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