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(struct acpi_device *device,
 729                                              union acpi_object *package)
 730 {
 731         int i = 0;
 732         union acpi_object *element = NULL;
 733
 734         if (!device || !package || (package->package.count < 2))
 735                 return AE_BAD_PARAMETER;
 736
 737         element = &(package->package.elements[0]);
 738         if (!element)
 739                 return AE_BAD_PARAMETER;
 740         if (element->type == ACPI_TYPE_PACKAGE) {
 741                 if ((element->package.count < 2) ||
 742                     (element->package.elements[0].type !=
 743                      ACPI_TYPE_LOCAL_REFERENCE)
 744                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 745                         return AE_BAD_DATA;
 746                 device->wakeup.gpe_device =
 747                     element->package.elements[0].reference.handle;
 748                 device->wakeup.gpe_number =
 749                     (u32) element->package.elements[1].integer.value;
 750         } else if (element->type == ACPI_TYPE_INTEGER) {
 751                 device->wakeup.gpe_number = element->integer.value;
 752         } else
 753                 return AE_BAD_DATA;
 754
 755         element = &(package->package.elements[1]);
 756         if (element->type != ACPI_TYPE_INTEGER) {
 757                 return AE_BAD_DATA;
 758         }
 759         device->wakeup.sleep_state = element->integer.value;
 760
 761         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
 762                 return AE_NO_MEMORY;
 763         }
 764         device->wakeup.resources.count = package->package.count - 2;
 765         for (i = 0; i < device->wakeup.resources.count; i++) {
 766                 element = &(package->package.elements[i + 2]);
 767                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
 768                         return AE_BAD_DATA;
 769
 770                 device->wakeup.resources.handles[i] = element->reference.handle;
 771         }
 772
 773         acpi_gpe_can_wake(device->wakeup.gpe_device, device->wakeup.gpe_number);
 774
 775         return AE_OK;
 776 }
 777
 778 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
 779 {
 780         struct acpi_device_id button_device_ids[] = {
 781                 {"PNP0C0D", 0},
 782                 {"PNP0C0C", 0},
 783                 {"PNP0C0E", 0},
 784                 {"", 0},
 785         };
 786         acpi_status status;
 787         acpi_event_status event_status;
 788
 789         device->wakeup.run_wake_count = 0;
 790         device->wakeup.flags.notifier_present = 0;
 791
 792         /* Power button, Lid switch always enable wakeup */
 793         if (!acpi_match_device_ids(device, button_device_ids)) {
 794                 device->wakeup.flags.run_wake = 1;
 795                 device->wakeup.flags.always_enabled = 1;
 796                 return;
 797         }
 798
 799         status = acpi_get_gpe_status(device->wakeup.gpe_device,
 800                                         device->wakeup.gpe_number,
 801                                                 &event_status);
 802         if (status == AE_OK)
 803                 device->wakeup.flags.run_wake =
 804                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
 805 }
 806
 807 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 808 {
 809         acpi_status status = 0;
 810         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 811         union acpi_object *package = NULL;
 812         int psw_error;
 813
 814         /* _PRW */
 815         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
 816         if (ACPI_FAILURE(status)) {
 817                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 818                 goto end;
 819         }
 820
 821         package = (union acpi_object *)buffer.pointer;
 822         status = acpi_bus_extract_wakeup_device_power_package(device, package);
 823         if (ACPI_FAILURE(status)) {
 824                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
 825                 goto end;
 826         }
 827
 828         kfree(buffer.pointer);
 829
 830         device->wakeup.flags.valid = 1;
 831         device->wakeup.prepare_count = 0;
 832         acpi_bus_set_run_wake_flags(device);
 833         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
 834          * system for the ACPI device with the _PRW object.
 835          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 836          * So it is necessary to call _DSW object first. Only when it is not
 837          * present will the _PSW object used.
 838          */
 839         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
 840         if (psw_error)
 841                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 842                                 "error in _DSW or _PSW evaluation\n"));
 843
 844 end:
 845         if (ACPI_FAILURE(status))
 846                 device->flags.wake_capable = 0;
 847         return 0;
 848 }
 849
 850 static int acpi_bus_get_power_flags(struct acpi_device *device)
 851 {
 852         acpi_status status = 0;
 853         acpi_handle handle = NULL;
 854         u32 i = 0;
 855
 856
 857         /*
 858          * Power Management Flags
 859          */
 860         status = acpi_get_handle(device->handle, "_PSC", &handle);
 861         if (ACPI_SUCCESS(status))
 862                 device->power.flags.explicit_get = 1;
 863         status = acpi_get_handle(device->handle, "_IRC", &handle);
 864         if (ACPI_SUCCESS(status))
 865                 device->power.flags.inrush_current = 1;
 866
 867         /*
 868          * Enumerate supported power management states
 869          */
 870         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
 871                 struct acpi_device_power_state *ps = &device->power.states[i];
 872                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
 873
 874                 /* Evaluate "_PRx" to se if power resources are referenced */
 875                 acpi_evaluate_reference(device->handle, object_name, NULL,
 876                                         &ps->resources);
 877                 if (ps->resources.count) {
 878                         device->power.flags.power_resources = 1;
 879                         ps->flags.valid = 1;
 880                 }
 881
 882                 /* Evaluate "_PSx" to see if we can do explicit sets */
 883                 object_name[2] = 'S';
 884                 status = acpi_get_handle(device->handle, object_name, &handle);
 885                 if (ACPI_SUCCESS(status)) {
 886                         ps->flags.explicit_set = 1;
 887                         ps->flags.valid = 1;
 888                 }
 889
 890                 /* State is valid if we have some power control */
 891                 if (ps->resources.count || ps->flags.explicit_set)
 892                         ps->flags.valid = 1;
 893
 894                 ps->power = -1; /* Unknown - driver assigned */
 895                 ps->latency = -1;       /* Unknown - driver assigned */
 896         }
 897
 898         /* Set defaults for D0 and D3 states (always valid) */
 899         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 900         device->power.states[ACPI_STATE_D0].power = 100;
 901         device->power.states[ACPI_STATE_D3].flags.valid = 1;
 902         device->power.states[ACPI_STATE_D3].power = 0;
 903
 904         /* TBD: System wake support and resource requirements. */
 905
 906         device->power.state = ACPI_STATE_UNKNOWN;
 907         acpi_bus_get_power(device->handle, &(device->power.state));
 908
 909         return 0;
 910 }
 911
 912 static int acpi_bus_get_flags(struct acpi_device *device)
 913 {
 914         acpi_status status = AE_OK;
 915         acpi_handle temp = NULL;
 916
 917
 918         /* Presence of _STA indicates 'dynamic_status' */
 919         status = acpi_get_handle(device->handle, "_STA", &temp);
 920         if (ACPI_SUCCESS(status))
 921                 device->flags.dynamic_status = 1;
 922
 923         /* Presence of _RMV indicates 'removable' */
 924         status = acpi_get_handle(device->handle, "_RMV", &temp);
 925         if (ACPI_SUCCESS(status))
 926                 device->flags.removable = 1;
 927
 928         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 929         status = acpi_get_handle(device->handle, "_EJD", &temp);
 930         if (ACPI_SUCCESS(status))
 931                 device->flags.ejectable = 1;
 932         else {
 933                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
 934                 if (ACPI_SUCCESS(status))
 935                         device->flags.ejectable = 1;
 936         }
 937
 938         /* Presence of _LCK indicates 'lockable' */
 939         status = acpi_get_handle(device->handle, "_LCK", &temp);
 940         if (ACPI_SUCCESS(status))
 941                 device->flags.lockable = 1;
 942
 943         /* Presence of _PS0|_PR0 indicates 'power manageable' */
 944         status = acpi_get_handle(device->handle, "_PS0", &temp);
 945         if (ACPI_FAILURE(status))
 946                 status = acpi_get_handle(device->handle, "_PR0", &temp);
 947         if (ACPI_SUCCESS(status))
 948                 device->flags.power_manageable = 1;
 949
 950         /* Presence of _PRW indicates wake capable */
 951         status = acpi_get_handle(device->handle, "_PRW", &temp);
 952         if (ACPI_SUCCESS(status))
 953                 device->flags.wake_capable = 1;
 954
 955         /* TBD: Performance management */
 956
 957         return 0;
 958 }
 959
 960 static void acpi_device_get_busid(struct acpi_device *device)
 961 {
 962         char bus_id[5] = { '?', 0 };
 963         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
 964         int i = 0;
 965
 966         /*
 967          * Bus ID
 968          * ------
 969          * The device's Bus ID is simply the object name.
 970          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
 971          */
 972         if (ACPI_IS_ROOT_DEVICE(device)) {
 973                 strcpy(device->pnp.bus_id, "ACPI");
 974                 return;
 975         }
 976
 977         switch (device->device_type) {
 978         case ACPI_BUS_TYPE_POWER_BUTTON:
 979                 strcpy(device->pnp.bus_id, "PWRF");
 980                 break;
 981         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 982                 strcpy(device->pnp.bus_id, "SLPF");
 983                 break;
 984         default:
 985                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
 986                 /* Clean up trailing underscores (if any) */
 987                 for (i = 3; i > 1; i--) {
 988                         if (bus_id[i] == '_')
 989                                 bus_id[i] = '\0';
 990                         else
 991                                 break;
 992                 }
 993                 strcpy(device->pnp.bus_id, bus_id);
 994                 break;
 995         }
 996 }
 997
 998 /*
 999  * acpi_bay_match - see if a device is an ejectable driver bay
1000  *
1001  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1002  * then we can safely call it an ejectable drive bay
1003  */
1004 static int acpi_bay_match(struct acpi_device *device){
1005         acpi_status status;
1006         acpi_handle handle;
1007         acpi_handle tmp;
1008         acpi_handle phandle;
1009
1010         handle = device->handle;
1011
1012         status = acpi_get_handle(handle, "_EJ0", &tmp);
1013         if (ACPI_FAILURE(status))
1014                 return -ENODEV;
1015
1016         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
1017                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
1018                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
1019                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
1020                 return 0;
1021
1022         if (acpi_get_parent(handle, &phandle))
1023                 return -ENODEV;
1024
1025         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
1026                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
1027                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
1028                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
1029                 return 0;
1030
1031         return -ENODEV;
1032 }
1033
1034 /*
1035  * acpi_dock_match - see if a device has a _DCK method
1036  */
1037 static int acpi_dock_match(struct acpi_device *device)
1038 {
1039         acpi_handle tmp;
1040         return acpi_get_handle(device->handle, "_DCK", &tmp);
1041 }
1042
1043 const char *acpi_device_hid(struct acpi_device *device)
1044 {
1045         struct acpi_hardware_id *hid;
1046
1047         if (list_empty(&device->pnp.ids))
1048                 return dummy_hid;
1049
1050         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1051         return hid->id;
1052 }
1053 EXPORT_SYMBOL(acpi_device_hid);
1054
1055 static void acpi_add_id(struct acpi_device *device, const char *dev_id)
1056 {
1057         struct acpi_hardware_id *id;
1058
1059         id = kmalloc(sizeof(*id), GFP_KERNEL);
1060         if (!id)
1061                 return;
1062
1063         id->id = kmalloc(strlen(dev_id) + 1, GFP_KERNEL);
1064         if (!id->id) {
1065                 kfree(id);
1066                 return;
1067         }
1068
1069         strcpy(id->id, dev_id);
1070         list_add_tail(&id->list, &device->pnp.ids);
1071 }
1072
1073 /*
1074  * Old IBM workstations have a DSDT bug wherein the SMBus object
1075  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1076  * prefix.  Work around this.
1077  */
1078 static int acpi_ibm_smbus_match(struct acpi_device *device)
1079 {
1080         acpi_handle h_dummy;
1081         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1082         int result;
1083
1084         if (!dmi_name_in_vendors("IBM"))
1085                 return -ENODEV;
1086
1087         /* Look for SMBS object */
1088         result = acpi_get_name(device->handle, ACPI_SINGLE_NAME, &path);
1089         if (result)
1090                 return result;
1091
1092         if (strcmp("SMBS", path.pointer)) {
1093                 result = -ENODEV;
1094                 goto out;
1095         }
1096
1097         /* Does it have the necessary (but misnamed) methods? */
1098         result = -ENODEV;
1099         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "SBI", &h_dummy)) &&
1100             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBR", &h_dummy)) &&
1101             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBW", &h_dummy)))
1102                 result = 0;
1103 out:
1104         kfree(path.pointer);
1105         return result;
1106 }
1107
1108 static void acpi_device_set_id(struct acpi_device *device)
1109 {
1110         acpi_status status;
1111         struct acpi_device_info *info;
1112         struct acpica_device_id_list *cid_list;
1113         int i;
1114
1115         switch (device->device_type) {
1116         case ACPI_BUS_TYPE_DEVICE:
1117                 if (ACPI_IS_ROOT_DEVICE(device)) {
1118                         acpi_add_id(device, ACPI_SYSTEM_HID);
1119                         break;
1120                 }
1121
1122                 status = acpi_get_object_info(device->handle, &info);
1123                 if (ACPI_FAILURE(status)) {
1124                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1125                         return;
1126                 }
1127
1128                 if (info->valid & ACPI_VALID_HID)
1129                         acpi_add_id(device, info->hardware_id.string);
1130                 if (info->valid & ACPI_VALID_CID) {
1131                         cid_list = &info->compatible_id_list;
1132                         for (i = 0; i < cid_list->count; i++)
1133                                 acpi_add_id(device, cid_list->ids[i].string);
1134                 }
1135 #ifdef CONFIG_PCI_GUESTDEV
1136                 if (info->valid & ACPI_VALID_UID)
1137                         device->pnp.unique_id = kstrdup(info->unique_id.string,
1138                                                         GFP_KERNEL);
1139 #endif
1140                 if (info->valid & ACPI_VALID_ADR) {
1141                         device->pnp.bus_address = info->address;
1142                         device->flags.bus_address = 1;
1143                 }
1144
1145                 kfree(info);
1146
1147                 /*
1148                  * Some devices don't reliably have _HIDs & _CIDs, so add
1149                  * synthetic HIDs to make sure drivers can find them.
1150                  */
1151                 if (acpi_is_video_device(device))
1152                         acpi_add_id(device, ACPI_VIDEO_HID);
1153                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1154                         acpi_add_id(device, ACPI_BAY_HID);
1155                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1156                         acpi_add_id(device, ACPI_DOCK_HID);
1157                 else if (!acpi_ibm_smbus_match(device))
1158                         acpi_add_id(device, ACPI_SMBUS_IBM_HID);
1159                 else if (!acpi_device_hid(device) &&
1160                          ACPI_IS_ROOT_DEVICE(device->parent)) {
1161                         acpi_add_id(device, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1162                         strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1163                         strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1164                 }
1165
1166                 break;
1167         case ACPI_BUS_TYPE_POWER:
1168                 acpi_add_id(device, ACPI_POWER_HID);
1169                 break;
1170         case ACPI_BUS_TYPE_PROCESSOR:
1171                 acpi_add_id(device, ACPI_PROCESSOR_OBJECT_HID);
1172                 break;
1173         case ACPI_BUS_TYPE_THERMAL:
1174                 acpi_add_id(device, ACPI_THERMAL_HID);
1175                 break;
1176         case ACPI_BUS_TYPE_POWER_BUTTON:
1177                 acpi_add_id(device, ACPI_BUTTON_HID_POWERF);
1178                 break;
1179         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1180                 acpi_add_id(device, ACPI_BUTTON_HID_SLEEPF);
1181                 break;
1182         }
1183 }
1184
1185 static int acpi_device_set_context(struct acpi_device *device)
1186 {
1187         acpi_status status;
1188
1189         /*
1190          * Context
1191          * -------
1192          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1193          * resolutions from handle->device very efficient.  Fixed hardware
1194          * devices have no handles, so we skip them.
1195          */
1196         if (!device->handle)
1197                 return 0;
1198
1199         status = acpi_attach_data(device->handle,
1200                                   acpi_bus_data_handler, device);
1201         if (ACPI_SUCCESS(status))
1202                 return 0;
1203
1204         printk(KERN_ERR PREFIX "Error attaching device data\n");
1205         return -ENODEV;
1206 }
1207
1208 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1209 {
1210         if (!dev)
1211                 return -EINVAL;
1212
1213         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1214         device_release_driver(&dev->dev);
1215
1216         if (!rmdevice)
1217                 return 0;
1218
1219         /*
1220          * unbind _ADR-Based Devices when hot removal
1221          */
1222         if (dev->flags.bus_address) {
1223                 if ((dev->parent) && (dev->parent->ops.unbind))
1224                         dev->parent->ops.unbind(dev);
1225         }
1226         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1227
1228         return 0;
1229 }
1230
1231 static int acpi_add_single_object(struct acpi_device **child,
1232                                   acpi_handle handle, int type,
1233                                   unsigned long long sta,
1234                                   struct acpi_bus_ops *ops)
1235 {
1236         int result;
1237         struct acpi_device *device;
1238         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1239
1240         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1241         if (!device) {
1242                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1243                 return -ENOMEM;
1244         }
1245
1246         INIT_LIST_HEAD(&device->pnp.ids);
1247         device->device_type = type;
1248         device->handle = handle;
1249         device->parent = acpi_bus_get_parent(handle);
1250         device->bus_ops = *ops; /* workround for not call .start */
1251         STRUCT_TO_INT(device->status) = sta;
1252
1253         acpi_device_get_busid(device);
1254
1255         /*
1256          * Flags
1257          * -----
1258          * Note that we only look for object handles -- cannot evaluate objects
1259          * until we know the device is present and properly initialized.
1260          */
1261         result = acpi_bus_get_flags(device);
1262         if (result)
1263                 goto end;
1264
1265         /*
1266          * Initialize Device
1267          * -----------------
1268          * TBD: Synch with Core's enumeration/initialization process.
1269          */
1270         acpi_device_set_id(device);
1271
1272         /*
1273          * Power Management
1274          * ----------------
1275          */
1276         if (device->flags.power_manageable) {
1277                 result = acpi_bus_get_power_flags(device);
1278                 if (result)
1279                         goto end;
1280         }
1281
1282         /*
1283          * Wakeup device management
1284          *-----------------------
1285          */
1286         if (device->flags.wake_capable) {
1287                 result = acpi_bus_get_wakeup_device_flags(device);
1288                 if (result)
1289                         goto end;
1290         }
1291
1292         /*
1293          * Performance Management
1294          * ----------------------
1295          */
1296         if (device->flags.performance_manageable) {
1297                 result = acpi_bus_get_perf_flags(device);
1298                 if (result)
1299                         goto end;
1300         }
1301
1302         if ((result = acpi_device_set_context(device)))
1303                 goto end;
1304
1305         result = acpi_device_register(device);
1306
1307         /*
1308          * Bind _ADR-Based Devices when hot add
1309          */
1310         if (device->flags.bus_address) {
1311                 if (device->parent && device->parent->ops.bind)
1312                         device->parent->ops.bind(device);
1313         }
1314
1315 end:
1316         if (!result) {
1317                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1318                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1319                         "Adding %s [%s] parent %s\n", dev_name(&device->dev),
1320                          (char *) buffer.pointer,
1321                          device->parent ? dev_name(&device->parent->dev) :
1322                                           "(null)"));
1323                 kfree(buffer.pointer);
1324                 *child = device;
1325         } else
1326                 acpi_device_release(&device->dev);
1327
1328         return result;
1329 }
1330
1331 #define ACPI_STA_DEFAULT (ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED | \
1332                           ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING)
1333
1334 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1335                                     unsigned long long *sta)
1336 {
1337         acpi_status status;
1338         acpi_object_type acpi_type;
1339
1340         status = acpi_get_type(handle, &acpi_type);
1341         if (ACPI_FAILURE(status))
1342                 return -ENODEV;
1343
1344         switch (acpi_type) {
1345         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1346         case ACPI_TYPE_DEVICE:
1347                 *type = ACPI_BUS_TYPE_DEVICE;
1348                 status = acpi_bus_get_status_handle(handle, sta);
1349                 if (ACPI_FAILURE(status))
1350                         return -ENODEV;
1351                 break;
1352         case ACPI_TYPE_PROCESSOR:
1353                 *type = ACPI_BUS_TYPE_PROCESSOR;
1354                 status = acpi_bus_get_status_handle(handle, sta);
1355                 if (ACPI_FAILURE(status))
1356                         return -ENODEV;
1357                 break;
1358         case ACPI_TYPE_THERMAL:
1359                 *type = ACPI_BUS_TYPE_THERMAL;
1360                 *sta = ACPI_STA_DEFAULT;
1361                 break;
1362         case ACPI_TYPE_POWER:
1363                 *type = ACPI_BUS_TYPE_POWER;
1364                 *sta = ACPI_STA_DEFAULT;
1365                 break;
1366         default:
1367                 return -ENODEV;
1368         }
1369
1370         return 0;
1371 }
1372
1373 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl,
1374                                       void *context, void **return_value)
1375 {
1376         struct acpi_bus_ops *ops = context;
1377         int type;
1378         unsigned long long sta;
1379         struct acpi_device *device;
1380         acpi_status status;
1381         int result;
1382
1383         result = acpi_bus_type_and_status(handle, &type, &sta);
1384         if (result)
1385                 return AE_OK;
1386
1387         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1388             !(sta & ACPI_STA_DEVICE_FUNCTIONING))
1389                 return AE_CTRL_DEPTH;
1390
1391         /*
1392          * We may already have an acpi_device from a previous enumeration.  If
1393          * so, we needn't add it again, but we may still have to start it.
1394          */
1395         device = NULL;
1396         acpi_bus_get_device(handle, &device);
1397         if (ops->acpi_op_add && !device)
1398                 acpi_add_single_object(&device, handle, type, sta, ops);
1399
1400         if (!device)
1401                 return AE_CTRL_DEPTH;
1402
1403         if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1404                 status = acpi_start_single_object(device);
1405                 if (ACPI_FAILURE(status))
1406                         return AE_CTRL_DEPTH;
1407         }
1408
1409         if (!*return_value)
1410                 *return_value = device;
1411         return AE_OK;
1412 }
1413
1414 static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops,
1415                          struct acpi_device **child)
1416 {
1417         acpi_status status;
1418         void *device = NULL;
1419
1420         status = acpi_bus_check_add(handle, 0, ops, &device);
1421         if (ACPI_SUCCESS(status))
1422                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1423                                     acpi_bus_check_add, NULL, ops, &device);
1424
1425         if (child)
1426                 *child = device;
1427
1428         if (device)
1429                 return 0;
1430         else
1431                 return -ENODEV;
1432 }
1433
1434 /*
1435  * acpi_bus_add and acpi_bus_start
1436  *
1437  * scan a given ACPI tree and (probably recently hot-plugged)
1438  * create and add or starts found devices.
1439  *
1440  * If no devices were found -ENODEV is returned which does not
1441  * mean that this is a real error, there just have been no suitable
1442  * ACPI objects in the table trunk from which the kernel could create
1443  * a device and add/start an appropriate driver.
1444  */
1445
1446 int
1447 acpi_bus_add(struct acpi_device **child,
1448              struct acpi_device *parent, acpi_handle handle, int type)
1449 {
1450         struct acpi_bus_ops ops;
1451
1452         memset(&ops, 0, sizeof(ops));
1453         ops.acpi_op_add = 1;
1454
1455         return acpi_bus_scan(handle, &ops, child);
1456 }
1457 EXPORT_SYMBOL(acpi_bus_add);
1458
1459 int acpi_bus_start(struct acpi_device *device)
1460 {
1461         struct acpi_bus_ops ops;
1462         int result;
1463
1464         if (!device)
1465                 return -EINVAL;
1466
1467         memset(&ops, 0, sizeof(ops));
1468         ops.acpi_op_start = 1;
1469
1470         result = acpi_bus_scan(device->handle, &ops, NULL);
1471
1472         acpi_update_gpes();
1473
1474         return result;
1475 }
1476 EXPORT_SYMBOL(acpi_bus_start);
1477
1478 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1479 {
1480         acpi_status status;
1481         struct acpi_device *parent, *child;
1482         acpi_handle phandle, chandle;
1483         acpi_object_type type;
1484         u32 level = 1;
1485         int err = 0;
1486
1487         parent = start;
1488         phandle = start->handle;
1489         child = chandle = NULL;
1490
1491         while ((level > 0) && parent && (!err)) {
1492                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1493                                               chandle, &chandle);
1494
1495                 /*
1496                  * If this scope is exhausted then move our way back up.
1497                  */
1498                 if (ACPI_FAILURE(status)) {
1499                         level--;
1500                         chandle = phandle;
1501                         acpi_get_parent(phandle, &phandle);
1502                         child = parent;
1503                         parent = parent->parent;
1504
1505                         if (level == 0)
1506                                 err = acpi_bus_remove(child, rmdevice);
1507                         else
1508                                 err = acpi_bus_remove(child, 1);
1509
1510                         continue;
1511                 }
1512
1513                 status = acpi_get_type(chandle, &type);
1514                 if (ACPI_FAILURE(status)) {
1515                         continue;
1516                 }
1517                 /*
1518                  * If there is a device corresponding to chandle then
1519                  * parse it (depth-first).
1520                  */
1521                 if (acpi_bus_get_device(chandle, &child) == 0) {
1522                         level++;
1523                         phandle = chandle;
1524                         chandle = NULL;
1525                         parent = child;
1526                 }
1527                 continue;
1528         }
1529         return err;
1530 }
1531 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1532
1533 static int acpi_bus_scan_fixed(void)
1534 {
1535         int result = 0;
1536         struct acpi_device *device = NULL;
1537         struct acpi_bus_ops ops;
1538
1539         memset(&ops, 0, sizeof(ops));
1540         ops.acpi_op_add = 1;
1541         ops.acpi_op_start = 1;
1542
1543         /*
1544          * Enumerate all fixed-feature devices.
1545          */
1546         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1547                 result = acpi_add_single_object(&device, NULL,
1548                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1549                                                 ACPI_STA_DEFAULT,
1550                                                 &ops);
1551         }
1552
1553         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1554                 result = acpi_add_single_object(&device, NULL,
1555                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1556                                                 ACPI_STA_DEFAULT,
1557                                                 &ops);
1558         }
1559
1560         return result;
1561 }
1562
1563 int __init acpi_scan_init(void)
1564 {
1565         int result;
1566         struct acpi_bus_ops ops;
1567
1568         memset(&ops, 0, sizeof(ops));
1569         ops.acpi_op_add = 1;
1570         ops.acpi_op_start = 1;
1571
1572         result = bus_register(&acpi_bus_type);
1573         if (result) {
1574                 /* We don't want to quit even if we failed to add suspend/resume */
1575                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1576         }
1577
1578         /*
1579          * Enumerate devices in the ACPI namespace.
1580          */
1581         result = acpi_bus_scan(ACPI_ROOT_OBJECT, &ops, &acpi_root);
1582
1583         if (!result)
1584                 result = acpi_bus_scan_fixed();
1585
1586         if (result)
1587                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1588         else
1589                 acpi_update_gpes();
1590
1591         return result;
1592 }