git.oblomov.eu Git - linux-2.6/blob - drivers/acpi/wmi.c

   1 /*
   2  *  ACPI-WMI mapping driver
   3  *
   4  *  Copyright (C) 2007-2008 Carlos Corbacho <carlos@strangeworlds.co.uk>
   5  *
   6  *  GUID parsing code from ldm.c is:
   7  *   Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
   8  *   Copyright (c) 2001-2007 Anton Altaparmakov
   9  *   Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
  10  *
  11  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  12  *
  13  *  This program is free software; you can redistribute it and/or modify
  14  *  it under the terms of the GNU General Public License as published by
  15  *  the Free Software Foundation; either version 2 of the License, or (at
  16  *  your option) any later version.
  17  *
  18  *  This program is distributed in the hope that it will be useful, but
  19  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  20  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21  *  General Public License for more details.
  22  *
  23  *  You should have received a copy of the GNU General Public License along
  24  *  with this program; if not, write to the Free Software Foundation, Inc.,
  25  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  26  *
  27  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  28  */
  29
  30 #include <linux/kernel.h>
  31 #include <linux/init.h>
  32 #include <linux/types.h>
  33 #include <linux/list.h>
  34 #include <linux/acpi.h>
  35 #include <acpi/acpi_bus.h>
  36 #include <acpi/acpi_drivers.h>
  37
  38 ACPI_MODULE_NAME("wmi");
  39 MODULE_AUTHOR("Carlos Corbacho");
  40 MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
  41 MODULE_LICENSE("GPL");
  42
  43 #define ACPI_WMI_CLASS "wmi"
  44
  45 #undef PREFIX
  46 #define PREFIX "ACPI: WMI: "
  47
  48 static DEFINE_MUTEX(wmi_data_lock);
  49
  50 struct guid_block {
  51         char guid[16];
  52         union {
  53                 char object_id[2];
  54                 struct {
  55                         unsigned char notify_id;
  56                         unsigned char reserved;
  57                 };
  58         };
  59         u8 instance_count;
  60         u8 flags;
  61 };
  62
  63 struct wmi_block {
  64         struct list_head list;
  65         struct guid_block gblock;
  66         acpi_handle handle;
  67         wmi_notify_handler handler;
  68         void *handler_data;
  69 };
  70
  71 static struct wmi_block wmi_blocks;
  72
  73 /*
  74  * If the GUID data block is marked as expensive, we must enable and
  75  * explicitily disable data collection.
  76  */
  77 #define ACPI_WMI_EXPENSIVE   0x1
  78 #define ACPI_WMI_METHOD      0x2        /* GUID is a method */
  79 #define ACPI_WMI_STRING      0x4        /* GUID takes & returns a string */
  80 #define ACPI_WMI_EVENT       0x8        /* GUID is an event */
  81
  82 static int acpi_wmi_remove(struct acpi_device *device, int type);
  83 static int acpi_wmi_add(struct acpi_device *device);
  84
  85 static const struct acpi_device_id wmi_device_ids[] = {
  86         {"PNP0C14", 0},
  87         {"pnp0c14", 0},
  88         {"", 0},
  89 };
  90 MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
  91
  92 static struct acpi_driver acpi_wmi_driver = {
  93         .name = "wmi",
  94         .class = ACPI_WMI_CLASS,
  95         .ids = wmi_device_ids,
  96         .ops = {
  97                 .add = acpi_wmi_add,
  98                 .remove = acpi_wmi_remove,
  99                 },
 100 };
 101
 102 /*
 103  * GUID parsing functions
 104  */
 105
 106 /**
 107  * wmi_parse_hexbyte - Convert a ASCII hex number to a byte
 108  * @src:  Pointer to at least 2 characters to convert.
 109  *
 110  * Convert a two character ASCII hex string to a number.
 111  *
 112  * Return:  0-255  Success, the byte was parsed correctly
 113  *          -1     Error, an invalid character was supplied
 114  */
 115 static int wmi_parse_hexbyte(const u8 *src)
 116 {
 117         unsigned int x; /* For correct wrapping */
 118         int h;
 119
 120         /* high part */
 121         x = src[0];
 122         if (x - '0' <= '9' - '0') {
 123                 h = x - '0';
 124         } else if (x - 'a' <= 'f' - 'a') {
 125                 h = x - 'a' + 10;
 126         } else if (x - 'A' <= 'F' - 'A') {
 127                 h = x - 'A' + 10;
 128         } else {
 129                 return -1;
 130         }
 131         h <<= 4;
 132
 133         /* low part */
 134         x = src[1];
 135         if (x - '0' <= '9' - '0')
 136                 return h | (x - '0');
 137         if (x - 'a' <= 'f' - 'a')
 138                 return h | (x - 'a' + 10);
 139         if (x - 'A' <= 'F' - 'A')
 140                 return h | (x - 'A' + 10);
 141         return -1;
 142 }
 143
 144 /**
 145  * wmi_swap_bytes - Rearrange GUID bytes to match GUID binary
 146  * @src:   Memory block holding binary GUID (16 bytes)
 147  * @dest:  Memory block to hold byte swapped binary GUID (16 bytes)
 148  *
 149  * Byte swap a binary GUID to match it's real GUID value
 150  */
 151 static void wmi_swap_bytes(u8 *src, u8 *dest)
 152 {
 153         int i;
 154
 155         for (i = 0; i <= 3; i++)
 156                 memcpy(dest + i, src + (3 - i), 1);
 157
 158         for (i = 0; i <= 1; i++)
 159                 memcpy(dest + 4 + i, src + (5 - i), 1);
 160
 161         for (i = 0; i <= 1; i++)
 162                 memcpy(dest + 6 + i, src + (7 - i), 1);
 163
 164         memcpy(dest + 8, src + 8, 8);
 165 }
 166
 167 /**
 168  * wmi_parse_guid - Convert GUID from ASCII to binary
 169  * @src:   36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 170  * @dest:  Memory block to hold binary GUID (16 bytes)
 171  *
 172  * N.B. The GUID need not be NULL terminated.
 173  *
 174  * Return:  'true'   @dest contains binary GUID
 175  *          'false'  @dest contents are undefined
 176  */
 177 static bool wmi_parse_guid(const u8 *src, u8 *dest)
 178 {
 179         static const int size[] = { 4, 2, 2, 2, 6 };
 180         int i, j, v;
 181
 182         if (src[8]  != '-' || src[13] != '-' ||
 183                 src[18] != '-' || src[23] != '-')
 184                 return false;
 185
 186         for (j = 0; j < 5; j++, src++) {
 187                 for (i = 0; i < size[j]; i++, src += 2, *dest++ = v) {
 188                         v = wmi_parse_hexbyte(src);
 189                         if (v < 0)
 190                                 return false;
 191                 }
 192         }
 193
 194         return true;
 195 }
 196
 197 static bool find_guid(const char *guid_string, struct wmi_block **out)
 198 {
 199         char tmp[16], guid_input[16];
 200         struct wmi_block *wblock;
 201         struct guid_block *block;
 202         struct list_head *p;
 203
 204         wmi_parse_guid(guid_string, tmp);
 205         wmi_swap_bytes(tmp, guid_input);
 206
 207         list_for_each(p, &wmi_blocks.list) {
 208                 wblock = list_entry(p, struct wmi_block, list);
 209                 block = &wblock->gblock;
 210
 211                 if (memcmp(block->guid, guid_input, 16) == 0) {
 212                         if (out)
 213                                 *out = wblock;
 214                         return 1;
 215                 }
 216         }
 217         return 0;
 218 }
 219
 220 static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
 221 {
 222         struct guid_block *block = NULL;
 223         char method[5];
 224         struct acpi_object_list input;
 225         union acpi_object params[1];
 226         acpi_status status;
 227         acpi_handle handle;
 228
 229         block = &wblock->gblock;
 230         handle = wblock->handle;
 231
 232         if (!block)
 233                 return AE_NOT_EXIST;
 234
 235         input.count = 1;
 236         input.pointer = params;
 237         params[0].type = ACPI_TYPE_INTEGER;
 238         params[0].integer.value = enable;
 239
 240         snprintf(method, 5, "WE%02X", block->notify_id);
 241         status = acpi_evaluate_object(handle, method, &input, NULL);
 242
 243         if (status != AE_OK && status != AE_NOT_FOUND)
 244                 return status;
 245         else
 246                 return AE_OK;
 247 }
 248
 249 /*
 250  * Exported WMI functions
 251  */
 252 /**
 253  * wmi_evaluate_method - Evaluate a WMI method
 254  * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 255  * @instance: Instance index
 256  * @method_id: Method ID to call
 257  * &in: Buffer containing input for the method call
 258  * &out: Empty buffer to return the method results
 259  *
 260  * Call an ACPI-WMI method
 261  */
 262 acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
 263 u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
 264 {
 265         struct guid_block *block = NULL;
 266         struct wmi_block *wblock = NULL;
 267         acpi_handle handle;
 268         acpi_status status;
 269         struct acpi_object_list input;
 270         union acpi_object params[3];
 271         char method[4] = "WM";
 272
 273         if (!find_guid(guid_string, &wblock))
 274                 return AE_ERROR;
 275
 276         block = &wblock->gblock;
 277         handle = wblock->handle;
 278
 279         if (!(block->flags & ACPI_WMI_METHOD))
 280                 return AE_BAD_DATA;
 281
 282         if (block->instance_count < instance)
 283                 return AE_BAD_PARAMETER;
 284
 285         input.count = 2;
 286         input.pointer = params;
 287         params[0].type = ACPI_TYPE_INTEGER;
 288         params[0].integer.value = instance;
 289         params[1].type = ACPI_TYPE_INTEGER;
 290         params[1].integer.value = method_id;
 291
 292         if (in) {
 293                 input.count = 3;
 294
 295                 if (block->flags & ACPI_WMI_STRING) {
 296                         params[2].type = ACPI_TYPE_STRING;
 297                 } else {
 298                         params[2].type = ACPI_TYPE_BUFFER;
 299                 }
 300                 params[2].buffer.length = in->length;
 301                 params[2].buffer.pointer = in->pointer;
 302         }
 303
 304         strncat(method, block->object_id, 2);
 305
 306         status = acpi_evaluate_object(handle, method, &input, out);
 307
 308         return status;
 309 }
 310 EXPORT_SYMBOL_GPL(wmi_evaluate_method);
 311
 312 /**
 313  * wmi_query_block - Return contents of a WMI block
 314  * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 315  * @instance: Instance index
 316  * &out: Empty buffer to return the contents of the data block to
 317  *
 318  * Return the contents of an ACPI-WMI data block to a buffer
 319  */
 320 acpi_status wmi_query_block(const char *guid_string, u8 instance,
 321 struct acpi_buffer *out)
 322 {
 323         struct guid_block *block = NULL;
 324         struct wmi_block *wblock = NULL;
 325         acpi_handle handle, wc_handle;
 326         acpi_status status, wc_status = AE_ERROR;
 327         struct acpi_object_list input, wc_input;
 328         union acpi_object wc_params[1], wq_params[1];
 329         char method[4];
 330         char wc_method[4] = "WC";
 331
 332         if (!guid_string || !out)
 333                 return AE_BAD_PARAMETER;
 334
 335         if (!find_guid(guid_string, &wblock))
 336                 return AE_ERROR;
 337
 338         block = &wblock->gblock;
 339         handle = wblock->handle;
 340
 341         if (block->instance_count < instance)
 342                 return AE_BAD_PARAMETER;
 343
 344         /* Check GUID is a data block */
 345         if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
 346                 return AE_ERROR;
 347
 348         input.count = 1;
 349         input.pointer = wq_params;
 350         wq_params[0].type = ACPI_TYPE_INTEGER;
 351         wq_params[0].integer.value = instance;
 352
 353         /*
 354          * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
 355          * enable collection.
 356          */
 357         if (block->flags & ACPI_WMI_EXPENSIVE) {
 358                 wc_input.count = 1;
 359                 wc_input.pointer = wc_params;
 360                 wc_params[0].type = ACPI_TYPE_INTEGER;
 361                 wc_params[0].integer.value = 1;
 362
 363                 strncat(wc_method, block->object_id, 2);
 364
 365                 /*
 366                  * Some GUIDs break the specification by declaring themselves
 367                  * expensive, but have no corresponding WCxx method. So we
 368                  * should not fail if this happens.
 369                  */
 370                 wc_status = acpi_get_handle(handle, wc_method, &wc_handle);
 371                 if (ACPI_SUCCESS(wc_status))
 372                         wc_status = acpi_evaluate_object(handle, wc_method,
 373                                 &wc_input, NULL);
 374         }
 375
 376         strcpy(method, "WQ");
 377         strncat(method, block->object_id, 2);
 378
 379         status = acpi_evaluate_object(handle, method, &input, out);
 380
 381         /*
 382          * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
 383          * the WQxx method failed - we should disable collection anyway.
 384          */
 385         if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
 386                 wc_params[0].integer.value = 0;
 387                 status = acpi_evaluate_object(handle,
 388                 wc_method, &wc_input, NULL);
 389         }
 390
 391         return status;
 392 }
 393 EXPORT_SYMBOL_GPL(wmi_query_block);
 394
 395 /**
 396  * wmi_set_block - Write to a WMI block
 397  * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 398  * @instance: Instance index
 399  * &in: Buffer containing new values for the data block
 400  *
 401  * Write the contents of the input buffer to an ACPI-WMI data block
 402  */
 403 acpi_status wmi_set_block(const char *guid_string, u8 instance,
 404 const struct acpi_buffer *in)
 405 {
 406         struct guid_block *block = NULL;
 407         struct wmi_block *wblock = NULL;
 408         acpi_handle handle;
 409         struct acpi_object_list input;
 410         union acpi_object params[2];
 411         char method[4] = "WS";
 412
 413         if (!guid_string || !in)
 414                 return AE_BAD_DATA;
 415
 416         if (!find_guid(guid_string, &wblock))
 417                 return AE_ERROR;
 418
 419         block = &wblock->gblock;
 420         handle = wblock->handle;
 421
 422         if (block->instance_count < instance)
 423                 return AE_BAD_PARAMETER;
 424
 425         /* Check GUID is a data block */
 426         if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
 427                 return AE_ERROR;
 428
 429         input.count = 2;
 430         input.pointer = params;
 431         params[0].type = ACPI_TYPE_INTEGER;
 432         params[0].integer.value = instance;
 433
 434         if (block->flags & ACPI_WMI_STRING) {
 435                 params[1].type = ACPI_TYPE_STRING;
 436         } else {
 437                 params[1].type = ACPI_TYPE_BUFFER;
 438         }
 439         params[1].buffer.length = in->length;
 440         params[1].buffer.pointer = in->pointer;
 441
 442         strncat(method, block->object_id, 2);
 443
 444         return acpi_evaluate_object(handle, method, &input, NULL);
 445 }
 446 EXPORT_SYMBOL_GPL(wmi_set_block);
 447
 448 /**
 449  * wmi_install_notify_handler - Register handler for WMI events
 450  * @handler: Function to handle notifications
 451  * @data: Data to be returned to handler when event is fired
 452  *
 453  * Register a handler for events sent to the ACPI-WMI mapper device.
 454  */
 455 acpi_status wmi_install_notify_handler(const char *guid,
 456 wmi_notify_handler handler, void *data)
 457 {
 458         struct wmi_block *block;
 459         acpi_status status;
 460
 461         if (!guid || !handler)
 462                 return AE_BAD_PARAMETER;
 463
 464         find_guid(guid, &block);
 465         if (!block)
 466                 return AE_NOT_EXIST;
 467
 468         if (block->handler)
 469                 return AE_ALREADY_ACQUIRED;
 470
 471         block->handler = handler;
 472         block->handler_data = data;
 473
 474         status = wmi_method_enable(block, 1);
 475
 476         return status;
 477 }
 478 EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
 479
 480 /**
 481  * wmi_uninstall_notify_handler - Unregister handler for WMI events
 482  *
 483  * Unregister handler for events sent to the ACPI-WMI mapper device.
 484  */
 485 acpi_status wmi_remove_notify_handler(const char *guid)
 486 {
 487         struct wmi_block *block;
 488         acpi_status status;
 489
 490         if (!guid)
 491                 return AE_BAD_PARAMETER;
 492
 493         find_guid(guid, &block);
 494         if (!block)
 495                 return AE_NOT_EXIST;
 496
 497         if (!block->handler)
 498                 return AE_NULL_ENTRY;
 499
 500         status = wmi_method_enable(block, 0);
 501
 502         block->handler = NULL;
 503         block->handler_data = NULL;
 504
 505         return status;
 506 }
 507 EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
 508
 509 /**
 510  * wmi_get_event_data - Get WMI data associated with an event
 511  *
 512  * @event - Event to find
 513  * &out - Buffer to hold event data
 514  *
 515  * Returns extra data associated with an event in WMI.
 516  */
 517 acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
 518 {
 519         struct acpi_object_list input;
 520         union acpi_object params[1];
 521         struct guid_block *gblock;
 522         struct wmi_block *wblock;
 523         struct list_head *p;
 524
 525         input.count = 1;
 526         input.pointer = params;
 527         params[0].type = ACPI_TYPE_INTEGER;
 528         params[0].integer.value = event;
 529
 530         list_for_each(p, &wmi_blocks.list) {
 531                 wblock = list_entry(p, struct wmi_block, list);
 532                 gblock = &wblock->gblock;
 533
 534                 if ((gblock->flags & ACPI_WMI_EVENT) &&
 535                         (gblock->notify_id == event))
 536                         return acpi_evaluate_object(wblock->handle, "_WED",
 537                                 &input, out);
 538         }
 539
 540         return AE_NOT_FOUND;
 541 }
 542 EXPORT_SYMBOL_GPL(wmi_get_event_data);
 543
 544 /**
 545  * wmi_has_guid - Check if a GUID is available
 546  * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
 547  *
 548  * Check if a given GUID is defined by _WDG
 549  */
 550 bool wmi_has_guid(const char *guid_string)
 551 {
 552         return find_guid(guid_string, NULL);
 553 }
 554 EXPORT_SYMBOL_GPL(wmi_has_guid);
 555
 556 /*
 557  * Parse the _WDG method for the GUID data blocks
 558  */
 559 static __init acpi_status parse_wdg(acpi_handle handle)
 560 {
 561         struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
 562         union acpi_object *obj;
 563         struct guid_block *gblock;
 564         struct wmi_block *wblock;
 565         acpi_status status;
 566         u32 i, total;
 567
 568         status = acpi_evaluate_object(handle, "_WDG", NULL, &out);
 569
 570         if (ACPI_FAILURE(status))
 571                 return status;
 572
 573         obj = (union acpi_object *) out.pointer;
 574
 575         if (obj->type != ACPI_TYPE_BUFFER)
 576                 return AE_ERROR;
 577
 578         total = obj->buffer.length / sizeof(struct guid_block);
 579
 580         gblock = kzalloc(obj->buffer.length, GFP_KERNEL);
 581         if (!gblock)
 582                 return AE_NO_MEMORY;
 583
 584         memcpy(gblock, obj->buffer.pointer, obj->buffer.length);
 585
 586         for (i = 0; i < total; i++) {
 587                 wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
 588                 if (!wblock)
 589                         return AE_NO_MEMORY;
 590
 591                 wblock->gblock = gblock[i];
 592                 wblock->handle = handle;
 593                 list_add_tail(&wblock->list, &wmi_blocks.list);
 594         }
 595
 596         kfree(out.pointer);
 597         kfree(gblock);
 598
 599         return status;
 600 }
 601
 602 /*
 603  * WMI can have EmbeddedControl access regions. In which case, we just want to
 604  * hand these off to the EC driver.
 605  */
 606 static acpi_status
 607 acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
 608                       u32 bits, acpi_integer * value,
 609                       void *handler_context, void *region_context)
 610 {
 611         int result = 0, i = 0;
 612         u8 temp = 0;
 613
 614         if ((address > 0xFF) || !value)
 615                 return AE_BAD_PARAMETER;
 616
 617         if (function != ACPI_READ && function != ACPI_WRITE)
 618                 return AE_BAD_PARAMETER;
 619
 620         if (bits != 8)
 621                 return AE_BAD_PARAMETER;
 622
 623         if (function == ACPI_READ) {
 624                 result = ec_read(address, &temp);
 625                 (*value) |= ((acpi_integer)temp) << i;
 626         } else {
 627                 temp = 0xff & ((*value) >> i);
 628                 result = ec_write(address, temp);
 629         }
 630
 631         switch (result) {
 632         case -EINVAL:
 633                 return AE_BAD_PARAMETER;
 634                 break;
 635         case -ENODEV:
 636                 return AE_NOT_FOUND;
 637                 break;
 638         case -ETIME:
 639                 return AE_TIME;
 640                 break;
 641         default:
 642                 return AE_OK;
 643         }
 644 }
 645
 646 static void acpi_wmi_notify(acpi_handle handle, u32 event, void *data)
 647 {
 648         struct guid_block *block;
 649         struct wmi_block *wblock;
 650         struct list_head *p;
 651         struct acpi_device *device = data;
 652
 653         list_for_each(p, &wmi_blocks.list) {
 654                 wblock = list_entry(p, struct wmi_block, list);
 655                 block = &wblock->gblock;
 656
 657                 if ((block->flags & ACPI_WMI_EVENT) &&
 658                         (block->notify_id == event)) {
 659                         if (wblock->handler)
 660                                 wblock->handler(event, wblock->handler_data);
 661
 662                         acpi_bus_generate_netlink_event(
 663                                 device->pnp.device_class, dev_name(&device->dev),
 664                                 event, 0);
 665                         break;
 666                 }
 667         }
 668 }
 669
 670 static int acpi_wmi_remove(struct acpi_device *device, int type)
 671 {
 672         acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 673                 acpi_wmi_notify);
 674
 675         acpi_remove_address_space_handler(device->handle,
 676                                 ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
 677
 678         return 0;
 679 }
 680
 681 static int __init acpi_wmi_add(struct acpi_device *device)
 682 {
 683         acpi_status status;
 684         int result = 0;
 685
 686         status = acpi_install_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 687                 acpi_wmi_notify, device);
 688         if (ACPI_FAILURE(status)) {
 689                 printk(KERN_ERR PREFIX "Error installing notify handler\n");
 690                 return -ENODEV;
 691         }
 692
 693         status = acpi_install_address_space_handler(device->handle,
 694                                                     ACPI_ADR_SPACE_EC,
 695                                                     &acpi_wmi_ec_space_handler,
 696                                                     NULL, NULL);
 697         if (ACPI_FAILURE(status))
 698                 return -ENODEV;
 699
 700         status = parse_wdg(device->handle);
 701         if (ACPI_FAILURE(status)) {
 702                 printk(KERN_ERR PREFIX "Error installing EC region handler\n");
 703                 return -ENODEV;
 704         }
 705
 706         return result;
 707 }
 708
 709 static int __init acpi_wmi_init(void)
 710 {
 711         acpi_status result;
 712
 713         INIT_LIST_HEAD(&wmi_blocks.list);
 714
 715         if (acpi_disabled)
 716                 return -ENODEV;
 717
 718         result = acpi_bus_register_driver(&acpi_wmi_driver);
 719
 720         if (result < 0) {
 721                 printk(KERN_INFO PREFIX "Error loading mapper\n");
 722         } else {
 723                 printk(KERN_INFO PREFIX "Mapper loaded\n");
 724         }
 725
 726         return result;
 727 }
 728
 729 static void __exit acpi_wmi_exit(void)
 730 {
 731         struct list_head *p, *tmp;
 732         struct wmi_block *wblock;
 733
 734         acpi_bus_unregister_driver(&acpi_wmi_driver);
 735
 736         list_for_each_safe(p, tmp, &wmi_blocks.list) {
 737                 wblock = list_entry(p, struct wmi_block, list);
 738
 739                 list_del(p);
 740                 kfree(wblock);
 741         }
 742
 743         printk(KERN_INFO PREFIX "Mapper unloaded\n");
 744 }
 745
 746 subsys_initcall(acpi_wmi_init);
 747 module_exit(acpi_wmi_exit);