drivers/acpi/sleep.c

   1 /*
   2  * sleep.c - ACPI sleep support.
   3  *
   4  * Copyright (c) 2005 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
   5  * Copyright (c) 2004 David Shaohua Li <shaohua.li@intel.com>
   6  * Copyright (c) 2000-2003 Patrick Mochel
   7  * Copyright (c) 2003 Open Source Development Lab
   8  *
   9  * This file is released under the GPLv2.
  10  *
  11  */
  12
  13 #include <linux/delay.h>
  14 #include <linux/irq.h>
  15 #include <linux/dmi.h>
  16 #include <linux/device.h>
  17 #include <linux/suspend.h>
  18 #include <linux/reboot.h>
  19 #include <linux/acpi.h>
  20 #include <linux/module.h>
  21
  22 #include <asm/io.h>
  23
  24 #include <acpi/acpi_bus.h>
  25 #include <acpi/acpi_drivers.h>
  26
  27 #include "internal.h"
  28 #include "sleep.h"
  29
  30 static u8 sleep_states[ACPI_S_STATE_COUNT];
  31
  32 static void acpi_sleep_tts_switch(u32 acpi_state)
  33 {
  34         union acpi_object in_arg = { ACPI_TYPE_INTEGER };
  35         struct acpi_object_list arg_list = { 1, &in_arg };
  36         acpi_status status = AE_OK;
  37
  38         in_arg.integer.value = acpi_state;
  39         status = acpi_evaluate_object(NULL, "\\_TTS", &arg_list, NULL);
  40         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
  41                 /*
  42                  * OS can't evaluate the _TTS object correctly. Some warning
  43                  * message will be printed. But it won't break anything.
  44                  */
  45                 printk(KERN_NOTICE "Failure in evaluating _TTS object\n");
  46         }
  47 }
  48
  49 static int tts_notify_reboot(struct notifier_block *this,
  50                         unsigned long code, void *x)
  51 {
  52         acpi_sleep_tts_switch(ACPI_STATE_S5);
  53         return NOTIFY_DONE;
  54 }
  55
  56 static struct notifier_block tts_notifier = {
  57         .notifier_call  = tts_notify_reboot,
  58         .next           = NULL,
  59         .priority       = 0,
  60 };
  61
  62 static int acpi_sleep_prepare(u32 acpi_state)
  63 {
  64 #ifdef CONFIG_ACPI_SLEEP
  65         /* do we have a wakeup address for S2 and S3? */
  66         if (acpi_state == ACPI_STATE_S3) {
  67                 if (!acpi_wakeup_address)
  68                         return -EFAULT;
  69                 acpi_set_firmware_waking_vector(acpi_wakeup_address);
  70
  71         }
  72         ACPI_FLUSH_CPU_CACHE();
  73 #endif
  74         printk(KERN_INFO PREFIX "Preparing to enter system sleep state S%d\n",
  75                 acpi_state);
  76         acpi_enable_wakeup_devices(acpi_state);
  77         acpi_enter_sleep_state_prep(acpi_state);
  78         return 0;
  79 }
  80
  81 #ifdef CONFIG_ACPI_SLEEP
  82 static u32 acpi_target_sleep_state = ACPI_STATE_S0;
  83
  84 u32 acpi_target_system_state(void)
  85 {
  86         return acpi_target_sleep_state;
  87 }
  88
  89 static bool pwr_btn_event_pending;
  90
  91 /*
  92  * The ACPI specification wants us to save NVS memory regions during hibernation
  93  * and to restore them during the subsequent resume.  Windows does that also for
  94  * suspend to RAM.  However, it is known that this mechanism does not work on
  95  * all machines, so we allow the user to disable it with the help of the
  96  * 'acpi_sleep=nonvs' kernel command line option.
  97  */
  98 static bool nvs_nosave;
  99
 100 void __init acpi_nvs_nosave(void)
 101 {
 102         nvs_nosave = true;
 103 }
 104
 105 /*
 106  * The ACPI specification wants us to save NVS memory regions during hibernation
 107  * but says nothing about saving NVS during S3.  Not all versions of Windows
 108  * save NVS on S3 suspend either, and it is clear that not all systems need
 109  * NVS to be saved at S3 time.  To improve suspend/resume time, allow the
 110  * user to disable saving NVS on S3 if their system does not require it, but
 111  * continue to save/restore NVS for S4 as specified.
 112  */
 113 static bool nvs_nosave_s3;
 114
 115 void __init acpi_nvs_nosave_s3(void)
 116 {
 117         nvs_nosave_s3 = true;
 118 }
 119
 120 /*
 121  * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
 122  * user to request that behavior by using the 'acpi_old_suspend_ordering'
 123  * kernel command line option that causes the following variable to be set.
 124  */
 125 static bool old_suspend_ordering;
 126
 127 void __init acpi_old_suspend_ordering(void)
 128 {
 129         old_suspend_ordering = true;
 130 }
 131
 132 static int __init init_old_suspend_ordering(const struct dmi_system_id *d)
 133 {
 134         acpi_old_suspend_ordering();
 135         return 0;
 136 }
 137
 138 static int __init init_nvs_nosave(const struct dmi_system_id *d)
 139 {
 140         acpi_nvs_nosave();
 141         return 0;
 142 }
 143
 144 static struct dmi_system_id __initdata acpisleep_dmi_table[] = {
 145         {
 146         .callback = init_old_suspend_ordering,
 147         .ident = "Abit KN9 (nForce4 variant)",
 148         .matches = {
 149                 DMI_MATCH(DMI_BOARD_VENDOR, "http://www.abit.com.tw/"),
 150                 DMI_MATCH(DMI_BOARD_NAME, "KN9 Series(NF-CK804)"),
 151                 },
 152         },
 153         {
 154         .callback = init_old_suspend_ordering,
 155         .ident = "HP xw4600 Workstation",
 156         .matches = {
 157                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 158                 DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
 159                 },
 160         },
 161         {
 162         .callback = init_old_suspend_ordering,
 163         .ident = "Asus Pundit P1-AH2 (M2N8L motherboard)",
 164         .matches = {
 165                 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTek Computer INC."),
 166                 DMI_MATCH(DMI_BOARD_NAME, "M2N8L"),
 167                 },
 168         },
 169         {
 170         .callback = init_old_suspend_ordering,
 171         .ident = "Panasonic CF51-2L",
 172         .matches = {
 173                 DMI_MATCH(DMI_BOARD_VENDOR,
 174                                 "Matsushita Electric Industrial Co.,Ltd."),
 175                 DMI_MATCH(DMI_BOARD_NAME, "CF51-2L"),
 176                 },
 177         },
 178         {
 179         .callback = init_nvs_nosave,
 180         .ident = "Sony Vaio VGN-FW21E",
 181         .matches = {
 182                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 183                 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW21E"),
 184                 },
 185         },
 186         {
 187         .callback = init_nvs_nosave,
 188         .ident = "Sony Vaio VPCEB17FX",
 189         .matches = {
 190                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 191                 DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB17FX"),
 192                 },
 193         },
 194         {
 195         .callback = init_nvs_nosave,
 196         .ident = "Sony Vaio VGN-SR11M",
 197         .matches = {
 198                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 199                 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR11M"),
 200                 },
 201         },
 202         {
 203         .callback = init_nvs_nosave,
 204         .ident = "Everex StepNote Series",
 205         .matches = {
 206                 DMI_MATCH(DMI_SYS_VENDOR, "Everex Systems, Inc."),
 207                 DMI_MATCH(DMI_PRODUCT_NAME, "Everex StepNote Series"),
 208                 },
 209         },
 210         {
 211         .callback = init_nvs_nosave,
 212         .ident = "Sony Vaio VPCEB1Z1E",
 213         .matches = {
 214                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 215                 DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB1Z1E"),
 216                 },
 217         },
 218         {
 219         .callback = init_nvs_nosave,
 220         .ident = "Sony Vaio VGN-NW130D",
 221         .matches = {
 222                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 223                 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-NW130D"),
 224                 },
 225         },
 226         {
 227         .callback = init_nvs_nosave,
 228         .ident = "Sony Vaio VPCCW29FX",
 229         .matches = {
 230                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 231                 DMI_MATCH(DMI_PRODUCT_NAME, "VPCCW29FX"),
 232                 },
 233         },
 234         {
 235         .callback = init_nvs_nosave,
 236         .ident = "Averatec AV1020-ED2",
 237         .matches = {
 238                 DMI_MATCH(DMI_SYS_VENDOR, "AVERATEC"),
 239                 DMI_MATCH(DMI_PRODUCT_NAME, "1000 Series"),
 240                 },
 241         },
 242         {
 243         .callback = init_old_suspend_ordering,
 244         .ident = "Asus A8N-SLI DELUXE",
 245         .matches = {
 246                 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
 247                 DMI_MATCH(DMI_BOARD_NAME, "A8N-SLI DELUXE"),
 248                 },
 249         },
 250         {
 251         .callback = init_old_suspend_ordering,
 252         .ident = "Asus A8N-SLI Premium",
 253         .matches = {
 254                 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
 255                 DMI_MATCH(DMI_BOARD_NAME, "A8N-SLI Premium"),
 256                 },
 257         },
 258         {
 259         .callback = init_nvs_nosave,
 260         .ident = "Sony Vaio VGN-SR26GN_P",
 261         .matches = {
 262                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 263                 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR26GN_P"),
 264                 },
 265         },
 266         {
 267         .callback = init_nvs_nosave,
 268         .ident = "Sony Vaio VPCEB1S1E",
 269         .matches = {
 270                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 271                 DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB1S1E"),
 272                 },
 273         },
 274         {
 275         .callback = init_nvs_nosave,
 276         .ident = "Sony Vaio VGN-FW520F",
 277         .matches = {
 278                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 279                 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW520F"),
 280                 },
 281         },
 282         {
 283         .callback = init_nvs_nosave,
 284         .ident = "Asus K54C",
 285         .matches = {
 286                 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
 287                 DMI_MATCH(DMI_PRODUCT_NAME, "K54C"),
 288                 },
 289         },
 290         {
 291         .callback = init_nvs_nosave,
 292         .ident = "Asus K54HR",
 293         .matches = {
 294                 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
 295                 DMI_MATCH(DMI_PRODUCT_NAME, "K54HR"),
 296                 },
 297         },
 298         {},
 299 };
 300
 301 static void acpi_sleep_dmi_check(void)
 302 {
 303         dmi_check_system(acpisleep_dmi_table);
 304 }
 305
 306 /**
 307  * acpi_pm_freeze - Disable the GPEs and suspend EC transactions.
 308  */
 309 static int acpi_pm_freeze(void)
 310 {
 311         acpi_disable_all_gpes();
 312         acpi_os_wait_events_complete();
 313         acpi_ec_block_transactions();
 314         return 0;
 315 }
 316
 317 /**
 318  * acpi_pre_suspend - Enable wakeup devices, "freeze" EC and save NVS.
 319  */
 320 static int acpi_pm_pre_suspend(void)
 321 {
 322         acpi_pm_freeze();
 323         return suspend_nvs_save();
 324 }
 325
 326 /**
 327  *      __acpi_pm_prepare - Prepare the platform to enter the target state.
 328  *
 329  *      If necessary, set the firmware waking vector and do arch-specific
 330  *      nastiness to get the wakeup code to the waking vector.
 331  */
 332 static int __acpi_pm_prepare(void)
 333 {
 334         int error = acpi_sleep_prepare(acpi_target_sleep_state);
 335         if (error)
 336                 acpi_target_sleep_state = ACPI_STATE_S0;
 337
 338         return error;
 339 }
 340
 341 /**
 342  *      acpi_pm_prepare - Prepare the platform to enter the target sleep
 343  *              state and disable the GPEs.
 344  */
 345 static int acpi_pm_prepare(void)
 346 {
 347         int error = __acpi_pm_prepare();
 348         if (!error)
 349                 error = acpi_pm_pre_suspend();
 350
 351         return error;
 352 }
 353
 354 static int find_powerf_dev(struct device *dev, void *data)
 355 {
 356         struct acpi_device *device = to_acpi_device(dev);
 357         const char *hid = acpi_device_hid(device);
 358
 359         return !strcmp(hid, ACPI_BUTTON_HID_POWERF);
 360 }
 361
 362 /**
 363  *      acpi_pm_finish - Instruct the platform to leave a sleep state.
 364  *
 365  *      This is called after we wake back up (or if entering the sleep state
 366  *      failed).
 367  */
 368 static void acpi_pm_finish(void)
 369 {
 370         struct device *pwr_btn_dev;
 371         u32 acpi_state = acpi_target_sleep_state;
 372
 373         acpi_ec_unblock_transactions();
 374         suspend_nvs_free();
 375
 376         if (acpi_state == ACPI_STATE_S0)
 377                 return;
 378
 379         printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
 380                 acpi_state);
 381         acpi_disable_wakeup_devices(acpi_state);
 382         acpi_leave_sleep_state(acpi_state);
 383
 384         /* reset firmware waking vector */
 385         acpi_set_firmware_waking_vector((acpi_physical_address) 0);
 386
 387         acpi_target_sleep_state = ACPI_STATE_S0;
 388
 389         acpi_resume_power_resources();
 390
 391         /* If we were woken with the fixed power button, provide a small
 392          * hint to userspace in the form of a wakeup event on the fixed power
 393          * button device (if it can be found).
 394          *
 395          * We delay the event generation til now, as the PM layer requires
 396          * timekeeping to be running before we generate events. */
 397         if (!pwr_btn_event_pending)
 398                 return;
 399
 400         pwr_btn_event_pending = false;
 401         pwr_btn_dev = bus_find_device(&acpi_bus_type, NULL, NULL,
 402                                       find_powerf_dev);
 403         if (pwr_btn_dev) {
 404                 pm_wakeup_event(pwr_btn_dev, 0);
 405                 put_device(pwr_btn_dev);
 406         }
 407 }
 408
 409 /**
 410  *      acpi_pm_end - Finish up suspend sequence.
 411  */
 412 static void acpi_pm_end(void)
 413 {
 414         /*
 415          * This is necessary in case acpi_pm_finish() is not called during a
 416          * failing transition to a sleep state.
 417          */
 418         acpi_target_sleep_state = ACPI_STATE_S0;
 419         acpi_sleep_tts_switch(acpi_target_sleep_state);
 420 }
 421 #else /* !CONFIG_ACPI_SLEEP */
 422 #define acpi_target_sleep_state ACPI_STATE_S0
 423 static inline void acpi_sleep_dmi_check(void) {}
 424 #endif /* CONFIG_ACPI_SLEEP */
 425
 426 #ifdef CONFIG_SUSPEND
 427 static u32 acpi_suspend_states[] = {
 428         [PM_SUSPEND_ON] = ACPI_STATE_S0,
 429         [PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
 430         [PM_SUSPEND_MEM] = ACPI_STATE_S3,
 431         [PM_SUSPEND_MAX] = ACPI_STATE_S5
 432 };
 433
 434 /**
 435  *      acpi_suspend_begin - Set the target system sleep state to the state
 436  *              associated with given @pm_state, if supported.
 437  */
 438 static int acpi_suspend_begin(suspend_state_t pm_state)
 439 {
 440         u32 acpi_state = acpi_suspend_states[pm_state];
 441         int error = 0;
 442
 443         error = (nvs_nosave || nvs_nosave_s3) ? 0 : suspend_nvs_alloc();
 444         if (error)
 445                 return error;
 446
 447         if (sleep_states[acpi_state]) {
 448                 acpi_target_sleep_state = acpi_state;
 449                 acpi_sleep_tts_switch(acpi_target_sleep_state);
 450         } else {
 451                 printk(KERN_ERR "ACPI does not support this state: %d\n",
 452                         pm_state);
 453                 error = -ENOSYS;
 454         }
 455         return error;
 456 }
 457
 458 /**
 459  *      acpi_suspend_enter - Actually enter a sleep state.
 460  *      @pm_state: ignored
 461  *
 462  *      Flush caches and go to sleep. For STR we have to call arch-specific
 463  *      assembly, which in turn call acpi_enter_sleep_state().
 464  *      It's unfortunate, but it works. Please fix if you're feeling frisky.
 465  */
 466 static int acpi_suspend_enter(suspend_state_t pm_state)
 467 {
 468         acpi_status status = AE_OK;
 469         u32 acpi_state = acpi_target_sleep_state;
 470         int error;
 471
 472         ACPI_FLUSH_CPU_CACHE();
 473
 474         switch (acpi_state) {
 475         case ACPI_STATE_S1:
 476                 barrier();
 477                 status = acpi_enter_sleep_state(acpi_state);
 478                 break;
 479
 480         case ACPI_STATE_S3:
 481                 error = acpi_suspend_lowlevel();
 482                 if (error)
 483                         return error;
 484                 pr_info(PREFIX "Low-level resume complete\n");
 485                 break;
 486         }
 487
 488         /* This violates the spec but is required for bug compatibility. */
 489         acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
 490
 491         /* Reprogram control registers */
 492         acpi_leave_sleep_state_prep(acpi_state);
 493
 494         /* ACPI 3.0 specs (P62) says that it's the responsibility
 495          * of the OSPM to clear the status bit [ implying that the
 496          * POWER_BUTTON event should not reach userspace ]
 497          *
 498          * However, we do generate a small hint for userspace in the form of
 499          * a wakeup event. We flag this condition for now and generate the
 500          * event later, as we're currently too early in resume to be able to
 501          * generate wakeup events.
 502          */
 503         if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3)) {
 504                 acpi_event_status pwr_btn_status;
 505
 506                 acpi_get_event_status(ACPI_EVENT_POWER_BUTTON, &pwr_btn_status);
 507
 508                 if (pwr_btn_status & ACPI_EVENT_FLAG_SET) {
 509                         acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
 510                         /* Flag for later */
 511                         pwr_btn_event_pending = true;
 512                 }
 513         }
 514
 515         /*
 516          * Disable and clear GPE status before interrupt is enabled. Some GPEs
 517          * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
 518          * acpi_leave_sleep_state will reenable specific GPEs later
 519          */
 520         acpi_disable_all_gpes();
 521         /* Allow EC transactions to happen. */
 522         acpi_ec_unblock_transactions_early();
 523
 524         suspend_nvs_restore();
 525
 526         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 527 }
 528
 529 static int acpi_suspend_state_valid(suspend_state_t pm_state)
 530 {
 531         u32 acpi_state;
 532
 533         switch (pm_state) {
 534         case PM_SUSPEND_ON:
 535         case PM_SUSPEND_STANDBY:
 536         case PM_SUSPEND_MEM:
 537                 acpi_state = acpi_suspend_states[pm_state];
 538
 539                 return sleep_states[acpi_state];
 540         default:
 541                 return 0;
 542         }
 543 }
 544
 545 static const struct platform_suspend_ops acpi_suspend_ops = {
 546         .valid = acpi_suspend_state_valid,
 547         .begin = acpi_suspend_begin,
 548         .prepare_late = acpi_pm_prepare,
 549         .enter = acpi_suspend_enter,
 550         .wake = acpi_pm_finish,
 551         .end = acpi_pm_end,
 552 };
 553
 554 /**
 555  *      acpi_suspend_begin_old - Set the target system sleep state to the
 556  *              state associated with given @pm_state, if supported, and
 557  *              execute the _PTS control method.  This function is used if the
 558  *              pre-ACPI 2.0 suspend ordering has been requested.
 559  */
 560 static int acpi_suspend_begin_old(suspend_state_t pm_state)
 561 {
 562         int error = acpi_suspend_begin(pm_state);
 563         if (!error)
 564                 error = __acpi_pm_prepare();
 565
 566         return error;
 567 }
 568
 569 /*
 570  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 571  * been requested.
 572  */
 573 static const struct platform_suspend_ops acpi_suspend_ops_old = {
 574         .valid = acpi_suspend_state_valid,
 575         .begin = acpi_suspend_begin_old,
 576         .prepare_late = acpi_pm_pre_suspend,
 577         .enter = acpi_suspend_enter,
 578         .wake = acpi_pm_finish,
 579         .end = acpi_pm_end,
 580         .recover = acpi_pm_finish,
 581 };
 582
 583 static void acpi_sleep_suspend_setup(void)
 584 {
 585         int i;
 586
 587         for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++) {
 588                 acpi_status status;
 589                 u8 type_a, type_b;
 590
 591                 status = acpi_get_sleep_type_data(i, &type_a, &type_b);
 592                 if (ACPI_SUCCESS(status)) {
 593                         sleep_states[i] = 1;
 594                         pr_cont(" S%d", i);
 595                 }
 596         }
 597
 598         suspend_set_ops(old_suspend_ordering ?
 599                 &acpi_suspend_ops_old : &acpi_suspend_ops);
 600 }
 601 #else /* !CONFIG_SUSPEND */
 602 static inline void acpi_sleep_suspend_setup(void) {}
 603 #endif /* !CONFIG_SUSPEND */
 604
 605 #ifdef CONFIG_HIBERNATION
 606 static unsigned long s4_hardware_signature;
 607 static struct acpi_table_facs *facs;
 608 static bool nosigcheck;
 609
 610 void __init acpi_no_s4_hw_signature(void)
 611 {
 612         nosigcheck = true;
 613 }
 614
 615 static int acpi_hibernation_begin(void)
 616 {
 617         int error;
 618
 619         error = nvs_nosave ? 0 : suspend_nvs_alloc();
 620         if (!error) {
 621                 acpi_target_sleep_state = ACPI_STATE_S4;
 622                 acpi_sleep_tts_switch(acpi_target_sleep_state);
 623         }
 624
 625         return error;
 626 }
 627
 628 static int acpi_hibernation_enter(void)
 629 {
 630         acpi_status status = AE_OK;
 631
 632         ACPI_FLUSH_CPU_CACHE();
 633
 634         /* This shouldn't return.  If it returns, we have a problem */
 635         status = acpi_enter_sleep_state(ACPI_STATE_S4);
 636         /* Reprogram control registers */
 637         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 638
 639         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 640 }
 641
 642 static void acpi_hibernation_leave(void)
 643 {
 644         /*
 645          * If ACPI is not enabled by the BIOS and the boot kernel, we need to
 646          * enable it here.
 647          */
 648         acpi_enable();
 649         /* Reprogram control registers */
 650         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 651         /* Check the hardware signature */
 652         if (facs && s4_hardware_signature != facs->hardware_signature) {
 653                 printk(KERN_EMERG "ACPI: Hardware changed while hibernated, "
 654                         "cannot resume!\n");
 655                 panic("ACPI S4 hardware signature mismatch");
 656         }
 657         /* Restore the NVS memory area */
 658         suspend_nvs_restore();
 659         /* Allow EC transactions to happen. */
 660         acpi_ec_unblock_transactions_early();
 661 }
 662
 663 static void acpi_pm_thaw(void)
 664 {
 665         acpi_ec_unblock_transactions();
 666         acpi_enable_all_runtime_gpes();
 667 }
 668
 669 static const struct platform_hibernation_ops acpi_hibernation_ops = {
 670         .begin = acpi_hibernation_begin,
 671         .end = acpi_pm_end,
 672         .pre_snapshot = acpi_pm_prepare,
 673         .finish = acpi_pm_finish,
 674         .prepare = acpi_pm_prepare,
 675         .enter = acpi_hibernation_enter,
 676         .leave = acpi_hibernation_leave,
 677         .pre_restore = acpi_pm_freeze,
 678         .restore_cleanup = acpi_pm_thaw,
 679 };
 680
 681 /**
 682  *      acpi_hibernation_begin_old - Set the target system sleep state to
 683  *              ACPI_STATE_S4 and execute the _PTS control method.  This
 684  *              function is used if the pre-ACPI 2.0 suspend ordering has been
 685  *              requested.
 686  */
 687 static int acpi_hibernation_begin_old(void)
 688 {
 689         int error;
 690         /*
 691          * The _TTS object should always be evaluated before the _PTS object.
 692          * When the old_suspended_ordering is true, the _PTS object is
 693          * evaluated in the acpi_sleep_prepare.
 694          */
 695         acpi_sleep_tts_switch(ACPI_STATE_S4);
 696
 697         error = acpi_sleep_prepare(ACPI_STATE_S4);
 698
 699         if (!error) {
 700                 if (!nvs_nosave)
 701                         error = suspend_nvs_alloc();
 702                 if (!error)
 703                         acpi_target_sleep_state = ACPI_STATE_S4;
 704         }
 705         return error;
 706 }
 707
 708 /*
 709  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 710  * been requested.
 711  */
 712 static const struct platform_hibernation_ops acpi_hibernation_ops_old = {
 713         .begin = acpi_hibernation_begin_old,
 714         .end = acpi_pm_end,
 715         .pre_snapshot = acpi_pm_pre_suspend,
 716         .prepare = acpi_pm_freeze,
 717         .finish = acpi_pm_finish,
 718         .enter = acpi_hibernation_enter,
 719         .leave = acpi_hibernation_leave,
 720         .pre_restore = acpi_pm_freeze,
 721         .restore_cleanup = acpi_pm_thaw,
 722         .recover = acpi_pm_finish,
 723 };
 724
 725 static void acpi_sleep_hibernate_setup(void)
 726 {
 727         acpi_status status;
 728         u8 type_a, type_b;
 729
 730         status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b);
 731         if (ACPI_FAILURE(status))
 732                 return;
 733
 734         hibernation_set_ops(old_suspend_ordering ?
 735                         &acpi_hibernation_ops_old : &acpi_hibernation_ops);
 736         sleep_states[ACPI_STATE_S4] = 1;
 737         pr_cont(KERN_CONT " S4");
 738         if (nosigcheck)
 739                 return;
 740
 741         acpi_get_table(ACPI_SIG_FACS, 1, (struct acpi_table_header **)&facs);
 742         if (facs)
 743                 s4_hardware_signature = facs->hardware_signature;
 744 }
 745 #else /* !CONFIG_HIBERNATION */
 746 static inline void acpi_sleep_hibernate_setup(void) {}
 747 #endif /* !CONFIG_HIBERNATION */
 748
 749 int acpi_suspend(u32 acpi_state)
 750 {
 751         suspend_state_t states[] = {
 752                 [1] = PM_SUSPEND_STANDBY,
 753                 [3] = PM_SUSPEND_MEM,
 754                 [5] = PM_SUSPEND_MAX
 755         };
 756
 757         if (acpi_state < 6 && states[acpi_state])
 758                 return pm_suspend(states[acpi_state]);
 759         if (acpi_state == 4)
 760                 return hibernate();
 761         return -EINVAL;
 762 }
 763
 764 static void acpi_power_off_prepare(void)
 765 {
 766         /* Prepare to power off the system */
 767         acpi_sleep_prepare(ACPI_STATE_S5);
 768         acpi_disable_all_gpes();
 769 }
 770
 771 static void acpi_power_off(void)
 772 {
 773         /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
 774         printk(KERN_DEBUG "%s called\n", __func__);
 775         local_irq_disable();
 776         acpi_enter_sleep_state(ACPI_STATE_S5);
 777 }
 778
 779 int __init acpi_sleep_init(void)
 780 {
 781         acpi_status status;
 782         u8 type_a, type_b;
 783
 784         if (acpi_disabled)
 785                 return 0;
 786
 787         acpi_sleep_dmi_check();
 788
 789         sleep_states[ACPI_STATE_S0] = 1;
 790         pr_info(PREFIX "(supports S0");
 791
 792         acpi_sleep_suspend_setup();
 793         acpi_sleep_hibernate_setup();
 794
 795         status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
 796         if (ACPI_SUCCESS(status)) {
 797                 sleep_states[ACPI_STATE_S5] = 1;
 798                 pr_cont(" S5");
 799                 pm_power_off_prepare = acpi_power_off_prepare;
 800                 pm_power_off = acpi_power_off;
 801         }
 802         pr_cont(")\n");
 803         /*
 804          * Register the tts_notifier to reboot notifier list so that the _TTS
 805          * object can also be evaluated when the system enters S5.
 806          */
 807         register_reboot_notifier(&tts_notifier);
 808         return 0;
 809 }