Pileus Git - ~andy/linux/blob - drivers/acpi/sleep.c

   1 /*
   2  * sleep.c - ACPI sleep support.
   3  *
   4  * Copyright (c) 2005 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
   5  * Copyright (c) 2004 David Shaohua Li <shaohua.li@intel.com>
   6  * Copyright (c) 2000-2003 Patrick Mochel
   7  * Copyright (c) 2003 Open Source Development Lab
   8  *
   9  * This file is released under the GPLv2.
  10  *
  11  */
  12
  13 #include <linux/delay.h>
  14 #include <linux/irq.h>
  15 #include <linux/dmi.h>
  16 #include <linux/device.h>
  17 #include <linux/suspend.h>
  18 #include <linux/reboot.h>
  19 #include <linux/acpi.h>
  20
  21 #include <asm/io.h>
  22
  23 #include <acpi/acpi_bus.h>
  24 #include <acpi/acpi_drivers.h>
  25
  26 #include "internal.h"
  27 #include "sleep.h"
  28
  29 static u8 sleep_states[ACPI_S_STATE_COUNT];
  30
  31 static void acpi_sleep_tts_switch(u32 acpi_state)
  32 {
  33         union acpi_object in_arg = { ACPI_TYPE_INTEGER };
  34         struct acpi_object_list arg_list = { 1, &in_arg };
  35         acpi_status status = AE_OK;
  36
  37         in_arg.integer.value = acpi_state;
  38         status = acpi_evaluate_object(NULL, "\\_TTS", &arg_list, NULL);
  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                 }
  69                 acpi_set_firmware_waking_vector(
  70                                 (acpi_physical_address)acpi_wakeup_address);
  71
  72         }
  73         ACPI_FLUSH_CPU_CACHE();
  74 #endif
  75         printk(KERN_INFO PREFIX "Preparing to enter system sleep state S%d\n",
  76                 acpi_state);
  77         acpi_enable_wakeup_devices(acpi_state);
  78         acpi_enter_sleep_state_prep(acpi_state);
  79         return 0;
  80 }
  81
  82 #ifdef CONFIG_ACPI_SLEEP
  83 static u32 acpi_target_sleep_state = ACPI_STATE_S0;
  84
  85 /*
  86  * The ACPI specification wants us to save NVS memory regions during hibernation
  87  * and to restore them during the subsequent resume.  Windows does that also for
  88  * suspend to RAM.  However, it is known that this mechanism does not work on
  89  * all machines, so we allow the user to disable it with the help of the
  90  * 'acpi_sleep=nonvs' kernel command line option.
  91  */
  92 static bool nvs_nosave;
  93
  94 void __init acpi_nvs_nosave(void)
  95 {
  96         nvs_nosave = true;
  97 }
  98
  99 /*
 100  * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
 101  * user to request that behavior by using the 'acpi_old_suspend_ordering'
 102  * kernel command line option that causes the following variable to be set.
 103  */
 104 static bool old_suspend_ordering;
 105
 106 void __init acpi_old_suspend_ordering(void)
 107 {
 108         old_suspend_ordering = true;
 109 }
 110
 111 /**
 112  * acpi_pm_freeze - Disable the GPEs and suspend EC transactions.
 113  */
 114 static int acpi_pm_freeze(void)
 115 {
 116         acpi_disable_all_gpes();
 117         acpi_os_wait_events_complete(NULL);
 118         acpi_ec_block_transactions();
 119         return 0;
 120 }
 121
 122 /**
 123  * acpi_pre_suspend - Enable wakeup devices, "freeze" EC and save NVS.
 124  */
 125 static int acpi_pm_pre_suspend(void)
 126 {
 127         acpi_pm_freeze();
 128         return suspend_nvs_save();
 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                 error = 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         suspend_nvs_free();
 171
 172         if (acpi_state == ACPI_STATE_S0)
 173                 return;
 174
 175         printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
 176                 acpi_state);
 177         acpi_disable_wakeup_devices(acpi_state);
 178         acpi_leave_sleep_state(acpi_state);
 179
 180         /* reset firmware waking vector */
 181         acpi_set_firmware_waking_vector((acpi_physical_address) 0);
 182
 183         acpi_target_sleep_state = ACPI_STATE_S0;
 184 }
 185
 186 /**
 187  *      acpi_pm_end - Finish up suspend sequence.
 188  */
 189 static void acpi_pm_end(void)
 190 {
 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 const 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 const 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         .callback = init_nvs_nosave,
 424         .ident = "Sony Vaio VPCEB1Z1E",
 425         .matches = {
 426                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 427                 DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB1Z1E"),
 428                 },
 429         },
 430         {
 431         .callback = init_nvs_nosave,
 432         .ident = "Sony Vaio VGN-NW130D",
 433         .matches = {
 434                 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 435                 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-NW130D"),
 436                 },
 437         },
 438         {
 439         .callback = init_nvs_nosave,
 440         .ident = "Averatec AV1020-ED2",
 441         .matches = {
 442                 DMI_MATCH(DMI_SYS_VENDOR, "AVERATEC"),
 443                 DMI_MATCH(DMI_PRODUCT_NAME, "1000 Series"),
 444                 },
 445         },
 446         {},
 447 };
 448 #endif /* CONFIG_SUSPEND */
 449
 450 #ifdef CONFIG_HIBERNATION
 451 static unsigned long s4_hardware_signature;
 452 static struct acpi_table_facs *facs;
 453 static bool nosigcheck;
 454
 455 void __init acpi_no_s4_hw_signature(void)
 456 {
 457         nosigcheck = true;
 458 }
 459
 460 static int acpi_hibernation_begin(void)
 461 {
 462         int error;
 463
 464         error = nvs_nosave ? 0 : suspend_nvs_alloc();
 465         if (!error) {
 466                 acpi_target_sleep_state = ACPI_STATE_S4;
 467                 acpi_sleep_tts_switch(acpi_target_sleep_state);
 468         }
 469
 470         return error;
 471 }
 472
 473 static int acpi_hibernation_enter(void)
 474 {
 475         acpi_status status = AE_OK;
 476         unsigned long flags = 0;
 477
 478         ACPI_FLUSH_CPU_CACHE();
 479
 480         local_irq_save(flags);
 481         /* This shouldn't return.  If it returns, we have a problem */
 482         status = acpi_enter_sleep_state(ACPI_STATE_S4);
 483         /* Reprogram control registers and execute _BFS */
 484         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 485         local_irq_restore(flags);
 486
 487         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 488 }
 489
 490 static void acpi_hibernation_leave(void)
 491 {
 492         /*
 493          * If ACPI is not enabled by the BIOS and the boot kernel, we need to
 494          * enable it here.
 495          */
 496         acpi_enable();
 497         /* Reprogram control registers and execute _BFS */
 498         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 499         /* Check the hardware signature */
 500         if (facs && s4_hardware_signature != facs->hardware_signature) {
 501                 printk(KERN_EMERG "ACPI: Hardware changed while hibernated, "
 502                         "cannot resume!\n");
 503                 panic("ACPI S4 hardware signature mismatch");
 504         }
 505         /* Restore the NVS memory area */
 506         suspend_nvs_restore();
 507         /* Allow EC transactions to happen. */
 508         acpi_ec_unblock_transactions_early();
 509 }
 510
 511 static void acpi_pm_thaw(void)
 512 {
 513         acpi_ec_unblock_transactions();
 514         acpi_enable_all_runtime_gpes();
 515 }
 516
 517 static const struct platform_hibernation_ops acpi_hibernation_ops = {
 518         .begin = acpi_hibernation_begin,
 519         .end = acpi_pm_end,
 520         .pre_snapshot = acpi_pm_prepare,
 521         .finish = acpi_pm_finish,
 522         .prepare = acpi_pm_prepare,
 523         .enter = acpi_hibernation_enter,
 524         .leave = acpi_hibernation_leave,
 525         .pre_restore = acpi_pm_freeze,
 526         .restore_cleanup = acpi_pm_thaw,
 527 };
 528
 529 /**
 530  *      acpi_hibernation_begin_old - Set the target system sleep state to
 531  *              ACPI_STATE_S4 and execute the _PTS control method.  This
 532  *              function is used if the pre-ACPI 2.0 suspend ordering has been
 533  *              requested.
 534  */
 535 static int acpi_hibernation_begin_old(void)
 536 {
 537         int error;
 538         /*
 539          * The _TTS object should always be evaluated before the _PTS object.
 540          * When the old_suspended_ordering is true, the _PTS object is
 541          * evaluated in the acpi_sleep_prepare.
 542          */
 543         acpi_sleep_tts_switch(ACPI_STATE_S4);
 544
 545         error = acpi_sleep_prepare(ACPI_STATE_S4);
 546
 547         if (!error) {
 548                 if (!nvs_nosave)
 549                         error = suspend_nvs_alloc();
 550                 if (!error)
 551                         acpi_target_sleep_state = ACPI_STATE_S4;
 552         }
 553         return error;
 554 }
 555
 556 /*
 557  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 558  * been requested.
 559  */
 560 static const struct platform_hibernation_ops acpi_hibernation_ops_old = {
 561         .begin = acpi_hibernation_begin_old,
 562         .end = acpi_pm_end,
 563         .pre_snapshot = acpi_pm_pre_suspend,
 564         .prepare = acpi_pm_freeze,
 565         .finish = acpi_pm_finish,
 566         .enter = acpi_hibernation_enter,
 567         .leave = acpi_hibernation_leave,
 568         .pre_restore = acpi_pm_freeze,
 569         .restore_cleanup = acpi_pm_thaw,
 570         .recover = acpi_pm_finish,
 571 };
 572 #endif /* CONFIG_HIBERNATION */
 573
 574 int acpi_suspend(u32 acpi_state)
 575 {
 576         suspend_state_t states[] = {
 577                 [1] = PM_SUSPEND_STANDBY,
 578                 [3] = PM_SUSPEND_MEM,
 579                 [5] = PM_SUSPEND_MAX
 580         };
 581
 582         if (acpi_state < 6 && states[acpi_state])
 583                 return pm_suspend(states[acpi_state]);
 584         if (acpi_state == 4)
 585                 return hibernate();
 586         return -EINVAL;
 587 }
 588
 589 #ifdef CONFIG_PM
 590 /**
 591  *      acpi_pm_device_sleep_state - return preferred power state of ACPI device
 592  *              in the system sleep state given by %acpi_target_sleep_state
 593  *      @dev: device to examine; its driver model wakeup flags control
 594  *              whether it should be able to wake up the system
 595  *      @d_min_p: used to store the upper limit of allowed states range
 596  *      Return value: preferred power state of the device on success, -ENODEV on
 597  *              failure (ie. if there's no 'struct acpi_device' for @dev)
 598  *
 599  *      Find the lowest power (highest number) ACPI device power state that
 600  *      device @dev can be in while the system is in the sleep state represented
 601  *      by %acpi_target_sleep_state.  If @wake is nonzero, the device should be
 602  *      able to wake up the system from this sleep state.  If @d_min_p is set,
 603  *      the highest power (lowest number) device power state of @dev allowed
 604  *      in this system sleep state is stored at the location pointed to by it.
 605  *
 606  *      The caller must ensure that @dev is valid before using this function.
 607  *      The caller is also responsible for figuring out if the device is
 608  *      supposed to be able to wake up the system and passing this information
 609  *      via @wake.
 610  */
 611
 612 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p)
 613 {
 614         acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
 615         struct acpi_device *adev;
 616         char acpi_method[] = "_SxD";
 617         unsigned long long d_min, d_max;
 618
 619         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
 620                 printk(KERN_DEBUG "ACPI handle has no context!\n");
 621                 return -ENODEV;
 622         }
 623
 624         acpi_method[2] = '0' + acpi_target_sleep_state;
 625         /*
 626          * If the sleep state is S0, we will return D3, but if the device has
 627          * _S0W, we will use the value from _S0W
 628          */
 629         d_min = ACPI_STATE_D0;
 630         d_max = ACPI_STATE_D3;
 631
 632         /*
 633          * If present, _SxD methods return the minimum D-state (highest power
 634          * state) we can use for the corresponding S-states.  Otherwise, the
 635          * minimum D-state is D0 (ACPI 3.x).
 636          *
 637          * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
 638          * provided -- that's our fault recovery, we ignore retval.
 639          */
 640         if (acpi_target_sleep_state > ACPI_STATE_S0)
 641                 acpi_evaluate_integer(handle, acpi_method, NULL, &d_min);
 642
 643         /*
 644          * If _PRW says we can wake up the system from the target sleep state,
 645          * the D-state returned by _SxD is sufficient for that (we assume a
 646          * wakeup-aware driver if wake is set).  Still, if _SxW exists
 647          * (ACPI 3.x), it should return the maximum (lowest power) D-state that
 648          * can wake the system.  _S0W may be valid, too.
 649          */
 650         if (acpi_target_sleep_state == ACPI_STATE_S0 ||
 651             (device_may_wakeup(dev) &&
 652              adev->wakeup.sleep_state <= acpi_target_sleep_state)) {
 653                 acpi_status status;
 654
 655                 acpi_method[3] = 'W';
 656                 status = acpi_evaluate_integer(handle, acpi_method, NULL,
 657                                                 &d_max);
 658                 if (ACPI_FAILURE(status)) {
 659                         if (acpi_target_sleep_state != ACPI_STATE_S0 ||
 660                             status != AE_NOT_FOUND)
 661                                 d_max = d_min;
 662                 } else if (d_max < d_min) {
 663                         /* Warn the user of the broken DSDT */
 664                         printk(KERN_WARNING "ACPI: Wrong value from %s\n",
 665                                 acpi_method);
 666                         /* Sanitize it */
 667                         d_min = d_max;
 668                 }
 669         }
 670
 671         if (d_min_p)
 672                 *d_min_p = d_min;
 673         return d_max;
 674 }
 675 #endif /* CONFIG_PM */
 676
 677 #ifdef CONFIG_PM_SLEEP
 678 /**
 679  *      acpi_pm_device_sleep_wake - enable or disable the system wake-up
 680  *                                  capability of given device
 681  *      @dev: device to handle
 682  *      @enable: 'true' - enable, 'false' - disable the wake-up capability
 683  */
 684 int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
 685 {
 686         acpi_handle handle;
 687         struct acpi_device *adev;
 688         int error;
 689
 690         if (!device_can_wakeup(dev))
 691                 return -EINVAL;
 692
 693         handle = DEVICE_ACPI_HANDLE(dev);
 694         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
 695                 dev_dbg(dev, "ACPI handle has no context in %s!\n", __func__);
 696                 return -ENODEV;
 697         }
 698
 699         error = enable ?
 700                 acpi_enable_wakeup_device_power(adev, acpi_target_sleep_state) :
 701                 acpi_disable_wakeup_device_power(adev);
 702         if (!error)
 703                 dev_info(dev, "wake-up capability %s by ACPI\n",
 704                                 enable ? "enabled" : "disabled");
 705
 706         return error;
 707 }
 708 #endif  /* CONFIG_PM_SLEEP */
 709
 710 static void acpi_power_off_prepare(void)
 711 {
 712         /* Prepare to power off the system */
 713         acpi_sleep_prepare(ACPI_STATE_S5);
 714         acpi_disable_all_gpes();
 715 }
 716
 717 static void acpi_power_off(void)
 718 {
 719         /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
 720         printk(KERN_DEBUG "%s called\n", __func__);
 721         local_irq_disable();
 722         acpi_enter_sleep_state(ACPI_STATE_S5);
 723 }
 724
 725 /*
 726  * ACPI 2.0 created the optional _GTS and _BFS,
 727  * but industry adoption has been neither rapid nor broad.
 728  *
 729  * Linux gets into trouble when it executes poorly validated
 730  * paths through the BIOS, so disable _GTS and _BFS by default,
 731  * but do speak up and offer the option to enable them.
 732  */
 733 static void __init acpi_gts_bfs_check(void)
 734 {
 735         acpi_handle dummy;
 736
 737         if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__GTS, &dummy)))
 738         {
 739                 printk(KERN_NOTICE PREFIX "BIOS offers _GTS\n");
 740                 printk(KERN_NOTICE PREFIX "If \"acpi.gts=1\" improves suspend, "
 741                         "please notify linux-acpi@vger.kernel.org\n");
 742         }
 743         if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__BFS, &dummy)))
 744         {
 745                 printk(KERN_NOTICE PREFIX "BIOS offers _BFS\n");
 746                 printk(KERN_NOTICE PREFIX "If \"acpi.bfs=1\" improves resume, "
 747                         "please notify linux-acpi@vger.kernel.org\n");
 748         }
 749 }
 750
 751 int __init acpi_sleep_init(void)
 752 {
 753         acpi_status status;
 754         u8 type_a, type_b;
 755 #ifdef CONFIG_SUSPEND
 756         int i = 0;
 757
 758         dmi_check_system(acpisleep_dmi_table);
 759 #endif
 760
 761         if (acpi_disabled)
 762                 return 0;
 763
 764         sleep_states[ACPI_STATE_S0] = 1;
 765         printk(KERN_INFO PREFIX "(supports S0");
 766
 767 #ifdef CONFIG_SUSPEND
 768         for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++) {
 769                 status = acpi_get_sleep_type_data(i, &type_a, &type_b);
 770                 if (ACPI_SUCCESS(status)) {
 771                         sleep_states[i] = 1;
 772                         printk(" S%d", i);
 773                 }
 774         }
 775
 776         suspend_set_ops(old_suspend_ordering ?
 777                 &acpi_suspend_ops_old : &acpi_suspend_ops);
 778 #endif
 779
 780 #ifdef CONFIG_HIBERNATION
 781         status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b);
 782         if (ACPI_SUCCESS(status)) {
 783                 hibernation_set_ops(old_suspend_ordering ?
 784                         &acpi_hibernation_ops_old : &acpi_hibernation_ops);
 785                 sleep_states[ACPI_STATE_S4] = 1;
 786                 printk(" S4");
 787                 if (!nosigcheck) {
 788                         acpi_get_table(ACPI_SIG_FACS, 1,
 789                                 (struct acpi_table_header **)&facs);
 790                         if (facs)
 791                                 s4_hardware_signature =
 792                                         facs->hardware_signature;
 793                 }
 794         }
 795 #endif
 796         status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
 797         if (ACPI_SUCCESS(status)) {
 798                 sleep_states[ACPI_STATE_S5] = 1;
 799                 printk(" S5");
 800                 pm_power_off_prepare = acpi_power_off_prepare;
 801                 pm_power_off = acpi_power_off;
 802         }
 803         printk(")\n");
 804         /*
 805          * Register the tts_notifier to reboot notifier list so that the _TTS
 806          * object can also be evaluated when the system enters S5.
 807          */
 808         register_reboot_notifier(&tts_notifier);
 809         acpi_gts_bfs_check();
 810         return 0;
 811 }