drivers/acpi/sleep/main.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
  19 #include <asm/io.h>
  20
  21 #include <acpi/acpi_bus.h>
  22 #include <acpi/acpi_drivers.h>
  23 #include "sleep.h"
  24
  25 u8 sleep_states[ACPI_S_STATE_COUNT];
  26
  27 static int acpi_sleep_prepare(u32 acpi_state)
  28 {
  29 #ifdef CONFIG_ACPI_SLEEP
  30         /* do we have a wakeup address for S2 and S3? */
  31         if (acpi_state == ACPI_STATE_S3) {
  32                 if (!acpi_wakeup_address) {
  33                         return -EFAULT;
  34                 }
  35                 acpi_set_firmware_waking_vector((acpi_physical_address)
  36                                                 virt_to_phys((void *)
  37                                                              acpi_wakeup_address));
  38
  39         }
  40         ACPI_FLUSH_CPU_CACHE();
  41         acpi_enable_wakeup_device_prep(acpi_state);
  42 #endif
  43         printk(KERN_INFO PREFIX "Preparing to enter system sleep state S%d\n",
  44                 acpi_state);
  45         acpi_enter_sleep_state_prep(acpi_state);
  46         return 0;
  47 }
  48
  49 #ifdef CONFIG_PM_SLEEP
  50 static u32 acpi_target_sleep_state = ACPI_STATE_S0;
  51
  52 /*
  53  * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
  54  * user to request that behavior by using the 'acpi_old_suspend_ordering'
  55  * kernel command line option that causes the following variable to be set.
  56  */
  57 static bool old_suspend_ordering;
  58
  59 void __init acpi_old_suspend_ordering(void)
  60 {
  61         old_suspend_ordering = true;
  62 }
  63
  64 /**
  65  *      acpi_pm_disable_gpes - Disable the GPEs.
  66  */
  67 static int acpi_pm_disable_gpes(void)
  68 {
  69         acpi_hw_disable_all_gpes();
  70         return 0;
  71 }
  72
  73 /**
  74  *      __acpi_pm_prepare - Prepare the platform to enter the target state.
  75  *
  76  *      If necessary, set the firmware waking vector and do arch-specific
  77  *      nastiness to get the wakeup code to the waking vector.
  78  */
  79 static int __acpi_pm_prepare(void)
  80 {
  81         int error = acpi_sleep_prepare(acpi_target_sleep_state);
  82
  83         if (error)
  84                 acpi_target_sleep_state = ACPI_STATE_S0;
  85         return error;
  86 }
  87
  88 /**
  89  *      acpi_pm_prepare - Prepare the platform to enter the target sleep
  90  *              state and disable the GPEs.
  91  */
  92 static int acpi_pm_prepare(void)
  93 {
  94         int error = __acpi_pm_prepare();
  95
  96         if (!error)
  97                 acpi_hw_disable_all_gpes();
  98         return error;
  99 }
 100
 101 /**
 102  *      acpi_pm_finish - Instruct the platform to leave a sleep state.
 103  *
 104  *      This is called after we wake back up (or if entering the sleep state
 105  *      failed).
 106  */
 107 static void acpi_pm_finish(void)
 108 {
 109         u32 acpi_state = acpi_target_sleep_state;
 110
 111         if (acpi_state == ACPI_STATE_S0)
 112                 return;
 113
 114         printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
 115                 acpi_state);
 116         acpi_disable_wakeup_device(acpi_state);
 117         acpi_leave_sleep_state(acpi_state);
 118
 119         /* reset firmware waking vector */
 120         acpi_set_firmware_waking_vector((acpi_physical_address) 0);
 121
 122         acpi_target_sleep_state = ACPI_STATE_S0;
 123 }
 124
 125 /**
 126  *      acpi_pm_end - Finish up suspend sequence.
 127  */
 128 static void acpi_pm_end(void)
 129 {
 130         /*
 131          * This is necessary in case acpi_pm_finish() is not called during a
 132          * failing transition to a sleep state.
 133          */
 134         acpi_target_sleep_state = ACPI_STATE_S0;
 135 }
 136 #endif /* CONFIG_PM_SLEEP */
 137
 138 #ifdef CONFIG_SUSPEND
 139 extern void do_suspend_lowlevel(void);
 140
 141 static u32 acpi_suspend_states[] = {
 142         [PM_SUSPEND_ON] = ACPI_STATE_S0,
 143         [PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
 144         [PM_SUSPEND_MEM] = ACPI_STATE_S3,
 145         [PM_SUSPEND_MAX] = ACPI_STATE_S5
 146 };
 147
 148 /**
 149  *      acpi_suspend_begin - Set the target system sleep state to the state
 150  *              associated with given @pm_state, if supported.
 151  */
 152 static int acpi_suspend_begin(suspend_state_t pm_state)
 153 {
 154         u32 acpi_state = acpi_suspend_states[pm_state];
 155         int error = 0;
 156
 157         if (sleep_states[acpi_state]) {
 158                 acpi_target_sleep_state = acpi_state;
 159         } else {
 160                 printk(KERN_ERR "ACPI does not support this state: %d\n",
 161                         pm_state);
 162                 error = -ENOSYS;
 163         }
 164         return error;
 165 }
 166
 167 /**
 168  *      acpi_suspend_enter - Actually enter a sleep state.
 169  *      @pm_state: ignored
 170  *
 171  *      Flush caches and go to sleep. For STR we have to call arch-specific
 172  *      assembly, which in turn call acpi_enter_sleep_state().
 173  *      It's unfortunate, but it works. Please fix if you're feeling frisky.
 174  */
 175 static int acpi_suspend_enter(suspend_state_t pm_state)
 176 {
 177         acpi_status status = AE_OK;
 178         unsigned long flags = 0;
 179         u32 acpi_state = acpi_target_sleep_state;
 180
 181         ACPI_FLUSH_CPU_CACHE();
 182
 183         /* Do arch specific saving of state. */
 184         if (acpi_state == ACPI_STATE_S3) {
 185                 int error = acpi_save_state_mem();
 186
 187                 if (error)
 188                         return error;
 189         }
 190
 191         local_irq_save(flags);
 192         acpi_enable_wakeup_device(acpi_state);
 193         switch (acpi_state) {
 194         case ACPI_STATE_S1:
 195                 barrier();
 196                 status = acpi_enter_sleep_state(acpi_state);
 197                 break;
 198
 199         case ACPI_STATE_S3:
 200                 do_suspend_lowlevel();
 201                 break;
 202         }
 203
 204         /* Reprogram control registers and execute _BFS */
 205         acpi_leave_sleep_state_prep(acpi_state);
 206
 207         /* ACPI 3.0 specs (P62) says that it's the responsibility
 208          * of the OSPM to clear the status bit [ implying that the
 209          * POWER_BUTTON event should not reach userspace ]
 210          */
 211         if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3))
 212                 acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
 213
 214         /*
 215          * Disable and clear GPE status before interrupt is enabled. Some GPEs
 216          * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
 217          * acpi_leave_sleep_state will reenable specific GPEs later
 218          */
 219         acpi_hw_disable_all_gpes();
 220
 221         local_irq_restore(flags);
 222         printk(KERN_DEBUG "Back to C!\n");
 223
 224         /* restore processor state */
 225         if (acpi_state == ACPI_STATE_S3)
 226                 acpi_restore_state_mem();
 227
 228         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 229 }
 230
 231 static int acpi_suspend_state_valid(suspend_state_t pm_state)
 232 {
 233         u32 acpi_state;
 234
 235         switch (pm_state) {
 236         case PM_SUSPEND_ON:
 237         case PM_SUSPEND_STANDBY:
 238         case PM_SUSPEND_MEM:
 239                 acpi_state = acpi_suspend_states[pm_state];
 240
 241                 return sleep_states[acpi_state];
 242         default:
 243                 return 0;
 244         }
 245 }
 246
 247 static struct platform_suspend_ops acpi_suspend_ops = {
 248         .valid = acpi_suspend_state_valid,
 249         .begin = acpi_suspend_begin,
 250         .prepare = acpi_pm_prepare,
 251         .enter = acpi_suspend_enter,
 252         .finish = acpi_pm_finish,
 253         .end = acpi_pm_end,
 254 };
 255
 256 /**
 257  *      acpi_suspend_begin_old - Set the target system sleep state to the
 258  *              state associated with given @pm_state, if supported, and
 259  *              execute the _PTS control method.  This function is used if the
 260  *              pre-ACPI 2.0 suspend ordering has been requested.
 261  */
 262 static int acpi_suspend_begin_old(suspend_state_t pm_state)
 263 {
 264         int error = acpi_suspend_begin(pm_state);
 265
 266         if (!error)
 267                 error = __acpi_pm_prepare();
 268         return error;
 269 }
 270
 271 /*
 272  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 273  * been requested.
 274  */
 275 static struct platform_suspend_ops acpi_suspend_ops_old = {
 276         .valid = acpi_suspend_state_valid,
 277         .begin = acpi_suspend_begin_old,
 278         .prepare = acpi_pm_disable_gpes,
 279         .enter = acpi_suspend_enter,
 280         .finish = acpi_pm_finish,
 281         .end = acpi_pm_end,
 282         .recover = acpi_pm_finish,
 283 };
 284 #endif /* CONFIG_SUSPEND */
 285
 286 #ifdef CONFIG_HIBERNATION
 287 static int acpi_hibernation_begin(void)
 288 {
 289         acpi_target_sleep_state = ACPI_STATE_S4;
 290         return 0;
 291 }
 292
 293 static int acpi_hibernation_enter(void)
 294 {
 295         acpi_status status = AE_OK;
 296         unsigned long flags = 0;
 297
 298         ACPI_FLUSH_CPU_CACHE();
 299
 300         local_irq_save(flags);
 301         acpi_enable_wakeup_device(ACPI_STATE_S4);
 302         /* This shouldn't return.  If it returns, we have a problem */
 303         status = acpi_enter_sleep_state(ACPI_STATE_S4);
 304         /* Reprogram control registers and execute _BFS */
 305         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 306         local_irq_restore(flags);
 307
 308         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 309 }
 310
 311 static void acpi_hibernation_leave(void)
 312 {
 313         /*
 314          * If ACPI is not enabled by the BIOS and the boot kernel, we need to
 315          * enable it here.
 316          */
 317         acpi_enable();
 318         /* Reprogram control registers and execute _BFS */
 319         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 320 }
 321
 322 static void acpi_pm_enable_gpes(void)
 323 {
 324         acpi_hw_enable_all_runtime_gpes();
 325 }
 326
 327 static struct platform_hibernation_ops acpi_hibernation_ops = {
 328         .begin = acpi_hibernation_begin,
 329         .end = acpi_pm_end,
 330         .pre_snapshot = acpi_pm_prepare,
 331         .finish = acpi_pm_finish,
 332         .prepare = acpi_pm_prepare,
 333         .enter = acpi_hibernation_enter,
 334         .leave = acpi_hibernation_leave,
 335         .pre_restore = acpi_pm_disable_gpes,
 336         .restore_cleanup = acpi_pm_enable_gpes,
 337 };
 338
 339 /**
 340  *      acpi_hibernation_begin_old - Set the target system sleep state to
 341  *              ACPI_STATE_S4 and execute the _PTS control method.  This
 342  *              function is used if the pre-ACPI 2.0 suspend ordering has been
 343  *              requested.
 344  */
 345 static int acpi_hibernation_begin_old(void)
 346 {
 347         int error = acpi_sleep_prepare(ACPI_STATE_S4);
 348
 349         if (!error)
 350                 acpi_target_sleep_state = ACPI_STATE_S4;
 351         return error;
 352 }
 353
 354 /*
 355  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 356  * been requested.
 357  */
 358 static struct platform_hibernation_ops acpi_hibernation_ops_old = {
 359         .begin = acpi_hibernation_begin_old,
 360         .end = acpi_pm_end,
 361         .pre_snapshot = acpi_pm_disable_gpes,
 362         .finish = acpi_pm_finish,
 363         .prepare = acpi_pm_disable_gpes,
 364         .enter = acpi_hibernation_enter,
 365         .leave = acpi_hibernation_leave,
 366         .pre_restore = acpi_pm_disable_gpes,
 367         .restore_cleanup = acpi_pm_enable_gpes,
 368         .recover = acpi_pm_finish,
 369 };
 370 #endif /* CONFIG_HIBERNATION */
 371
 372 int acpi_suspend(u32 acpi_state)
 373 {
 374         suspend_state_t states[] = {
 375                 [1] = PM_SUSPEND_STANDBY,
 376                 [3] = PM_SUSPEND_MEM,
 377                 [5] = PM_SUSPEND_MAX
 378         };
 379
 380         if (acpi_state < 6 && states[acpi_state])
 381                 return pm_suspend(states[acpi_state]);
 382         if (acpi_state == 4)
 383                 return hibernate();
 384         return -EINVAL;
 385 }
 386
 387 #ifdef CONFIG_PM_SLEEP
 388 /**
 389  *      acpi_pm_device_sleep_state - return preferred power state of ACPI device
 390  *              in the system sleep state given by %acpi_target_sleep_state
 391  *      @dev: device to examine; its driver model wakeup flags control
 392  *              whether it should be able to wake up the system
 393  *      @d_min_p: used to store the upper limit of allowed states range
 394  *      Return value: preferred power state of the device on success, -ENODEV on
 395  *              failure (ie. if there's no 'struct acpi_device' for @dev)
 396  *
 397  *      Find the lowest power (highest number) ACPI device power state that
 398  *      device @dev can be in while the system is in the sleep state represented
 399  *      by %acpi_target_sleep_state.  If @wake is nonzero, the device should be
 400  *      able to wake up the system from this sleep state.  If @d_min_p is set,
 401  *      the highest power (lowest number) device power state of @dev allowed
 402  *      in this system sleep state is stored at the location pointed to by it.
 403  *
 404  *      The caller must ensure that @dev is valid before using this function.
 405  *      The caller is also responsible for figuring out if the device is
 406  *      supposed to be able to wake up the system and passing this information
 407  *      via @wake.
 408  */
 409
 410 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p)
 411 {
 412         acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
 413         struct acpi_device *adev;
 414         char acpi_method[] = "_SxD";
 415         unsigned long d_min, d_max;
 416
 417         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
 418                 printk(KERN_DEBUG "ACPI handle has no context!\n");
 419                 return -ENODEV;
 420         }
 421
 422         acpi_method[2] = '0' + acpi_target_sleep_state;
 423         /*
 424          * If the sleep state is S0, we will return D3, but if the device has
 425          * _S0W, we will use the value from _S0W
 426          */
 427         d_min = ACPI_STATE_D0;
 428         d_max = ACPI_STATE_D3;
 429
 430         /*
 431          * If present, _SxD methods return the minimum D-state (highest power
 432          * state) we can use for the corresponding S-states.  Otherwise, the
 433          * minimum D-state is D0 (ACPI 3.x).
 434          *
 435          * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
 436          * provided -- that's our fault recovery, we ignore retval.
 437          */
 438         if (acpi_target_sleep_state > ACPI_STATE_S0)
 439                 acpi_evaluate_integer(handle, acpi_method, NULL, &d_min);
 440
 441         /*
 442          * If _PRW says we can wake up the system from the target sleep state,
 443          * the D-state returned by _SxD is sufficient for that (we assume a
 444          * wakeup-aware driver if wake is set).  Still, if _SxW exists
 445          * (ACPI 3.x), it should return the maximum (lowest power) D-state that
 446          * can wake the system.  _S0W may be valid, too.
 447          */
 448         if (acpi_target_sleep_state == ACPI_STATE_S0 ||
 449             (device_may_wakeup(dev) && adev->wakeup.state.enabled &&
 450              adev->wakeup.sleep_state <= acpi_target_sleep_state)) {
 451                 acpi_status status;
 452
 453                 acpi_method[3] = 'W';
 454                 status = acpi_evaluate_integer(handle, acpi_method, NULL,
 455                                                 &d_max);
 456                 if (ACPI_FAILURE(status)) {
 457                         d_max = d_min;
 458                 } else if (d_max < d_min) {
 459                         /* Warn the user of the broken DSDT */
 460                         printk(KERN_WARNING "ACPI: Wrong value from %s\n",
 461                                 acpi_method);
 462                         /* Sanitize it */
 463                         d_min = d_max;
 464                 }
 465         }
 466
 467         if (d_min_p)
 468                 *d_min_p = d_min;
 469         return d_max;
 470 }
 471
 472 /**
 473  *      acpi_pm_device_sleep_wake - enable or disable the system wake-up
 474  *                                  capability of given device
 475  *      @dev: device to handle
 476  *      @enable: 'true' - enable, 'false' - disable the wake-up capability
 477  */
 478 int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
 479 {
 480         acpi_handle handle;
 481         struct acpi_device *adev;
 482
 483         if (!device_may_wakeup(dev))
 484                 return -EINVAL;
 485
 486         handle = DEVICE_ACPI_HANDLE(dev);
 487         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
 488                 printk(KERN_DEBUG "ACPI handle has no context!\n");
 489                 return -ENODEV;
 490         }
 491
 492         return enable ?
 493                 acpi_enable_wakeup_device_power(adev, acpi_target_sleep_state) :
 494                 acpi_disable_wakeup_device_power(adev);
 495 }
 496 #endif
 497
 498 static void acpi_power_off_prepare(void)
 499 {
 500         /* Prepare to power off the system */
 501         acpi_sleep_prepare(ACPI_STATE_S5);
 502         acpi_hw_disable_all_gpes();
 503 }
 504
 505 static void acpi_power_off(void)
 506 {
 507         /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
 508         printk("%s called\n", __func__);
 509         local_irq_disable();
 510         acpi_enable_wakeup_device(ACPI_STATE_S5);
 511         acpi_enter_sleep_state(ACPI_STATE_S5);
 512 }
 513
 514 int __init acpi_sleep_init(void)
 515 {
 516         acpi_status status;
 517         u8 type_a, type_b;
 518 #ifdef CONFIG_SUSPEND
 519         int i = 0;
 520 #endif
 521
 522         if (acpi_disabled)
 523                 return 0;
 524
 525         sleep_states[ACPI_STATE_S0] = 1;
 526         printk(KERN_INFO PREFIX "(supports S0");
 527
 528 #ifdef CONFIG_SUSPEND
 529         for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++) {
 530                 status = acpi_get_sleep_type_data(i, &type_a, &type_b);
 531                 if (ACPI_SUCCESS(status)) {
 532                         sleep_states[i] = 1;
 533                         printk(" S%d", i);
 534                 }
 535         }
 536
 537         suspend_set_ops(old_suspend_ordering ?
 538                 &acpi_suspend_ops_old : &acpi_suspend_ops);
 539 #endif
 540
 541 #ifdef CONFIG_HIBERNATION
 542         status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b);
 543         if (ACPI_SUCCESS(status)) {
 544                 hibernation_set_ops(old_suspend_ordering ?
 545                         &acpi_hibernation_ops_old : &acpi_hibernation_ops);
 546                 sleep_states[ACPI_STATE_S4] = 1;
 547                 printk(" S4");
 548         }
 549 #endif
 550         status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
 551         if (ACPI_SUCCESS(status)) {
 552                 sleep_states[ACPI_STATE_S5] = 1;
 553                 printk(" S5");
 554                 pm_power_off_prepare = acpi_power_off_prepare;
 555                 pm_power_off = acpi_power_off;
 556         }
 557         printk(")\n");
 558         return 0;
 559 }