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1// SPDX-License-Identifier: GPL-2.0-only2/*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#define pr_fmt(fmt) "PM: " fmt14 15#include <linux/acpi.h>16#include <linux/export.h>17#include <linux/mutex.h>18#include <linux/pm_qos.h>19#include <linux/pm_domain.h>20#include <linux/pm_runtime.h>21#include <linux/suspend.h>22 23#include "fan.h"24#include "internal.h"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 */30const 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 48static 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 may67 * update its parent's power.state field (when the parent's power state is68 * 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 that71 * the power state returned by it will be persistent and it may return a power72 * state shallower than previously set by acpi_device_set_power() for @device73 * (if that power state depends on any power resources).74 */75int acpi_device_get_power(struct acpi_device *device, int *state)76{77 int result = ACPI_STATE_UNKNOWN;78 struct acpi_device *parent;79 int error;80 81 if (!device || !state)82 return -EINVAL;83 84 parent = acpi_dev_parent(device);85 86 if (!device->flags.power_manageable) {87 /* TBD: Non-recursive algorithm for walking up hierarchy. */88 *state = parent ? parent->power.state : ACPI_STATE_D0;89 goto out;90 }91 92 /*93 * Get the device's power state from power resources settings and _PSC,94 * if available.95 */96 if (device->power.flags.power_resources) {97 error = acpi_power_get_inferred_state(device, &result);98 if (error)99 return error;100 }101 if (device->power.flags.explicit_get) {102 int psc;103 104 error = acpi_dev_pm_explicit_get(device, &psc);105 if (error)106 return error;107 108 /*109 * The power resources settings may indicate a power state110 * shallower than the actual power state of the device, because111 * the same power resources may be referenced by other devices.112 *113 * For systems predating ACPI 4.0 we assume that D3hot is the114 * deepest state that can be supported.115 */116 if (psc > result && psc < ACPI_STATE_D3_COLD)117 result = psc;118 else if (result == ACPI_STATE_UNKNOWN)119 result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_HOT : psc;120 }121 122 /*123 * If we were unsure about the device parent's power state up to this124 * point, the fact that the device is in D0 implies that the parent has125 * to be in D0 too, except if ignore_parent is set.126 */127 if (!device->power.flags.ignore_parent && parent &&128 parent->power.state == ACPI_STATE_UNKNOWN &&129 result == ACPI_STATE_D0)130 parent->power.state = ACPI_STATE_D0;131 132 *state = result;133 134 out:135 acpi_handle_debug(device->handle, "Power state: %s\n",136 acpi_power_state_string(*state));137 138 return 0;139}140 141static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state)142{143 if (adev->power.states[state].flags.explicit_set) {144 char method[5] = { '_', 'P', 'S', '0' + state, '\0' };145 acpi_status status;146 147 status = acpi_evaluate_object(adev->handle, method, NULL, NULL);148 if (ACPI_FAILURE(status))149 return -ENODEV;150 }151 return 0;152}153 154/**155 * acpi_device_set_power - Set power state of an ACPI device.156 * @device: Device to set the power state of.157 * @state: New power state to set.158 *159 * Callers must ensure that the device is power manageable before using this160 * function.161 */162int acpi_device_set_power(struct acpi_device *device, int state)163{164 int target_state = state;165 int result = 0;166 167 if (!device || !device->flags.power_manageable168 || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))169 return -EINVAL;170 171 acpi_handle_debug(device->handle, "Power state change: %s -> %s\n",172 acpi_power_state_string(device->power.state),173 acpi_power_state_string(state));174 175 /* Make sure this is a valid target state */176 177 /* There is a special case for D0 addressed below. */178 if (state > ACPI_STATE_D0 && state == device->power.state)179 goto no_change;180 181 if (state == ACPI_STATE_D3_COLD) {182 /*183 * For transitions to D3cold we need to execute _PS3 and then184 * possibly drop references to the power resources in use.185 */186 state = ACPI_STATE_D3_HOT;187 /* If D3cold is not supported, use D3hot as the target state. */188 if (!device->power.states[ACPI_STATE_D3_COLD].flags.valid)189 target_state = state;190 } else if (!device->power.states[state].flags.valid) {191 acpi_handle_debug(device->handle, "Power state %s not supported\n",192 acpi_power_state_string(state));193 return -ENODEV;194 }195 196 if (!device->power.flags.ignore_parent) {197 struct acpi_device *parent;198 199 parent = acpi_dev_parent(device);200 if (parent && state < parent->power.state) {201 acpi_handle_debug(device->handle,202 "Cannot transition to %s for parent in %s\n",203 acpi_power_state_string(state),204 acpi_power_state_string(parent->power.state));205 return -ENODEV;206 }207 }208 209 /*210 * Transition Power211 * ----------------212 * In accordance with ACPI 6, _PSx is executed before manipulating power213 * resources, unless the target state is D0, in which case _PS0 is214 * supposed to be executed after turning the power resources on.215 */216 if (state > ACPI_STATE_D0) {217 /*218 * According to ACPI 6, devices cannot go from lower-power219 * (deeper) states to higher-power (shallower) states.220 */221 if (state < device->power.state) {222 acpi_handle_debug(device->handle,223 "Cannot transition from %s to %s\n",224 acpi_power_state_string(device->power.state),225 acpi_power_state_string(state));226 return -ENODEV;227 }228 229 /*230 * If the device goes from D3hot to D3cold, _PS3 has been231 * evaluated for it already, so skip it in that case.232 */233 if (device->power.state < ACPI_STATE_D3_HOT) {234 result = acpi_dev_pm_explicit_set(device, state);235 if (result)236 goto end;237 }238 239 if (device->power.flags.power_resources)240 result = acpi_power_transition(device, target_state);241 } else {242 int cur_state = device->power.state;243 244 if (device->power.flags.power_resources) {245 result = acpi_power_transition(device, ACPI_STATE_D0);246 if (result)247 goto end;248 }249 250 if (cur_state == ACPI_STATE_D0) {251 int psc;252 253 /* Nothing to do here if _PSC is not present. */254 if (!device->power.flags.explicit_get)255 goto no_change;256 257 /*258 * The power state of the device was set to D0 last259 * time, but that might have happened before a260 * system-wide transition involving the platform261 * firmware, so it may be necessary to evaluate _PS0262 * for the device here. However, use extra care here263 * and evaluate _PSC to check the device's current power264 * state, and only invoke _PS0 if the evaluation of _PSC265 * is successful and it returns a power state different266 * from D0.267 */268 result = acpi_dev_pm_explicit_get(device, &psc);269 if (result || psc == ACPI_STATE_D0)270 goto no_change;271 }272 273 result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);274 }275 276end:277 if (result) {278 acpi_handle_debug(device->handle,279 "Failed to change power state to %s\n",280 acpi_power_state_string(target_state));281 } else {282 device->power.state = target_state;283 acpi_handle_debug(device->handle, "Power state changed to %s\n",284 acpi_power_state_string(target_state));285 }286 287 return result;288 289no_change:290 acpi_handle_debug(device->handle, "Already in %s\n",291 acpi_power_state_string(state));292 return 0;293}294EXPORT_SYMBOL(acpi_device_set_power);295 296int acpi_bus_set_power(acpi_handle handle, int state)297{298 struct acpi_device *device = acpi_fetch_acpi_dev(handle);299 300 if (device)301 return acpi_device_set_power(device, state);302 303 return -ENODEV;304}305EXPORT_SYMBOL(acpi_bus_set_power);306 307int acpi_bus_init_power(struct acpi_device *device)308{309 int state;310 int result;311 312 if (!device)313 return -EINVAL;314 315 device->power.state = ACPI_STATE_UNKNOWN;316 if (!acpi_device_is_present(device)) {317 device->flags.initialized = false;318 return -ENXIO;319 }320 321 result = acpi_device_get_power(device, &state);322 if (result)323 return result;324 325 if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {326 /* Reference count the power resources. */327 result = acpi_power_on_resources(device, state);328 if (result)329 return result;330 331 if (state == ACPI_STATE_D0) {332 /*333 * If _PSC is not present and the state inferred from334 * power resources appears to be D0, it still may be335 * necessary to execute _PS0 at this point, because336 * another device using the same power resources may337 * have been put into D0 previously and that's why we338 * see D0 here.339 */340 result = acpi_dev_pm_explicit_set(device, state);341 if (result)342 return result;343 }344 } else if (state == ACPI_STATE_UNKNOWN) {345 /*346 * No power resources and missing _PSC? Cross fingers and make347 * it D0 in hope that this is what the BIOS put the device into.348 * [We tried to force D0 here by executing _PS0, but that broke349 * Toshiba P870-303 in a nasty way.]350 */351 state = ACPI_STATE_D0;352 }353 device->power.state = state;354 return 0;355}356 357/**358 * acpi_device_fix_up_power - Force device with missing _PSC into D0.359 * @device: Device object whose power state is to be fixed up.360 *361 * Devices without power resources and _PSC, but having _PS0 and _PS3 defined,362 * are assumed to be put into D0 by the BIOS. However, in some cases that may363 * not be the case and this function should be used then.364 */365int acpi_device_fix_up_power(struct acpi_device *device)366{367 int ret = 0;368 369 if (!device->power.flags.power_resources370 && !device->power.flags.explicit_get371 && device->power.state == ACPI_STATE_D0)372 ret = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);373 374 return ret;375}376EXPORT_SYMBOL_GPL(acpi_device_fix_up_power);377 378static int fix_up_power_if_applicable(struct acpi_device *adev, void *not_used)379{380 if (adev->status.present && adev->status.enabled)381 acpi_device_fix_up_power(adev);382 383 return 0;384}385 386/**387 * acpi_device_fix_up_power_extended - Force device and its children into D0.388 * @adev: Parent device object whose power state is to be fixed up.389 *390 * Call acpi_device_fix_up_power() for @adev and its children so long as they391 * are reported as present and enabled.392 */393void acpi_device_fix_up_power_extended(struct acpi_device *adev)394{395 acpi_device_fix_up_power(adev);396 acpi_dev_for_each_child(adev, fix_up_power_if_applicable, NULL);397}398EXPORT_SYMBOL_GPL(acpi_device_fix_up_power_extended);399 400/**401 * acpi_device_fix_up_power_children - Force a device's children into D0.402 * @adev: Parent device object whose children's power state is to be fixed up.403 *404 * Call acpi_device_fix_up_power() for @adev's children so long as they405 * are reported as present and enabled.406 */407void acpi_device_fix_up_power_children(struct acpi_device *adev)408{409 acpi_dev_for_each_child(adev, fix_up_power_if_applicable, NULL);410}411EXPORT_SYMBOL_GPL(acpi_device_fix_up_power_children);412 413int acpi_device_update_power(struct acpi_device *device, int *state_p)414{415 int state;416 int result;417 418 if (device->power.state == ACPI_STATE_UNKNOWN) {419 result = acpi_bus_init_power(device);420 if (!result && state_p)421 *state_p = device->power.state;422 423 return result;424 }425 426 result = acpi_device_get_power(device, &state);427 if (result)428 return result;429 430 if (state == ACPI_STATE_UNKNOWN) {431 state = ACPI_STATE_D0;432 result = acpi_device_set_power(device, state);433 if (result)434 return result;435 } else {436 if (device->power.flags.power_resources) {437 /*438 * We don't need to really switch the state, bu we need439 * to update the power resources' reference counters.440 */441 result = acpi_power_transition(device, state);442 if (result)443 return result;444 }445 device->power.state = state;446 }447 if (state_p)448 *state_p = state;449 450 return 0;451}452EXPORT_SYMBOL_GPL(acpi_device_update_power);453 454int acpi_bus_update_power(acpi_handle handle, int *state_p)455{456 struct acpi_device *device = acpi_fetch_acpi_dev(handle);457 458 if (device)459 return acpi_device_update_power(device, state_p);460 461 return -ENODEV;462}463EXPORT_SYMBOL_GPL(acpi_bus_update_power);464 465bool acpi_bus_power_manageable(acpi_handle handle)466{467 struct acpi_device *device = acpi_fetch_acpi_dev(handle);468 469 return device && device->flags.power_manageable;470}471EXPORT_SYMBOL(acpi_bus_power_manageable);472 473static int acpi_power_up_if_adr_present(struct acpi_device *adev, void *not_used)474{475 if (!(adev->flags.power_manageable && adev->pnp.type.bus_address))476 return 0;477 478 acpi_handle_debug(adev->handle, "Power state: %s\n",479 acpi_power_state_string(adev->power.state));480 481 if (adev->power.state == ACPI_STATE_D3_COLD)482 return acpi_device_set_power(adev, ACPI_STATE_D0);483 484 return 0;485}486 487/**488 * acpi_dev_power_up_children_with_adr - Power up childres with valid _ADR489 * @adev: Parent ACPI device object.490 *491 * Change the power states of the direct children of @adev that are in D3cold492 * and hold valid _ADR objects to D0 in order to allow bus (e.g. PCI)493 * enumeration code to access them.494 */495void acpi_dev_power_up_children_with_adr(struct acpi_device *adev)496{497 acpi_dev_for_each_child(adev, acpi_power_up_if_adr_present, NULL);498}499 500/**501 * acpi_dev_power_state_for_wake - Deepest power state for wakeup signaling502 * @adev: ACPI companion of the target device.503 *504 * Evaluate _S0W for @adev and return the value produced by it or return505 * ACPI_STATE_UNKNOWN on errors (including _S0W not present).506 */507u8 acpi_dev_power_state_for_wake(struct acpi_device *adev)508{509 unsigned long long state;510 acpi_status status;511 512 status = acpi_evaluate_integer(adev->handle, "_S0W", NULL, &state);513 if (ACPI_FAILURE(status))514 return ACPI_STATE_UNKNOWN;515 516 return state;517}518 519#ifdef CONFIG_PM520static DEFINE_MUTEX(acpi_pm_notifier_lock);521static DEFINE_MUTEX(acpi_pm_notifier_install_lock);522 523void acpi_pm_wakeup_event(struct device *dev)524{525 pm_wakeup_dev_event(dev, 0, acpi_s2idle_wakeup());526}527EXPORT_SYMBOL_GPL(acpi_pm_wakeup_event);528 529static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used)530{531 struct acpi_device *adev;532 533 if (val != ACPI_NOTIFY_DEVICE_WAKE)534 return;535 536 acpi_handle_debug(handle, "Wake notify\n");537 538 adev = acpi_get_acpi_dev(handle);539 if (!adev)540 return;541 542 mutex_lock(&acpi_pm_notifier_lock);543 544 if (adev->wakeup.flags.notifier_present) {545 pm_wakeup_ws_event(adev->wakeup.ws, 0, acpi_s2idle_wakeup());546 if (adev->wakeup.context.func) {547 acpi_handle_debug(handle, "Running %pS for %s\n",548 adev->wakeup.context.func,549 dev_name(adev->wakeup.context.dev));550 adev->wakeup.context.func(&adev->wakeup.context);551 }552 }553 554 mutex_unlock(&acpi_pm_notifier_lock);555 556 acpi_put_acpi_dev(adev);557}558 559/**560 * acpi_add_pm_notifier - Register PM notify handler for given ACPI device.561 * @adev: ACPI device to add the notify handler for.562 * @dev: Device to generate a wakeup event for while handling the notification.563 * @func: Work function to execute when handling the notification.564 *565 * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of566 * PM wakeup events. For example, wakeup events may be generated for bridges567 * if one of the devices below the bridge is signaling wakeup, even if the568 * bridge itself doesn't have a wakeup GPE associated with it.569 */570acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev,571 void (*func)(struct acpi_device_wakeup_context *context))572{573 acpi_status status = AE_ALREADY_EXISTS;574 575 if (!dev && !func)576 return AE_BAD_PARAMETER;577 578 mutex_lock(&acpi_pm_notifier_install_lock);579 580 if (adev->wakeup.flags.notifier_present)581 goto out;582 583 status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY,584 acpi_pm_notify_handler, NULL);585 if (ACPI_FAILURE(status))586 goto out;587 588 mutex_lock(&acpi_pm_notifier_lock);589 adev->wakeup.ws = wakeup_source_register(&adev->dev,590 dev_name(&adev->dev));591 adev->wakeup.context.dev = dev;592 adev->wakeup.context.func = func;593 adev->wakeup.flags.notifier_present = true;594 mutex_unlock(&acpi_pm_notifier_lock);595 596 out:597 mutex_unlock(&acpi_pm_notifier_install_lock);598 return status;599}600 601/**602 * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.603 * @adev: ACPI device to remove the notifier from.604 */605acpi_status acpi_remove_pm_notifier(struct acpi_device *adev)606{607 acpi_status status = AE_BAD_PARAMETER;608 609 mutex_lock(&acpi_pm_notifier_install_lock);610 611 if (!adev->wakeup.flags.notifier_present)612 goto out;613 614 status = acpi_remove_notify_handler(adev->handle,615 ACPI_SYSTEM_NOTIFY,616 acpi_pm_notify_handler);617 if (ACPI_FAILURE(status))618 goto out;619 620 mutex_lock(&acpi_pm_notifier_lock);621 adev->wakeup.context.func = NULL;622 adev->wakeup.context.dev = NULL;623 wakeup_source_unregister(adev->wakeup.ws);624 adev->wakeup.flags.notifier_present = false;625 mutex_unlock(&acpi_pm_notifier_lock);626 627 out:628 mutex_unlock(&acpi_pm_notifier_install_lock);629 return status;630}631 632bool acpi_bus_can_wakeup(acpi_handle handle)633{634 struct acpi_device *device = acpi_fetch_acpi_dev(handle);635 636 return device && device->wakeup.flags.valid;637}638EXPORT_SYMBOL(acpi_bus_can_wakeup);639 640bool acpi_pm_device_can_wakeup(struct device *dev)641{642 struct acpi_device *adev = ACPI_COMPANION(dev);643 644 return adev ? acpi_device_can_wakeup(adev) : false;645}646 647/**648 * acpi_dev_pm_get_state - Get preferred power state of ACPI device.649 * @dev: Device whose preferred target power state to return.650 * @adev: ACPI device node corresponding to @dev.651 * @target_state: System state to match the resultant device state.652 * @d_min_p: Location to store the highest power state available to the device.653 * @d_max_p: Location to store the lowest power state available to the device.654 *655 * Find the lowest power (highest number) and highest power (lowest number) ACPI656 * device power states that the device can be in while the system is in the657 * state represented by @target_state. Store the integer numbers representing658 * those stats in the memory locations pointed to by @d_max_p and @d_min_p,659 * respectively.660 *661 * Callers must ensure that @dev and @adev are valid pointers and that @adev662 * actually corresponds to @dev before using this function.663 *664 * Returns 0 on success or -ENODATA when one of the ACPI methods fails or665 * returns a value that doesn't make sense. The memory locations pointed to by666 * @d_max_p and @d_min_p are only modified on success.667 */668static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev,669 u32 target_state, int *d_min_p, int *d_max_p)670{671 char method[] = { '_', 'S', '0' + target_state, 'D', '\0' };672 acpi_handle handle = adev->handle;673 unsigned long long ret;674 int d_min, d_max;675 bool wakeup = false;676 bool has_sxd = false;677 acpi_status status;678 679 /*680 * If the system state is S0, the lowest power state the device can be681 * in is D3cold, unless the device has _S0W and is supposed to signal682 * wakeup, in which case the return value of _S0W has to be used as the683 * lowest power state available to the device.684 */685 d_min = ACPI_STATE_D0;686 d_max = ACPI_STATE_D3_COLD;687 688 /*689 * If present, _SxD methods return the minimum D-state (highest power690 * state) we can use for the corresponding S-states. Otherwise, the691 * minimum D-state is D0 (ACPI 3.x).692 */693 if (target_state > ACPI_STATE_S0) {694 /*695 * We rely on acpi_evaluate_integer() not clobbering the integer696 * provided if AE_NOT_FOUND is returned.697 */698 ret = d_min;699 status = acpi_evaluate_integer(handle, method, NULL, &ret);700 if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND)701 || ret > ACPI_STATE_D3_COLD)702 return -ENODATA;703 704 /*705 * We need to handle legacy systems where D3hot and D3cold are706 * the same and 3 is returned in both cases, so fall back to707 * D3cold if D3hot is not a valid state.708 */709 if (!adev->power.states[ret].flags.valid) {710 if (ret == ACPI_STATE_D3_HOT)711 ret = ACPI_STATE_D3_COLD;712 else713 return -ENODATA;714 }715 716 if (status == AE_OK)717 has_sxd = true;718 719 d_min = ret;720 wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid721 && adev->wakeup.sleep_state >= target_state;722 } else if (device_may_wakeup(dev) && dev->power.wakeirq) {723 /*724 * The ACPI subsystem doesn't manage the wake bit for IRQs725 * defined with ExclusiveAndWake and SharedAndWake. Instead we726 * expect them to be managed via the PM subsystem. Drivers727 * should call dev_pm_set_wake_irq to register an IRQ as a wake728 * source.729 *730 * If a device has a wake IRQ attached we need to check the731 * _S0W method to get the correct wake D-state. Otherwise we732 * end up putting the device into D3Cold which will more than733 * likely disable wake functionality.734 */735 wakeup = true;736 } else {737 /* ACPI GPE is specified in _PRW. */738 wakeup = adev->wakeup.flags.valid;739 }740 741 /*742 * If _PRW says we can wake up the system from the target sleep state,743 * the D-state returned by _SxD is sufficient for that (we assume a744 * wakeup-aware driver if wake is set). Still, if _SxW exists745 * (ACPI 3.x), it should return the maximum (lowest power) D-state that746 * can wake the system. _S0W may be valid, too.747 */748 if (wakeup) {749 method[3] = 'W';750 status = acpi_evaluate_integer(handle, method, NULL, &ret);751 if (status == AE_NOT_FOUND) {752 /* No _SxW. In this case, the ACPI spec says that we753 * must not go into any power state deeper than the754 * value returned from _SxD.755 */756 if (has_sxd && target_state > ACPI_STATE_S0)757 d_max = d_min;758 } else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) {759 /* Fall back to D3cold if ret is not a valid state. */760 if (!adev->power.states[ret].flags.valid)761 ret = ACPI_STATE_D3_COLD;762 763 d_max = ret > d_min ? ret : d_min;764 } else {765 return -ENODATA;766 }767 }768 769 if (d_min_p)770 *d_min_p = d_min;771 772 if (d_max_p)773 *d_max_p = d_max;774 775 return 0;776}777 778/**779 * acpi_pm_device_sleep_state - Get preferred power state of ACPI device.780 * @dev: Device whose preferred target power state to return.781 * @d_min_p: Location to store the upper limit of the allowed states range.782 * @d_max_in: Deepest low-power state to take into consideration.783 * Return value: Preferred power state of the device on success, -ENODEV784 * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is785 * incorrect, or -ENODATA on ACPI method failure.786 *787 * The caller must ensure that @dev is valid before using this function.788 */789int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)790{791 struct acpi_device *adev;792 int ret, d_min, d_max;793 794 if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD)795 return -EINVAL;796 797 if (d_max_in > ACPI_STATE_D2) {798 enum pm_qos_flags_status stat;799 800 stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);801 if (stat == PM_QOS_FLAGS_ALL)802 d_max_in = ACPI_STATE_D2;803 }804 805 adev = ACPI_COMPANION(dev);806 if (!adev) {807 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);808 return -ENODEV;809 }810 811 ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(),812 &d_min, &d_max);813 if (ret)814 return ret;815 816 if (d_max_in < d_min)817 return -EINVAL;818 819 if (d_max > d_max_in) {820 for (d_max = d_max_in; d_max > d_min; d_max--) {821 if (adev->power.states[d_max].flags.valid)822 break;823 }824 }825 826 if (d_min_p)827 *d_min_p = d_min;828 829 return d_max;830}831EXPORT_SYMBOL(acpi_pm_device_sleep_state);832 833/**834 * acpi_pm_notify_work_func - ACPI devices wakeup notification work function.835 * @context: Device wakeup context.836 */837static void acpi_pm_notify_work_func(struct acpi_device_wakeup_context *context)838{839 struct device *dev = context->dev;840 841 if (dev) {842 pm_wakeup_event(dev, 0);843 pm_request_resume(dev);844 }845}846 847static DEFINE_MUTEX(acpi_wakeup_lock);848 849static int __acpi_device_wakeup_enable(struct acpi_device *adev,850 u32 target_state)851{852 struct acpi_device_wakeup *wakeup = &adev->wakeup;853 acpi_status status;854 int error = 0;855 856 mutex_lock(&acpi_wakeup_lock);857 858 /*859 * If the device wakeup power is already enabled, disable it and enable860 * it again in case it depends on the configuration of subordinate861 * devices and the conditions have changed since it was enabled last862 * time.863 */864 if (wakeup->enable_count > 0)865 acpi_disable_wakeup_device_power(adev);866 867 error = acpi_enable_wakeup_device_power(adev, target_state);868 if (error) {869 if (wakeup->enable_count > 0) {870 acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);871 wakeup->enable_count = 0;872 }873 goto out;874 }875 876 if (wakeup->enable_count > 0)877 goto inc;878 879 status = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);880 if (ACPI_FAILURE(status)) {881 acpi_disable_wakeup_device_power(adev);882 error = -EIO;883 goto out;884 }885 886 acpi_handle_debug(adev->handle, "GPE%2X enabled for wakeup\n",887 (unsigned int)wakeup->gpe_number);888 889inc:890 if (wakeup->enable_count < INT_MAX)891 wakeup->enable_count++;892 else893 acpi_handle_info(adev->handle, "Wakeup enable count out of bounds!\n");894 895out:896 mutex_unlock(&acpi_wakeup_lock);897 return error;898}899 900/**901 * acpi_device_wakeup_enable - Enable wakeup functionality for device.902 * @adev: ACPI device to enable wakeup functionality for.903 * @target_state: State the system is transitioning into.904 *905 * Enable the GPE associated with @adev so that it can generate wakeup signals906 * for the device in response to external (remote) events and enable wakeup907 * power for it.908 *909 * Callers must ensure that @adev is a valid ACPI device node before executing910 * this function.911 */912static int acpi_device_wakeup_enable(struct acpi_device *adev, u32 target_state)913{914 return __acpi_device_wakeup_enable(adev, target_state);915}916 917/**918 * acpi_device_wakeup_disable - Disable wakeup functionality for device.919 * @adev: ACPI device to disable wakeup functionality for.920 *921 * Disable the GPE associated with @adev and disable wakeup power for it.922 *923 * Callers must ensure that @adev is a valid ACPI device node before executing924 * this function.925 */926static void acpi_device_wakeup_disable(struct acpi_device *adev)927{928 struct acpi_device_wakeup *wakeup = &adev->wakeup;929 930 mutex_lock(&acpi_wakeup_lock);931 932 if (!wakeup->enable_count)933 goto out;934 935 acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);936 acpi_disable_wakeup_device_power(adev);937 938 wakeup->enable_count--;939 940out:941 mutex_unlock(&acpi_wakeup_lock);942}943 944/**945 * acpi_pm_set_device_wakeup - Enable/disable remote wakeup for given device.946 * @dev: Device to enable/disable to generate wakeup events.947 * @enable: Whether to enable or disable the wakeup functionality.948 */949int acpi_pm_set_device_wakeup(struct device *dev, bool enable)950{951 struct acpi_device *adev;952 int error;953 954 adev = ACPI_COMPANION(dev);955 if (!adev) {956 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);957 return -ENODEV;958 }959 960 if (!acpi_device_can_wakeup(adev))961 return -EINVAL;962 963 if (!enable) {964 acpi_device_wakeup_disable(adev);965 dev_dbg(dev, "Wakeup disabled by ACPI\n");966 return 0;967 }968 969 error = __acpi_device_wakeup_enable(adev, acpi_target_system_state());970 if (!error)971 dev_dbg(dev, "Wakeup enabled by ACPI\n");972 973 return error;974}975EXPORT_SYMBOL_GPL(acpi_pm_set_device_wakeup);976 977/**978 * acpi_dev_pm_low_power - Put ACPI device into a low-power state.979 * @dev: Device to put into a low-power state.980 * @adev: ACPI device node corresponding to @dev.981 * @system_state: System state to choose the device state for.982 */983static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev,984 u32 system_state)985{986 int ret, state;987 988 if (!acpi_device_power_manageable(adev))989 return 0;990 991 ret = acpi_dev_pm_get_state(dev, adev, system_state, NULL, &state);992 return ret ? ret : acpi_device_set_power(adev, state);993}994 995/**996 * acpi_dev_pm_full_power - Put ACPI device into the full-power state.997 * @adev: ACPI device node to put into the full-power state.998 */999static int acpi_dev_pm_full_power(struct acpi_device *adev)1000{1001 return acpi_device_power_manageable(adev) ?1002 acpi_device_set_power(adev, ACPI_STATE_D0) : 0;1003}1004 1005/**1006 * acpi_dev_suspend - Put device into a low-power state using ACPI.1007 * @dev: Device to put into a low-power state.1008 * @wakeup: Whether or not to enable wakeup for the device.1009 *1010 * Put the given device into a low-power state using the standard ACPI1011 * mechanism. Set up remote wakeup if desired, choose the state to put the1012 * device into (this checks if remote wakeup is expected to work too), and set1013 * the power state of the device.1014 */1015int acpi_dev_suspend(struct device *dev, bool wakeup)1016{1017 struct acpi_device *adev = ACPI_COMPANION(dev);1018 u32 target_state = acpi_target_system_state();1019 int error;1020 1021 if (!adev)1022 return 0;1023 1024 if (wakeup && acpi_device_can_wakeup(adev)) {1025 error = acpi_device_wakeup_enable(adev, target_state);1026 if (error)1027 return -EAGAIN;1028 } else {1029 wakeup = false;1030 }1031 1032 error = acpi_dev_pm_low_power(dev, adev, target_state);1033 if (error && wakeup)1034 acpi_device_wakeup_disable(adev);1035 1036 return error;1037}1038EXPORT_SYMBOL_GPL(acpi_dev_suspend);1039 1040/**1041 * acpi_dev_resume - Put device into the full-power state using ACPI.1042 * @dev: Device to put into the full-power state.1043 *1044 * Put the given device into the full-power state using the standard ACPI1045 * mechanism. Set the power state of the device to ACPI D0 and disable wakeup.1046 */1047int acpi_dev_resume(struct device *dev)1048{1049 struct acpi_device *adev = ACPI_COMPANION(dev);1050 int error;1051 1052 if (!adev)1053 return 0;1054 1055 error = acpi_dev_pm_full_power(adev);1056 acpi_device_wakeup_disable(adev);1057 return error;1058}1059EXPORT_SYMBOL_GPL(acpi_dev_resume);1060 1061/**1062 * acpi_subsys_runtime_suspend - Suspend device using ACPI.1063 * @dev: Device to suspend.1064 *1065 * Carry out the generic runtime suspend procedure for @dev and use ACPI to put1066 * it into a runtime low-power state.1067 */1068int acpi_subsys_runtime_suspend(struct device *dev)1069{1070 int ret = pm_generic_runtime_suspend(dev);1071 1072 return ret ? ret : acpi_dev_suspend(dev, true);1073}1074EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);1075 1076/**1077 * acpi_subsys_runtime_resume - Resume device using ACPI.1078 * @dev: Device to Resume.1079 *1080 * Use ACPI to put the given device into the full-power state and carry out the1081 * generic runtime resume procedure for it.1082 */1083int acpi_subsys_runtime_resume(struct device *dev)1084{1085 int ret = acpi_dev_resume(dev);1086 1087 return ret ? ret : pm_generic_runtime_resume(dev);1088}1089EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);1090 1091#ifdef CONFIG_PM_SLEEP1092static bool acpi_dev_needs_resume(struct device *dev, struct acpi_device *adev)1093{1094 u32 sys_target = acpi_target_system_state();1095 int ret, state;1096 1097 if (!pm_runtime_suspended(dev) || !adev || (adev->wakeup.flags.valid &&1098 device_may_wakeup(dev) != !!adev->wakeup.prepare_count))1099 return true;1100 1101 if (sys_target == ACPI_STATE_S0)1102 return false;1103 1104 if (adev->power.flags.dsw_present)1105 return true;1106 1107 ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state);1108 if (ret)1109 return true;1110 1111 return state != adev->power.state;1112}1113 1114/**1115 * acpi_subsys_prepare - Prepare device for system transition to a sleep state.1116 * @dev: Device to prepare.1117 */1118int acpi_subsys_prepare(struct device *dev)1119{1120 struct acpi_device *adev = ACPI_COMPANION(dev);1121 1122 if (dev->driver && dev->driver->pm && dev->driver->pm->prepare) {1123 int ret = dev->driver->pm->prepare(dev);1124 1125 if (ret < 0)1126 return ret;1127 1128 if (!ret && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))1129 return 0;1130 }1131 1132 return !acpi_dev_needs_resume(dev, adev);1133}1134EXPORT_SYMBOL_GPL(acpi_subsys_prepare);1135 1136/**1137 * acpi_subsys_complete - Finalize device's resume during system resume.1138 * @dev: Device to handle.1139 */1140void acpi_subsys_complete(struct device *dev)1141{1142 pm_generic_complete(dev);1143 /*1144 * If the device had been runtime-suspended before the system went into1145 * the sleep state it is going out of and it has never been resumed till1146 * now, resume it in case the firmware powered it up.1147 */1148 if (pm_runtime_suspended(dev) && pm_resume_via_firmware())1149 pm_request_resume(dev);1150}1151EXPORT_SYMBOL_GPL(acpi_subsys_complete);1152 1153/**1154 * acpi_subsys_suspend - Run the device driver's suspend callback.1155 * @dev: Device to handle.1156 *1157 * Follow PCI and resume devices from runtime suspend before running their1158 * system suspend callbacks, unless the driver can cope with runtime-suspended1159 * devices during system suspend and there are no ACPI-specific reasons for1160 * resuming them.1161 */1162int acpi_subsys_suspend(struct device *dev)1163{1164 if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||1165 acpi_dev_needs_resume(dev, ACPI_COMPANION(dev)))1166 pm_runtime_resume(dev);1167 1168 return pm_generic_suspend(dev);1169}1170EXPORT_SYMBOL_GPL(acpi_subsys_suspend);1171 1172/**1173 * acpi_subsys_suspend_late - Suspend device using ACPI.1174 * @dev: Device to suspend.1175 *1176 * Carry out the generic late suspend procedure for @dev and use ACPI to put1177 * it into a low-power state during system transition into a sleep state.1178 */1179int acpi_subsys_suspend_late(struct device *dev)1180{1181 int ret;1182 1183 if (dev_pm_skip_suspend(dev))1184 return 0;1185 1186 ret = pm_generic_suspend_late(dev);1187 return ret ? ret : acpi_dev_suspend(dev, device_may_wakeup(dev));1188}1189EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);1190 1191/**1192 * acpi_subsys_suspend_noirq - Run the device driver's "noirq" suspend callback.1193 * @dev: Device to suspend.1194 */1195int acpi_subsys_suspend_noirq(struct device *dev)1196{1197 int ret;1198 1199 if (dev_pm_skip_suspend(dev))1200 return 0;1201 1202 ret = pm_generic_suspend_noirq(dev);1203 if (ret)1204 return ret;1205 1206 /*1207 * If the target system sleep state is suspend-to-idle, it is sufficient1208 * to check whether or not the device's wakeup settings are good for1209 * runtime PM. Otherwise, the pm_resume_via_firmware() check will cause1210 * acpi_subsys_complete() to take care of fixing up the device's state1211 * anyway, if need be.1212 */1213 if (device_can_wakeup(dev) && !device_may_wakeup(dev))1214 dev->power.may_skip_resume = false;1215 1216 return 0;1217}1218EXPORT_SYMBOL_GPL(acpi_subsys_suspend_noirq);1219 1220/**1221 * acpi_subsys_resume_noirq - Run the device driver's "noirq" resume callback.1222 * @dev: Device to handle.1223 */1224static int acpi_subsys_resume_noirq(struct device *dev)1225{1226 if (dev_pm_skip_resume(dev))1227 return 0;1228 1229 return pm_generic_resume_noirq(dev);1230}1231 1232/**1233 * acpi_subsys_resume_early - Resume device using ACPI.1234 * @dev: Device to Resume.1235 *1236 * Use ACPI to put the given device into the full-power state and carry out the1237 * generic early resume procedure for it during system transition into the1238 * working state, but only do that if device either defines early resume1239 * handler, or does not define power operations at all. Otherwise powering up1240 * of the device is postponed to the normal resume phase.1241 */1242static int acpi_subsys_resume_early(struct device *dev)1243{1244 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;1245 int ret;1246 1247 if (dev_pm_skip_resume(dev))1248 return 0;1249 1250 if (pm && !pm->resume_early) {1251 dev_dbg(dev, "postponing D0 transition to normal resume stage\n");1252 return 0;1253 }1254 1255 ret = acpi_dev_resume(dev);1256 return ret ? ret : pm_generic_resume_early(dev);1257}1258 1259/**1260 * acpi_subsys_resume - Resume device using ACPI.1261 * @dev: Device to Resume.1262 *1263 * Use ACPI to put the given device into the full-power state if it has not been1264 * powered up during early resume phase, and carry out the generic resume1265 * procedure for it during system transition into the working state.1266 */1267static int acpi_subsys_resume(struct device *dev)1268{1269 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;1270 int ret = 0;1271 1272 if (!dev_pm_skip_resume(dev) && pm && !pm->resume_early) {1273 dev_dbg(dev, "executing postponed D0 transition\n");1274 ret = acpi_dev_resume(dev);1275 }1276 1277 return ret ? ret : pm_generic_resume(dev);1278}1279 1280/**1281 * acpi_subsys_freeze - Run the device driver's freeze callback.1282 * @dev: Device to handle.1283 */1284int acpi_subsys_freeze(struct device *dev)1285{1286 /*1287 * Resume all runtime-suspended devices before creating a snapshot1288 * image of system memory, because the restore kernel generally cannot1289 * be expected to always handle them consistently and they need to be1290 * put into the runtime-active metastate during system resume anyway,1291 * so it is better to ensure that the state saved in the image will be1292 * always consistent with that.1293 */1294 pm_runtime_resume(dev);1295 1296 return pm_generic_freeze(dev);1297}1298EXPORT_SYMBOL_GPL(acpi_subsys_freeze);1299 1300/**1301 * acpi_subsys_restore_early - Restore device using ACPI.1302 * @dev: Device to restore.1303 */1304int acpi_subsys_restore_early(struct device *dev)1305{1306 int ret = acpi_dev_resume(dev);1307 1308 return ret ? ret : pm_generic_restore_early(dev);1309}1310EXPORT_SYMBOL_GPL(acpi_subsys_restore_early);1311 1312/**1313 * acpi_subsys_poweroff - Run the device driver's poweroff callback.1314 * @dev: Device to handle.1315 *1316 * Follow PCI and resume devices from runtime suspend before running their1317 * system poweroff callbacks, unless the driver can cope with runtime-suspended1318 * devices during system suspend and there are no ACPI-specific reasons for1319 * resuming them.1320 */1321int acpi_subsys_poweroff(struct device *dev)1322{1323 if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||1324 acpi_dev_needs_resume(dev, ACPI_COMPANION(dev)))1325 pm_runtime_resume(dev);1326 1327 return pm_generic_poweroff(dev);1328}1329EXPORT_SYMBOL_GPL(acpi_subsys_poweroff);1330 1331/**1332 * acpi_subsys_poweroff_late - Run the device driver's poweroff callback.1333 * @dev: Device to handle.1334 *1335 * Carry out the generic late poweroff procedure for @dev and use ACPI to put1336 * it into a low-power state during system transition into a sleep state.1337 */1338static int acpi_subsys_poweroff_late(struct device *dev)1339{1340 int ret;1341 1342 if (dev_pm_skip_suspend(dev))1343 return 0;1344 1345 ret = pm_generic_poweroff_late(dev);1346 if (ret)1347 return ret;1348 1349 return acpi_dev_suspend(dev, device_may_wakeup(dev));1350}1351 1352/**1353 * acpi_subsys_poweroff_noirq - Run the driver's "noirq" poweroff callback.1354 * @dev: Device to suspend.1355 */1356static int acpi_subsys_poweroff_noirq(struct device *dev)1357{1358 if (dev_pm_skip_suspend(dev))1359 return 0;1360 1361 return pm_generic_poweroff_noirq(dev);1362}1363#endif /* CONFIG_PM_SLEEP */1364 1365static struct dev_pm_domain acpi_general_pm_domain = {1366 .ops = {1367 .runtime_suspend = acpi_subsys_runtime_suspend,1368 .runtime_resume = acpi_subsys_runtime_resume,1369#ifdef CONFIG_PM_SLEEP1370 .prepare = acpi_subsys_prepare,1371 .complete = acpi_subsys_complete,1372 .suspend = acpi_subsys_suspend,1373 .resume = acpi_subsys_resume,1374 .suspend_late = acpi_subsys_suspend_late,1375 .suspend_noirq = acpi_subsys_suspend_noirq,1376 .resume_noirq = acpi_subsys_resume_noirq,1377 .resume_early = acpi_subsys_resume_early,1378 .freeze = acpi_subsys_freeze,1379 .poweroff = acpi_subsys_poweroff,1380 .poweroff_late = acpi_subsys_poweroff_late,1381 .poweroff_noirq = acpi_subsys_poweroff_noirq,1382 .restore_early = acpi_subsys_restore_early,1383#endif1384 },1385};1386 1387/**1388 * acpi_dev_pm_detach - Remove ACPI power management from the device.1389 * @dev: Device to take care of.1390 * @power_off: Whether or not to try to remove power from the device.1391 *1392 * Remove the device from the general ACPI PM domain and remove its wakeup1393 * notifier. If @power_off is set, additionally remove power from the device if1394 * possible.1395 *1396 * Callers must ensure proper synchronization of this function with power1397 * management callbacks.1398 */1399static void acpi_dev_pm_detach(struct device *dev, bool power_off)1400{1401 struct acpi_device *adev = ACPI_COMPANION(dev);1402 1403 if (adev && dev->pm_domain == &acpi_general_pm_domain) {1404 dev_pm_domain_set(dev, NULL);1405 acpi_remove_pm_notifier(adev);1406 if (power_off) {1407 /*1408 * If the device's PM QoS resume latency limit or flags1409 * have been exposed to user space, they have to be1410 * hidden at this point, so that they don't affect the1411 * choice of the low-power state to put the device into.1412 */1413 dev_pm_qos_hide_latency_limit(dev);1414 dev_pm_qos_hide_flags(dev);1415 acpi_device_wakeup_disable(adev);1416 acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);1417 }1418 }1419}1420 1421/**1422 * acpi_dev_pm_attach - Prepare device for ACPI power management.1423 * @dev: Device to prepare.1424 * @power_on: Whether or not to power on the device.1425 *1426 * If @dev has a valid ACPI handle that has a valid struct acpi_device object1427 * attached to it, install a wakeup notification handler for the device and1428 * add it to the general ACPI PM domain. If @power_on is set, the device will1429 * be put into the ACPI D0 state before the function returns.1430 *1431 * This assumes that the @dev's bus type uses generic power management callbacks1432 * (or doesn't use any power management callbacks at all).1433 *1434 * Callers must ensure proper synchronization of this function with power1435 * management callbacks.1436 */1437int acpi_dev_pm_attach(struct device *dev, bool power_on)1438{1439 /*1440 * Skip devices whose ACPI companions match the device IDs below,1441 * because they require special power management handling incompatible1442 * with the generic ACPI PM domain.1443 */1444 static const struct acpi_device_id special_pm_ids[] = {1445 ACPI_FAN_DEVICE_IDS,1446 {}1447 };1448 struct acpi_device *adev = ACPI_COMPANION(dev);1449 1450 if (!adev || !acpi_match_device_ids(adev, special_pm_ids))1451 return 0;1452 1453 /*1454 * Only attach the power domain to the first device if the1455 * companion is shared by multiple. This is to prevent doing power1456 * management twice.1457 */1458 if (!acpi_device_is_first_physical_node(adev, dev))1459 return 0;1460 1461 acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func);1462 dev_pm_domain_set(dev, &acpi_general_pm_domain);1463 if (power_on) {1464 acpi_dev_pm_full_power(adev);1465 acpi_device_wakeup_disable(adev);1466 }1467 1468 dev->pm_domain->detach = acpi_dev_pm_detach;1469 return 1;1470}1471EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);1472 1473/**1474 * acpi_storage_d3 - Check if D3 should be used in the suspend path1475 * @dev: Device to check1476 *1477 * Return %true if the platform firmware wants @dev to be programmed1478 * into D3hot or D3cold (if supported) in the suspend path, or %false1479 * when there is no specific preference. On some platforms, if this1480 * hint is ignored, @dev may remain unresponsive after suspending the1481 * platform as a whole.1482 *1483 * Although the property has storage in the name it actually is1484 * applied to the PCIe slot and plugging in a non-storage device the1485 * same platform restrictions will likely apply.1486 */1487bool acpi_storage_d3(struct device *dev)1488{1489 struct acpi_device *adev = ACPI_COMPANION(dev);1490 u8 val;1491 1492 if (force_storage_d3())1493 return true;1494 1495 if (!adev)1496 return false;1497 if (fwnode_property_read_u8(acpi_fwnode_handle(adev), "StorageD3Enable",1498 &val))1499 return false;1500 return val == 1;1501}1502EXPORT_SYMBOL_GPL(acpi_storage_d3);1503 1504/**1505 * acpi_dev_state_d0 - Tell if the device is in D0 power state1506 * @dev: Physical device the ACPI power state of which to check1507 *1508 * On a system without ACPI, return true. On a system with ACPI, return true if1509 * the current ACPI power state of the device is D0, or false otherwise.1510 *1511 * Note that the power state of a device is not well-defined after it has been1512 * passed to acpi_device_set_power() and before that function returns, so it is1513 * not valid to ask for the ACPI power state of the device in that time frame.1514 *1515 * This function is intended to be used in a driver's probe or remove1516 * function. See Documentation/firmware-guide/acpi/non-d0-probe.rst for1517 * more information.1518 */1519bool acpi_dev_state_d0(struct device *dev)1520{1521 struct acpi_device *adev = ACPI_COMPANION(dev);1522 1523 if (!adev)1524 return true;1525 1526 return adev->power.state == ACPI_STATE_D0;1527}1528EXPORT_SYMBOL_GPL(acpi_dev_state_d0);1529 1530#endif /* CONFIG_PM */1531