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                 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(size_required);
 168                 if (!buffer->pointer)
 169                         return AE_NO_MEMORY;
 170                 buffer->length = size_required;
 171                 memset(buffer->pointer, 0, size_required);
 172         } else {
 173                 if (buffer->length < size_required) {
 174                         buffer->length = size_required;
 175                         return AE_BUFFER_OVERFLOW;
 176                 } else if (buffer->length != size_required ||
 177                            !buffer->pointer) {
 178                         return AE_BAD_PARAMETER;
 179                 }
 180         }
 181
 182         head = buffer->pointer;
 183         tail = buffer->pointer + tail_offset;
 184
 185         /*
 186          * Extract package data.
 187          */
 188         for (i = 0; i < format_count; i++) {
 189
 190                 u8 **pointer = NULL;
 191                 union acpi_object *element = &(package->package.elements[i]);
 192
 193                 if (!element) {
 194                         return AE_BAD_DATA;
 195                 }
 196
 197                 switch (element->type) {
 198
 199                 case ACPI_TYPE_INTEGER:
 200                         switch (format_string[i]) {
 201                         case 'N':
 202                                 *((u64 *) head) =
 203                                     element->integer.value;
 204                                 head += sizeof(u64);
 205                                 break;
 206                         case 'S':
 207                                 pointer = (u8 **) head;
 208                                 *pointer = tail;
 209                                 *((u64 *) tail) =
 210                                     element->integer.value;
 211                                 head += sizeof(u64 *);
 212                                 tail += sizeof(u64);
 213                                 /* NULL terminate string */
 214                                 *tail = (char)0;
 215                                 tail += sizeof(char);
 216                                 break;
 217                         default:
 218                                 /* Should never get here */
 219                                 break;
 220                         }
 221                         break;
 222
 223                 case ACPI_TYPE_STRING:
 224                 case ACPI_TYPE_BUFFER:
 225                         switch (format_string[i]) {
 226                         case 'S':
 227                                 pointer = (u8 **) head;
 228                                 *pointer = tail;
 229                                 memcpy(tail, element->string.pointer,
 230                                        element->string.length);
 231                                 head += sizeof(char *);
 232                                 tail += element->string.length * sizeof(char);
 233                                 /* NULL terminate string */
 234                                 *tail = (char)0;
 235                                 tail += sizeof(char);
 236                                 break;
 237                         case 'B':
 238                                 pointer = (u8 **) head;
 239                                 *pointer = tail;
 240                                 memcpy(tail, element->buffer.pointer,
 241                                        element->buffer.length);
 242                                 head += sizeof(u8 *);
 243                                 tail += element->buffer.length * sizeof(u8);
 244                                 break;
 245                         default:
 246                                 /* Should never get here */
 247                                 break;
 248                         }
 249                         break;
 250
 251                 case ACPI_TYPE_PACKAGE:
 252                         /* TBD: handle nested packages... */
 253                 default:
 254                         /* Should never get here */
 255                         break;
 256                 }
 257         }
 258
 259         return AE_OK;
 260 }
 261
 262 EXPORT_SYMBOL(acpi_extract_package);
 263
 264 acpi_status
 265 acpi_evaluate_integer(acpi_handle handle,
 266                       acpi_string pathname,
 267                       struct acpi_object_list *arguments, unsigned long long *data)
 268 {
 269         acpi_status status = AE_OK;
 270         union acpi_object element;
 271         struct acpi_buffer buffer = { 0, NULL };
 272
 273         if (!data)
 274                 return AE_BAD_PARAMETER;
 275
 276         buffer.length = sizeof(union acpi_object);
 277         buffer.pointer = &element;
 278         status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
 279         if (ACPI_FAILURE(status)) {
 280                 acpi_util_eval_error(handle, pathname, status);
 281                 return status;
 282         }
 283
 284         if (element.type != ACPI_TYPE_INTEGER) {
 285                 acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
 286                 return AE_BAD_DATA;
 287         }
 288
 289         *data = element.integer.value;
 290
 291         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data));
 292
 293         return AE_OK;
 294 }
 295
 296 EXPORT_SYMBOL(acpi_evaluate_integer);
 297
 298 acpi_status
 299 acpi_evaluate_reference(acpi_handle handle,
 300                         acpi_string pathname,
 301                         struct acpi_object_list *arguments,
 302                         struct acpi_handle_list *list)
 303 {
 304         acpi_status status = AE_OK;
 305         union acpi_object *package = NULL;
 306         union acpi_object *element = NULL;
 307         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 308         u32 i = 0;
 309
 310
 311         if (!list) {
 312                 return AE_BAD_PARAMETER;
 313         }
 314
 315         /* Evaluate object. */
 316
 317         status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
 318         if (ACPI_FAILURE(status))
 319                 goto end;
 320
 321         package = buffer.pointer;
 322
 323         if ((buffer.length == 0) || !package) {
 324                 printk(KERN_ERR PREFIX "No return object (len %X ptr %p)\n",
 325                             (unsigned)buffer.length, package);
 326                 status = AE_BAD_DATA;
 327                 acpi_util_eval_error(handle, pathname, status);
 328                 goto end;
 329         }
 330         if (package->type != ACPI_TYPE_PACKAGE) {
 331                 printk(KERN_ERR PREFIX "Expecting a [Package], found type %X\n",
 332                             package->type);
 333                 status = AE_BAD_DATA;
 334                 acpi_util_eval_error(handle, pathname, status);
 335                 goto end;
 336         }
 337         if (!package->package.count) {
 338                 printk(KERN_ERR PREFIX "[Package] has zero elements (%p)\n",
 339                             package);
 340                 status = AE_BAD_DATA;
 341                 acpi_util_eval_error(handle, pathname, status);
 342                 goto end;
 343         }
 344
 345         if (package->package.count > ACPI_MAX_HANDLES) {
 346                 return AE_NO_MEMORY;
 347         }
 348         list->count = package->package.count;
 349
 350         /* Extract package data. */
 351
 352         for (i = 0; i < list->count; i++) {
 353
 354                 element = &(package->package.elements[i]);
 355
 356                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
 357                         status = AE_BAD_DATA;
 358                         printk(KERN_ERR PREFIX
 359                                     "Expecting a [Reference] package element, found type %X\n",
 360                                     element->type);
 361                         acpi_util_eval_error(handle, pathname, status);
 362                         break;
 363                 }
 364
 365                 if (!element->reference.handle) {
 366                         printk(KERN_WARNING PREFIX "Invalid reference in"
 367                                " package %s\n", pathname);
 368                         status = AE_NULL_ENTRY;
 369                         break;
 370                 }
 371                 /* Get the  acpi_handle. */
 372
 373                 list->handles[i] = element->reference.handle;
 374                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
 375                                   list->handles[i]));
 376         }
 377
 378       end:
 379         if (ACPI_FAILURE(status)) {
 380                 list->count = 0;
 381                 //kfree(list->handles);
 382         }
 383
 384         kfree(buffer.pointer);
 385
 386         return status;
 387 }
 388
 389 EXPORT_SYMBOL(acpi_evaluate_reference);
 390
 391 acpi_status
 392 acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld)
 393 {
 394         acpi_status status;
 395         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 396         union acpi_object *output;
 397
 398         status = acpi_evaluate_object(handle, "_PLD", NULL, &buffer);
 399
 400         if (ACPI_FAILURE(status))
 401                 return status;
 402
 403         output = buffer.pointer;
 404
 405         if (!output || output->type != ACPI_TYPE_PACKAGE
 406             || !output->package.count
 407             || output->package.elements[0].type != ACPI_TYPE_BUFFER
 408             || output->package.elements[0].buffer.length < ACPI_PLD_REV1_BUFFER_SIZE) {
 409                 status = AE_TYPE;
 410                 goto out;
 411         }
 412
 413         status = acpi_decode_pld_buffer(
 414                         output->package.elements[0].buffer.pointer,
 415                         output->package.elements[0].buffer.length,
 416                         pld);
 417
 418 out:
 419         kfree(buffer.pointer);
 420         return status;
 421 }
 422 EXPORT_SYMBOL(acpi_get_physical_device_location);
 423
 424 /**
 425  * acpi_evaluate_hotplug_ost: Evaluate _OST for hotplug operations
 426  * @handle: ACPI device handle
 427  * @source_event: source event code
 428  * @status_code: status code
 429  * @status_buf: optional detailed information (NULL if none)
 430  *
 431  * Evaluate _OST for hotplug operations. All ACPI hotplug handlers
 432  * must call this function when evaluating _OST for hotplug operations.
 433  * When the platform does not support _OST, this function has no effect.
 434  */
 435 acpi_status
 436 acpi_evaluate_hotplug_ost(acpi_handle handle, u32 source_event,
 437                 u32 status_code, struct acpi_buffer *status_buf)
 438 {
 439 #ifdef ACPI_HOTPLUG_OST
 440         union acpi_object params[3] = {
 441                 {.type = ACPI_TYPE_INTEGER,},
 442                 {.type = ACPI_TYPE_INTEGER,},
 443                 {.type = ACPI_TYPE_BUFFER,}
 444         };
 445         struct acpi_object_list arg_list = {3, params};
 446         acpi_status status;
 447
 448         params[0].integer.value = source_event;
 449         params[1].integer.value = status_code;
 450         if (status_buf != NULL) {
 451                 params[2].buffer.pointer = status_buf->pointer;
 452                 params[2].buffer.length = status_buf->length;
 453         } else {
 454                 params[2].buffer.pointer = NULL;
 455                 params[2].buffer.length = 0;
 456         }
 457
 458         status = acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
 459         return status;
 460 #else
 461         return AE_OK;
 462 #endif
 463 }
 464 EXPORT_SYMBOL(acpi_evaluate_hotplug_ost);
 465
 466 /**
 467  * acpi_handle_printk: Print message with ACPI prefix and object path
 468  *
 469  * This function is called through acpi_handle_<level> macros and prints
 470  * a message with ACPI prefix and object path.  This function acquires
 471  * the global namespace mutex to obtain an object path.  In interrupt
 472  * context, it shows the object path as <n/a>.
 473  */
 474 void
 475 acpi_handle_printk(const char *level, acpi_handle handle, const char *fmt, ...)
 476 {
 477         struct va_format vaf;
 478         va_list args;
 479         struct acpi_buffer buffer = {
 480                 .length = ACPI_ALLOCATE_BUFFER,
 481                 .pointer = NULL
 482         };
 483         const char *path;
 484
 485         va_start(args, fmt);
 486         vaf.fmt = fmt;
 487         vaf.va = &args;
 488
 489         if (in_interrupt() ||
 490             acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer) != AE_OK)
 491                 path = "<n/a>";
 492         else
 493                 path = buffer.pointer;
 494
 495         printk("%sACPI: %s: %pV", level, path, &vaf);
 496
 497         va_end(args);
 498         kfree(buffer.pointer);
 499 }
 500 EXPORT_SYMBOL(acpi_handle_printk);
 501
 502 /**
 503  * acpi_has_method: Check whether @handle has a method named @name
 504  * @handle: ACPI device handle
 505  * @name: name of object or method
 506  *
 507  * Check whether @handle has a method named @name.
 508  */
 509 bool acpi_has_method(acpi_handle handle, char *name)
 510 {
 511         acpi_handle tmp;
 512
 513         return ACPI_SUCCESS(acpi_get_handle(handle, name, &tmp));
 514 }
 515 EXPORT_SYMBOL(acpi_has_method);
 516
 517 acpi_status acpi_execute_simple_method(acpi_handle handle, char *method,
 518                                        u64 arg)
 519 {
 520         union acpi_object obj = { .type = ACPI_TYPE_INTEGER };
 521         struct acpi_object_list arg_list = { .count = 1, .pointer = &obj, };
 522
 523         obj.integer.value = arg;
 524
 525         return acpi_evaluate_object(handle, method, &arg_list, NULL);
 526 }
 527 EXPORT_SYMBOL(acpi_execute_simple_method);
 528
 529 /**
 530  * acpi_evaluate_ej0: Evaluate _EJ0 method for hotplug operations
 531  * @handle: ACPI device handle
 532  *
 533  * Evaluate device's _EJ0 method for hotplug operations.
 534  */
 535 acpi_status acpi_evaluate_ej0(acpi_handle handle)
 536 {
 537         acpi_status status;
 538
 539         status = acpi_execute_simple_method(handle, "_EJ0", 1);
 540         if (status == AE_NOT_FOUND)
 541                 acpi_handle_warn(handle, "No _EJ0 support for device\n");
 542         else if (ACPI_FAILURE(status))
 543                 acpi_handle_warn(handle, "Eject failed (0x%x)\n", status);
 544
 545         return status;
 546 }
 547
 548 /**
 549  * acpi_evaluate_lck: Evaluate _LCK method to lock/unlock device
 550  * @handle: ACPI device handle
 551  * @lock: lock device if non-zero, otherwise unlock device
 552  *
 553  * Evaluate device's _LCK method if present to lock/unlock device
 554  */
 555 acpi_status acpi_evaluate_lck(acpi_handle handle, int lock)
 556 {
 557         acpi_status status;
 558
 559         status = acpi_execute_simple_method(handle, "_LCK", !!lock);
 560         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 561                 if (lock)
 562                         acpi_handle_warn(handle,
 563                                 "Locking device failed (0x%x)\n", status);
 564                 else
 565                         acpi_handle_warn(handle,
 566                                 "Unlocking device failed (0x%x)\n", status);
 567         }
 568
 569         return status;
 570 }
 571
 572 /**
 573  * acpi_evaluate_dsm - evaluate device's _DSM method
 574  * @handle: ACPI device handle
 575  * @uuid: UUID of requested functions, should be 16 bytes
 576  * @rev: revision number of requested function
 577  * @func: requested function number
 578  * @argv4: the function specific parameter
 579  *
 580  * Evaluate device's _DSM method with specified UUID, revision id and
 581  * function number. Caller needs to free the returned object.
 582  *
 583  * Though ACPI defines the fourth parameter for _DSM should be a package,
 584  * some old BIOSes do expect a buffer or an integer etc.
 585  */
 586 union acpi_object *
 587 acpi_evaluate_dsm(acpi_handle handle, const u8 *uuid, int rev, int func,
 588                   union acpi_object *argv4)
 589 {
 590         acpi_status ret;
 591         struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
 592         union acpi_object params[4];
 593         struct acpi_object_list input = {
 594                 .count = 4,
 595                 .pointer = params,
 596         };
 597
 598         params[0].type = ACPI_TYPE_BUFFER;
 599         params[0].buffer.length = 16;
 600         params[0].buffer.pointer = (char *)uuid;
 601         params[1].type = ACPI_TYPE_INTEGER;
 602         params[1].integer.value = rev;
 603         params[2].type = ACPI_TYPE_INTEGER;
 604         params[2].integer.value = func;
 605         if (argv4) {
 606                 params[3] = *argv4;
 607         } else {
 608                 params[3].type = ACPI_TYPE_PACKAGE;
 609                 params[3].package.count = 0;
 610                 params[3].package.elements = NULL;
 611         }
 612
 613         ret = acpi_evaluate_object(handle, "_DSM", &input, &buf);
 614         if (ACPI_SUCCESS(ret))
 615                 return (union acpi_object *)buf.pointer;
 616
 617         if (ret != AE_NOT_FOUND)
 618                 acpi_handle_warn(handle,
 619                                 "failed to evaluate _DSM (0x%x)\n", ret);
 620
 621         return NULL;
 622 }
 623 EXPORT_SYMBOL(acpi_evaluate_dsm);
 624
 625 /**
 626  * acpi_check_dsm - check if _DSM method supports requested functions.
 627  * @handle: ACPI device handle
 628  * @uuid: UUID of requested functions, should be 16 bytes at least
 629  * @rev: revision number of requested functions
 630  * @funcs: bitmap of requested functions
 631  * @exclude: excluding special value, used to support i915 and nouveau
 632  *
 633  * Evaluate device's _DSM method to check whether it supports requested
 634  * functions. Currently only support 64 functions at maximum, should be
 635  * enough for now.
 636  */
 637 bool acpi_check_dsm(acpi_handle handle, const u8 *uuid, int rev, u64 funcs)
 638 {
 639         int i;
 640         u64 mask = 0;
 641         union acpi_object *obj;
 642
 643         if (funcs == 0)
 644                 return false;
 645
 646         obj = acpi_evaluate_dsm(handle, uuid, rev, 0, NULL);
 647         if (!obj)
 648                 return false;
 649
 650         /* For compatibility, old BIOSes may return an integer */
 651         if (obj->type == ACPI_TYPE_INTEGER)
 652                 mask = obj->integer.value;
 653         else if (obj->type == ACPI_TYPE_BUFFER)
 654                 for (i = 0; i < obj->buffer.length && i < 8; i++)
 655                         mask |= (((u8)obj->buffer.pointer[i]) << (i * 8));
 656         ACPI_FREE(obj);
 657
 658         /*
 659          * Bit 0 indicates whether there's support for any functions other than
 660          * function 0 for the specified UUID and revision.
 661          */
 662         if ((mask & 0x1) && (mask & funcs) == funcs)
 663                 return true;
 664
 665         return false;
 666 }
 667 EXPORT_SYMBOL(acpi_check_dsm);