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(
  36                                 (acpi_physical_address)acpi_wakeup_address);
  37
  38         }
  39         ACPI_FLUSH_CPU_CACHE();
  40         acpi_enable_wakeup_device_prep(acpi_state);
  41 #endif
  42         printk(KERN_INFO PREFIX "Preparing to enter system sleep state S%d\n",
  43                 acpi_state);
  44         acpi_enter_sleep_state_prep(acpi_state);
  45         return 0;
  46 }
  47
  48 #ifdef CONFIG_PM_SLEEP
  49 static u32 acpi_target_sleep_state = ACPI_STATE_S0;
  50
  51 /*
  52  * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
  53  * user to request that behavior by using the 'acpi_old_suspend_ordering'
  54  * kernel command line option that causes the following variable to be set.
  55  */
  56 static bool old_suspend_ordering;
  57
  58 void __init acpi_old_suspend_ordering(void)
  59 {
  60         old_suspend_ordering = true;
  61 }
  62
  63 /**
  64  *      acpi_pm_disable_gpes - Disable the GPEs.
  65  */
  66 static int acpi_pm_disable_gpes(void)
  67 {
  68         acpi_hw_disable_all_gpes();
  69         return 0;
  70 }
  71
  72 /**
  73  *      __acpi_pm_prepare - Prepare the platform to enter the target state.
  74  *
  75  *      If necessary, set the firmware waking vector and do arch-specific
  76  *      nastiness to get the wakeup code to the waking vector.
  77  */
  78 static int __acpi_pm_prepare(void)
  79 {
  80         int error = acpi_sleep_prepare(acpi_target_sleep_state);
  81
  82         if (error)
  83                 acpi_target_sleep_state = ACPI_STATE_S0;
  84         return error;
  85 }
  86
  87 /**
  88  *      acpi_pm_prepare - Prepare the platform to enter the target sleep
  89  *              state and disable the GPEs.
  90  */
  91 static int acpi_pm_prepare(void)
  92 {
  93         int error = __acpi_pm_prepare();
  94
  95         if (!error)
  96                 acpi_hw_disable_all_gpes();
  97         return error;
  98 }
  99
 100 /**
 101  *      acpi_pm_finish - Instruct the platform to leave a sleep state.
 102  *
 103  *      This is called after we wake back up (or if entering the sleep state
 104  *      failed).
 105  */
 106 static void acpi_pm_finish(void)
 107 {
 108         u32 acpi_state = acpi_target_sleep_state;
 109
 110         if (acpi_state == ACPI_STATE_S0)
 111                 return;
 112
 113         printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
 114                 acpi_state);
 115         acpi_disable_wakeup_device(acpi_state);
 116         acpi_leave_sleep_state(acpi_state);
 117
 118         /* reset firmware waking vector */
 119         acpi_set_firmware_waking_vector((acpi_physical_address) 0);
 120
 121         acpi_target_sleep_state = ACPI_STATE_S0;
 122 }
 123
 124 /**
 125  *      acpi_pm_end - Finish up suspend sequence.
 126  */
 127 static void acpi_pm_end(void)
 128 {
 129         /*
 130          * This is necessary in case acpi_pm_finish() is not called during a
 131          * failing transition to a sleep state.
 132          */
 133         acpi_target_sleep_state = ACPI_STATE_S0;
 134 }
 135 #endif /* CONFIG_PM_SLEEP */
 136
 137 #ifdef CONFIG_SUSPEND
 138 extern void do_suspend_lowlevel(void);
 139
 140 static u32 acpi_suspend_states[] = {
 141         [PM_SUSPEND_ON] = ACPI_STATE_S0,
 142         [PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
 143         [PM_SUSPEND_MEM] = ACPI_STATE_S3,
 144         [PM_SUSPEND_MAX] = ACPI_STATE_S5
 145 };
 146
 147 /**
 148  *      acpi_suspend_begin - Set the target system sleep state to the state
 149  *              associated with given @pm_state, if supported.
 150  */
 151 static int acpi_suspend_begin(suspend_state_t pm_state)
 152 {
 153         u32 acpi_state = acpi_suspend_states[pm_state];
 154         int error = 0;
 155
 156         if (sleep_states[acpi_state]) {
 157                 acpi_target_sleep_state = acpi_state;
 158         } else {
 159                 printk(KERN_ERR "ACPI does not support this state: %d\n",
 160                         pm_state);
 161                 error = -ENOSYS;
 162         }
 163         return error;
 164 }
 165
 166 /**
 167  *      acpi_suspend_enter - Actually enter a sleep state.
 168  *      @pm_state: ignored
 169  *
 170  *      Flush caches and go to sleep. For STR we have to call arch-specific
 171  *      assembly, which in turn call acpi_enter_sleep_state().
 172  *      It's unfortunate, but it works. Please fix if you're feeling frisky.
 173  */
 174 static int acpi_suspend_enter(suspend_state_t pm_state)
 175 {
 176         acpi_status status = AE_OK;
 177         unsigned long flags = 0;
 178         u32 acpi_state = acpi_target_sleep_state;
 179
 180         ACPI_FLUSH_CPU_CACHE();
 181
 182         /* Do arch specific saving of state. */
 183         if (acpi_state == ACPI_STATE_S3) {
 184                 int error = acpi_save_state_mem();
 185
 186                 if (error)
 187                         return error;
 188         }
 189
 190         local_irq_save(flags);
 191         acpi_enable_wakeup_device(acpi_state);
 192         switch (acpi_state) {
 193         case ACPI_STATE_S1:
 194                 barrier();
 195                 status = acpi_enter_sleep_state(acpi_state);
 196                 break;
 197
 198         case ACPI_STATE_S3:
 199                 do_suspend_lowlevel();
 200                 break;
 201         }
 202
 203         /* Reprogram control registers and execute _BFS */
 204         acpi_leave_sleep_state_prep(acpi_state);
 205
 206         /* ACPI 3.0 specs (P62) says that it's the responsibility
 207          * of the OSPM to clear the status bit [ implying that the
 208          * POWER_BUTTON event should not reach userspace ]
 209          */
 210         if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3))
 211                 acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
 212
 213         /*
 214          * Disable and clear GPE status before interrupt is enabled. Some GPEs
 215          * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
 216          * acpi_leave_sleep_state will reenable specific GPEs later
 217          */
 218         acpi_hw_disable_all_gpes();
 219
 220         local_irq_restore(flags);
 221         printk(KERN_DEBUG "Back to C!\n");
 222
 223         /* restore processor state */
 224         if (acpi_state == ACPI_STATE_S3)
 225                 acpi_restore_state_mem();
 226
 227         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 228 }
 229
 230 static int acpi_suspend_state_valid(suspend_state_t pm_state)
 231 {
 232         u32 acpi_state;
 233
 234         switch (pm_state) {
 235         case PM_SUSPEND_ON:
 236         case PM_SUSPEND_STANDBY:
 237         case PM_SUSPEND_MEM:
 238                 acpi_state = acpi_suspend_states[pm_state];
 239
 240                 return sleep_states[acpi_state];
 241         default:
 242                 return 0;
 243         }
 244 }
 245
 246 static struct platform_suspend_ops acpi_suspend_ops = {
 247         .valid = acpi_suspend_state_valid,
 248         .begin = acpi_suspend_begin,
 249         .prepare = acpi_pm_prepare,
 250         .enter = acpi_suspend_enter,
 251         .finish = acpi_pm_finish,
 252         .end = acpi_pm_end,
 253 };
 254
 255 /**
 256  *      acpi_suspend_begin_old - Set the target system sleep state to the
 257  *              state associated with given @pm_state, if supported, and
 258  *              execute the _PTS control method.  This function is used if the
 259  *              pre-ACPI 2.0 suspend ordering has been requested.
 260  */
 261 static int acpi_suspend_begin_old(suspend_state_t pm_state)
 262 {
 263         int error = acpi_suspend_begin(pm_state);
 264
 265         if (!error)
 266                 error = __acpi_pm_prepare();
 267         return error;
 268 }
 269
 270 /*
 271  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 272  * been requested.
 273  */
 274 static struct platform_suspend_ops acpi_suspend_ops_old = {
 275         .valid = acpi_suspend_state_valid,
 276         .begin = acpi_suspend_begin_old,
 277         .prepare = acpi_pm_disable_gpes,
 278         .enter = acpi_suspend_enter,
 279         .finish = acpi_pm_finish,
 280         .end = acpi_pm_end,
 281         .recover = acpi_pm_finish,
 282 };
 283 #endif /* CONFIG_SUSPEND */
 284
 285 #ifdef CONFIG_HIBERNATION
 286 static unsigned long s4_hardware_signature;
 287 static struct acpi_table_facs *facs;
 288 static bool nosigcheck;
 289
 290 void __init acpi_no_s4_hw_signature(void)
 291 {
 292         nosigcheck = true;
 293 }
 294
 295 static int acpi_hibernation_begin(void)
 296 {
 297         acpi_target_sleep_state = ACPI_STATE_S4;
 298         return 0;
 299 }
 300
 301 static int acpi_hibernation_enter(void)
 302 {
 303         acpi_status status = AE_OK;
 304         unsigned long flags = 0;
 305
 306         ACPI_FLUSH_CPU_CACHE();
 307
 308         local_irq_save(flags);
 309         acpi_enable_wakeup_device(ACPI_STATE_S4);
 310         /* This shouldn't return.  If it returns, we have a problem */
 311         status = acpi_enter_sleep_state(ACPI_STATE_S4);
 312         /* Reprogram control registers and execute _BFS */
 313         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 314         local_irq_restore(flags);
 315
 316         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 317 }
 318
 319 static void acpi_hibernation_leave(void)
 320 {
 321         /*
 322          * If ACPI is not enabled by the BIOS and the boot kernel, we need to
 323          * enable it here.
 324          */
 325         acpi_enable();
 326         /* Reprogram control registers and execute _BFS */
 327         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 328         /* Check the hardware signature */
 329         if (facs && s4_hardware_signature != facs->hardware_signature) {
 330                 printk(KERN_EMERG "ACPI: Hardware changed while hibernated, "
 331                         "cannot resume!\n");
 332                 panic("ACPI S4 hardware signature mismatch");
 333         }
 334 }
 335
 336 static void acpi_pm_enable_gpes(void)
 337 {
 338         acpi_hw_enable_all_runtime_gpes();
 339 }
 340
 341 static struct platform_hibernation_ops acpi_hibernation_ops = {
 342         .begin = acpi_hibernation_begin,
 343         .end = acpi_pm_end,
 344         .pre_snapshot = acpi_pm_prepare,
 345         .finish = acpi_pm_finish,
 346         .prepare = acpi_pm_prepare,
 347         .enter = acpi_hibernation_enter,
 348         .leave = acpi_hibernation_leave,
 349         .pre_restore = acpi_pm_disable_gpes,
 350         .restore_cleanup = acpi_pm_enable_gpes,
 351 };
 352
 353 /**
 354  *      acpi_hibernation_begin_old - Set the target system sleep state to
 355  *              ACPI_STATE_S4 and execute the _PTS control method.  This
 356  *              function is used if the pre-ACPI 2.0 suspend ordering has been
 357  *              requested.
 358  */
 359 static int acpi_hibernation_begin_old(void)
 360 {
 361         int error = acpi_sleep_prepare(ACPI_STATE_S4);
 362
 363         if (!error)
 364                 acpi_target_sleep_state = ACPI_STATE_S4;
 365         return error;
 366 }
 367
 368 /*
 369  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 370  * been requested.
 371  */
 372 static struct platform_hibernation_ops acpi_hibernation_ops_old = {
 373         .begin = acpi_hibernation_begin_old,
 374         .end = acpi_pm_end,
 375         .pre_snapshot = acpi_pm_disable_gpes,
 376         .finish = acpi_pm_finish,
 377         .prepare = acpi_pm_disable_gpes,
 378         .enter = acpi_hibernation_enter,
 379         .leave = acpi_hibernation_leave,
 380         .pre_restore = acpi_pm_disable_gpes,
 381         .restore_cleanup = acpi_pm_enable_gpes,
 382         .recover = acpi_pm_finish,
 383 };
 384 #endif /* CONFIG_HIBERNATION */
 385
 386 int acpi_suspend(u32 acpi_state)
 387 {
 388         suspend_state_t states[] = {
 389                 [1] = PM_SUSPEND_STANDBY,
 390                 [3] = PM_SUSPEND_MEM,
 391                 [5] = PM_SUSPEND_MAX
 392         };
 393
 394         if (acpi_state < 6 && states[acpi_state])
 395                 return pm_suspend(states[acpi_state]);
 396         if (acpi_state == 4)
 397                 return hibernate();
 398         return -EINVAL;
 399 }
 400
 401 #ifdef CONFIG_PM_SLEEP
 402 /**
 403  *      acpi_pm_device_sleep_state - return preferred power state of ACPI device
 404  *              in the system sleep state given by %acpi_target_sleep_state
 405  *      @dev: device to examine; its driver model wakeup flags control
 406  *              whether it should be able to wake up the system
 407  *      @d_min_p: used to store the upper limit of allowed states range
 408  *      Return value: preferred power state of the device on success, -ENODEV on
 409  *              failure (ie. if there's no 'struct acpi_device' for @dev)
 410  *
 411  *      Find the lowest power (highest number) ACPI device power state that
 412  *      device @dev can be in while the system is in the sleep state represented
 413  *      by %acpi_target_sleep_state.  If @wake is nonzero, the device should be
 414  *      able to wake up the system from this sleep state.  If @d_min_p is set,
 415  *      the highest power (lowest number) device power state of @dev allowed
 416  *      in this system sleep state is stored at the location pointed to by it.
 417  *
 418  *      The caller must ensure that @dev is valid before using this function.
 419  *      The caller is also responsible for figuring out if the device is
 420  *      supposed to be able to wake up the system and passing this information
 421  *      via @wake.
 422  */
 423
 424 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p)
 425 {
 426         acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
 427         struct acpi_device *adev;
 428         char acpi_method[] = "_SxD";
 429         unsigned long d_min, d_max;
 430
 431         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
 432                 printk(KERN_DEBUG "ACPI handle has no context!\n");
 433                 return -ENODEV;
 434         }
 435
 436         acpi_method[2] = '0' + acpi_target_sleep_state;
 437         /*
 438          * If the sleep state is S0, we will return D3, but if the device has
 439          * _S0W, we will use the value from _S0W
 440          */
 441         d_min = ACPI_STATE_D0;
 442         d_max = ACPI_STATE_D3;
 443
 444         /*
 445          * If present, _SxD methods return the minimum D-state (highest power
 446          * state) we can use for the corresponding S-states.  Otherwise, the
 447          * minimum D-state is D0 (ACPI 3.x).
 448          *
 449          * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
 450          * provided -- that's our fault recovery, we ignore retval.
 451          */
 452         if (acpi_target_sleep_state > ACPI_STATE_S0)
 453                 acpi_evaluate_integer(handle, acpi_method, NULL, &d_min);
 454
 455         /*
 456          * If _PRW says we can wake up the system from the target sleep state,
 457          * the D-state returned by _SxD is sufficient for that (we assume a
 458          * wakeup-aware driver if wake is set).  Still, if _SxW exists
 459          * (ACPI 3.x), it should return the maximum (lowest power) D-state that
 460          * can wake the system.  _S0W may be valid, too.
 461          */
 462         if (acpi_target_sleep_state == ACPI_STATE_S0 ||
 463             (device_may_wakeup(dev) && adev->wakeup.state.enabled &&
 464              adev->wakeup.sleep_state <= acpi_target_sleep_state)) {
 465                 acpi_status status;
 466
 467                 acpi_method[3] = 'W';
 468                 status = acpi_evaluate_integer(handle, acpi_method, NULL,
 469                                                 &d_max);
 470                 if (ACPI_FAILURE(status)) {
 471                         d_max = d_min;
 472                 } else if (d_max < d_min) {
 473                         /* Warn the user of the broken DSDT */
 474                         printk(KERN_WARNING "ACPI: Wrong value from %s\n",
 475                                 acpi_method);
 476                         /* Sanitize it */
 477                         d_min = d_max;
 478                 }
 479         }
 480
 481         if (d_min_p)
 482                 *d_min_p = d_min;
 483         return d_max;
 484 }
 485
 486 /**
 487  *      acpi_pm_device_sleep_wake - enable or disable the system wake-up
 488  *                                  capability of given device
 489  *      @dev: device to handle
 490  *      @enable: 'true' - enable, 'false' - disable the wake-up capability
 491  */
 492 int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
 493 {
 494         acpi_handle handle;
 495         struct acpi_device *adev;
 496
 497         if (!device_may_wakeup(dev))
 498                 return -EINVAL;
 499
 500         handle = DEVICE_ACPI_HANDLE(dev);
 501         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
 502                 printk(KERN_DEBUG "ACPI handle has no context!\n");
 503                 return -ENODEV;
 504         }
 505
 506         return enable ?
 507                 acpi_enable_wakeup_device_power(adev, acpi_target_sleep_state) :
 508                 acpi_disable_wakeup_device_power(adev);
 509 }
 510 #endif
 511
 512 static void acpi_power_off_prepare(void)
 513 {
 514         /* Prepare to power off the system */
 515         acpi_sleep_prepare(ACPI_STATE_S5);
 516         acpi_hw_disable_all_gpes();
 517 }
 518
 519 static void acpi_power_off(void)
 520 {
 521         /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
 522         printk("%s called\n", __func__);
 523         local_irq_disable();
 524         acpi_enable_wakeup_device(ACPI_STATE_S5);
 525         acpi_enter_sleep_state(ACPI_STATE_S5);
 526 }
 527
 528 int __init acpi_sleep_init(void)
 529 {
 530         acpi_status status;
 531         u8 type_a, type_b;
 532 #ifdef CONFIG_SUSPEND
 533         int i = 0;
 534 #endif
 535
 536         if (acpi_disabled)
 537                 return 0;
 538
 539         sleep_states[ACPI_STATE_S0] = 1;
 540         printk(KERN_INFO PREFIX "(supports S0");
 541
 542 #ifdef CONFIG_SUSPEND
 543         for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++) {
 544                 status = acpi_get_sleep_type_data(i, &type_a, &type_b);
 545                 if (ACPI_SUCCESS(status)) {
 546                         sleep_states[i] = 1;
 547                         printk(" S%d", i);
 548                 }
 549         }
 550
 551         suspend_set_ops(old_suspend_ordering ?
 552                 &acpi_suspend_ops_old : &acpi_suspend_ops);
 553 #endif
 554
 555 #ifdef CONFIG_HIBERNATION
 556         status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b);
 557         if (ACPI_SUCCESS(status)) {
 558                 hibernation_set_ops(old_suspend_ordering ?
 559                         &acpi_hibernation_ops_old : &acpi_hibernation_ops);
 560                 sleep_states[ACPI_STATE_S4] = 1;
 561                 printk(" S4");
 562                 if (!nosigcheck) {
 563                         acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
 564                                 (struct acpi_table_header **)&facs);
 565                         if (facs)
 566                                 s4_hardware_signature =
 567                                         facs->hardware_signature;
 568                 }
 569         }
 570 #endif
 571         status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
 572         if (ACPI_SUCCESS(status)) {
 573                 sleep_states[ACPI_STATE_S5] = 1;
 574                 printk(" S5");
 575                 pm_power_off_prepare = acpi_power_off_prepare;
 576                 pm_power_off = acpi_power_off;
 577         }
 578         printk(")\n");
 579         return 0;
 580 }