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 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 19 */ 20 21 #include <linux/acpi.h> 22 #include <linux/export.h> 23 #include <linux/mutex.h> 24 #include <linux/pm_qos.h> 25 #include <linux/pm_domain.h> 26 #include <linux/pm_runtime.h> 27 28 #include "internal.h" 29 30 #define _COMPONENT ACPI_POWER_COMPONENT 31 ACPI_MODULE_NAME("device_pm"); 32 33 /** 34 * acpi_power_state_string - String representation of ACPI device power state. 35 * @state: ACPI device power state to return the string representation of. 36 */ 37 const char *acpi_power_state_string(int state) 38 { 39 switch (state) { 40 case ACPI_STATE_D0: 41 return "D0"; 42 case ACPI_STATE_D1: 43 return "D1"; 44 case ACPI_STATE_D2: 45 return "D2"; 46 case ACPI_STATE_D3_HOT: 47 return "D3hot"; 48 case ACPI_STATE_D3_COLD: 49 return "D3cold"; 50 default: 51 return "(unknown)"; 52 } 53 } 54 55 /** 56 * acpi_device_get_power - Get power state of an ACPI device. 57 * @device: Device to get the power state of. 58 * @state: Place to store the power state of the device. 59 * 60 * This function does not update the device's power.state field, but it may 61 * update its parent's power.state field (when the parent's power state is 62 * unknown and the device's power state turns out to be D0). 63 */ 64 int acpi_device_get_power(struct acpi_device *device, int *state) 65 { 66 int result = ACPI_STATE_UNKNOWN; 67 68 if (!device || !state) 69 return -EINVAL; 70 71 if (!device->flags.power_manageable) { 72 /* TBD: Non-recursive algorithm for walking up hierarchy. */ 73 *state = device->parent ? 74 device->parent->power.state : ACPI_STATE_D0; 75 goto out; 76 } 77 78 /* 79 * Get the device's power state from power resources settings and _PSC, 80 * if available. 81 */ 82 if (device->power.flags.power_resources) { 83 int error = acpi_power_get_inferred_state(device, &result); 84 if (error) 85 return error; 86 } 87 if (device->power.flags.explicit_get) { 88 acpi_handle handle = device->handle; 89 unsigned long long psc; 90 acpi_status status; 91 92 status = acpi_evaluate_integer(handle, "_PSC", NULL, &psc); 93 if (ACPI_FAILURE(status)) 94 return -ENODEV; 95 96 /* 97 * The power resources settings may indicate a power state 98 * shallower than the actual power state of the device, because 99 * the same power resources may be referenced by other devices. 100 * 101 * For systems predating ACPI 4.0 we assume that D3hot is the 102 * deepest state that can be supported. 103 */ 104 if (psc > result && psc < ACPI_STATE_D3_COLD) 105 result = psc; 106 else if (result == ACPI_STATE_UNKNOWN) 107 result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_HOT : psc; 108 } 109 110 /* 111 * If we were unsure about the device parent's power state up to this 112 * point, the fact that the device is in D0 implies that the parent has 113 * to be in D0 too, except if ignore_parent is set. 114 */ 115 if (!device->power.flags.ignore_parent && device->parent 116 && device->parent->power.state == ACPI_STATE_UNKNOWN 117 && result == ACPI_STATE_D0) 118 device->parent->power.state = ACPI_STATE_D0; 119 120 *state = result; 121 122 out: 123 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n", 124 device->pnp.bus_id, acpi_power_state_string(*state))); 125 126 return 0; 127 } 128 129 static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state) 130 { 131 if (adev->power.states[state].flags.explicit_set) { 132 char method[5] = { '_', 'P', 'S', '0' + state, '\0' }; 133 acpi_status status; 134 135 status = acpi_evaluate_object(adev->handle, method, NULL, NULL); 136 if (ACPI_FAILURE(status)) 137 return -ENODEV; 138 } 139 return 0; 140 } 141 142 /** 143 * acpi_device_set_power - Set power state of an ACPI device. 144 * @device: Device to set the power state of. 145 * @state: New power state to set. 146 * 147 * Callers must ensure that the device is power manageable before using this 148 * function. 149 */ 150 int acpi_device_set_power(struct acpi_device *device, int state) 151 { 152 int target_state = state; 153 int result = 0; 154 155 if (!device || !device->flags.power_manageable 156 || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD)) 157 return -EINVAL; 158 159 /* Make sure this is a valid target state */ 160 161 if (state == device->power.state) { 162 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already in %s\n", 163 device->pnp.bus_id, 164 acpi_power_state_string(state))); 165 return 0; 166 } 167 168 if (state == ACPI_STATE_D3_COLD) { 169 /* 170 * For transitions to D3cold we need to execute _PS3 and then 171 * possibly drop references to the power resources in use. 172 */ 173 state = ACPI_STATE_D3_HOT; 174 /* If _PR3 is not available, use D3hot as the target state. */ 175 if (!device->power.states[ACPI_STATE_D3_COLD].flags.valid) 176 target_state = state; 177 } else if (!device->power.states[state].flags.valid) { 178 dev_warn(&device->dev, "Power state %s not supported\n", 179 acpi_power_state_string(state)); 180 return -ENODEV; 181 } 182 183 if (!device->power.flags.ignore_parent && 184 device->parent && (state < device->parent->power.state)) { 185 dev_warn(&device->dev, 186 "Cannot transition to power state %s for parent in %s\n", 187 acpi_power_state_string(state), 188 acpi_power_state_string(device->parent->power.state)); 189 return -ENODEV; 190 } 191 192 /* 193 * Transition Power 194 * ---------------- 195 * In accordance with ACPI 6, _PSx is executed before manipulating power 196 * resources, unless the target state is D0, in which case _PS0 is 197 * supposed to be executed after turning the power resources on. 198 */ 199 if (state > ACPI_STATE_D0) { 200 /* 201 * According to ACPI 6, devices cannot go from lower-power 202 * (deeper) states to higher-power (shallower) states. 203 */ 204 if (state < device->power.state) { 205 dev_warn(&device->dev, "Cannot transition from %s to %s\n", 206 acpi_power_state_string(device->power.state), 207 acpi_power_state_string(state)); 208 return -ENODEV; 209 } 210 211 result = acpi_dev_pm_explicit_set(device, state); 212 if (result) 213 goto end; 214 215 if (device->power.flags.power_resources) 216 result = acpi_power_transition(device, target_state); 217 } else { 218 if (device->power.flags.power_resources) { 219 result = acpi_power_transition(device, ACPI_STATE_D0); 220 if (result) 221 goto end; 222 } 223 result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0); 224 } 225 226 end: 227 if (result) { 228 dev_warn(&device->dev, "Failed to change power state to %s\n", 229 acpi_power_state_string(state)); 230 } else { 231 device->power.state = target_state; 232 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 233 "Device [%s] transitioned to %s\n", 234 device->pnp.bus_id, 235 acpi_power_state_string(state))); 236 } 237 238 return result; 239 } 240 EXPORT_SYMBOL(acpi_device_set_power); 241 242 int acpi_bus_set_power(acpi_handle handle, int state) 243 { 244 struct acpi_device *device; 245 int result; 246 247 result = acpi_bus_get_device(handle, &device); 248 if (result) 249 return result; 250 251 return acpi_device_set_power(device, state); 252 } 253 EXPORT_SYMBOL(acpi_bus_set_power); 254 255 int acpi_bus_init_power(struct acpi_device *device) 256 { 257 int state; 258 int result; 259 260 if (!device) 261 return -EINVAL; 262 263 device->power.state = ACPI_STATE_UNKNOWN; 264 if (!acpi_device_is_present(device)) 265 return -ENXIO; 266 267 result = acpi_device_get_power(device, &state); 268 if (result) 269 return result; 270 271 if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) { 272 /* Reference count the power resources. */ 273 result = acpi_power_on_resources(device, state); 274 if (result) 275 return result; 276 277 if (state == ACPI_STATE_D0) { 278 /* 279 * If _PSC is not present and the state inferred from 280 * power resources appears to be D0, it still may be 281 * necessary to execute _PS0 at this point, because 282 * another device using the same power resources may 283 * have been put into D0 previously and that's why we 284 * see D0 here. 285 */ 286 result = acpi_dev_pm_explicit_set(device, state); 287 if (result) 288 return result; 289 } 290 } else if (state == ACPI_STATE_UNKNOWN) { 291 /* 292 * No power resources and missing _PSC? Cross fingers and make 293 * it D0 in hope that this is what the BIOS put the device into. 294 * [We tried to force D0 here by executing _PS0, but that broke 295 * Toshiba P870-303 in a nasty way.] 296 */ 297 state = ACPI_STATE_D0; 298 } 299 device->power.state = state; 300 return 0; 301 } 302 303 /** 304 * acpi_device_fix_up_power - Force device with missing _PSC into D0. 305 * @device: Device object whose power state is to be fixed up. 306 * 307 * Devices without power resources and _PSC, but having _PS0 and _PS3 defined, 308 * are assumed to be put into D0 by the BIOS. However, in some cases that may 309 * not be the case and this function should be used then. 310 */ 311 int acpi_device_fix_up_power(struct acpi_device *device) 312 { 313 int ret = 0; 314 315 if (!device->power.flags.power_resources 316 && !device->power.flags.explicit_get 317 && device->power.state == ACPI_STATE_D0) 318 ret = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0); 319 320 return ret; 321 } 322 323 int acpi_device_update_power(struct acpi_device *device, int *state_p) 324 { 325 int state; 326 int result; 327 328 if (device->power.state == ACPI_STATE_UNKNOWN) { 329 result = acpi_bus_init_power(device); 330 if (!result && state_p) 331 *state_p = device->power.state; 332 333 return result; 334 } 335 336 result = acpi_device_get_power(device, &state); 337 if (result) 338 return result; 339 340 if (state == ACPI_STATE_UNKNOWN) { 341 state = ACPI_STATE_D0; 342 result = acpi_device_set_power(device, state); 343 if (result) 344 return result; 345 } else { 346 if (device->power.flags.power_resources) { 347 /* 348 * We don't need to really switch the state, bu we need 349 * to update the power resources' reference counters. 350 */ 351 result = acpi_power_transition(device, state); 352 if (result) 353 return result; 354 } 355 device->power.state = state; 356 } 357 if (state_p) 358 *state_p = state; 359 360 return 0; 361 } 362 EXPORT_SYMBOL_GPL(acpi_device_update_power); 363 364 int acpi_bus_update_power(acpi_handle handle, int *state_p) 365 { 366 struct acpi_device *device; 367 int result; 368 369 result = acpi_bus_get_device(handle, &device); 370 return result ? result : acpi_device_update_power(device, state_p); 371 } 372 EXPORT_SYMBOL_GPL(acpi_bus_update_power); 373 374 bool acpi_bus_power_manageable(acpi_handle handle) 375 { 376 struct acpi_device *device; 377 int result; 378 379 result = acpi_bus_get_device(handle, &device); 380 return result ? false : device->flags.power_manageable; 381 } 382 EXPORT_SYMBOL(acpi_bus_power_manageable); 383 384 #ifdef CONFIG_PM 385 static DEFINE_MUTEX(acpi_pm_notifier_lock); 386 387 static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used) 388 { 389 struct acpi_device *adev; 390 391 if (val != ACPI_NOTIFY_DEVICE_WAKE) 392 return; 393 394 adev = acpi_bus_get_acpi_device(handle); 395 if (!adev) 396 return; 397 398 mutex_lock(&acpi_pm_notifier_lock); 399 400 if (adev->wakeup.flags.notifier_present) { 401 __pm_wakeup_event(adev->wakeup.ws, 0); 402 if (adev->wakeup.context.work.func) 403 queue_pm_work(&adev->wakeup.context.work); 404 } 405 406 mutex_unlock(&acpi_pm_notifier_lock); 407 408 acpi_bus_put_acpi_device(adev); 409 } 410 411 /** 412 * acpi_add_pm_notifier - Register PM notify handler for given ACPI device. 413 * @adev: ACPI device to add the notify handler for. 414 * @dev: Device to generate a wakeup event for while handling the notification. 415 * @work_func: Work function to execute when handling the notification. 416 * 417 * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of 418 * PM wakeup events. For example, wakeup events may be generated for bridges 419 * if one of the devices below the bridge is signaling wakeup, even if the 420 * bridge itself doesn't have a wakeup GPE associated with it. 421 */ 422 acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev, 423 void (*work_func)(struct work_struct *work)) 424 { 425 acpi_status status = AE_ALREADY_EXISTS; 426 427 if (!dev && !work_func) 428 return AE_BAD_PARAMETER; 429 430 mutex_lock(&acpi_pm_notifier_lock); 431 432 if (adev->wakeup.flags.notifier_present) 433 goto out; 434 435 adev->wakeup.ws = wakeup_source_register(dev_name(&adev->dev)); 436 adev->wakeup.context.dev = dev; 437 if (work_func) 438 INIT_WORK(&adev->wakeup.context.work, work_func); 439 440 status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY, 441 acpi_pm_notify_handler, NULL); 442 if (ACPI_FAILURE(status)) 443 goto out; 444 445 adev->wakeup.flags.notifier_present = true; 446 447 out: 448 mutex_unlock(&acpi_pm_notifier_lock); 449 return status; 450 } 451 452 /** 453 * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device. 454 * @adev: ACPI device to remove the notifier from. 455 */ 456 acpi_status acpi_remove_pm_notifier(struct acpi_device *adev) 457 { 458 acpi_status status = AE_BAD_PARAMETER; 459 460 mutex_lock(&acpi_pm_notifier_lock); 461 462 if (!adev->wakeup.flags.notifier_present) 463 goto out; 464 465 status = acpi_remove_notify_handler(adev->handle, 466 ACPI_SYSTEM_NOTIFY, 467 acpi_pm_notify_handler); 468 if (ACPI_FAILURE(status)) 469 goto out; 470 471 if (adev->wakeup.context.work.func) { 472 cancel_work_sync(&adev->wakeup.context.work); 473 adev->wakeup.context.work.func = NULL; 474 } 475 adev->wakeup.context.dev = NULL; 476 wakeup_source_unregister(adev->wakeup.ws); 477 478 adev->wakeup.flags.notifier_present = false; 479 480 out: 481 mutex_unlock(&acpi_pm_notifier_lock); 482 return status; 483 } 484 485 bool acpi_bus_can_wakeup(acpi_handle handle) 486 { 487 struct acpi_device *device; 488 int result; 489 490 result = acpi_bus_get_device(handle, &device); 491 return result ? false : device->wakeup.flags.valid; 492 } 493 EXPORT_SYMBOL(acpi_bus_can_wakeup); 494 495 /** 496 * acpi_dev_pm_get_state - Get preferred power state of ACPI device. 497 * @dev: Device whose preferred target power state to return. 498 * @adev: ACPI device node corresponding to @dev. 499 * @target_state: System state to match the resultant device state. 500 * @d_min_p: Location to store the highest power state available to the device. 501 * @d_max_p: Location to store the lowest power state available to the device. 502 * 503 * Find the lowest power (highest number) and highest power (lowest number) ACPI 504 * device power states that the device can be in while the system is in the 505 * state represented by @target_state. Store the integer numbers representing 506 * those stats in the memory locations pointed to by @d_max_p and @d_min_p, 507 * respectively. 508 * 509 * Callers must ensure that @dev and @adev are valid pointers and that @adev 510 * actually corresponds to @dev before using this function. 511 * 512 * Returns 0 on success or -ENODATA when one of the ACPI methods fails or 513 * returns a value that doesn't make sense. The memory locations pointed to by 514 * @d_max_p and @d_min_p are only modified on success. 515 */ 516 static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev, 517 u32 target_state, int *d_min_p, int *d_max_p) 518 { 519 char method[] = { '_', 'S', '0' + target_state, 'D', '\0' }; 520 acpi_handle handle = adev->handle; 521 unsigned long long ret; 522 int d_min, d_max; 523 bool wakeup = false; 524 acpi_status status; 525 526 /* 527 * If the system state is S0, the lowest power state the device can be 528 * in is D3cold, unless the device has _S0W and is supposed to signal 529 * wakeup, in which case the return value of _S0W has to be used as the 530 * lowest power state available to the device. 531 */ 532 d_min = ACPI_STATE_D0; 533 d_max = ACPI_STATE_D3_COLD; 534 535 /* 536 * If present, _SxD methods return the minimum D-state (highest power 537 * state) we can use for the corresponding S-states. Otherwise, the 538 * minimum D-state is D0 (ACPI 3.x). 539 */ 540 if (target_state > ACPI_STATE_S0) { 541 /* 542 * We rely on acpi_evaluate_integer() not clobbering the integer 543 * provided if AE_NOT_FOUND is returned. 544 */ 545 ret = d_min; 546 status = acpi_evaluate_integer(handle, method, NULL, &ret); 547 if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND) 548 || ret > ACPI_STATE_D3_COLD) 549 return -ENODATA; 550 551 /* 552 * We need to handle legacy systems where D3hot and D3cold are 553 * the same and 3 is returned in both cases, so fall back to 554 * D3cold if D3hot is not a valid state. 555 */ 556 if (!adev->power.states[ret].flags.valid) { 557 if (ret == ACPI_STATE_D3_HOT) 558 ret = ACPI_STATE_D3_COLD; 559 else 560 return -ENODATA; 561 } 562 d_min = ret; 563 wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid 564 && adev->wakeup.sleep_state >= target_state; 565 } else if (dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) != 566 PM_QOS_FLAGS_NONE) { 567 wakeup = adev->wakeup.flags.valid; 568 } 569 570 /* 571 * If _PRW says we can wake up the system from the target sleep state, 572 * the D-state returned by _SxD is sufficient for that (we assume a 573 * wakeup-aware driver if wake is set). Still, if _SxW exists 574 * (ACPI 3.x), it should return the maximum (lowest power) D-state that 575 * can wake the system. _S0W may be valid, too. 576 */ 577 if (wakeup) { 578 method[3] = 'W'; 579 status = acpi_evaluate_integer(handle, method, NULL, &ret); 580 if (status == AE_NOT_FOUND) { 581 if (target_state > ACPI_STATE_S0) 582 d_max = d_min; 583 } else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) { 584 /* Fall back to D3cold if ret is not a valid state. */ 585 if (!adev->power.states[ret].flags.valid) 586 ret = ACPI_STATE_D3_COLD; 587 588 d_max = ret > d_min ? ret : d_min; 589 } else { 590 return -ENODATA; 591 } 592 } 593 594 if (d_min_p) 595 *d_min_p = d_min; 596 597 if (d_max_p) 598 *d_max_p = d_max; 599 600 return 0; 601 } 602 603 /** 604 * acpi_pm_device_sleep_state - Get preferred power state of ACPI device. 605 * @dev: Device whose preferred target power state to return. 606 * @d_min_p: Location to store the upper limit of the allowed states range. 607 * @d_max_in: Deepest low-power state to take into consideration. 608 * Return value: Preferred power state of the device on success, -ENODEV 609 * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is 610 * incorrect, or -ENODATA on ACPI method failure. 611 * 612 * The caller must ensure that @dev is valid before using this function. 613 */ 614 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in) 615 { 616 struct acpi_device *adev; 617 int ret, d_min, d_max; 618 619 if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD) 620 return -EINVAL; 621 622 if (d_max_in > ACPI_STATE_D2) { 623 enum pm_qos_flags_status stat; 624 625 stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF); 626 if (stat == PM_QOS_FLAGS_ALL) 627 d_max_in = ACPI_STATE_D2; 628 } 629 630 adev = ACPI_COMPANION(dev); 631 if (!adev) { 632 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__); 633 return -ENODEV; 634 } 635 636 ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(), 637 &d_min, &d_max); 638 if (ret) 639 return ret; 640 641 if (d_max_in < d_min) 642 return -EINVAL; 643 644 if (d_max > d_max_in) { 645 for (d_max = d_max_in; d_max > d_min; d_max--) { 646 if (adev->power.states[d_max].flags.valid) 647 break; 648 } 649 } 650 651 if (d_min_p) 652 *d_min_p = d_min; 653 654 return d_max; 655 } 656 EXPORT_SYMBOL(acpi_pm_device_sleep_state); 657 658 /** 659 * acpi_pm_notify_work_func - ACPI devices wakeup notification work function. 660 * @work: Work item to handle. 661 */ 662 static void acpi_pm_notify_work_func(struct work_struct *work) 663 { 664 struct device *dev; 665 666 dev = container_of(work, struct acpi_device_wakeup_context, work)->dev; 667 if (dev) { 668 pm_wakeup_event(dev, 0); 669 pm_runtime_resume(dev); 670 } 671 } 672 673 /** 674 * acpi_device_wakeup - Enable/disable wakeup functionality for device. 675 * @adev: ACPI device to enable/disable wakeup functionality for. 676 * @target_state: State the system is transitioning into. 677 * @enable: Whether to enable or disable the wakeup functionality. 678 * 679 * Enable/disable the GPE associated with @adev so that it can generate 680 * wakeup signals for the device in response to external (remote) events and 681 * enable/disable device wakeup power. 682 * 683 * Callers must ensure that @adev is a valid ACPI device node before executing 684 * this function. 685 */ 686 static int acpi_device_wakeup(struct acpi_device *adev, u32 target_state, 687 bool enable) 688 { 689 struct acpi_device_wakeup *wakeup = &adev->wakeup; 690 691 if (enable) { 692 acpi_status res; 693 int error; 694 695 error = acpi_enable_wakeup_device_power(adev, target_state); 696 if (error) 697 return error; 698 699 if (adev->wakeup.flags.enabled) 700 return 0; 701 702 res = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number); 703 if (ACPI_SUCCESS(res)) { 704 adev->wakeup.flags.enabled = 1; 705 } else { 706 acpi_disable_wakeup_device_power(adev); 707 return -EIO; 708 } 709 } else { 710 if (adev->wakeup.flags.enabled) { 711 acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number); 712 adev->wakeup.flags.enabled = 0; 713 } 714 acpi_disable_wakeup_device_power(adev); 715 } 716 return 0; 717 } 718 719 /** 720 * acpi_pm_device_run_wake - Enable/disable remote wakeup for given device. 721 * @dev: Device to enable/disable the platform to wake up. 722 * @enable: Whether to enable or disable the wakeup functionality. 723 */ 724 int acpi_pm_device_run_wake(struct device *phys_dev, bool enable) 725 { 726 struct acpi_device *adev; 727 728 if (!device_run_wake(phys_dev)) 729 return -EINVAL; 730 731 adev = ACPI_COMPANION(phys_dev); 732 if (!adev) { 733 dev_dbg(phys_dev, "ACPI companion missing in %s!\n", __func__); 734 return -ENODEV; 735 } 736 737 return acpi_device_wakeup(adev, ACPI_STATE_S0, enable); 738 } 739 EXPORT_SYMBOL(acpi_pm_device_run_wake); 740 741 #ifdef CONFIG_PM_SLEEP 742 /** 743 * acpi_pm_device_sleep_wake - Enable or disable device to wake up the system. 744 * @dev: Device to enable/desible to wake up the system from sleep states. 745 * @enable: Whether to enable or disable @dev to wake up the system. 746 */ 747 int acpi_pm_device_sleep_wake(struct device *dev, bool enable) 748 { 749 struct acpi_device *adev; 750 int error; 751 752 if (!device_can_wakeup(dev)) 753 return -EINVAL; 754 755 adev = ACPI_COMPANION(dev); 756 if (!adev) { 757 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__); 758 return -ENODEV; 759 } 760 761 error = acpi_device_wakeup(adev, acpi_target_system_state(), enable); 762 if (!error) 763 dev_info(dev, "System wakeup %s by ACPI\n", 764 enable ? "enabled" : "disabled"); 765 766 return error; 767 } 768 #endif /* CONFIG_PM_SLEEP */ 769 770 /** 771 * acpi_dev_pm_low_power - Put ACPI device into a low-power state. 772 * @dev: Device to put into a low-power state. 773 * @adev: ACPI device node corresponding to @dev. 774 * @system_state: System state to choose the device state for. 775 */ 776 static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev, 777 u32 system_state) 778 { 779 int ret, state; 780 781 if (!acpi_device_power_manageable(adev)) 782 return 0; 783 784 ret = acpi_dev_pm_get_state(dev, adev, system_state, NULL, &state); 785 return ret ? ret : acpi_device_set_power(adev, state); 786 } 787 788 /** 789 * acpi_dev_pm_full_power - Put ACPI device into the full-power state. 790 * @adev: ACPI device node to put into the full-power state. 791 */ 792 static int acpi_dev_pm_full_power(struct acpi_device *adev) 793 { 794 return acpi_device_power_manageable(adev) ? 795 acpi_device_set_power(adev, ACPI_STATE_D0) : 0; 796 } 797 798 /** 799 * acpi_dev_runtime_suspend - Put device into a low-power state using ACPI. 800 * @dev: Device to put into a low-power state. 801 * 802 * Put the given device into a runtime low-power state using the standard ACPI 803 * mechanism. Set up remote wakeup if desired, choose the state to put the 804 * device into (this checks if remote wakeup is expected to work too), and set 805 * the power state of the device. 806 */ 807 int acpi_dev_runtime_suspend(struct device *dev) 808 { 809 struct acpi_device *adev = ACPI_COMPANION(dev); 810 bool remote_wakeup; 811 int error; 812 813 if (!adev) 814 return 0; 815 816 remote_wakeup = dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) > 817 PM_QOS_FLAGS_NONE; 818 error = acpi_device_wakeup(adev, ACPI_STATE_S0, remote_wakeup); 819 if (remote_wakeup && error) 820 return -EAGAIN; 821 822 error = acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0); 823 if (error) 824 acpi_device_wakeup(adev, ACPI_STATE_S0, false); 825 826 return error; 827 } 828 EXPORT_SYMBOL_GPL(acpi_dev_runtime_suspend); 829 830 /** 831 * acpi_dev_runtime_resume - Put device into the full-power state using ACPI. 832 * @dev: Device to put into the full-power state. 833 * 834 * Put the given device into the full-power state using the standard ACPI 835 * mechanism at run time. Set the power state of the device to ACPI D0 and 836 * disable remote wakeup. 837 */ 838 int acpi_dev_runtime_resume(struct device *dev) 839 { 840 struct acpi_device *adev = ACPI_COMPANION(dev); 841 int error; 842 843 if (!adev) 844 return 0; 845 846 error = acpi_dev_pm_full_power(adev); 847 acpi_device_wakeup(adev, ACPI_STATE_S0, false); 848 return error; 849 } 850 EXPORT_SYMBOL_GPL(acpi_dev_runtime_resume); 851 852 /** 853 * acpi_subsys_runtime_suspend - Suspend device using ACPI. 854 * @dev: Device to suspend. 855 * 856 * Carry out the generic runtime suspend procedure for @dev and use ACPI to put 857 * it into a runtime low-power state. 858 */ 859 int acpi_subsys_runtime_suspend(struct device *dev) 860 { 861 int ret = pm_generic_runtime_suspend(dev); 862 return ret ? ret : acpi_dev_runtime_suspend(dev); 863 } 864 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend); 865 866 /** 867 * acpi_subsys_runtime_resume - Resume device using ACPI. 868 * @dev: Device to Resume. 869 * 870 * Use ACPI to put the given device into the full-power state and carry out the 871 * generic runtime resume procedure for it. 872 */ 873 int acpi_subsys_runtime_resume(struct device *dev) 874 { 875 int ret = acpi_dev_runtime_resume(dev); 876 return ret ? ret : pm_generic_runtime_resume(dev); 877 } 878 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume); 879 880 #ifdef CONFIG_PM_SLEEP 881 /** 882 * acpi_dev_suspend_late - Put device into a low-power state using ACPI. 883 * @dev: Device to put into a low-power state. 884 * 885 * Put the given device into a low-power state during system transition to a 886 * sleep state using the standard ACPI mechanism. Set up system wakeup if 887 * desired, choose the state to put the device into (this checks if system 888 * wakeup is expected to work too), and set the power state of the device. 889 */ 890 int acpi_dev_suspend_late(struct device *dev) 891 { 892 struct acpi_device *adev = ACPI_COMPANION(dev); 893 u32 target_state; 894 bool wakeup; 895 int error; 896 897 if (!adev) 898 return 0; 899 900 target_state = acpi_target_system_state(); 901 wakeup = device_may_wakeup(dev) && acpi_device_can_wakeup(adev); 902 error = acpi_device_wakeup(adev, target_state, wakeup); 903 if (wakeup && error) 904 return error; 905 906 error = acpi_dev_pm_low_power(dev, adev, target_state); 907 if (error) 908 acpi_device_wakeup(adev, ACPI_STATE_UNKNOWN, false); 909 910 return error; 911 } 912 EXPORT_SYMBOL_GPL(acpi_dev_suspend_late); 913 914 /** 915 * acpi_dev_resume_early - Put device into the full-power state using ACPI. 916 * @dev: Device to put into the full-power state. 917 * 918 * Put the given device into the full-power state using the standard ACPI 919 * mechanism during system transition to the working state. Set the power 920 * state of the device to ACPI D0 and disable remote wakeup. 921 */ 922 int acpi_dev_resume_early(struct device *dev) 923 { 924 struct acpi_device *adev = ACPI_COMPANION(dev); 925 int error; 926 927 if (!adev) 928 return 0; 929 930 error = acpi_dev_pm_full_power(adev); 931 acpi_device_wakeup(adev, ACPI_STATE_UNKNOWN, false); 932 return error; 933 } 934 EXPORT_SYMBOL_GPL(acpi_dev_resume_early); 935 936 /** 937 * acpi_subsys_prepare - Prepare device for system transition to a sleep state. 938 * @dev: Device to prepare. 939 */ 940 int acpi_subsys_prepare(struct device *dev) 941 { 942 struct acpi_device *adev = ACPI_COMPANION(dev); 943 u32 sys_target; 944 int ret, state; 945 946 ret = pm_generic_prepare(dev); 947 if (ret < 0) 948 return ret; 949 950 if (!adev || !pm_runtime_suspended(dev) 951 || device_may_wakeup(dev) != !!adev->wakeup.prepare_count) 952 return 0; 953 954 sys_target = acpi_target_system_state(); 955 if (sys_target == ACPI_STATE_S0) 956 return 1; 957 958 if (adev->power.flags.dsw_present) 959 return 0; 960 961 ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state); 962 return !ret && state == adev->power.state; 963 } 964 EXPORT_SYMBOL_GPL(acpi_subsys_prepare); 965 966 /** 967 * acpi_subsys_suspend - Run the device driver's suspend callback. 968 * @dev: Device to handle. 969 * 970 * Follow PCI and resume devices suspended at run time before running their 971 * system suspend callbacks. 972 */ 973 int acpi_subsys_suspend(struct device *dev) 974 { 975 pm_runtime_resume(dev); 976 return pm_generic_suspend(dev); 977 } 978 EXPORT_SYMBOL_GPL(acpi_subsys_suspend); 979 980 /** 981 * acpi_subsys_suspend_late - Suspend device using ACPI. 982 * @dev: Device to suspend. 983 * 984 * Carry out the generic late suspend procedure for @dev and use ACPI to put 985 * it into a low-power state during system transition into a sleep state. 986 */ 987 int acpi_subsys_suspend_late(struct device *dev) 988 { 989 int ret = pm_generic_suspend_late(dev); 990 return ret ? ret : acpi_dev_suspend_late(dev); 991 } 992 EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late); 993 994 /** 995 * acpi_subsys_resume_early - Resume device using ACPI. 996 * @dev: Device to Resume. 997 * 998 * Use ACPI to put the given device into the full-power state and carry out the 999 * generic early resume procedure for it during system transition into the 1000 * working state. 1001 */ 1002 int acpi_subsys_resume_early(struct device *dev) 1003 { 1004 int ret = acpi_dev_resume_early(dev); 1005 return ret ? ret : pm_generic_resume_early(dev); 1006 } 1007 EXPORT_SYMBOL_GPL(acpi_subsys_resume_early); 1008 1009 /** 1010 * acpi_subsys_freeze - Run the device driver's freeze callback. 1011 * @dev: Device to handle. 1012 */ 1013 int acpi_subsys_freeze(struct device *dev) 1014 { 1015 /* 1016 * This used to be done in acpi_subsys_prepare() for all devices and 1017 * some drivers may depend on it, so do it here. Ideally, however, 1018 * runtime-suspended devices should not be touched during freeze/thaw 1019 * transitions. 1020 */ 1021 pm_runtime_resume(dev); 1022 return pm_generic_freeze(dev); 1023 } 1024 EXPORT_SYMBOL_GPL(acpi_subsys_freeze); 1025 1026 #endif /* CONFIG_PM_SLEEP */ 1027 1028 static struct dev_pm_domain acpi_general_pm_domain = { 1029 .ops = { 1030 .runtime_suspend = acpi_subsys_runtime_suspend, 1031 .runtime_resume = acpi_subsys_runtime_resume, 1032 #ifdef CONFIG_PM_SLEEP 1033 .prepare = acpi_subsys_prepare, 1034 .complete = pm_complete_with_resume_check, 1035 .suspend = acpi_subsys_suspend, 1036 .suspend_late = acpi_subsys_suspend_late, 1037 .resume_early = acpi_subsys_resume_early, 1038 .freeze = acpi_subsys_freeze, 1039 .poweroff = acpi_subsys_suspend, 1040 .poweroff_late = acpi_subsys_suspend_late, 1041 .restore_early = acpi_subsys_resume_early, 1042 #endif 1043 }, 1044 }; 1045 1046 /** 1047 * acpi_dev_pm_detach - Remove ACPI power management from the device. 1048 * @dev: Device to take care of. 1049 * @power_off: Whether or not to try to remove power from the device. 1050 * 1051 * Remove the device from the general ACPI PM domain and remove its wakeup 1052 * notifier. If @power_off is set, additionally remove power from the device if 1053 * possible. 1054 * 1055 * Callers must ensure proper synchronization of this function with power 1056 * management callbacks. 1057 */ 1058 static void acpi_dev_pm_detach(struct device *dev, bool power_off) 1059 { 1060 struct acpi_device *adev = ACPI_COMPANION(dev); 1061 1062 if (adev && dev->pm_domain == &acpi_general_pm_domain) { 1063 dev_pm_domain_set(dev, NULL); 1064 acpi_remove_pm_notifier(adev); 1065 if (power_off) { 1066 /* 1067 * If the device's PM QoS resume latency limit or flags 1068 * have been exposed to user space, they have to be 1069 * hidden at this point, so that they don't affect the 1070 * choice of the low-power state to put the device into. 1071 */ 1072 dev_pm_qos_hide_latency_limit(dev); 1073 dev_pm_qos_hide_flags(dev); 1074 acpi_device_wakeup(adev, ACPI_STATE_S0, false); 1075 acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0); 1076 } 1077 } 1078 } 1079 1080 /** 1081 * acpi_dev_pm_attach - Prepare device for ACPI power management. 1082 * @dev: Device to prepare. 1083 * @power_on: Whether or not to power on the device. 1084 * 1085 * If @dev has a valid ACPI handle that has a valid struct acpi_device object 1086 * attached to it, install a wakeup notification handler for the device and 1087 * add it to the general ACPI PM domain. If @power_on is set, the device will 1088 * be put into the ACPI D0 state before the function returns. 1089 * 1090 * This assumes that the @dev's bus type uses generic power management callbacks 1091 * (or doesn't use any power management callbacks at all). 1092 * 1093 * Callers must ensure proper synchronization of this function with power 1094 * management callbacks. 1095 */ 1096 int acpi_dev_pm_attach(struct device *dev, bool power_on) 1097 { 1098 struct acpi_device *adev = ACPI_COMPANION(dev); 1099 1100 if (!adev) 1101 return -ENODEV; 1102 1103 if (dev->pm_domain) 1104 return -EEXIST; 1105 1106 /* 1107 * Only attach the power domain to the first device if the 1108 * companion is shared by multiple. This is to prevent doing power 1109 * management twice. 1110 */ 1111 if (!acpi_device_is_first_physical_node(adev, dev)) 1112 return -EBUSY; 1113 1114 acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func); 1115 dev_pm_domain_set(dev, &acpi_general_pm_domain); 1116 if (power_on) { 1117 acpi_dev_pm_full_power(adev); 1118 acpi_device_wakeup(adev, ACPI_STATE_S0, false); 1119 } 1120 1121 dev->pm_domain->detach = acpi_dev_pm_detach; 1122 return 0; 1123 } 1124 EXPORT_SYMBOL_GPL(acpi_dev_pm_attach); 1125 #endif /* CONFIG_PM */ 1126