1/* 2 * drivers/acpi/device_pm.c - ACPI device power management routines. 3 * 4 * Copyright (C) 2012, Intel Corp. 5 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 6 * 7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License version 2 as published 11 * by the Free Software Foundation. 12 * 13 * This program is distributed in the hope that it will be useful, but 14 * WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License along 19 * with this program; if not, write to the Free Software Foundation, Inc., 20 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. 21 * 22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 23 */ 24 25#include <linux/acpi.h> 26#include <linux/export.h> 27#include <linux/mutex.h> 28#include <linux/pm_qos.h> 29#include <linux/pm_runtime.h> 30 31#include "internal.h" 32 33#define _COMPONENT ACPI_POWER_COMPONENT 34ACPI_MODULE_NAME("device_pm"); 35 36/** 37 * acpi_power_state_string - String representation of ACPI device power state. 38 * @state: ACPI device power state to return the string representation of. 39 */ 40const char *acpi_power_state_string(int state) 41{ 42 switch (state) { 43 case ACPI_STATE_D0: 44 return "D0"; 45 case ACPI_STATE_D1: 46 return "D1"; 47 case ACPI_STATE_D2: 48 return "D2"; 49 case ACPI_STATE_D3_HOT: 50 return "D3hot"; 51 case ACPI_STATE_D3_COLD: 52 return "D3cold"; 53 default: 54 return "(unknown)"; 55 } 56} 57 58/** 59 * acpi_device_get_power - Get power state of an ACPI device. 60 * @device: Device to get the power state of. 61 * @state: Place to store the power state of the device. 62 * 63 * This function does not update the device's power.state field, but it may 64 * update its parent's power.state field (when the parent's power state is 65 * unknown and the device's power state turns out to be D0). 66 */ 67int acpi_device_get_power(struct acpi_device *device, int *state) 68{ 69 int result = ACPI_STATE_UNKNOWN; 70 71 if (!device || !state) 72 return -EINVAL; 73 74 if (!device->flags.power_manageable) { 75 /* TBD: Non-recursive algorithm for walking up hierarchy. */ 76 *state = device->parent ? 77 device->parent->power.state : ACPI_STATE_D0; 78 goto out; 79 } 80 81 /* 82 * Get the device's power state from power resources settings and _PSC, 83 * if available. 84 */ 85 if (device->power.flags.power_resources) { 86 int error = acpi_power_get_inferred_state(device, &result); 87 if (error) 88 return error; 89 } 90 if (device->power.flags.explicit_get) { 91 acpi_handle handle = device->handle; 92 unsigned long long psc; 93 acpi_status status; 94 95 status = acpi_evaluate_integer(handle, "_PSC", NULL, &psc); 96 if (ACPI_FAILURE(status)) 97 return -ENODEV; 98 99 /* 100 * The power resources settings may indicate a power state 101 * shallower than the actual power state of the device. 102 * 103 * Moreover, on systems predating ACPI 4.0, if the device 104 * doesn't depend on any power resources and _PSC returns 3, 105 * that means "power off". We need to maintain compatibility 106 * with those systems. 107 */ 108 if (psc > result && psc < ACPI_STATE_D3_COLD) 109 result = psc; 110 else if (result == ACPI_STATE_UNKNOWN) 111 result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_COLD : psc; 112 } 113 114 /* 115 * If we were unsure about the device parent's power state up to this 116 * point, the fact that the device is in D0 implies that the parent has 117 * to be in D0 too, except if ignore_parent is set. 118 */ 119 if (!device->power.flags.ignore_parent && device->parent 120 && device->parent->power.state == ACPI_STATE_UNKNOWN 121 && result == ACPI_STATE_D0) 122 device->parent->power.state = ACPI_STATE_D0; 123 124 *state = result; 125 126 out: 127 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n", 128 device->pnp.bus_id, acpi_power_state_string(*state))); 129 130 return 0; 131} 132 133static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state) 134{ 135 if (adev->power.states[state].flags.explicit_set) { 136 char method[5] = { '_', 'P', 'S', '0' + state, '\0' }; 137 acpi_status status; 138 139 status = acpi_evaluate_object(adev->handle, method, NULL, NULL); 140 if (ACPI_FAILURE(status)) 141 return -ENODEV; 142 } 143 return 0; 144} 145 146/** 147 * acpi_device_set_power - Set power state of an ACPI device. 148 * @device: Device to set the power state of. 149 * @state: New power state to set. 150 * 151 * Callers must ensure that the device is power manageable before using this 152 * function. 153 */ 154int acpi_device_set_power(struct acpi_device *device, int state) 155{ 156 int result = 0; 157 bool cut_power = false; 158 159 if (!device || !device->flags.power_manageable 160 || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD)) 161 return -EINVAL; 162 163 /* Make sure this is a valid target state */ 164 165 if (state == device->power.state) { 166 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already in %s\n", 167 device->pnp.bus_id, 168 acpi_power_state_string(state))); 169 return 0; 170 } 171 172 if (!device->power.states[state].flags.valid) { 173 dev_warn(&device->dev, "Power state %s not supported\n", 174 acpi_power_state_string(state)); 175 return -ENODEV; 176 } 177 if (!device->power.flags.ignore_parent && 178 device->parent && (state < device->parent->power.state)) { 179 dev_warn(&device->dev, 180 "Cannot transition to power state %s for parent in %s\n", 181 acpi_power_state_string(state), 182 acpi_power_state_string(device->parent->power.state)); 183 return -ENODEV; 184 } 185 186 /* For D3cold we should first transition into D3hot. */ 187 if (state == ACPI_STATE_D3_COLD 188 && device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible) { 189 state = ACPI_STATE_D3_HOT; 190 cut_power = true; 191 } 192 193 if (state < device->power.state && state != ACPI_STATE_D0 194 && device->power.state >= ACPI_STATE_D3_HOT) { 195 dev_warn(&device->dev, 196 "Cannot transition to non-D0 state from D3\n"); 197 return -ENODEV; 198 } 199 200 /* 201 * Transition Power 202 * ---------------- 203 * In accordance with the ACPI specification first apply power (via 204 * power resources) and then evalute _PSx. 205 */ 206 if (device->power.flags.power_resources) { 207 result = acpi_power_transition(device, state); 208 if (result) 209 goto end; 210 } 211 result = acpi_dev_pm_explicit_set(device, state); 212 if (result) 213 goto end; 214 215 if (cut_power) { 216 device->power.state = state; 217 state = ACPI_STATE_D3_COLD; 218 result = acpi_power_transition(device, state); 219 } 220 221 end: 222 if (result) { 223 dev_warn(&device->dev, "Failed to change power state to %s\n", 224 acpi_power_state_string(state)); 225 } else { 226 device->power.state = state; 227 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 228 "Device [%s] transitioned to %s\n", 229 device->pnp.bus_id, 230 acpi_power_state_string(state))); 231 } 232 233 return result; 234} 235EXPORT_SYMBOL(acpi_device_set_power); 236 237int acpi_bus_set_power(acpi_handle handle, int state) 238{ 239 struct acpi_device *device; 240 int result; 241 242 result = acpi_bus_get_device(handle, &device); 243 if (result) 244 return result; 245 246 return acpi_device_set_power(device, state); 247} 248EXPORT_SYMBOL(acpi_bus_set_power); 249 250int acpi_bus_init_power(struct acpi_device *device) 251{ 252 int state; 253 int result; 254 255 if (!device) 256 return -EINVAL; 257 258 device->power.state = ACPI_STATE_UNKNOWN; 259 if (!acpi_device_is_present(device)) 260 return 0; 261 262 result = acpi_device_get_power(device, &state); 263 if (result) 264 return result; 265 266 if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) { 267 result = acpi_power_on_resources(device, state); 268 if (result) 269 return result; 270 271 result = acpi_dev_pm_explicit_set(device, state); 272 if (result) 273 return result; 274 } else if (state == ACPI_STATE_UNKNOWN) { 275 /* 276 * No power resources and missing _PSC? Cross fingers and make 277 * it D0 in hope that this is what the BIOS put the device into. 278 * [We tried to force D0 here by executing _PS0, but that broke 279 * Toshiba P870-303 in a nasty way.] 280 */ 281 state = ACPI_STATE_D0; 282 } 283 device->power.state = state; 284 return 0; 285} 286 287/** 288 * acpi_device_fix_up_power - Force device with missing _PSC into D0. 289 * @device: Device object whose power state is to be fixed up. 290 * 291 * Devices without power resources and _PSC, but having _PS0 and _PS3 defined, 292 * are assumed to be put into D0 by the BIOS. However, in some cases that may 293 * not be the case and this function should be used then. 294 */ 295int acpi_device_fix_up_power(struct acpi_device *device) 296{ 297 int ret = 0; 298 299 if (!device->power.flags.power_resources 300 && !device->power.flags.explicit_get 301 && device->power.state == ACPI_STATE_D0) 302 ret = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0); 303 304 return ret; 305} 306 307int acpi_device_update_power(struct acpi_device *device, int *state_p) 308{ 309 int state; 310 int result; 311 312 if (device->power.state == ACPI_STATE_UNKNOWN) { 313 result = acpi_bus_init_power(device); 314 if (!result && state_p) 315 *state_p = device->power.state; 316 317 return result; 318 } 319 320 result = acpi_device_get_power(device, &state); 321 if (result) 322 return result; 323 324 if (state == ACPI_STATE_UNKNOWN) { 325 state = ACPI_STATE_D0; 326 result = acpi_device_set_power(device, state); 327 if (result) 328 return result; 329 } else { 330 if (device->power.flags.power_resources) { 331 /* 332 * We don't need to really switch the state, bu we need 333 * to update the power resources' reference counters. 334 */ 335 result = acpi_power_transition(device, state); 336 if (result) 337 return result; 338 } 339 device->power.state = state; 340 } 341 if (state_p) 342 *state_p = state; 343 344 return 0; 345} 346EXPORT_SYMBOL_GPL(acpi_device_update_power); 347 348int acpi_bus_update_power(acpi_handle handle, int *state_p) 349{ 350 struct acpi_device *device; 351 int result; 352 353 result = acpi_bus_get_device(handle, &device); 354 return result ? result : acpi_device_update_power(device, state_p); 355} 356EXPORT_SYMBOL_GPL(acpi_bus_update_power); 357 358bool acpi_bus_power_manageable(acpi_handle handle) 359{ 360 struct acpi_device *device; 361 int result; 362 363 result = acpi_bus_get_device(handle, &device); 364 return result ? false : device->flags.power_manageable; 365} 366EXPORT_SYMBOL(acpi_bus_power_manageable); 367 368#ifdef CONFIG_PM 369static DEFINE_MUTEX(acpi_pm_notifier_lock); 370 371static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used) 372{ 373 struct acpi_device *adev; 374 375 if (val != ACPI_NOTIFY_DEVICE_WAKE) 376 return; 377 378 adev = acpi_bus_get_acpi_device(handle); 379 if (!adev) 380 return; 381 382 mutex_lock(&acpi_pm_notifier_lock); 383 384 if (adev->wakeup.flags.notifier_present) { 385 __pm_wakeup_event(adev->wakeup.ws, 0); 386 if (adev->wakeup.context.work.func) 387 queue_pm_work(&adev->wakeup.context.work); 388 } 389 390 mutex_unlock(&acpi_pm_notifier_lock); 391 392 acpi_bus_put_acpi_device(adev); 393} 394 395/** 396 * acpi_add_pm_notifier - Register PM notify handler for given ACPI device. 397 * @adev: ACPI device to add the notify handler for. 398 * @dev: Device to generate a wakeup event for while handling the notification. 399 * @work_func: Work function to execute when handling the notification. 400 * 401 * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of 402 * PM wakeup events. For example, wakeup events may be generated for bridges 403 * if one of the devices below the bridge is signaling wakeup, even if the 404 * bridge itself doesn't have a wakeup GPE associated with it. 405 */ 406acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev, 407 void (*work_func)(struct work_struct *work)) 408{ 409 acpi_status status = AE_ALREADY_EXISTS; 410 411 if (!dev && !work_func) 412 return AE_BAD_PARAMETER; 413 414 mutex_lock(&acpi_pm_notifier_lock); 415 416 if (adev->wakeup.flags.notifier_present) 417 goto out; 418 419 adev->wakeup.ws = wakeup_source_register(dev_name(&adev->dev)); 420 adev->wakeup.context.dev = dev; 421 if (work_func) 422 INIT_WORK(&adev->wakeup.context.work, work_func); 423 424 status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY, 425 acpi_pm_notify_handler, NULL); 426 if (ACPI_FAILURE(status)) 427 goto out; 428 429 adev->wakeup.flags.notifier_present = true; 430 431 out: 432 mutex_unlock(&acpi_pm_notifier_lock); 433 return status; 434} 435 436/** 437 * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device. 438 * @adev: ACPI device to remove the notifier from. 439 */ 440acpi_status acpi_remove_pm_notifier(struct acpi_device *adev) 441{ 442 acpi_status status = AE_BAD_PARAMETER; 443 444 mutex_lock(&acpi_pm_notifier_lock); 445 446 if (!adev->wakeup.flags.notifier_present) 447 goto out; 448 449 status = acpi_remove_notify_handler(adev->handle, 450 ACPI_SYSTEM_NOTIFY, 451 acpi_pm_notify_handler); 452 if (ACPI_FAILURE(status)) 453 goto out; 454 455 if (adev->wakeup.context.work.func) { 456 cancel_work_sync(&adev->wakeup.context.work); 457 adev->wakeup.context.work.func = NULL; 458 } 459 adev->wakeup.context.dev = NULL; 460 wakeup_source_unregister(adev->wakeup.ws); 461 462 adev->wakeup.flags.notifier_present = false; 463 464 out: 465 mutex_unlock(&acpi_pm_notifier_lock); 466 return status; 467} 468 469bool acpi_bus_can_wakeup(acpi_handle handle) 470{ 471 struct acpi_device *device; 472 int result; 473 474 result = acpi_bus_get_device(handle, &device); 475 return result ? false : device->wakeup.flags.valid; 476} 477EXPORT_SYMBOL(acpi_bus_can_wakeup); 478 479/** 480 * acpi_dev_pm_get_state - Get preferred power state of ACPI device. 481 * @dev: Device whose preferred target power state to return. 482 * @adev: ACPI device node corresponding to @dev. 483 * @target_state: System state to match the resultant device state. 484 * @d_min_p: Location to store the highest power state available to the device. 485 * @d_max_p: Location to store the lowest power state available to the device. 486 * 487 * Find the lowest power (highest number) and highest power (lowest number) ACPI 488 * device power states that the device can be in while the system is in the 489 * state represented by @target_state. Store the integer numbers representing 490 * those stats in the memory locations pointed to by @d_max_p and @d_min_p, 491 * respectively. 492 * 493 * Callers must ensure that @dev and @adev are valid pointers and that @adev 494 * actually corresponds to @dev before using this function. 495 * 496 * Returns 0 on success or -ENODATA when one of the ACPI methods fails or 497 * returns a value that doesn't make sense. The memory locations pointed to by 498 * @d_max_p and @d_min_p are only modified on success. 499 */ 500static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev, 501 u32 target_state, int *d_min_p, int *d_max_p) 502{ 503 char method[] = { '_', 'S', '0' + target_state, 'D', '\0' }; 504 acpi_handle handle = adev->handle; 505 unsigned long long ret; 506 int d_min, d_max; 507 bool wakeup = false; 508 acpi_status status; 509 510 /* 511 * If the system state is S0, the lowest power state the device can be 512 * in is D3cold, unless the device has _S0W and is supposed to signal 513 * wakeup, in which case the return value of _S0W has to be used as the 514 * lowest power state available to the device. 515 */ 516 d_min = ACPI_STATE_D0; 517 d_max = ACPI_STATE_D3_COLD; 518 519 /* 520 * If present, _SxD methods return the minimum D-state (highest power 521 * state) we can use for the corresponding S-states. Otherwise, the 522 * minimum D-state is D0 (ACPI 3.x). 523 */ 524 if (target_state > ACPI_STATE_S0) { 525 /* 526 * We rely on acpi_evaluate_integer() not clobbering the integer 527 * provided if AE_NOT_FOUND is returned. 528 */ 529 ret = d_min; 530 status = acpi_evaluate_integer(handle, method, NULL, &ret); 531 if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND) 532 || ret > ACPI_STATE_D3_COLD) 533 return -ENODATA; 534 535 /* 536 * We need to handle legacy systems where D3hot and D3cold are 537 * the same and 3 is returned in both cases, so fall back to 538 * D3cold if D3hot is not a valid state. 539 */ 540 if (!adev->power.states[ret].flags.valid) { 541 if (ret == ACPI_STATE_D3_HOT) 542 ret = ACPI_STATE_D3_COLD; 543 else 544 return -ENODATA; 545 } 546 d_min = ret; 547 wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid 548 && adev->wakeup.sleep_state >= target_state; 549 } else if (dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) != 550 PM_QOS_FLAGS_NONE) { 551 wakeup = adev->wakeup.flags.valid; 552 } 553 554 /* 555 * If _PRW says we can wake up the system from the target sleep state, 556 * the D-state returned by _SxD is sufficient for that (we assume a 557 * wakeup-aware driver if wake is set). Still, if _SxW exists 558 * (ACPI 3.x), it should return the maximum (lowest power) D-state that 559 * can wake the system. _S0W may be valid, too. 560 */ 561 if (wakeup) { 562 method[3] = 'W'; 563 status = acpi_evaluate_integer(handle, method, NULL, &ret); 564 if (status == AE_NOT_FOUND) { 565 if (target_state > ACPI_STATE_S0) 566 d_max = d_min; 567 } else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) { 568 /* Fall back to D3cold if ret is not a valid state. */ 569 if (!adev->power.states[ret].flags.valid) 570 ret = ACPI_STATE_D3_COLD; 571 572 d_max = ret > d_min ? ret : d_min; 573 } else { 574 return -ENODATA; 575 } 576 } 577 578 if (d_min_p) 579 *d_min_p = d_min; 580 581 if (d_max_p) 582 *d_max_p = d_max; 583 584 return 0; 585} 586 587/** 588 * acpi_pm_device_sleep_state - Get preferred power state of ACPI device. 589 * @dev: Device whose preferred target power state to return. 590 * @d_min_p: Location to store the upper limit of the allowed states range. 591 * @d_max_in: Deepest low-power state to take into consideration. 592 * Return value: Preferred power state of the device on success, -ENODEV 593 * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is 594 * incorrect, or -ENODATA on ACPI method failure. 595 * 596 * The caller must ensure that @dev is valid before using this function. 597 */ 598int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in) 599{ 600 struct acpi_device *adev; 601 int ret, d_min, d_max; 602 603 if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD) 604 return -EINVAL; 605 606 if (d_max_in > ACPI_STATE_D3_HOT) { 607 enum pm_qos_flags_status stat; 608 609 stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF); 610 if (stat == PM_QOS_FLAGS_ALL) 611 d_max_in = ACPI_STATE_D3_HOT; 612 } 613 614 adev = ACPI_COMPANION(dev); 615 if (!adev) { 616 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__); 617 return -ENODEV; 618 } 619 620 ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(), 621 &d_min, &d_max); 622 if (ret) 623 return ret; 624 625 if (d_max_in < d_min) 626 return -EINVAL; 627 628 if (d_max > d_max_in) { 629 for (d_max = d_max_in; d_max > d_min; d_max--) { 630 if (adev->power.states[d_max].flags.valid) 631 break; 632 } 633 } 634 635 if (d_min_p) 636 *d_min_p = d_min; 637 638 return d_max; 639} 640EXPORT_SYMBOL(acpi_pm_device_sleep_state); 641 642/** 643 * acpi_pm_notify_work_func - ACPI devices wakeup notification work function. 644 * @work: Work item to handle. 645 */ 646static void acpi_pm_notify_work_func(struct work_struct *work) 647{ 648 struct device *dev; 649 650 dev = container_of(work, struct acpi_device_wakeup_context, work)->dev; 651 if (dev) { 652 pm_wakeup_event(dev, 0); 653 pm_runtime_resume(dev); 654 } 655} 656 657/** 658 * acpi_device_wakeup - Enable/disable wakeup functionality for device. 659 * @adev: ACPI device to enable/disable wakeup functionality for. 660 * @target_state: State the system is transitioning into. 661 * @enable: Whether to enable or disable the wakeup functionality. 662 * 663 * Enable/disable the GPE associated with @adev so that it can generate 664 * wakeup signals for the device in response to external (remote) events and 665 * enable/disable device wakeup power. 666 * 667 * Callers must ensure that @adev is a valid ACPI device node before executing 668 * this function. 669 */ 670static int acpi_device_wakeup(struct acpi_device *adev, u32 target_state, 671 bool enable) 672{ 673 struct acpi_device_wakeup *wakeup = &adev->wakeup; 674 675 if (enable) { 676 acpi_status res; 677 int error; 678 679 error = acpi_enable_wakeup_device_power(adev, target_state); 680 if (error) 681 return error; 682 683 res = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number); 684 if (ACPI_FAILURE(res)) { 685 acpi_disable_wakeup_device_power(adev); 686 return -EIO; 687 } 688 } else { 689 acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number); 690 acpi_disable_wakeup_device_power(adev); 691 } 692 return 0; 693} 694 695#ifdef CONFIG_PM_RUNTIME 696/** 697 * acpi_pm_device_run_wake - Enable/disable remote wakeup for given device. 698 * @dev: Device to enable/disable the platform to wake up. 699 * @enable: Whether to enable or disable the wakeup functionality. 700 */ 701int acpi_pm_device_run_wake(struct device *phys_dev, bool enable) 702{ 703 struct acpi_device *adev; 704 705 if (!device_run_wake(phys_dev)) 706 return -EINVAL; 707 708 adev = ACPI_COMPANION(phys_dev); 709 if (!adev) { 710 dev_dbg(phys_dev, "ACPI companion missing in %s!\n", __func__); 711 return -ENODEV; 712 } 713 714 return acpi_device_wakeup(adev, ACPI_STATE_S0, enable); 715} 716EXPORT_SYMBOL(acpi_pm_device_run_wake); 717#endif /* CONFIG_PM_RUNTIME */ 718 719#ifdef CONFIG_PM_SLEEP 720/** 721 * acpi_pm_device_sleep_wake - Enable or disable device to wake up the system. 722 * @dev: Device to enable/desible to wake up the system from sleep states. 723 * @enable: Whether to enable or disable @dev to wake up the system. 724 */ 725int acpi_pm_device_sleep_wake(struct device *dev, bool enable) 726{ 727 struct acpi_device *adev; 728 int error; 729 730 if (!device_can_wakeup(dev)) 731 return -EINVAL; 732 733 adev = ACPI_COMPANION(dev); 734 if (!adev) { 735 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__); 736 return -ENODEV; 737 } 738 739 error = acpi_device_wakeup(adev, acpi_target_system_state(), enable); 740 if (!error) 741 dev_info(dev, "System wakeup %s by ACPI\n", 742 enable ? "enabled" : "disabled"); 743 744 return error; 745} 746#endif /* CONFIG_PM_SLEEP */ 747 748/** 749 * acpi_dev_pm_low_power - Put ACPI device into a low-power state. 750 * @dev: Device to put into a low-power state. 751 * @adev: ACPI device node corresponding to @dev. 752 * @system_state: System state to choose the device state for. 753 */ 754static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev, 755 u32 system_state) 756{ 757 int ret, state; 758 759 if (!acpi_device_power_manageable(adev)) 760 return 0; 761 762 ret = acpi_dev_pm_get_state(dev, adev, system_state, NULL, &state); 763 return ret ? ret : acpi_device_set_power(adev, state); 764} 765 766/** 767 * acpi_dev_pm_full_power - Put ACPI device into the full-power state. 768 * @adev: ACPI device node to put into the full-power state. 769 */ 770static int acpi_dev_pm_full_power(struct acpi_device *adev) 771{ 772 return acpi_device_power_manageable(adev) ? 773 acpi_device_set_power(adev, ACPI_STATE_D0) : 0; 774} 775 776#ifdef CONFIG_PM_RUNTIME 777/** 778 * acpi_dev_runtime_suspend - Put device into a low-power state using ACPI. 779 * @dev: Device to put into a low-power state. 780 * 781 * Put the given device into a runtime low-power state using the standard ACPI 782 * mechanism. Set up remote wakeup if desired, choose the state to put the 783 * device into (this checks if remote wakeup is expected to work too), and set 784 * the power state of the device. 785 */ 786int acpi_dev_runtime_suspend(struct device *dev) 787{ 788 struct acpi_device *adev = ACPI_COMPANION(dev); 789 bool remote_wakeup; 790 int error; 791 792 if (!adev) 793 return 0; 794 795 remote_wakeup = dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) > 796 PM_QOS_FLAGS_NONE; 797 error = acpi_device_wakeup(adev, ACPI_STATE_S0, remote_wakeup); 798 if (remote_wakeup && error) 799 return -EAGAIN; 800 801 error = acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0); 802 if (error) 803 acpi_device_wakeup(adev, ACPI_STATE_S0, false); 804 805 return error; 806} 807EXPORT_SYMBOL_GPL(acpi_dev_runtime_suspend); 808 809/** 810 * acpi_dev_runtime_resume - Put device into the full-power state using ACPI. 811 * @dev: Device to put into the full-power state. 812 * 813 * Put the given device into the full-power state using the standard ACPI 814 * mechanism at run time. Set the power state of the device to ACPI D0 and 815 * disable remote wakeup. 816 */ 817int acpi_dev_runtime_resume(struct device *dev) 818{ 819 struct acpi_device *adev = ACPI_COMPANION(dev); 820 int error; 821 822 if (!adev) 823 return 0; 824 825 error = acpi_dev_pm_full_power(adev); 826 acpi_device_wakeup(adev, ACPI_STATE_S0, false); 827 return error; 828} 829EXPORT_SYMBOL_GPL(acpi_dev_runtime_resume); 830 831/** 832 * acpi_subsys_runtime_suspend - Suspend device using ACPI. 833 * @dev: Device to suspend. 834 * 835 * Carry out the generic runtime suspend procedure for @dev and use ACPI to put 836 * it into a runtime low-power state. 837 */ 838int acpi_subsys_runtime_suspend(struct device *dev) 839{ 840 int ret = pm_generic_runtime_suspend(dev); 841 return ret ? ret : acpi_dev_runtime_suspend(dev); 842} 843EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend); 844 845/** 846 * acpi_subsys_runtime_resume - Resume device using ACPI. 847 * @dev: Device to Resume. 848 * 849 * Use ACPI to put the given device into the full-power state and carry out the 850 * generic runtime resume procedure for it. 851 */ 852int acpi_subsys_runtime_resume(struct device *dev) 853{ 854 int ret = acpi_dev_runtime_resume(dev); 855 return ret ? ret : pm_generic_runtime_resume(dev); 856} 857EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume); 858#endif /* CONFIG_PM_RUNTIME */ 859 860#ifdef CONFIG_PM_SLEEP 861/** 862 * acpi_dev_suspend_late - Put device into a low-power state using ACPI. 863 * @dev: Device to put into a low-power state. 864 * 865 * Put the given device into a low-power state during system transition to a 866 * sleep state using the standard ACPI mechanism. Set up system wakeup if 867 * desired, choose the state to put the device into (this checks if system 868 * wakeup is expected to work too), and set the power state of the device. 869 */ 870int acpi_dev_suspend_late(struct device *dev) 871{ 872 struct acpi_device *adev = ACPI_COMPANION(dev); 873 u32 target_state; 874 bool wakeup; 875 int error; 876 877 if (!adev) 878 return 0; 879 880 target_state = acpi_target_system_state(); 881 wakeup = device_may_wakeup(dev) && acpi_device_can_wakeup(adev); 882 error = acpi_device_wakeup(adev, target_state, wakeup); 883 if (wakeup && error) 884 return error; 885 886 error = acpi_dev_pm_low_power(dev, adev, target_state); 887 if (error) 888 acpi_device_wakeup(adev, ACPI_STATE_UNKNOWN, false); 889 890 return error; 891} 892EXPORT_SYMBOL_GPL(acpi_dev_suspend_late); 893 894/** 895 * acpi_dev_resume_early - Put device into the full-power state using ACPI. 896 * @dev: Device to put into the full-power state. 897 * 898 * Put the given device into the full-power state using the standard ACPI 899 * mechanism during system transition to the working state. Set the power 900 * state of the device to ACPI D0 and disable remote wakeup. 901 */ 902int acpi_dev_resume_early(struct device *dev) 903{ 904 struct acpi_device *adev = ACPI_COMPANION(dev); 905 int error; 906 907 if (!adev) 908 return 0; 909 910 error = acpi_dev_pm_full_power(adev); 911 acpi_device_wakeup(adev, ACPI_STATE_UNKNOWN, false); 912 return error; 913} 914EXPORT_SYMBOL_GPL(acpi_dev_resume_early); 915 916/** 917 * acpi_subsys_prepare - Prepare device for system transition to a sleep state. 918 * @dev: Device to prepare. 919 */ 920int acpi_subsys_prepare(struct device *dev) 921{ 922 struct acpi_device *adev = ACPI_COMPANION(dev); 923 u32 sys_target; 924 int ret, state; 925 926 ret = pm_generic_prepare(dev); 927 if (ret < 0) 928 return ret; 929 930 if (!adev || !pm_runtime_suspended(dev) 931 || device_may_wakeup(dev) != !!adev->wakeup.prepare_count) 932 return 0; 933 934 sys_target = acpi_target_system_state(); 935 if (sys_target == ACPI_STATE_S0) 936 return 1; 937 938 if (adev->power.flags.dsw_present) 939 return 0; 940 941 ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state); 942 return !ret && state == adev->power.state; 943} 944EXPORT_SYMBOL_GPL(acpi_subsys_prepare); 945 946/** 947 * acpi_subsys_complete - Finalize device's resume during system resume. 948 * @dev: Device to handle. 949 */ 950void acpi_subsys_complete(struct device *dev) 951{ 952 /* 953 * If the device had been runtime-suspended before the system went into 954 * the sleep state it is going out of and it has never been resumed till 955 * now, resume it in case the firmware powered it up. 956 */ 957 if (dev->power.direct_complete) 958 pm_request_resume(dev); 959} 960EXPORT_SYMBOL_GPL(acpi_subsys_complete); 961 962/** 963 * acpi_subsys_suspend - Run the device driver's suspend callback. 964 * @dev: Device to handle. 965 * 966 * Follow PCI and resume devices suspended at run time before running their 967 * system suspend callbacks. 968 */ 969int acpi_subsys_suspend(struct device *dev) 970{ 971 pm_runtime_resume(dev); 972 return pm_generic_suspend(dev); 973} 974EXPORT_SYMBOL_GPL(acpi_subsys_suspend); 975 976/** 977 * acpi_subsys_suspend_late - Suspend device using ACPI. 978 * @dev: Device to suspend. 979 * 980 * Carry out the generic late suspend procedure for @dev and use ACPI to put 981 * it into a low-power state during system transition into a sleep state. 982 */ 983int acpi_subsys_suspend_late(struct device *dev) 984{ 985 int ret = pm_generic_suspend_late(dev); 986 return ret ? ret : acpi_dev_suspend_late(dev); 987} 988EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late); 989 990/** 991 * acpi_subsys_resume_early - Resume device using ACPI. 992 * @dev: Device to Resume. 993 * 994 * Use ACPI to put the given device into the full-power state and carry out the 995 * generic early resume procedure for it during system transition into the 996 * working state. 997 */ 998int acpi_subsys_resume_early(struct device *dev) 999{ 1000 int ret = acpi_dev_resume_early(dev); 1001 return ret ? ret : pm_generic_resume_early(dev); 1002} 1003EXPORT_SYMBOL_GPL(acpi_subsys_resume_early); 1004 1005/** 1006 * acpi_subsys_freeze - Run the device driver's freeze callback. 1007 * @dev: Device to handle. 1008 */ 1009int acpi_subsys_freeze(struct device *dev) 1010{ 1011 /* 1012 * This used to be done in acpi_subsys_prepare() for all devices and 1013 * some drivers may depend on it, so do it here. Ideally, however, 1014 * runtime-suspended devices should not be touched during freeze/thaw 1015 * transitions. 1016 */ 1017 pm_runtime_resume(dev); 1018 return pm_generic_freeze(dev); 1019} 1020EXPORT_SYMBOL_GPL(acpi_subsys_freeze); 1021 1022#endif /* CONFIG_PM_SLEEP */ 1023 1024static struct dev_pm_domain acpi_general_pm_domain = { 1025 .ops = { 1026#ifdef CONFIG_PM_RUNTIME 1027 .runtime_suspend = acpi_subsys_runtime_suspend, 1028 .runtime_resume = acpi_subsys_runtime_resume, 1029#endif 1030#ifdef CONFIG_PM_SLEEP 1031 .prepare = acpi_subsys_prepare, 1032 .complete = acpi_subsys_complete, 1033 .suspend = acpi_subsys_suspend, 1034 .suspend_late = acpi_subsys_suspend_late, 1035 .resume_early = acpi_subsys_resume_early, 1036 .freeze = acpi_subsys_freeze, 1037 .poweroff = acpi_subsys_suspend, 1038 .poweroff_late = acpi_subsys_suspend_late, 1039 .restore_early = acpi_subsys_resume_early, 1040#endif 1041 }, 1042}; 1043 1044/** 1045 * acpi_dev_pm_detach - Remove ACPI power management from the device. 1046 * @dev: Device to take care of. 1047 * @power_off: Whether or not to try to remove power from the device. 1048 * 1049 * Remove the device from the general ACPI PM domain and remove its wakeup 1050 * notifier. If @power_off is set, additionally remove power from the device if 1051 * possible. 1052 * 1053 * Callers must ensure proper synchronization of this function with power 1054 * management callbacks. 1055 */ 1056static void acpi_dev_pm_detach(struct device *dev, bool power_off) 1057{ 1058 struct acpi_device *adev = ACPI_COMPANION(dev); 1059 1060 if (adev && dev->pm_domain == &acpi_general_pm_domain) { 1061 dev->pm_domain = NULL; 1062 acpi_remove_pm_notifier(adev); 1063 if (power_off) { 1064 /* 1065 * If the device's PM QoS resume latency limit or flags 1066 * have been exposed to user space, they have to be 1067 * hidden at this point, so that they don't affect the 1068 * choice of the low-power state to put the device into. 1069 */ 1070 dev_pm_qos_hide_latency_limit(dev); 1071 dev_pm_qos_hide_flags(dev); 1072 acpi_device_wakeup(adev, ACPI_STATE_S0, false); 1073 acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0); 1074 } 1075 } 1076} 1077 1078/** 1079 * acpi_dev_pm_attach - Prepare device for ACPI power management. 1080 * @dev: Device to prepare. 1081 * @power_on: Whether or not to power on the device. 1082 * 1083 * If @dev has a valid ACPI handle that has a valid struct acpi_device object 1084 * attached to it, install a wakeup notification handler for the device and 1085 * add it to the general ACPI PM domain. If @power_on is set, the device will 1086 * be put into the ACPI D0 state before the function returns. 1087 * 1088 * This assumes that the @dev's bus type uses generic power management callbacks 1089 * (or doesn't use any power management callbacks at all). 1090 * 1091 * Callers must ensure proper synchronization of this function with power 1092 * management callbacks. 1093 */ 1094int acpi_dev_pm_attach(struct device *dev, bool power_on) 1095{ 1096 struct acpi_device *adev = ACPI_COMPANION(dev); 1097 1098 if (!adev) 1099 return -ENODEV; 1100 1101 if (dev->pm_domain) 1102 return -EEXIST; 1103 1104 acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func); 1105 dev->pm_domain = &acpi_general_pm_domain; 1106 if (power_on) { 1107 acpi_dev_pm_full_power(adev); 1108 acpi_device_wakeup(adev, ACPI_STATE_S0, false); 1109 } 1110 1111 dev->pm_domain->detach = acpi_dev_pm_detach; 1112 return 0; 1113} 1114EXPORT_SYMBOL_GPL(acpi_dev_pm_attach); 1115#endif /* CONFIG_PM */ 1116