drivers/acpi/scan.c

   1 /*
   2  * scan.c - support for transforming the ACPI namespace into individual objects
   3  */
   4
   5 #include <linux/module.h>
   6 #include <linux/init.h>
   7 #include <linux/kernel.h>
   8 #include <linux/acpi.h>
   9 #include <linux/signal.h>
  10 #include <linux/kthread.h>
  11 #include <linux/dmi.h>
  12
  13 #include <acpi/acpi_drivers.h>
  14
  15 #include "internal.h"
  16
  17 #define _COMPONENT              ACPI_BUS_COMPONENT
  18 ACPI_MODULE_NAME("scan");
  19 #define STRUCT_TO_INT(s)        (*((int*)&s))
  20 extern struct acpi_device *acpi_root;
  21
  22 #define ACPI_BUS_CLASS                  "system_bus"
  23 #define ACPI_BUS_HID                    "LNXSYBUS"
  24 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  25
  26 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
  27
  28 static LIST_HEAD(acpi_device_list);
  29 static LIST_HEAD(acpi_bus_id_list);
  30 DEFINE_MUTEX(acpi_device_lock);
  31 LIST_HEAD(acpi_wakeup_device_list);
  32
  33 struct acpi_device_bus_id{
  34         char bus_id[15];
  35         unsigned int instance_no;
  36         struct list_head node;
  37 };
  38
  39 /*
  40  * Creates hid/cid(s) string needed for modalias and uevent
  41  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
  42  * char *modalias: "acpi:IBM0001:ACPI0001"
  43 */
  44 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
  45                            int size)
  46 {
  47         int len;
  48         int count;
  49         struct acpi_hardware_id *id;
  50
  51         len = snprintf(modalias, size, "acpi:");
  52         size -= len;
  53
  54         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
  55                 count = snprintf(&modalias[len], size, "%s:", id->id);
  56                 if (count < 0 || count >= size)
  57                         return -EINVAL;
  58                 len += count;
  59                 size -= count;
  60         }
  61
  62         modalias[len] = '\0';
  63         return len;
  64 }
  65
  66 static ssize_t
  67 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
  68         struct acpi_device *acpi_dev = to_acpi_device(dev);
  69         int len;
  70
  71         /* Device has no HID and no CID or string is >1024 */
  72         len = create_modalias(acpi_dev, buf, 1024);
  73         if (len <= 0)
  74                 return 0;
  75         buf[len++] = '\n';
  76         return len;
  77 }
  78 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
  79
  80 static void acpi_bus_hot_remove_device(void *context)
  81 {
  82         struct acpi_device *device;
  83         acpi_handle handle = context;
  84         struct acpi_object_list arg_list;
  85         union acpi_object arg;
  86         acpi_status status = AE_OK;
  87
  88         if (acpi_bus_get_device(handle, &device))
  89                 return;
  90
  91         if (!device)
  92                 return;
  93
  94         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
  95                 "Hot-removing device %s...\n", dev_name(&device->dev)));
  96
  97         if (acpi_bus_trim(device, 1)) {
  98                 printk(KERN_ERR PREFIX
  99                                 "Removing device failed\n");
 100                 return;
 101         }
 102
 103         /* power off device */
 104         status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
 105         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
 106                 printk(KERN_WARNING PREFIX
 107                                 "Power-off device failed\n");
 108
 109         if (device->flags.lockable) {
 110                 arg_list.count = 1;
 111                 arg_list.pointer = &arg;
 112                 arg.type = ACPI_TYPE_INTEGER;
 113                 arg.integer.value = 0;
 114                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
 115         }
 116
 117         arg_list.count = 1;
 118         arg_list.pointer = &arg;
 119         arg.type = ACPI_TYPE_INTEGER;
 120         arg.integer.value = 1;
 121
 122         /*
 123          * TBD: _EJD support.
 124          */
 125         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
 126         if (ACPI_FAILURE(status))
 127                 printk(KERN_WARNING PREFIX
 128                                 "Eject device failed\n");
 129
 130         return;
 131 }
 132
 133 static ssize_t
 134 acpi_eject_store(struct device *d, struct device_attribute *attr,
 135                 const char *buf, size_t count)
 136 {
 137         int ret = count;
 138         acpi_status status;
 139         acpi_object_type type = 0;
 140         struct acpi_device *acpi_device = to_acpi_device(d);
 141
 142         if ((!count) || (buf[0] != '1')) {
 143                 return -EINVAL;
 144         }
 145 #ifndef FORCE_EJECT
 146         if (acpi_device->driver == NULL) {
 147                 ret = -ENODEV;
 148                 goto err;
 149         }
 150 #endif
 151         status = acpi_get_type(acpi_device->handle, &type);
 152         if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
 153                 ret = -ENODEV;
 154                 goto err;
 155         }
 156
 157         acpi_os_hotplug_execute(acpi_bus_hot_remove_device, acpi_device->handle);
 158 err:
 159         return ret;
 160 }
 161
 162 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 163
 164 static ssize_t
 165 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 166         struct acpi_device *acpi_dev = to_acpi_device(dev);
 167
 168         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
 169 }
 170 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 171
 172 #ifdef CONFIG_PCI_GUESTDEV
 173 static ssize_t
 174 acpi_device_uid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 175         struct acpi_device *acpi_dev = to_acpi_device(dev);
 176
 177         return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
 178 }
 179 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
 180 #endif
 181
 182 static ssize_t
 183 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 184         struct acpi_device *acpi_dev = to_acpi_device(dev);
 185         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 186         int result;
 187
 188         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 189         if (result)
 190                 goto end;
 191
 192         result = sprintf(buf, "%s\n", (char*)path.pointer);
 193         kfree(path.pointer);
 194 end:
 195         return result;
 196 }
 197 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 198
 199 static int acpi_device_setup_files(struct acpi_device *dev)
 200 {
 201         acpi_status status;
 202         acpi_handle temp;
 203         int result = 0;
 204
 205         /*
 206          * Devices gotten from FADT don't have a "path" attribute
 207          */
 208         if (dev->handle) {
 209                 result = device_create_file(&dev->dev, &dev_attr_path);
 210                 if (result)
 211                         goto end;
 212         }
 213
 214         result = device_create_file(&dev->dev, &dev_attr_hid);
 215         if (result)
 216                 goto end;
 217
 218         result = device_create_file(&dev->dev, &dev_attr_modalias);
 219         if (result)
 220                 goto end;
 221
 222 #ifdef CONFIG_PCI_GUESTDEV
 223         if(dev->pnp.unique_id) {
 224                 result = device_create_file(&dev->dev, &dev_attr_uid);
 225                 if(result)
 226                         goto end;
 227         }
 228 #endif
 229         /*
 230          * If device has _EJ0, 'eject' file is created that is used to trigger
 231          * hot-removal function from userland.
 232          */
 233         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 234         if (ACPI_SUCCESS(status))
 235                 result = device_create_file(&dev->dev, &dev_attr_eject);
 236 end:
 237         return result;
 238 }
 239
 240 static void acpi_device_remove_files(struct acpi_device *dev)
 241 {
 242         acpi_status status;
 243         acpi_handle temp;
 244
 245         /*
 246          * If device has _EJ0, 'eject' file is created that is used to trigger
 247          * hot-removal function from userland.
 248          */
 249         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 250         if (ACPI_SUCCESS(status))
 251                 device_remove_file(&dev->dev, &dev_attr_eject);
 252
 253         device_remove_file(&dev->dev, &dev_attr_modalias);
 254         device_remove_file(&dev->dev, &dev_attr_hid);
 255         if (dev->handle)
 256                 device_remove_file(&dev->dev, &dev_attr_path);
 257 }
 258 /* --------------------------------------------------------------------------
 259                         ACPI Bus operations
 260    -------------------------------------------------------------------------- */
 261
 262 int acpi_match_device_ids(struct acpi_device *device,
 263                           const struct acpi_device_id *ids)
 264 {
 265         const struct acpi_device_id *id;
 266         struct acpi_hardware_id *hwid;
 267
 268         /*
 269          * If the device is not present, it is unnecessary to load device
 270          * driver for it.
 271          */
 272         if (!device->status.present)
 273                 return -ENODEV;
 274
 275         for (id = ids; id->id[0]; id++)
 276                 list_for_each_entry(hwid, &device->pnp.ids, list)
 277                         if (!strcmp((char *) id->id, hwid->id))
 278                                 return 0;
 279
 280         return -ENOENT;
 281 }
 282 EXPORT_SYMBOL(acpi_match_device_ids);
 283
 284 static void acpi_free_ids(struct acpi_device *device)
 285 {
 286         struct acpi_hardware_id *id, *tmp;
 287
 288         list_for_each_entry_safe(id, tmp, &device->pnp.ids, list) {
 289                 kfree(id->id);
 290                 kfree(id);
 291         }
 292 #ifdef CONFIG_PCI_GUESTDEV
 293         kfree(device->pnp.unique_id);
 294 #endif
 295 }
 296
 297 static void acpi_device_release(struct device *dev)
 298 {
 299         struct acpi_device *acpi_dev = to_acpi_device(dev);
 300
 301         acpi_free_ids(acpi_dev);
 302         kfree(acpi_dev);
 303 }
 304
 305 static int acpi_device_suspend(struct device *dev, pm_message_t state)
 306 {
 307         struct acpi_device *acpi_dev = to_acpi_device(dev);
 308         struct acpi_driver *acpi_drv = acpi_dev->driver;
 309
 310         if (acpi_drv && acpi_drv->ops.suspend)
 311                 return acpi_drv->ops.suspend(acpi_dev, state);
 312         return 0;
 313 }
 314
 315 static int acpi_device_resume(struct device *dev)
 316 {
 317         struct acpi_device *acpi_dev = to_acpi_device(dev);
 318         struct acpi_driver *acpi_drv = acpi_dev->driver;
 319
 320         if (acpi_drv && acpi_drv->ops.resume)
 321                 return acpi_drv->ops.resume(acpi_dev);
 322         return 0;
 323 }
 324
 325 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 326 {
 327         struct acpi_device *acpi_dev = to_acpi_device(dev);
 328         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 329
 330         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 331 }
 332
 333 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 334 {
 335         struct acpi_device *acpi_dev = to_acpi_device(dev);
 336         int len;
 337
 338         if (add_uevent_var(env, "MODALIAS="))
 339                 return -ENOMEM;
 340         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 341                               sizeof(env->buf) - env->buflen);
 342         if (len >= (sizeof(env->buf) - env->buflen))
 343                 return -ENOMEM;
 344         env->buflen += len;
 345         return 0;
 346 }
 347
 348 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 349 {
 350         struct acpi_device *device = data;
 351
 352         device->driver->ops.notify(device, event);
 353 }
 354
 355 static acpi_status acpi_device_notify_fixed(void *data)
 356 {
 357         struct acpi_device *device = data;
 358
 359         /* Fixed hardware devices have no handles */
 360         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 361         return AE_OK;
 362 }
 363
 364 static int acpi_device_install_notify_handler(struct acpi_device *device)
 365 {
 366         acpi_status status;
 367
 368         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 369                 status =
 370                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 371                                                      acpi_device_notify_fixed,
 372                                                      device);
 373         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 374                 status =
 375                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 376                                                      acpi_device_notify_fixed,
 377                                                      device);
 378         else
 379                 status = acpi_install_notify_handler(device->handle,
 380                                                      ACPI_DEVICE_NOTIFY,
 381                                                      acpi_device_notify,
 382                                                      device);
 383
 384         if (ACPI_FAILURE(status))
 385                 return -EINVAL;
 386         return 0;
 387 }
 388
 389 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 390 {
 391         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 392                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 393                                                 acpi_device_notify_fixed);
 394         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 395                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 396                                                 acpi_device_notify_fixed);
 397         else
 398                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 399                                            acpi_device_notify);
 400 }
 401
 402 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
 403 static int acpi_start_single_object(struct acpi_device *);
 404 static int acpi_device_probe(struct device * dev)
 405 {
 406         struct acpi_device *acpi_dev = to_acpi_device(dev);
 407         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 408         int ret;
 409
 410         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
 411         if (!ret) {
 412                 if (acpi_dev->bus_ops.acpi_op_start)
 413                         acpi_start_single_object(acpi_dev);
 414
 415                 if (acpi_drv->ops.notify) {
 416                         ret = acpi_device_install_notify_handler(acpi_dev);
 417                         if (ret) {
 418                                 if (acpi_drv->ops.remove)
 419                                         acpi_drv->ops.remove(acpi_dev,
 420                                                      acpi_dev->removal_type);
 421                                 return ret;
 422                         }
 423                 }
 424
 425                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 426                         "Found driver [%s] for device [%s]\n",
 427                         acpi_drv->name, acpi_dev->pnp.bus_id));
 428                 get_device(dev);
 429         }
 430         return ret;
 431 }
 432
 433 static int acpi_device_remove(struct device * dev)
 434 {
 435         struct acpi_device *acpi_dev = to_acpi_device(dev);
 436         struct acpi_driver *acpi_drv = acpi_dev->driver;
 437
 438         if (acpi_drv) {
 439                 if (acpi_drv->ops.notify)
 440                         acpi_device_remove_notify_handler(acpi_dev);
 441                 if (acpi_drv->ops.remove)
 442                         acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
 443         }
 444         acpi_dev->driver = NULL;
 445         acpi_dev->driver_data = NULL;
 446
 447         put_device(dev);
 448         return 0;
 449 }
 450
 451 struct bus_type acpi_bus_type = {
 452         .name           = "acpi",
 453         .suspend        = acpi_device_suspend,
 454         .resume         = acpi_device_resume,
 455         .match          = acpi_bus_match,
 456         .probe          = acpi_device_probe,
 457         .remove         = acpi_device_remove,
 458         .uevent         = acpi_device_uevent,
 459 };
 460
 461 static int acpi_device_register(struct acpi_device *device)
 462 {
 463         int result;
 464         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 465         int found = 0;
 466
 467         /*
 468          * Linkage
 469          * -------
 470          * Link this device to its parent and siblings.
 471          */
 472         INIT_LIST_HEAD(&device->children);
 473         INIT_LIST_HEAD(&device->node);
 474         INIT_LIST_HEAD(&device->wakeup_list);
 475
 476         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 477         if (!new_bus_id) {
 478                 printk(KERN_ERR PREFIX "Memory allocation error\n");
 479                 return -ENOMEM;
 480         }
 481
 482         mutex_lock(&acpi_device_lock);
 483         /*
 484          * Find suitable bus_id and instance number in acpi_bus_id_list
 485          * If failed, create one and link it into acpi_bus_id_list
 486          */
 487         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 488                 if (!strcmp(acpi_device_bus_id->bus_id,
 489                             acpi_device_hid(device))) {
 490                         acpi_device_bus_id->instance_no++;
 491                         found = 1;
 492                         kfree(new_bus_id);
 493                         break;
 494                 }
 495         }
 496         if (!found) {
 497                 acpi_device_bus_id = new_bus_id;
 498                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
 499                 acpi_device_bus_id->instance_no = 0;
 500                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 501         }
 502         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 503
 504         if (device->parent)
 505                 list_add_tail(&device->node, &device->parent->children);
 506
 507         if (device->wakeup.flags.valid)
 508                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 509         mutex_unlock(&acpi_device_lock);
 510
 511         if (device->parent)
 512                 device->dev.parent = &device->parent->dev;
 513         device->dev.bus = &acpi_bus_type;
 514         device->dev.release = &acpi_device_release;
 515         result = device_register(&device->dev);
 516         if (result) {
 517                 dev_err(&device->dev, "Error registering device\n");
 518                 goto end;
 519         }
 520
 521         result = acpi_device_setup_files(device);
 522         if (result)
 523                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 524                        dev_name(&device->dev));
 525
 526         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
 527         return 0;
 528 end:
 529         mutex_lock(&acpi_device_lock);
 530         if (device->parent)
 531                 list_del(&device->node);
 532         list_del(&device->wakeup_list);
 533         mutex_unlock(&acpi_device_lock);
 534         return result;
 535 }
 536
 537 static void acpi_device_unregister(struct acpi_device *device, int type)
 538 {
 539         mutex_lock(&acpi_device_lock);
 540         if (device->parent)
 541                 list_del(&device->node);
 542
 543         list_del(&device->wakeup_list);
 544         mutex_unlock(&acpi_device_lock);
 545
 546         acpi_detach_data(device->handle, acpi_bus_data_handler);
 547
 548         acpi_device_remove_files(device);
 549         device_unregister(&device->dev);
 550 }
 551
 552 /* --------------------------------------------------------------------------
 553                                  Driver Management
 554    -------------------------------------------------------------------------- */
 555 /**
 556  * acpi_bus_driver_init - add a device to a driver
 557  * @device: the device to add and initialize
 558  * @driver: driver for the device
 559  *
 560  * Used to initialize a device via its device driver.  Called whenever a
 561  * driver is bound to a device.  Invokes the driver's add() ops.
 562  */
 563 static int
 564 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
 565 {
 566         int result = 0;
 567
 568         if (!device || !driver)
 569                 return -EINVAL;
 570
 571         if (!driver->ops.add)
 572                 return -ENOSYS;
 573
 574         result = driver->ops.add(device);
 575         if (result) {
 576                 device->driver = NULL;
 577                 device->driver_data = NULL;
 578                 return result;
 579         }
 580
 581         device->driver = driver;
 582
 583         /*
 584          * TBD - Configuration Management: Assign resources to device based
 585          * upon possible configuration and currently allocated resources.
 586          */
 587
 588         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 589                           "Driver successfully bound to device\n"));
 590         return 0;
 591 }
 592
 593 static int acpi_start_single_object(struct acpi_device *device)
 594 {
 595         int result = 0;
 596         struct acpi_driver *driver;
 597
 598
 599         if (!(driver = device->driver))
 600                 return 0;
 601
 602         if (driver->ops.start) {
 603                 result = driver->ops.start(device);
 604                 if (result && driver->ops.remove)
 605                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
 606         }
 607
 608         return result;
 609 }
 610
 611 /**
 612  * acpi_bus_register_driver - register a driver with the ACPI bus
 613  * @driver: driver being registered
 614  *
 615  * Registers a driver with the ACPI bus.  Searches the namespace for all
 616  * devices that match the driver's criteria and binds.  Returns zero for
 617  * success or a negative error status for failure.
 618  */
 619 int acpi_bus_register_driver(struct acpi_driver *driver)
 620 {
 621         int ret;
 622
 623         if (acpi_disabled)
 624                 return -ENODEV;
 625         driver->drv.name = driver->name;
 626         driver->drv.bus = &acpi_bus_type;
 627         driver->drv.owner = driver->owner;
 628
 629         ret = driver_register(&driver->drv);
 630         return ret;
 631 }
 632
 633 EXPORT_SYMBOL(acpi_bus_register_driver);
 634
 635 /**
 636  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
 637  * @driver: driver to unregister
 638  *
 639  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
 640  * devices that match the driver's criteria and unbinds.
 641  */
 642 void acpi_bus_unregister_driver(struct acpi_driver *driver)
 643 {
 644         driver_unregister(&driver->drv);
 645 }
 646
 647 EXPORT_SYMBOL(acpi_bus_unregister_driver);
 648
 649 /* --------------------------------------------------------------------------
 650                                  Device Enumeration
 651    -------------------------------------------------------------------------- */
 652 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
 653 {
 654         acpi_status status;
 655         int ret;
 656         struct acpi_device *device;
 657
 658         /*
 659          * Fixed hardware devices do not appear in the namespace and do not
 660          * have handles, but we fabricate acpi_devices for them, so we have
 661          * to deal with them specially.
 662          */
 663         if (handle == NULL)
 664                 return acpi_root;
 665
 666         do {
 667                 status = acpi_get_parent(handle, &handle);
 668                 if (status == AE_NULL_ENTRY)
 669                         return NULL;
 670                 if (ACPI_FAILURE(status))
 671                         return acpi_root;
 672
 673                 ret = acpi_bus_get_device(handle, &device);
 674                 if (ret == 0)
 675                         return device;
 676         } while (1);
 677 }
 678
 679 acpi_status
 680 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 681 {
 682         acpi_status status;
 683         acpi_handle tmp;
 684         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 685         union acpi_object *obj;
 686
 687         status = acpi_get_handle(handle, "_EJD", &tmp);
 688         if (ACPI_FAILURE(status))
 689                 return status;
 690
 691         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 692         if (ACPI_SUCCESS(status)) {
 693                 obj = buffer.pointer;
 694                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 695                                          ejd);
 696                 kfree(buffer.pointer);
 697         }
 698         return status;
 699 }
 700 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 701
 702 void acpi_bus_data_handler(acpi_handle handle, void *context)
 703 {
 704
 705         /* TBD */
 706
 707         return;
 708 }
 709
 710 static int acpi_bus_get_perf_flags(struct acpi_device *device)
 711 {
 712         device->performance.state = ACPI_STATE_UNKNOWN;
 713         return 0;
 714 }
 715
 716 static acpi_status
 717 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
 718                                              union acpi_object *package)
 719 {
 720         int i = 0;
 721         union acpi_object *element = NULL;
 722
 723         if (!device || !package || (package->package.count < 2))
 724                 return AE_BAD_PARAMETER;
 725
 726         element = &(package->package.elements[0]);
 727         if (!element)
 728                 return AE_BAD_PARAMETER;
 729         if (element->type == ACPI_TYPE_PACKAGE) {
 730                 if ((element->package.count < 2) ||
 731                     (element->package.elements[0].type !=
 732                      ACPI_TYPE_LOCAL_REFERENCE)
 733                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 734                         return AE_BAD_DATA;
 735                 device->wakeup.gpe_device =
 736                     element->package.elements[0].reference.handle;
 737                 device->wakeup.gpe_number =
 738                     (u32) element->package.elements[1].integer.value;
 739         } else if (element->type == ACPI_TYPE_INTEGER) {
 740                 device->wakeup.gpe_number = element->integer.value;
 741         } else
 742                 return AE_BAD_DATA;
 743
 744         element = &(package->package.elements[1]);
 745         if (element->type != ACPI_TYPE_INTEGER) {
 746                 return AE_BAD_DATA;
 747         }
 748         device->wakeup.sleep_state = element->integer.value;
 749
 750         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
 751                 return AE_NO_MEMORY;
 752         }
 753         device->wakeup.resources.count = package->package.count - 2;
 754         for (i = 0; i < device->wakeup.resources.count; i++) {
 755                 element = &(package->package.elements[i + 2]);
 756                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
 757                         return AE_BAD_DATA;
 758
 759                 device->wakeup.resources.handles[i] = element->reference.handle;
 760         }
 761
 762         return AE_OK;
 763 }
 764
 765 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
 766 {
 767         struct acpi_device_id button_device_ids[] = {
 768                 {"PNP0C0D", 0},
 769                 {"PNP0C0C", 0},
 770                 {"PNP0C0E", 0},
 771                 {"", 0},
 772         };
 773         acpi_status status;
 774         acpi_event_status event_status;
 775
 776         device->wakeup.run_wake_count = 0;
 777         device->wakeup.flags.notifier_present = 0;
 778
 779         /* Power button, Lid switch always enable wakeup */
 780         if (!acpi_match_device_ids(device, button_device_ids)) {
 781                 device->wakeup.flags.run_wake = 1;
 782                 device->wakeup.flags.always_enabled = 1;
 783                 return;
 784         }
 785
 786         status = acpi_get_gpe_status(NULL, device->wakeup.gpe_number,
 787                                         ACPI_NOT_ISR, &event_status);
 788         if (status == AE_OK)
 789                 device->wakeup.flags.run_wake =
 790                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
 791 }
 792
 793 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 794 {
 795         acpi_status status = 0;
 796         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 797         union acpi_object *package = NULL;
 798         int psw_error;
 799
 800         /* _PRW */
 801         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
 802         if (ACPI_FAILURE(status)) {
 803                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 804                 goto end;
 805         }
 806
 807         package = (union acpi_object *)buffer.pointer;
 808         status = acpi_bus_extract_wakeup_device_power_package(device, package);
 809         if (ACPI_FAILURE(status)) {
 810                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
 811                 goto end;
 812         }
 813
 814         kfree(buffer.pointer);
 815
 816         device->wakeup.flags.valid = 1;
 817         device->wakeup.prepare_count = 0;
 818         acpi_bus_set_run_wake_flags(device);
 819         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
 820          * system for the ACPI device with the _PRW object.
 821          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 822          * So it is necessary to call _DSW object first. Only when it is not
 823          * present will the _PSW object used.
 824          */
 825         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
 826         if (psw_error)
 827                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 828                                 "error in _DSW or _PSW evaluation\n"));
 829
 830 end:
 831         if (ACPI_FAILURE(status))
 832                 device->flags.wake_capable = 0;
 833         return 0;
 834 }
 835
 836 static int acpi_bus_get_power_flags(struct acpi_device *device)
 837 {
 838         acpi_status status = 0;
 839         acpi_handle handle = NULL;
 840         u32 i = 0;
 841
 842
 843         /*
 844          * Power Management Flags
 845          */
 846         status = acpi_get_handle(device->handle, "_PSC", &handle);
 847         if (ACPI_SUCCESS(status))
 848                 device->power.flags.explicit_get = 1;
 849         status = acpi_get_handle(device->handle, "_IRC", &handle);
 850         if (ACPI_SUCCESS(status))
 851                 device->power.flags.inrush_current = 1;
 852
 853         /*
 854          * Enumerate supported power management states
 855          */
 856         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
 857                 struct acpi_device_power_state *ps = &device->power.states[i];
 858                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
 859
 860                 /* Evaluate "_PRx" to se if power resources are referenced */
 861                 acpi_evaluate_reference(device->handle, object_name, NULL,
 862                                         &ps->resources);
 863                 if (ps->resources.count) {
 864                         device->power.flags.power_resources = 1;
 865                         ps->flags.valid = 1;
 866                 }
 867
 868                 /* Evaluate "_PSx" to see if we can do explicit sets */
 869                 object_name[2] = 'S';
 870                 status = acpi_get_handle(device->handle, object_name, &handle);
 871                 if (ACPI_SUCCESS(status)) {
 872                         ps->flags.explicit_set = 1;
 873                         ps->flags.valid = 1;
 874                 }
 875
 876                 /* State is valid if we have some power control */
 877                 if (ps->resources.count || ps->flags.explicit_set)
 878                         ps->flags.valid = 1;
 879
 880                 ps->power = -1; /* Unknown - driver assigned */
 881                 ps->latency = -1;       /* Unknown - driver assigned */
 882         }
 883
 884         /* Set defaults for D0 and D3 states (always valid) */
 885         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 886         device->power.states[ACPI_STATE_D0].power = 100;
 887         device->power.states[ACPI_STATE_D3].flags.valid = 1;
 888         device->power.states[ACPI_STATE_D3].power = 0;
 889
 890         /* TBD: System wake support and resource requirements. */
 891
 892         device->power.state = ACPI_STATE_UNKNOWN;
 893         acpi_bus_get_power(device->handle, &(device->power.state));
 894
 895         return 0;
 896 }
 897
 898 static int acpi_bus_get_flags(struct acpi_device *device)
 899 {
 900         acpi_status status = AE_OK;
 901         acpi_handle temp = NULL;
 902
 903
 904         /* Presence of _STA indicates 'dynamic_status' */
 905         status = acpi_get_handle(device->handle, "_STA", &temp);
 906         if (ACPI_SUCCESS(status))
 907                 device->flags.dynamic_status = 1;
 908
 909         /* Presence of _RMV indicates 'removable' */
 910         status = acpi_get_handle(device->handle, "_RMV", &temp);
 911         if (ACPI_SUCCESS(status))
 912                 device->flags.removable = 1;
 913
 914         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 915         status = acpi_get_handle(device->handle, "_EJD", &temp);
 916         if (ACPI_SUCCESS(status))
 917                 device->flags.ejectable = 1;
 918         else {
 919                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
 920                 if (ACPI_SUCCESS(status))
 921                         device->flags.ejectable = 1;
 922         }
 923
 924         /* Presence of _LCK indicates 'lockable' */
 925         status = acpi_get_handle(device->handle, "_LCK", &temp);
 926         if (ACPI_SUCCESS(status))
 927                 device->flags.lockable = 1;
 928
 929         /* Presence of _PS0|_PR0 indicates 'power manageable' */
 930         status = acpi_get_handle(device->handle, "_PS0", &temp);
 931         if (ACPI_FAILURE(status))
 932                 status = acpi_get_handle(device->handle, "_PR0", &temp);
 933         if (ACPI_SUCCESS(status))
 934                 device->flags.power_manageable = 1;
 935
 936         /* Presence of _PRW indicates wake capable */
 937         status = acpi_get_handle(device->handle, "_PRW", &temp);
 938         if (ACPI_SUCCESS(status))
 939                 device->flags.wake_capable = 1;
 940
 941         /* TBD: Performance management */
 942
 943         return 0;
 944 }
 945
 946 static void acpi_device_get_busid(struct acpi_device *device)
 947 {
 948         char bus_id[5] = { '?', 0 };
 949         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
 950         int i = 0;
 951
 952         /*
 953          * Bus ID
 954          * ------
 955          * The device's Bus ID is simply the object name.
 956          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
 957          */
 958         if (ACPI_IS_ROOT_DEVICE(device)) {
 959                 strcpy(device->pnp.bus_id, "ACPI");
 960                 return;
 961         }
 962
 963         switch (device->device_type) {
 964         case ACPI_BUS_TYPE_POWER_BUTTON:
 965                 strcpy(device->pnp.bus_id, "PWRF");
 966                 break;
 967         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 968                 strcpy(device->pnp.bus_id, "SLPF");
 969                 break;
 970         default:
 971                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
 972                 /* Clean up trailing underscores (if any) */
 973                 for (i = 3; i > 1; i--) {
 974                         if (bus_id[i] == '_')
 975                                 bus_id[i] = '\0';
 976                         else
 977                                 break;
 978                 }
 979                 strcpy(device->pnp.bus_id, bus_id);
 980                 break;
 981         }
 982 }
 983
 984 /*
 985  * acpi_bay_match - see if a device is an ejectable driver bay
 986  *
 987  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
 988  * then we can safely call it an ejectable drive bay
 989  */
 990 static int acpi_bay_match(struct acpi_device *device){
 991         acpi_status status;
 992         acpi_handle handle;
 993         acpi_handle tmp;
 994         acpi_handle phandle;
 995
 996         handle = device->handle;
 997
 998         status = acpi_get_handle(handle, "_EJ0", &tmp);
 999         if (ACPI_FAILURE(status))
1000                 return -ENODEV;
1001
1002         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
1003                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
1004                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
1005                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
1006                 return 0;
1007
1008         if (acpi_get_parent(handle, &phandle))
1009                 return -ENODEV;
1010
1011         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
1012                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
1013                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
1014                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
1015                 return 0;
1016
1017         return -ENODEV;
1018 }
1019
1020 /*
1021  * acpi_dock_match - see if a device has a _DCK method
1022  */
1023 static int acpi_dock_match(struct acpi_device *device)
1024 {
1025         acpi_handle tmp;
1026         return acpi_get_handle(device->handle, "_DCK", &tmp);
1027 }
1028
1029 char *acpi_device_hid(struct acpi_device *device)
1030 {
1031         struct acpi_hardware_id *hid;
1032
1033         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1034         return hid->id;
1035 }
1036 EXPORT_SYMBOL(acpi_device_hid);
1037
1038 static void acpi_add_id(struct acpi_device *device, const char *dev_id)
1039 {
1040         struct acpi_hardware_id *id;
1041
1042         id = kmalloc(sizeof(*id), GFP_KERNEL);
1043         if (!id)
1044                 return;
1045
1046         id->id = kmalloc(strlen(dev_id) + 1, GFP_KERNEL);
1047         if (!id->id) {
1048                 kfree(id);
1049                 return;
1050         }
1051
1052         strcpy(id->id, dev_id);
1053         list_add_tail(&id->list, &device->pnp.ids);
1054 }
1055
1056 /*
1057  * Old IBM workstations have a DSDT bug wherein the SMBus object
1058  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1059  * prefix.  Work around this.
1060  */
1061 static int acpi_ibm_smbus_match(struct acpi_device *device)
1062 {
1063         acpi_handle h_dummy;
1064         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1065         int result;
1066
1067         if (!dmi_name_in_vendors("IBM"))
1068                 return -ENODEV;
1069
1070         /* Look for SMBS object */
1071         result = acpi_get_name(device->handle, ACPI_SINGLE_NAME, &path);
1072         if (result)
1073                 return result;
1074
1075         if (strcmp("SMBS", path.pointer)) {
1076                 result = -ENODEV;
1077                 goto out;
1078         }
1079
1080         /* Does it have the necessary (but misnamed) methods? */
1081         result = -ENODEV;
1082         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "SBI", &h_dummy)) &&
1083             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBR", &h_dummy)) &&
1084             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBW", &h_dummy)))
1085                 result = 0;
1086 out:
1087         kfree(path.pointer);
1088         return result;
1089 }
1090
1091 static void acpi_device_set_id(struct acpi_device *device)
1092 {
1093         acpi_status status;
1094         struct acpi_device_info *info;
1095         struct acpica_device_id_list *cid_list;
1096         int i;
1097
1098         switch (device->device_type) {
1099         case ACPI_BUS_TYPE_DEVICE:
1100                 if (ACPI_IS_ROOT_DEVICE(device)) {
1101                         acpi_add_id(device, ACPI_SYSTEM_HID);
1102                         break;
1103                 } else if (ACPI_IS_ROOT_DEVICE(device->parent)) {
1104                         /* \_SB_, the only root-level namespace device */
1105                         acpi_add_id(device, ACPI_BUS_HID);
1106                         strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1107                         strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1108                         break;
1109                 }
1110
1111                 status = acpi_get_object_info(device->handle, &info);
1112                 if (ACPI_FAILURE(status)) {
1113                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1114                         return;
1115                 }
1116
1117                 if (info->valid & ACPI_VALID_HID)
1118                         acpi_add_id(device, info->hardware_id.string);
1119                 if (info->valid & ACPI_VALID_CID) {
1120                         cid_list = &info->compatible_id_list;
1121                         for (i = 0; i < cid_list->count; i++)
1122                                 acpi_add_id(device, cid_list->ids[i].string);
1123                 }
1124 #ifdef CONFIG_PCI_GUESTDEV
1125                 if (info->valid & ACPI_VALID_UID)
1126                         device->pnp.unique_id = kstrdup(info->unique_id.string,
1127                                                         GFP_KERNEL);
1128 #endif
1129                 if (info->valid & ACPI_VALID_ADR) {
1130                         device->pnp.bus_address = info->address;
1131                         device->flags.bus_address = 1;
1132                 }
1133
1134                 kfree(info);
1135
1136                 /*
1137                  * Some devices don't reliably have _HIDs & _CIDs, so add
1138                  * synthetic HIDs to make sure drivers can find them.
1139                  */
1140                 if (acpi_is_video_device(device))
1141                         acpi_add_id(device, ACPI_VIDEO_HID);
1142                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1143                         acpi_add_id(device, ACPI_BAY_HID);
1144                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1145                         acpi_add_id(device, ACPI_DOCK_HID);
1146                 else if (!acpi_ibm_smbus_match(device))
1147                         acpi_add_id(device, ACPI_SMBUS_IBM_HID);
1148
1149                 break;
1150         case ACPI_BUS_TYPE_POWER:
1151                 acpi_add_id(device, ACPI_POWER_HID);
1152                 break;
1153         case ACPI_BUS_TYPE_PROCESSOR:
1154                 acpi_add_id(device, ACPI_PROCESSOR_OBJECT_HID);
1155                 break;
1156         case ACPI_BUS_TYPE_THERMAL:
1157                 acpi_add_id(device, ACPI_THERMAL_HID);
1158                 break;
1159         case ACPI_BUS_TYPE_POWER_BUTTON:
1160                 acpi_add_id(device, ACPI_BUTTON_HID_POWERF);
1161                 break;
1162         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1163                 acpi_add_id(device, ACPI_BUTTON_HID_SLEEPF);
1164                 break;
1165         }
1166
1167         /*
1168          * We build acpi_devices for some objects that don't have _HID or _CID,
1169          * e.g., PCI bridges and slots.  Drivers can't bind to these objects,
1170          * but we do use them indirectly by traversing the acpi_device tree.
1171          * This generic ID isn't useful for driver binding, but it provides
1172          * the useful property that "every acpi_device has an ID."
1173          */
1174         if (list_empty(&device->pnp.ids))
1175                 acpi_add_id(device, "device");
1176 }
1177
1178 static int acpi_device_set_context(struct acpi_device *device)
1179 {
1180         acpi_status status;
1181
1182         /*
1183          * Context
1184          * -------
1185          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1186          * resolutions from handle->device very efficient.  Fixed hardware
1187          * devices have no handles, so we skip them.
1188          */
1189         if (!device->handle)
1190                 return 0;
1191
1192         status = acpi_attach_data(device->handle,
1193                                   acpi_bus_data_handler, device);
1194         if (ACPI_SUCCESS(status))
1195                 return 0;
1196
1197         printk(KERN_ERR PREFIX "Error attaching device data\n");
1198         return -ENODEV;
1199 }
1200
1201 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1202 {
1203         if (!dev)
1204                 return -EINVAL;
1205
1206         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1207         device_release_driver(&dev->dev);
1208
1209         if (!rmdevice)
1210                 return 0;
1211
1212         /*
1213          * unbind _ADR-Based Devices when hot removal
1214          */
1215         if (dev->flags.bus_address) {
1216                 if ((dev->parent) && (dev->parent->ops.unbind))
1217                         dev->parent->ops.unbind(dev);
1218         }
1219         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1220
1221         return 0;
1222 }
1223
1224 static int acpi_add_single_object(struct acpi_device **child,
1225                                   acpi_handle handle, int type,
1226                                   unsigned long long sta,
1227                                   struct acpi_bus_ops *ops)
1228 {
1229         int result;
1230         struct acpi_device *device;
1231         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1232
1233         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1234         if (!device) {
1235                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1236                 return -ENOMEM;
1237         }
1238
1239         INIT_LIST_HEAD(&device->pnp.ids);
1240         device->device_type = type;
1241         device->handle = handle;
1242         device->parent = acpi_bus_get_parent(handle);
1243         device->bus_ops = *ops; /* workround for not call .start */
1244         STRUCT_TO_INT(device->status) = sta;
1245
1246         acpi_device_get_busid(device);
1247
1248         /*
1249          * Flags
1250          * -----
1251          * Note that we only look for object handles -- cannot evaluate objects
1252          * until we know the device is present and properly initialized.
1253          */
1254         result = acpi_bus_get_flags(device);
1255         if (result)
1256                 goto end;
1257
1258         /*
1259          * Initialize Device
1260          * -----------------
1261          * TBD: Synch with Core's enumeration/initialization process.
1262          */
1263         acpi_device_set_id(device);
1264
1265         /*
1266          * Power Management
1267          * ----------------
1268          */
1269         if (device->flags.power_manageable) {
1270                 result = acpi_bus_get_power_flags(device);
1271                 if (result)
1272                         goto end;
1273         }
1274
1275         /*
1276          * Wakeup device management
1277          *-----------------------
1278          */
1279         if (device->flags.wake_capable) {
1280                 result = acpi_bus_get_wakeup_device_flags(device);
1281                 if (result)
1282                         goto end;
1283         }
1284
1285         /*
1286          * Performance Management
1287          * ----------------------
1288          */
1289         if (device->flags.performance_manageable) {
1290                 result = acpi_bus_get_perf_flags(device);
1291                 if (result)
1292                         goto end;
1293         }
1294
1295         if ((result = acpi_device_set_context(device)))
1296                 goto end;
1297
1298         result = acpi_device_register(device);
1299
1300         /*
1301          * Bind _ADR-Based Devices when hot add
1302          */
1303         if (device->flags.bus_address) {
1304                 if (device->parent && device->parent->ops.bind)
1305                         device->parent->ops.bind(device);
1306         }
1307
1308 end:
1309         if (!result) {
1310                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1311                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1312                         "Adding %s [%s] parent %s\n", dev_name(&device->dev),
1313                          (char *) buffer.pointer,
1314                          device->parent ? dev_name(&device->parent->dev) :
1315                                           "(null)"));
1316                 kfree(buffer.pointer);
1317                 *child = device;
1318         } else
1319                 acpi_device_release(&device->dev);
1320
1321         return result;
1322 }
1323
1324 #define ACPI_STA_DEFAULT (ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED | \
1325                           ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING)
1326
1327 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1328                                     unsigned long long *sta)
1329 {
1330         acpi_status status;
1331         acpi_object_type acpi_type;
1332
1333         status = acpi_get_type(handle, &acpi_type);
1334         if (ACPI_FAILURE(status))
1335                 return -ENODEV;
1336
1337         switch (acpi_type) {
1338         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1339         case ACPI_TYPE_DEVICE:
1340                 *type = ACPI_BUS_TYPE_DEVICE;
1341                 status = acpi_bus_get_status_handle(handle, sta);
1342                 if (ACPI_FAILURE(status))
1343                         return -ENODEV;
1344                 break;
1345         case ACPI_TYPE_PROCESSOR:
1346                 *type = ACPI_BUS_TYPE_PROCESSOR;
1347                 status = acpi_bus_get_status_handle(handle, sta);
1348                 if (ACPI_FAILURE(status))
1349                         return -ENODEV;
1350                 break;
1351         case ACPI_TYPE_THERMAL:
1352                 *type = ACPI_BUS_TYPE_THERMAL;
1353                 *sta = ACPI_STA_DEFAULT;
1354                 break;
1355         case ACPI_TYPE_POWER:
1356                 *type = ACPI_BUS_TYPE_POWER;
1357                 *sta = ACPI_STA_DEFAULT;
1358                 break;
1359         default:
1360                 return -ENODEV;
1361         }
1362
1363         return 0;
1364 }
1365
1366 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl,
1367                                       void *context, void **return_value)
1368 {
1369         struct acpi_bus_ops *ops = context;
1370         int type;
1371         unsigned long long sta;
1372         struct acpi_device *device;
1373         acpi_status status;
1374         int result;
1375
1376         result = acpi_bus_type_and_status(handle, &type, &sta);
1377         if (result)
1378                 return AE_OK;
1379
1380         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1381             !(sta & ACPI_STA_DEVICE_FUNCTIONING))
1382                 return AE_CTRL_DEPTH;
1383
1384         /*
1385          * We may already have an acpi_device from a previous enumeration.  If
1386          * so, we needn't add it again, but we may still have to start it.
1387          */
1388         device = NULL;
1389         acpi_bus_get_device(handle, &device);
1390         if (ops->acpi_op_add && !device)
1391                 acpi_add_single_object(&device, handle, type, sta, ops);
1392
1393         if (!device)
1394                 return AE_CTRL_DEPTH;
1395
1396         if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1397                 status = acpi_start_single_object(device);
1398                 if (ACPI_FAILURE(status))
1399                         return AE_CTRL_DEPTH;
1400         }
1401
1402         if (!*return_value)
1403                 *return_value = device;
1404         return AE_OK;
1405 }
1406
1407 static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops,
1408                          struct acpi_device **child)
1409 {
1410         acpi_status status;
1411         void *device = NULL;
1412
1413         status = acpi_bus_check_add(handle, 0, ops, &device);
1414         if (ACPI_SUCCESS(status))
1415                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1416                                     acpi_bus_check_add, NULL, ops, &device);
1417
1418         if (child)
1419                 *child = device;
1420
1421         if (device)
1422                 return 0;
1423         else
1424                 return -ENODEV;
1425 }
1426
1427 /*
1428  * acpi_bus_add and acpi_bus_start
1429  *
1430  * scan a given ACPI tree and (probably recently hot-plugged)
1431  * create and add or starts found devices.
1432  *
1433  * If no devices were found -ENODEV is returned which does not
1434  * mean that this is a real error, there just have been no suitable
1435  * ACPI objects in the table trunk from which the kernel could create
1436  * a device and add/start an appropriate driver.
1437  */
1438
1439 int
1440 acpi_bus_add(struct acpi_device **child,
1441              struct acpi_device *parent, acpi_handle handle, int type)
1442 {
1443         struct acpi_bus_ops ops;
1444
1445         memset(&ops, 0, sizeof(ops));
1446         ops.acpi_op_add = 1;
1447
1448         return acpi_bus_scan(handle, &ops, child);
1449 }
1450 EXPORT_SYMBOL(acpi_bus_add);
1451
1452 int acpi_bus_start(struct acpi_device *device)
1453 {
1454         struct acpi_bus_ops ops;
1455
1456         if (!device)
1457                 return -EINVAL;
1458
1459         memset(&ops, 0, sizeof(ops));
1460         ops.acpi_op_start = 1;
1461
1462         return acpi_bus_scan(device->handle, &ops, NULL);
1463 }
1464 EXPORT_SYMBOL(acpi_bus_start);
1465
1466 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1467 {
1468         acpi_status status;
1469         struct acpi_device *parent, *child;
1470         acpi_handle phandle, chandle;
1471         acpi_object_type type;
1472         u32 level = 1;
1473         int err = 0;
1474
1475         parent = start;
1476         phandle = start->handle;
1477         child = chandle = NULL;
1478
1479         while ((level > 0) && parent && (!err)) {
1480                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1481                                               chandle, &chandle);
1482
1483                 /*
1484                  * If this scope is exhausted then move our way back up.
1485                  */
1486                 if (ACPI_FAILURE(status)) {
1487                         level--;
1488                         chandle = phandle;
1489                         acpi_get_parent(phandle, &phandle);
1490                         child = parent;
1491                         parent = parent->parent;
1492
1493                         if (level == 0)
1494                                 err = acpi_bus_remove(child, rmdevice);
1495                         else
1496                                 err = acpi_bus_remove(child, 1);
1497
1498                         continue;
1499                 }
1500
1501                 status = acpi_get_type(chandle, &type);
1502                 if (ACPI_FAILURE(status)) {
1503                         continue;
1504                 }
1505                 /*
1506                  * If there is a device corresponding to chandle then
1507                  * parse it (depth-first).
1508                  */
1509                 if (acpi_bus_get_device(chandle, &child) == 0) {
1510                         level++;
1511                         phandle = chandle;
1512                         chandle = NULL;
1513                         parent = child;
1514                 }
1515                 continue;
1516         }
1517         return err;
1518 }
1519 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1520
1521 static int acpi_bus_scan_fixed(void)
1522 {
1523         int result = 0;
1524         struct acpi_device *device = NULL;
1525         struct acpi_bus_ops ops;
1526
1527         memset(&ops, 0, sizeof(ops));
1528         ops.acpi_op_add = 1;
1529         ops.acpi_op_start = 1;
1530
1531         /*
1532          * Enumerate all fixed-feature devices.
1533          */
1534         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1535                 result = acpi_add_single_object(&device, NULL,
1536                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1537                                                 ACPI_STA_DEFAULT,
1538                                                 &ops);
1539         }
1540
1541         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1542                 result = acpi_add_single_object(&device, NULL,
1543                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1544                                                 ACPI_STA_DEFAULT,
1545                                                 &ops);
1546         }
1547
1548         return result;
1549 }
1550
1551 int __init acpi_scan_init(void)
1552 {
1553         int result;
1554         struct acpi_bus_ops ops;
1555
1556         memset(&ops, 0, sizeof(ops));
1557         ops.acpi_op_add = 1;
1558         ops.acpi_op_start = 1;
1559
1560         result = bus_register(&acpi_bus_type);
1561         if (result) {
1562                 /* We don't want to quit even if we failed to add suspend/resume */
1563                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1564         }
1565
1566         /*
1567          * Enumerate devices in the ACPI namespace.
1568          */
1569         result = acpi_bus_scan(ACPI_ROOT_OBJECT, &ops, &acpi_root);
1570
1571         if (!result)
1572                 result = acpi_bus_scan_fixed();
1573
1574         if (result)
1575                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1576
1577         return result;
1578 }