drivers/acpi/utils.c

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