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