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 #include <linux/nls.h>
  14
  15 #include <acpi/acpi_drivers.h>
  16
  17 #include "internal.h"
  18
  19 #define _COMPONENT              ACPI_BUS_COMPONENT
  20 ACPI_MODULE_NAME("scan");
  21 #define STRUCT_TO_INT(s)        (*((int*)&s))
  22 extern struct acpi_device *acpi_root;
  23
  24 #define ACPI_BUS_CLASS                  "system_bus"
  25 #define ACPI_BUS_HID                    "LNXSYBUS"
  26 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  27
  28 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
  29
  30 static const char *dummy_hid = "device";
  31
  32 static LIST_HEAD(acpi_device_list);
  33 static LIST_HEAD(acpi_bus_id_list);
  34 DEFINE_MUTEX(acpi_device_lock);
  35 LIST_HEAD(acpi_wakeup_device_list);
  36
  37 struct acpi_device_bus_id{
  38         char bus_id[15];
  39         unsigned int instance_no;
  40         struct list_head node;
  41 };
  42
  43 /*
  44  * Creates hid/cid(s) string needed for modalias and uevent
  45  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
  46  * char *modalias: "acpi:IBM0001:ACPI0001"
  47 */
  48 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
  49                            int size)
  50 {
  51         int len;
  52         int count;
  53         struct acpi_hardware_id *id;
  54
  55         if (list_empty(&acpi_dev->pnp.ids))
  56                 return 0;
  57
  58         len = snprintf(modalias, size, "acpi:");
  59         size -= len;
  60
  61         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
  62                 count = snprintf(&modalias[len], size, "%s:", id->id);
  63                 if (count < 0 || count >= size)
  64                         return -EINVAL;
  65                 len += count;
  66                 size -= count;
  67         }
  68
  69         modalias[len] = '\0';
  70         return len;
  71 }
  72
  73 static ssize_t
  74 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
  75         struct acpi_device *acpi_dev = to_acpi_device(dev);
  76         int len;
  77
  78         /* Device has no HID and no CID or string is >1024 */
  79         len = create_modalias(acpi_dev, buf, 1024);
  80         if (len <= 0)
  81                 return 0;
  82         buf[len++] = '\n';
  83         return len;
  84 }
  85 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
  86
  87 /**
  88  * acpi_bus_hot_remove_device: hot-remove a device and its children
  89  * @context: struct acpi_eject_event pointer (freed in this func)
  90  *
  91  * Hot-remove a device and its children. This function frees up the
  92  * memory space passed by arg context, so that the caller may call
  93  * this function asynchronously through acpi_os_hotplug_execute().
  94  */
  95 void acpi_bus_hot_remove_device(void *context)
  96 {
  97         struct acpi_eject_event *ej_event = (struct acpi_eject_event *) context;
  98         struct acpi_device *device;
  99         acpi_handle handle = ej_event->handle;
 100         struct acpi_object_list arg_list;
 101         union acpi_object arg;
 102         acpi_status status = AE_OK;
 103         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */
 104
 105         if (acpi_bus_get_device(handle, &device))
 106                 goto err_out;
 107
 108         if (!device)
 109                 goto err_out;
 110
 111         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 112                 "Hot-removing device %s...\n", dev_name(&device->dev)));
 113
 114         if (acpi_bus_trim(device, 1)) {
 115                 printk(KERN_ERR PREFIX
 116                                 "Removing device failed\n");
 117                 goto err_out;
 118         }
 119
 120         /* power off device */
 121         status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
 122         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
 123                 printk(KERN_WARNING PREFIX
 124                                 "Power-off device failed\n");
 125
 126         if (device->flags.lockable) {
 127                 arg_list.count = 1;
 128                 arg_list.pointer = &arg;
 129                 arg.type = ACPI_TYPE_INTEGER;
 130                 arg.integer.value = 0;
 131                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
 132         }
 133
 134         arg_list.count = 1;
 135         arg_list.pointer = &arg;
 136         arg.type = ACPI_TYPE_INTEGER;
 137         arg.integer.value = 1;
 138
 139         /*
 140          * TBD: _EJD support.
 141          */
 142         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
 143         if (ACPI_FAILURE(status)) {
 144                 if (status != AE_NOT_FOUND)
 145                         printk(KERN_WARNING PREFIX
 146                                         "Eject device failed\n");
 147                 goto err_out;
 148         }
 149
 150         kfree(context);
 151         return;
 152
 153 err_out:
 154         /* Inform firmware the hot-remove operation has completed w/ error */
 155         (void) acpi_evaluate_hotplug_ost(handle,
 156                                 ej_event->event, ost_code, NULL);
 157         kfree(context);
 158         return;
 159 }
 160
 161 static ssize_t
 162 acpi_eject_store(struct device *d, struct device_attribute *attr,
 163                 const char *buf, size_t count)
 164 {
 165         int ret = count;
 166         acpi_status status;
 167         acpi_object_type type = 0;
 168         struct acpi_device *acpi_device = to_acpi_device(d);
 169         struct acpi_eject_event *ej_event;
 170
 171         if ((!count) || (buf[0] != '1')) {
 172                 return -EINVAL;
 173         }
 174 #ifndef FORCE_EJECT
 175         if (acpi_device->driver == NULL) {
 176                 ret = -ENODEV;
 177                 goto err;
 178         }
 179 #endif
 180         status = acpi_get_type(acpi_device->handle, &type);
 181         if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
 182                 ret = -ENODEV;
 183                 goto err;
 184         }
 185
 186         ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
 187         if (!ej_event) {
 188                 ret = -ENOMEM;
 189                 goto err;
 190         }
 191
 192         ej_event->handle = acpi_device->handle;
 193         if (acpi_device->flags.eject_pending) {
 194                 /* event originated from ACPI eject notification */
 195                 ej_event->event = ACPI_NOTIFY_EJECT_REQUEST;
 196                 acpi_device->flags.eject_pending = 0;
 197         } else {
 198                 /* event originated from user */
 199                 ej_event->event = ACPI_OST_EC_OSPM_EJECT;
 200                 (void) acpi_evaluate_hotplug_ost(ej_event->handle,
 201                         ej_event->event, ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 202         }
 203
 204         acpi_os_hotplug_execute(acpi_bus_hot_remove_device, (void *)ej_event);
 205 err:
 206         return ret;
 207 }
 208
 209 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 210
 211 static ssize_t
 212 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 213         struct acpi_device *acpi_dev = to_acpi_device(dev);
 214
 215         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
 216 }
 217 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 218
 219 static ssize_t
 220 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 221         struct acpi_device *acpi_dev = to_acpi_device(dev);
 222         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 223         int result;
 224
 225         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 226         if (result)
 227                 goto end;
 228
 229         result = sprintf(buf, "%s\n", (char*)path.pointer);
 230         kfree(path.pointer);
 231 end:
 232         return result;
 233 }
 234 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 235
 236 /* sysfs file that shows description text from the ACPI _STR method */
 237 static ssize_t description_show(struct device *dev,
 238                                 struct device_attribute *attr,
 239                                 char *buf) {
 240         struct acpi_device *acpi_dev = to_acpi_device(dev);
 241         int result;
 242
 243         if (acpi_dev->pnp.str_obj == NULL)
 244                 return 0;
 245
 246         /*
 247          * The _STR object contains a Unicode identifier for a device.
 248          * We need to convert to utf-8 so it can be displayed.
 249          */
 250         result = utf16s_to_utf8s(
 251                 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
 252                 acpi_dev->pnp.str_obj->buffer.length,
 253                 UTF16_LITTLE_ENDIAN, buf,
 254                 PAGE_SIZE);
 255
 256         buf[result++] = '\n';
 257
 258         return result;
 259 }
 260 static DEVICE_ATTR(description, 0444, description_show, NULL);
 261
 262 static int acpi_device_setup_files(struct acpi_device *dev)
 263 {
 264         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 265         acpi_status status;
 266         acpi_handle temp;
 267         int result = 0;
 268
 269         /*
 270          * Devices gotten from FADT don't have a "path" attribute
 271          */
 272         if (dev->handle) {
 273                 result = device_create_file(&dev->dev, &dev_attr_path);
 274                 if (result)
 275                         goto end;
 276         }
 277
 278         if (!list_empty(&dev->pnp.ids)) {
 279                 result = device_create_file(&dev->dev, &dev_attr_hid);
 280                 if (result)
 281                         goto end;
 282
 283                 result = device_create_file(&dev->dev, &dev_attr_modalias);
 284                 if (result)
 285                         goto end;
 286         }
 287
 288         /*
 289          * If device has _STR, 'description' file is created
 290          */
 291         status = acpi_get_handle(dev->handle, "_STR", &temp);
 292         if (ACPI_SUCCESS(status)) {
 293                 status = acpi_evaluate_object(dev->handle, "_STR",
 294                                         NULL, &buffer);
 295                 if (ACPI_FAILURE(status))
 296                         buffer.pointer = NULL;
 297                 dev->pnp.str_obj = buffer.pointer;
 298                 result = device_create_file(&dev->dev, &dev_attr_description);
 299                 if (result)
 300                         goto end;
 301         }
 302
 303         /*
 304          * If device has _EJ0, 'eject' file is created that is used to trigger
 305          * hot-removal function from userland.
 306          */
 307         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 308         if (ACPI_SUCCESS(status))
 309                 result = device_create_file(&dev->dev, &dev_attr_eject);
 310 end:
 311         return result;
 312 }
 313
 314 static void acpi_device_remove_files(struct acpi_device *dev)
 315 {
 316         acpi_status status;
 317         acpi_handle temp;
 318
 319         /*
 320          * If device has _STR, remove 'description' file
 321          */
 322         status = acpi_get_handle(dev->handle, "_STR", &temp);
 323         if (ACPI_SUCCESS(status)) {
 324                 kfree(dev->pnp.str_obj);
 325                 device_remove_file(&dev->dev, &dev_attr_description);
 326         }
 327         /*
 328          * If device has _EJ0, remove 'eject' file.
 329          */
 330         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 331         if (ACPI_SUCCESS(status))
 332                 device_remove_file(&dev->dev, &dev_attr_eject);
 333
 334         device_remove_file(&dev->dev, &dev_attr_modalias);
 335         device_remove_file(&dev->dev, &dev_attr_hid);
 336         if (dev->handle)
 337                 device_remove_file(&dev->dev, &dev_attr_path);
 338 }
 339 /* --------------------------------------------------------------------------
 340                         ACPI Bus operations
 341    -------------------------------------------------------------------------- */
 342
 343 int acpi_match_device_ids(struct acpi_device *device,
 344                           const struct acpi_device_id *ids)
 345 {
 346         const struct acpi_device_id *id;
 347         struct acpi_hardware_id *hwid;
 348
 349         /*
 350          * If the device is not present, it is unnecessary to load device
 351          * driver for it.
 352          */
 353         if (!device->status.present)
 354                 return -ENODEV;
 355
 356         for (id = ids; id->id[0]; id++)
 357                 list_for_each_entry(hwid, &device->pnp.ids, list)
 358                         if (!strcmp((char *) id->id, hwid->id))
 359                                 return 0;
 360
 361         return -ENOENT;
 362 }
 363 EXPORT_SYMBOL(acpi_match_device_ids);
 364
 365 static void acpi_free_ids(struct acpi_device *device)
 366 {
 367         struct acpi_hardware_id *id, *tmp;
 368
 369         list_for_each_entry_safe(id, tmp, &device->pnp.ids, list) {
 370                 kfree(id->id);
 371                 kfree(id);
 372         }
 373 }
 374
 375 static void acpi_device_release(struct device *dev)
 376 {
 377         struct acpi_device *acpi_dev = to_acpi_device(dev);
 378
 379         acpi_free_ids(acpi_dev);
 380         kfree(acpi_dev);
 381 }
 382
 383 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 384 {
 385         struct acpi_device *acpi_dev = to_acpi_device(dev);
 386         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 387
 388         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 389 }
 390
 391 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 392 {
 393         struct acpi_device *acpi_dev = to_acpi_device(dev);
 394         int len;
 395
 396         if (list_empty(&acpi_dev->pnp.ids))
 397                 return 0;
 398
 399         if (add_uevent_var(env, "MODALIAS="))
 400                 return -ENOMEM;
 401         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 402                               sizeof(env->buf) - env->buflen);
 403         if (len >= (sizeof(env->buf) - env->buflen))
 404                 return -ENOMEM;
 405         env->buflen += len;
 406         return 0;
 407 }
 408
 409 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 410 {
 411         struct acpi_device *device = data;
 412
 413         device->driver->ops.notify(device, event);
 414 }
 415
 416 static acpi_status acpi_device_notify_fixed(void *data)
 417 {
 418         struct acpi_device *device = data;
 419
 420         /* Fixed hardware devices have no handles */
 421         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 422         return AE_OK;
 423 }
 424
 425 static int acpi_device_install_notify_handler(struct acpi_device *device)
 426 {
 427         acpi_status status;
 428
 429         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 430                 status =
 431                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 432                                                      acpi_device_notify_fixed,
 433                                                      device);
 434         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 435                 status =
 436                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 437                                                      acpi_device_notify_fixed,
 438                                                      device);
 439         else
 440                 status = acpi_install_notify_handler(device->handle,
 441                                                      ACPI_DEVICE_NOTIFY,
 442                                                      acpi_device_notify,
 443                                                      device);
 444
 445         if (ACPI_FAILURE(status))
 446                 return -EINVAL;
 447         return 0;
 448 }
 449
 450 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 451 {
 452         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 453                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 454                                                 acpi_device_notify_fixed);
 455         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 456                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 457                                                 acpi_device_notify_fixed);
 458         else
 459                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 460                                            acpi_device_notify);
 461 }
 462
 463 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
 464 static int acpi_start_single_object(struct acpi_device *);
 465 static int acpi_device_probe(struct device * dev)
 466 {
 467         struct acpi_device *acpi_dev = to_acpi_device(dev);
 468         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 469         int ret;
 470
 471         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
 472         if (!ret) {
 473                 if (acpi_dev->bus_ops.acpi_op_start)
 474                         acpi_start_single_object(acpi_dev);
 475
 476                 if (acpi_drv->ops.notify) {
 477                         ret = acpi_device_install_notify_handler(acpi_dev);
 478                         if (ret) {
 479                                 if (acpi_drv->ops.remove)
 480                                         acpi_drv->ops.remove(acpi_dev,
 481                                                      acpi_dev->removal_type);
 482                                 return ret;
 483                         }
 484                 }
 485
 486                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 487                         "Found driver [%s] for device [%s]\n",
 488                         acpi_drv->name, acpi_dev->pnp.bus_id));
 489                 get_device(dev);
 490         }
 491         return ret;
 492 }
 493
 494 static int acpi_device_remove(struct device * dev)
 495 {
 496         struct acpi_device *acpi_dev = to_acpi_device(dev);
 497         struct acpi_driver *acpi_drv = acpi_dev->driver;
 498
 499         if (acpi_drv) {
 500                 if (acpi_drv->ops.notify)
 501                         acpi_device_remove_notify_handler(acpi_dev);
 502                 if (acpi_drv->ops.remove)
 503                         acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
 504         }
 505         acpi_dev->driver = NULL;
 506         acpi_dev->driver_data = NULL;
 507
 508         put_device(dev);
 509         return 0;
 510 }
 511
 512 struct bus_type acpi_bus_type = {
 513         .name           = "acpi",
 514         .match          = acpi_bus_match,
 515         .probe          = acpi_device_probe,
 516         .remove         = acpi_device_remove,
 517         .uevent         = acpi_device_uevent,
 518 };
 519
 520 static int acpi_device_register(struct acpi_device *device)
 521 {
 522         int result;
 523         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 524         int found = 0;
 525
 526         /*
 527          * Linkage
 528          * -------
 529          * Link this device to its parent and siblings.
 530          */
 531         INIT_LIST_HEAD(&device->children);
 532         INIT_LIST_HEAD(&device->node);
 533         INIT_LIST_HEAD(&device->wakeup_list);
 534         INIT_LIST_HEAD(&device->physical_node_list);
 535         mutex_init(&device->physical_node_lock);
 536
 537         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 538         if (!new_bus_id) {
 539                 printk(KERN_ERR PREFIX "Memory allocation error\n");
 540                 return -ENOMEM;
 541         }
 542
 543         mutex_lock(&acpi_device_lock);
 544         /*
 545          * Find suitable bus_id and instance number in acpi_bus_id_list
 546          * If failed, create one and link it into acpi_bus_id_list
 547          */
 548         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 549                 if (!strcmp(acpi_device_bus_id->bus_id,
 550                             acpi_device_hid(device))) {
 551                         acpi_device_bus_id->instance_no++;
 552                         found = 1;
 553                         kfree(new_bus_id);
 554                         break;
 555                 }
 556         }
 557         if (!found) {
 558                 acpi_device_bus_id = new_bus_id;
 559                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
 560                 acpi_device_bus_id->instance_no = 0;
 561                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 562         }
 563         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 564
 565         if (device->parent)
 566                 list_add_tail(&device->node, &device->parent->children);
 567
 568         if (device->wakeup.flags.valid)
 569                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 570         mutex_unlock(&acpi_device_lock);
 571
 572         if (device->parent)
 573                 device->dev.parent = &device->parent->dev;
 574         device->dev.bus = &acpi_bus_type;
 575         device->dev.release = &acpi_device_release;
 576         result = device_register(&device->dev);
 577         if (result) {
 578                 dev_err(&device->dev, "Error registering device\n");
 579                 goto end;
 580         }
 581
 582         result = acpi_device_setup_files(device);
 583         if (result)
 584                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 585                        dev_name(&device->dev));
 586
 587         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
 588         return 0;
 589 end:
 590         mutex_lock(&acpi_device_lock);
 591         if (device->parent)
 592                 list_del(&device->node);
 593         list_del(&device->wakeup_list);
 594         mutex_unlock(&acpi_device_lock);
 595         return result;
 596 }
 597
 598 static void acpi_device_unregister(struct acpi_device *device, int type)
 599 {
 600         mutex_lock(&acpi_device_lock);
 601         if (device->parent)
 602                 list_del(&device->node);
 603
 604         list_del(&device->wakeup_list);
 605         mutex_unlock(&acpi_device_lock);
 606
 607         acpi_detach_data(device->handle, acpi_bus_data_handler);
 608
 609         acpi_device_remove_files(device);
 610         device_unregister(&device->dev);
 611 }
 612
 613 /* --------------------------------------------------------------------------
 614                                  Driver Management
 615    -------------------------------------------------------------------------- */
 616 /**
 617  * acpi_bus_driver_init - add a device to a driver
 618  * @device: the device to add and initialize
 619  * @driver: driver for the device
 620  *
 621  * Used to initialize a device via its device driver.  Called whenever a
 622  * driver is bound to a device.  Invokes the driver's add() ops.
 623  */
 624 static int
 625 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
 626 {
 627         int result = 0;
 628
 629         if (!device || !driver)
 630                 return -EINVAL;
 631
 632         if (!driver->ops.add)
 633                 return -ENOSYS;
 634
 635         result = driver->ops.add(device);
 636         if (result) {
 637                 device->driver = NULL;
 638                 device->driver_data = NULL;
 639                 return result;
 640         }
 641
 642         device->driver = driver;
 643
 644         /*
 645          * TBD - Configuration Management: Assign resources to device based
 646          * upon possible configuration and currently allocated resources.
 647          */
 648
 649         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 650                           "Driver successfully bound to device\n"));
 651         return 0;
 652 }
 653
 654 static int acpi_start_single_object(struct acpi_device *device)
 655 {
 656         int result = 0;
 657         struct acpi_driver *driver;
 658
 659
 660         if (!(driver = device->driver))
 661                 return 0;
 662
 663         if (driver->ops.start) {
 664                 result = driver->ops.start(device);
 665                 if (result && driver->ops.remove)
 666                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
 667         }
 668
 669         return result;
 670 }
 671
 672 /**
 673  * acpi_bus_register_driver - register a driver with the ACPI bus
 674  * @driver: driver being registered
 675  *
 676  * Registers a driver with the ACPI bus.  Searches the namespace for all
 677  * devices that match the driver's criteria and binds.  Returns zero for
 678  * success or a negative error status for failure.
 679  */
 680 int acpi_bus_register_driver(struct acpi_driver *driver)
 681 {
 682         int ret;
 683
 684         if (acpi_disabled)
 685                 return -ENODEV;
 686         driver->drv.name = driver->name;
 687         driver->drv.bus = &acpi_bus_type;
 688         driver->drv.owner = driver->owner;
 689
 690         ret = driver_register(&driver->drv);
 691         return ret;
 692 }
 693
 694 EXPORT_SYMBOL(acpi_bus_register_driver);
 695
 696 /**
 697  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
 698  * @driver: driver to unregister
 699  *
 700  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
 701  * devices that match the driver's criteria and unbinds.
 702  */
 703 void acpi_bus_unregister_driver(struct acpi_driver *driver)
 704 {
 705         driver_unregister(&driver->drv);
 706 }
 707
 708 EXPORT_SYMBOL(acpi_bus_unregister_driver);
 709
 710 /* --------------------------------------------------------------------------
 711                                  Device Enumeration
 712    -------------------------------------------------------------------------- */
 713 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
 714 {
 715         acpi_status status;
 716         int ret;
 717         struct acpi_device *device;
 718
 719         /*
 720          * Fixed hardware devices do not appear in the namespace and do not
 721          * have handles, but we fabricate acpi_devices for them, so we have
 722          * to deal with them specially.
 723          */
 724         if (handle == NULL)
 725                 return acpi_root;
 726
 727         do {
 728                 status = acpi_get_parent(handle, &handle);
 729                 if (status == AE_NULL_ENTRY)
 730                         return NULL;
 731                 if (ACPI_FAILURE(status))
 732                         return acpi_root;
 733
 734                 ret = acpi_bus_get_device(handle, &device);
 735                 if (ret == 0)
 736                         return device;
 737         } while (1);
 738 }
 739
 740 acpi_status
 741 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 742 {
 743         acpi_status status;
 744         acpi_handle tmp;
 745         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 746         union acpi_object *obj;
 747
 748         status = acpi_get_handle(handle, "_EJD", &tmp);
 749         if (ACPI_FAILURE(status))
 750                 return status;
 751
 752         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 753         if (ACPI_SUCCESS(status)) {
 754                 obj = buffer.pointer;
 755                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 756                                          ejd);
 757                 kfree(buffer.pointer);
 758         }
 759         return status;
 760 }
 761 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 762
 763 void acpi_bus_data_handler(acpi_handle handle, void *context)
 764 {
 765
 766         /* TBD */
 767
 768         return;
 769 }
 770
 771 static int acpi_bus_get_perf_flags(struct acpi_device *device)
 772 {
 773         device->performance.state = ACPI_STATE_UNKNOWN;
 774         return 0;
 775 }
 776
 777 static acpi_status
 778 acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
 779                                              struct acpi_device_wakeup *wakeup)
 780 {
 781         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 782         union acpi_object *package = NULL;
 783         union acpi_object *element = NULL;
 784         acpi_status status;
 785         int i = 0;
 786
 787         if (!wakeup)
 788                 return AE_BAD_PARAMETER;
 789
 790         /* _PRW */
 791         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
 792         if (ACPI_FAILURE(status)) {
 793                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 794                 return status;
 795         }
 796
 797         package = (union acpi_object *)buffer.pointer;
 798
 799         if (!package || (package->package.count < 2)) {
 800                 status = AE_BAD_DATA;
 801                 goto out;
 802         }
 803
 804         element = &(package->package.elements[0]);
 805         if (!element) {
 806                 status = AE_BAD_DATA;
 807                 goto out;
 808         }
 809         if (element->type == ACPI_TYPE_PACKAGE) {
 810                 if ((element->package.count < 2) ||
 811                     (element->package.elements[0].type !=
 812                      ACPI_TYPE_LOCAL_REFERENCE)
 813                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER)) {
 814                         status = AE_BAD_DATA;
 815                         goto out;
 816                 }
 817                 wakeup->gpe_device =
 818                     element->package.elements[0].reference.handle;
 819                 wakeup->gpe_number =
 820                     (u32) element->package.elements[1].integer.value;
 821         } else if (element->type == ACPI_TYPE_INTEGER) {
 822                 wakeup->gpe_device = NULL;
 823                 wakeup->gpe_number = element->integer.value;
 824         } else {
 825                 status = AE_BAD_DATA;
 826                 goto out;
 827         }
 828
 829         element = &(package->package.elements[1]);
 830         if (element->type != ACPI_TYPE_INTEGER) {
 831                 status = AE_BAD_DATA;
 832                 goto out;
 833         }
 834         wakeup->sleep_state = element->integer.value;
 835
 836         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
 837                 status = AE_NO_MEMORY;
 838                 goto out;
 839         }
 840         wakeup->resources.count = package->package.count - 2;
 841         for (i = 0; i < wakeup->resources.count; i++) {
 842                 element = &(package->package.elements[i + 2]);
 843                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
 844                         status = AE_BAD_DATA;
 845                         goto out;
 846                 }
 847
 848                 wakeup->resources.handles[i] = element->reference.handle;
 849         }
 850
 851         acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
 852
 853  out:
 854         kfree(buffer.pointer);
 855
 856         return status;
 857 }
 858
 859 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
 860 {
 861         struct acpi_device_id button_device_ids[] = {
 862                 {"PNP0C0D", 0},
 863                 {"PNP0C0C", 0},
 864                 {"PNP0C0E", 0},
 865                 {"", 0},
 866         };
 867         acpi_status status;
 868         acpi_event_status event_status;
 869
 870         device->wakeup.flags.notifier_present = 0;
 871
 872         /* Power button, Lid switch always enable wakeup */
 873         if (!acpi_match_device_ids(device, button_device_ids)) {
 874                 device->wakeup.flags.run_wake = 1;
 875                 device_set_wakeup_capable(&device->dev, true);
 876                 return;
 877         }
 878
 879         status = acpi_get_gpe_status(device->wakeup.gpe_device,
 880                                         device->wakeup.gpe_number,
 881                                                 &event_status);
 882         if (status == AE_OK)
 883                 device->wakeup.flags.run_wake =
 884                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
 885 }
 886
 887 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 888 {
 889         acpi_handle temp;
 890         acpi_status status = 0;
 891         int psw_error;
 892
 893         /* Presence of _PRW indicates wake capable */
 894         status = acpi_get_handle(device->handle, "_PRW", &temp);
 895         if (ACPI_FAILURE(status))
 896                 return;
 897
 898         status = acpi_bus_extract_wakeup_device_power_package(device->handle,
 899                                                               &device->wakeup);
 900         if (ACPI_FAILURE(status)) {
 901                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
 902                 return;
 903         }
 904
 905         device->wakeup.flags.valid = 1;
 906         device->wakeup.prepare_count = 0;
 907         acpi_bus_set_run_wake_flags(device);
 908         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
 909          * system for the ACPI device with the _PRW object.
 910          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 911          * So it is necessary to call _DSW object first. Only when it is not
 912          * present will the _PSW object used.
 913          */
 914         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
 915         if (psw_error)
 916                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 917                                 "error in _DSW or _PSW evaluation\n"));
 918 }
 919
 920 static void acpi_bus_add_power_resource(acpi_handle handle);
 921
 922 static int acpi_bus_get_power_flags(struct acpi_device *device)
 923 {
 924         acpi_status status = 0;
 925         acpi_handle handle = NULL;
 926         u32 i = 0;
 927
 928
 929         /*
 930          * Power Management Flags
 931          */
 932         status = acpi_get_handle(device->handle, "_PSC", &handle);
 933         if (ACPI_SUCCESS(status))
 934                 device->power.flags.explicit_get = 1;
 935         status = acpi_get_handle(device->handle, "_IRC", &handle);
 936         if (ACPI_SUCCESS(status))
 937                 device->power.flags.inrush_current = 1;
 938
 939         /*
 940          * Enumerate supported power management states
 941          */
 942         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 943                 struct acpi_device_power_state *ps = &device->power.states[i];
 944                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
 945
 946                 /* Evaluate "_PRx" to se if power resources are referenced */
 947                 acpi_evaluate_reference(device->handle, object_name, NULL,
 948                                         &ps->resources);
 949                 if (ps->resources.count) {
 950                         int j;
 951
 952                         device->power.flags.power_resources = 1;
 953                         for (j = 0; j < ps->resources.count; j++)
 954                                 acpi_bus_add_power_resource(ps->resources.handles[j]);
 955                 }
 956
 957                 /* Evaluate "_PSx" to see if we can do explicit sets */
 958                 object_name[2] = 'S';
 959                 status = acpi_get_handle(device->handle, object_name, &handle);
 960                 if (ACPI_SUCCESS(status))
 961                         ps->flags.explicit_set = 1;
 962
 963                 /*
 964                  * State is valid if there are means to put the device into it.
 965                  * D3hot is only valid if _PR3 present.
 966                  */
 967                 if (ps->resources.count ||
 968                     (ps->flags.explicit_set && i < ACPI_STATE_D3_HOT))
 969                         ps->flags.valid = 1;
 970
 971                 ps->power = -1; /* Unknown - driver assigned */
 972                 ps->latency = -1;       /* Unknown - driver assigned */
 973         }
 974
 975         /* Set defaults for D0 and D3 states (always valid) */
 976         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 977         device->power.states[ACPI_STATE_D0].power = 100;
 978         device->power.states[ACPI_STATE_D3].flags.valid = 1;
 979         device->power.states[ACPI_STATE_D3].power = 0;
 980
 981         /* Set D3cold's explicit_set flag if _PS3 exists. */
 982         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
 983                 device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
 984
 985         acpi_bus_init_power(device);
 986
 987         return 0;
 988 }
 989
 990 static int acpi_bus_get_flags(struct acpi_device *device)
 991 {
 992         acpi_status status = AE_OK;
 993         acpi_handle temp = NULL;
 994
 995
 996         /* Presence of _STA indicates 'dynamic_status' */
 997         status = acpi_get_handle(device->handle, "_STA", &temp);
 998         if (ACPI_SUCCESS(status))
 999                 device->flags.dynamic_status = 1;
1000
1001         /* Presence of _RMV indicates 'removable' */
1002         status = acpi_get_handle(device->handle, "_RMV", &temp);
1003         if (ACPI_SUCCESS(status))
1004                 device->flags.removable = 1;
1005
1006         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1007         status = acpi_get_handle(device->handle, "_EJD", &temp);
1008         if (ACPI_SUCCESS(status))
1009                 device->flags.ejectable = 1;
1010         else {
1011                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
1012                 if (ACPI_SUCCESS(status))
1013                         device->flags.ejectable = 1;
1014         }
1015
1016         /* Presence of _LCK indicates 'lockable' */
1017         status = acpi_get_handle(device->handle, "_LCK", &temp);
1018         if (ACPI_SUCCESS(status))
1019                 device->flags.lockable = 1;
1020
1021         /* Power resources cannot be power manageable. */
1022         if (device->device_type == ACPI_BUS_TYPE_POWER)
1023                 return 0;
1024
1025         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1026         status = acpi_get_handle(device->handle, "_PS0", &temp);
1027         if (ACPI_FAILURE(status))
1028                 status = acpi_get_handle(device->handle, "_PR0", &temp);
1029         if (ACPI_SUCCESS(status))
1030                 device->flags.power_manageable = 1;
1031
1032         /* TBD: Performance management */
1033
1034         return 0;
1035 }
1036
1037 static void acpi_device_get_busid(struct acpi_device *device)
1038 {
1039         char bus_id[5] = { '?', 0 };
1040         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1041         int i = 0;
1042
1043         /*
1044          * Bus ID
1045          * ------
1046          * The device's Bus ID is simply the object name.
1047          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1048          */
1049         if (ACPI_IS_ROOT_DEVICE(device)) {
1050                 strcpy(device->pnp.bus_id, "ACPI");
1051                 return;
1052         }
1053
1054         switch (device->device_type) {
1055         case ACPI_BUS_TYPE_POWER_BUTTON:
1056                 strcpy(device->pnp.bus_id, "PWRF");
1057                 break;
1058         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1059                 strcpy(device->pnp.bus_id, "SLPF");
1060                 break;
1061         default:
1062                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1063                 /* Clean up trailing underscores (if any) */
1064                 for (i = 3; i > 1; i--) {
1065                         if (bus_id[i] == '_')
1066                                 bus_id[i] = '\0';
1067                         else
1068                                 break;
1069                 }
1070                 strcpy(device->pnp.bus_id, bus_id);
1071                 break;
1072         }
1073 }
1074
1075 /*
1076  * acpi_bay_match - see if a device is an ejectable driver bay
1077  *
1078  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1079  * then we can safely call it an ejectable drive bay
1080  */
1081 static int acpi_bay_match(struct acpi_device *device){
1082         acpi_status status;
1083         acpi_handle handle;
1084         acpi_handle tmp;
1085         acpi_handle phandle;
1086
1087         handle = device->handle;
1088
1089         status = acpi_get_handle(handle, "_EJ0", &tmp);
1090         if (ACPI_FAILURE(status))
1091                 return -ENODEV;
1092
1093         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
1094                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
1095                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
1096                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
1097                 return 0;
1098
1099         if (acpi_get_parent(handle, &phandle))
1100                 return -ENODEV;
1101
1102         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
1103                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
1104                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
1105                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
1106                 return 0;
1107
1108         return -ENODEV;
1109 }
1110
1111 /*
1112  * acpi_dock_match - see if a device has a _DCK method
1113  */
1114 static int acpi_dock_match(struct acpi_device *device)
1115 {
1116         acpi_handle tmp;
1117         return acpi_get_handle(device->handle, "_DCK", &tmp);
1118 }
1119
1120 const char *acpi_device_hid(struct acpi_device *device)
1121 {
1122         struct acpi_hardware_id *hid;
1123
1124         if (list_empty(&device->pnp.ids))
1125                 return dummy_hid;
1126
1127         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1128         return hid->id;
1129 }
1130 EXPORT_SYMBOL(acpi_device_hid);
1131
1132 static void acpi_add_id(struct acpi_device *device, const char *dev_id)
1133 {
1134         struct acpi_hardware_id *id;
1135
1136         id = kmalloc(sizeof(*id), GFP_KERNEL);
1137         if (!id)
1138                 return;
1139
1140         id->id = kstrdup(dev_id, GFP_KERNEL);
1141         if (!id->id) {
1142                 kfree(id);
1143                 return;
1144         }
1145
1146         list_add_tail(&id->list, &device->pnp.ids);
1147 }
1148
1149 /*
1150  * Old IBM workstations have a DSDT bug wherein the SMBus object
1151  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1152  * prefix.  Work around this.
1153  */
1154 static int acpi_ibm_smbus_match(struct acpi_device *device)
1155 {
1156         acpi_handle h_dummy;
1157         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1158         int result;
1159
1160         if (!dmi_name_in_vendors("IBM"))
1161                 return -ENODEV;
1162
1163         /* Look for SMBS object */
1164         result = acpi_get_name(device->handle, ACPI_SINGLE_NAME, &path);
1165         if (result)
1166                 return result;
1167
1168         if (strcmp("SMBS", path.pointer)) {
1169                 result = -ENODEV;
1170                 goto out;
1171         }
1172
1173         /* Does it have the necessary (but misnamed) methods? */
1174         result = -ENODEV;
1175         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "SBI", &h_dummy)) &&
1176             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBR", &h_dummy)) &&
1177             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBW", &h_dummy)))
1178                 result = 0;
1179 out:
1180         kfree(path.pointer);
1181         return result;
1182 }
1183
1184 static void acpi_device_set_id(struct acpi_device *device)
1185 {
1186         acpi_status status;
1187         struct acpi_device_info *info;
1188         struct acpica_device_id_list *cid_list;
1189         int i;
1190
1191         switch (device->device_type) {
1192         case ACPI_BUS_TYPE_DEVICE:
1193                 if (ACPI_IS_ROOT_DEVICE(device)) {
1194                         acpi_add_id(device, ACPI_SYSTEM_HID);
1195                         break;
1196                 }
1197
1198                 status = acpi_get_object_info(device->handle, &info);
1199                 if (ACPI_FAILURE(status)) {
1200                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1201                         return;
1202                 }
1203
1204                 if (info->valid & ACPI_VALID_HID)
1205                         acpi_add_id(device, info->hardware_id.string);
1206                 if (info->valid & ACPI_VALID_CID) {
1207                         cid_list = &info->compatible_id_list;
1208                         for (i = 0; i < cid_list->count; i++)
1209                                 acpi_add_id(device, cid_list->ids[i].string);
1210                 }
1211                 if (info->valid & ACPI_VALID_ADR) {
1212                         device->pnp.bus_address = info->address;
1213                         device->flags.bus_address = 1;
1214                 }
1215
1216                 kfree(info);
1217
1218                 /*
1219                  * Some devices don't reliably have _HIDs & _CIDs, so add
1220                  * synthetic HIDs to make sure drivers can find them.
1221                  */
1222                 if (acpi_is_video_device(device))
1223                         acpi_add_id(device, ACPI_VIDEO_HID);
1224                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1225                         acpi_add_id(device, ACPI_BAY_HID);
1226                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1227                         acpi_add_id(device, ACPI_DOCK_HID);
1228                 else if (!acpi_ibm_smbus_match(device))
1229                         acpi_add_id(device, ACPI_SMBUS_IBM_HID);
1230                 else if (!acpi_device_hid(device) &&
1231                          ACPI_IS_ROOT_DEVICE(device->parent)) {
1232                         acpi_add_id(device, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1233                         strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1234                         strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1235                 }
1236
1237                 break;
1238         case ACPI_BUS_TYPE_POWER:
1239                 acpi_add_id(device, ACPI_POWER_HID);
1240                 break;
1241         case ACPI_BUS_TYPE_PROCESSOR:
1242                 acpi_add_id(device, ACPI_PROCESSOR_OBJECT_HID);
1243                 break;
1244         case ACPI_BUS_TYPE_THERMAL:
1245                 acpi_add_id(device, ACPI_THERMAL_HID);
1246                 break;
1247         case ACPI_BUS_TYPE_POWER_BUTTON:
1248                 acpi_add_id(device, ACPI_BUTTON_HID_POWERF);
1249                 break;
1250         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1251                 acpi_add_id(device, ACPI_BUTTON_HID_SLEEPF);
1252                 break;
1253         }
1254 }
1255
1256 static int acpi_device_set_context(struct acpi_device *device)
1257 {
1258         acpi_status status;
1259
1260         /*
1261          * Context
1262          * -------
1263          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1264          * resolutions from handle->device very efficient.  Fixed hardware
1265          * devices have no handles, so we skip them.
1266          */
1267         if (!device->handle)
1268                 return 0;
1269
1270         status = acpi_attach_data(device->handle,
1271                                   acpi_bus_data_handler, device);
1272         if (ACPI_SUCCESS(status))
1273                 return 0;
1274
1275         printk(KERN_ERR PREFIX "Error attaching device data\n");
1276         return -ENODEV;
1277 }
1278
1279 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1280 {
1281         if (!dev)
1282                 return -EINVAL;
1283
1284         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1285         device_release_driver(&dev->dev);
1286
1287         if (!rmdevice)
1288                 return 0;
1289
1290         /*
1291          * unbind _ADR-Based Devices when hot removal
1292          */
1293         if (dev->flags.bus_address) {
1294                 if ((dev->parent) && (dev->parent->ops.unbind))
1295                         dev->parent->ops.unbind(dev);
1296         }
1297         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1298
1299         return 0;
1300 }
1301
1302 static int acpi_add_single_object(struct acpi_device **child,
1303                                   acpi_handle handle, int type,
1304                                   unsigned long long sta,
1305                                   struct acpi_bus_ops *ops)
1306 {
1307         int result;
1308         struct acpi_device *device;
1309         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1310
1311         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1312         if (!device) {
1313                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1314                 return -ENOMEM;
1315         }
1316
1317         INIT_LIST_HEAD(&device->pnp.ids);
1318         device->device_type = type;
1319         device->handle = handle;
1320         device->parent = acpi_bus_get_parent(handle);
1321         device->bus_ops = *ops; /* workround for not call .start */
1322         STRUCT_TO_INT(device->status) = sta;
1323
1324         acpi_device_get_busid(device);
1325
1326         /*
1327          * Flags
1328          * -----
1329          * Note that we only look for object handles -- cannot evaluate objects
1330          * until we know the device is present and properly initialized.
1331          */
1332         result = acpi_bus_get_flags(device);
1333         if (result)
1334                 goto end;
1335
1336         /*
1337          * Initialize Device
1338          * -----------------
1339          * TBD: Synch with Core's enumeration/initialization process.
1340          */
1341         acpi_device_set_id(device);
1342
1343         /*
1344          * Power Management
1345          * ----------------
1346          */
1347         if (device->flags.power_manageable) {
1348                 result = acpi_bus_get_power_flags(device);
1349                 if (result)
1350                         goto end;
1351         }
1352
1353         /*
1354          * Wakeup device management
1355          *-----------------------
1356          */
1357         acpi_bus_get_wakeup_device_flags(device);
1358
1359         /*
1360          * Performance Management
1361          * ----------------------
1362          */
1363         if (device->flags.performance_manageable) {
1364                 result = acpi_bus_get_perf_flags(device);
1365                 if (result)
1366                         goto end;
1367         }
1368
1369         if ((result = acpi_device_set_context(device)))
1370                 goto end;
1371
1372         result = acpi_device_register(device);
1373
1374         /*
1375          * Bind _ADR-Based Devices when hot add
1376          */
1377         if (device->flags.bus_address) {
1378                 if (device->parent && device->parent->ops.bind)
1379                         device->parent->ops.bind(device);
1380         }
1381
1382 end:
1383         if (!result) {
1384                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1385                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1386                         "Adding %s [%s] parent %s\n", dev_name(&device->dev),
1387                          (char *) buffer.pointer,
1388                          device->parent ? dev_name(&device->parent->dev) :
1389                                           "(null)"));
1390                 kfree(buffer.pointer);
1391                 *child = device;
1392         } else
1393                 acpi_device_release(&device->dev);
1394
1395         return result;
1396 }
1397
1398 #define ACPI_STA_DEFAULT (ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED | \
1399                           ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING)
1400
1401 static void acpi_bus_add_power_resource(acpi_handle handle)
1402 {
1403         struct acpi_bus_ops ops = {
1404                 .acpi_op_add = 1,
1405                 .acpi_op_start = 1,
1406         };
1407         struct acpi_device *device = NULL;
1408
1409         acpi_bus_get_device(handle, &device);
1410         if (!device)
1411                 acpi_add_single_object(&device, handle, ACPI_BUS_TYPE_POWER,
1412                                         ACPI_STA_DEFAULT, &ops);
1413 }
1414
1415 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1416                                     unsigned long long *sta)
1417 {
1418         acpi_status status;
1419         acpi_object_type acpi_type;
1420
1421         status = acpi_get_type(handle, &acpi_type);
1422         if (ACPI_FAILURE(status))
1423                 return -ENODEV;
1424
1425         switch (acpi_type) {
1426         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1427         case ACPI_TYPE_DEVICE:
1428                 *type = ACPI_BUS_TYPE_DEVICE;
1429                 status = acpi_bus_get_status_handle(handle, sta);
1430                 if (ACPI_FAILURE(status))
1431                         return -ENODEV;
1432                 break;
1433         case ACPI_TYPE_PROCESSOR:
1434                 *type = ACPI_BUS_TYPE_PROCESSOR;
1435                 status = acpi_bus_get_status_handle(handle, sta);
1436                 if (ACPI_FAILURE(status))
1437                         return -ENODEV;
1438                 break;
1439         case ACPI_TYPE_THERMAL:
1440                 *type = ACPI_BUS_TYPE_THERMAL;
1441                 *sta = ACPI_STA_DEFAULT;
1442                 break;
1443         case ACPI_TYPE_POWER:
1444                 *type = ACPI_BUS_TYPE_POWER;
1445                 *sta = ACPI_STA_DEFAULT;
1446                 break;
1447         default:
1448                 return -ENODEV;
1449         }
1450
1451         return 0;
1452 }
1453
1454 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl,
1455                                       void *context, void **return_value)
1456 {
1457         struct acpi_bus_ops *ops = context;
1458         int type;
1459         unsigned long long sta;
1460         struct acpi_device *device;
1461         acpi_status status;
1462         int result;
1463
1464         result = acpi_bus_type_and_status(handle, &type, &sta);
1465         if (result)
1466                 return AE_OK;
1467
1468         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1469             !(sta & ACPI_STA_DEVICE_FUNCTIONING)) {
1470                 struct acpi_device_wakeup wakeup;
1471                 acpi_handle temp;
1472
1473                 status = acpi_get_handle(handle, "_PRW", &temp);
1474                 if (ACPI_SUCCESS(status))
1475                         acpi_bus_extract_wakeup_device_power_package(handle,
1476                                                                      &wakeup);
1477                 return AE_CTRL_DEPTH;
1478         }
1479
1480         /*
1481          * We may already have an acpi_device from a previous enumeration.  If
1482          * so, we needn't add it again, but we may still have to start it.
1483          */
1484         device = NULL;
1485         acpi_bus_get_device(handle, &device);
1486         if (ops->acpi_op_add && !device)
1487                 acpi_add_single_object(&device, handle, type, sta, ops);
1488
1489         if (!device)
1490                 return AE_CTRL_DEPTH;
1491
1492         if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1493                 status = acpi_start_single_object(device);
1494                 if (ACPI_FAILURE(status))
1495                         return AE_CTRL_DEPTH;
1496         }
1497
1498         if (!*return_value)
1499                 *return_value = device;
1500         return AE_OK;
1501 }
1502
1503 static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops,
1504                          struct acpi_device **child)
1505 {
1506         acpi_status status;
1507         void *device = NULL;
1508
1509         status = acpi_bus_check_add(handle, 0, ops, &device);
1510         if (ACPI_SUCCESS(status))
1511                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1512                                     acpi_bus_check_add, NULL, ops, &device);
1513
1514         if (child)
1515                 *child = device;
1516
1517         if (device)
1518                 return 0;
1519         else
1520                 return -ENODEV;
1521 }
1522
1523 /*
1524  * acpi_bus_add and acpi_bus_start
1525  *
1526  * scan a given ACPI tree and (probably recently hot-plugged)
1527  * create and add or starts found devices.
1528  *
1529  * If no devices were found -ENODEV is returned which does not
1530  * mean that this is a real error, there just have been no suitable
1531  * ACPI objects in the table trunk from which the kernel could create
1532  * a device and add/start an appropriate driver.
1533  */
1534
1535 int
1536 acpi_bus_add(struct acpi_device **child,
1537              struct acpi_device *parent, acpi_handle handle, int type)
1538 {
1539         struct acpi_bus_ops ops;
1540
1541         memset(&ops, 0, sizeof(ops));
1542         ops.acpi_op_add = 1;
1543
1544         return acpi_bus_scan(handle, &ops, child);
1545 }
1546 EXPORT_SYMBOL(acpi_bus_add);
1547
1548 int acpi_bus_start(struct acpi_device *device)
1549 {
1550         struct acpi_bus_ops ops;
1551         int result;
1552
1553         if (!device)
1554                 return -EINVAL;
1555
1556         memset(&ops, 0, sizeof(ops));
1557         ops.acpi_op_start = 1;
1558
1559         result = acpi_bus_scan(device->handle, &ops, NULL);
1560
1561         acpi_update_all_gpes();
1562
1563         return result;
1564 }
1565 EXPORT_SYMBOL(acpi_bus_start);
1566
1567 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1568 {
1569         acpi_status status;
1570         struct acpi_device *parent, *child;
1571         acpi_handle phandle, chandle;
1572         acpi_object_type type;
1573         u32 level = 1;
1574         int err = 0;
1575
1576         parent = start;
1577         phandle = start->handle;
1578         child = chandle = NULL;
1579
1580         while ((level > 0) && parent && (!err)) {
1581                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1582                                               chandle, &chandle);
1583
1584                 /*
1585                  * If this scope is exhausted then move our way back up.
1586                  */
1587                 if (ACPI_FAILURE(status)) {
1588                         level--;
1589                         chandle = phandle;
1590                         acpi_get_parent(phandle, &phandle);
1591                         child = parent;
1592                         parent = parent->parent;
1593
1594                         if (level == 0)
1595                                 err = acpi_bus_remove(child, rmdevice);
1596                         else
1597                                 err = acpi_bus_remove(child, 1);
1598
1599                         continue;
1600                 }
1601
1602                 status = acpi_get_type(chandle, &type);
1603                 if (ACPI_FAILURE(status)) {
1604                         continue;
1605                 }
1606                 /*
1607                  * If there is a device corresponding to chandle then
1608                  * parse it (depth-first).
1609                  */
1610                 if (acpi_bus_get_device(chandle, &child) == 0) {
1611                         level++;
1612                         phandle = chandle;
1613                         chandle = NULL;
1614                         parent = child;
1615                 }
1616                 continue;
1617         }
1618         return err;
1619 }
1620 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1621
1622 static int acpi_bus_scan_fixed(void)
1623 {
1624         int result = 0;
1625         struct acpi_device *device = NULL;
1626         struct acpi_bus_ops ops;
1627
1628         memset(&ops, 0, sizeof(ops));
1629         ops.acpi_op_add = 1;
1630         ops.acpi_op_start = 1;
1631
1632         /*
1633          * Enumerate all fixed-feature devices.
1634          */
1635         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1636                 result = acpi_add_single_object(&device, NULL,
1637                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1638                                                 ACPI_STA_DEFAULT,
1639                                                 &ops);
1640                 device_init_wakeup(&device->dev, true);
1641         }
1642
1643         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1644                 result = acpi_add_single_object(&device, NULL,
1645                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1646                                                 ACPI_STA_DEFAULT,
1647                                                 &ops);
1648         }
1649
1650         return result;
1651 }
1652
1653 int __init acpi_scan_init(void)
1654 {
1655         int result;
1656         struct acpi_bus_ops ops;
1657
1658         memset(&ops, 0, sizeof(ops));
1659         ops.acpi_op_add = 1;
1660         ops.acpi_op_start = 1;
1661
1662         result = bus_register(&acpi_bus_type);
1663         if (result) {
1664                 /* We don't want to quit even if we failed to add suspend/resume */
1665                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1666         }
1667
1668         acpi_power_init();
1669
1670         /*
1671          * Enumerate devices in the ACPI namespace.
1672          */
1673         result = acpi_bus_scan(ACPI_ROOT_OBJECT, &ops, &acpi_root);
1674
1675         if (!result)
1676                 result = acpi_bus_scan_fixed();
1677
1678         if (result)
1679                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1680         else
1681                 acpi_update_all_gpes();
1682
1683         return result;
1684 }