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, expecting"
 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                                               " expecting [%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 == ACPI_ALLOCATE_BUFFER) {
 173                 buffer->pointer = ACPI_ALLOCATE(size_required);
 174                 if (!buffer->pointer)
 175                         return AE_NO_MEMORY;
 176                 buffer->length = size_required;
 177                 memset(buffer->pointer, 0, size_required);
 178         } else {
 179                 if (buffer->length < size_required) {
 180                         buffer->length = size_required;
 181                         return AE_BUFFER_OVERFLOW;
 182                 } else if (buffer->length != size_required ||
 183                            !buffer->pointer) {
 184                         return AE_BAD_PARAMETER;
 185                 }
 186         }
 187
 188         head = buffer->pointer;
 189         tail = buffer->pointer + tail_offset;
 190
 191         /*
 192          * Extract package data.
 193          */
 194         for (i = 0; i < format_count; i++) {
 195
 196                 u8 **pointer = NULL;
 197                 union acpi_object *element = &(package->package.elements[i]);
 198
 199                 if (!element) {
 200                         return AE_BAD_DATA;
 201                 }
 202
 203                 switch (element->type) {
 204
 205                 case ACPI_TYPE_INTEGER:
 206                         switch (format_string[i]) {
 207                         case 'N':
 208                                 *((u64 *) head) =
 209                                     element->integer.value;
 210                                 head += sizeof(u64);
 211                                 break;
 212                         case 'S':
 213                                 pointer = (u8 **) head;
 214                                 *pointer = tail;
 215                                 *((u64 *) tail) =
 216                                     element->integer.value;
 217                                 head += sizeof(u64 *);
 218                                 tail += sizeof(u64);
 219                                 /* NULL terminate string */
 220                                 *tail = (char)0;
 221                                 tail += sizeof(char);
 222                                 break;
 223                         default:
 224                                 /* Should never get here */
 225                                 break;
 226                         }
 227                         break;
 228
 229                 case ACPI_TYPE_STRING:
 230                 case ACPI_TYPE_BUFFER:
 231                         switch (format_string[i]) {
 232                         case 'S':
 233                                 pointer = (u8 **) head;
 234                                 *pointer = tail;
 235                                 memcpy(tail, element->string.pointer,
 236                                        element->string.length);
 237                                 head += sizeof(char *);
 238                                 tail += element->string.length * sizeof(char);
 239                                 /* NULL terminate string */
 240                                 *tail = (char)0;
 241                                 tail += sizeof(char);
 242                                 break;
 243                         case 'B':
 244                                 pointer = (u8 **) head;
 245                                 *pointer = tail;
 246                                 memcpy(tail, element->buffer.pointer,
 247                                        element->buffer.length);
 248                                 head += sizeof(u8 *);
 249                                 tail += element->buffer.length * sizeof(u8);
 250                                 break;
 251                         default:
 252                                 /* Should never get here */
 253                                 break;
 254                         }
 255                         break;
 256
 257                 case ACPI_TYPE_PACKAGE:
 258                         /* TBD: handle nested packages... */
 259                 default:
 260                         /* Should never get here */
 261                         break;
 262                 }
 263         }
 264
 265         return AE_OK;
 266 }
 267
 268 EXPORT_SYMBOL(acpi_extract_package);
 269
 270 acpi_status
 271 acpi_evaluate_integer(acpi_handle handle,
 272                       acpi_string pathname,
 273                       struct acpi_object_list *arguments, unsigned long long *data)
 274 {
 275         acpi_status status = AE_OK;
 276         union acpi_object element;
 277         struct acpi_buffer buffer = { 0, NULL };
 278
 279         if (!data)
 280                 return AE_BAD_PARAMETER;
 281
 282         buffer.length = sizeof(union acpi_object);
 283         buffer.pointer = &element;
 284         status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
 285         if (ACPI_FAILURE(status)) {
 286                 acpi_util_eval_error(handle, pathname, status);
 287                 return status;
 288         }
 289
 290         if (element.type != ACPI_TYPE_INTEGER) {
 291                 acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
 292                 return AE_BAD_DATA;
 293         }
 294
 295         *data = element.integer.value;
 296
 297         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data));
 298
 299         return AE_OK;
 300 }
 301
 302 EXPORT_SYMBOL(acpi_evaluate_integer);
 303
 304 acpi_status
 305 acpi_evaluate_reference(acpi_handle handle,
 306                         acpi_string pathname,
 307                         struct acpi_object_list *arguments,
 308                         struct acpi_handle_list *list)
 309 {
 310         acpi_status status = AE_OK;
 311         union acpi_object *package = NULL;
 312         union acpi_object *element = NULL;
 313         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 314         u32 i = 0;
 315
 316
 317         if (!list) {
 318                 return AE_BAD_PARAMETER;
 319         }
 320
 321         /* Evaluate object. */
 322
 323         status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
 324         if (ACPI_FAILURE(status))
 325                 goto end;
 326
 327         package = buffer.pointer;
 328
 329         if ((buffer.length == 0) || !package) {
 330                 printk(KERN_ERR PREFIX "No return object (len %X ptr %p)\n",
 331                             (unsigned)buffer.length, package);
 332                 status = AE_BAD_DATA;
 333                 acpi_util_eval_error(handle, pathname, status);
 334                 goto end;
 335         }
 336         if (package->type != ACPI_TYPE_PACKAGE) {
 337                 printk(KERN_ERR PREFIX "Expecting a [Package], found type %X\n",
 338                             package->type);
 339                 status = AE_BAD_DATA;
 340                 acpi_util_eval_error(handle, pathname, status);
 341                 goto end;
 342         }
 343         if (!package->package.count) {
 344                 printk(KERN_ERR PREFIX "[Package] has zero elements (%p)\n",
 345                             package);
 346                 status = AE_BAD_DATA;
 347                 acpi_util_eval_error(handle, pathname, status);
 348                 goto end;
 349         }
 350
 351         if (package->package.count > ACPI_MAX_HANDLES) {
 352                 return AE_NO_MEMORY;
 353         }
 354         list->count = package->package.count;
 355
 356         /* Extract package data. */
 357
 358         for (i = 0; i < list->count; i++) {
 359
 360                 element = &(package->package.elements[i]);
 361
 362                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
 363                         status = AE_BAD_DATA;
 364                         printk(KERN_ERR PREFIX
 365                                     "Expecting a [Reference] package element, found type %X\n",
 366                                     element->type);
 367                         acpi_util_eval_error(handle, pathname, status);
 368                         break;
 369                 }
 370
 371                 if (!element->reference.handle) {
 372                         printk(KERN_WARNING PREFIX "Invalid reference in"
 373                                " package %s\n", pathname);
 374                         status = AE_NULL_ENTRY;
 375                         break;
 376                 }
 377                 /* Get the  acpi_handle. */
 378
 379                 list->handles[i] = element->reference.handle;
 380                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
 381                                   list->handles[i]));
 382         }
 383
 384       end:
 385         if (ACPI_FAILURE(status)) {
 386                 list->count = 0;
 387                 //kfree(list->handles);
 388         }
 389
 390         kfree(buffer.pointer);
 391
 392         return status;
 393 }
 394
 395 EXPORT_SYMBOL(acpi_evaluate_reference);
 396
 397 acpi_status
 398 acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld)
 399 {
 400         acpi_status status;
 401         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 402         union acpi_object *output;
 403
 404         status = acpi_evaluate_object(handle, "_PLD", NULL, &buffer);
 405
 406         if (ACPI_FAILURE(status))
 407                 return status;
 408
 409         output = buffer.pointer;
 410
 411         if (!output || output->type != ACPI_TYPE_PACKAGE
 412             || !output->package.count
 413             || output->package.elements[0].type != ACPI_TYPE_BUFFER
 414             || output->package.elements[0].buffer.length < ACPI_PLD_REV1_BUFFER_SIZE) {
 415                 status = AE_TYPE;
 416                 goto out;
 417         }
 418
 419         status = acpi_decode_pld_buffer(
 420                         output->package.elements[0].buffer.pointer,
 421                         output->package.elements[0].buffer.length,
 422                         pld);
 423
 424 out:
 425         kfree(buffer.pointer);
 426         return status;
 427 }
 428 EXPORT_SYMBOL(acpi_get_physical_device_location);
 429
 430 /**
 431  * acpi_evaluate_hotplug_ost: Evaluate _OST for hotplug operations
 432  * @handle: ACPI device handle
 433  * @source_event: source event code
 434  * @status_code: status code
 435  * @status_buf: optional detailed information (NULL if none)
 436  *
 437  * Evaluate _OST for hotplug operations. All ACPI hotplug handlers
 438  * must call this function when evaluating _OST for hotplug operations.
 439  * When the platform does not support _OST, this function has no effect.
 440  */
 441 acpi_status
 442 acpi_evaluate_hotplug_ost(acpi_handle handle, u32 source_event,
 443                 u32 status_code, struct acpi_buffer *status_buf)
 444 {
 445 #ifdef ACPI_HOTPLUG_OST
 446         union acpi_object params[3] = {
 447                 {.type = ACPI_TYPE_INTEGER,},
 448                 {.type = ACPI_TYPE_INTEGER,},
 449                 {.type = ACPI_TYPE_BUFFER,}
 450         };
 451         struct acpi_object_list arg_list = {3, params};
 452         acpi_status status;
 453
 454         params[0].integer.value = source_event;
 455         params[1].integer.value = status_code;
 456         if (status_buf != NULL) {
 457                 params[2].buffer.pointer = status_buf->pointer;
 458                 params[2].buffer.length = status_buf->length;
 459         } else {
 460                 params[2].buffer.pointer = NULL;
 461                 params[2].buffer.length = 0;
 462         }
 463
 464         status = acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
 465         return status;
 466 #else
 467         return AE_OK;
 468 #endif
 469 }
 470 EXPORT_SYMBOL(acpi_evaluate_hotplug_ost);
 471
 472 /**
 473  * acpi_handle_printk: Print message with ACPI prefix and object path
 474  *
 475  * This function is called through acpi_handle_<level> macros and prints
 476  * a message with ACPI prefix and object path.  This function acquires
 477  * the global namespace mutex to obtain an object path.  In interrupt
 478  * context, it shows the object path as <n/a>.
 479  */
 480 void
 481 acpi_handle_printk(const char *level, acpi_handle handle, const char *fmt, ...)
 482 {
 483         struct va_format vaf;
 484         va_list args;
 485         struct acpi_buffer buffer = {
 486                 .length = ACPI_ALLOCATE_BUFFER,
 487                 .pointer = NULL
 488         };
 489         const char *path;
 490
 491         va_start(args, fmt);
 492         vaf.fmt = fmt;
 493         vaf.va = &args;
 494
 495         if (in_interrupt() ||
 496             acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer) != AE_OK)
 497                 path = "<n/a>";
 498         else
 499                 path = buffer.pointer;
 500
 501         printk("%sACPI: %s: %pV", level, path, &vaf);
 502
 503         va_end(args);
 504         kfree(buffer.pointer);
 505 }
 506 EXPORT_SYMBOL(acpi_handle_printk);
 507
 508 /**
 509  * acpi_has_method: Check whether @handle has a method named @name
 510  * @handle: ACPI device handle
 511  * @name: name of object or method
 512  *
 513  * Check whether @handle has a method named @name.
 514  */
 515 bool acpi_has_method(acpi_handle handle, char *name)
 516 {
 517         acpi_handle tmp;
 518
 519         return ACPI_SUCCESS(acpi_get_handle(handle, name, &tmp));
 520 }
 521 EXPORT_SYMBOL(acpi_has_method);
 522
 523 acpi_status acpi_execute_simple_method(acpi_handle handle, char *method,
 524                                        u64 arg)
 525 {
 526         union acpi_object obj = { .type = ACPI_TYPE_INTEGER };
 527         struct acpi_object_list arg_list = { .count = 1, .pointer = &obj, };
 528
 529         obj.integer.value = arg;
 530
 531         return acpi_evaluate_object(handle, method, &arg_list, NULL);
 532 }
 533 EXPORT_SYMBOL(acpi_execute_simple_method);
 534
 535 /**
 536  * acpi_evaluate_ej0: Evaluate _EJ0 method for hotplug operations
 537  * @handle: ACPI device handle
 538  *
 539  * Evaluate device's _EJ0 method for hotplug operations.
 540  */
 541 acpi_status acpi_evaluate_ej0(acpi_handle handle)
 542 {
 543         acpi_status status;
 544
 545         status = acpi_execute_simple_method(handle, "_EJ0", 1);
 546         if (status == AE_NOT_FOUND)
 547                 acpi_handle_warn(handle, "No _EJ0 support for device\n");
 548         else if (ACPI_FAILURE(status))
 549                 acpi_handle_warn(handle, "Eject failed (0x%x)\n", status);
 550
 551         return status;
 552 }
 553
 554 /**
 555  * acpi_evaluate_lck: Evaluate _LCK method to lock/unlock device
 556  * @handle: ACPI device handle
 557  * @lock: lock device if non-zero, otherwise unlock device
 558  *
 559  * Evaluate device's _LCK method if present to lock/unlock device
 560  */
 561 acpi_status acpi_evaluate_lck(acpi_handle handle, int lock)
 562 {
 563         acpi_status status;
 564
 565         status = acpi_execute_simple_method(handle, "_LCK", !!lock);
 566         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 567                 if (lock)
 568                         acpi_handle_warn(handle,
 569                                 "Locking device failed (0x%x)\n", status);
 570                 else
 571                         acpi_handle_warn(handle,
 572                                 "Unlocking device failed (0x%x)\n", status);
 573         }
 574
 575         return status;
 576 }