drivers/acpi/acpica/hwsleep.c

   1
   2 /******************************************************************************
   3  *
   4  * Name: hwsleep.c - ACPI Hardware Sleep/Wake Interface
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2008, Intel Corp.
  10  * All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions, and the following disclaimer,
  17  *    without modification.
  18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  19  *    substantially similar to the "NO WARRANTY" disclaimer below
  20  *    ("Disclaimer") and any redistribution must be conditioned upon
  21  *    including a substantially similar Disclaimer requirement for further
  22  *    binary redistribution.
  23  * 3. Neither the names of the above-listed copyright holders nor the names
  24  *    of any contributors may be used to endorse or promote products derived
  25  *    from this software without specific prior written permission.
  26  *
  27  * Alternatively, this software may be distributed under the terms of the
  28  * GNU General Public License ("GPL") version 2 as published by the Free
  29  * Software Foundation.
  30  *
  31  * NO WARRANTY
  32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  42  * POSSIBILITY OF SUCH DAMAGES.
  43  */
  44
  45 #include <acpi/acpi.h>
  46 #include "accommon.h"
  47 #include "actables.h"
  48
  49 #define _COMPONENT          ACPI_HARDWARE
  50 ACPI_MODULE_NAME("hwsleep")
  51
  52 /*******************************************************************************
  53  *
  54  * FUNCTION:    acpi_set_firmware_waking_vector
  55  *
  56  * PARAMETERS:  physical_address    - 32-bit physical address of ACPI real mode
  57  *                                    entry point.
  58  *
  59  * RETURN:      Status
  60  *
  61  * DESCRIPTION: Sets the 32-bit firmware_waking_vector field of the FACS
  62  *
  63  ******************************************************************************/
  64 acpi_status
  65 acpi_set_firmware_waking_vector(u32 physical_address)
  66 {
  67         ACPI_FUNCTION_TRACE(acpi_set_firmware_waking_vector);
  68
  69
  70         /*
  71          * According to the ACPI specification 2.0c and later, the 64-bit
  72          * waking vector should be cleared and the 32-bit waking vector should
  73          * be used, unless we want the wake-up code to be called by the BIOS in
  74          * Protected Mode.  Some systems (for example HP dv5-1004nr) are known
  75          * to fail to resume if the 64-bit vector is used.
  76          */
  77
  78         /* Set the 32-bit vector */
  79
  80         acpi_gbl_FACS->firmware_waking_vector = physical_address;
  81
  82         /* Clear the 64-bit vector if it exists */
  83
  84         if ((acpi_gbl_FACS->length > 32) && (acpi_gbl_FACS->version >= 1)) {
  85                 acpi_gbl_FACS->xfirmware_waking_vector = 0;
  86         }
  87
  88         return_ACPI_STATUS(AE_OK);
  89 }
  90
  91 ACPI_EXPORT_SYMBOL(acpi_set_firmware_waking_vector)
  92
  93 #if ACPI_MACHINE_WIDTH == 64
  94 /*******************************************************************************
  95  *
  96  * FUNCTION:    acpi_set_firmware_waking_vector64
  97  *
  98  * PARAMETERS:  physical_address    - 64-bit physical address of ACPI protected
  99  *                                    mode entry point.
 100  *
 101  * RETURN:      Status
 102  *
 103  * DESCRIPTION: Sets the 64-bit X_firmware_waking_vector field of the FACS, if
 104  *              it exists in the table. This function is intended for use with
 105  *              64-bit host operating systems.
 106  *
 107  ******************************************************************************/
 108 acpi_status
 109 acpi_set_firmware_waking_vector64(u64 physical_address)
 110 {
 111         ACPI_FUNCTION_TRACE(acpi_set_firmware_waking_vector64);
 112
 113
 114         /* Determine if the 64-bit vector actually exists */
 115
 116         if ((acpi_gbl_FACS->length <= 32) || (acpi_gbl_FACS->version < 1)) {
 117                 return_ACPI_STATUS(AE_NOT_EXIST);
 118         }
 119
 120         /* Clear 32-bit vector, set the 64-bit X_ vector */
 121
 122         acpi_gbl_FACS->firmware_waking_vector = 0;
 123         acpi_gbl_FACS->xfirmware_waking_vector = physical_address;
 124
 125         return_ACPI_STATUS(AE_OK);
 126 }
 127
 128 ACPI_EXPORT_SYMBOL(acpi_set_firmware_waking_vector64)
 129 #endif
 130
 131 /*******************************************************************************
 132  *
 133  * FUNCTION:    acpi_enter_sleep_state_prep
 134  *
 135  * PARAMETERS:  sleep_state         - Which sleep state to enter
 136  *
 137  * RETURN:      Status
 138  *
 139  * DESCRIPTION: Prepare to enter a system sleep state (see ACPI 2.0 spec p 231)
 140  *              This function must execute with interrupts enabled.
 141  *              We break sleeping into 2 stages so that OSPM can handle
 142  *              various OS-specific tasks between the two steps.
 143  *
 144  ******************************************************************************/
 145 acpi_status acpi_enter_sleep_state_prep(u8 sleep_state)
 146 {
 147         acpi_status status;
 148         struct acpi_object_list arg_list;
 149         union acpi_object arg;
 150
 151         ACPI_FUNCTION_TRACE(acpi_enter_sleep_state_prep);
 152
 153         /* _PSW methods could be run here to enable wake-on keyboard, LAN, etc. */
 154
 155         status = acpi_get_sleep_type_data(sleep_state,
 156                                           &acpi_gbl_sleep_type_a,
 157                                           &acpi_gbl_sleep_type_b);
 158         if (ACPI_FAILURE(status)) {
 159                 return_ACPI_STATUS(status);
 160         }
 161
 162         /* Setup parameter object */
 163
 164         arg_list.count = 1;
 165         arg_list.pointer = &arg;
 166
 167         arg.type = ACPI_TYPE_INTEGER;
 168         arg.integer.value = sleep_state;
 169
 170         /* Run the _PTS method */
 171
 172         status = acpi_evaluate_object(NULL, METHOD_NAME__PTS, &arg_list, NULL);
 173         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 174                 return_ACPI_STATUS(status);
 175         }
 176
 177         /* Setup the argument to _SST */
 178
 179         switch (sleep_state) {
 180         case ACPI_STATE_S0:
 181                 arg.integer.value = ACPI_SST_WORKING;
 182                 break;
 183
 184         case ACPI_STATE_S1:
 185         case ACPI_STATE_S2:
 186         case ACPI_STATE_S3:
 187                 arg.integer.value = ACPI_SST_SLEEPING;
 188                 break;
 189
 190         case ACPI_STATE_S4:
 191                 arg.integer.value = ACPI_SST_SLEEP_CONTEXT;
 192                 break;
 193
 194         default:
 195                 arg.integer.value = ACPI_SST_INDICATOR_OFF;     /* Default is off */
 196                 break;
 197         }
 198
 199         /*
 200          * Set the system indicators to show the desired sleep state.
 201          * _SST is an optional method (return no error if not found)
 202          */
 203         status = acpi_evaluate_object(NULL, METHOD_NAME__SST, &arg_list, NULL);
 204         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 205                 ACPI_EXCEPTION((AE_INFO, status,
 206                                 "While executing method _SST"));
 207         }
 208
 209         return_ACPI_STATUS(AE_OK);
 210 }
 211
 212 ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state_prep)
 213
 214 /*******************************************************************************
 215  *
 216  * FUNCTION:    acpi_enter_sleep_state
 217  *
 218  * PARAMETERS:  sleep_state         - Which sleep state to enter
 219  *
 220  * RETURN:      Status
 221  *
 222  * DESCRIPTION: Enter a system sleep state (see ACPI 2.0 spec p 231)
 223  *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
 224  *
 225  ******************************************************************************/
 226 acpi_status asmlinkage acpi_enter_sleep_state(u8 sleep_state)
 227 {
 228         u32 pm1a_control;
 229         u32 pm1b_control;
 230         struct acpi_bit_register_info *sleep_type_reg_info;
 231         struct acpi_bit_register_info *sleep_enable_reg_info;
 232         u32 in_value;
 233         struct acpi_object_list arg_list;
 234         union acpi_object arg;
 235         acpi_status status;
 236
 237         ACPI_FUNCTION_TRACE(acpi_enter_sleep_state);
 238
 239         if ((acpi_gbl_sleep_type_a > ACPI_SLEEP_TYPE_MAX) ||
 240             (acpi_gbl_sleep_type_b > ACPI_SLEEP_TYPE_MAX)) {
 241                 ACPI_ERROR((AE_INFO, "Sleep values out of range: A=%X B=%X",
 242                             acpi_gbl_sleep_type_a, acpi_gbl_sleep_type_b));
 243                 return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
 244         }
 245
 246         sleep_type_reg_info =
 247             acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
 248         sleep_enable_reg_info =
 249             acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
 250
 251         /* Clear wake status */
 252
 253         status =
 254             acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS, ACPI_CLEAR_STATUS);
 255         if (ACPI_FAILURE(status)) {
 256                 return_ACPI_STATUS(status);
 257         }
 258
 259         /* Clear all fixed and general purpose status bits */
 260
 261         status = acpi_hw_clear_acpi_status();
 262         if (ACPI_FAILURE(status)) {
 263                 return_ACPI_STATUS(status);
 264         }
 265
 266         /*
 267          * 1) Disable/Clear all GPEs
 268          * 2) Enable all wakeup GPEs
 269          */
 270         status = acpi_hw_disable_all_gpes();
 271         if (ACPI_FAILURE(status)) {
 272                 return_ACPI_STATUS(status);
 273         }
 274         acpi_gbl_system_awake_and_running = FALSE;
 275
 276         status = acpi_hw_enable_all_wakeup_gpes();
 277         if (ACPI_FAILURE(status)) {
 278                 return_ACPI_STATUS(status);
 279         }
 280
 281         /* Execute the _GTS method */
 282
 283         arg_list.count = 1;
 284         arg_list.pointer = &arg;
 285         arg.type = ACPI_TYPE_INTEGER;
 286         arg.integer.value = sleep_state;
 287
 288         status = acpi_evaluate_object(NULL, METHOD_NAME__GTS, &arg_list, NULL);
 289         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 290                 return_ACPI_STATUS(status);
 291         }
 292
 293         /* Get current value of PM1A control */
 294
 295         status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
 296                                        &pm1a_control);
 297         if (ACPI_FAILURE(status)) {
 298                 return_ACPI_STATUS(status);
 299         }
 300         ACPI_DEBUG_PRINT((ACPI_DB_INIT,
 301                           "Entering sleep state [S%d]\n", sleep_state));
 302
 303         /* Clear the SLP_EN and SLP_TYP fields */
 304
 305         pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
 306                           sleep_enable_reg_info->access_bit_mask);
 307         pm1b_control = pm1a_control;
 308
 309         /* Insert the SLP_TYP bits */
 310
 311         pm1a_control |=
 312             (acpi_gbl_sleep_type_a << sleep_type_reg_info->bit_position);
 313         pm1b_control |=
 314             (acpi_gbl_sleep_type_b << sleep_type_reg_info->bit_position);
 315
 316         /*
 317          * We split the writes of SLP_TYP and SLP_EN to workaround
 318          * poorly implemented hardware.
 319          */
 320
 321         /* Write #1: write the SLP_TYP data to the PM1 Control registers */
 322
 323         status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
 324         if (ACPI_FAILURE(status)) {
 325                 return_ACPI_STATUS(status);
 326         }
 327
 328         /* Insert the sleep enable (SLP_EN) bit */
 329
 330         pm1a_control |= sleep_enable_reg_info->access_bit_mask;
 331         pm1b_control |= sleep_enable_reg_info->access_bit_mask;
 332
 333         /* Flush caches, as per ACPI specification */
 334
 335         ACPI_FLUSH_CPU_CACHE();
 336
 337         /* Write #2: Write both SLP_TYP + SLP_EN */
 338
 339         status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
 340         if (ACPI_FAILURE(status)) {
 341                 return_ACPI_STATUS(status);
 342         }
 343
 344         if (sleep_state > ACPI_STATE_S3) {
 345                 /*
 346                  * We wanted to sleep > S3, but it didn't happen (by virtue of the
 347                  * fact that we are still executing!)
 348                  *
 349                  * Wait ten seconds, then try again. This is to get S4/S5 to work on
 350                  * all machines.
 351                  *
 352                  * We wait so long to allow chipsets that poll this reg very slowly
 353                  * to still read the right value. Ideally, this block would go
 354                  * away entirely.
 355                  */
 356                 acpi_os_stall(10000000);
 357
 358                 status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
 359                                                 sleep_enable_reg_info->
 360                                                 access_bit_mask);
 361                 if (ACPI_FAILURE(status)) {
 362                         return_ACPI_STATUS(status);
 363                 }
 364         }
 365
 366         /* Wait until we enter sleep state */
 367
 368         do {
 369                 status = acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS,
 370                                                     &in_value);
 371                 if (ACPI_FAILURE(status)) {
 372                         return_ACPI_STATUS(status);
 373                 }
 374
 375                 /* Spin until we wake */
 376
 377         } while (!in_value);
 378
 379         return_ACPI_STATUS(AE_OK);
 380 }
 381
 382 ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state)
 383
 384 /*******************************************************************************
 385  *
 386  * FUNCTION:    acpi_enter_sleep_state_s4bios
 387  *
 388  * PARAMETERS:  None
 389  *
 390  * RETURN:      Status
 391  *
 392  * DESCRIPTION: Perform a S4 bios request.
 393  *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
 394  *
 395  ******************************************************************************/
 396 acpi_status asmlinkage acpi_enter_sleep_state_s4bios(void)
 397 {
 398         u32 in_value;
 399         acpi_status status;
 400
 401         ACPI_FUNCTION_TRACE(acpi_enter_sleep_state_s4bios);
 402
 403         /* Clear the wake status bit (PM1) */
 404
 405         status =
 406             acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS, ACPI_CLEAR_STATUS);
 407         if (ACPI_FAILURE(status)) {
 408                 return_ACPI_STATUS(status);
 409         }
 410
 411         status = acpi_hw_clear_acpi_status();
 412         if (ACPI_FAILURE(status)) {
 413                 return_ACPI_STATUS(status);
 414         }
 415
 416         /*
 417          * 1) Disable/Clear all GPEs
 418          * 2) Enable all wakeup GPEs
 419          */
 420         status = acpi_hw_disable_all_gpes();
 421         if (ACPI_FAILURE(status)) {
 422                 return_ACPI_STATUS(status);
 423         }
 424         acpi_gbl_system_awake_and_running = FALSE;
 425
 426         status = acpi_hw_enable_all_wakeup_gpes();
 427         if (ACPI_FAILURE(status)) {
 428                 return_ACPI_STATUS(status);
 429         }
 430
 431         ACPI_FLUSH_CPU_CACHE();
 432
 433         status = acpi_hw_write_port(acpi_gbl_FADT.smi_command,
 434                                     (u32) acpi_gbl_FADT.S4bios_request, 8);
 435
 436         do {
 437                 acpi_os_stall(1000);
 438                 status =
 439                     acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS, &in_value);
 440                 if (ACPI_FAILURE(status)) {
 441                         return_ACPI_STATUS(status);
 442                 }
 443         } while (!in_value);
 444
 445         return_ACPI_STATUS(AE_OK);
 446 }
 447
 448 ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state_s4bios)
 449
 450 /*******************************************************************************
 451  *
 452  * FUNCTION:    acpi_leave_sleep_state_prep
 453  *
 454  * PARAMETERS:  sleep_state         - Which sleep state we are exiting
 455  *
 456  * RETURN:      Status
 457  *
 458  * DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
 459  *              sleep.
 460  *              Called with interrupts DISABLED.
 461  *
 462  ******************************************************************************/
 463 acpi_status acpi_leave_sleep_state_prep(u8 sleep_state)
 464 {
 465         struct acpi_object_list arg_list;
 466         union acpi_object arg;
 467         acpi_status status;
 468         struct acpi_bit_register_info *sleep_type_reg_info;
 469         struct acpi_bit_register_info *sleep_enable_reg_info;
 470         u32 pm1a_control;
 471         u32 pm1b_control;
 472
 473         ACPI_FUNCTION_TRACE(acpi_leave_sleep_state_prep);
 474
 475         /*
 476          * Set SLP_TYPE and SLP_EN to state S0.
 477          * This is unclear from the ACPI Spec, but it is required
 478          * by some machines.
 479          */
 480         status = acpi_get_sleep_type_data(ACPI_STATE_S0,
 481                                           &acpi_gbl_sleep_type_a,
 482                                           &acpi_gbl_sleep_type_b);
 483         if (ACPI_SUCCESS(status)) {
 484                 sleep_type_reg_info =
 485                     acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
 486                 sleep_enable_reg_info =
 487                     acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
 488
 489                 /* Get current value of PM1A control */
 490
 491                 status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
 492                                                &pm1a_control);
 493                 if (ACPI_SUCCESS(status)) {
 494
 495                         /* Clear the SLP_EN and SLP_TYP fields */
 496
 497                         pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
 498                                           sleep_enable_reg_info->
 499                                           access_bit_mask);
 500                         pm1b_control = pm1a_control;
 501
 502                         /* Insert the SLP_TYP bits */
 503
 504                         pm1a_control |= (acpi_gbl_sleep_type_a <<
 505                                          sleep_type_reg_info->bit_position);
 506                         pm1b_control |= (acpi_gbl_sleep_type_b <<
 507                                          sleep_type_reg_info->bit_position);
 508
 509                         /* Write the control registers and ignore any errors */
 510
 511                         (void)acpi_hw_write_pm1_control(pm1a_control,
 512                                                         pm1b_control);
 513                 }
 514         }
 515
 516         /* Execute the _BFS method */
 517
 518         arg_list.count = 1;
 519         arg_list.pointer = &arg;
 520         arg.type = ACPI_TYPE_INTEGER;
 521         arg.integer.value = sleep_state;
 522
 523         status = acpi_evaluate_object(NULL, METHOD_NAME__BFS, &arg_list, NULL);
 524         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 525                 ACPI_EXCEPTION((AE_INFO, status, "During Method _BFS"));
 526         }
 527
 528         return_ACPI_STATUS(status);
 529 }
 530
 531 /*******************************************************************************
 532  *
 533  * FUNCTION:    acpi_leave_sleep_state
 534  *
 535  * PARAMETERS:  sleep_state         - Which sleep state we just exited
 536  *
 537  * RETURN:      Status
 538  *
 539  * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
 540  *              Called with interrupts ENABLED.
 541  *
 542  ******************************************************************************/
 543 acpi_status acpi_leave_sleep_state(u8 sleep_state)
 544 {
 545         struct acpi_object_list arg_list;
 546         union acpi_object arg;
 547         acpi_status status;
 548
 549         ACPI_FUNCTION_TRACE(acpi_leave_sleep_state);
 550
 551         /* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
 552
 553         acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
 554
 555         /* Setup parameter object */
 556
 557         arg_list.count = 1;
 558         arg_list.pointer = &arg;
 559         arg.type = ACPI_TYPE_INTEGER;
 560
 561         /* Ignore any errors from these methods */
 562
 563         arg.integer.value = ACPI_SST_WAKING;
 564         status = acpi_evaluate_object(NULL, METHOD_NAME__SST, &arg_list, NULL);
 565         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 566                 ACPI_EXCEPTION((AE_INFO, status, "During Method _SST"));
 567         }
 568
 569         /*
 570          * GPEs must be enabled before _WAK is called as GPEs
 571          * might get fired there
 572          *
 573          * Restore the GPEs:
 574          * 1) Disable/Clear all GPEs
 575          * 2) Enable all runtime GPEs
 576          */
 577         status = acpi_hw_disable_all_gpes();
 578         if (ACPI_FAILURE(status)) {
 579                 return_ACPI_STATUS(status);
 580         }
 581         status = acpi_hw_enable_all_runtime_gpes();
 582         if (ACPI_FAILURE(status)) {
 583                 return_ACPI_STATUS(status);
 584         }
 585
 586         arg.integer.value = sleep_state;
 587         status = acpi_evaluate_object(NULL, METHOD_NAME__WAK, &arg_list, NULL);
 588         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 589                 ACPI_EXCEPTION((AE_INFO, status, "During Method _WAK"));
 590         }
 591         /* TBD: _WAK "sometimes" returns stuff - do we want to look at it? */
 592
 593         /*
 594          * Some BIOSes assume that WAK_STS will be cleared on resume and use
 595          * it to determine whether the system is rebooting or resuming. Clear
 596          * it for compatibility.
 597          */
 598         acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS, 1);
 599
 600         acpi_gbl_system_awake_and_running = TRUE;
 601
 602         /* Enable power button */
 603
 604         (void)
 605             acpi_write_bit_register(acpi_gbl_fixed_event_info
 606                               [ACPI_EVENT_POWER_BUTTON].
 607                               enable_register_id, ACPI_ENABLE_EVENT);
 608
 609         (void)
 610             acpi_write_bit_register(acpi_gbl_fixed_event_info
 611                               [ACPI_EVENT_POWER_BUTTON].
 612                               status_register_id, ACPI_CLEAR_STATUS);
 613
 614         arg.integer.value = ACPI_SST_WORKING;
 615         status = acpi_evaluate_object(NULL, METHOD_NAME__SST, &arg_list, NULL);
 616         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 617                 ACPI_EXCEPTION((AE_INFO, status, "During Method _SST"));
 618         }
 619
 620         return_ACPI_STATUS(status);
 621 }
 622
 623 ACPI_EXPORT_SYMBOL(acpi_leave_sleep_state)