drivers/acpi/utils.c

   1 /*
   2  *  acpi_utils.c - ACPI Utility Functions ($Revision: 10 $)
   3  *
   4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   6  *
   7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License as published by
  11  *  the Free Software Foundation; either version 2 of the License, or (at
  12  *  your option) any later version.
  13  *
  14  *  This program is distributed in the hope that it will be useful, but
  15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  *  General Public License for more details.
  18  *
  19  *  You should have received a copy of the GNU General Public License along
  20  *  with this program; if not, write to the Free Software Foundation, Inc.,
  21  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  22  *
  23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  24  */
  25
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28 #include <linux/slab.h>
  29 #include <linux/init.h>
  30 #include <linux/types.h>
  31 #include <linux/hardirq.h>
  32 #include <linux/acpi.h>
  33
  34 #include "internal.h"
  35
  36 #define _COMPONENT              ACPI_BUS_COMPONENT
  37 ACPI_MODULE_NAME("utils");
  38
  39 /* --------------------------------------------------------------------------
  40                             Object Evaluation Helpers
  41    -------------------------------------------------------------------------- */
  42 static void
  43 acpi_util_eval_error(acpi_handle h, acpi_string p, acpi_status s)
  44 {
  45 #ifdef ACPI_DEBUG_OUTPUT
  46         char prefix[80] = {'\0'};
  47         struct acpi_buffer buffer = {sizeof(prefix), prefix};
  48         acpi_get_name(h, ACPI_FULL_PATHNAME, &buffer);
  49         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluate [%s.%s]: %s\n",
  50                 (char *) prefix, p, acpi_format_exception(s)));
  51 #else
  52         return;
  53 #endif
  54 }
  55
  56 acpi_status
  57 acpi_extract_package(union acpi_object *package,
  58                      struct acpi_buffer *format, struct acpi_buffer *buffer)
  59 {
  60         u32 size_required = 0;
  61         u32 tail_offset = 0;
  62         char *format_string = NULL;
  63         u32 format_count = 0;
  64         u32 i = 0;
  65         u8 *head = NULL;
  66         u8 *tail = NULL;
  67
  68
  69         if (!package || (package->type != ACPI_TYPE_PACKAGE)
  70             || (package->package.count < 1)) {
  71                 printk(KERN_WARNING PREFIX "Invalid package argument\n");
  72                 return AE_BAD_PARAMETER;
  73         }
  74
  75         if (!format || !format->pointer || (format->length < 1)) {
  76                 printk(KERN_WARNING PREFIX "Invalid format argument\n");
  77                 return AE_BAD_PARAMETER;
  78         }
  79
  80         if (!buffer) {
  81                 printk(KERN_WARNING PREFIX "Invalid buffer argument\n");
  82                 return AE_BAD_PARAMETER;
  83         }
  84
  85         format_count = (format->length / sizeof(char)) - 1;
  86         if (format_count > package->package.count) {
  87                 printk(KERN_WARNING PREFIX "Format specifies more objects [%d]"
  88                               " than exist in package [%d].\n",
  89                               format_count, package->package.count);
  90                 return AE_BAD_DATA;
  91         }
  92
  93         format_string = format->pointer;
  94
  95         /*
  96          * Calculate size_required.
  97          */
  98         for (i = 0; i < format_count; i++) {
  99
 100                 union acpi_object *element = &(package->package.elements[i]);
 101
 102                 if (!element) {
 103                         return AE_BAD_DATA;
 104                 }
 105
 106                 switch (element->type) {
 107
 108                 case ACPI_TYPE_INTEGER:
 109                         switch (format_string[i]) {
 110                         case 'N':
 111                                 size_required += sizeof(u64);
 112                                 tail_offset += sizeof(u64);
 113                                 break;
 114                         case 'S':
 115                                 size_required +=
 116                                     sizeof(char *) + sizeof(u64) +
 117                                     sizeof(char);
 118                                 tail_offset += sizeof(char *);
 119                                 break;
 120                         default:
 121                                 printk(KERN_WARNING PREFIX "Invalid package element"
 122                                               " [%d]: got number, expecting"
 123                                               " [%c]\n",
 124                                               i, format_string[i]);
 125                                 return AE_BAD_DATA;
 126                                 break;
 127                         }
 128                         break;
 129
 130                 case ACPI_TYPE_STRING:
 131                 case ACPI_TYPE_BUFFER:
 132                         switch (format_string[i]) {
 133                         case 'S':
 134                                 size_required +=
 135                                     sizeof(char *) +
 136                                     (element->string.length * sizeof(char)) +
 137                                     sizeof(char);
 138                                 tail_offset += sizeof(char *);
 139                                 break;
 140                         case 'B':
 141                                 size_required +=
 142                                     sizeof(u8 *) +
 143                                     (element->buffer.length * sizeof(u8));
 144                                 tail_offset += sizeof(u8 *);
 145                                 break;
 146                         default:
 147                                 printk(KERN_WARNING PREFIX "Invalid package element"
 148                                               " [%d] got string/buffer,"
 149                                               " expecting [%c]\n",
 150                                               i, format_string[i]);
 151                                 return AE_BAD_DATA;
 152                                 break;
 153                         }
 154                         break;
 155
 156                 case ACPI_TYPE_PACKAGE:
 157                 default:
 158                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 159                                           "Found unsupported element at index=%d\n",
 160                                           i));
 161                         /* TBD: handle nested packages... */
 162                         return AE_SUPPORT;
 163                         break;
 164                 }
 165         }
 166
 167         /*
 168          * Validate output buffer.
 169          */
 170         if (buffer->length == ACPI_ALLOCATE_BUFFER) {
 171                 buffer->pointer = ACPI_ALLOCATE(size_required);
 172                 if (!buffer->pointer)
 173                         return AE_NO_MEMORY;
 174                 buffer->length = size_required;
 175                 memset(buffer->pointer, 0, size_required);
 176         } else {
 177                 if (buffer->length < size_required) {
 178                         buffer->length = size_required;
 179                         return AE_BUFFER_OVERFLOW;
 180                 } else if (buffer->length != size_required ||
 181                            !buffer->pointer) {
 182                         return AE_BAD_PARAMETER;
 183                 }
 184         }
 185
 186         head = buffer->pointer;
 187         tail = buffer->pointer + tail_offset;
 188
 189         /*
 190          * Extract package data.
 191          */
 192         for (i = 0; i < format_count; i++) {
 193
 194                 u8 **pointer = NULL;
 195                 union acpi_object *element = &(package->package.elements[i]);
 196
 197                 if (!element) {
 198                         return AE_BAD_DATA;
 199                 }
 200
 201                 switch (element->type) {
 202
 203                 case ACPI_TYPE_INTEGER:
 204                         switch (format_string[i]) {
 205                         case 'N':
 206                                 *((u64 *) head) =
 207                                     element->integer.value;
 208                                 head += sizeof(u64);
 209                                 break;
 210                         case 'S':
 211                                 pointer = (u8 **) head;
 212                                 *pointer = tail;
 213                                 *((u64 *) tail) =
 214                                     element->integer.value;
 215                                 head += sizeof(u64 *);
 216                                 tail += sizeof(u64);
 217                                 /* NULL terminate string */
 218                                 *tail = (char)0;
 219                                 tail += sizeof(char);
 220                                 break;
 221                         default:
 222                                 /* Should never get here */
 223                                 break;
 224                         }
 225                         break;
 226
 227                 case ACPI_TYPE_STRING:
 228                 case ACPI_TYPE_BUFFER:
 229                         switch (format_string[i]) {
 230                         case 'S':
 231                                 pointer = (u8 **) head;
 232                                 *pointer = tail;
 233                                 memcpy(tail, element->string.pointer,
 234                                        element->string.length);
 235                                 head += sizeof(char *);
 236                                 tail += element->string.length * sizeof(char);
 237                                 /* NULL terminate string */
 238                                 *tail = (char)0;
 239                                 tail += sizeof(char);
 240                                 break;
 241                         case 'B':
 242                                 pointer = (u8 **) head;
 243                                 *pointer = tail;
 244                                 memcpy(tail, element->buffer.pointer,
 245                                        element->buffer.length);
 246                                 head += sizeof(u8 *);
 247                                 tail += element->buffer.length * sizeof(u8);
 248                                 break;
 249                         default:
 250                                 /* Should never get here */
 251                                 break;
 252                         }
 253                         break;
 254
 255                 case ACPI_TYPE_PACKAGE:
 256                         /* TBD: handle nested packages... */
 257                 default:
 258                         /* Should never get here */
 259                         break;
 260                 }
 261         }
 262
 263         return AE_OK;
 264 }
 265
 266 EXPORT_SYMBOL(acpi_extract_package);
 267
 268 acpi_status
 269 acpi_evaluate_integer(acpi_handle handle,
 270                       acpi_string pathname,
 271                       struct acpi_object_list *arguments, unsigned long long *data)
 272 {
 273         acpi_status status = AE_OK;
 274         union acpi_object element;
 275         struct acpi_buffer buffer = { 0, NULL };
 276
 277         if (!data)
 278                 return AE_BAD_PARAMETER;
 279
 280         buffer.length = sizeof(union acpi_object);
 281         buffer.pointer = &element;
 282         status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
 283         if (ACPI_FAILURE(status)) {
 284                 acpi_util_eval_error(handle, pathname, status);
 285                 return status;
 286         }
 287
 288         if (element.type != ACPI_TYPE_INTEGER) {
 289                 acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
 290                 return AE_BAD_DATA;
 291         }
 292
 293         *data = element.integer.value;
 294
 295         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data));
 296
 297         return AE_OK;
 298 }
 299
 300 EXPORT_SYMBOL(acpi_evaluate_integer);
 301
 302 acpi_status
 303 acpi_evaluate_reference(acpi_handle handle,
 304                         acpi_string pathname,
 305                         struct acpi_object_list *arguments,
 306                         struct acpi_handle_list *list)
 307 {
 308         acpi_status status = AE_OK;
 309         union acpi_object *package = NULL;
 310         union acpi_object *element = NULL;
 311         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 312         u32 i = 0;
 313
 314
 315         if (!list) {
 316                 return AE_BAD_PARAMETER;
 317         }
 318
 319         /* Evaluate object. */
 320
 321         status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
 322         if (ACPI_FAILURE(status))
 323                 goto end;
 324
 325         package = buffer.pointer;
 326
 327         if ((buffer.length == 0) || !package) {
 328                 printk(KERN_ERR PREFIX "No return object (len %X ptr %p)\n",
 329                             (unsigned)buffer.length, package);
 330                 status = AE_BAD_DATA;
 331                 acpi_util_eval_error(handle, pathname, status);
 332                 goto end;
 333         }
 334         if (package->type != ACPI_TYPE_PACKAGE) {
 335                 printk(KERN_ERR PREFIX "Expecting a [Package], found type %X\n",
 336                             package->type);
 337                 status = AE_BAD_DATA;
 338                 acpi_util_eval_error(handle, pathname, status);
 339                 goto end;
 340         }
 341         if (!package->package.count) {
 342                 printk(KERN_ERR PREFIX "[Package] has zero elements (%p)\n",
 343                             package);
 344                 status = AE_BAD_DATA;
 345                 acpi_util_eval_error(handle, pathname, status);
 346                 goto end;
 347         }
 348
 349         if (package->package.count > ACPI_MAX_HANDLES) {
 350                 return AE_NO_MEMORY;
 351         }
 352         list->count = package->package.count;
 353
 354         /* Extract package data. */
 355
 356         for (i = 0; i < list->count; i++) {
 357
 358                 element = &(package->package.elements[i]);
 359
 360                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
 361                         status = AE_BAD_DATA;
 362                         printk(KERN_ERR PREFIX
 363                                     "Expecting a [Reference] package element, found type %X\n",
 364                                     element->type);
 365                         acpi_util_eval_error(handle, pathname, status);
 366                         break;
 367                 }
 368
 369                 if (!element->reference.handle) {
 370                         printk(KERN_WARNING PREFIX "Invalid reference in"
 371                                " package %s\n", pathname);
 372                         status = AE_NULL_ENTRY;
 373                         break;
 374                 }
 375                 /* Get the  acpi_handle. */
 376
 377                 list->handles[i] = element->reference.handle;
 378                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
 379                                   list->handles[i]));
 380         }
 381
 382       end:
 383         if (ACPI_FAILURE(status)) {
 384                 list->count = 0;
 385                 //kfree(list->handles);
 386         }
 387
 388         kfree(buffer.pointer);
 389
 390         return status;
 391 }
 392
 393 EXPORT_SYMBOL(acpi_evaluate_reference);
 394
 395 acpi_status
 396 acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld)
 397 {
 398         acpi_status status;
 399         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 400         union acpi_object *output;
 401
 402         status = acpi_evaluate_object(handle, "_PLD", NULL, &buffer);
 403
 404         if (ACPI_FAILURE(status))
 405                 return status;
 406
 407         output = buffer.pointer;
 408
 409         if (!output || output->type != ACPI_TYPE_PACKAGE
 410             || !output->package.count
 411             || output->package.elements[0].type != ACPI_TYPE_BUFFER
 412             || output->package.elements[0].buffer.length < ACPI_PLD_REV1_BUFFER_SIZE) {
 413                 status = AE_TYPE;
 414                 goto out;
 415         }
 416
 417         status = acpi_decode_pld_buffer(
 418                         output->package.elements[0].buffer.pointer,
 419                         output->package.elements[0].buffer.length,
 420                         pld);
 421
 422 out:
 423         kfree(buffer.pointer);
 424         return status;
 425 }
 426 EXPORT_SYMBOL(acpi_get_physical_device_location);
 427
 428 /**
 429  * acpi_evaluate_hotplug_ost: Evaluate _OST for hotplug operations
 430  * @handle: ACPI device handle
 431  * @source_event: source event code
 432  * @status_code: status code
 433  * @status_buf: optional detailed information (NULL if none)
 434  *
 435  * Evaluate _OST for hotplug operations. All ACPI hotplug handlers
 436  * must call this function when evaluating _OST for hotplug operations.
 437  * When the platform does not support _OST, this function has no effect.
 438  */
 439 acpi_status
 440 acpi_evaluate_hotplug_ost(acpi_handle handle, u32 source_event,
 441                 u32 status_code, struct acpi_buffer *status_buf)
 442 {
 443 #ifdef ACPI_HOTPLUG_OST
 444         union acpi_object params[3] = {
 445                 {.type = ACPI_TYPE_INTEGER,},
 446                 {.type = ACPI_TYPE_INTEGER,},
 447                 {.type = ACPI_TYPE_BUFFER,}
 448         };
 449         struct acpi_object_list arg_list = {3, params};
 450         acpi_status status;
 451
 452         params[0].integer.value = source_event;
 453         params[1].integer.value = status_code;
 454         if (status_buf != NULL) {
 455                 params[2].buffer.pointer = status_buf->pointer;
 456                 params[2].buffer.length = status_buf->length;
 457         } else {
 458                 params[2].buffer.pointer = NULL;
 459                 params[2].buffer.length = 0;
 460         }
 461
 462         status = acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
 463         return status;
 464 #else
 465         return AE_OK;
 466 #endif
 467 }
 468 EXPORT_SYMBOL(acpi_evaluate_hotplug_ost);
 469
 470 /**
 471  * acpi_handle_printk: Print message with ACPI prefix and object path
 472  *
 473  * This function is called through acpi_handle_<level> macros and prints
 474  * a message with ACPI prefix and object path.  This function acquires
 475  * the global namespace mutex to obtain an object path.  In interrupt
 476  * context, it shows the object path as <n/a>.
 477  */
 478 void
 479 acpi_handle_printk(const char *level, acpi_handle handle, const char *fmt, ...)
 480 {
 481         struct va_format vaf;
 482         va_list args;
 483         struct acpi_buffer buffer = {
 484                 .length = ACPI_ALLOCATE_BUFFER,
 485                 .pointer = NULL
 486         };
 487         const char *path;
 488
 489         va_start(args, fmt);
 490         vaf.fmt = fmt;
 491         vaf.va = &args;
 492
 493         if (in_interrupt() ||
 494             acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer) != AE_OK)
 495                 path = "<n/a>";
 496         else
 497                 path = buffer.pointer;
 498
 499         printk("%sACPI: %s: %pV", level, path, &vaf);
 500
 501         va_end(args);
 502         kfree(buffer.pointer);
 503 }
 504 EXPORT_SYMBOL(acpi_handle_printk);
 505
 506 /**
 507  * acpi_has_method: Check whether @handle has a method named @name
 508  * @handle: ACPI device handle
 509  * @name: name of object or method
 510  *
 511  * Check whether @handle has a method named @name.
 512  */
 513 bool acpi_has_method(acpi_handle handle, char *name)
 514 {
 515         acpi_handle tmp;
 516
 517         return ACPI_SUCCESS(acpi_get_handle(handle, name, &tmp));
 518 }
 519 EXPORT_SYMBOL(acpi_has_method);
 520
 521 acpi_status acpi_execute_simple_method(acpi_handle handle, char *method,
 522                                        u64 arg)
 523 {
 524         union acpi_object obj = { .type = ACPI_TYPE_INTEGER };
 525         struct acpi_object_list arg_list = { .count = 1, .pointer = &obj, };
 526
 527         obj.integer.value = arg;
 528
 529         return acpi_evaluate_object(handle, method, &arg_list, NULL);
 530 }
 531 EXPORT_SYMBOL(acpi_execute_simple_method);
 532
 533 /**
 534  * acpi_evaluate_ej0: Evaluate _EJ0 method for hotplug operations
 535  * @handle: ACPI device handle
 536  *
 537  * Evaluate device's _EJ0 method for hotplug operations.
 538  */
 539 acpi_status acpi_evaluate_ej0(acpi_handle handle)
 540 {
 541         acpi_status status;
 542
 543         status = acpi_execute_simple_method(handle, "_EJ0", 1);
 544         if (status == AE_NOT_FOUND)
 545                 acpi_handle_warn(handle, "No _EJ0 support for device\n");
 546         else if (ACPI_FAILURE(status))
 547                 acpi_handle_warn(handle, "Eject failed (0x%x)\n", status);
 548
 549         return status;
 550 }
 551
 552 /**
 553  * acpi_evaluate_lck: Evaluate _LCK method to lock/unlock device
 554  * @handle: ACPI device handle
 555  * @lock: lock device if non-zero, otherwise unlock device
 556  *
 557  * Evaluate device's _LCK method if present to lock/unlock device
 558  */
 559 acpi_status acpi_evaluate_lck(acpi_handle handle, int lock)
 560 {
 561         acpi_status status;
 562
 563         status = acpi_execute_simple_method(handle, "_LCK", !!lock);
 564         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 565                 if (lock)
 566                         acpi_handle_warn(handle,
 567                                 "Locking device failed (0x%x)\n", status);
 568                 else
 569                         acpi_handle_warn(handle,
 570                                 "Unlocking device failed (0x%x)\n", status);
 571         }
 572
 573         return status;
 574 }
 575
 576 /**
 577  * acpi_evaluate_dsm - evaluate device's _DSM method
 578  * @handle: ACPI device handle
 579  * @uuid: UUID of requested functions, should be 16 bytes
 580  * @rev: revision number of requested function
 581  * @func: requested function number
 582  * @argv4: the function specific parameter
 583  *
 584  * Evaluate device's _DSM method with specified UUID, revision id and
 585  * function number. Caller needs to free the returned object.
 586  *
 587  * Though ACPI defines the fourth parameter for _DSM should be a package,
 588  * some old BIOSes do expect a buffer or an integer etc.
 589  */
 590 union acpi_object *
 591 acpi_evaluate_dsm(acpi_handle handle, const u8 *uuid, int rev, int func,
 592                   union acpi_object *argv4)
 593 {
 594         acpi_status ret;
 595         struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
 596         union acpi_object params[4];
 597         struct acpi_object_list input = {
 598                 .count = 4,
 599                 .pointer = params,
 600         };
 601
 602         params[0].type = ACPI_TYPE_BUFFER;
 603         params[0].buffer.length = 16;
 604         params[0].buffer.pointer = (char *)uuid;
 605         params[1].type = ACPI_TYPE_INTEGER;
 606         params[1].integer.value = rev;
 607         params[2].type = ACPI_TYPE_INTEGER;
 608         params[2].integer.value = func;
 609         if (argv4) {
 610                 params[3] = *argv4;
 611         } else {
 612                 params[3].type = ACPI_TYPE_PACKAGE;
 613                 params[3].package.count = 0;
 614                 params[3].package.elements = NULL;
 615         }
 616
 617         ret = acpi_evaluate_object(handle, "_DSM", &input, &buf);
 618         if (ACPI_SUCCESS(ret))
 619                 return (union acpi_object *)buf.pointer;
 620
 621         if (ret != AE_NOT_FOUND)
 622                 acpi_handle_warn(handle,
 623                                 "failed to evaluate _DSM (0x%x)\n", ret);
 624
 625         return NULL;
 626 }
 627 EXPORT_SYMBOL(acpi_evaluate_dsm);
 628
 629 /**
 630  * acpi_check_dsm - check if _DSM method supports requested functions.
 631  * @handle: ACPI device handle
 632  * @uuid: UUID of requested functions, should be 16 bytes at least
 633  * @rev: revision number of requested functions
 634  * @funcs: bitmap of requested functions
 635  * @exclude: excluding special value, used to support i915 and nouveau
 636  *
 637  * Evaluate device's _DSM method to check whether it supports requested
 638  * functions. Currently only support 64 functions at maximum, should be
 639  * enough for now.
 640  */
 641 bool acpi_check_dsm(acpi_handle handle, const u8 *uuid, int rev, u64 funcs)
 642 {
 643         int i;
 644         u64 mask = 0;
 645         union acpi_object *obj;
 646
 647         if (funcs == 0)
 648                 return false;
 649
 650         obj = acpi_evaluate_dsm(handle, uuid, rev, 0, NULL);
 651         if (!obj)
 652                 return false;
 653
 654         /* For compatibility, old BIOSes may return an integer */
 655         if (obj->type == ACPI_TYPE_INTEGER)
 656                 mask = obj->integer.value;
 657         else if (obj->type == ACPI_TYPE_BUFFER)
 658                 for (i = 0; i < obj->buffer.length && i < 8; i++)
 659                         mask |= (((u8)obj->buffer.pointer[i]) << (i * 8));
 660         ACPI_FREE(obj);
 661
 662         /*
 663          * Bit 0 indicates whether there's support for any functions other than
 664          * function 0 for the specified UUID and revision.
 665          */
 666         if ((mask & 0x1) && (mask & funcs) == funcs)
 667                 return true;
 668
 669         return false;
 670 }
 671 EXPORT_SYMBOL(acpi_check_dsm);