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/acpi.h>
   8
   9 #include <acpi/acpi_drivers.h>
  10 #include <acpi/acinterp.h>      /* for acpi_ex_eisa_id_to_string() */
  11
  12
  13 #define _COMPONENT              ACPI_BUS_COMPONENT
  14 ACPI_MODULE_NAME                ("scan")
  15
  16 #define STRUCT_TO_INT(s)        (*((int*)&s))
  17
  18 extern struct acpi_device               *acpi_root;
  19
  20
  21 #define ACPI_BUS_CLASS                  "system_bus"
  22 #define ACPI_BUS_HID                    "ACPI_BUS"
  23 #define ACPI_BUS_DRIVER_NAME            "ACPI Bus Driver"
  24 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  25
  26 static LIST_HEAD(acpi_device_list);
  27 DEFINE_SPINLOCK(acpi_device_lock);
  28 LIST_HEAD(acpi_wakeup_device_list);
  29
  30 static int
  31 acpi_bus_trim(struct acpi_device        *start,
  32                 int rmdevice);
  33
  34 static void acpi_device_release(struct kobject * kobj)
  35 {
  36         struct acpi_device * dev = container_of(kobj,struct acpi_device,kobj);
  37         if (dev->pnp.cid_list)
  38                 kfree(dev->pnp.cid_list);
  39         kfree(dev);
  40 }
  41
  42 struct acpi_device_attribute {
  43         struct attribute attr;
  44         ssize_t (*show)(struct acpi_device *, char *);
  45         ssize_t (*store)(struct acpi_device *, const char *, size_t);
  46 };
  47
  48 typedef void acpi_device_sysfs_files(struct kobject *,
  49                                 const struct attribute *);
  50
  51 static void setup_sys_fs_device_files(struct acpi_device *dev,
  52                 acpi_device_sysfs_files *func);
  53
  54 #define create_sysfs_device_files(dev)  \
  55         setup_sys_fs_device_files(dev, (acpi_device_sysfs_files *)&sysfs_create_file)
  56 #define remove_sysfs_device_files(dev)  \
  57         setup_sys_fs_device_files(dev, (acpi_device_sysfs_files *)&sysfs_remove_file)
  58
  59
  60 #define to_acpi_device(n) container_of(n, struct acpi_device, kobj)
  61 #define to_handle_attr(n) container_of(n, struct acpi_device_attribute, attr);
  62
  63 static ssize_t acpi_device_attr_show(struct kobject *kobj,
  64                 struct attribute *attr, char *buf)
  65 {
  66         struct acpi_device *device = to_acpi_device(kobj);
  67         struct acpi_device_attribute *attribute = to_handle_attr(attr);
  68         return attribute->show ? attribute->show(device, buf) : 0;
  69 }
  70 static ssize_t acpi_device_attr_store(struct kobject *kobj,
  71                 struct attribute *attr, const char *buf, size_t len)
  72 {
  73         struct acpi_device *device = to_acpi_device(kobj);
  74         struct acpi_device_attribute *attribute = to_handle_attr(attr);
  75         return attribute->store ? attribute->store(device, buf, len) : len;
  76 }
  77
  78 static struct sysfs_ops acpi_device_sysfs_ops = {
  79         .show   = acpi_device_attr_show,
  80         .store  = acpi_device_attr_store,
  81 };
  82
  83 static struct kobj_type ktype_acpi_ns = {
  84         .sysfs_ops      = &acpi_device_sysfs_ops,
  85         .release        = acpi_device_release,
  86 };
  87
  88 static int namespace_hotplug(struct kset *kset, struct kobject *kobj,
  89                              char **envp, int num_envp, char *buffer,
  90                              int buffer_size)
  91 {
  92         struct acpi_device *dev = to_acpi_device(kobj);
  93         int i = 0;
  94         int len = 0;
  95
  96         if (!dev->driver)
  97                 return 0;
  98
  99         if (add_hotplug_env_var(envp, num_envp, &i, buffer, buffer_size, &len,
 100                                 "PHYSDEVDRIVER=%s", dev->driver->name))
 101                 return -ENOMEM;
 102
 103         envp[i] = NULL;
 104
 105         return 0;
 106 }
 107
 108 static struct kset_hotplug_ops namespace_hotplug_ops = {
 109         .hotplug = &namespace_hotplug,
 110 };
 111
 112 static struct kset acpi_namespace_kset = {
 113         .kobj           = {
 114                 .name = "namespace",
 115         },
 116         .subsys = &acpi_subsys,
 117         .ktype  = &ktype_acpi_ns,
 118         .hotplug_ops = &namespace_hotplug_ops,
 119 };
 120
 121
 122 static void acpi_device_register(struct acpi_device * device, struct acpi_device * parent)
 123 {
 124         /*
 125          * Linkage
 126          * -------
 127          * Link this device to its parent and siblings.
 128          */
 129         INIT_LIST_HEAD(&device->children);
 130         INIT_LIST_HEAD(&device->node);
 131         INIT_LIST_HEAD(&device->g_list);
 132         INIT_LIST_HEAD(&device->wakeup_list);
 133
 134         spin_lock(&acpi_device_lock);
 135         if (device->parent) {
 136                 list_add_tail(&device->node, &device->parent->children);
 137                 list_add_tail(&device->g_list,&device->parent->g_list);
 138         } else
 139                 list_add_tail(&device->g_list,&acpi_device_list);
 140         if (device->wakeup.flags.valid)
 141                 list_add_tail(&device->wakeup_list,&acpi_wakeup_device_list);
 142         spin_unlock(&acpi_device_lock);
 143
 144         strlcpy(device->kobj.name,device->pnp.bus_id,KOBJ_NAME_LEN);
 145         if (parent)
 146                 device->kobj.parent = &parent->kobj;
 147         device->kobj.ktype = &ktype_acpi_ns;
 148         device->kobj.kset = &acpi_namespace_kset;
 149         kobject_register(&device->kobj);
 150         create_sysfs_device_files(device);
 151 }
 152
 153 static int
 154 acpi_device_unregister (
 155         struct acpi_device      *device,
 156         int                     type)
 157 {
 158         spin_lock(&acpi_device_lock);
 159         if (device->parent) {
 160                 list_del(&device->node);
 161                 list_del(&device->g_list);
 162         } else
 163                 list_del(&device->g_list);
 164
 165         list_del(&device->wakeup_list);
 166
 167         spin_unlock(&acpi_device_lock);
 168
 169         acpi_detach_data(device->handle, acpi_bus_data_handler);
 170         remove_sysfs_device_files(device);
 171         kobject_unregister(&device->kobj);
 172         return 0;
 173 }
 174
 175 void
 176 acpi_bus_data_handler (
 177         acpi_handle             handle,
 178         u32                     function,
 179         void                    *context)
 180 {
 181         ACPI_FUNCTION_TRACE("acpi_bus_data_handler");
 182
 183         /* TBD */
 184
 185         return_VOID;
 186 }
 187
 188 static int
 189 acpi_bus_get_power_flags (
 190         struct acpi_device      *device)
 191 {
 192         acpi_status             status = 0;
 193         acpi_handle             handle = NULL;
 194         u32                     i = 0;
 195
 196         ACPI_FUNCTION_TRACE("acpi_bus_get_power_flags");
 197
 198         /*
 199          * Power Management Flags
 200          */
 201         status = acpi_get_handle(device->handle, "_PSC", &handle);
 202         if (ACPI_SUCCESS(status))
 203                 device->power.flags.explicit_get = 1;
 204         status = acpi_get_handle(device->handle, "_IRC", &handle);
 205         if (ACPI_SUCCESS(status))
 206                 device->power.flags.inrush_current = 1;
 207
 208         /*
 209          * Enumerate supported power management states
 210          */
 211         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
 212                 struct acpi_device_power_state *ps = &device->power.states[i];
 213                 char            object_name[5] = {'_','P','R','0'+i,'\0'};
 214
 215                 /* Evaluate "_PRx" to se if power resources are referenced */
 216                 acpi_evaluate_reference(device->handle, object_name, NULL,
 217                         &ps->resources);
 218                 if (ps->resources.count) {
 219                         device->power.flags.power_resources = 1;
 220                         ps->flags.valid = 1;
 221                 }
 222
 223                 /* Evaluate "_PSx" to see if we can do explicit sets */
 224                 object_name[2] = 'S';
 225                 status = acpi_get_handle(device->handle, object_name, &handle);
 226                 if (ACPI_SUCCESS(status)) {
 227                         ps->flags.explicit_set = 1;
 228                         ps->flags.valid = 1;
 229                 }
 230
 231                 /* State is valid if we have some power control */
 232                 if (ps->resources.count || ps->flags.explicit_set)
 233                         ps->flags.valid = 1;
 234
 235                 ps->power = -1;         /* Unknown - driver assigned */
 236                 ps->latency = -1;       /* Unknown - driver assigned */
 237         }
 238
 239         /* Set defaults for D0 and D3 states (always valid) */
 240         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 241         device->power.states[ACPI_STATE_D0].power = 100;
 242         device->power.states[ACPI_STATE_D3].flags.valid = 1;
 243         device->power.states[ACPI_STATE_D3].power = 0;
 244
 245         /* TBD: System wake support and resource requirements. */
 246
 247         device->power.state = ACPI_STATE_UNKNOWN;
 248
 249         return_VALUE(0);
 250 }
 251
 252 int
 253 acpi_match_ids (
 254         struct acpi_device      *device,
 255         char                    *ids)
 256 {
 257         int error = 0;
 258         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 259
 260         if (device->flags.hardware_id)
 261                 if (strstr(ids, device->pnp.hardware_id))
 262                         goto Done;
 263
 264         if (device->flags.compatible_ids) {
 265                 struct acpi_compatible_id_list *cid_list = device->pnp.cid_list;
 266                 int i;
 267
 268                 /* compare multiple _CID entries against driver ids */
 269                 for (i = 0; i < cid_list->count; i++)
 270                 {
 271                         if (strstr(ids, cid_list->id[i].value))
 272                                 goto Done;
 273                 }
 274         }
 275         error = -ENOENT;
 276
 277  Done:
 278         if (buffer.pointer)
 279                 acpi_os_free(buffer.pointer);
 280         return error;
 281 }
 282
 283 static acpi_status
 284 acpi_bus_extract_wakeup_device_power_package (
 285         struct acpi_device      *device,
 286         union acpi_object       *package)
 287 {
 288         int      i = 0;
 289         union acpi_object       *element = NULL;
 290
 291         if (!device || !package || (package->package.count < 2))
 292                 return AE_BAD_PARAMETER;
 293
 294         element = &(package->package.elements[0]);
 295         if (!element)
 296                 return AE_BAD_PARAMETER;
 297         if (element->type == ACPI_TYPE_PACKAGE) {
 298                 if ((element->package.count < 2) ||
 299                         (element->package.elements[0].type != ACPI_TYPE_LOCAL_REFERENCE) ||
 300                         (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 301                         return AE_BAD_DATA;
 302                 device->wakeup.gpe_device = element->package.elements[0].reference.handle;
 303                 device->wakeup.gpe_number = (u32)element->package.elements[1].integer.value;
 304         }else if (element->type == ACPI_TYPE_INTEGER) {
 305                 device->wakeup.gpe_number = element->integer.value;
 306         }else
 307                 return AE_BAD_DATA;
 308
 309         element = &(package->package.elements[1]);
 310         if (element->type != ACPI_TYPE_INTEGER) {
 311                 return AE_BAD_DATA;
 312         }
 313         device->wakeup.sleep_state = element->integer.value;
 314
 315         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
 316                 return AE_NO_MEMORY;
 317         }
 318         device->wakeup.resources.count = package->package.count - 2;
 319         for (i=0; i < device->wakeup.resources.count; i++) {
 320                 element = &(package->package.elements[i + 2]);
 321                 if (element->type != ACPI_TYPE_ANY ) {
 322                         return AE_BAD_DATA;
 323                 }
 324
 325                 device->wakeup.resources.handles[i] = element->reference.handle;
 326         }
 327
 328         return AE_OK;
 329 }
 330
 331 static int
 332 acpi_bus_get_wakeup_device_flags (
 333         struct acpi_device      *device)
 334 {
 335         acpi_status     status = 0;
 336         struct acpi_buffer      buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 337         union acpi_object       *package = NULL;
 338
 339         ACPI_FUNCTION_TRACE("acpi_bus_get_wakeup_flags");
 340
 341         /* _PRW */
 342         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
 343         if (ACPI_FAILURE(status)) {
 344                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PRW\n"));
 345                 goto end;
 346         }
 347
 348         package = (union acpi_object *) buffer.pointer;
 349         status = acpi_bus_extract_wakeup_device_power_package(device, package);
 350         if (ACPI_FAILURE(status)) {
 351                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error extracting _PRW package\n"));
 352                 goto end;
 353         }
 354
 355         acpi_os_free(buffer.pointer);
 356
 357         device->wakeup.flags.valid = 1;
 358         /* Power button, Lid switch always enable wakeup*/
 359         if (!acpi_match_ids(device, "PNP0C0D,PNP0C0C,PNP0C0E"))
 360                 device->wakeup.flags.run_wake = 1;
 361
 362 end:
 363         if (ACPI_FAILURE(status))
 364                 device->flags.wake_capable = 0;
 365         return_VALUE(0);
 366 }
 367
 368 /* --------------------------------------------------------------------------
 369                 ACPI hotplug sysfs device file support
 370    -------------------------------------------------------------------------- */
 371 static ssize_t acpi_eject_store(struct acpi_device *device,
 372                 const char *buf, size_t count);
 373
 374 #define ACPI_DEVICE_ATTR(_name,_mode,_show,_store) \
 375 static struct acpi_device_attribute acpi_device_attr_##_name = \
 376                 __ATTR(_name, _mode, _show, _store)
 377
 378 ACPI_DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 379
 380 /**
 381  * setup_sys_fs_device_files - sets up the device files under device namespace
 382  * @@dev:       acpi_device object
 383  * @@func:      function pointer to create or destroy the device file
 384  */
 385 static void
 386 setup_sys_fs_device_files (
 387         struct acpi_device *dev,
 388         acpi_device_sysfs_files *func)
 389 {
 390         acpi_status             status;
 391         acpi_handle             temp = NULL;
 392
 393         /*
 394          * If device has _EJ0, 'eject' file is created that is used to trigger
 395          * hot-removal function from userland.
 396          */
 397         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 398         if (ACPI_SUCCESS(status))
 399                 (*(func))(&dev->kobj,&acpi_device_attr_eject.attr);
 400 }
 401
 402 static int
 403 acpi_eject_operation(acpi_handle handle, int lockable)
 404 {
 405         struct acpi_object_list arg_list;
 406         union acpi_object arg;
 407         acpi_status status = AE_OK;
 408
 409         /*
 410          * TBD: evaluate _PS3?
 411          */
 412
 413         if (lockable) {
 414                 arg_list.count = 1;
 415                 arg_list.pointer = &arg;
 416                 arg.type = ACPI_TYPE_INTEGER;
 417                 arg.integer.value = 0;
 418                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
 419         }
 420
 421         arg_list.count = 1;
 422         arg_list.pointer = &arg;
 423         arg.type = ACPI_TYPE_INTEGER;
 424         arg.integer.value = 1;
 425
 426         /*
 427          * TBD: _EJD support.
 428          */
 429
 430         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
 431         if (ACPI_FAILURE(status)) {
 432                 return(-ENODEV);
 433         }
 434
 435         return(0);
 436 }
 437
 438
 439 static ssize_t
 440 acpi_eject_store(struct acpi_device *device, const char *buf, size_t count)
 441 {
 442         int     result;
 443         int     ret = count;
 444         int     islockable;
 445         acpi_status     status;
 446         acpi_handle     handle;
 447         acpi_object_type        type = 0;
 448
 449         if ((!count) || (buf[0] != '1')) {
 450                 return -EINVAL;
 451         }
 452
 453 #ifndef FORCE_EJECT
 454         if (device->driver == NULL) {
 455                 ret = -ENODEV;
 456                 goto err;
 457         }
 458 #endif
 459         status = acpi_get_type(device->handle, &type);
 460         if (ACPI_FAILURE(status) || (!device->flags.ejectable) ) {
 461                 ret = -ENODEV;
 462                 goto err;
 463         }
 464
 465         islockable = device->flags.lockable;
 466         handle = device->handle;
 467
 468         if (type == ACPI_TYPE_PROCESSOR)
 469                 result = acpi_bus_trim(device, 0);
 470         else
 471                 result = acpi_bus_trim(device, 1);
 472
 473         if (!result)
 474                 result = acpi_eject_operation(handle, islockable);
 475
 476         if (result) {
 477                 ret = -EBUSY;
 478         }
 479 err:
 480         return ret;
 481 }
 482
 483
 484 /* --------------------------------------------------------------------------
 485                               Performance Management
 486    -------------------------------------------------------------------------- */
 487
 488 static int
 489 acpi_bus_get_perf_flags (
 490         struct acpi_device      *device)
 491 {
 492         device->performance.state = ACPI_STATE_UNKNOWN;
 493         return 0;
 494 }
 495
 496 /* --------------------------------------------------------------------------
 497                                  Driver Management
 498    -------------------------------------------------------------------------- */
 499
 500 static LIST_HEAD(acpi_bus_drivers);
 501 static DECLARE_MUTEX(acpi_bus_drivers_lock);
 502
 503
 504 /**
 505  * acpi_bus_match
 506  * --------------
 507  * Checks the device's hardware (_HID) or compatible (_CID) ids to see if it
 508  * matches the specified driver's criteria.
 509  */
 510 static int
 511 acpi_bus_match (
 512         struct acpi_device      *device,
 513         struct acpi_driver      *driver)
 514 {
 515         if (driver && driver->ops.match)
 516                 return driver->ops.match(device, driver);
 517         return acpi_match_ids(device, driver->ids);
 518 }
 519
 520
 521 /**
 522  * acpi_bus_driver_init
 523  * --------------------
 524  * Used to initialize a device via its device driver.  Called whenever a
 525  * driver is bound to a device.  Invokes the driver's add() and start() ops.
 526  */
 527 static int
 528 acpi_bus_driver_init (
 529         struct acpi_device      *device,
 530         struct acpi_driver      *driver)
 531 {
 532         int                     result = 0;
 533
 534         ACPI_FUNCTION_TRACE("acpi_bus_driver_init");
 535
 536         if (!device || !driver)
 537                 return_VALUE(-EINVAL);
 538
 539         if (!driver->ops.add)
 540                 return_VALUE(-ENOSYS);
 541
 542         result = driver->ops.add(device);
 543         if (result) {
 544                 device->driver = NULL;
 545                 acpi_driver_data(device) = NULL;
 546                 return_VALUE(result);
 547         }
 548
 549         device->driver = driver;
 550
 551         /*
 552          * TBD - Configuration Management: Assign resources to device based
 553          * upon possible configuration and currently allocated resources.
 554          */
 555
 556         if (driver->ops.start) {
 557                 result = driver->ops.start(device);
 558                 if (result && driver->ops.remove)
 559                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
 560                 return_VALUE(result);
 561         }
 562
 563         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Driver successfully bound to device\n"));
 564
 565         if (driver->ops.scan) {
 566                 driver->ops.scan(device);
 567         }
 568
 569         return_VALUE(0);
 570 }
 571
 572 static int acpi_driver_attach(struct acpi_driver * drv)
 573 {
 574         struct list_head * node, * next;
 575         int count = 0;
 576
 577         ACPI_FUNCTION_TRACE("acpi_driver_attach");
 578
 579         spin_lock(&acpi_device_lock);
 580         list_for_each_safe(node, next, &acpi_device_list) {
 581                 struct acpi_device * dev = container_of(node, struct acpi_device, g_list);
 582
 583                 if (dev->driver || !dev->status.present)
 584                         continue;
 585                 spin_unlock(&acpi_device_lock);
 586
 587                 if (!acpi_bus_match(dev, drv)) {
 588                         if (!acpi_bus_driver_init(dev, drv)) {
 589                                 atomic_inc(&drv->references);
 590                                 count++;
 591                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
 592                                                   drv->name, dev->pnp.bus_id));
 593                         }
 594                 }
 595                 spin_lock(&acpi_device_lock);
 596         }
 597         spin_unlock(&acpi_device_lock);
 598         return_VALUE(count);
 599 }
 600
 601 static int acpi_driver_detach(struct acpi_driver * drv)
 602 {
 603         struct list_head * node, * next;
 604
 605         ACPI_FUNCTION_TRACE("acpi_driver_detach");
 606
 607         spin_lock(&acpi_device_lock);
 608         list_for_each_safe(node,next,&acpi_device_list) {
 609                 struct acpi_device * dev = container_of(node,struct acpi_device,g_list);
 610
 611                 if (dev->driver == drv) {
 612                         spin_unlock(&acpi_device_lock);
 613                         if (drv->ops.remove)
 614                                 drv->ops.remove(dev,ACPI_BUS_REMOVAL_NORMAL);
 615                         spin_lock(&acpi_device_lock);
 616                         dev->driver = NULL;
 617                         dev->driver_data = NULL;
 618                         atomic_dec(&drv->references);
 619                 }
 620         }
 621         spin_unlock(&acpi_device_lock);
 622         return_VALUE(0);
 623 }
 624
 625 /**
 626  * acpi_bus_register_driver
 627  * ------------------------
 628  * Registers a driver with the ACPI bus.  Searches the namespace for all
 629  * devices that match the driver's criteria and binds.  Returns the
 630  * number of devices that were claimed by the driver, or a negative
 631  * error status for failure.
 632  */
 633 int
 634 acpi_bus_register_driver (
 635         struct acpi_driver      *driver)
 636 {
 637         int count;
 638
 639         ACPI_FUNCTION_TRACE("acpi_bus_register_driver");
 640
 641         if (acpi_disabled)
 642                 return_VALUE(-ENODEV);
 643
 644         if (!driver)
 645                 return_VALUE(-EINVAL);
 646
 647         spin_lock(&acpi_device_lock);
 648         list_add_tail(&driver->node, &acpi_bus_drivers);
 649         spin_unlock(&acpi_device_lock);
 650         count = acpi_driver_attach(driver);
 651
 652         return_VALUE(count);
 653 }
 654 EXPORT_SYMBOL(acpi_bus_register_driver);
 655
 656
 657 /**
 658  * acpi_bus_unregister_driver
 659  * --------------------------
 660  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
 661  * devices that match the driver's criteria and unbinds.
 662  */
 663 int
 664 acpi_bus_unregister_driver (
 665         struct acpi_driver      *driver)
 666 {
 667         int error = 0;
 668
 669         ACPI_FUNCTION_TRACE("acpi_bus_unregister_driver");
 670
 671         if (driver) {
 672                 acpi_driver_detach(driver);
 673
 674                 if (!atomic_read(&driver->references)) {
 675                         spin_lock(&acpi_device_lock);
 676                         list_del_init(&driver->node);
 677                         spin_unlock(&acpi_device_lock);
 678                 }
 679         } else
 680                 error = -EINVAL;
 681         return_VALUE(error);
 682 }
 683 EXPORT_SYMBOL(acpi_bus_unregister_driver);
 684
 685 /**
 686  * acpi_bus_find_driver
 687  * --------------------
 688  * Parses the list of registered drivers looking for a driver applicable for
 689  * the specified device.
 690  */
 691 static int
 692 acpi_bus_find_driver (
 693         struct acpi_device      *device)
 694 {
 695         int                     result = 0;
 696         struct list_head        * node, *next;
 697
 698         ACPI_FUNCTION_TRACE("acpi_bus_find_driver");
 699
 700         spin_lock(&acpi_device_lock);
 701         list_for_each_safe(node,next,&acpi_bus_drivers) {
 702                 struct acpi_driver * driver = container_of(node,struct acpi_driver,node);
 703
 704                 atomic_inc(&driver->references);
 705                 spin_unlock(&acpi_device_lock);
 706                 if (!acpi_bus_match(device, driver)) {
 707                         result = acpi_bus_driver_init(device, driver);
 708                         if (!result)
 709                                 goto Done;
 710                 }
 711                 atomic_dec(&driver->references);
 712                 spin_lock(&acpi_device_lock);
 713         }
 714         spin_unlock(&acpi_device_lock);
 715
 716  Done:
 717         return_VALUE(result);
 718 }
 719
 720
 721 /* --------------------------------------------------------------------------
 722                                  Device Enumeration
 723    -------------------------------------------------------------------------- */
 724
 725 static int
 726 acpi_bus_get_flags (
 727         struct acpi_device      *device)
 728 {
 729         acpi_status             status = AE_OK;
 730         acpi_handle             temp = NULL;
 731
 732         ACPI_FUNCTION_TRACE("acpi_bus_get_flags");
 733
 734         /* Presence of _STA indicates 'dynamic_status' */
 735         status = acpi_get_handle(device->handle, "_STA", &temp);
 736         if (ACPI_SUCCESS(status))
 737                 device->flags.dynamic_status = 1;
 738
 739         /* Presence of _CID indicates 'compatible_ids' */
 740         status = acpi_get_handle(device->handle, "_CID", &temp);
 741         if (ACPI_SUCCESS(status))
 742                 device->flags.compatible_ids = 1;
 743
 744         /* Presence of _RMV indicates 'removable' */
 745         status = acpi_get_handle(device->handle, "_RMV", &temp);
 746         if (ACPI_SUCCESS(status))
 747                 device->flags.removable = 1;
 748
 749         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 750         status = acpi_get_handle(device->handle, "_EJD", &temp);
 751         if (ACPI_SUCCESS(status))
 752                 device->flags.ejectable = 1;
 753         else {
 754                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
 755                 if (ACPI_SUCCESS(status))
 756                         device->flags.ejectable = 1;
 757         }
 758
 759         /* Presence of _LCK indicates 'lockable' */
 760         status = acpi_get_handle(device->handle, "_LCK", &temp);
 761         if (ACPI_SUCCESS(status))
 762                 device->flags.lockable = 1;
 763
 764         /* Presence of _PS0|_PR0 indicates 'power manageable' */
 765         status = acpi_get_handle(device->handle, "_PS0", &temp);
 766         if (ACPI_FAILURE(status))
 767                 status = acpi_get_handle(device->handle, "_PR0", &temp);
 768         if (ACPI_SUCCESS(status))
 769                 device->flags.power_manageable = 1;
 770
 771         /* Presence of _PRW indicates wake capable */
 772         status = acpi_get_handle(device->handle, "_PRW", &temp);
 773         if (ACPI_SUCCESS(status))
 774                 device->flags.wake_capable = 1;
 775
 776         /* TBD: Peformance management */
 777
 778         return_VALUE(0);
 779 }
 780
 781 static void acpi_device_get_busid(struct acpi_device * device, acpi_handle handle, int type)
 782 {
 783         char                    bus_id[5] = {'?',0};
 784         struct acpi_buffer      buffer = {sizeof(bus_id), bus_id};
 785         int                     i = 0;
 786
 787         /*
 788          * Bus ID
 789          * ------
 790          * The device's Bus ID is simply the object name.
 791          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
 792          */
 793         switch (type) {
 794         case ACPI_BUS_TYPE_SYSTEM:
 795                 strcpy(device->pnp.bus_id, "ACPI");
 796                 break;
 797         case ACPI_BUS_TYPE_POWER_BUTTON:
 798                 strcpy(device->pnp.bus_id, "PWRF");
 799                 break;
 800         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 801                 strcpy(device->pnp.bus_id, "SLPF");
 802                 break;
 803         default:
 804                 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 805                 /* Clean up trailing underscores (if any) */
 806                 for (i = 3; i > 1; i--) {
 807                         if (bus_id[i] == '_')
 808                                 bus_id[i] = '\0';
 809                         else
 810                                 break;
 811                 }
 812                 strcpy(device->pnp.bus_id, bus_id);
 813                 break;
 814         }
 815 }
 816
 817 static void acpi_device_set_id(struct acpi_device * device, struct acpi_device * parent,
 818                                acpi_handle handle, int type)
 819 {
 820         struct acpi_device_info *info;
 821         struct acpi_buffer      buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 822         char                    *hid = NULL;
 823         char                    *uid = NULL;
 824         struct acpi_compatible_id_list *cid_list = NULL;
 825         acpi_status             status;
 826
 827         switch (type) {
 828         case ACPI_BUS_TYPE_DEVICE:
 829                 status = acpi_get_object_info(handle, &buffer);
 830                 if (ACPI_FAILURE(status)) {
 831                         printk("%s: Error reading device info\n",__FUNCTION__);
 832                         return;
 833                 }
 834
 835                 info = buffer.pointer;
 836                 if (info->valid & ACPI_VALID_HID)
 837                         hid = info->hardware_id.value;
 838                 if (info->valid & ACPI_VALID_UID)
 839                         uid = info->unique_id.value;
 840                 if (info->valid & ACPI_VALID_CID)
 841                         cid_list = &info->compatibility_id;
 842                 if (info->valid & ACPI_VALID_ADR) {
 843                         device->pnp.bus_address = info->address;
 844                         device->flags.bus_address = 1;
 845                 }
 846                 break;
 847         case ACPI_BUS_TYPE_POWER:
 848                 hid = ACPI_POWER_HID;
 849                 break;
 850         case ACPI_BUS_TYPE_PROCESSOR:
 851                 hid = ACPI_PROCESSOR_HID;
 852                 break;
 853         case ACPI_BUS_TYPE_SYSTEM:
 854                 hid = ACPI_SYSTEM_HID;
 855                 break;
 856         case ACPI_BUS_TYPE_THERMAL:
 857                 hid = ACPI_THERMAL_HID;
 858                 break;
 859         case ACPI_BUS_TYPE_POWER_BUTTON:
 860                 hid = ACPI_BUTTON_HID_POWERF;
 861                 break;
 862         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 863                 hid = ACPI_BUTTON_HID_SLEEPF;
 864                 break;
 865         }
 866
 867         /*
 868          * \_SB
 869          * ----
 870          * Fix for the system root bus device -- the only root-level device.
 871          */
 872         if ((parent == ACPI_ROOT_OBJECT) && (type == ACPI_BUS_TYPE_DEVICE)) {
 873                 hid = ACPI_BUS_HID;
 874                 strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
 875                 strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
 876         }
 877
 878         if (hid) {
 879                 strcpy(device->pnp.hardware_id, hid);
 880                 device->flags.hardware_id = 1;
 881         }
 882         if (uid) {
 883                 strcpy(device->pnp.unique_id, uid);
 884                 device->flags.unique_id = 1;
 885         }
 886         if (cid_list) {
 887                 device->pnp.cid_list = kmalloc(cid_list->size, GFP_KERNEL);
 888                 if (device->pnp.cid_list)
 889                         memcpy(device->pnp.cid_list, cid_list, cid_list->size);
 890                 else
 891                         printk(KERN_ERR "Memory allocation error\n");
 892         }
 893
 894         acpi_os_free(buffer.pointer);
 895 }
 896
 897 static int acpi_device_set_context(struct acpi_device * device, int type)
 898 {
 899         acpi_status status = AE_OK;
 900         int result = 0;
 901         /*
 902          * Context
 903          * -------
 904          * Attach this 'struct acpi_device' to the ACPI object.  This makes
 905          * resolutions from handle->device very efficient.  Note that we need
 906          * to be careful with fixed-feature devices as they all attach to the
 907          * root object.
 908          */
 909         if (type != ACPI_BUS_TYPE_POWER_BUTTON &&
 910             type != ACPI_BUS_TYPE_SLEEP_BUTTON) {
 911                 status = acpi_attach_data(device->handle,
 912                         acpi_bus_data_handler, device);
 913
 914                 if (ACPI_FAILURE(status)) {
 915                         printk("Error attaching device data\n");
 916                         result = -ENODEV;
 917                 }
 918         }
 919         return result;
 920 }
 921
 922 static void acpi_device_get_debug_info(struct acpi_device * device, acpi_handle handle, int type)
 923 {
 924 #ifdef CONFIG_ACPI_DEBUG_OUTPUT
 925         char            *type_string = NULL;
 926         char            name[80] = {'?','\0'};
 927         struct acpi_buffer      buffer = {sizeof(name), name};
 928
 929         switch (type) {
 930         case ACPI_BUS_TYPE_DEVICE:
 931                 type_string = "Device";
 932                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 933                 break;
 934         case ACPI_BUS_TYPE_POWER:
 935                 type_string = "Power Resource";
 936                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 937                 break;
 938         case ACPI_BUS_TYPE_PROCESSOR:
 939                 type_string = "Processor";
 940                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 941                 break;
 942         case ACPI_BUS_TYPE_SYSTEM:
 943                 type_string = "System";
 944                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 945                 break;
 946         case ACPI_BUS_TYPE_THERMAL:
 947                 type_string = "Thermal Zone";
 948                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 949                 break;
 950         case ACPI_BUS_TYPE_POWER_BUTTON:
 951                 type_string = "Power Button";
 952                 sprintf(name, "PWRB");
 953                 break;
 954         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 955                 type_string = "Sleep Button";
 956                 sprintf(name, "SLPB");
 957                 break;
 958         }
 959
 960         printk(KERN_DEBUG "Found %s %s [%p]\n", type_string, name, handle);
 961 #endif /*CONFIG_ACPI_DEBUG_OUTPUT*/
 962 }
 963
 964
 965 static int
 966 acpi_bus_remove (
 967         struct acpi_device *dev,
 968         int rmdevice)
 969 {
 970         int                     result = 0;
 971         struct acpi_driver      *driver;
 972
 973         ACPI_FUNCTION_TRACE("acpi_bus_remove");
 974
 975         if (!dev)
 976                 return_VALUE(-EINVAL);
 977
 978         driver = dev->driver;
 979
 980         if ((driver) && (driver->ops.remove)) {
 981
 982                 if (driver->ops.stop) {
 983                         result = driver->ops.stop(dev, ACPI_BUS_REMOVAL_EJECT);
 984                         if (result)
 985                                 return_VALUE(result);
 986                 }
 987
 988                 result = dev->driver->ops.remove(dev, ACPI_BUS_REMOVAL_EJECT);
 989                 if (result) {
 990                         return_VALUE(result);
 991                 }
 992
 993                 atomic_dec(&dev->driver->references);
 994                 dev->driver = NULL;
 995                 acpi_driver_data(dev) = NULL;
 996         }
 997
 998         if (!rmdevice)
 999                 return_VALUE(0);
1000
1001         if (dev->flags.bus_address) {
1002                 if ((dev->parent) && (dev->parent->ops.unbind))
1003                         dev->parent->ops.unbind(dev);
1004         }
1005
1006         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1007
1008         return_VALUE(0);
1009 }
1010
1011
1012 int
1013 acpi_bus_add (
1014         struct acpi_device      **child,
1015         struct acpi_device      *parent,
1016         acpi_handle             handle,
1017         int                     type)
1018 {
1019         int                     result = 0;
1020         struct acpi_device      *device = NULL;
1021
1022         ACPI_FUNCTION_TRACE("acpi_bus_add");
1023
1024         if (!child)
1025                 return_VALUE(-EINVAL);
1026
1027         device = kmalloc(sizeof(struct acpi_device), GFP_KERNEL);
1028         if (!device) {
1029                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Memory allocation error\n"));
1030                 return_VALUE(-ENOMEM);
1031         }
1032         memset(device, 0, sizeof(struct acpi_device));
1033
1034         device->handle = handle;
1035         device->parent = parent;
1036
1037         acpi_device_get_busid(device,handle,type);
1038
1039         /*
1040          * Flags
1041          * -----
1042          * Get prior to calling acpi_bus_get_status() so we know whether
1043          * or not _STA is present.  Note that we only look for object
1044          * handles -- cannot evaluate objects until we know the device is
1045          * present and properly initialized.
1046          */
1047         result = acpi_bus_get_flags(device);
1048         if (result)
1049                 goto end;
1050
1051         /*
1052          * Status
1053          * ------
1054          * See if the device is present.  We always assume that non-Device()
1055          * objects (e.g. thermal zones, power resources, processors, etc.) are
1056          * present, functioning, etc. (at least when parent object is present).
1057          * Note that _STA has a different meaning for some objects (e.g.
1058          * power resources) so we need to be careful how we use it.
1059          */
1060         switch (type) {
1061         case ACPI_BUS_TYPE_DEVICE:
1062                 result = acpi_bus_get_status(device);
1063                 if (ACPI_FAILURE(result) || !device->status.present) {
1064                         result = -ENOENT;
1065                         goto end;
1066                 }
1067                 break;
1068         default:
1069                 STRUCT_TO_INT(device->status) = 0x0F;
1070                 break;
1071         }
1072
1073         /*
1074          * Initialize Device
1075          * -----------------
1076          * TBD: Synch with Core's enumeration/initialization process.
1077          */
1078
1079         /*
1080          * Hardware ID, Unique ID, & Bus Address
1081          * -------------------------------------
1082          */
1083         acpi_device_set_id(device,parent,handle,type);
1084
1085         /*
1086          * Power Management
1087          * ----------------
1088          */
1089         if (device->flags.power_manageable) {
1090                 result = acpi_bus_get_power_flags(device);
1091                 if (result)
1092                         goto end;
1093         }
1094
1095         /*
1096          * Wakeup device management
1097          *-----------------------
1098          */
1099         if (device->flags.wake_capable) {
1100                 result = acpi_bus_get_wakeup_device_flags(device);
1101                 if (result)
1102                         goto end;
1103         }
1104
1105         /*
1106          * Performance Management
1107          * ----------------------
1108          */
1109         if (device->flags.performance_manageable) {
1110                 result = acpi_bus_get_perf_flags(device);
1111                 if (result)
1112                         goto end;
1113         }
1114
1115         if ((result = acpi_device_set_context(device,type)))
1116                 goto end;
1117
1118         acpi_device_get_debug_info(device,handle,type);
1119
1120         acpi_device_register(device,parent);
1121
1122         /*
1123          * Bind _ADR-Based Devices
1124          * -----------------------
1125          * If there's a a bus address (_ADR) then we utilize the parent's
1126          * 'bind' function (if exists) to bind the ACPI- and natively-
1127          * enumerated device representations.
1128          */
1129         if (device->flags.bus_address) {
1130                 if (device->parent && device->parent->ops.bind)
1131                         device->parent->ops.bind(device);
1132         }
1133
1134         /*
1135          * Locate & Attach Driver
1136          * ----------------------
1137          * If there's a hardware id (_HID) or compatible ids (_CID) we check
1138          * to see if there's a driver installed for this kind of device.  Note
1139          * that drivers can install before or after a device is enumerated.
1140          *
1141          * TBD: Assumes LDM provides driver hot-plug capability.
1142          */
1143         acpi_bus_find_driver(device);
1144
1145 end:
1146         if (!result)
1147                 *child = device;
1148         else {
1149                 if (device->pnp.cid_list)
1150                         kfree(device->pnp.cid_list);
1151                 kfree(device);
1152         }
1153
1154         return_VALUE(result);
1155 }
1156 EXPORT_SYMBOL(acpi_bus_add);
1157
1158
1159 int acpi_bus_scan (struct acpi_device   *start)
1160 {
1161         acpi_status             status = AE_OK;
1162         struct acpi_device      *parent = NULL;
1163         struct acpi_device      *child = NULL;
1164         acpi_handle             phandle = NULL;
1165         acpi_handle             chandle = NULL;
1166         acpi_object_type        type = 0;
1167         u32                     level = 1;
1168
1169         ACPI_FUNCTION_TRACE("acpi_bus_scan");
1170
1171         if (!start)
1172                 return_VALUE(-EINVAL);
1173
1174         parent = start;
1175         phandle = start->handle;
1176
1177         /*
1178          * Parse through the ACPI namespace, identify all 'devices', and
1179          * create a new 'struct acpi_device' for each.
1180          */
1181         while ((level > 0) && parent) {
1182
1183                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1184                         chandle, &chandle);
1185
1186                 /*
1187                  * If this scope is exhausted then move our way back up.
1188                  */
1189                 if (ACPI_FAILURE(status)) {
1190                         level--;
1191                         chandle = phandle;
1192                         acpi_get_parent(phandle, &phandle);
1193                         if (parent->parent)
1194                                 parent = parent->parent;
1195                         continue;
1196                 }
1197
1198                 status = acpi_get_type(chandle, &type);
1199                 if (ACPI_FAILURE(status))
1200                         continue;
1201
1202                 /*
1203                  * If this is a scope object then parse it (depth-first).
1204                  */
1205                 if (type == ACPI_TYPE_LOCAL_SCOPE) {
1206                         level++;
1207                         phandle = chandle;
1208                         chandle = NULL;
1209                         continue;
1210                 }
1211
1212                 /*
1213                  * We're only interested in objects that we consider 'devices'.
1214                  */
1215                 switch (type) {
1216                 case ACPI_TYPE_DEVICE:
1217                         type = ACPI_BUS_TYPE_DEVICE;
1218                         break;
1219                 case ACPI_TYPE_PROCESSOR:
1220                         type = ACPI_BUS_TYPE_PROCESSOR;
1221                         break;
1222                 case ACPI_TYPE_THERMAL:
1223                         type = ACPI_BUS_TYPE_THERMAL;
1224                         break;
1225                 case ACPI_TYPE_POWER:
1226                         type = ACPI_BUS_TYPE_POWER;
1227                         break;
1228                 default:
1229                         continue;
1230                 }
1231
1232                 status = acpi_bus_add(&child, parent, chandle, type);
1233                 if (ACPI_FAILURE(status))
1234                         continue;
1235
1236                 /*
1237                  * If the device is present, enabled, and functioning then
1238                  * parse its scope (depth-first).  Note that we need to
1239                  * represent absent devices to facilitate PnP notifications
1240                  * -- but only the subtree head (not all of its children,
1241                  * which will be enumerated when the parent is inserted).
1242                  *
1243                  * TBD: Need notifications and other detection mechanisms
1244                  *      in place before we can fully implement this.
1245                  */
1246                 if (child->status.present) {
1247                         status = acpi_get_next_object(ACPI_TYPE_ANY, chandle,
1248                                                       NULL, NULL);
1249                         if (ACPI_SUCCESS(status)) {
1250                                 level++;
1251                                 phandle = chandle;
1252                                 chandle = NULL;
1253                                 parent = child;
1254                         }
1255                 }
1256         }
1257
1258         return_VALUE(0);
1259 }
1260 EXPORT_SYMBOL(acpi_bus_scan);
1261
1262
1263 static int
1264 acpi_bus_trim(struct acpi_device        *start,
1265                 int rmdevice)
1266 {
1267         acpi_status             status;
1268         struct acpi_device      *parent, *child;
1269         acpi_handle             phandle, chandle;
1270         acpi_object_type        type;
1271         u32                     level = 1;
1272         int                     err = 0;
1273
1274         parent  = start;
1275         phandle = start->handle;
1276         child = chandle = NULL;
1277
1278         while ((level > 0) && parent && (!err)) {
1279                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1280                         chandle, &chandle);
1281
1282                 /*
1283                  * If this scope is exhausted then move our way back up.
1284                  */
1285                 if (ACPI_FAILURE(status)) {
1286                         level--;
1287                         chandle = phandle;
1288                         acpi_get_parent(phandle, &phandle);
1289                         child = parent;
1290                         parent = parent->parent;
1291
1292                         if (level == 0)
1293                                 err = acpi_bus_remove(child, rmdevice);
1294                         else
1295                                 err = acpi_bus_remove(child, 1);
1296
1297                         continue;
1298                 }
1299
1300                 status = acpi_get_type(chandle, &type);
1301                 if (ACPI_FAILURE(status)) {
1302                         continue;
1303                 }
1304                 /*
1305                  * If there is a device corresponding to chandle then
1306                  * parse it (depth-first).
1307                  */
1308                 if (acpi_bus_get_device(chandle, &child) == 0) {
1309                         level++;
1310                         phandle = chandle;
1311                         chandle = NULL;
1312                         parent = child;
1313                 }
1314                 continue;
1315         }
1316         return err;
1317 }
1318
1319 static int
1320 acpi_bus_scan_fixed (
1321         struct acpi_device      *root)
1322 {
1323         int                     result = 0;
1324         struct acpi_device      *device = NULL;
1325
1326         ACPI_FUNCTION_TRACE("acpi_bus_scan_fixed");
1327
1328         if (!root)
1329                 return_VALUE(-ENODEV);
1330
1331         /*
1332          * Enumerate all fixed-feature devices.
1333          */
1334         if (acpi_fadt.pwr_button == 0)
1335                 result = acpi_bus_add(&device, acpi_root,
1336                         NULL, ACPI_BUS_TYPE_POWER_BUTTON);
1337
1338         if (acpi_fadt.sleep_button == 0)
1339                 result = acpi_bus_add(&device, acpi_root,
1340                         NULL, ACPI_BUS_TYPE_SLEEP_BUTTON);
1341
1342         return_VALUE(result);
1343 }
1344
1345
1346 static int __init acpi_scan_init(void)
1347 {
1348         int result;
1349
1350         ACPI_FUNCTION_TRACE("acpi_scan_init");
1351
1352         if (acpi_disabled)
1353                 return_VALUE(0);
1354
1355         kset_register(&acpi_namespace_kset);
1356
1357         /*
1358          * Create the root device in the bus's device tree
1359          */
1360         result = acpi_bus_add(&acpi_root, NULL, ACPI_ROOT_OBJECT,
1361                 ACPI_BUS_TYPE_SYSTEM);
1362         if (result)
1363                 goto Done;
1364
1365         /*
1366          * Enumerate devices in the ACPI namespace.
1367          */
1368         result = acpi_bus_scan_fixed(acpi_root);
1369         if (!result)
1370                 result = acpi_bus_scan(acpi_root);
1371
1372         if (result)
1373                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1374
1375  Done:
1376         return_VALUE(result);
1377 }
1378
1379 subsys_initcall(acpi_scan_init);