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
  20 #include <asm/io.h>
  21
  22 #include <acpi/acpi_bus.h>
  23 #include <acpi/acpi_drivers.h>
  24
  25 #include "internal.h"
  26 #include "sleep.h"
  27
  28 u8 sleep_states[ACPI_S_STATE_COUNT];
  29
  30 static void acpi_sleep_tts_switch(u32 acpi_state)
  31 {
  32         union acpi_object in_arg = { ACPI_TYPE_INTEGER };
  33         struct acpi_object_list arg_list = { 1, &in_arg };
  34         acpi_status status = AE_OK;
  35
  36         in_arg.integer.value = acpi_state;
  37         status = acpi_evaluate_object(NULL, "\\_TTS", &arg_list, NULL);
  38         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
  39                 /*
  40                  * OS can't evaluate the _TTS object correctly. Some warning
  41                  * message will be printed. But it won't break anything.
  42                  */
  43                 printk(KERN_NOTICE "Failure in evaluating _TTS object\n");
  44         }
  45 }
  46
  47 static int tts_notify_reboot(struct notifier_block *this,
  48                         unsigned long code, void *x)
  49 {
  50         acpi_sleep_tts_switch(ACPI_STATE_S5);
  51         return NOTIFY_DONE;
  52 }
  53
  54 static struct notifier_block tts_notifier = {
  55         .notifier_call  = tts_notify_reboot,
  56         .next           = NULL,
  57         .priority       = 0,
  58 };
  59
  60 static int acpi_sleep_prepare(u32 acpi_state)
  61 {
  62 #ifdef CONFIG_ACPI_SLEEP
  63         /* do we have a wakeup address for S2 and S3? */
  64         if (acpi_state == ACPI_STATE_S3) {
  65                 if (!acpi_wakeup_address) {
  66                         return -EFAULT;
  67                 }
  68                 acpi_set_firmware_waking_vector(
  69                                 (acpi_physical_address)acpi_wakeup_address);
  70
  71         }
  72         ACPI_FLUSH_CPU_CACHE();
  73         acpi_enable_wakeup_device_prep(acpi_state);
  74 #endif
  75         printk(KERN_INFO PREFIX "Preparing to enter system sleep state S%d\n",
  76                 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 /*
  85  * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
  86  * user to request that behavior by using the 'acpi_old_suspend_ordering'
  87  * kernel command line option that causes the following variable to be set.
  88  */
  89 static bool old_suspend_ordering;
  90
  91 void __init acpi_old_suspend_ordering(void)
  92 {
  93         old_suspend_ordering = true;
  94 }
  95
  96 /**
  97  * acpi_pm_freeze - Disable the GPEs and suspend EC transactions.
  98  */
  99 static int acpi_pm_freeze(void)
 100 {
 101         acpi_disable_all_gpes();
 102         acpi_os_wait_events_complete(NULL);
 103         acpi_ec_block_transactions();
 104         return 0;
 105 }
 106
 107 /**
 108  *      __acpi_pm_prepare - Prepare the platform to enter the target state.
 109  *
 110  *      If necessary, set the firmware waking vector and do arch-specific
 111  *      nastiness to get the wakeup code to the waking vector.
 112  */
 113 static int __acpi_pm_prepare(void)
 114 {
 115         int error = acpi_sleep_prepare(acpi_target_sleep_state);
 116
 117         if (error)
 118                 acpi_target_sleep_state = ACPI_STATE_S0;
 119         return error;
 120 }
 121
 122 /**
 123  *      acpi_pm_prepare - Prepare the platform to enter the target sleep
 124  *              state and disable the GPEs.
 125  */
 126 static int acpi_pm_prepare(void)
 127 {
 128         int error = __acpi_pm_prepare();
 129
 130         if (!error)
 131                 acpi_pm_freeze();
 132
 133         return error;
 134 }
 135
 136 /**
 137  *      acpi_pm_finish - Instruct the platform to leave a sleep state.
 138  *
 139  *      This is called after we wake back up (or if entering the sleep state
 140  *      failed).
 141  */
 142 static void acpi_pm_finish(void)
 143 {
 144         u32 acpi_state = acpi_target_sleep_state;
 145
 146         if (acpi_state == ACPI_STATE_S0)
 147                 return;
 148
 149         printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
 150                 acpi_state);
 151         acpi_disable_wakeup_device(acpi_state);
 152         acpi_leave_sleep_state(acpi_state);
 153
 154         /* reset firmware waking vector */
 155         acpi_set_firmware_waking_vector((acpi_physical_address) 0);
 156
 157         acpi_target_sleep_state = ACPI_STATE_S0;
 158 }
 159
 160 /**
 161  *      acpi_pm_end - Finish up suspend sequence.
 162  */
 163 static void acpi_pm_end(void)
 164 {
 165         /*
 166          * This is necessary in case acpi_pm_finish() is not called during a
 167          * failing transition to a sleep state.
 168          */
 169         acpi_target_sleep_state = ACPI_STATE_S0;
 170         acpi_sleep_tts_switch(acpi_target_sleep_state);
 171 }
 172 #else /* !CONFIG_ACPI_SLEEP */
 173 #define acpi_target_sleep_state ACPI_STATE_S0
 174 #endif /* CONFIG_ACPI_SLEEP */
 175
 176 #ifdef CONFIG_SUSPEND
 177 extern void do_suspend_lowlevel(void);
 178
 179 static u32 acpi_suspend_states[] = {
 180         [PM_SUSPEND_ON] = ACPI_STATE_S0,
 181         [PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
 182         [PM_SUSPEND_MEM] = ACPI_STATE_S3,
 183         [PM_SUSPEND_MAX] = ACPI_STATE_S5
 184 };
 185
 186 /**
 187  *      acpi_suspend_begin - Set the target system sleep state to the state
 188  *              associated with given @pm_state, if supported.
 189  */
 190 static int acpi_suspend_begin(suspend_state_t pm_state)
 191 {
 192         u32 acpi_state = acpi_suspend_states[pm_state];
 193         int error = 0;
 194
 195         if (sleep_states[acpi_state]) {
 196                 acpi_target_sleep_state = acpi_state;
 197                 acpi_sleep_tts_switch(acpi_target_sleep_state);
 198         } else {
 199                 printk(KERN_ERR "ACPI does not support this state: %d\n",
 200                         pm_state);
 201                 error = -ENOSYS;
 202         }
 203         return error;
 204 }
 205
 206 /**
 207  *      acpi_suspend_enter - Actually enter a sleep state.
 208  *      @pm_state: ignored
 209  *
 210  *      Flush caches and go to sleep. For STR we have to call arch-specific
 211  *      assembly, which in turn call acpi_enter_sleep_state().
 212  *      It's unfortunate, but it works. Please fix if you're feeling frisky.
 213  */
 214 static int acpi_suspend_enter(suspend_state_t pm_state)
 215 {
 216         acpi_status status = AE_OK;
 217         unsigned long flags = 0;
 218         u32 acpi_state = acpi_target_sleep_state;
 219
 220         ACPI_FLUSH_CPU_CACHE();
 221
 222         /* Do arch specific saving of state. */
 223         if (acpi_state == ACPI_STATE_S3) {
 224                 int error = acpi_save_state_mem();
 225
 226                 if (error)
 227                         return error;
 228         }
 229
 230         local_irq_save(flags);
 231         acpi_enable_wakeup_device(acpi_state);
 232         switch (acpi_state) {
 233         case ACPI_STATE_S1:
 234                 barrier();
 235                 status = acpi_enter_sleep_state(acpi_state);
 236                 break;
 237
 238         case ACPI_STATE_S3:
 239                 do_suspend_lowlevel();
 240                 break;
 241         }
 242
 243         /* This violates the spec but is required for bug compatibility. */
 244         acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
 245
 246         /* Reprogram control registers and execute _BFS */
 247         acpi_leave_sleep_state_prep(acpi_state);
 248
 249         /* ACPI 3.0 specs (P62) says that it's the responsibility
 250          * of the OSPM to clear the status bit [ implying that the
 251          * POWER_BUTTON event should not reach userspace ]
 252          */
 253         if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3))
 254                 acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
 255
 256         /*
 257          * Disable and clear GPE status before interrupt is enabled. Some GPEs
 258          * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
 259          * acpi_leave_sleep_state will reenable specific GPEs later
 260          */
 261         acpi_disable_all_gpes();
 262         /* Allow EC transactions to happen. */
 263         acpi_ec_unblock_transactions_early();
 264
 265         local_irq_restore(flags);
 266         printk(KERN_DEBUG "Back to C!\n");
 267
 268         /* restore processor state */
 269         if (acpi_state == ACPI_STATE_S3)
 270                 acpi_restore_state_mem();
 271
 272         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 273 }
 274
 275 static void acpi_suspend_finish(void)
 276 {
 277         acpi_ec_unblock_transactions();
 278         acpi_pm_finish();
 279 }
 280
 281 static int acpi_suspend_state_valid(suspend_state_t pm_state)
 282 {
 283         u32 acpi_state;
 284
 285         switch (pm_state) {
 286         case PM_SUSPEND_ON:
 287         case PM_SUSPEND_STANDBY:
 288         case PM_SUSPEND_MEM:
 289                 acpi_state = acpi_suspend_states[pm_state];
 290
 291                 return sleep_states[acpi_state];
 292         default:
 293                 return 0;
 294         }
 295 }
 296
 297 static struct platform_suspend_ops acpi_suspend_ops = {
 298         .valid = acpi_suspend_state_valid,
 299         .begin = acpi_suspend_begin,
 300         .prepare_late = acpi_pm_prepare,
 301         .enter = acpi_suspend_enter,
 302         .wake = acpi_suspend_finish,
 303         .end = acpi_pm_end,
 304 };
 305
 306 /**
 307  *      acpi_suspend_begin_old - Set the target system sleep state to the
 308  *              state associated with given @pm_state, if supported, and
 309  *              execute the _PTS control method.  This function is used if the
 310  *              pre-ACPI 2.0 suspend ordering has been requested.
 311  */
 312 static int acpi_suspend_begin_old(suspend_state_t pm_state)
 313 {
 314         int error = acpi_suspend_begin(pm_state);
 315
 316         if (!error)
 317                 error = __acpi_pm_prepare();
 318         return error;
 319 }
 320
 321 /*
 322  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 323  * been requested.
 324  */
 325 static struct platform_suspend_ops acpi_suspend_ops_old = {
 326         .valid = acpi_suspend_state_valid,
 327         .begin = acpi_suspend_begin_old,
 328         .prepare_late = acpi_pm_freeze,
 329         .enter = acpi_suspend_enter,
 330         .wake = acpi_suspend_finish,
 331         .end = acpi_pm_end,
 332         .recover = acpi_pm_finish,
 333 };
 334
 335 static int __init init_old_suspend_ordering(const struct dmi_system_id *d)
 336 {
 337         old_suspend_ordering = true;
 338         return 0;
 339 }
 340
 341 static struct dmi_system_id __initdata acpisleep_dmi_table[] = {
 342         {
 343         .callback = init_old_suspend_ordering,
 344         .ident = "Abit KN9 (nForce4 variant)",
 345         .matches = {
 346                 DMI_MATCH(DMI_BOARD_VENDOR, "http://www.abit.com.tw/"),
 347                 DMI_MATCH(DMI_BOARD_NAME, "KN9 Series(NF-CK804)"),
 348                 },
 349         },
 350         {
 351         .callback = init_old_suspend_ordering,
 352         .ident = "HP xw4600 Workstation",
 353         .matches = {
 354                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 355                 DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
 356                 },
 357         },
 358         {
 359         .callback = init_old_suspend_ordering,
 360         .ident = "Asus Pundit P1-AH2 (M2N8L motherboard)",
 361         .matches = {
 362                 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTek Computer INC."),
 363                 DMI_MATCH(DMI_BOARD_NAME, "M2N8L"),
 364                 },
 365         },
 366         {
 367         .callback = init_old_suspend_ordering,
 368         .ident = "Panasonic CF51-2L",
 369         .matches = {
 370                 DMI_MATCH(DMI_BOARD_VENDOR,
 371                                 "Matsushita Electric Industrial Co.,Ltd."),
 372                 DMI_MATCH(DMI_BOARD_NAME, "CF51-2L"),
 373                 },
 374         },
 375         {},
 376 };
 377 #endif /* CONFIG_SUSPEND */
 378
 379 #ifdef CONFIG_HIBERNATION
 380 /*
 381  * The ACPI specification wants us to save NVS memory regions during hibernation
 382  * and to restore them during the subsequent resume.  However, it is not certain
 383  * if this mechanism is going to work on all machines, so we allow the user to
 384  * disable this mechanism using the 'acpi_sleep=s4_nonvs' kernel command line
 385  * option.
 386  */
 387 static bool s4_no_nvs;
 388
 389 void __init acpi_s4_no_nvs(void)
 390 {
 391         s4_no_nvs = true;
 392 }
 393
 394 static unsigned long s4_hardware_signature;
 395 static struct acpi_table_facs *facs;
 396 static bool nosigcheck;
 397
 398 void __init acpi_no_s4_hw_signature(void)
 399 {
 400         nosigcheck = true;
 401 }
 402
 403 static int acpi_hibernation_begin(void)
 404 {
 405         int error;
 406
 407         error = s4_no_nvs ? 0 : hibernate_nvs_alloc();
 408         if (!error) {
 409                 acpi_target_sleep_state = ACPI_STATE_S4;
 410                 acpi_sleep_tts_switch(acpi_target_sleep_state);
 411         }
 412
 413         return error;
 414 }
 415
 416 static int acpi_hibernation_pre_snapshot(void)
 417 {
 418         int error = acpi_pm_prepare();
 419
 420         if (!error)
 421                 hibernate_nvs_save();
 422
 423         return error;
 424 }
 425
 426 static int acpi_hibernation_enter(void)
 427 {
 428         acpi_status status = AE_OK;
 429         unsigned long flags = 0;
 430
 431         ACPI_FLUSH_CPU_CACHE();
 432
 433         local_irq_save(flags);
 434         acpi_enable_wakeup_device(ACPI_STATE_S4);
 435         /* This shouldn't return.  If it returns, we have a problem */
 436         status = acpi_enter_sleep_state(ACPI_STATE_S4);
 437         /* Reprogram control registers and execute _BFS */
 438         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 439         local_irq_restore(flags);
 440
 441         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 442 }
 443
 444 static void acpi_hibernation_finish(void)
 445 {
 446         hibernate_nvs_free();
 447         acpi_ec_unblock_transactions();
 448         acpi_pm_finish();
 449 }
 450
 451 static void acpi_hibernation_leave(void)
 452 {
 453         /*
 454          * If ACPI is not enabled by the BIOS and the boot kernel, we need to
 455          * enable it here.
 456          */
 457         acpi_enable();
 458         /* Reprogram control registers and execute _BFS */
 459         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 460         /* Check the hardware signature */
 461         if (facs && s4_hardware_signature != facs->hardware_signature) {
 462                 printk(KERN_EMERG "ACPI: Hardware changed while hibernated, "
 463                         "cannot resume!\n");
 464                 panic("ACPI S4 hardware signature mismatch");
 465         }
 466         /* Restore the NVS memory area */
 467         hibernate_nvs_restore();
 468         /* Allow EC transactions to happen. */
 469         acpi_ec_unblock_transactions_early();
 470 }
 471
 472 static void acpi_pm_thaw(void)
 473 {
 474         acpi_ec_unblock_transactions();
 475         acpi_enable_all_runtime_gpes();
 476 }
 477
 478 static struct platform_hibernation_ops acpi_hibernation_ops = {
 479         .begin = acpi_hibernation_begin,
 480         .end = acpi_pm_end,
 481         .pre_snapshot = acpi_hibernation_pre_snapshot,
 482         .finish = acpi_hibernation_finish,
 483         .prepare = acpi_pm_prepare,
 484         .enter = acpi_hibernation_enter,
 485         .leave = acpi_hibernation_leave,
 486         .pre_restore = acpi_pm_freeze,
 487         .restore_cleanup = acpi_pm_thaw,
 488 };
 489
 490 /**
 491  *      acpi_hibernation_begin_old - Set the target system sleep state to
 492  *              ACPI_STATE_S4 and execute the _PTS control method.  This
 493  *              function is used if the pre-ACPI 2.0 suspend ordering has been
 494  *              requested.
 495  */
 496 static int acpi_hibernation_begin_old(void)
 497 {
 498         int error;
 499         /*
 500          * The _TTS object should always be evaluated before the _PTS object.
 501          * When the old_suspended_ordering is true, the _PTS object is
 502          * evaluated in the acpi_sleep_prepare.
 503          */
 504         acpi_sleep_tts_switch(ACPI_STATE_S4);
 505
 506         error = acpi_sleep_prepare(ACPI_STATE_S4);
 507
 508         if (!error) {
 509                 if (!s4_no_nvs)
 510                         error = hibernate_nvs_alloc();
 511                 if (!error)
 512                         acpi_target_sleep_state = ACPI_STATE_S4;
 513         }
 514         return error;
 515 }
 516
 517 static int acpi_hibernation_pre_snapshot_old(void)
 518 {
 519         acpi_pm_freeze();
 520         hibernate_nvs_save();
 521         return 0;
 522 }
 523
 524 /*
 525  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 526  * been requested.
 527  */
 528 static struct platform_hibernation_ops acpi_hibernation_ops_old = {
 529         .begin = acpi_hibernation_begin_old,
 530         .end = acpi_pm_end,
 531         .pre_snapshot = acpi_hibernation_pre_snapshot_old,
 532         .finish = acpi_hibernation_finish,
 533         .prepare = acpi_pm_freeze,
 534         .enter = acpi_hibernation_enter,
 535         .leave = acpi_hibernation_leave,
 536         .pre_restore = acpi_pm_freeze,
 537         .restore_cleanup = acpi_pm_thaw,
 538         .recover = acpi_pm_finish,
 539 };
 540 #endif /* CONFIG_HIBERNATION */
 541
 542 int acpi_suspend(u32 acpi_state)
 543 {
 544         suspend_state_t states[] = {
 545                 [1] = PM_SUSPEND_STANDBY,
 546                 [3] = PM_SUSPEND_MEM,
 547                 [5] = PM_SUSPEND_MAX
 548         };
 549
 550         if (acpi_state < 6 && states[acpi_state])
 551                 return pm_suspend(states[acpi_state]);
 552         if (acpi_state == 4)
 553                 return hibernate();
 554         return -EINVAL;
 555 }
 556
 557 #ifdef CONFIG_PM_SLEEP
 558 /**
 559  *      acpi_pm_device_sleep_state - return preferred power state of ACPI device
 560  *              in the system sleep state given by %acpi_target_sleep_state
 561  *      @dev: device to examine; its driver model wakeup flags control
 562  *              whether it should be able to wake up the system
 563  *      @d_min_p: used to store the upper limit of allowed states range
 564  *      Return value: preferred power state of the device on success, -ENODEV on
 565  *              failure (ie. if there's no 'struct acpi_device' for @dev)
 566  *
 567  *      Find the lowest power (highest number) ACPI device power state that
 568  *      device @dev can be in while the system is in the sleep state represented
 569  *      by %acpi_target_sleep_state.  If @wake is nonzero, the device should be
 570  *      able to wake up the system from this sleep state.  If @d_min_p is set,
 571  *      the highest power (lowest number) device power state of @dev allowed
 572  *      in this system sleep state is stored at the location pointed to by it.
 573  *
 574  *      The caller must ensure that @dev is valid before using this function.
 575  *      The caller is also responsible for figuring out if the device is
 576  *      supposed to be able to wake up the system and passing this information
 577  *      via @wake.
 578  */
 579
 580 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p)
 581 {
 582         acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
 583         struct acpi_device *adev;
 584         char acpi_method[] = "_SxD";
 585         unsigned long long d_min, d_max;
 586
 587         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
 588                 printk(KERN_DEBUG "ACPI handle has no context!\n");
 589                 return -ENODEV;
 590         }
 591
 592         acpi_method[2] = '0' + acpi_target_sleep_state;
 593         /*
 594          * If the sleep state is S0, we will return D3, but if the device has
 595          * _S0W, we will use the value from _S0W
 596          */
 597         d_min = ACPI_STATE_D0;
 598         d_max = ACPI_STATE_D3;
 599
 600         /*
 601          * If present, _SxD methods return the minimum D-state (highest power
 602          * state) we can use for the corresponding S-states.  Otherwise, the
 603          * minimum D-state is D0 (ACPI 3.x).
 604          *
 605          * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
 606          * provided -- that's our fault recovery, we ignore retval.
 607          */
 608         if (acpi_target_sleep_state > ACPI_STATE_S0)
 609                 acpi_evaluate_integer(handle, acpi_method, NULL, &d_min);
 610
 611         /*
 612          * If _PRW says we can wake up the system from the target sleep state,
 613          * the D-state returned by _SxD is sufficient for that (we assume a
 614          * wakeup-aware driver if wake is set).  Still, if _SxW exists
 615          * (ACPI 3.x), it should return the maximum (lowest power) D-state that
 616          * can wake the system.  _S0W may be valid, too.
 617          */
 618         if (acpi_target_sleep_state == ACPI_STATE_S0 ||
 619             (device_may_wakeup(dev) && adev->wakeup.state.enabled &&
 620              adev->wakeup.sleep_state <= acpi_target_sleep_state)) {
 621                 acpi_status status;
 622
 623                 acpi_method[3] = 'W';
 624                 status = acpi_evaluate_integer(handle, acpi_method, NULL,
 625                                                 &d_max);
 626                 if (ACPI_FAILURE(status)) {
 627                         d_max = d_min;
 628                 } else if (d_max < d_min) {
 629                         /* Warn the user of the broken DSDT */
 630                         printk(KERN_WARNING "ACPI: Wrong value from %s\n",
 631                                 acpi_method);
 632                         /* Sanitize it */
 633                         d_min = d_max;
 634                 }
 635         }
 636
 637         if (d_min_p)
 638                 *d_min_p = d_min;
 639         return d_max;
 640 }
 641
 642 /**
 643  *      acpi_pm_device_sleep_wake - enable or disable the system wake-up
 644  *                                  capability of given device
 645  *      @dev: device to handle
 646  *      @enable: 'true' - enable, 'false' - disable the wake-up capability
 647  */
 648 int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
 649 {
 650         acpi_handle handle;
 651         struct acpi_device *adev;
 652         int error;
 653
 654         if (!device_can_wakeup(dev))
 655                 return -EINVAL;
 656
 657         handle = DEVICE_ACPI_HANDLE(dev);
 658         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
 659                 dev_dbg(dev, "ACPI handle has no context in %s!\n", __func__);
 660                 return -ENODEV;
 661         }
 662
 663         if (enable) {
 664                 error = acpi_enable_wakeup_device_power(adev,
 665                                                 acpi_target_sleep_state);
 666                 if (!error)
 667                         acpi_enable_gpe(adev->wakeup.gpe_device,
 668                                         adev->wakeup.gpe_number,
 669                                         ACPI_GPE_TYPE_WAKE);
 670         } else {
 671                 acpi_disable_gpe(adev->wakeup.gpe_device, adev->wakeup.gpe_number,
 672                                 ACPI_GPE_TYPE_WAKE);
 673                 error = acpi_disable_wakeup_device_power(adev);
 674         }
 675         if (!error)
 676                 dev_info(dev, "wake-up capability %s by ACPI\n",
 677                                 enable ? "enabled" : "disabled");
 678
 679         return error;
 680 }
 681 #endif
 682
 683 static void acpi_power_off_prepare(void)
 684 {
 685         /* Prepare to power off the system */
 686         acpi_sleep_prepare(ACPI_STATE_S5);
 687         acpi_disable_all_gpes();
 688 }
 689
 690 static void acpi_power_off(void)
 691 {
 692         /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
 693         printk(KERN_DEBUG "%s called\n", __func__);
 694         local_irq_disable();
 695         acpi_enable_wakeup_device(ACPI_STATE_S5);
 696         acpi_enter_sleep_state(ACPI_STATE_S5);
 697 }
 698
 699 /*
 700  * ACPI 2.0 created the optional _GTS and _BFS,
 701  * but industry adoption has been neither rapid nor broad.
 702  *
 703  * Linux gets into trouble when it executes poorly validated
 704  * paths through the BIOS, so disable _GTS and _BFS by default,
 705  * but do speak up and offer the option to enable them.
 706  */
 707 void __init acpi_gts_bfs_check(void)
 708 {
 709         acpi_handle dummy;
 710
 711         if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__GTS, &dummy)))
 712         {
 713                 printk(KERN_NOTICE PREFIX "BIOS offers _GTS\n");
 714                 printk(KERN_NOTICE PREFIX "If \"acpi.gts=1\" improves suspend, "
 715                         "please notify linux-acpi@vger.kernel.org\n");
 716         }
 717         if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__BFS, &dummy)))
 718         {
 719                 printk(KERN_NOTICE PREFIX "BIOS offers _BFS\n");
 720                 printk(KERN_NOTICE PREFIX "If \"acpi.bfs=1\" improves resume, "
 721                         "please notify linux-acpi@vger.kernel.org\n");
 722         }
 723 }
 724
 725 int __init acpi_sleep_init(void)
 726 {
 727         acpi_status status;
 728         u8 type_a, type_b;
 729 #ifdef CONFIG_SUSPEND
 730         int i = 0;
 731
 732         dmi_check_system(acpisleep_dmi_table);
 733 #endif
 734
 735         if (acpi_disabled)
 736                 return 0;
 737
 738         sleep_states[ACPI_STATE_S0] = 1;
 739         printk(KERN_INFO PREFIX "(supports S0");
 740
 741 #ifdef CONFIG_SUSPEND
 742         for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++) {
 743                 status = acpi_get_sleep_type_data(i, &type_a, &type_b);
 744                 if (ACPI_SUCCESS(status)) {
 745                         sleep_states[i] = 1;
 746                         printk(" S%d", i);
 747                 }
 748         }
 749
 750         suspend_set_ops(old_suspend_ordering ?
 751                 &acpi_suspend_ops_old : &acpi_suspend_ops);
 752 #endif
 753
 754 #ifdef CONFIG_HIBERNATION
 755         status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b);
 756         if (ACPI_SUCCESS(status)) {
 757                 hibernation_set_ops(old_suspend_ordering ?
 758                         &acpi_hibernation_ops_old : &acpi_hibernation_ops);
 759                 sleep_states[ACPI_STATE_S4] = 1;
 760                 printk(" S4");
 761                 if (!nosigcheck) {
 762                         acpi_get_table(ACPI_SIG_FACS, 1,
 763                                 (struct acpi_table_header **)&facs);
 764                         if (facs)
 765                                 s4_hardware_signature =
 766                                         facs->hardware_signature;
 767                 }
 768         }
 769 #endif
 770         status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
 771         if (ACPI_SUCCESS(status)) {
 772                 sleep_states[ACPI_STATE_S5] = 1;
 773                 printk(" S5");
 774                 pm_power_off_prepare = acpi_power_off_prepare;
 775                 pm_power_off = acpi_power_off;
 776         }
 777         printk(")\n");
 778         /*
 779          * Register the tts_notifier to reboot notifier list so that the _TTS
 780          * object can also be evaluated when the system enters S5.
 781          */
 782         register_reboot_notifier(&tts_notifier);
 783         acpi_gts_bfs_check();
 784         return 0;
 785 }