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