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 #include <acpi/acpi_bus.h>
  34 #include <acpi/acpi_drivers.h>
  35
  36 #include "internal.h"
  37
  38 #define _COMPONENT              ACPI_BUS_COMPONENT
  39 ACPI_MODULE_NAME("utils");
  40
  41 /* --------------------------------------------------------------------------
  42                             Object Evaluation Helpers
  43    -------------------------------------------------------------------------- */
  44 static void
  45 acpi_util_eval_error(acpi_handle h, acpi_string p, acpi_status s)
  46 {
  47 #ifdef ACPI_DEBUG_OUTPUT
  48         char prefix[80] = {'\0'};
  49         struct acpi_buffer buffer = {sizeof(prefix), prefix};
  50         acpi_get_name(h, ACPI_FULL_PATHNAME, &buffer);
  51         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluate [%s.%s]: %s\n",
  52                 (char *) prefix, p, acpi_format_exception(s)));
  53 #else
  54         return;
  55 #endif
  56 }
  57
  58 acpi_status
  59 acpi_extract_package(union acpi_object *package,
  60                      struct acpi_buffer *format, struct acpi_buffer *buffer)
  61 {
  62         u32 size_required = 0;
  63         u32 tail_offset = 0;
  64         char *format_string = NULL;
  65         u32 format_count = 0;
  66         u32 i = 0;
  67         u8 *head = NULL;
  68         u8 *tail = NULL;
  69
  70
  71         if (!package || (package->type != ACPI_TYPE_PACKAGE)
  72             || (package->package.count < 1)) {
  73                 printk(KERN_WARNING PREFIX "Invalid package argument\n");
  74                 return AE_BAD_PARAMETER;
  75         }
  76
  77         if (!format || !format->pointer || (format->length < 1)) {
  78                 printk(KERN_WARNING PREFIX "Invalid format argument\n");
  79                 return AE_BAD_PARAMETER;
  80         }
  81
  82         if (!buffer) {
  83                 printk(KERN_WARNING PREFIX "Invalid buffer argument\n");
  84                 return AE_BAD_PARAMETER;
  85         }
  86
  87         format_count = (format->length / sizeof(char)) - 1;
  88         if (format_count > package->package.count) {
  89                 printk(KERN_WARNING PREFIX "Format specifies more objects [%d]"
  90                               " than exist in package [%d].\n",
  91                               format_count, package->package.count);
  92                 return AE_BAD_DATA;
  93         }
  94
  95         format_string = format->pointer;
  96
  97         /*
  98          * Calculate size_required.
  99          */
 100         for (i = 0; i < format_count; i++) {
 101
 102                 union acpi_object *element = &(package->package.elements[i]);
 103
 104                 if (!element) {
 105                         return AE_BAD_DATA;
 106                 }
 107
 108                 switch (element->type) {
 109
 110                 case ACPI_TYPE_INTEGER:
 111                         switch (format_string[i]) {
 112                         case 'N':
 113                                 size_required += sizeof(u64);
 114                                 tail_offset += sizeof(u64);
 115                                 break;
 116                         case 'S':
 117                                 size_required +=
 118                                     sizeof(char *) + sizeof(u64) +
 119                                     sizeof(char);
 120                                 tail_offset += sizeof(char *);
 121                                 break;
 122                         default:
 123                                 printk(KERN_WARNING PREFIX "Invalid package element"
 124                                               " [%d]: got number, expecing"
 125                                               " [%c]\n",
 126                                               i, format_string[i]);
 127                                 return AE_BAD_DATA;
 128                                 break;
 129                         }
 130                         break;
 131
 132                 case ACPI_TYPE_STRING:
 133                 case ACPI_TYPE_BUFFER:
 134                         switch (format_string[i]) {
 135                         case 'S':
 136                                 size_required +=
 137                                     sizeof(char *) +
 138                                     (element->string.length * sizeof(char)) +
 139                                     sizeof(char);
 140                                 tail_offset += sizeof(char *);
 141                                 break;
 142                         case 'B':
 143                                 size_required +=
 144                                     sizeof(u8 *) +
 145                                     (element->buffer.length * sizeof(u8));
 146                                 tail_offset += sizeof(u8 *);
 147                                 break;
 148                         default:
 149                                 printk(KERN_WARNING PREFIX "Invalid package element"
 150                                               " [%d] got string/buffer,"
 151                                               " expecing [%c]\n",
 152                                               i, format_string[i]);
 153                                 return AE_BAD_DATA;
 154                                 break;
 155                         }
 156                         break;
 157
 158                 case ACPI_TYPE_PACKAGE:
 159                 default:
 160                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 161                                           "Found unsupported element at index=%d\n",
 162                                           i));
 163                         /* TBD: handle nested packages... */
 164                         return AE_SUPPORT;
 165                         break;
 166                 }
 167         }
 168
 169         /*
 170          * Validate output buffer.
 171          */
 172         if (buffer->length < size_required) {
 173                 buffer->length = size_required;
 174                 return AE_BUFFER_OVERFLOW;
 175         } else if (buffer->length != size_required || !buffer->pointer) {
 176                 return AE_BAD_PARAMETER;
 177         }
 178
 179         head = buffer->pointer;
 180         tail = buffer->pointer + tail_offset;
 181
 182         /*
 183          * Extract package data.
 184          */
 185         for (i = 0; i < format_count; i++) {
 186
 187                 u8 **pointer = NULL;
 188                 union acpi_object *element = &(package->package.elements[i]);
 189
 190                 if (!element) {
 191                         return AE_BAD_DATA;
 192                 }
 193
 194                 switch (element->type) {
 195
 196                 case ACPI_TYPE_INTEGER:
 197                         switch (format_string[i]) {
 198                         case 'N':
 199                                 *((u64 *) head) =
 200                                     element->integer.value;
 201                                 head += sizeof(u64);
 202                                 break;
 203                         case 'S':
 204                                 pointer = (u8 **) head;
 205                                 *pointer = tail;
 206                                 *((u64 *) tail) =
 207                                     element->integer.value;
 208                                 head += sizeof(u64 *);
 209                                 tail += sizeof(u64);
 210                                 /* NULL terminate string */
 211                                 *tail = (char)0;
 212                                 tail += sizeof(char);
 213                                 break;
 214                         default:
 215                                 /* Should never get here */
 216                                 break;
 217                         }
 218                         break;
 219
 220                 case ACPI_TYPE_STRING:
 221                 case ACPI_TYPE_BUFFER:
 222                         switch (format_string[i]) {
 223                         case 'S':
 224                                 pointer = (u8 **) head;
 225                                 *pointer = tail;
 226                                 memcpy(tail, element->string.pointer,
 227                                        element->string.length);
 228                                 head += sizeof(char *);
 229                                 tail += element->string.length * sizeof(char);
 230                                 /* NULL terminate string */
 231                                 *tail = (char)0;
 232                                 tail += sizeof(char);
 233                                 break;
 234                         case 'B':
 235                                 pointer = (u8 **) head;
 236                                 *pointer = tail;
 237                                 memcpy(tail, element->buffer.pointer,
 238                                        element->buffer.length);
 239                                 head += sizeof(u8 *);
 240                                 tail += element->buffer.length * sizeof(u8);
 241                                 break;
 242                         default:
 243                                 /* Should never get here */
 244                                 break;
 245                         }
 246                         break;
 247
 248                 case ACPI_TYPE_PACKAGE:
 249                         /* TBD: handle nested packages... */
 250                 default:
 251                         /* Should never get here */
 252                         break;
 253                 }
 254         }
 255
 256         return AE_OK;
 257 }
 258
 259 EXPORT_SYMBOL(acpi_extract_package);
 260
 261 acpi_status
 262 acpi_evaluate_integer(acpi_handle handle,
 263                       acpi_string pathname,
 264                       struct acpi_object_list *arguments, unsigned long long *data)
 265 {
 266         acpi_status status = AE_OK;
 267         union acpi_object element;
 268         struct acpi_buffer buffer = { 0, NULL };
 269
 270         if (!data)
 271                 return AE_BAD_PARAMETER;
 272
 273         buffer.length = sizeof(union acpi_object);
 274         buffer.pointer = &element;
 275         status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
 276         if (ACPI_FAILURE(status)) {
 277                 acpi_util_eval_error(handle, pathname, status);
 278                 return status;
 279         }
 280
 281         if (element.type != ACPI_TYPE_INTEGER) {
 282                 acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
 283                 return AE_BAD_DATA;
 284         }
 285
 286         *data = element.integer.value;
 287
 288         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data));
 289
 290         return AE_OK;
 291 }
 292
 293 EXPORT_SYMBOL(acpi_evaluate_integer);
 294
 295 acpi_status
 296 acpi_evaluate_reference(acpi_handle handle,
 297                         acpi_string pathname,
 298                         struct acpi_object_list *arguments,
 299                         struct acpi_handle_list *list)
 300 {
 301         acpi_status status = AE_OK;
 302         union acpi_object *package = NULL;
 303         union acpi_object *element = NULL;
 304         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 305         u32 i = 0;
 306
 307
 308         if (!list) {
 309                 return AE_BAD_PARAMETER;
 310         }
 311
 312         /* Evaluate object. */
 313
 314         status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
 315         if (ACPI_FAILURE(status))
 316                 goto end;
 317
 318         package = buffer.pointer;
 319
 320         if ((buffer.length == 0) || !package) {
 321                 printk(KERN_ERR PREFIX "No return object (len %X ptr %p)\n",
 322                             (unsigned)buffer.length, package);
 323                 status = AE_BAD_DATA;
 324                 acpi_util_eval_error(handle, pathname, status);
 325                 goto end;
 326         }
 327         if (package->type != ACPI_TYPE_PACKAGE) {
 328                 printk(KERN_ERR PREFIX "Expecting a [Package], found type %X\n",
 329                             package->type);
 330                 status = AE_BAD_DATA;
 331                 acpi_util_eval_error(handle, pathname, status);
 332                 goto end;
 333         }
 334         if (!package->package.count) {
 335                 printk(KERN_ERR PREFIX "[Package] has zero elements (%p)\n",
 336                             package);
 337                 status = AE_BAD_DATA;
 338                 acpi_util_eval_error(handle, pathname, status);
 339                 goto end;
 340         }
 341
 342         if (package->package.count > ACPI_MAX_HANDLES) {
 343                 return AE_NO_MEMORY;
 344         }
 345         list->count = package->package.count;
 346
 347         /* Extract package data. */
 348
 349         for (i = 0; i < list->count; i++) {
 350
 351                 element = &(package->package.elements[i]);
 352
 353                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
 354                         status = AE_BAD_DATA;
 355                         printk(KERN_ERR PREFIX
 356                                     "Expecting a [Reference] package element, found type %X\n",
 357                                     element->type);
 358                         acpi_util_eval_error(handle, pathname, status);
 359                         break;
 360                 }
 361
 362                 if (!element->reference.handle) {
 363                         printk(KERN_WARNING PREFIX "Invalid reference in"
 364                                " package %s\n", pathname);
 365                         status = AE_NULL_ENTRY;
 366                         break;
 367                 }
 368                 /* Get the  acpi_handle. */
 369
 370                 list->handles[i] = element->reference.handle;
 371                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
 372                                   list->handles[i]));
 373         }
 374
 375       end:
 376         if (ACPI_FAILURE(status)) {
 377                 list->count = 0;
 378                 //kfree(list->handles);
 379         }
 380
 381         kfree(buffer.pointer);
 382
 383         return status;
 384 }
 385
 386 EXPORT_SYMBOL(acpi_evaluate_reference);
 387
 388 acpi_status
 389 acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld)
 390 {
 391         acpi_status status;
 392         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 393         union acpi_object *output;
 394
 395         status = acpi_evaluate_object(handle, "_PLD", NULL, &buffer);
 396
 397         if (ACPI_FAILURE(status))
 398                 return status;
 399
 400         output = buffer.pointer;
 401
 402         if (!output || output->type != ACPI_TYPE_PACKAGE
 403             || !output->package.count
 404             || output->package.elements[0].type != ACPI_TYPE_BUFFER
 405             || output->package.elements[0].buffer.length < ACPI_PLD_REV1_BUFFER_SIZE) {
 406                 status = AE_TYPE;
 407                 goto out;
 408         }
 409
 410         status = acpi_decode_pld_buffer(
 411                         output->package.elements[0].buffer.pointer,
 412                         output->package.elements[0].buffer.length,
 413                         pld);
 414
 415 out:
 416         kfree(buffer.pointer);
 417         return status;
 418 }
 419 EXPORT_SYMBOL(acpi_get_physical_device_location);
 420
 421 /**
 422  * acpi_evaluate_hotplug_ost: Evaluate _OST for hotplug operations
 423  * @handle: ACPI device handle
 424  * @source_event: source event code
 425  * @status_code: status code
 426  * @status_buf: optional detailed information (NULL if none)
 427  *
 428  * Evaluate _OST for hotplug operations. All ACPI hotplug handlers
 429  * must call this function when evaluating _OST for hotplug operations.
 430  * When the platform does not support _OST, this function has no effect.
 431  */
 432 acpi_status
 433 acpi_evaluate_hotplug_ost(acpi_handle handle, u32 source_event,
 434                 u32 status_code, struct acpi_buffer *status_buf)
 435 {
 436 #ifdef ACPI_HOTPLUG_OST
 437         union acpi_object params[3] = {
 438                 {.type = ACPI_TYPE_INTEGER,},
 439                 {.type = ACPI_TYPE_INTEGER,},
 440                 {.type = ACPI_TYPE_BUFFER,}
 441         };
 442         struct acpi_object_list arg_list = {3, params};
 443         acpi_status status;
 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         status = acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
 456         return status;
 457 #else
 458         return AE_OK;
 459 #endif
 460 }
 461 EXPORT_SYMBOL(acpi_evaluate_hotplug_ost);
 462
 463 /**
 464  * acpi_handle_printk: Print message with ACPI prefix and object path
 465  *
 466  * This function is called through acpi_handle_<level> macros and prints
 467  * a message with ACPI prefix and object path.  This function acquires
 468  * the global namespace mutex to obtain an object path.  In interrupt
 469  * context, it shows the object path as <n/a>.
 470  */
 471 void
 472 acpi_handle_printk(const char *level, acpi_handle handle, const char *fmt, ...)
 473 {
 474         struct va_format vaf;
 475         va_list args;
 476         struct acpi_buffer buffer = {
 477                 .length = ACPI_ALLOCATE_BUFFER,
 478                 .pointer = NULL
 479         };
 480         const char *path;
 481
 482         va_start(args, fmt);
 483         vaf.fmt = fmt;
 484         vaf.va = &args;
 485
 486         if (in_interrupt() ||
 487             acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer) != AE_OK)
 488                 path = "<n/a>";
 489         else
 490                 path = buffer.pointer;
 491
 492         printk("%sACPI: %s: %pV", level, path, &vaf);
 493
 494         va_end(args);
 495         kfree(buffer.pointer);
 496 }
 497 EXPORT_SYMBOL(acpi_handle_printk);
 498
 499 /**
 500  * acpi_has_method: Check whether @handle has a method named @name
 501  * @handle: ACPI device handle
 502  * @name: name of object or method
 503  *
 504  * Check whether @handle has a method named @name.
 505  */
 506 bool acpi_has_method(acpi_handle handle, char *name)
 507 {
 508         acpi_handle tmp;
 509
 510         return ACPI_SUCCESS(acpi_get_handle(handle, name, &tmp));
 511 }
 512 EXPORT_SYMBOL(acpi_has_method);
 513
 514 acpi_status acpi_execute_simple_method(acpi_handle handle, char *method,
 515                                        u64 arg)
 516 {
 517         union acpi_object obj = { .type = ACPI_TYPE_INTEGER };
 518         struct acpi_object_list arg_list = { .count = 1, .pointer = &obj, };
 519
 520         obj.integer.value = arg;
 521
 522         return acpi_evaluate_object(handle, method, &arg_list, NULL);
 523 }
 524 EXPORT_SYMBOL(acpi_execute_simple_method);
 525
 526 /**
 527  * acpi_evaluate_ej0: Evaluate _EJ0 method for hotplug operations
 528  * @handle: ACPI device handle
 529  *
 530  * Evaluate device's _EJ0 method for hotplug operations.
 531  */
 532 acpi_status acpi_evaluate_ej0(acpi_handle handle)
 533 {
 534         acpi_status status;
 535
 536         status = acpi_execute_simple_method(handle, "_EJ0", 1);
 537         if (status == AE_NOT_FOUND)
 538                 acpi_handle_warn(handle, "No _EJ0 support for device\n");
 539         else if (ACPI_FAILURE(status))
 540                 acpi_handle_warn(handle, "Eject failed (0x%x)\n", status);
 541
 542         return status;
 543 }
 544
 545 /**
 546  * acpi_evaluate_lck: Evaluate _LCK method to lock/unlock device
 547  * @handle: ACPI device handle
 548  * @lock: lock device if non-zero, otherwise unlock device
 549  *
 550  * Evaluate device's _LCK method if present to lock/unlock device
 551  */
 552 acpi_status acpi_evaluate_lck(acpi_handle handle, int lock)
 553 {
 554         acpi_status status;
 555
 556         status = acpi_execute_simple_method(handle, "_LCK", !!lock);
 557         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 558                 if (lock)
 559                         acpi_handle_warn(handle,
 560                                 "Locking device failed (0x%x)\n", status);
 561                 else
 562                         acpi_handle_warn(handle,
 563                                 "Unlocking device failed (0x%x)\n", status);
 564         }
 565
 566         return status;
 567 }