1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * drivers/acpi/device_pm.c - ACPI device power management routines. 4 * 5 * Copyright (C) 2012, Intel Corp. 6 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 7 * 8 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 9 * 10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 11 */ 12 13 #include <linux/acpi.h> 14 #include <linux/export.h> 15 #include <linux/mutex.h> 16 #include <linux/pm_qos.h> 17 #include <linux/pm_domain.h> 18 #include <linux/pm_runtime.h> 19 #include <linux/suspend.h> 20 21 #include "internal.h" 22 23 #define _COMPONENT ACPI_POWER_COMPONENT 24 ACPI_MODULE_NAME("device_pm"); 25 26 /** 27 * acpi_power_state_string - String representation of ACPI device power state. 28 * @state: ACPI device power state to return the string representation of. 29 */ 30 const char *acpi_power_state_string(int state) 31 { 32 switch (state) { 33 case ACPI_STATE_D0: 34 return "D0"; 35 case ACPI_STATE_D1: 36 return "D1"; 37 case ACPI_STATE_D2: 38 return "D2"; 39 case ACPI_STATE_D3_HOT: 40 return "D3hot"; 41 case ACPI_STATE_D3_COLD: 42 return "D3cold"; 43 default: 44 return "(unknown)"; 45 } 46 } 47 48 static int acpi_dev_pm_explicit_get(struct acpi_device *device, int *state) 49 { 50 unsigned long long psc; 51 acpi_status status; 52 53 status = acpi_evaluate_integer(device->handle, "_PSC", NULL, &psc); 54 if (ACPI_FAILURE(status)) 55 return -ENODEV; 56 57 *state = psc; 58 return 0; 59 } 60 61 /** 62 * acpi_device_get_power - Get power state of an ACPI device. 63 * @device: Device to get the power state of. 64 * @state: Place to store the power state of the device. 65 * 66 * This function does not update the device's power.state field, but it may 67 * update its parent's power.state field (when the parent's power state is 68 * unknown and the device's power state turns out to be D0). 69 * 70 * Also, it does not update power resource reference counters to ensure that 71 * the power state returned by it will be persistent and it may return a power 72 * state shallower than previously set by acpi_device_set_power() for @device 73 * (if that power state depends on any power resources). 74 */ 75 int acpi_device_get_power(struct acpi_device *device, int *state) 76 { 77 int result = ACPI_STATE_UNKNOWN; 78 int error; 79 80 if (!device || !state) 81 return -EINVAL; 82 83 if (!device->flags.power_manageable) { 84 /* TBD: Non-recursive algorithm for walking up hierarchy. */ 85 *state = device->parent ? 86 device->parent->power.state : ACPI_STATE_D0; 87 goto out; 88 } 89 90 /* 91 * Get the device's power state from power resources settings and _PSC, 92 * if available. 93 */ 94 if (device->power.flags.power_resources) { 95 error = acpi_power_get_inferred_state(device, &result); 96 if (error) 97 return error; 98 } 99 if (device->power.flags.explicit_get) { 100 int psc; 101 102 error = acpi_dev_pm_explicit_get(device, &psc); 103 if (error) 104 return error; 105 106 /* 107 * The power resources settings may indicate a power state 108 * shallower than the actual power state of the device, because 109 * the same power resources may be referenced by other devices. 110 * 111 * For systems predating ACPI 4.0 we assume that D3hot is the 112 * deepest state that can be supported. 113 */ 114 if (psc > result && psc < ACPI_STATE_D3_COLD) 115 result = psc; 116 else if (result == ACPI_STATE_UNKNOWN) 117 result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_HOT : psc; 118 } 119 120 /* 121 * If we were unsure about the device parent's power state up to this 122 * point, the fact that the device is in D0 implies that the parent has 123 * to be in D0 too, except if ignore_parent is set. 124 */ 125 if (!device->power.flags.ignore_parent && device->parent 126 && device->parent->power.state == ACPI_STATE_UNKNOWN 127 && result == ACPI_STATE_D0) 128 device->parent->power.state = ACPI_STATE_D0; 129 130 *state = result; 131 132 out: 133 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n", 134 device->pnp.bus_id, acpi_power_state_string(*state))); 135 136 return 0; 137 } 138 139 static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state) 140 { 141 if (adev->power.states[state].flags.explicit_set) { 142 char method[5] = { '_', 'P', 'S', '0' + state, '\0' }; 143 acpi_status status; 144 145 status = acpi_evaluate_object(adev->handle, method, NULL, NULL); 146 if (ACPI_FAILURE(status)) 147 return -ENODEV; 148 } 149 return 0; 150 } 151 152 /** 153 * acpi_device_set_power - Set power state of an ACPI device. 154 * @device: Device to set the power state of. 155 * @state: New power state to set. 156 * 157 * Callers must ensure that the device is power manageable before using this 158 * function. 159 */ 160 int acpi_device_set_power(struct acpi_device *device, int state) 161 { 162 int target_state = state; 163 int result = 0; 164 165 if (!device || !device->flags.power_manageable 166 || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD)) 167 return -EINVAL; 168 169 acpi_handle_debug(device->handle, "Power state change: %s -> %s\n", 170 acpi_power_state_string(device->power.state), 171 acpi_power_state_string(state)); 172 173 /* Make sure this is a valid target state */ 174 175 /* There is a special case for D0 addressed below. */ 176 if (state > ACPI_STATE_D0 && state == device->power.state) { 177 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already in %s\n", 178 device->pnp.bus_id, 179 acpi_power_state_string(state))); 180 return 0; 181 } 182 183 if (state == ACPI_STATE_D3_COLD) { 184 /* 185 * For transitions to D3cold we need to execute _PS3 and then 186 * possibly drop references to the power resources in use. 187 */ 188 state = ACPI_STATE_D3_HOT; 189 /* If _PR3 is not available, use D3hot as the target state. */ 190 if (!device->power.states[ACPI_STATE_D3_COLD].flags.valid) 191 target_state = state; 192 } else if (!device->power.states[state].flags.valid) { 193 dev_warn(&device->dev, "Power state %s not supported\n", 194 acpi_power_state_string(state)); 195 return -ENODEV; 196 } 197 198 if (!device->power.flags.ignore_parent && 199 device->parent && (state < device->parent->power.state)) { 200 dev_warn(&device->dev, 201 "Cannot transition to power state %s for parent in %s\n", 202 acpi_power_state_string(state), 203 acpi_power_state_string(device->parent->power.state)); 204 return -ENODEV; 205 } 206 207 /* 208 * Transition Power 209 * ---------------- 210 * In accordance with ACPI 6, _PSx is executed before manipulating power 211 * resources, unless the target state is D0, in which case _PS0 is 212 * supposed to be executed after turning the power resources on. 213 */ 214 if (state > ACPI_STATE_D0) { 215 /* 216 * According to ACPI 6, devices cannot go from lower-power 217 * (deeper) states to higher-power (shallower) states. 218 */ 219 if (state < device->power.state) { 220 dev_warn(&device->dev, "Cannot transition from %s to %s\n", 221 acpi_power_state_string(device->power.state), 222 acpi_power_state_string(state)); 223 return -ENODEV; 224 } 225 226 /* 227 * If the device goes from D3hot to D3cold, _PS3 has been 228 * evaluated for it already, so skip it in that case. 229 */ 230 if (device->power.state < ACPI_STATE_D3_HOT) { 231 result = acpi_dev_pm_explicit_set(device, state); 232 if (result) 233 goto end; 234 } 235 236 if (device->power.flags.power_resources) 237 result = acpi_power_transition(device, target_state); 238 } else { 239 int cur_state = device->power.state; 240 241 if (device->power.flags.power_resources) { 242 result = acpi_power_transition(device, ACPI_STATE_D0); 243 if (result) 244 goto end; 245 } 246 247 if (cur_state == ACPI_STATE_D0) { 248 int psc; 249 250 /* Nothing to do here if _PSC is not present. */ 251 if (!device->power.flags.explicit_get) 252 return 0; 253 254 /* 255 * The power state of the device was set to D0 last 256 * time, but that might have happened before a 257 * system-wide transition involving the platform 258 * firmware, so it may be necessary to evaluate _PS0 259 * for the device here. However, use extra care here 260 * and evaluate _PSC to check the device's current power 261 * state, and only invoke _PS0 if the evaluation of _PSC 262 * is successful and it returns a power state different 263 * from D0. 264 */ 265 result = acpi_dev_pm_explicit_get(device, &psc); 266 if (result || psc == ACPI_STATE_D0) 267 return 0; 268 } 269 270 result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0); 271 } 272 273 end: 274 if (result) { 275 dev_warn(&device->dev, "Failed to change power state to %s\n", 276 acpi_power_state_string(state)); 277 } else { 278 device->power.state = target_state; 279 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 280 "Device [%s] transitioned to %s\n", 281 device->pnp.bus_id, 282 acpi_power_state_string(state))); 283 } 284 285 return result; 286 } 287 EXPORT_SYMBOL(acpi_device_set_power); 288 289 int acpi_bus_set_power(acpi_handle handle, int state) 290 { 291 struct acpi_device *device; 292 int result; 293 294 result = acpi_bus_get_device(handle, &device); 295 if (result) 296 return result; 297 298 return acpi_device_set_power(device, state); 299 } 300 EXPORT_SYMBOL(acpi_bus_set_power); 301 302 int acpi_bus_init_power(struct acpi_device *device) 303 { 304 int state; 305 int result; 306 307 if (!device) 308 return -EINVAL; 309 310 device->power.state = ACPI_STATE_UNKNOWN; 311 if (!acpi_device_is_present(device)) { 312 device->flags.initialized = false; 313 return -ENXIO; 314 } 315 316 result = acpi_device_get_power(device, &state); 317 if (result) 318 return result; 319 320 if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) { 321 /* Reference count the power resources. */ 322 result = acpi_power_on_resources(device, state); 323 if (result) 324 return result; 325 326 if (state == ACPI_STATE_D0) { 327 /* 328 * If _PSC is not present and the state inferred from 329 * power resources appears to be D0, it still may be 330 * necessary to execute _PS0 at this point, because 331 * another device using the same power resources may 332 * have been put into D0 previously and that's why we 333 * see D0 here. 334 */ 335 result = acpi_dev_pm_explicit_set(device, state); 336 if (result) 337 return result; 338 } 339 } else if (state == ACPI_STATE_UNKNOWN) { 340 /* 341 * No power resources and missing _PSC? Cross fingers and make 342 * it D0 in hope that this is what the BIOS put the device into. 343 * [We tried to force D0 here by executing _PS0, but that broke 344 * Toshiba P870-303 in a nasty way.] 345 */ 346 state = ACPI_STATE_D0; 347 } 348 device->power.state = state; 349 return 0; 350 } 351 352 /** 353 * acpi_device_fix_up_power - Force device with missing _PSC into D0. 354 * @device: Device object whose power state is to be fixed up. 355 * 356 * Devices without power resources and _PSC, but having _PS0 and _PS3 defined, 357 * are assumed to be put into D0 by the BIOS. However, in some cases that may 358 * not be the case and this function should be used then. 359 */ 360 int acpi_device_fix_up_power(struct acpi_device *device) 361 { 362 int ret = 0; 363 364 if (!device->power.flags.power_resources 365 && !device->power.flags.explicit_get 366 && device->power.state == ACPI_STATE_D0) 367 ret = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0); 368 369 return ret; 370 } 371 EXPORT_SYMBOL_GPL(acpi_device_fix_up_power); 372 373 int acpi_device_update_power(struct acpi_device *device, int *state_p) 374 { 375 int state; 376 int result; 377 378 if (device->power.state == ACPI_STATE_UNKNOWN) { 379 result = acpi_bus_init_power(device); 380 if (!result && state_p) 381 *state_p = device->power.state; 382 383 return result; 384 } 385 386 result = acpi_device_get_power(device, &state); 387 if (result) 388 return result; 389 390 if (state == ACPI_STATE_UNKNOWN) { 391 state = ACPI_STATE_D0; 392 result = acpi_device_set_power(device, state); 393 if (result) 394 return result; 395 } else { 396 if (device->power.flags.power_resources) { 397 /* 398 * We don't need to really switch the state, bu we need 399 * to update the power resources' reference counters. 400 */ 401 result = acpi_power_transition(device, state); 402 if (result) 403 return result; 404 } 405 device->power.state = state; 406 } 407 if (state_p) 408 *state_p = state; 409 410 return 0; 411 } 412 EXPORT_SYMBOL_GPL(acpi_device_update_power); 413 414 int acpi_bus_update_power(acpi_handle handle, int *state_p) 415 { 416 struct acpi_device *device; 417 int result; 418 419 result = acpi_bus_get_device(handle, &device); 420 return result ? result : acpi_device_update_power(device, state_p); 421 } 422 EXPORT_SYMBOL_GPL(acpi_bus_update_power); 423 424 bool acpi_bus_power_manageable(acpi_handle handle) 425 { 426 struct acpi_device *device; 427 int result; 428 429 result = acpi_bus_get_device(handle, &device); 430 return result ? false : device->flags.power_manageable; 431 } 432 EXPORT_SYMBOL(acpi_bus_power_manageable); 433 434 #ifdef CONFIG_PM 435 static DEFINE_MUTEX(acpi_pm_notifier_lock); 436 static DEFINE_MUTEX(acpi_pm_notifier_install_lock); 437 438 void acpi_pm_wakeup_event(struct device *dev) 439 { 440 pm_wakeup_dev_event(dev, 0, acpi_s2idle_wakeup()); 441 } 442 EXPORT_SYMBOL_GPL(acpi_pm_wakeup_event); 443 444 static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used) 445 { 446 struct acpi_device *adev; 447 448 if (val != ACPI_NOTIFY_DEVICE_WAKE) 449 return; 450 451 acpi_handle_debug(handle, "Wake notify\n"); 452 453 adev = acpi_bus_get_acpi_device(handle); 454 if (!adev) 455 return; 456 457 mutex_lock(&acpi_pm_notifier_lock); 458 459 if (adev->wakeup.flags.notifier_present) { 460 pm_wakeup_ws_event(adev->wakeup.ws, 0, acpi_s2idle_wakeup()); 461 if (adev->wakeup.context.func) { 462 acpi_handle_debug(handle, "Running %pS for %s\n", 463 adev->wakeup.context.func, 464 dev_name(adev->wakeup.context.dev)); 465 adev->wakeup.context.func(&adev->wakeup.context); 466 } 467 } 468 469 mutex_unlock(&acpi_pm_notifier_lock); 470 471 acpi_bus_put_acpi_device(adev); 472 } 473 474 /** 475 * acpi_add_pm_notifier - Register PM notify handler for given ACPI device. 476 * @adev: ACPI device to add the notify handler for. 477 * @dev: Device to generate a wakeup event for while handling the notification. 478 * @func: Work function to execute when handling the notification. 479 * 480 * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of 481 * PM wakeup events. For example, wakeup events may be generated for bridges 482 * if one of the devices below the bridge is signaling wakeup, even if the 483 * bridge itself doesn't have a wakeup GPE associated with it. 484 */ 485 acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev, 486 void (*func)(struct acpi_device_wakeup_context *context)) 487 { 488 acpi_status status = AE_ALREADY_EXISTS; 489 490 if (!dev && !func) 491 return AE_BAD_PARAMETER; 492 493 mutex_lock(&acpi_pm_notifier_install_lock); 494 495 if (adev->wakeup.flags.notifier_present) 496 goto out; 497 498 status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY, 499 acpi_pm_notify_handler, NULL); 500 if (ACPI_FAILURE(status)) 501 goto out; 502 503 mutex_lock(&acpi_pm_notifier_lock); 504 adev->wakeup.ws = wakeup_source_register(&adev->dev, 505 dev_name(&adev->dev)); 506 adev->wakeup.context.dev = dev; 507 adev->wakeup.context.func = func; 508 adev->wakeup.flags.notifier_present = true; 509 mutex_unlock(&acpi_pm_notifier_lock); 510 511 out: 512 mutex_unlock(&acpi_pm_notifier_install_lock); 513 return status; 514 } 515 516 /** 517 * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device. 518 * @adev: ACPI device to remove the notifier from. 519 */ 520 acpi_status acpi_remove_pm_notifier(struct acpi_device *adev) 521 { 522 acpi_status status = AE_BAD_PARAMETER; 523 524 mutex_lock(&acpi_pm_notifier_install_lock); 525 526 if (!adev->wakeup.flags.notifier_present) 527 goto out; 528 529 status = acpi_remove_notify_handler(adev->handle, 530 ACPI_SYSTEM_NOTIFY, 531 acpi_pm_notify_handler); 532 if (ACPI_FAILURE(status)) 533 goto out; 534 535 mutex_lock(&acpi_pm_notifier_lock); 536 adev->wakeup.context.func = NULL; 537 adev->wakeup.context.dev = NULL; 538 wakeup_source_unregister(adev->wakeup.ws); 539 adev->wakeup.flags.notifier_present = false; 540 mutex_unlock(&acpi_pm_notifier_lock); 541 542 out: 543 mutex_unlock(&acpi_pm_notifier_install_lock); 544 return status; 545 } 546 547 bool acpi_bus_can_wakeup(acpi_handle handle) 548 { 549 struct acpi_device *device; 550 int result; 551 552 result = acpi_bus_get_device(handle, &device); 553 return result ? false : device->wakeup.flags.valid; 554 } 555 EXPORT_SYMBOL(acpi_bus_can_wakeup); 556 557 bool acpi_pm_device_can_wakeup(struct device *dev) 558 { 559 struct acpi_device *adev = ACPI_COMPANION(dev); 560 561 return adev ? acpi_device_can_wakeup(adev) : false; 562 } 563 564 /** 565 * acpi_dev_pm_get_state - Get preferred power state of ACPI device. 566 * @dev: Device whose preferred target power state to return. 567 * @adev: ACPI device node corresponding to @dev. 568 * @target_state: System state to match the resultant device state. 569 * @d_min_p: Location to store the highest power state available to the device. 570 * @d_max_p: Location to store the lowest power state available to the device. 571 * 572 * Find the lowest power (highest number) and highest power (lowest number) ACPI 573 * device power states that the device can be in while the system is in the 574 * state represented by @target_state. Store the integer numbers representing 575 * those stats in the memory locations pointed to by @d_max_p and @d_min_p, 576 * respectively. 577 * 578 * Callers must ensure that @dev and @adev are valid pointers and that @adev 579 * actually corresponds to @dev before using this function. 580 * 581 * Returns 0 on success or -ENODATA when one of the ACPI methods fails or 582 * returns a value that doesn't make sense. The memory locations pointed to by 583 * @d_max_p and @d_min_p are only modified on success. 584 */ 585 static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev, 586 u32 target_state, int *d_min_p, int *d_max_p) 587 { 588 char method[] = { '_', 'S', '0' + target_state, 'D', '\0' }; 589 acpi_handle handle = adev->handle; 590 unsigned long long ret; 591 int d_min, d_max; 592 bool wakeup = false; 593 bool has_sxd = false; 594 acpi_status status; 595 596 /* 597 * If the system state is S0, the lowest power state the device can be 598 * in is D3cold, unless the device has _S0W and is supposed to signal 599 * wakeup, in which case the return value of _S0W has to be used as the 600 * lowest power state available to the device. 601 */ 602 d_min = ACPI_STATE_D0; 603 d_max = ACPI_STATE_D3_COLD; 604 605 /* 606 * If present, _SxD methods return the minimum D-state (highest power 607 * state) we can use for the corresponding S-states. Otherwise, the 608 * minimum D-state is D0 (ACPI 3.x). 609 */ 610 if (target_state > ACPI_STATE_S0) { 611 /* 612 * We rely on acpi_evaluate_integer() not clobbering the integer 613 * provided if AE_NOT_FOUND is returned. 614 */ 615 ret = d_min; 616 status = acpi_evaluate_integer(handle, method, NULL, &ret); 617 if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND) 618 || ret > ACPI_STATE_D3_COLD) 619 return -ENODATA; 620 621 /* 622 * We need to handle legacy systems where D3hot and D3cold are 623 * the same and 3 is returned in both cases, so fall back to 624 * D3cold if D3hot is not a valid state. 625 */ 626 if (!adev->power.states[ret].flags.valid) { 627 if (ret == ACPI_STATE_D3_HOT) 628 ret = ACPI_STATE_D3_COLD; 629 else 630 return -ENODATA; 631 } 632 633 if (status == AE_OK) 634 has_sxd = true; 635 636 d_min = ret; 637 wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid 638 && adev->wakeup.sleep_state >= target_state; 639 } else { 640 wakeup = adev->wakeup.flags.valid; 641 } 642 643 /* 644 * If _PRW says we can wake up the system from the target sleep state, 645 * the D-state returned by _SxD is sufficient for that (we assume a 646 * wakeup-aware driver if wake is set). Still, if _SxW exists 647 * (ACPI 3.x), it should return the maximum (lowest power) D-state that 648 * can wake the system. _S0W may be valid, too. 649 */ 650 if (wakeup) { 651 method[3] = 'W'; 652 status = acpi_evaluate_integer(handle, method, NULL, &ret); 653 if (status == AE_NOT_FOUND) { 654 /* No _SxW. In this case, the ACPI spec says that we 655 * must not go into any power state deeper than the 656 * value returned from _SxD. 657 */ 658 if (has_sxd && target_state > ACPI_STATE_S0) 659 d_max = d_min; 660 } else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) { 661 /* Fall back to D3cold if ret is not a valid state. */ 662 if (!adev->power.states[ret].flags.valid) 663 ret = ACPI_STATE_D3_COLD; 664 665 d_max = ret > d_min ? ret : d_min; 666 } else { 667 return -ENODATA; 668 } 669 } 670 671 if (d_min_p) 672 *d_min_p = d_min; 673 674 if (d_max_p) 675 *d_max_p = d_max; 676 677 return 0; 678 } 679 680 /** 681 * acpi_pm_device_sleep_state - Get preferred power state of ACPI device. 682 * @dev: Device whose preferred target power state to return. 683 * @d_min_p: Location to store the upper limit of the allowed states range. 684 * @d_max_in: Deepest low-power state to take into consideration. 685 * Return value: Preferred power state of the device on success, -ENODEV 686 * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is 687 * incorrect, or -ENODATA on ACPI method failure. 688 * 689 * The caller must ensure that @dev is valid before using this function. 690 */ 691 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in) 692 { 693 struct acpi_device *adev; 694 int ret, d_min, d_max; 695 696 if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD) 697 return -EINVAL; 698 699 if (d_max_in > ACPI_STATE_D2) { 700 enum pm_qos_flags_status stat; 701 702 stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF); 703 if (stat == PM_QOS_FLAGS_ALL) 704 d_max_in = ACPI_STATE_D2; 705 } 706 707 adev = ACPI_COMPANION(dev); 708 if (!adev) { 709 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__); 710 return -ENODEV; 711 } 712 713 ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(), 714 &d_min, &d_max); 715 if (ret) 716 return ret; 717 718 if (d_max_in < d_min) 719 return -EINVAL; 720 721 if (d_max > d_max_in) { 722 for (d_max = d_max_in; d_max > d_min; d_max--) { 723 if (adev->power.states[d_max].flags.valid) 724 break; 725 } 726 } 727 728 if (d_min_p) 729 *d_min_p = d_min; 730 731 return d_max; 732 } 733 EXPORT_SYMBOL(acpi_pm_device_sleep_state); 734 735 /** 736 * acpi_pm_notify_work_func - ACPI devices wakeup notification work function. 737 * @context: Device wakeup context. 738 */ 739 static void acpi_pm_notify_work_func(struct acpi_device_wakeup_context *context) 740 { 741 struct device *dev = context->dev; 742 743 if (dev) { 744 pm_wakeup_event(dev, 0); 745 pm_request_resume(dev); 746 } 747 } 748 749 static DEFINE_MUTEX(acpi_wakeup_lock); 750 751 static int __acpi_device_wakeup_enable(struct acpi_device *adev, 752 u32 target_state, int max_count) 753 { 754 struct acpi_device_wakeup *wakeup = &adev->wakeup; 755 acpi_status status; 756 int error = 0; 757 758 mutex_lock(&acpi_wakeup_lock); 759 760 if (wakeup->enable_count >= max_count) 761 goto out; 762 763 if (wakeup->enable_count > 0) 764 goto inc; 765 766 error = acpi_enable_wakeup_device_power(adev, target_state); 767 if (error) 768 goto out; 769 770 status = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number); 771 if (ACPI_FAILURE(status)) { 772 acpi_disable_wakeup_device_power(adev); 773 error = -EIO; 774 goto out; 775 } 776 777 acpi_handle_debug(adev->handle, "GPE%2X enabled for wakeup\n", 778 (unsigned int)wakeup->gpe_number); 779 780 inc: 781 wakeup->enable_count++; 782 783 out: 784 mutex_unlock(&acpi_wakeup_lock); 785 return error; 786 } 787 788 /** 789 * acpi_device_wakeup_enable - Enable wakeup functionality for device. 790 * @adev: ACPI device to enable wakeup functionality for. 791 * @target_state: State the system is transitioning into. 792 * 793 * Enable the GPE associated with @adev so that it can generate wakeup signals 794 * for the device in response to external (remote) events and enable wakeup 795 * power for it. 796 * 797 * Callers must ensure that @adev is a valid ACPI device node before executing 798 * this function. 799 */ 800 static int acpi_device_wakeup_enable(struct acpi_device *adev, u32 target_state) 801 { 802 return __acpi_device_wakeup_enable(adev, target_state, 1); 803 } 804 805 /** 806 * acpi_device_wakeup_disable - Disable wakeup functionality for device. 807 * @adev: ACPI device to disable wakeup functionality for. 808 * 809 * Disable the GPE associated with @adev and disable wakeup power for it. 810 * 811 * Callers must ensure that @adev is a valid ACPI device node before executing 812 * this function. 813 */ 814 static void acpi_device_wakeup_disable(struct acpi_device *adev) 815 { 816 struct acpi_device_wakeup *wakeup = &adev->wakeup; 817 818 mutex_lock(&acpi_wakeup_lock); 819 820 if (!wakeup->enable_count) 821 goto out; 822 823 acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number); 824 acpi_disable_wakeup_device_power(adev); 825 826 wakeup->enable_count--; 827 828 out: 829 mutex_unlock(&acpi_wakeup_lock); 830 } 831 832 static int __acpi_pm_set_device_wakeup(struct device *dev, bool enable, 833 int max_count) 834 { 835 struct acpi_device *adev; 836 int error; 837 838 adev = ACPI_COMPANION(dev); 839 if (!adev) { 840 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__); 841 return -ENODEV; 842 } 843 844 if (!acpi_device_can_wakeup(adev)) 845 return -EINVAL; 846 847 if (!enable) { 848 acpi_device_wakeup_disable(adev); 849 dev_dbg(dev, "Wakeup disabled by ACPI\n"); 850 return 0; 851 } 852 853 error = __acpi_device_wakeup_enable(adev, acpi_target_system_state(), 854 max_count); 855 if (!error) 856 dev_dbg(dev, "Wakeup enabled by ACPI\n"); 857 858 return error; 859 } 860 861 /** 862 * acpi_pm_set_device_wakeup - Enable/disable remote wakeup for given device. 863 * @dev: Device to enable/disable to generate wakeup events. 864 * @enable: Whether to enable or disable the wakeup functionality. 865 */ 866 int acpi_pm_set_device_wakeup(struct device *dev, bool enable) 867 { 868 return __acpi_pm_set_device_wakeup(dev, enable, 1); 869 } 870 EXPORT_SYMBOL_GPL(acpi_pm_set_device_wakeup); 871 872 /** 873 * acpi_pm_set_bridge_wakeup - Enable/disable remote wakeup for given bridge. 874 * @dev: Bridge device to enable/disable to generate wakeup events. 875 * @enable: Whether to enable or disable the wakeup functionality. 876 */ 877 int acpi_pm_set_bridge_wakeup(struct device *dev, bool enable) 878 { 879 return __acpi_pm_set_device_wakeup(dev, enable, INT_MAX); 880 } 881 EXPORT_SYMBOL_GPL(acpi_pm_set_bridge_wakeup); 882 883 /** 884 * acpi_dev_pm_low_power - Put ACPI device into a low-power state. 885 * @dev: Device to put into a low-power state. 886 * @adev: ACPI device node corresponding to @dev. 887 * @system_state: System state to choose the device state for. 888 */ 889 static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev, 890 u32 system_state) 891 { 892 int ret, state; 893 894 if (!acpi_device_power_manageable(adev)) 895 return 0; 896 897 ret = acpi_dev_pm_get_state(dev, adev, system_state, NULL, &state); 898 return ret ? ret : acpi_device_set_power(adev, state); 899 } 900 901 /** 902 * acpi_dev_pm_full_power - Put ACPI device into the full-power state. 903 * @adev: ACPI device node to put into the full-power state. 904 */ 905 static int acpi_dev_pm_full_power(struct acpi_device *adev) 906 { 907 return acpi_device_power_manageable(adev) ? 908 acpi_device_set_power(adev, ACPI_STATE_D0) : 0; 909 } 910 911 /** 912 * acpi_dev_suspend - Put device into a low-power state using ACPI. 913 * @dev: Device to put into a low-power state. 914 * @wakeup: Whether or not to enable wakeup for the device. 915 * 916 * Put the given device into a low-power state using the standard ACPI 917 * mechanism. Set up remote wakeup if desired, choose the state to put the 918 * device into (this checks if remote wakeup is expected to work too), and set 919 * the power state of the device. 920 */ 921 int acpi_dev_suspend(struct device *dev, bool wakeup) 922 { 923 struct acpi_device *adev = ACPI_COMPANION(dev); 924 u32 target_state = acpi_target_system_state(); 925 int error; 926 927 if (!adev) 928 return 0; 929 930 if (wakeup && acpi_device_can_wakeup(adev)) { 931 error = acpi_device_wakeup_enable(adev, target_state); 932 if (error) 933 return -EAGAIN; 934 } else { 935 wakeup = false; 936 } 937 938 error = acpi_dev_pm_low_power(dev, adev, target_state); 939 if (error && wakeup) 940 acpi_device_wakeup_disable(adev); 941 942 return error; 943 } 944 EXPORT_SYMBOL_GPL(acpi_dev_suspend); 945 946 /** 947 * acpi_dev_resume - Put device into the full-power state using ACPI. 948 * @dev: Device to put into the full-power state. 949 * 950 * Put the given device into the full-power state using the standard ACPI 951 * mechanism. Set the power state of the device to ACPI D0 and disable wakeup. 952 */ 953 int acpi_dev_resume(struct device *dev) 954 { 955 struct acpi_device *adev = ACPI_COMPANION(dev); 956 int error; 957 958 if (!adev) 959 return 0; 960 961 error = acpi_dev_pm_full_power(adev); 962 acpi_device_wakeup_disable(adev); 963 return error; 964 } 965 EXPORT_SYMBOL_GPL(acpi_dev_resume); 966 967 /** 968 * acpi_subsys_runtime_suspend - Suspend device using ACPI. 969 * @dev: Device to suspend. 970 * 971 * Carry out the generic runtime suspend procedure for @dev and use ACPI to put 972 * it into a runtime low-power state. 973 */ 974 int acpi_subsys_runtime_suspend(struct device *dev) 975 { 976 int ret = pm_generic_runtime_suspend(dev); 977 return ret ? ret : acpi_dev_suspend(dev, true); 978 } 979 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend); 980 981 /** 982 * acpi_subsys_runtime_resume - Resume device using ACPI. 983 * @dev: Device to Resume. 984 * 985 * Use ACPI to put the given device into the full-power state and carry out the 986 * generic runtime resume procedure for it. 987 */ 988 int acpi_subsys_runtime_resume(struct device *dev) 989 { 990 int ret = acpi_dev_resume(dev); 991 return ret ? ret : pm_generic_runtime_resume(dev); 992 } 993 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume); 994 995 #ifdef CONFIG_PM_SLEEP 996 static bool acpi_dev_needs_resume(struct device *dev, struct acpi_device *adev) 997 { 998 u32 sys_target = acpi_target_system_state(); 999 int ret, state; 1000 1001 if (!pm_runtime_suspended(dev) || !adev || (adev->wakeup.flags.valid && 1002 device_may_wakeup(dev) != !!adev->wakeup.prepare_count)) 1003 return true; 1004 1005 if (sys_target == ACPI_STATE_S0) 1006 return false; 1007 1008 if (adev->power.flags.dsw_present) 1009 return true; 1010 1011 ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state); 1012 if (ret) 1013 return true; 1014 1015 return state != adev->power.state; 1016 } 1017 1018 /** 1019 * acpi_subsys_prepare - Prepare device for system transition to a sleep state. 1020 * @dev: Device to prepare. 1021 */ 1022 int acpi_subsys_prepare(struct device *dev) 1023 { 1024 struct acpi_device *adev = ACPI_COMPANION(dev); 1025 1026 if (dev->driver && dev->driver->pm && dev->driver->pm->prepare) { 1027 int ret = dev->driver->pm->prepare(dev); 1028 1029 if (ret < 0) 1030 return ret; 1031 1032 if (!ret && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE)) 1033 return 0; 1034 } 1035 1036 return !acpi_dev_needs_resume(dev, adev); 1037 } 1038 EXPORT_SYMBOL_GPL(acpi_subsys_prepare); 1039 1040 /** 1041 * acpi_subsys_complete - Finalize device's resume during system resume. 1042 * @dev: Device to handle. 1043 */ 1044 void acpi_subsys_complete(struct device *dev) 1045 { 1046 pm_generic_complete(dev); 1047 /* 1048 * If the device had been runtime-suspended before the system went into 1049 * the sleep state it is going out of and it has never been resumed till 1050 * now, resume it in case the firmware powered it up. 1051 */ 1052 if (pm_runtime_suspended(dev) && pm_resume_via_firmware()) 1053 pm_request_resume(dev); 1054 } 1055 EXPORT_SYMBOL_GPL(acpi_subsys_complete); 1056 1057 /** 1058 * acpi_subsys_suspend - Run the device driver's suspend callback. 1059 * @dev: Device to handle. 1060 * 1061 * Follow PCI and resume devices from runtime suspend before running their 1062 * system suspend callbacks, unless the driver can cope with runtime-suspended 1063 * devices during system suspend and there are no ACPI-specific reasons for 1064 * resuming them. 1065 */ 1066 int acpi_subsys_suspend(struct device *dev) 1067 { 1068 if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) || 1069 acpi_dev_needs_resume(dev, ACPI_COMPANION(dev))) 1070 pm_runtime_resume(dev); 1071 1072 return pm_generic_suspend(dev); 1073 } 1074 EXPORT_SYMBOL_GPL(acpi_subsys_suspend); 1075 1076 /** 1077 * acpi_subsys_suspend_late - Suspend device using ACPI. 1078 * @dev: Device to suspend. 1079 * 1080 * Carry out the generic late suspend procedure for @dev and use ACPI to put 1081 * it into a low-power state during system transition into a sleep state. 1082 */ 1083 int acpi_subsys_suspend_late(struct device *dev) 1084 { 1085 int ret; 1086 1087 if (dev_pm_smart_suspend_and_suspended(dev)) 1088 return 0; 1089 1090 ret = pm_generic_suspend_late(dev); 1091 return ret ? ret : acpi_dev_suspend(dev, device_may_wakeup(dev)); 1092 } 1093 EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late); 1094 1095 /** 1096 * acpi_subsys_suspend_noirq - Run the device driver's "noirq" suspend callback. 1097 * @dev: Device to suspend. 1098 */ 1099 int acpi_subsys_suspend_noirq(struct device *dev) 1100 { 1101 int ret; 1102 1103 if (dev_pm_smart_suspend_and_suspended(dev)) { 1104 dev->power.may_skip_resume = true; 1105 return 0; 1106 } 1107 1108 ret = pm_generic_suspend_noirq(dev); 1109 if (ret) 1110 return ret; 1111 1112 /* 1113 * If the target system sleep state is suspend-to-idle, it is sufficient 1114 * to check whether or not the device's wakeup settings are good for 1115 * runtime PM. Otherwise, the pm_resume_via_firmware() check will cause 1116 * acpi_subsys_complete() to take care of fixing up the device's state 1117 * anyway, if need be. 1118 */ 1119 dev->power.may_skip_resume = device_may_wakeup(dev) || 1120 !device_can_wakeup(dev); 1121 1122 return 0; 1123 } 1124 EXPORT_SYMBOL_GPL(acpi_subsys_suspend_noirq); 1125 1126 /** 1127 * acpi_subsys_resume_noirq - Run the device driver's "noirq" resume callback. 1128 * @dev: Device to handle. 1129 */ 1130 static int acpi_subsys_resume_noirq(struct device *dev) 1131 { 1132 if (dev_pm_may_skip_resume(dev)) 1133 return 0; 1134 1135 /* 1136 * Devices with DPM_FLAG_SMART_SUSPEND may be left in runtime suspend 1137 * during system suspend, so update their runtime PM status to "active" 1138 * as they will be put into D0 going forward. 1139 */ 1140 if (dev_pm_smart_suspend_and_suspended(dev)) 1141 pm_runtime_set_active(dev); 1142 1143 return pm_generic_resume_noirq(dev); 1144 } 1145 1146 /** 1147 * acpi_subsys_resume_early - Resume device using ACPI. 1148 * @dev: Device to Resume. 1149 * 1150 * Use ACPI to put the given device into the full-power state and carry out the 1151 * generic early resume procedure for it during system transition into the 1152 * working state. 1153 */ 1154 static int acpi_subsys_resume_early(struct device *dev) 1155 { 1156 int ret = acpi_dev_resume(dev); 1157 return ret ? ret : pm_generic_resume_early(dev); 1158 } 1159 1160 /** 1161 * acpi_subsys_freeze - Run the device driver's freeze callback. 1162 * @dev: Device to handle. 1163 */ 1164 int acpi_subsys_freeze(struct device *dev) 1165 { 1166 /* 1167 * Resume all runtime-suspended devices before creating a snapshot 1168 * image of system memory, because the restore kernel generally cannot 1169 * be expected to always handle them consistently and they need to be 1170 * put into the runtime-active metastate during system resume anyway, 1171 * so it is better to ensure that the state saved in the image will be 1172 * always consistent with that. 1173 */ 1174 pm_runtime_resume(dev); 1175 1176 return pm_generic_freeze(dev); 1177 } 1178 EXPORT_SYMBOL_GPL(acpi_subsys_freeze); 1179 1180 /** 1181 * acpi_subsys_restore_early - Restore device using ACPI. 1182 * @dev: Device to restore. 1183 */ 1184 int acpi_subsys_restore_early(struct device *dev) 1185 { 1186 int ret = acpi_dev_resume(dev); 1187 return ret ? ret : pm_generic_restore_early(dev); 1188 } 1189 EXPORT_SYMBOL_GPL(acpi_subsys_restore_early); 1190 1191 /** 1192 * acpi_subsys_poweroff - Run the device driver's poweroff callback. 1193 * @dev: Device to handle. 1194 * 1195 * Follow PCI and resume devices from runtime suspend before running their 1196 * system poweroff callbacks, unless the driver can cope with runtime-suspended 1197 * devices during system suspend and there are no ACPI-specific reasons for 1198 * resuming them. 1199 */ 1200 int acpi_subsys_poweroff(struct device *dev) 1201 { 1202 if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) || 1203 acpi_dev_needs_resume(dev, ACPI_COMPANION(dev))) 1204 pm_runtime_resume(dev); 1205 1206 return pm_generic_poweroff(dev); 1207 } 1208 EXPORT_SYMBOL_GPL(acpi_subsys_poweroff); 1209 1210 /** 1211 * acpi_subsys_poweroff_late - Run the device driver's poweroff callback. 1212 * @dev: Device to handle. 1213 * 1214 * Carry out the generic late poweroff procedure for @dev and use ACPI to put 1215 * it into a low-power state during system transition into a sleep state. 1216 */ 1217 static int acpi_subsys_poweroff_late(struct device *dev) 1218 { 1219 int ret; 1220 1221 if (dev_pm_smart_suspend_and_suspended(dev)) 1222 return 0; 1223 1224 ret = pm_generic_poweroff_late(dev); 1225 if (ret) 1226 return ret; 1227 1228 return acpi_dev_suspend(dev, device_may_wakeup(dev)); 1229 } 1230 1231 /** 1232 * acpi_subsys_poweroff_noirq - Run the driver's "noirq" poweroff callback. 1233 * @dev: Device to suspend. 1234 */ 1235 static int acpi_subsys_poweroff_noirq(struct device *dev) 1236 { 1237 if (dev_pm_smart_suspend_and_suspended(dev)) 1238 return 0; 1239 1240 return pm_generic_poweroff_noirq(dev); 1241 } 1242 #endif /* CONFIG_PM_SLEEP */ 1243 1244 static struct dev_pm_domain acpi_general_pm_domain = { 1245 .ops = { 1246 .runtime_suspend = acpi_subsys_runtime_suspend, 1247 .runtime_resume = acpi_subsys_runtime_resume, 1248 #ifdef CONFIG_PM_SLEEP 1249 .prepare = acpi_subsys_prepare, 1250 .complete = acpi_subsys_complete, 1251 .suspend = acpi_subsys_suspend, 1252 .suspend_late = acpi_subsys_suspend_late, 1253 .suspend_noirq = acpi_subsys_suspend_noirq, 1254 .resume_noirq = acpi_subsys_resume_noirq, 1255 .resume_early = acpi_subsys_resume_early, 1256 .freeze = acpi_subsys_freeze, 1257 .poweroff = acpi_subsys_poweroff, 1258 .poweroff_late = acpi_subsys_poweroff_late, 1259 .poweroff_noirq = acpi_subsys_poweroff_noirq, 1260 .restore_early = acpi_subsys_restore_early, 1261 #endif 1262 }, 1263 }; 1264 1265 /** 1266 * acpi_dev_pm_detach - Remove ACPI power management from the device. 1267 * @dev: Device to take care of. 1268 * @power_off: Whether or not to try to remove power from the device. 1269 * 1270 * Remove the device from the general ACPI PM domain and remove its wakeup 1271 * notifier. If @power_off is set, additionally remove power from the device if 1272 * possible. 1273 * 1274 * Callers must ensure proper synchronization of this function with power 1275 * management callbacks. 1276 */ 1277 static void acpi_dev_pm_detach(struct device *dev, bool power_off) 1278 { 1279 struct acpi_device *adev = ACPI_COMPANION(dev); 1280 1281 if (adev && dev->pm_domain == &acpi_general_pm_domain) { 1282 dev_pm_domain_set(dev, NULL); 1283 acpi_remove_pm_notifier(adev); 1284 if (power_off) { 1285 /* 1286 * If the device's PM QoS resume latency limit or flags 1287 * have been exposed to user space, they have to be 1288 * hidden at this point, so that they don't affect the 1289 * choice of the low-power state to put the device into. 1290 */ 1291 dev_pm_qos_hide_latency_limit(dev); 1292 dev_pm_qos_hide_flags(dev); 1293 acpi_device_wakeup_disable(adev); 1294 acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0); 1295 } 1296 } 1297 } 1298 1299 /** 1300 * acpi_dev_pm_attach - Prepare device for ACPI power management. 1301 * @dev: Device to prepare. 1302 * @power_on: Whether or not to power on the device. 1303 * 1304 * If @dev has a valid ACPI handle that has a valid struct acpi_device object 1305 * attached to it, install a wakeup notification handler for the device and 1306 * add it to the general ACPI PM domain. If @power_on is set, the device will 1307 * be put into the ACPI D0 state before the function returns. 1308 * 1309 * This assumes that the @dev's bus type uses generic power management callbacks 1310 * (or doesn't use any power management callbacks at all). 1311 * 1312 * Callers must ensure proper synchronization of this function with power 1313 * management callbacks. 1314 */ 1315 int acpi_dev_pm_attach(struct device *dev, bool power_on) 1316 { 1317 /* 1318 * Skip devices whose ACPI companions match the device IDs below, 1319 * because they require special power management handling incompatible 1320 * with the generic ACPI PM domain. 1321 */ 1322 static const struct acpi_device_id special_pm_ids[] = { 1323 {"PNP0C0B", }, /* Generic ACPI fan */ 1324 {"INT1044", }, /* Fan for Tiger Lake generation */ 1325 {"INT3404", }, /* Fan */ 1326 {} 1327 }; 1328 struct acpi_device *adev = ACPI_COMPANION(dev); 1329 1330 if (!adev || !acpi_match_device_ids(adev, special_pm_ids)) 1331 return 0; 1332 1333 /* 1334 * Only attach the power domain to the first device if the 1335 * companion is shared by multiple. This is to prevent doing power 1336 * management twice. 1337 */ 1338 if (!acpi_device_is_first_physical_node(adev, dev)) 1339 return 0; 1340 1341 acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func); 1342 dev_pm_domain_set(dev, &acpi_general_pm_domain); 1343 if (power_on) { 1344 acpi_dev_pm_full_power(adev); 1345 acpi_device_wakeup_disable(adev); 1346 } 1347 1348 dev->pm_domain->detach = acpi_dev_pm_detach; 1349 return 1; 1350 } 1351 EXPORT_SYMBOL_GPL(acpi_dev_pm_attach); 1352 #endif /* CONFIG_PM */ 1353