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 #ifdef CONFIG_PCI_GUESTDEV
 174 static ssize_t
 175 acpi_device_uid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 176         struct acpi_device *acpi_dev = to_acpi_device(dev);
 177
 178         return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
 179 }
 180 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
 181 #endif
 182
 183 static ssize_t
 184 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 185         struct acpi_device *acpi_dev = to_acpi_device(dev);
 186         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 187         int result;
 188
 189         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 190         if (result)
 191                 goto end;
 192
 193         result = sprintf(buf, "%s\n", (char*)path.pointer);
 194         kfree(path.pointer);
 195 end:
 196         return result;
 197 }
 198 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 199
 200 static int acpi_device_setup_files(struct acpi_device *dev)
 201 {
 202         acpi_status status;
 203         acpi_handle temp;
 204         int result = 0;
 205
 206         /*
 207          * Devices gotten from FADT don't have a "path" attribute
 208          */
 209         if (dev->handle) {
 210                 result = device_create_file(&dev->dev, &dev_attr_path);
 211                 if (result)
 212                         goto end;
 213         }
 214
 215         result = device_create_file(&dev->dev, &dev_attr_hid);
 216         if (result)
 217                 goto end;
 218
 219         result = device_create_file(&dev->dev, &dev_attr_modalias);
 220         if (result)
 221                 goto end;
 222
 223 #ifdef CONFIG_PCI_GUESTDEV
 224         if(dev->pnp.unique_id) {
 225                 result = device_create_file(&dev->dev, &dev_attr_uid);
 226                 if(result)
 227                         goto end;
 228         }
 229 #endif
 230         /*
 231          * If device has _EJ0, 'eject' file is created that is used to trigger
 232          * hot-removal function from userland.
 233          */
 234         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 235         if (ACPI_SUCCESS(status))
 236                 result = device_create_file(&dev->dev, &dev_attr_eject);
 237 end:
 238         return result;
 239 }
 240
 241 static void acpi_device_remove_files(struct acpi_device *dev)
 242 {
 243         acpi_status status;
 244         acpi_handle temp;
 245
 246         /*
 247          * If device has _EJ0, 'eject' file is created that is used to trigger
 248          * hot-removal function from userland.
 249          */
 250         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 251         if (ACPI_SUCCESS(status))
 252                 device_remove_file(&dev->dev, &dev_attr_eject);
 253
 254         device_remove_file(&dev->dev, &dev_attr_modalias);
 255         device_remove_file(&dev->dev, &dev_attr_hid);
 256         if (dev->handle)
 257                 device_remove_file(&dev->dev, &dev_attr_path);
 258 }
 259 /* --------------------------------------------------------------------------
 260                         ACPI Bus operations
 261    -------------------------------------------------------------------------- */
 262
 263 int acpi_match_device_ids(struct acpi_device *device,
 264                           const struct acpi_device_id *ids)
 265 {
 266         const struct acpi_device_id *id;
 267         struct acpi_hardware_id *hwid;
 268
 269         /*
 270          * If the device is not present, it is unnecessary to load device
 271          * driver for it.
 272          */
 273         if (!device->status.present)
 274                 return -ENODEV;
 275
 276         for (id = ids; id->id[0]; id++)
 277                 list_for_each_entry(hwid, &device->pnp.ids, list)
 278                         if (!strcmp((char *) id->id, hwid->id))
 279                                 return 0;
 280
 281         return -ENOENT;
 282 }
 283 EXPORT_SYMBOL(acpi_match_device_ids);
 284
 285 static void acpi_free_ids(struct acpi_device *device)
 286 {
 287         struct acpi_hardware_id *id, *tmp;
 288
 289         list_for_each_entry_safe(id, tmp, &device->pnp.ids, list) {
 290                 kfree(id->id);
 291                 kfree(id);
 292         }
 293 #ifdef CONFIG_PCI_GUESTDEV
 294         kfree(device->pnp.unique_id);
 295 #endif
 296 }
 297
 298 static void acpi_device_release(struct device *dev)
 299 {
 300         struct acpi_device *acpi_dev = to_acpi_device(dev);
 301
 302         acpi_free_ids(acpi_dev);
 303         kfree(acpi_dev);
 304 }
 305
 306 static int acpi_device_suspend(struct device *dev, pm_message_t state)
 307 {
 308         struct acpi_device *acpi_dev = to_acpi_device(dev);
 309         struct acpi_driver *acpi_drv = acpi_dev->driver;
 310
 311         if (acpi_drv && acpi_drv->ops.suspend)
 312                 return acpi_drv->ops.suspend(acpi_dev, state);
 313         return 0;
 314 }
 315
 316 static int acpi_device_resume(struct device *dev)
 317 {
 318         struct acpi_device *acpi_dev = to_acpi_device(dev);
 319         struct acpi_driver *acpi_drv = acpi_dev->driver;
 320
 321         if (acpi_drv && acpi_drv->ops.resume)
 322                 return acpi_drv->ops.resume(acpi_dev);
 323         return 0;
 324 }
 325
 326 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 327 {
 328         struct acpi_device *acpi_dev = to_acpi_device(dev);
 329         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 330
 331         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 332 }
 333
 334 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 335 {
 336         struct acpi_device *acpi_dev = to_acpi_device(dev);
 337         int len;
 338
 339         if (add_uevent_var(env, "MODALIAS="))
 340                 return -ENOMEM;
 341         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 342                               sizeof(env->buf) - env->buflen);
 343         if (len >= (sizeof(env->buf) - env->buflen))
 344                 return -ENOMEM;
 345         env->buflen += len;
 346         return 0;
 347 }
 348
 349 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 350 {
 351         struct acpi_device *device = data;
 352
 353         device->driver->ops.notify(device, event);
 354 }
 355
 356 static acpi_status acpi_device_notify_fixed(void *data)
 357 {
 358         struct acpi_device *device = data;
 359
 360         /* Fixed hardware devices have no handles */
 361         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 362         return AE_OK;
 363 }
 364
 365 static int acpi_device_install_notify_handler(struct acpi_device *device)
 366 {
 367         acpi_status status;
 368
 369         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 370                 status =
 371                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 372                                                      acpi_device_notify_fixed,
 373                                                      device);
 374         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 375                 status =
 376                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 377                                                      acpi_device_notify_fixed,
 378                                                      device);
 379         else
 380                 status = acpi_install_notify_handler(device->handle,
 381                                                      ACPI_DEVICE_NOTIFY,
 382                                                      acpi_device_notify,
 383                                                      device);
 384
 385         if (ACPI_FAILURE(status))
 386                 return -EINVAL;
 387         return 0;
 388 }
 389
 390 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 391 {
 392         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 393                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 394                                                 acpi_device_notify_fixed);
 395         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 396                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 397                                                 acpi_device_notify_fixed);
 398         else
 399                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 400                                            acpi_device_notify);
 401 }
 402
 403 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
 404 static int acpi_start_single_object(struct acpi_device *);
 405 static int acpi_device_probe(struct device * dev)
 406 {
 407         struct acpi_device *acpi_dev = to_acpi_device(dev);
 408         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 409         int ret;
 410
 411         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
 412         if (!ret) {
 413                 if (acpi_dev->bus_ops.acpi_op_start)
 414                         acpi_start_single_object(acpi_dev);
 415
 416                 if (acpi_drv->ops.notify) {
 417                         ret = acpi_device_install_notify_handler(acpi_dev);
 418                         if (ret) {
 419                                 if (acpi_drv->ops.remove)
 420                                         acpi_drv->ops.remove(acpi_dev,
 421                                                      acpi_dev->removal_type);
 422                                 return ret;
 423                         }
 424                 }
 425
 426                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 427                         "Found driver [%s] for device [%s]\n",
 428                         acpi_drv->name, acpi_dev->pnp.bus_id));
 429                 get_device(dev);
 430         }
 431         return ret;
 432 }
 433
 434 static int acpi_device_remove(struct device * dev)
 435 {
 436         struct acpi_device *acpi_dev = to_acpi_device(dev);
 437         struct acpi_driver *acpi_drv = acpi_dev->driver;
 438
 439         if (acpi_drv) {
 440                 if (acpi_drv->ops.notify)
 441                         acpi_device_remove_notify_handler(acpi_dev);
 442                 if (acpi_drv->ops.remove)
 443                         acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
 444         }
 445         acpi_dev->driver = NULL;
 446         acpi_dev->driver_data = NULL;
 447
 448         put_device(dev);
 449         return 0;
 450 }
 451
 452 struct bus_type acpi_bus_type = {
 453         .name           = "acpi",
 454         .suspend        = acpi_device_suspend,
 455         .resume         = acpi_device_resume,
 456         .match          = acpi_bus_match,
 457         .probe          = acpi_device_probe,
 458         .remove         = acpi_device_remove,
 459         .uevent         = acpi_device_uevent,
 460 };
 461
 462 static int acpi_device_register(struct acpi_device *device)
 463 {
 464         int result;
 465         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 466         int found = 0;
 467
 468         /*
 469          * Linkage
 470          * -------
 471          * Link this device to its parent and siblings.
 472          */
 473         INIT_LIST_HEAD(&device->children);
 474         INIT_LIST_HEAD(&device->node);
 475         INIT_LIST_HEAD(&device->wakeup_list);
 476
 477         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 478         if (!new_bus_id) {
 479                 printk(KERN_ERR PREFIX "Memory allocation error\n");
 480                 return -ENOMEM;
 481         }
 482
 483         mutex_lock(&acpi_device_lock);
 484         /*
 485          * Find suitable bus_id and instance number in acpi_bus_id_list
 486          * If failed, create one and link it into acpi_bus_id_list
 487          */
 488         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 489                 if (!strcmp(acpi_device_bus_id->bus_id,
 490                             acpi_device_hid(device))) {
 491                         acpi_device_bus_id->instance_no++;
 492                         found = 1;
 493                         kfree(new_bus_id);
 494                         break;
 495                 }
 496         }
 497         if (!found) {
 498                 acpi_device_bus_id = new_bus_id;
 499                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
 500                 acpi_device_bus_id->instance_no = 0;
 501                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 502         }
 503         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 504
 505         if (device->parent)
 506                 list_add_tail(&device->node, &device->parent->children);
 507
 508         if (device->wakeup.flags.valid)
 509                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 510         mutex_unlock(&acpi_device_lock);
 511
 512         if (device->parent)
 513                 device->dev.parent = &device->parent->dev;
 514         device->dev.bus = &acpi_bus_type;
 515         device->dev.release = &acpi_device_release;
 516         result = device_register(&device->dev);
 517         if (result) {
 518                 dev_err(&device->dev, "Error registering device\n");
 519                 goto end;
 520         }
 521
 522         result = acpi_device_setup_files(device);
 523         if (result)
 524                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 525                        dev_name(&device->dev));
 526
 527         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
 528         return 0;
 529 end:
 530         mutex_lock(&acpi_device_lock);
 531         if (device->parent)
 532                 list_del(&device->node);
 533         list_del(&device->wakeup_list);
 534         mutex_unlock(&acpi_device_lock);
 535         return result;
 536 }
 537
 538 static void acpi_device_unregister(struct acpi_device *device, int type)
 539 {
 540         mutex_lock(&acpi_device_lock);
 541         if (device->parent)
 542                 list_del(&device->node);
 543
 544         list_del(&device->wakeup_list);
 545         mutex_unlock(&acpi_device_lock);
 546
 547         acpi_detach_data(device->handle, acpi_bus_data_handler);
 548
 549         acpi_device_remove_files(device);
 550         device_unregister(&device->dev);
 551 }
 552
 553 /* --------------------------------------------------------------------------
 554                                  Driver Management
 555    -------------------------------------------------------------------------- */
 556 /**
 557  * acpi_bus_driver_init - add a device to a driver
 558  * @device: the device to add and initialize
 559  * @driver: driver for the device
 560  *
 561  * Used to initialize a device via its device driver.  Called whenever a
 562  * driver is bound to a device.  Invokes the driver's add() ops.
 563  */
 564 static int
 565 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
 566 {
 567         int result = 0;
 568
 569         if (!device || !driver)
 570                 return -EINVAL;
 571
 572         if (!driver->ops.add)
 573                 return -ENOSYS;
 574
 575         result = driver->ops.add(device);
 576         if (result) {
 577                 device->driver = NULL;
 578                 device->driver_data = NULL;
 579                 return result;
 580         }
 581
 582         device->driver = driver;
 583
 584         /*
 585          * TBD - Configuration Management: Assign resources to device based
 586          * upon possible configuration and currently allocated resources.
 587          */
 588
 589         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 590                           "Driver successfully bound to device\n"));
 591         return 0;
 592 }
 593
 594 static int acpi_start_single_object(struct acpi_device *device)
 595 {
 596         int result = 0;
 597         struct acpi_driver *driver;
 598
 599
 600         if (!(driver = device->driver))
 601                 return 0;
 602
 603         if (driver->ops.start) {
 604                 result = driver->ops.start(device);
 605                 if (result && driver->ops.remove)
 606                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
 607         }
 608
 609         return result;
 610 }
 611
 612 /**
 613  * acpi_bus_register_driver - register a driver with the ACPI bus
 614  * @driver: driver being registered
 615  *
 616  * Registers a driver with the ACPI bus.  Searches the namespace for all
 617  * devices that match the driver's criteria and binds.  Returns zero for
 618  * success or a negative error status for failure.
 619  */
 620 int acpi_bus_register_driver(struct acpi_driver *driver)
 621 {
 622         int ret;
 623
 624         if (acpi_disabled)
 625                 return -ENODEV;
 626         driver->drv.name = driver->name;
 627         driver->drv.bus = &acpi_bus_type;
 628         driver->drv.owner = driver->owner;
 629
 630         ret = driver_register(&driver->drv);
 631         return ret;
 632 }
 633
 634 EXPORT_SYMBOL(acpi_bus_register_driver);
 635
 636 /**
 637  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
 638  * @driver: driver to unregister
 639  *
 640  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
 641  * devices that match the driver's criteria and unbinds.
 642  */
 643 void acpi_bus_unregister_driver(struct acpi_driver *driver)
 644 {
 645         driver_unregister(&driver->drv);
 646 }
 647
 648 EXPORT_SYMBOL(acpi_bus_unregister_driver);
 649
 650 /* --------------------------------------------------------------------------
 651                                  Device Enumeration
 652    -------------------------------------------------------------------------- */
 653 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
 654 {
 655         acpi_status status;
 656         int ret;
 657         struct acpi_device *device;
 658
 659         /*
 660          * Fixed hardware devices do not appear in the namespace and do not
 661          * have handles, but we fabricate acpi_devices for them, so we have
 662          * to deal with them specially.
 663          */
 664         if (handle == NULL)
 665                 return acpi_root;
 666
 667         do {
 668                 status = acpi_get_parent(handle, &handle);
 669                 if (status == AE_NULL_ENTRY)
 670                         return NULL;
 671                 if (ACPI_FAILURE(status))
 672                         return acpi_root;
 673
 674                 ret = acpi_bus_get_device(handle, &device);
 675                 if (ret == 0)
 676                         return device;
 677         } while (1);
 678 }
 679
 680 acpi_status
 681 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 682 {
 683         acpi_status status;
 684         acpi_handle tmp;
 685         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 686         union acpi_object *obj;
 687
 688         status = acpi_get_handle(handle, "_EJD", &tmp);
 689         if (ACPI_FAILURE(status))
 690                 return status;
 691
 692         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 693         if (ACPI_SUCCESS(status)) {
 694                 obj = buffer.pointer;
 695                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 696                                          ejd);
 697                 kfree(buffer.pointer);
 698         }
 699         return status;
 700 }
 701 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 702
 703 void acpi_bus_data_handler(acpi_handle handle, void *context)
 704 {
 705
 706         /* TBD */
 707
 708         return;
 709 }
 710
 711 static int acpi_bus_get_perf_flags(struct acpi_device *device)
 712 {
 713         device->performance.state = ACPI_STATE_UNKNOWN;
 714         return 0;
 715 }
 716
 717 static acpi_status
 718 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
 719                                              union acpi_object *package)
 720 {
 721         int i = 0;
 722         union acpi_object *element = NULL;
 723
 724         if (!device || !package || (package->package.count < 2))
 725                 return AE_BAD_PARAMETER;
 726
 727         element = &(package->package.elements[0]);
 728         if (!element)
 729                 return AE_BAD_PARAMETER;
 730         if (element->type == ACPI_TYPE_PACKAGE) {
 731                 if ((element->package.count < 2) ||
 732                     (element->package.elements[0].type !=
 733                      ACPI_TYPE_LOCAL_REFERENCE)
 734                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 735                         return AE_BAD_DATA;
 736                 device->wakeup.gpe_device =
 737                     element->package.elements[0].reference.handle;
 738                 device->wakeup.gpe_number =
 739                     (u32) element->package.elements[1].integer.value;
 740         } else if (element->type == ACPI_TYPE_INTEGER) {
 741                 device->wakeup.gpe_number = element->integer.value;
 742         } else
 743                 return AE_BAD_DATA;
 744
 745         element = &(package->package.elements[1]);
 746         if (element->type != ACPI_TYPE_INTEGER) {
 747                 return AE_BAD_DATA;
 748         }
 749         device->wakeup.sleep_state = element->integer.value;
 750
 751         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
 752                 return AE_NO_MEMORY;
 753         }
 754         device->wakeup.resources.count = package->package.count - 2;
 755         for (i = 0; i < device->wakeup.resources.count; i++) {
 756                 element = &(package->package.elements[i + 2]);
 757                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
 758                         return AE_BAD_DATA;
 759
 760                 device->wakeup.resources.handles[i] = element->reference.handle;
 761         }
 762
 763         return AE_OK;
 764 }
 765
 766 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
 767 {
 768         struct acpi_device_id button_device_ids[] = {
 769                 {"PNP0C0D", 0},
 770                 {"PNP0C0C", 0},
 771                 {"PNP0C0E", 0},
 772                 {"", 0},
 773         };
 774         acpi_status status;
 775         acpi_event_status event_status;
 776
 777         device->wakeup.run_wake_count = 0;
 778         device->wakeup.flags.notifier_present = 0;
 779
 780         /* Power button, Lid switch always enable wakeup */
 781         if (!acpi_match_device_ids(device, button_device_ids)) {
 782                 device->wakeup.flags.run_wake = 1;
 783                 device->wakeup.flags.always_enabled = 1;
 784                 return;
 785         }
 786
 787         status = acpi_get_gpe_status(NULL, device->wakeup.gpe_number,
 788                                         ACPI_NOT_ISR, &event_status);
 789         if (status == AE_OK)
 790                 device->wakeup.flags.run_wake =
 791                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
 792 }
 793
 794 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 795 {
 796         acpi_status status = 0;
 797         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 798         union acpi_object *package = NULL;
 799         int psw_error;
 800
 801         /* _PRW */
 802         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
 803         if (ACPI_FAILURE(status)) {
 804                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 805                 goto end;
 806         }
 807
 808         package = (union acpi_object *)buffer.pointer;
 809         status = acpi_bus_extract_wakeup_device_power_package(device, package);
 810         if (ACPI_FAILURE(status)) {
 811                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
 812                 goto end;
 813         }
 814
 815         kfree(buffer.pointer);
 816
 817         device->wakeup.flags.valid = 1;
 818         device->wakeup.prepare_count = 0;
 819         acpi_bus_set_run_wake_flags(device);
 820         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
 821          * system for the ACPI device with the _PRW object.
 822          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 823          * So it is necessary to call _DSW object first. Only when it is not
 824          * present will the _PSW object used.
 825          */
 826         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
 827         if (psw_error)
 828                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 829                                 "error in _DSW or _PSW evaluation\n"));
 830
 831 end:
 832         if (ACPI_FAILURE(status))
 833                 device->flags.wake_capable = 0;
 834         return 0;
 835 }
 836
 837 static int acpi_bus_get_power_flags(struct acpi_device *device)
 838 {
 839         acpi_status status = 0;
 840         acpi_handle handle = NULL;
 841         u32 i = 0;
 842
 843
 844         /*
 845          * Power Management Flags
 846          */
 847         status = acpi_get_handle(device->handle, "_PSC", &handle);
 848         if (ACPI_SUCCESS(status))
 849                 device->power.flags.explicit_get = 1;
 850         status = acpi_get_handle(device->handle, "_IRC", &handle);
 851         if (ACPI_SUCCESS(status))
 852                 device->power.flags.inrush_current = 1;
 853
 854         /*
 855          * Enumerate supported power management states
 856          */
 857         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
 858                 struct acpi_device_power_state *ps = &device->power.states[i];
 859                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
 860
 861                 /* Evaluate "_PRx" to se if power resources are referenced */
 862                 acpi_evaluate_reference(device->handle, object_name, NULL,
 863                                         &ps->resources);
 864                 if (ps->resources.count) {
 865                         device->power.flags.power_resources = 1;
 866                         ps->flags.valid = 1;
 867                 }
 868
 869                 /* Evaluate "_PSx" to see if we can do explicit sets */
 870                 object_name[2] = 'S';
 871                 status = acpi_get_handle(device->handle, object_name, &handle);
 872                 if (ACPI_SUCCESS(status)) {
 873                         ps->flags.explicit_set = 1;
 874                         ps->flags.valid = 1;
 875                 }
 876
 877                 /* State is valid if we have some power control */
 878                 if (ps->resources.count || ps->flags.explicit_set)
 879                         ps->flags.valid = 1;
 880
 881                 ps->power = -1; /* Unknown - driver assigned */
 882                 ps->latency = -1;       /* Unknown - driver assigned */
 883         }
 884
 885         /* Set defaults for D0 and D3 states (always valid) */
 886         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 887         device->power.states[ACPI_STATE_D0].power = 100;
 888         device->power.states[ACPI_STATE_D3].flags.valid = 1;
 889         device->power.states[ACPI_STATE_D3].power = 0;
 890
 891         /* TBD: System wake support and resource requirements. */
 892
 893         device->power.state = ACPI_STATE_UNKNOWN;
 894         acpi_bus_get_power(device->handle, &(device->power.state));
 895
 896         return 0;
 897 }
 898
 899 static int acpi_bus_get_flags(struct acpi_device *device)
 900 {
 901         acpi_status status = AE_OK;
 902         acpi_handle temp = NULL;
 903
 904
 905         /* Presence of _STA indicates 'dynamic_status' */
 906         status = acpi_get_handle(device->handle, "_STA", &temp);
 907         if (ACPI_SUCCESS(status))
 908                 device->flags.dynamic_status = 1;
 909
 910         /* Presence of _RMV indicates 'removable' */
 911         status = acpi_get_handle(device->handle, "_RMV", &temp);
 912         if (ACPI_SUCCESS(status))
 913                 device->flags.removable = 1;
 914
 915         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 916         status = acpi_get_handle(device->handle, "_EJD", &temp);
 917         if (ACPI_SUCCESS(status))
 918                 device->flags.ejectable = 1;
 919         else {
 920                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
 921                 if (ACPI_SUCCESS(status))
 922                         device->flags.ejectable = 1;
 923         }
 924
 925         /* Presence of _LCK indicates 'lockable' */
 926         status = acpi_get_handle(device->handle, "_LCK", &temp);
 927         if (ACPI_SUCCESS(status))
 928                 device->flags.lockable = 1;
 929
 930         /* Presence of _PS0|_PR0 indicates 'power manageable' */
 931         status = acpi_get_handle(device->handle, "_PS0", &temp);
 932         if (ACPI_FAILURE(status))
 933                 status = acpi_get_handle(device->handle, "_PR0", &temp);
 934         if (ACPI_SUCCESS(status))
 935                 device->flags.power_manageable = 1;
 936
 937         /* Presence of _PRW indicates wake capable */
 938         status = acpi_get_handle(device->handle, "_PRW", &temp);
 939         if (ACPI_SUCCESS(status))
 940                 device->flags.wake_capable = 1;
 941
 942         /* TBD: Performance management */
 943
 944         return 0;
 945 }
 946
 947 static void acpi_device_get_busid(struct acpi_device *device)
 948 {
 949         char bus_id[5] = { '?', 0 };
 950         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
 951         int i = 0;
 952
 953         /*
 954          * Bus ID
 955          * ------
 956          * The device's Bus ID is simply the object name.
 957          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
 958          */
 959         if (ACPI_IS_ROOT_DEVICE(device)) {
 960                 strcpy(device->pnp.bus_id, "ACPI");
 961                 return;
 962         }
 963
 964         switch (device->device_type) {
 965         case ACPI_BUS_TYPE_POWER_BUTTON:
 966                 strcpy(device->pnp.bus_id, "PWRF");
 967                 break;
 968         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 969                 strcpy(device->pnp.bus_id, "SLPF");
 970                 break;
 971         default:
 972                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
 973                 /* Clean up trailing underscores (if any) */
 974                 for (i = 3; i > 1; i--) {
 975                         if (bus_id[i] == '_')
 976                                 bus_id[i] = '\0';
 977                         else
 978                                 break;
 979                 }
 980                 strcpy(device->pnp.bus_id, bus_id);
 981                 break;
 982         }
 983 }
 984
 985 /*
 986  * acpi_bay_match - see if a device is an ejectable driver bay
 987  *
 988  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
 989  * then we can safely call it an ejectable drive bay
 990  */
 991 static int acpi_bay_match(struct acpi_device *device){
 992         acpi_status status;
 993         acpi_handle handle;
 994         acpi_handle tmp;
 995         acpi_handle phandle;
 996
 997         handle = device->handle;
 998
 999         status = acpi_get_handle(handle, "_EJ0", &tmp);
1000         if (ACPI_FAILURE(status))
1001                 return -ENODEV;
1002
1003         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
1004                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
1005                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
1006                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
1007                 return 0;
1008
1009         if (acpi_get_parent(handle, &phandle))
1010                 return -ENODEV;
1011
1012         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
1013                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
1014                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
1015                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
1016                 return 0;
1017
1018         return -ENODEV;
1019 }
1020
1021 /*
1022  * acpi_dock_match - see if a device has a _DCK method
1023  */
1024 static int acpi_dock_match(struct acpi_device *device)
1025 {
1026         acpi_handle tmp;
1027         return acpi_get_handle(device->handle, "_DCK", &tmp);
1028 }
1029
1030 char *acpi_device_hid(struct acpi_device *device)
1031 {
1032         struct acpi_hardware_id *hid;
1033
1034         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1035         return hid->id;
1036 }
1037 EXPORT_SYMBOL(acpi_device_hid);
1038
1039 static void acpi_add_id(struct acpi_device *device, const char *dev_id)
1040 {
1041         struct acpi_hardware_id *id;
1042
1043         id = kmalloc(sizeof(*id), GFP_KERNEL);
1044         if (!id)
1045                 return;
1046
1047         id->id = kmalloc(strlen(dev_id) + 1, GFP_KERNEL);
1048         if (!id->id) {
1049                 kfree(id);
1050                 return;
1051         }
1052
1053         strcpy(id->id, dev_id);
1054         list_add_tail(&id->list, &device->pnp.ids);
1055 }
1056
1057 /*
1058  * Old IBM workstations have a DSDT bug wherein the SMBus object
1059  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1060  * prefix.  Work around this.
1061  */
1062 static int acpi_ibm_smbus_match(struct acpi_device *device)
1063 {
1064         acpi_handle h_dummy;
1065         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1066         int result;
1067
1068         if (!dmi_name_in_vendors("IBM"))
1069                 return -ENODEV;
1070
1071         /* Look for SMBS object */
1072         result = acpi_get_name(device->handle, ACPI_SINGLE_NAME, &path);
1073         if (result)
1074                 return result;
1075
1076         if (strcmp("SMBS", path.pointer)) {
1077                 result = -ENODEV;
1078                 goto out;
1079         }
1080
1081         /* Does it have the necessary (but misnamed) methods? */
1082         result = -ENODEV;
1083         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "SBI", &h_dummy)) &&
1084             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBR", &h_dummy)) &&
1085             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBW", &h_dummy)))
1086                 result = 0;
1087 out:
1088         kfree(path.pointer);
1089         return result;
1090 }
1091
1092 static void acpi_device_set_id(struct acpi_device *device)
1093 {
1094         acpi_status status;
1095         struct acpi_device_info *info;
1096         struct acpica_device_id_list *cid_list;
1097         int i;
1098
1099         switch (device->device_type) {
1100         case ACPI_BUS_TYPE_DEVICE:
1101                 if (ACPI_IS_ROOT_DEVICE(device)) {
1102                         acpi_add_id(device, ACPI_SYSTEM_HID);
1103                         break;
1104                 }
1105
1106                 status = acpi_get_object_info(device->handle, &info);
1107                 if (ACPI_FAILURE(status)) {
1108                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1109                         return;
1110                 }
1111
1112                 if (info->valid & ACPI_VALID_HID)
1113                         acpi_add_id(device, info->hardware_id.string);
1114                 if (info->valid & ACPI_VALID_CID) {
1115                         cid_list = &info->compatible_id_list;
1116                         for (i = 0; i < cid_list->count; i++)
1117                                 acpi_add_id(device, cid_list->ids[i].string);
1118                 }
1119 #ifdef CONFIG_PCI_GUESTDEV
1120                 if (info->valid & ACPI_VALID_UID)
1121                         device->pnp.unique_id = kstrdup(info->unique_id.string,
1122                                                         GFP_KERNEL);
1123 #endif
1124                 if (info->valid & ACPI_VALID_ADR) {
1125                         device->pnp.bus_address = info->address;
1126                         device->flags.bus_address = 1;
1127                 }
1128
1129                 kfree(info);
1130
1131                 /*
1132                  * Some devices don't reliably have _HIDs & _CIDs, so add
1133                  * synthetic HIDs to make sure drivers can find them.
1134                  */
1135                 if (acpi_is_video_device(device))
1136                         acpi_add_id(device, ACPI_VIDEO_HID);
1137                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1138                         acpi_add_id(device, ACPI_BAY_HID);
1139                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1140                         acpi_add_id(device, ACPI_DOCK_HID);
1141                 else if (!acpi_ibm_smbus_match(device))
1142                         acpi_add_id(device, ACPI_SMBUS_IBM_HID);
1143                 else if (!acpi_device_hid(device) &&
1144                          ACPI_IS_ROOT_DEVICE(device->parent)) {
1145                         acpi_add_id(device, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1146                         strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1147                         strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1148                 }
1149
1150                 break;
1151         case ACPI_BUS_TYPE_POWER:
1152                 acpi_add_id(device, ACPI_POWER_HID);
1153                 break;
1154         case ACPI_BUS_TYPE_PROCESSOR:
1155                 acpi_add_id(device, ACPI_PROCESSOR_OBJECT_HID);
1156                 break;
1157         case ACPI_BUS_TYPE_THERMAL:
1158                 acpi_add_id(device, ACPI_THERMAL_HID);
1159                 break;
1160         case ACPI_BUS_TYPE_POWER_BUTTON:
1161                 acpi_add_id(device, ACPI_BUTTON_HID_POWERF);
1162                 break;
1163         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1164                 acpi_add_id(device, ACPI_BUTTON_HID_SLEEPF);
1165                 break;
1166         }
1167
1168         /*
1169          * We build acpi_devices for some objects that don't have _HID or _CID,
1170          * e.g., PCI bridges and slots.  Drivers can't bind to these objects,
1171          * but we do use them indirectly by traversing the acpi_device tree.
1172          * This generic ID isn't useful for driver binding, but it provides
1173          * the useful property that "every acpi_device has an ID."
1174          */
1175         if (list_empty(&device->pnp.ids))
1176                 acpi_add_id(device, "device");
1177 }
1178
1179 static int acpi_device_set_context(struct acpi_device *device)
1180 {
1181         acpi_status status;
1182
1183         /*
1184          * Context
1185          * -------
1186          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1187          * resolutions from handle->device very efficient.  Fixed hardware
1188          * devices have no handles, so we skip them.
1189          */
1190         if (!device->handle)
1191                 return 0;
1192
1193         status = acpi_attach_data(device->handle,
1194                                   acpi_bus_data_handler, device);
1195         if (ACPI_SUCCESS(status))
1196                 return 0;
1197
1198         printk(KERN_ERR PREFIX "Error attaching device data\n");
1199         return -ENODEV;
1200 }
1201
1202 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1203 {
1204         if (!dev)
1205                 return -EINVAL;
1206
1207         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1208         device_release_driver(&dev->dev);
1209
1210         if (!rmdevice)
1211                 return 0;
1212
1213         /*
1214          * unbind _ADR-Based Devices when hot removal
1215          */
1216         if (dev->flags.bus_address) {
1217                 if ((dev->parent) && (dev->parent->ops.unbind))
1218                         dev->parent->ops.unbind(dev);
1219         }
1220         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1221
1222         return 0;
1223 }
1224
1225 static int acpi_add_single_object(struct acpi_device **child,
1226                                   acpi_handle handle, int type,
1227                                   unsigned long long sta,
1228                                   struct acpi_bus_ops *ops)
1229 {
1230         int result;
1231         struct acpi_device *device;
1232         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1233
1234         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1235         if (!device) {
1236                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1237                 return -ENOMEM;
1238         }
1239
1240         INIT_LIST_HEAD(&device->pnp.ids);
1241         device->device_type = type;
1242         device->handle = handle;
1243         device->parent = acpi_bus_get_parent(handle);
1244         device->bus_ops = *ops; /* workround for not call .start */
1245         STRUCT_TO_INT(device->status) = sta;
1246
1247         acpi_device_get_busid(device);
1248
1249         /*
1250          * Flags
1251          * -----
1252          * Note that we only look for object handles -- cannot evaluate objects
1253          * until we know the device is present and properly initialized.
1254          */
1255         result = acpi_bus_get_flags(device);
1256         if (result)
1257                 goto end;
1258
1259         /*
1260          * Initialize Device
1261          * -----------------
1262          * TBD: Synch with Core's enumeration/initialization process.
1263          */
1264         acpi_device_set_id(device);
1265
1266         /*
1267          * Power Management
1268          * ----------------
1269          */
1270         if (device->flags.power_manageable) {
1271                 result = acpi_bus_get_power_flags(device);
1272                 if (result)
1273                         goto end;
1274         }
1275
1276         /*
1277          * Wakeup device management
1278          *-----------------------
1279          */
1280         if (device->flags.wake_capable) {
1281                 result = acpi_bus_get_wakeup_device_flags(device);
1282                 if (result)
1283                         goto end;
1284         }
1285
1286         /*
1287          * Performance Management
1288          * ----------------------
1289          */
1290         if (device->flags.performance_manageable) {
1291                 result = acpi_bus_get_perf_flags(device);
1292                 if (result)
1293                         goto end;
1294         }
1295
1296         if ((result = acpi_device_set_context(device)))
1297                 goto end;
1298
1299         result = acpi_device_register(device);
1300
1301         /*
1302          * Bind _ADR-Based Devices when hot add
1303          */
1304         if (device->flags.bus_address) {
1305                 if (device->parent && device->parent->ops.bind)
1306                         device->parent->ops.bind(device);
1307         }
1308
1309 end:
1310         if (!result) {
1311                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1312                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1313                         "Adding %s [%s] parent %s\n", dev_name(&device->dev),
1314                          (char *) buffer.pointer,
1315                          device->parent ? dev_name(&device->parent->dev) :
1316                                           "(null)"));
1317                 kfree(buffer.pointer);
1318                 *child = device;
1319         } else
1320                 acpi_device_release(&device->dev);
1321
1322         return result;
1323 }
1324
1325 #define ACPI_STA_DEFAULT (ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED | \
1326                           ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING)
1327
1328 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1329                                     unsigned long long *sta)
1330 {
1331         acpi_status status;
1332         acpi_object_type acpi_type;
1333
1334         status = acpi_get_type(handle, &acpi_type);
1335         if (ACPI_FAILURE(status))
1336                 return -ENODEV;
1337
1338         switch (acpi_type) {
1339         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1340         case ACPI_TYPE_DEVICE:
1341                 *type = ACPI_BUS_TYPE_DEVICE;
1342                 status = acpi_bus_get_status_handle(handle, sta);
1343                 if (ACPI_FAILURE(status))
1344                         return -ENODEV;
1345                 break;
1346         case ACPI_TYPE_PROCESSOR:
1347                 *type = ACPI_BUS_TYPE_PROCESSOR;
1348                 status = acpi_bus_get_status_handle(handle, sta);
1349                 if (ACPI_FAILURE(status))
1350                         return -ENODEV;
1351                 break;
1352         case ACPI_TYPE_THERMAL:
1353                 *type = ACPI_BUS_TYPE_THERMAL;
1354                 *sta = ACPI_STA_DEFAULT;
1355                 break;
1356         case ACPI_TYPE_POWER:
1357                 *type = ACPI_BUS_TYPE_POWER;
1358                 *sta = ACPI_STA_DEFAULT;
1359                 break;
1360         default:
1361                 return -ENODEV;
1362         }
1363
1364         return 0;
1365 }
1366
1367 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl,
1368                                       void *context, void **return_value)
1369 {
1370         struct acpi_bus_ops *ops = context;
1371         int type;
1372         unsigned long long sta;
1373         struct acpi_device *device;
1374         acpi_status status;
1375         int result;
1376
1377         result = acpi_bus_type_and_status(handle, &type, &sta);
1378         if (result)
1379                 return AE_OK;
1380
1381         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1382             !(sta & ACPI_STA_DEVICE_FUNCTIONING))
1383                 return AE_CTRL_DEPTH;
1384
1385         /*
1386          * We may already have an acpi_device from a previous enumeration.  If
1387          * so, we needn't add it again, but we may still have to start it.
1388          */
1389         device = NULL;
1390         acpi_bus_get_device(handle, &device);
1391         if (ops->acpi_op_add && !device)
1392                 acpi_add_single_object(&device, handle, type, sta, ops);
1393
1394         if (!device)
1395                 return AE_CTRL_DEPTH;
1396
1397         if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1398                 status = acpi_start_single_object(device);
1399                 if (ACPI_FAILURE(status))
1400                         return AE_CTRL_DEPTH;
1401         }
1402
1403         if (!*return_value)
1404                 *return_value = device;
1405         return AE_OK;
1406 }
1407
1408 static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops,
1409                          struct acpi_device **child)
1410 {
1411         acpi_status status;
1412         void *device = NULL;
1413
1414         status = acpi_bus_check_add(handle, 0, ops, &device);
1415         if (ACPI_SUCCESS(status))
1416                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1417                                     acpi_bus_check_add, NULL, ops, &device);
1418
1419         if (child)
1420                 *child = device;
1421
1422         if (device)
1423                 return 0;
1424         else
1425                 return -ENODEV;
1426 }
1427
1428 /*
1429  * acpi_bus_add and acpi_bus_start
1430  *
1431  * scan a given ACPI tree and (probably recently hot-plugged)
1432  * create and add or starts found devices.
1433  *
1434  * If no devices were found -ENODEV is returned which does not
1435  * mean that this is a real error, there just have been no suitable
1436  * ACPI objects in the table trunk from which the kernel could create
1437  * a device and add/start an appropriate driver.
1438  */
1439
1440 int
1441 acpi_bus_add(struct acpi_device **child,
1442              struct acpi_device *parent, acpi_handle handle, int type)
1443 {
1444         struct acpi_bus_ops ops;
1445
1446         memset(&ops, 0, sizeof(ops));
1447         ops.acpi_op_add = 1;
1448
1449         return acpi_bus_scan(handle, &ops, child);
1450 }
1451 EXPORT_SYMBOL(acpi_bus_add);
1452
1453 int acpi_bus_start(struct acpi_device *device)
1454 {
1455         struct acpi_bus_ops ops;
1456
1457         if (!device)
1458                 return -EINVAL;
1459
1460         memset(&ops, 0, sizeof(ops));
1461         ops.acpi_op_start = 1;
1462
1463         return acpi_bus_scan(device->handle, &ops, NULL);
1464 }
1465 EXPORT_SYMBOL(acpi_bus_start);
1466
1467 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1468 {
1469         acpi_status status;
1470         struct acpi_device *parent, *child;
1471         acpi_handle phandle, chandle;
1472         acpi_object_type type;
1473         u32 level = 1;
1474         int err = 0;
1475
1476         parent = start;
1477         phandle = start->handle;
1478         child = chandle = NULL;
1479
1480         while ((level > 0) && parent && (!err)) {
1481                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1482                                               chandle, &chandle);
1483
1484                 /*
1485                  * If this scope is exhausted then move our way back up.
1486                  */
1487                 if (ACPI_FAILURE(status)) {
1488                         level--;
1489                         chandle = phandle;
1490                         acpi_get_parent(phandle, &phandle);
1491                         child = parent;
1492                         parent = parent->parent;
1493
1494                         if (level == 0)
1495                                 err = acpi_bus_remove(child, rmdevice);
1496                         else
1497                                 err = acpi_bus_remove(child, 1);
1498
1499                         continue;
1500                 }
1501
1502                 status = acpi_get_type(chandle, &type);
1503                 if (ACPI_FAILURE(status)) {
1504                         continue;
1505                 }
1506                 /*
1507                  * If there is a device corresponding to chandle then
1508                  * parse it (depth-first).
1509                  */
1510                 if (acpi_bus_get_device(chandle, &child) == 0) {
1511                         level++;
1512                         phandle = chandle;
1513                         chandle = NULL;
1514                         parent = child;
1515                 }
1516                 continue;
1517         }
1518         return err;
1519 }
1520 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1521
1522 static int acpi_bus_scan_fixed(void)
1523 {
1524         int result = 0;
1525         struct acpi_device *device = NULL;
1526         struct acpi_bus_ops ops;
1527
1528         memset(&ops, 0, sizeof(ops));
1529         ops.acpi_op_add = 1;
1530         ops.acpi_op_start = 1;
1531
1532         /*
1533          * Enumerate all fixed-feature devices.
1534          */
1535         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1536                 result = acpi_add_single_object(&device, NULL,
1537                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1538                                                 ACPI_STA_DEFAULT,
1539                                                 &ops);
1540         }
1541
1542         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1543                 result = acpi_add_single_object(&device, NULL,
1544                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1545                                                 ACPI_STA_DEFAULT,
1546                                                 &ops);
1547         }
1548
1549         return result;
1550 }
1551
1552 int __init acpi_scan_init(void)
1553 {
1554         int result;
1555         struct acpi_bus_ops ops;
1556
1557         memset(&ops, 0, sizeof(ops));
1558         ops.acpi_op_add = 1;
1559         ops.acpi_op_start = 1;
1560
1561         result = bus_register(&acpi_bus_type);
1562         if (result) {
1563                 /* We don't want to quit even if we failed to add suspend/resume */
1564                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1565         }
1566
1567         /*
1568          * Enumerate devices in the ACPI namespace.
1569          */
1570         result = acpi_bus_scan(ACPI_ROOT_OBJECT, &ops, &acpi_root);
1571
1572         if (!result)
1573                 result = acpi_bus_scan_fixed();
1574
1575         if (result)
1576                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1577
1578         return result;
1579 }