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 #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 /*
  85  * The ACPI specification wants us to save NVS memory regions during hibernation
  86  * and to restore them during the subsequent resume.  Windows does that also for
  87  * suspend to RAM.  However, it is known that this mechanism does not work on
  88  * all machines, so we allow the user to disable it with the help of the
  89  * 'acpi_sleep=nonvs' kernel command line option.
  90  */
  91 static bool nvs_nosave;
  92
  93 void __init acpi_nvs_nosave(void)
  94 {
  95         nvs_nosave = true;
  96 }
  97
  98 /*
  99  * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
 100  * user to request that behavior by using the 'acpi_old_suspend_ordering'
 101  * kernel command line option that causes the following variable to be set.
 102  */
 103 static bool old_suspend_ordering;
 104
 105 void __init acpi_old_suspend_ordering(void)
 106 {
 107         old_suspend_ordering = true;
 108 }
 109
 110 /**
 111  * acpi_pm_freeze - Disable the GPEs and suspend EC transactions.
 112  */
 113 static int acpi_pm_freeze(void)
 114 {
 115         acpi_disable_all_gpes();
 116         acpi_os_wait_events_complete(NULL);
 117         acpi_ec_block_transactions();
 118         return 0;
 119 }
 120
 121 /**
 122  * acpi_pre_suspend - Enable wakeup devices, "freeze" EC and save NVS.
 123  */
 124 static int acpi_pm_pre_suspend(void)
 125 {
 126         acpi_pm_freeze();
 127         suspend_nvs_save();
 128         return 0;
 129 }
 130
 131 /**
 132  *      __acpi_pm_prepare - Prepare the platform to enter the target state.
 133  *
 134  *      If necessary, set the firmware waking vector and do arch-specific
 135  *      nastiness to get the wakeup code to the waking vector.
 136  */
 137 static int __acpi_pm_prepare(void)
 138 {
 139         int error = acpi_sleep_prepare(acpi_target_sleep_state);
 140         if (error)
 141                 acpi_target_sleep_state = ACPI_STATE_S0;
 142
 143         return error;
 144 }
 145
 146 /**
 147  *      acpi_pm_prepare - Prepare the platform to enter the target sleep
 148  *              state and disable the GPEs.
 149  */
 150 static int acpi_pm_prepare(void)
 151 {
 152         int error = __acpi_pm_prepare();
 153         if (!error)
 154                 acpi_pm_pre_suspend();
 155
 156         return error;
 157 }
 158
 159 /**
 160  *      acpi_pm_finish - Instruct the platform to leave a sleep state.
 161  *
 162  *      This is called after we wake back up (or if entering the sleep state
 163  *      failed).
 164  */
 165 static void acpi_pm_finish(void)
 166 {
 167         u32 acpi_state = acpi_target_sleep_state;
 168
 169         acpi_ec_unblock_transactions();
 170
 171         if (acpi_state == ACPI_STATE_S0)
 172                 return;
 173
 174         printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
 175                 acpi_state);
 176         acpi_disable_wakeup_devices(acpi_state);
 177         acpi_leave_sleep_state(acpi_state);
 178
 179         /* reset firmware waking vector */
 180         acpi_set_firmware_waking_vector((acpi_physical_address) 0);
 181
 182         acpi_target_sleep_state = ACPI_STATE_S0;
 183 }
 184
 185 /**
 186  *      acpi_pm_end - Finish up suspend sequence.
 187  */
 188 static void acpi_pm_end(void)
 189 {
 190         suspend_nvs_free();
 191         /*
 192          * This is necessary in case acpi_pm_finish() is not called during a
 193          * failing transition to a sleep state.
 194          */
 195         acpi_target_sleep_state = ACPI_STATE_S0;
 196         acpi_sleep_tts_switch(acpi_target_sleep_state);
 197 }
 198 #else /* !CONFIG_ACPI_SLEEP */
 199 #define acpi_target_sleep_state ACPI_STATE_S0
 200 #endif /* CONFIG_ACPI_SLEEP */
 201
 202 #ifdef CONFIG_SUSPEND
 203 extern void do_suspend_lowlevel(void);
 204
 205 static u32 acpi_suspend_states[] = {
 206         [PM_SUSPEND_ON] = ACPI_STATE_S0,
 207         [PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
 208         [PM_SUSPEND_MEM] = ACPI_STATE_S3,
 209         [PM_SUSPEND_MAX] = ACPI_STATE_S5
 210 };
 211
 212 /**
 213  *      acpi_suspend_begin - Set the target system sleep state to the state
 214  *              associated with given @pm_state, if supported.
 215  */
 216 static int acpi_suspend_begin(suspend_state_t pm_state)
 217 {
 218         u32 acpi_state = acpi_suspend_states[pm_state];
 219         int error = 0;
 220
 221         error = nvs_nosave ? 0 : suspend_nvs_alloc();
 222         if (error)
 223                 return error;
 224
 225         if (sleep_states[acpi_state]) {
 226                 acpi_target_sleep_state = acpi_state;
 227                 acpi_sleep_tts_switch(acpi_target_sleep_state);
 228         } else {
 229                 printk(KERN_ERR "ACPI does not support this state: %d\n",
 230                         pm_state);
 231                 error = -ENOSYS;
 232         }
 233         return error;
 234 }
 235
 236 /**
 237  *      acpi_suspend_enter - Actually enter a sleep state.
 238  *      @pm_state: ignored
 239  *
 240  *      Flush caches and go to sleep. For STR we have to call arch-specific
 241  *      assembly, which in turn call acpi_enter_sleep_state().
 242  *      It's unfortunate, but it works. Please fix if you're feeling frisky.
 243  */
 244 static int acpi_suspend_enter(suspend_state_t pm_state)
 245 {
 246         acpi_status status = AE_OK;
 247         unsigned long flags = 0;
 248         u32 acpi_state = acpi_target_sleep_state;
 249
 250         ACPI_FLUSH_CPU_CACHE();
 251
 252         /* Do arch specific saving of state. */
 253         if (acpi_state == ACPI_STATE_S3) {
 254                 int error = acpi_save_state_mem();
 255
 256                 if (error)
 257                         return error;
 258         }
 259
 260         local_irq_save(flags);
 261         switch (acpi_state) {
 262         case ACPI_STATE_S1:
 263                 barrier();
 264                 status = acpi_enter_sleep_state(acpi_state);
 265                 break;
 266
 267         case ACPI_STATE_S3:
 268                 do_suspend_lowlevel();
 269                 break;
 270         }
 271
 272         /* This violates the spec but is required for bug compatibility. */
 273         acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
 274
 275         /* Reprogram control registers and execute _BFS */
 276         acpi_leave_sleep_state_prep(acpi_state);
 277
 278         /* ACPI 3.0 specs (P62) says that it's the responsibility
 279          * of the OSPM to clear the status bit [ implying that the
 280          * POWER_BUTTON event should not reach userspace ]
 281          */
 282         if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3))
 283                 acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
 284
 285         /*
 286          * Disable and clear GPE status before interrupt is enabled. Some GPEs
 287          * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
 288          * acpi_leave_sleep_state will reenable specific GPEs later
 289          */
 290         acpi_disable_all_gpes();
 291         /* Allow EC transactions to happen. */
 292         acpi_ec_unblock_transactions_early();
 293
 294         local_irq_restore(flags);
 295         printk(KERN_DEBUG "Back to C!\n");
 296
 297         /* restore processor state */
 298         if (acpi_state == ACPI_STATE_S3)
 299                 acpi_restore_state_mem();
 300
 301         suspend_nvs_restore();
 302
 303         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 304 }
 305
 306 static int acpi_suspend_state_valid(suspend_state_t pm_state)
 307 {
 308         u32 acpi_state;
 309
 310         switch (pm_state) {
 311         case PM_SUSPEND_ON:
 312         case PM_SUSPEND_STANDBY:
 313         case PM_SUSPEND_MEM:
 314                 acpi_state = acpi_suspend_states[pm_state];
 315
 316                 return sleep_states[acpi_state];
 317         default:
 318                 return 0;
 319         }
 320 }
 321
 322 static struct platform_suspend_ops acpi_suspend_ops = {
 323         .valid = acpi_suspend_state_valid,
 324         .begin = acpi_suspend_begin,
 325         .prepare_late = acpi_pm_prepare,
 326         .enter = acpi_suspend_enter,
 327         .wake = acpi_pm_finish,
 328         .end = acpi_pm_end,
 329 };
 330
 331 /**
 332  *      acpi_suspend_begin_old - Set the target system sleep state to the
 333  *              state associated with given @pm_state, if supported, and
 334  *              execute the _PTS control method.  This function is used if the
 335  *              pre-ACPI 2.0 suspend ordering has been requested.
 336  */
 337 static int acpi_suspend_begin_old(suspend_state_t pm_state)
 338 {
 339         int error = acpi_suspend_begin(pm_state);
 340         if (!error)
 341                 error = __acpi_pm_prepare();
 342
 343         return error;
 344 }
 345
 346 /*
 347  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 348  * been requested.
 349  */
 350 static struct platform_suspend_ops acpi_suspend_ops_old = {
 351         .valid = acpi_suspend_state_valid,
 352         .begin = acpi_suspend_begin_old,
 353         .prepare_late = acpi_pm_pre_suspend,
 354         .enter = acpi_suspend_enter,
 355         .wake = acpi_pm_finish,
 356         .end = acpi_pm_end,
 357         .recover = acpi_pm_finish,
 358 };
 359
 360 static int __init init_old_suspend_ordering(const struct dmi_system_id *d)
 361 {
 362         old_suspend_ordering = true;
 363         return 0;
 364 }
 365
 366 static int __init init_nvs_nosave(const struct dmi_system_id *d)
 367 {
 368         acpi_nvs_nosave();
 369         return 0;
 370 }
 371
 372 static struct dmi_system_id __initdata acpisleep_dmi_table[] = {
 373         {
 374         .callback = init_old_suspend_ordering,
 375         .ident = "Abit KN9 (nForce4 variant)",
 376         .matches = {
 377                 DMI_MATCH(DMI_BOARD_VENDOR, "http://www.abit.com.tw/"),
 378                 DMI_MATCH(DMI_BOARD_NAME, "KN9 Series(NF-CK804)"),
 379                 },
 380         },
 381         {
 382         .callback = init_old_suspend_ordering,
 383         .ident = "HP xw4600 Workstation",
 384         .matches = {
 385                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 386                 DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
 387                 },
 388         },
 389         {
 390         .callback = init_old_suspend_ordering,
 391         .ident = "Asus Pundit P1-AH2 (M2N8L motherboard)",
 392         .matches = {
 393                 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTek Computer INC."),
 394                 DMI_MATCH(DMI_BOARD_NAME, "M2N8L"),
 395                 },
 396         },
 397         {
 398         .callback = init_old_suspend_ordering,
 399         .ident = "Panasonic CF51-2L",
 400         .matches = {
 401                 DMI_MATCH(DMI_BOARD_VENDOR,
 402                                 "Matsushita Electric Industrial Co.,Ltd."),
 403                 DMI_MATCH(DMI_BOARD_NAME, "CF51-2L"),
 404                 },
 405         },
 406         {
 407         .callback = init_nvs_nosave,
 408         .ident = "Sony Vaio VGN-SR11M",
 409         .matches = {
 410                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 411                 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR11M"),
 412                 },
 413         },
 414         {
 415         .callback = init_nvs_nosave,
 416         .ident = "Everex StepNote Series",
 417         .matches = {
 418                 DMI_MATCH(DMI_SYS_VENDOR, "Everex Systems, Inc."),
 419                 DMI_MATCH(DMI_PRODUCT_NAME, "Everex StepNote Series"),
 420                 },
 421         },
 422         {},
 423 };
 424 #endif /* CONFIG_SUSPEND */
 425
 426 #ifdef CONFIG_HIBERNATION
 427 static unsigned long s4_hardware_signature;
 428 static struct acpi_table_facs *facs;
 429 static bool nosigcheck;
 430
 431 void __init acpi_no_s4_hw_signature(void)
 432 {
 433         nosigcheck = true;
 434 }
 435
 436 static int acpi_hibernation_begin(void)
 437 {
 438         int error;
 439
 440         error = nvs_nosave ? 0 : suspend_nvs_alloc();
 441         if (!error) {
 442                 acpi_target_sleep_state = ACPI_STATE_S4;
 443                 acpi_sleep_tts_switch(acpi_target_sleep_state);
 444         }
 445
 446         return error;
 447 }
 448
 449 static int acpi_hibernation_enter(void)
 450 {
 451         acpi_status status = AE_OK;
 452         unsigned long flags = 0;
 453
 454         ACPI_FLUSH_CPU_CACHE();
 455
 456         local_irq_save(flags);
 457         /* This shouldn't return.  If it returns, we have a problem */
 458         status = acpi_enter_sleep_state(ACPI_STATE_S4);
 459         /* Reprogram control registers and execute _BFS */
 460         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 461         local_irq_restore(flags);
 462
 463         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 464 }
 465
 466 static void acpi_hibernation_leave(void)
 467 {
 468         /*
 469          * If ACPI is not enabled by the BIOS and the boot kernel, we need to
 470          * enable it here.
 471          */
 472         acpi_enable();
 473         /* Reprogram control registers and execute _BFS */
 474         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 475         /* Check the hardware signature */
 476         if (facs && s4_hardware_signature != facs->hardware_signature) {
 477                 printk(KERN_EMERG "ACPI: Hardware changed while hibernated, "
 478                         "cannot resume!\n");
 479                 panic("ACPI S4 hardware signature mismatch");
 480         }
 481         /* Restore the NVS memory area */
 482         suspend_nvs_restore();
 483         /* Allow EC transactions to happen. */
 484         acpi_ec_unblock_transactions_early();
 485 }
 486
 487 static void acpi_pm_thaw(void)
 488 {
 489         acpi_ec_unblock_transactions();
 490         acpi_enable_all_runtime_gpes();
 491 }
 492
 493 static struct platform_hibernation_ops acpi_hibernation_ops = {
 494         .begin = acpi_hibernation_begin,
 495         .end = acpi_pm_end,
 496         .pre_snapshot = acpi_pm_prepare,
 497         .finish = acpi_pm_finish,
 498         .prepare = acpi_pm_prepare,
 499         .enter = acpi_hibernation_enter,
 500         .leave = acpi_hibernation_leave,
 501         .pre_restore = acpi_pm_freeze,
 502         .restore_cleanup = acpi_pm_thaw,
 503 };
 504
 505 /**
 506  *      acpi_hibernation_begin_old - Set the target system sleep state to
 507  *              ACPI_STATE_S4 and execute the _PTS control method.  This
 508  *              function is used if the pre-ACPI 2.0 suspend ordering has been
 509  *              requested.
 510  */
 511 static int acpi_hibernation_begin_old(void)
 512 {
 513         int error;
 514         /*
 515          * The _TTS object should always be evaluated before the _PTS object.
 516          * When the old_suspended_ordering is true, the _PTS object is
 517          * evaluated in the acpi_sleep_prepare.
 518          */
 519         acpi_sleep_tts_switch(ACPI_STATE_S4);
 520
 521         error = acpi_sleep_prepare(ACPI_STATE_S4);
 522
 523         if (!error) {
 524                 if (!nvs_nosave)
 525                         error = suspend_nvs_alloc();
 526                 if (!error)
 527                         acpi_target_sleep_state = ACPI_STATE_S4;
 528         }
 529         return error;
 530 }
 531
 532 /*
 533  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 534  * been requested.
 535  */
 536 static struct platform_hibernation_ops acpi_hibernation_ops_old = {
 537         .begin = acpi_hibernation_begin_old,
 538         .end = acpi_pm_end,
 539         .pre_snapshot = acpi_pm_pre_suspend,
 540         .prepare = acpi_pm_freeze,
 541         .finish = acpi_pm_finish,
 542         .enter = acpi_hibernation_enter,
 543         .leave = acpi_hibernation_leave,
 544         .pre_restore = acpi_pm_freeze,
 545         .restore_cleanup = acpi_pm_thaw,
 546         .recover = acpi_pm_finish,
 547 };
 548 #endif /* CONFIG_HIBERNATION */
 549
 550 int acpi_suspend(u32 acpi_state)
 551 {
 552         suspend_state_t states[] = {
 553                 [1] = PM_SUSPEND_STANDBY,
 554                 [3] = PM_SUSPEND_MEM,
 555                 [5] = PM_SUSPEND_MAX
 556         };
 557
 558         if (acpi_state < 6 && states[acpi_state])
 559                 return pm_suspend(states[acpi_state]);
 560         if (acpi_state == 4)
 561                 return hibernate();
 562         return -EINVAL;
 563 }
 564
 565 #ifdef CONFIG_PM_SLEEP
 566 /**
 567  *      acpi_pm_device_sleep_state - return preferred power state of ACPI device
 568  *              in the system sleep state given by %acpi_target_sleep_state
 569  *      @dev: device to examine; its driver model wakeup flags control
 570  *              whether it should be able to wake up the system
 571  *      @d_min_p: used to store the upper limit of allowed states range
 572  *      Return value: preferred power state of the device on success, -ENODEV on
 573  *              failure (ie. if there's no 'struct acpi_device' for @dev)
 574  *
 575  *      Find the lowest power (highest number) ACPI device power state that
 576  *      device @dev can be in while the system is in the sleep state represented
 577  *      by %acpi_target_sleep_state.  If @wake is nonzero, the device should be
 578  *      able to wake up the system from this sleep state.  If @d_min_p is set,
 579  *      the highest power (lowest number) device power state of @dev allowed
 580  *      in this system sleep state is stored at the location pointed to by it.
 581  *
 582  *      The caller must ensure that @dev is valid before using this function.
 583  *      The caller is also responsible for figuring out if the device is
 584  *      supposed to be able to wake up the system and passing this information
 585  *      via @wake.
 586  */
 587
 588 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p)
 589 {
 590         acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
 591         struct acpi_device *adev;
 592         char acpi_method[] = "_SxD";
 593         unsigned long long d_min, d_max;
 594
 595         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
 596                 printk(KERN_DEBUG "ACPI handle has no context!\n");
 597                 return -ENODEV;
 598         }
 599
 600         acpi_method[2] = '0' + acpi_target_sleep_state;
 601         /*
 602          * If the sleep state is S0, we will return D3, but if the device has
 603          * _S0W, we will use the value from _S0W
 604          */
 605         d_min = ACPI_STATE_D0;
 606         d_max = ACPI_STATE_D3;
 607
 608         /*
 609          * If present, _SxD methods return the minimum D-state (highest power
 610          * state) we can use for the corresponding S-states.  Otherwise, the
 611          * minimum D-state is D0 (ACPI 3.x).
 612          *
 613          * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
 614          * provided -- that's our fault recovery, we ignore retval.
 615          */
 616         if (acpi_target_sleep_state > ACPI_STATE_S0)
 617                 acpi_evaluate_integer(handle, acpi_method, NULL, &d_min);
 618
 619         /*
 620          * If _PRW says we can wake up the system from the target sleep state,
 621          * the D-state returned by _SxD is sufficient for that (we assume a
 622          * wakeup-aware driver if wake is set).  Still, if _SxW exists
 623          * (ACPI 3.x), it should return the maximum (lowest power) D-state that
 624          * can wake the system.  _S0W may be valid, too.
 625          */
 626         if (acpi_target_sleep_state == ACPI_STATE_S0 ||
 627             (device_may_wakeup(dev) && adev->wakeup.state.enabled &&
 628              adev->wakeup.sleep_state <= acpi_target_sleep_state)) {
 629                 acpi_status status;
 630
 631                 acpi_method[3] = 'W';
 632                 status = acpi_evaluate_integer(handle, acpi_method, NULL,
 633                                                 &d_max);
 634                 if (ACPI_FAILURE(status)) {
 635                         d_max = d_min;
 636                 } else if (d_max < d_min) {
 637                         /* Warn the user of the broken DSDT */
 638                         printk(KERN_WARNING "ACPI: Wrong value from %s\n",
 639                                 acpi_method);
 640                         /* Sanitize it */
 641                         d_min = d_max;
 642                 }
 643         }
 644
 645         if (d_min_p)
 646                 *d_min_p = d_min;
 647         return d_max;
 648 }
 649
 650 /**
 651  *      acpi_pm_device_sleep_wake - enable or disable the system wake-up
 652  *                                  capability of given device
 653  *      @dev: device to handle
 654  *      @enable: 'true' - enable, 'false' - disable the wake-up capability
 655  */
 656 int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
 657 {
 658         acpi_handle handle;
 659         struct acpi_device *adev;
 660         int error;
 661
 662         if (!device_can_wakeup(dev))
 663                 return -EINVAL;
 664
 665         handle = DEVICE_ACPI_HANDLE(dev);
 666         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
 667                 dev_dbg(dev, "ACPI handle has no context in %s!\n", __func__);
 668                 return -ENODEV;
 669         }
 670
 671         error = enable ?
 672                 acpi_enable_wakeup_device_power(adev, acpi_target_sleep_state) :
 673                 acpi_disable_wakeup_device_power(adev);
 674         if (!error)
 675                 dev_info(dev, "wake-up capability %s by ACPI\n",
 676                                 enable ? "enabled" : "disabled");
 677
 678         return error;
 679 }
 680 #endif
 681
 682 static void acpi_power_off_prepare(void)
 683 {
 684         /* Prepare to power off the system */
 685         acpi_sleep_prepare(ACPI_STATE_S5);
 686         acpi_disable_all_gpes();
 687 }
 688
 689 static void acpi_power_off(void)
 690 {
 691         /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
 692         printk(KERN_DEBUG "%s called\n", __func__);
 693         local_irq_disable();
 694         acpi_enter_sleep_state(ACPI_STATE_S5);
 695 }
 696
 697 /*
 698  * ACPI 2.0 created the optional _GTS and _BFS,
 699  * but industry adoption has been neither rapid nor broad.
 700  *
 701  * Linux gets into trouble when it executes poorly validated
 702  * paths through the BIOS, so disable _GTS and _BFS by default,
 703  * but do speak up and offer the option to enable them.
 704  */
 705 void __init acpi_gts_bfs_check(void)
 706 {
 707         acpi_handle dummy;
 708
 709         if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__GTS, &dummy)))
 710         {
 711                 printk(KERN_NOTICE PREFIX "BIOS offers _GTS\n");
 712                 printk(KERN_NOTICE PREFIX "If \"acpi.gts=1\" improves suspend, "
 713                         "please notify linux-acpi@vger.kernel.org\n");
 714         }
 715         if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__BFS, &dummy)))
 716         {
 717                 printk(KERN_NOTICE PREFIX "BIOS offers _BFS\n");
 718                 printk(KERN_NOTICE PREFIX "If \"acpi.bfs=1\" improves resume, "
 719                         "please notify linux-acpi@vger.kernel.org\n");
 720         }
 721 }
 722
 723 int __init acpi_sleep_init(void)
 724 {
 725         acpi_status status;
 726         u8 type_a, type_b;
 727 #ifdef CONFIG_SUSPEND
 728         int i = 0;
 729
 730         dmi_check_system(acpisleep_dmi_table);
 731 #endif
 732
 733         if (acpi_disabled)
 734                 return 0;
 735
 736         sleep_states[ACPI_STATE_S0] = 1;
 737         printk(KERN_INFO PREFIX "(supports S0");
 738
 739 #ifdef CONFIG_SUSPEND
 740         for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++) {
 741                 status = acpi_get_sleep_type_data(i, &type_a, &type_b);
 742                 if (ACPI_SUCCESS(status)) {
 743                         sleep_states[i] = 1;
 744                         printk(" S%d", i);
 745                 }
 746         }
 747
 748         suspend_set_ops(old_suspend_ordering ?
 749                 &acpi_suspend_ops_old : &acpi_suspend_ops);
 750 #endif
 751
 752 #ifdef CONFIG_HIBERNATION
 753         status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b);
 754         if (ACPI_SUCCESS(status)) {
 755                 hibernation_set_ops(old_suspend_ordering ?
 756                         &acpi_hibernation_ops_old : &acpi_hibernation_ops);
 757                 sleep_states[ACPI_STATE_S4] = 1;
 758                 printk(" S4");
 759                 if (!nosigcheck) {
 760                         acpi_get_table(ACPI_SIG_FACS, 1,
 761                                 (struct acpi_table_header **)&facs);
 762                         if (facs)
 763                                 s4_hardware_signature =
 764                                         facs->hardware_signature;
 765                 }
 766         }
 767 #endif
 768         status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
 769         if (ACPI_SUCCESS(status)) {
 770                 sleep_states[ACPI_STATE_S5] = 1;
 771                 printk(" S5");
 772                 pm_power_off_prepare = acpi_power_off_prepare;
 773                 pm_power_off = acpi_power_off;
 774         }
 775         printk(")\n");
 776         /*
 777          * Register the tts_notifier to reboot notifier list so that the _TTS
 778          * object can also be evaluated when the system enters S5.
 779          */
 780         register_reboot_notifier(&tts_notifier);
 781         acpi_gts_bfs_check();
 782         return 0;
 783 }