_HEAD(&device->pnp.ids);
1265         device->device_type = type;
1266         device->handle = handle;
1267         device->parent = acpi_bus_get_parent(handle);
1268         device->bus_ops = *ops; /* workround for not call .start */
1269         STRUCT_TO_INT(device->status) = sta;
1270
1271         acpi_device_get_busid(device);
1272
1273         /*
1274          * Flags
1275          * -----
1276          * Note that we only look for object handles -- cannot evaluate objects
1277          * until we know the device is present and properly initialized.
1278          */
1279         result = acpi_bus_get_flags(device);
1280         if (result)
1281                 goto end;
1282
1283         /*
1284          * Initialize Device
1285          * -----------------
1286          * TBD: Synch with Core's enumeration/initialization process.
1287          */
1288         acpi_device_set_id(device);
1289
1290         /*
1291          * Power Management
1292          * ----------------
1293          */
1294         if (device->flags.power_manageable) {
1295                 result = acpi_bus_get_power_flags(device);
1296                 if (result)
1297                         goto end;
1298         }
1299
1300         /*
1301          * Wakeup device management
1302          *-----------------------
1303          */
1304         acpi_bus_get_wakeup_device_flags(device);
1305
1306         /*
1307          * Performance Management
1308          * ----------------------
1309          */
1310         if (device->flags.performance_manageable) {
1311                 result = acpi_bus_get_perf_flags(device);
1312                 if (result)
1313                         goto end;
1314         }
1315
1316         if ((result = acpi_device_set_context(device)))
1317                 goto end;
1318
1319         result = acpi_device_register(device);
1320
1321         /*
1322          * Bind _ADR-Based Devices when hot add
1323          */
1324         if (device->flags.bus_address) {
1325                 if (device->parent && device->parent->ops.bind)
1326                         device->parent->ops.bind(device);
1327         }
1328
1329 end:
1330         if (!result) {
1331                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1332                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1333                         "Adding %s [%s] parent %s\n", dev_name(&device->dev),
1334                          (char *) buffer.pointer,
1335                          device->parent ? dev_name(&device->parent->dev) :
1336                                           "(null)"));
1337                 kfree(buffer.pointer);
1338                 *child = device;
1339         } else
1340                 acpi_device_release(&device->dev);
1341
1342         return result;
1343 }
1344
1345 #define ACPI_STA_DEFAULT (ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED | \
1346                           ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING)
1347
1348 static void acpi_bus_add_power_resource(acpi_handle handle)
1349 {
1350         struct acpi_bus_ops ops = {
1351                 .acpi_op_add = 1,
1352                 .acpi_op_start = 1,
1353         };
1354         struct acpi_device *device = NULL;
1355
1356         acpi_bus_get_device(handle, &device);
1357         if (!device)
1358                 acpi_add_single_object(&device, handle, ACPI_BUS_TYPE_POWER,
1359                                         ACPI_STA_DEFAULT, &ops);
1360 }
1361
1362 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1363                                     unsigned long long *sta)
1364 {
1365         acpi_status status;
1366         acpi_object_type acpi_type;
1367
1368         status = acpi_get_type(handle, &acpi_type);
1369         if (ACPI_FAILURE(status))
1370                 return -ENODEV;
1371
1372         switch (acpi_type) {
1373         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1374         case ACPI_TYPE_DEVICE:
1375                 *type = ACPI_BUS_TYPE_DEVICE;
1376                 status = acpi_bus_get_status_handle(handle, sta);
1377                 if (ACPI_FAILURE(status))
1378                         return -ENODEV;
1379                 break;
1380         case ACPI_TYPE_PROCESSOR:
1381                 *type = ACPI_BUS_TYPE_PROCESSOR;
1382                 status = acpi_bus_get_status_handle(handle, sta);
1383                 if (ACPI_FAILURE(status))
1384                         return -ENODEV;
1385                 break;
1386         case ACPI_TYPE_THERMAL:
1387                 *type = ACPI_BUS_TYPE_THERMAL;
1388                 *sta = ACPI_STA_DEFAULT;
1389                 break;
1390         case ACPI_TYPE_POWER:
1391                 *type = ACPI_BUS_TYPE_POWER;
1392                 *sta = ACPI_STA_DEFAULT;
1393                 break;
1394         default:
1395                 return -ENODEV;
1396         }
1397
1398         return 0;
1399 }
1400
1401 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl,
1402                                       void *context, void **return_value)
1403 {
1404         struct acpi_bus_ops *ops = context;
1405         int type;
1406         unsigned long long sta;
1407         struct acpi_device *device;
1408         acpi_status status;
1409         int result;
1410
1411         result = acpi_bus_type_and_status(handle, &type, &sta);
1412         if (result)
1413                 return AE_OK;
1414
1415         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1416             !(sta & ACPI_STA_DEVICE_FUNCTIONING)) {
1417                 struct acpi_device_wakeup wakeup;
1418                 acpi_handle temp;
1419
1420                 status = acpi_get_handle(handle, "_PRW", &temp);
1421                 if (ACPI_SUCCESS(status))
1422                         acpi_bus_extract_wakeup_device_power_package(handle,
1423                                                                      &wakeup);
1424                 return AE_CTRL_DEPTH;
1425         }
1426
1427         /*
1428          * We may already have an acpi_device from a previous enumeration.  If
1429          * so, we needn't add it again, but we may still have to start it.
1430          */
1431         device = NULL;
1432         acpi_bus_get_device(handle, &device);
1433         if (ops->acpi_op_add && !device)
1434                 acpi_add_single_object(&device, handle, type, sta, ops);
1435
1436         if (!device)
1437                 return AE_CTRL_DEPTH;
1438
1439         if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1440                 status = acpi_start_single_object(device);
1441                 if (ACPI_FAILURE(status))
1442                         return AE_CTRL_DEPTH;
1443         }
1444
1445         if (!*return_value)
1446                 *return_value = device;
1447         return AE_OK;
1448 }
1449
1450 static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops,
1451                          struct acpi_device **child)
1452 {
1453         acpi_status status;
1454         void *device = NULL;
1455
1456         status = acpi_bus_check_add(handle, 0, ops, &device);
1457         if (ACPI_SUCCESS(status))
1458                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1459                                     acpi_bus_check_add, NULL, ops, &device);
1460
1461         if (child)
1462                 *child = device;
1463
1464         if (device)
1465                 return 0;
1466         else
1467                 return -ENODEV;
1468 }
1469
1470 /*
1471  * acpi_bus_add and acpi_bus_start
1472  *
1473  * scan a given ACPI tree and (probably recently hot-plugged)
1474  * create and add or starts found devices.
1475  *
1476  * If no devices were found -ENODEV is returned which does not
1477  * mean that this is a real error, there just have been no suitable
1478  * ACPI objects in the table trunk from which the kernel could create
1479  * a device and add/start an appropriate driver.
1480  */
1481
1482 int
1483 acpi_bus_add(struct acpi_device **child,
1484              struct acpi_device *parent, acpi_handle handle, int type)
1485 {
1486         struct acpi_bus_ops ops;
1487
1488         memset(&ops, 0, sizeof(ops));
1489         ops.acpi_op_add = 1;
1490
1491         return acpi_bus_scan(handle, &ops, child);
1492 }
1493 EXPORT_SYMBOL(acpi_bus_add);
1494
1495 int acpi_bus_start(struct acpi_device *device)
1496 {
1497         struct acpi_bus_ops ops;
1498         int result;
1499
1500         if (!device)
1501                 return -EINVAL;
1502
1503         memset(&ops, 0, sizeof(ops));
1504         ops.acpi_op_start = 1;
1505
1506         result = acpi_bus_scan(device->handle, &ops, NULL);
1507
1508         acpi_update_all_gpes();
1509
1510         return result;
1511 }
1512 EXPORT_SYMBOL(acpi_bus_start);
1513
1514 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1515 {
1516         acpi_status status;
1517         struct acpi_device *parent, *child;
1518         acpi_handle phandle, chandle;
1519         acpi_object_type type;
1520         u32 level = 1;
1521         int err = 0;
1522
1523         parent = start;
1524         phandle = start->handle;
1525         child = chandle = NULL;
1526
1527         while ((level > 0) && parent && (!err)) {
1528                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1529                                               chandle, &chandle);
1530
1531                 /*
1532                  * If this scope is exhausted then move our way back up.
1533                  */
1534                 if (ACPI_FAILURE(status)) {
1535                         level--;
1536                         chandle = phandle;
1537                         acpi_get_parent(phandle, &phandle);
1538                         child = parent;
1539                         parent = parent->parent;
1540
1541                         if (level == 0)
1542                                 err = acpi_bus_remove(child, rmdevice);
1543                         else
1544                                 err = acpi_bus_remove(child, 1);
1545
1546                         continue;
1547                 }
1548
1549                 status = acpi_get_type(chandle, &type);
1550                 if (ACPI_FAILURE(status)) {
1551                         continue;
1552                 }
1553                 /*
1554                  * If there is a device corresponding to chandle then
1555                  * parse it (depth-first).
1556                  */
1557                 if (acpi_bus_get_device(chandle, &child) == 0) {
1558                         level++;
1559                         phandle = chandle;
1560                         chandle = NULL;
1561                         parent = child;
1562                 }
1563                 continue;
1564         }
1565         return err;
1566 }
1567 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1568
1569 static int acpi_bus_scan_fixed(void)
1570 {
1571         int result = 0;
1572         struct acpi_device *device = NULL;
1573         struct acpi_bus_ops ops;
1574
1575         memset(&ops, 0, sizeof(ops));
1576         ops.acpi_op_add = 1;
1577         ops.acpi_op_start = 1;
1578
1579         /*
1580          * Enumerate all fixed-feature devices.
1581          */
1582         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1583                 result = acpi_add_single_object(&device, NULL,
1584                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1585                                                 ACPI_STA_DEFAULT,
1586                                                 &ops);
1587         }
1588
1589         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1590                 result = acpi_add_single_object(&device, NULL,
1591                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1592                                                 ACPI_STA_DEFAULT,
1593                                                 &ops);
1594         }
1595
1596         return result;
1597 }
1598
1599 int __init acpi_scan_init(void)
1600 {
1601         int result;
1602         struct acpi_bus_ops ops;
1603
1604         memset(&ops, 0, sizeof(ops));
1605         ops.acpi_op_add = 1;
1606         ops.acpi_op_start = 1;
1607
1608         result = bus_register(&acpi_bus_type);
1609         if (result) {
1610                 /* We don't want to quit even if we failed to add suspend/resume */
1611                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1612         }
1613
1614         acpi_power_init();
1615
1616         /*
1617          * Enumerate devices in the ACPI namespace.
1618          */
1619         result = acpi_bus_scan(ACPI_ROOT_OBJECT, &ops, &acpi_root);
1620
1621         if (!result)
1622                 result = acpi_bus_scan_fixed();
1623
1624         if (result)
1625                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1626         else
1627                 acpi_update_all_gpes();
1628
1629         return result;
1630 }