drivers/acpi/sleep.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * sleep.c - ACPI sleep support.
   4  *
   5  * Copyright (c) 2005 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
   6  * Copyright (c) 2004 David Shaohua Li <shaohua.li@intel.com>
   7  * Copyright (c) 2000-2003 Patrick Mochel
   8  * Copyright (c) 2003 Open Source Development Lab
   9  */
  10
  11 #include <linux/delay.h>
  12 #include <linux/irq.h>
  13 #include <linux/dmi.h>
  14 #include <linux/device.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/suspend.h>
  17 #include <linux/reboot.h>
  18 #include <linux/acpi.h>
  19 #include <linux/module.h>
  20 #include <linux/syscore_ops.h>
  21 #include <asm/io.h>
  22 #include <trace/events/power.h>
  23
  24 #include "internal.h"
  25 #include "sleep.h"
  26
  27 /*
  28  * Some HW-full platforms do not have _S5, so they may need
  29  * to leverage efi power off for a shutdown.
  30  */
  31 bool acpi_no_s5;
  32 static u8 sleep_states[ACPI_S_STATE_COUNT];
  33
  34 static void acpi_sleep_tts_switch(u32 acpi_state)
  35 {
  36         acpi_status status;
  37
  38         status = acpi_execute_simple_method(NULL, "\\_TTS", acpi_state);
  39         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
  40                 /*
  41                  * OS can't evaluate the _TTS object correctly. Some warning
  42                  * message will be printed. But it won't break anything.
  43                  */
  44                 printk(KERN_NOTICE "Failure in evaluating _TTS object\n");
  45         }
  46 }
  47
  48 static int tts_notify_reboot(struct notifier_block *this,
  49                         unsigned long code, void *x)
  50 {
  51         acpi_sleep_tts_switch(ACPI_STATE_S5);
  52         return NOTIFY_DONE;
  53 }
  54
  55 static struct notifier_block tts_notifier = {
  56         .notifier_call  = tts_notify_reboot,
  57         .next           = NULL,
  58         .priority       = 0,
  59 };
  60
  61 static int acpi_sleep_prepare(u32 acpi_state)
  62 {
  63 #ifdef CONFIG_ACPI_SLEEP
  64         /* do we have a wakeup address for S2 and S3? */
  65         if (acpi_state == ACPI_STATE_S3) {
  66                 if (!acpi_wakeup_address)
  67                         return -EFAULT;
  68                 acpi_set_waking_vector(acpi_wakeup_address);
  69
  70         }
  71         ACPI_FLUSH_CPU_CACHE();
  72 #endif
  73         printk(KERN_INFO PREFIX "Preparing to enter system sleep state S%d\n",
  74                 acpi_state);
  75         acpi_enable_wakeup_devices(acpi_state);
  76         acpi_enter_sleep_state_prep(acpi_state);
  77         return 0;
  78 }
  79
  80 bool acpi_sleep_state_supported(u8 sleep_state)
  81 {
  82         acpi_status status;
  83         u8 type_a, type_b;
  84
  85         status = acpi_get_sleep_type_data(sleep_state, &type_a, &type_b);
  86         return ACPI_SUCCESS(status) && (!acpi_gbl_reduced_hardware
  87                 || (acpi_gbl_FADT.sleep_control.address
  88                         && acpi_gbl_FADT.sleep_status.address));
  89 }
  90
  91 #ifdef CONFIG_ACPI_SLEEP
  92 static bool sleep_no_lps0 __read_mostly;
  93 module_param(sleep_no_lps0, bool, 0644);
  94 MODULE_PARM_DESC(sleep_no_lps0, "Do not use the special LPS0 device interface");
  95
  96 static u32 acpi_target_sleep_state = ACPI_STATE_S0;
  97
  98 u32 acpi_target_system_state(void)
  99 {
 100         return acpi_target_sleep_state;
 101 }
 102 EXPORT_SYMBOL_GPL(acpi_target_system_state);
 103
 104 static bool pwr_btn_event_pending;
 105
 106 /*
 107  * The ACPI specification wants us to save NVS memory regions during hibernation
 108  * and to restore them during the subsequent resume.  Windows does that also for
 109  * suspend to RAM.  However, it is known that this mechanism does not work on
 110  * all machines, so we allow the user to disable it with the help of the
 111  * 'acpi_sleep=nonvs' kernel command line option.
 112  */
 113 static bool nvs_nosave;
 114
 115 void __init acpi_nvs_nosave(void)
 116 {
 117         nvs_nosave = true;
 118 }
 119
 120 /*
 121  * The ACPI specification wants us to save NVS memory regions during hibernation
 122  * but says nothing about saving NVS during S3.  Not all versions of Windows
 123  * save NVS on S3 suspend either, and it is clear that not all systems need
 124  * NVS to be saved at S3 time.  To improve suspend/resume time, allow the
 125  * user to disable saving NVS on S3 if their system does not require it, but
 126  * continue to save/restore NVS for S4 as specified.
 127  */
 128 static bool nvs_nosave_s3;
 129
 130 void __init acpi_nvs_nosave_s3(void)
 131 {
 132         nvs_nosave_s3 = true;
 133 }
 134
 135 static int __init init_nvs_save_s3(const struct dmi_system_id *d)
 136 {
 137         nvs_nosave_s3 = false;
 138         return 0;
 139 }
 140
 141 /*
 142  * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
 143  * user to request that behavior by using the 'acpi_old_suspend_ordering'
 144  * kernel command line option that causes the following variable to be set.
 145  */
 146 static bool old_suspend_ordering;
 147
 148 void __init acpi_old_suspend_ordering(void)
 149 {
 150         old_suspend_ordering = true;
 151 }
 152
 153 static int __init init_old_suspend_ordering(const struct dmi_system_id *d)
 154 {
 155         acpi_old_suspend_ordering();
 156         return 0;
 157 }
 158
 159 static int __init init_nvs_nosave(const struct dmi_system_id *d)
 160 {
 161         acpi_nvs_nosave();
 162         return 0;
 163 }
 164
 165 static bool acpi_sleep_default_s3;
 166
 167 static int __init init_default_s3(const struct dmi_system_id *d)
 168 {
 169         acpi_sleep_default_s3 = true;
 170         return 0;
 171 }
 172
 173 static const struct dmi_system_id acpisleep_dmi_table[] __initconst = {
 174         {
 175         .callback = init_old_suspend_ordering,
 176         .ident = "Abit KN9 (nForce4 variant)",
 177         .matches = {
 178                 DMI_MATCH(DMI_BOARD_VENDOR, "http://www.abit.com.tw/"),
 179                 DMI_MATCH(DMI_BOARD_NAME, "KN9 Series(NF-CK804)"),
 180                 },
 181         },
 182         {
 183         .callback = init_old_suspend_ordering,
 184         .ident = "HP xw4600 Workstation",
 185         .matches = {
 186                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 187                 DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
 188                 },
 189         },
 190         {
 191         .callback = init_old_suspend_ordering,
 192         .ident = "Asus Pundit P1-AH2 (M2N8L motherboard)",
 193         .matches = {
 194                 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTek Computer INC."),
 195                 DMI_MATCH(DMI_BOARD_NAME, "M2N8L"),
 196                 },
 197         },
 198         {
 199         .callback = init_old_suspend_ordering,
 200         .ident = "Panasonic CF51-2L",
 201         .matches = {
 202                 DMI_MATCH(DMI_BOARD_VENDOR,
 203                                 "Matsushita Electric Industrial Co.,Ltd."),
 204                 DMI_MATCH(DMI_BOARD_NAME, "CF51-2L"),
 205                 },
 206         },
 207         {
 208         .callback = init_nvs_nosave,
 209         .ident = "Sony Vaio VGN-FW41E_H",
 210         .matches = {
 211                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 212                 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW41E_H"),
 213                 },
 214         },
 215         {
 216         .callback = init_nvs_nosave,
 217         .ident = "Sony Vaio VGN-FW21E",
 218         .matches = {
 219                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 220                 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW21E"),
 221                 },
 222         },
 223         {
 224         .callback = init_nvs_nosave,
 225         .ident = "Sony Vaio VGN-FW21M",
 226         .matches = {
 227                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 228                 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW21M"),
 229                 },
 230         },
 231         {
 232         .callback = init_nvs_nosave,
 233         .ident = "Sony Vaio VPCEB17FX",
 234         .matches = {
 235                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 236                 DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB17FX"),
 237                 },
 238         },
 239         {
 240         .callback = init_nvs_nosave,
 241         .ident = "Sony Vaio VGN-SR11M",
 242         .matches = {
 243                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 244                 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR11M"),
 245                 },
 246         },
 247         {
 248         .callback = init_nvs_nosave,
 249         .ident = "Everex StepNote Series",
 250         .matches = {
 251                 DMI_MATCH(DMI_SYS_VENDOR, "Everex Systems, Inc."),
 252                 DMI_MATCH(DMI_PRODUCT_NAME, "Everex StepNote Series"),
 253                 },
 254         },
 255         {
 256         .callback = init_nvs_nosave,
 257         .ident = "Sony Vaio VPCEB1Z1E",
 258         .matches = {
 259                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 260                 DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB1Z1E"),
 261                 },
 262         },
 263         {
 264         .callback = init_nvs_nosave,
 265         .ident = "Sony Vaio VGN-NW130D",
 266         .matches = {
 267                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 268                 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-NW130D"),
 269                 },
 270         },
 271         {
 272         .callback = init_nvs_nosave,
 273         .ident = "Sony Vaio VPCCW29FX",
 274         .matches = {
 275                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 276                 DMI_MATCH(DMI_PRODUCT_NAME, "VPCCW29FX"),
 277                 },
 278         },
 279         {
 280         .callback = init_nvs_nosave,
 281         .ident = "Averatec AV1020-ED2",
 282         .matches = {
 283                 DMI_MATCH(DMI_SYS_VENDOR, "AVERATEC"),
 284                 DMI_MATCH(DMI_PRODUCT_NAME, "1000 Series"),
 285                 },
 286         },
 287         {
 288         .callback = init_old_suspend_ordering,
 289         .ident = "Asus A8N-SLI DELUXE",
 290         .matches = {
 291                 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
 292                 DMI_MATCH(DMI_BOARD_NAME, "A8N-SLI DELUXE"),
 293                 },
 294         },
 295         {
 296         .callback = init_old_suspend_ordering,
 297         .ident = "Asus A8N-SLI Premium",
 298         .matches = {
 299                 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
 300                 DMI_MATCH(DMI_BOARD_NAME, "A8N-SLI Premium"),
 301                 },
 302         },
 303         {
 304         .callback = init_nvs_nosave,
 305         .ident = "Sony Vaio VGN-SR26GN_P",
 306         .matches = {
 307                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 308                 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR26GN_P"),
 309                 },
 310         },
 311         {
 312         .callback = init_nvs_nosave,
 313         .ident = "Sony Vaio VPCEB1S1E",
 314         .matches = {
 315                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 316                 DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB1S1E"),
 317                 },
 318         },
 319         {
 320         .callback = init_nvs_nosave,
 321         .ident = "Sony Vaio VGN-FW520F",
 322         .matches = {
 323                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 324                 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW520F"),
 325                 },
 326         },
 327         {
 328         .callback = init_nvs_nosave,
 329         .ident = "Asus K54C",
 330         .matches = {
 331                 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
 332                 DMI_MATCH(DMI_PRODUCT_NAME, "K54C"),
 333                 },
 334         },
 335         {
 336         .callback = init_nvs_nosave,
 337         .ident = "Asus K54HR",
 338         .matches = {
 339                 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
 340                 DMI_MATCH(DMI_PRODUCT_NAME, "K54HR"),
 341                 },
 342         },
 343         {
 344         .callback = init_nvs_save_s3,
 345         .ident = "Asus 1025C",
 346         .matches = {
 347                 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
 348                 DMI_MATCH(DMI_PRODUCT_NAME, "1025C"),
 349                 },
 350         },
 351         /*
 352          * https://bugzilla.kernel.org/show_bug.cgi?id=189431
 353          * Lenovo G50-45 is a platform later than 2012, but needs nvs memory
 354          * saving during S3.
 355          */
 356         {
 357         .callback = init_nvs_save_s3,
 358         .ident = "Lenovo G50-45",
 359         .matches = {
 360                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 361                 DMI_MATCH(DMI_PRODUCT_NAME, "80E3"),
 362                 },
 363         },
 364         /*
 365          * https://bugzilla.kernel.org/show_bug.cgi?id=196907
 366          * Some Dell XPS13 9360 cannot do suspend-to-idle using the Low Power
 367          * S0 Idle firmware interface.
 368          */
 369         {
 370         .callback = init_default_s3,
 371         .ident = "Dell XPS13 9360",
 372         .matches = {
 373                 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 374                 DMI_MATCH(DMI_PRODUCT_NAME, "XPS 13 9360"),
 375                 },
 376         },
 377         /*
 378          * ThinkPad X1 Tablet(2016) cannot do suspend-to-idle using
 379          * the Low Power S0 Idle firmware interface (see
 380          * https://bugzilla.kernel.org/show_bug.cgi?id=199057).
 381          */
 382         {
 383         .callback = init_default_s3,
 384         .ident = "ThinkPad X1 Tablet(2016)",
 385         .matches = {
 386                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 387                 DMI_MATCH(DMI_PRODUCT_NAME, "20GGA00L00"),
 388                 },
 389         },
 390         {},
 391 };
 392
 393 static bool ignore_blacklist;
 394
 395 void __init acpi_sleep_no_blacklist(void)
 396 {
 397         ignore_blacklist = true;
 398 }
 399
 400 static void __init acpi_sleep_dmi_check(void)
 401 {
 402         if (ignore_blacklist)
 403                 return;
 404
 405         if (dmi_get_bios_year() >= 2012)
 406                 acpi_nvs_nosave_s3();
 407
 408         dmi_check_system(acpisleep_dmi_table);
 409 }
 410
 411 /**
 412  * acpi_pm_freeze - Disable the GPEs and suspend EC transactions.
 413  */
 414 static int acpi_pm_freeze(void)
 415 {
 416         acpi_disable_all_gpes();
 417         acpi_os_wait_events_complete();
 418         acpi_ec_block_transactions();
 419         return 0;
 420 }
 421
 422 /**
 423  * acpi_pre_suspend - Enable wakeup devices, "freeze" EC and save NVS.
 424  */
 425 static int acpi_pm_pre_suspend(void)
 426 {
 427         acpi_pm_freeze();
 428         return suspend_nvs_save();
 429 }
 430
 431 /**
 432  *      __acpi_pm_prepare - Prepare the platform to enter the target state.
 433  *
 434  *      If necessary, set the firmware waking vector and do arch-specific
 435  *      nastiness to get the wakeup code to the waking vector.
 436  */
 437 static int __acpi_pm_prepare(void)
 438 {
 439         int error = acpi_sleep_prepare(acpi_target_sleep_state);
 440         if (error)
 441                 acpi_target_sleep_state = ACPI_STATE_S0;
 442
 443         return error;
 444 }
 445
 446 /**
 447  *      acpi_pm_prepare - Prepare the platform to enter the target sleep
 448  *              state and disable the GPEs.
 449  */
 450 static int acpi_pm_prepare(void)
 451 {
 452         int error = __acpi_pm_prepare();
 453         if (!error)
 454                 error = acpi_pm_pre_suspend();
 455
 456         return error;
 457 }
 458
 459 /**
 460  *      acpi_pm_finish - Instruct the platform to leave a sleep state.
 461  *
 462  *      This is called after we wake back up (or if entering the sleep state
 463  *      failed).
 464  */
 465 static void acpi_pm_finish(void)
 466 {
 467         struct acpi_device *pwr_btn_adev;
 468         u32 acpi_state = acpi_target_sleep_state;
 469
 470         acpi_ec_unblock_transactions();
 471         suspend_nvs_free();
 472
 473         if (acpi_state == ACPI_STATE_S0)
 474                 return;
 475
 476         printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
 477                 acpi_state);
 478         acpi_disable_wakeup_devices(acpi_state);
 479         acpi_leave_sleep_state(acpi_state);
 480
 481         /* reset firmware waking vector */
 482         acpi_set_waking_vector(0);
 483
 484         acpi_target_sleep_state = ACPI_STATE_S0;
 485
 486         acpi_resume_power_resources();
 487
 488         /* If we were woken with the fixed power button, provide a small
 489          * hint to userspace in the form of a wakeup event on the fixed power
 490          * button device (if it can be found).
 491          *
 492          * We delay the event generation til now, as the PM layer requires
 493          * timekeeping to be running before we generate events. */
 494         if (!pwr_btn_event_pending)
 495                 return;
 496
 497         pwr_btn_event_pending = false;
 498         pwr_btn_adev = acpi_dev_get_first_match_dev(ACPI_BUTTON_HID_POWERF,
 499                                                     NULL, -1);
 500         if (pwr_btn_adev) {
 501                 pm_wakeup_event(&pwr_btn_adev->dev, 0);
 502                 acpi_dev_put(pwr_btn_adev);
 503         }
 504 }
 505
 506 /**
 507  * acpi_pm_start - Start system PM transition.
 508  */
 509 static void acpi_pm_start(u32 acpi_state)
 510 {
 511         acpi_target_sleep_state = acpi_state;
 512         acpi_sleep_tts_switch(acpi_target_sleep_state);
 513         acpi_scan_lock_acquire();
 514 }
 515
 516 /**
 517  * acpi_pm_end - Finish up system PM transition.
 518  */
 519 static void acpi_pm_end(void)
 520 {
 521         acpi_turn_off_unused_power_resources();
 522         acpi_scan_lock_release();
 523         /*
 524          * This is necessary in case acpi_pm_finish() is not called during a
 525          * failing transition to a sleep state.
 526          */
 527         acpi_target_sleep_state = ACPI_STATE_S0;
 528         acpi_sleep_tts_switch(acpi_target_sleep_state);
 529 }
 530 #else /* !CONFIG_ACPI_SLEEP */
 531 #define sleep_no_lps0   (1)
 532 #define acpi_target_sleep_state ACPI_STATE_S0
 533 #define acpi_sleep_default_s3   (1)
 534 static inline void acpi_sleep_dmi_check(void) {}
 535 #endif /* CONFIG_ACPI_SLEEP */
 536
 537 #ifdef CONFIG_SUSPEND
 538 static u32 acpi_suspend_states[] = {
 539         [PM_SUSPEND_ON] = ACPI_STATE_S0,
 540         [PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
 541         [PM_SUSPEND_MEM] = ACPI_STATE_S3,
 542         [PM_SUSPEND_MAX] = ACPI_STATE_S5
 543 };
 544
 545 /**
 546  *      acpi_suspend_begin - Set the target system sleep state to the state
 547  *              associated with given @pm_state, if supported.
 548  */
 549 static int acpi_suspend_begin(suspend_state_t pm_state)
 550 {
 551         u32 acpi_state = acpi_suspend_states[pm_state];
 552         int error;
 553
 554         error = (nvs_nosave || nvs_nosave_s3) ? 0 : suspend_nvs_alloc();
 555         if (error)
 556                 return error;
 557
 558         if (!sleep_states[acpi_state]) {
 559                 pr_err("ACPI does not support sleep state S%u\n", acpi_state);
 560                 return -ENOSYS;
 561         }
 562         if (acpi_state > ACPI_STATE_S1)
 563                 pm_set_suspend_via_firmware();
 564
 565         acpi_pm_start(acpi_state);
 566         return 0;
 567 }
 568
 569 /**
 570  *      acpi_suspend_enter - Actually enter a sleep state.
 571  *      @pm_state: ignored
 572  *
 573  *      Flush caches and go to sleep. For STR we have to call arch-specific
 574  *      assembly, which in turn call acpi_enter_sleep_state().
 575  *      It's unfortunate, but it works. Please fix if you're feeling frisky.
 576  */
 577 static int acpi_suspend_enter(suspend_state_t pm_state)
 578 {
 579         acpi_status status = AE_OK;
 580         u32 acpi_state = acpi_target_sleep_state;
 581         int error;
 582
 583         ACPI_FLUSH_CPU_CACHE();
 584
 585         trace_suspend_resume(TPS("acpi_suspend"), acpi_state, true);
 586         switch (acpi_state) {
 587         case ACPI_STATE_S1:
 588                 barrier();
 589                 status = acpi_enter_sleep_state(acpi_state);
 590                 break;
 591
 592         case ACPI_STATE_S3:
 593                 if (!acpi_suspend_lowlevel)
 594                         return -ENOSYS;
 595                 error = acpi_suspend_lowlevel();
 596                 if (error)
 597                         return error;
 598                 pr_info(PREFIX "Low-level resume complete\n");
 599                 pm_set_resume_via_firmware();
 600                 break;
 601         }
 602         trace_suspend_resume(TPS("acpi_suspend"), acpi_state, false);
 603
 604         /* This violates the spec but is required for bug compatibility. */
 605         acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
 606
 607         /* Reprogram control registers */
 608         acpi_leave_sleep_state_prep(acpi_state);
 609
 610         /* ACPI 3.0 specs (P62) says that it's the responsibility
 611          * of the OSPM to clear the status bit [ implying that the
 612          * POWER_BUTTON event should not reach userspace ]
 613          *
 614          * However, we do generate a small hint for userspace in the form of
 615          * a wakeup event. We flag this condition for now and generate the
 616          * event later, as we're currently too early in resume to be able to
 617          * generate wakeup events.
 618          */
 619         if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3)) {
 620                 acpi_event_status pwr_btn_status = ACPI_EVENT_FLAG_DISABLED;
 621
 622                 acpi_get_event_status(ACPI_EVENT_POWER_BUTTON, &pwr_btn_status);
 623
 624                 if (pwr_btn_status & ACPI_EVENT_FLAG_STATUS_SET) {
 625                         acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
 626                         /* Flag for later */
 627                         pwr_btn_event_pending = true;
 628                 }
 629         }
 630
 631         /*
 632          * Disable and clear GPE status before interrupt is enabled. Some GPEs
 633          * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
 634          * acpi_leave_sleep_state will reenable specific GPEs later
 635          */
 636         acpi_disable_all_gpes();
 637         /* Allow EC transactions to happen. */
 638         acpi_ec_unblock_transactions();
 639
 640         suspend_nvs_restore();
 641
 642         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 643 }
 644
 645 static int acpi_suspend_state_valid(suspend_state_t pm_state)
 646 {
 647         u32 acpi_state;
 648
 649         switch (pm_state) {
 650         case PM_SUSPEND_ON:
 651         case PM_SUSPEND_STANDBY:
 652         case PM_SUSPEND_MEM:
 653                 acpi_state = acpi_suspend_states[pm_state];
 654
 655                 return sleep_states[acpi_state];
 656         default:
 657                 return 0;
 658         }
 659 }
 660
 661 static const struct platform_suspend_ops acpi_suspend_ops = {
 662         .valid = acpi_suspend_state_valid,
 663         .begin = acpi_suspend_begin,
 664         .prepare_late = acpi_pm_prepare,
 665         .enter = acpi_suspend_enter,
 666         .wake = acpi_pm_finish,
 667         .end = acpi_pm_end,
 668 };
 669
 670 /**
 671  *      acpi_suspend_begin_old - Set the target system sleep state to the
 672  *              state associated with given @pm_state, if supported, and
 673  *              execute the _PTS control method.  This function is used if the
 674  *              pre-ACPI 2.0 suspend ordering has been requested.
 675  */
 676 static int acpi_suspend_begin_old(suspend_state_t pm_state)
 677 {
 678         int error = acpi_suspend_begin(pm_state);
 679         if (!error)
 680                 error = __acpi_pm_prepare();
 681
 682         return error;
 683 }
 684
 685 /*
 686  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 687  * been requested.
 688  */
 689 static const struct platform_suspend_ops acpi_suspend_ops_old = {
 690         .valid = acpi_suspend_state_valid,
 691         .begin = acpi_suspend_begin_old,
 692         .prepare_late = acpi_pm_pre_suspend,
 693         .enter = acpi_suspend_enter,
 694         .wake = acpi_pm_finish,
 695         .end = acpi_pm_end,
 696         .recover = acpi_pm_finish,
 697 };
 698
 699 static bool s2idle_in_progress;
 700 static bool s2idle_wakeup;
 701
 702 /*
 703  * On platforms supporting the Low Power S0 Idle interface there is an ACPI
 704  * device object with the PNP0D80 compatible device ID (System Power Management
 705  * Controller) and a specific _DSM method under it.  That method, if present,
 706  * can be used to indicate to the platform that the OS is transitioning into a
 707  * low-power state in which certain types of activity are not desirable or that
 708  * it is leaving such a state, which allows the platform to adjust its operation
 709  * mode accordingly.
 710  */
 711 static const struct acpi_device_id lps0_device_ids[] = {
 712         {"PNP0D80", },
 713         {"", },
 714 };
 715
 716 #define ACPI_LPS0_DSM_UUID      "c4eb40a0-6cd2-11e2-bcfd-0800200c9a66"
 717
 718 #define ACPI_LPS0_GET_DEVICE_CONSTRAINTS        1
 719 #define ACPI_LPS0_SCREEN_OFF    3
 720 #define ACPI_LPS0_SCREEN_ON     4
 721 #define ACPI_LPS0_ENTRY         5
 722 #define ACPI_LPS0_EXIT          6
 723
 724 static acpi_handle lps0_device_handle;
 725 static guid_t lps0_dsm_guid;
 726 static char lps0_dsm_func_mask;
 727
 728 /* Device constraint entry structure */
 729 struct lpi_device_info {
 730         char *name;
 731         int enabled;
 732         union acpi_object *package;
 733 };
 734
 735 /* Constraint package structure */
 736 struct lpi_device_constraint {
 737         int uid;
 738         int min_dstate;
 739         int function_states;
 740 };
 741
 742 struct lpi_constraints {
 743         acpi_handle handle;
 744         int min_dstate;
 745 };
 746
 747 static struct lpi_constraints *lpi_constraints_table;
 748 static int lpi_constraints_table_size;
 749
 750 static void lpi_device_get_constraints(void)
 751 {
 752         union acpi_object *out_obj;
 753         int i;
 754
 755         out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
 756                                           1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
 757                                           NULL, ACPI_TYPE_PACKAGE);
 758
 759         acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
 760                           out_obj ? "successful" : "failed");
 761
 762         if (!out_obj)
 763                 return;
 764
 765         lpi_constraints_table = kcalloc(out_obj->package.count,
 766                                         sizeof(*lpi_constraints_table),
 767                                         GFP_KERNEL);
 768         if (!lpi_constraints_table)
 769                 goto free_acpi_buffer;
 770
 771         acpi_handle_debug(lps0_device_handle, "LPI: constraints list begin:\n");
 772
 773         for (i = 0; i < out_obj->package.count; i++) {
 774                 struct lpi_constraints *constraint;
 775                 acpi_status status;
 776                 union acpi_object *package = &out_obj->package.elements[i];
 777                 struct lpi_device_info info = { };
 778                 int package_count = 0, j;
 779
 780                 if (!package)
 781                         continue;
 782
 783                 for (j = 0; j < package->package.count; ++j) {
 784                         union acpi_object *element =
 785                                         &(package->package.elements[j]);
 786
 787                         switch (element->type) {
 788                         case ACPI_TYPE_INTEGER:
 789                                 info.enabled = element->integer.value;
 790                                 break;
 791                         case ACPI_TYPE_STRING:
 792                                 info.name = element->string.pointer;
 793                                 break;
 794                         case ACPI_TYPE_PACKAGE:
 795                                 package_count = element->package.count;
 796                                 info.package = element->package.elements;
 797                                 break;
 798                         }
 799                 }
 800
 801                 if (!info.enabled || !info.package || !info.name)
 802                         continue;
 803
 804                 constraint = &lpi_constraints_table[lpi_constraints_table_size];
 805
 806                 status = acpi_get_handle(NULL, info.name, &constraint->handle);
 807                 if (ACPI_FAILURE(status))
 808                         continue;
 809
 810                 acpi_handle_debug(lps0_device_handle,
 811                                   "index:%d Name:%s\n", i, info.name);
 812
 813                 constraint->min_dstate = -1;
 814
 815                 for (j = 0; j < package_count; ++j) {
 816                         union acpi_object *info_obj = &info.package[j];
 817                         union acpi_object *cnstr_pkg;
 818                         union acpi_object *obj;
 819                         struct lpi_device_constraint dev_info;
 820
 821                         switch (info_obj->type) {
 822                         case ACPI_TYPE_INTEGER:
 823                                 /* version */
 824                                 break;
 825                         case ACPI_TYPE_PACKAGE:
 826                                 if (info_obj->package.count < 2)
 827                                         break;
 828
 829                                 cnstr_pkg = info_obj->package.elements;
 830                                 obj = &cnstr_pkg[0];
 831                                 dev_info.uid = obj->integer.value;
 832                                 obj = &cnstr_pkg[1];
 833                                 dev_info.min_dstate = obj->integer.value;
 834
 835                                 acpi_handle_debug(lps0_device_handle,
 836                                         "uid:%d min_dstate:%s\n",
 837                                         dev_info.uid,
 838                                         acpi_power_state_string(dev_info.min_dstate));
 839
 840                                 constraint->min_dstate = dev_info.min_dstate;
 841                                 break;
 842                         }
 843                 }
 844
 845                 if (constraint->min_dstate < 0) {
 846                         acpi_handle_debug(lps0_device_handle,
 847                                           "Incomplete constraint defined\n");
 848                         continue;
 849                 }
 850
 851                 lpi_constraints_table_size++;
 852         }
 853
 854         acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
 855
 856 free_acpi_buffer:
 857         ACPI_FREE(out_obj);
 858 }
 859
 860 static void lpi_check_constraints(void)
 861 {
 862         int i;
 863
 864         for (i = 0; i < lpi_constraints_table_size; ++i) {
 865                 acpi_handle handle = lpi_constraints_table[i].handle;
 866                 struct acpi_device *adev;
 867
 868                 if (!handle || acpi_bus_get_device(handle, &adev))
 869                         continue;
 870
 871                 acpi_handle_debug(handle,
 872                         "LPI: required min power state:%s current power state:%s\n",
 873                         acpi_power_state_string(lpi_constraints_table[i].min_dstate),
 874                         acpi_power_state_string(adev->power.state));
 875
 876                 if (!adev->flags.power_manageable) {
 877                         acpi_handle_info(handle, "LPI: Device not power manageable\n");
 878                         lpi_constraints_table[i].handle = NULL;
 879                         continue;
 880                 }
 881
 882                 if (adev->power.state < lpi_constraints_table[i].min_dstate)
 883                         acpi_handle_info(handle,
 884                                 "LPI: Constraint not met; min power state:%s current power state:%s\n",
 885                                 acpi_power_state_string(lpi_constraints_table[i].min_dstate),
 886                                 acpi_power_state_string(adev->power.state));
 887         }
 888 }
 889
 890 static void acpi_sleep_run_lps0_dsm(unsigned int func)
 891 {
 892         union acpi_object *out_obj;
 893
 894         if (!(lps0_dsm_func_mask & (1 << func)))
 895                 return;
 896
 897         out_obj = acpi_evaluate_dsm(lps0_device_handle, &lps0_dsm_guid, 1, func, NULL);
 898         ACPI_FREE(out_obj);
 899
 900         acpi_handle_debug(lps0_device_handle, "_DSM function %u evaluation %s\n",
 901                           func, out_obj ? "successful" : "failed");
 902 }
 903
 904 static int lps0_device_attach(struct acpi_device *adev,
 905                               const struct acpi_device_id *not_used)
 906 {
 907         union acpi_object *out_obj;
 908
 909         if (lps0_device_handle)
 910                 return 0;
 911
 912         if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0))
 913                 return 0;
 914
 915         guid_parse(ACPI_LPS0_DSM_UUID, &lps0_dsm_guid);
 916         /* Check if the _DSM is present and as expected. */
 917         out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 1, 0, NULL);
 918         if (!out_obj || out_obj->type != ACPI_TYPE_BUFFER) {
 919                 acpi_handle_debug(adev->handle,
 920                                   "_DSM function 0 evaluation failed\n");
 921                 return 0;
 922         }
 923
 924         lps0_dsm_func_mask = *(char *)out_obj->buffer.pointer;
 925
 926         ACPI_FREE(out_obj);
 927
 928         acpi_handle_debug(adev->handle, "_DSM function mask: 0x%x\n",
 929                           lps0_dsm_func_mask);
 930
 931         lps0_device_handle = adev->handle;
 932
 933         lpi_device_get_constraints();
 934
 935         /*
 936          * Use suspend-to-idle by default if the default suspend mode was not
 937          * set from the command line.
 938          */
 939         if (mem_sleep_default > PM_SUSPEND_MEM && !acpi_sleep_default_s3)
 940                 mem_sleep_current = PM_SUSPEND_TO_IDLE;
 941
 942         return 0;
 943 }
 944
 945 static struct acpi_scan_handler lps0_handler = {
 946         .ids = lps0_device_ids,
 947         .attach = lps0_device_attach,
 948 };
 949
 950 static int acpi_s2idle_begin(void)
 951 {
 952         acpi_scan_lock_acquire();
 953         s2idle_in_progress = true;
 954         return 0;
 955 }
 956
 957 static int acpi_s2idle_prepare(void)
 958 {
 959         if (lps0_device_handle && !sleep_no_lps0) {
 960                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF);
 961                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_ENTRY);
 962         }
 963
 964         if (acpi_sci_irq_valid())
 965                 enable_irq_wake(acpi_sci_irq);
 966
 967         acpi_enable_wakeup_devices(ACPI_STATE_S0);
 968
 969         /* Change the configuration of GPEs to avoid spurious wakeup. */
 970         acpi_enable_all_wakeup_gpes();
 971         acpi_os_wait_events_complete();
 972
 973         s2idle_wakeup = true;
 974         return 0;
 975 }
 976
 977 static void acpi_s2idle_wake(void)
 978 {
 979         if (lps0_device_handle && !sleep_no_lps0 && pm_debug_messages_on)
 980                 lpi_check_constraints();
 981
 982         /*
 983          * If IRQD_WAKEUP_ARMED is set for the SCI at this point, the SCI has
 984          * not triggered while suspended, so bail out.
 985          */
 986         if (!acpi_sci_irq_valid() ||
 987             irqd_is_wakeup_armed(irq_get_irq_data(acpi_sci_irq)))
 988                 return;
 989
 990         /*
 991          * If there are EC events to process, the wakeup may be a spurious one
 992          * coming from the EC.
 993          */
 994         if (acpi_ec_dispatch_gpe()) {
 995                 /*
 996                  * Cancel the wakeup and process all pending events in case
 997                  * there are any wakeup ones in there.
 998                  *
 999                  * Note that if any non-EC GPEs are active at this point, the
1000                  * SCI will retrigger after the rearming below, so no events
1001                  * should be missed by canceling the wakeup here.
1002                  */
1003                 pm_system_cancel_wakeup();
1004                 /*
1005                  * The EC driver uses the system workqueue and an additional
1006                  * special one, so those need to be flushed too.
1007                  */
1008                 acpi_os_wait_events_complete(); /* synchronize EC GPE processing */
1009                 acpi_ec_flush_work();
1010                 acpi_os_wait_events_complete(); /* synchronize Notify handling */
1011         }
1012
1013         rearm_wake_irq(acpi_sci_irq);
1014 }
1015
1016 static void acpi_s2idle_restore(void)
1017 {
1018         s2idle_wakeup = false;
1019
1020         acpi_enable_all_runtime_gpes();
1021
1022         acpi_disable_wakeup_devices(ACPI_STATE_S0);
1023
1024         if (acpi_sci_irq_valid())
1025                 disable_irq_wake(acpi_sci_irq);
1026
1027         if (lps0_device_handle && !sleep_no_lps0) {
1028                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_EXIT);
1029                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON);
1030         }
1031 }
1032
1033 static void acpi_s2idle_end(void)
1034 {
1035         s2idle_in_progress = false;
1036         acpi_scan_lock_release();
1037 }
1038
1039 static const struct platform_s2idle_ops acpi_s2idle_ops = {
1040         .begin = acpi_s2idle_begin,
1041         .prepare = acpi_s2idle_prepare,
1042         .wake = acpi_s2idle_wake,
1043         .restore = acpi_s2idle_restore,
1044         .end = acpi_s2idle_end,
1045 };
1046
1047 static void acpi_sleep_suspend_setup(void)
1048 {
1049         int i;
1050
1051         for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++)
1052                 if (acpi_sleep_state_supported(i))
1053                         sleep_states[i] = 1;
1054
1055         suspend_set_ops(old_suspend_ordering ?
1056                 &acpi_suspend_ops_old : &acpi_suspend_ops);
1057
1058         acpi_scan_add_handler(&lps0_handler);
1059         s2idle_set_ops(&acpi_s2idle_ops);
1060 }
1061
1062 #else /* !CONFIG_SUSPEND */
1063 #define s2idle_in_progress      (false)
1064 #define s2idle_wakeup           (false)
1065 #define lps0_device_handle      (NULL)
1066 static inline void acpi_sleep_suspend_setup(void) {}
1067 #endif /* !CONFIG_SUSPEND */
1068
1069 bool acpi_s2idle_wakeup(void)
1070 {
1071         return s2idle_wakeup;
1072 }
1073
1074 bool acpi_sleep_no_ec_events(void)
1075 {
1076         return !s2idle_in_progress;
1077 }
1078
1079 #ifdef CONFIG_PM_SLEEP
1080 static u32 saved_bm_rld;
1081
1082 static int  acpi_save_bm_rld(void)
1083 {
1084         acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &saved_bm_rld);
1085         return 0;
1086 }
1087
1088 static void  acpi_restore_bm_rld(void)
1089 {
1090         u32 resumed_bm_rld = 0;
1091
1092         acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &resumed_bm_rld);
1093         if (resumed_bm_rld == saved_bm_rld)
1094                 return;
1095
1096         acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, saved_bm_rld);
1097 }
1098
1099 static struct syscore_ops acpi_sleep_syscore_ops = {
1100         .suspend = acpi_save_bm_rld,
1101         .resume = acpi_restore_bm_rld,
1102 };
1103
1104 static void acpi_sleep_syscore_init(void)
1105 {
1106         register_syscore_ops(&acpi_sleep_syscore_ops);
1107 }
1108 #else
1109 static inline void acpi_sleep_syscore_init(void) {}
1110 #endif /* CONFIG_PM_SLEEP */
1111
1112 #ifdef CONFIG_HIBERNATION
1113 static unsigned long s4_hardware_signature;
1114 static struct acpi_table_facs *facs;
1115 static bool nosigcheck;
1116
1117 void __init acpi_no_s4_hw_signature(void)
1118 {
1119         nosigcheck = true;
1120 }
1121
1122 static int acpi_hibernation_begin(pm_message_t stage)
1123 {
1124         if (!nvs_nosave) {
1125                 int error = suspend_nvs_alloc();
1126                 if (error)
1127                         return error;
1128         }
1129
1130         if (stage.event == PM_EVENT_HIBERNATE)
1131                 pm_set_suspend_via_firmware();
1132
1133         acpi_pm_start(ACPI_STATE_S4);
1134         return 0;
1135 }
1136
1137 static int acpi_hibernation_enter(void)
1138 {
1139         acpi_status status = AE_OK;
1140
1141         ACPI_FLUSH_CPU_CACHE();
1142
1143         /* This shouldn't return.  If it returns, we have a problem */
1144         status = acpi_enter_sleep_state(ACPI_STATE_S4);
1145         /* Reprogram control registers */
1146         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
1147
1148         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
1149 }
1150
1151 static void acpi_hibernation_leave(void)
1152 {
1153         pm_set_resume_via_firmware();
1154         /*
1155          * If ACPI is not enabled by the BIOS and the boot kernel, we need to
1156          * enable it here.
1157          */
1158         acpi_enable();
1159         /* Reprogram control registers */
1160         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
1161         /* Check the hardware signature */
1162         if (facs && s4_hardware_signature != facs->hardware_signature)
1163                 pr_crit("ACPI: Hardware changed while hibernated, success doubtful!\n");
1164         /* Restore the NVS memory area */
1165         suspend_nvs_restore();
1166         /* Allow EC transactions to happen. */
1167         acpi_ec_unblock_transactions();
1168 }
1169
1170 static void acpi_pm_thaw(void)
1171 {
1172         acpi_ec_unblock_transactions();
1173         acpi_enable_all_runtime_gpes();
1174 }
1175
1176 static const struct platform_hibernation_ops acpi_hibernation_ops = {
1177         .begin = acpi_hibernation_begin,
1178         .end = acpi_pm_end,
1179         .pre_snapshot = acpi_pm_prepare,
1180         .finish = acpi_pm_finish,
1181         .prepare = acpi_pm_prepare,
1182         .enter = acpi_hibernation_enter,
1183         .leave = acpi_hibernation_leave,
1184         .pre_restore = acpi_pm_freeze,
1185         .restore_cleanup = acpi_pm_thaw,
1186 };
1187
1188 /**
1189  *      acpi_hibernation_begin_old - Set the target system sleep state to
1190  *              ACPI_STATE_S4 and execute the _PTS control method.  This
1191  *              function is used if the pre-ACPI 2.0 suspend ordering has been
1192  *              requested.
1193  */
1194 static int acpi_hibernation_begin_old(pm_message_t stage)
1195 {
1196         int error;
1197         /*
1198          * The _TTS object should always be evaluated before the _PTS object.
1199          * When the old_suspended_ordering is true, the _PTS object is
1200          * evaluated in the acpi_sleep_prepare.
1201          */
1202         acpi_sleep_tts_switch(ACPI_STATE_S4);
1203
1204         error = acpi_sleep_prepare(ACPI_STATE_S4);
1205         if (error)
1206                 return error;
1207
1208         if (!nvs_nosave) {
1209                 error = suspend_nvs_alloc();
1210                 if (error)
1211                         return error;
1212         }
1213
1214         if (stage.event == PM_EVENT_HIBERNATE)
1215                 pm_set_suspend_via_firmware();
1216
1217         acpi_target_sleep_state = ACPI_STATE_S4;
1218         acpi_scan_lock_acquire();
1219         return 0;
1220 }
1221
1222 /*
1223  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
1224  * been requested.
1225  */
1226 static const struct platform_hibernation_ops acpi_hibernation_ops_old = {
1227         .begin = acpi_hibernation_begin_old,
1228         .end = acpi_pm_end,
1229         .pre_snapshot = acpi_pm_pre_suspend,
1230         .prepare = acpi_pm_freeze,
1231         .finish = acpi_pm_finish,
1232         .enter = acpi_hibernation_enter,
1233         .leave = acpi_hibernation_leave,
1234         .pre_restore = acpi_pm_freeze,
1235         .restore_cleanup = acpi_pm_thaw,
1236         .recover = acpi_pm_finish,
1237 };
1238
1239 static void acpi_sleep_hibernate_setup(void)
1240 {
1241         if (!acpi_sleep_state_supported(ACPI_STATE_S4))
1242                 return;
1243
1244         hibernation_set_ops(old_suspend_ordering ?
1245                         &acpi_hibernation_ops_old : &acpi_hibernation_ops);
1246         sleep_states[ACPI_STATE_S4] = 1;
1247         if (nosigcheck)
1248                 return;
1249
1250         acpi_get_table(ACPI_SIG_FACS, 1, (struct acpi_table_header **)&facs);
1251         if (facs)
1252                 s4_hardware_signature = facs->hardware_signature;
1253 }
1254 #else /* !CONFIG_HIBERNATION */
1255 static inline void acpi_sleep_hibernate_setup(void) {}
1256 #endif /* !CONFIG_HIBERNATION */
1257
1258 static void acpi_power_off_prepare(void)
1259 {
1260         /* Prepare to power off the system */
1261         acpi_sleep_prepare(ACPI_STATE_S5);
1262         acpi_disable_all_gpes();
1263         acpi_os_wait_events_complete();
1264 }
1265
1266 static void acpi_power_off(void)
1267 {
1268         /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
1269         printk(KERN_DEBUG "%s called\n", __func__);
1270         local_irq_disable();
1271         acpi_enter_sleep_state(ACPI_STATE_S5);
1272 }
1273
1274 int __init acpi_sleep_init(void)
1275 {
1276         char supported[ACPI_S_STATE_COUNT * 3 + 1];
1277         char *pos = supported;
1278         int i;
1279
1280         acpi_sleep_dmi_check();
1281
1282         sleep_states[ACPI_STATE_S0] = 1;
1283
1284         acpi_sleep_syscore_init();
1285         acpi_sleep_suspend_setup();
1286         acpi_sleep_hibernate_setup();
1287
1288         if (acpi_sleep_state_supported(ACPI_STATE_S5)) {
1289                 sleep_states[ACPI_STATE_S5] = 1;
1290                 pm_power_off_prepare = acpi_power_off_prepare;
1291                 pm_power_off = acpi_power_off;
1292         } else {
1293                 acpi_no_s5 = true;
1294         }
1295
1296         supported[0] = 0;
1297         for (i = 0; i < ACPI_S_STATE_COUNT; i++) {
1298                 if (sleep_states[i])
1299                         pos += sprintf(pos, " S%d", i);
1300         }
1301         pr_info(PREFIX "(supports%s)\n", supported);
1302
1303         /*
1304          * Register the tts_notifier to reboot notifier list so that the _TTS
1305          * object can also be evaluated when the system enters S5.
1306          */
1307         register_reboot_notifier(&tts_notifier);
1308         return 0;
1309 }