1 // SPDX-License-Identifier: GPL-2.0-only
3 * drivers/acpi/device_pm.c - ACPI device power management routines.
5 * Copyright (C) 2012, Intel Corp.
6 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
8 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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>
23 #define _COMPONENT ACPI_POWER_COMPONENT
24 ACPI_MODULE_NAME("device_pm");
27 * acpi_power_state_string - String representation of ACPI device power state.
28 * @state: ACPI device power state to return the string representation of.
30 const char *acpi_power_state_string(int state)
39 case ACPI_STATE_D3_HOT:
41 case ACPI_STATE_D3_COLD:
48 static int acpi_dev_pm_explicit_get(struct acpi_device *device, int *state)
50 unsigned long long psc;
53 status = acpi_evaluate_integer(device->handle, "_PSC", NULL, &psc);
54 if (ACPI_FAILURE(status))
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.
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).
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).
75 int acpi_device_get_power(struct acpi_device *device, int *state)
77 int result = ACPI_STATE_UNKNOWN;
80 if (!device || !state)
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;
91 * Get the device's power state from power resources settings and _PSC,
94 if (device->power.flags.power_resources) {
95 error = acpi_power_get_inferred_state(device, &result);
99 if (device->power.flags.explicit_get) {
102 error = acpi_dev_pm_explicit_get(device, &psc);
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.
111 * For systems predating ACPI 4.0 we assume that D3hot is the
112 * deepest state that can be supported.
114 if (psc > result && psc < ACPI_STATE_D3_COLD)
116 else if (result == ACPI_STATE_UNKNOWN)
117 result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_HOT : psc;
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.
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;
133 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n",
134 device->pnp.bus_id, acpi_power_state_string(*state)));
139 static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state)
141 if (adev->power.states[state].flags.explicit_set) {
142 char method[5] = { '_', 'P', 'S', '0' + state, '\0' };
145 status = acpi_evaluate_object(adev->handle, method, NULL, NULL);
146 if (ACPI_FAILURE(status))
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.
157 * Callers must ensure that the device is power manageable before using this
160 int acpi_device_set_power(struct acpi_device *device, int state)
162 int target_state = state;
165 if (!device || !device->flags.power_manageable
166 || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
169 /* Make sure this is a valid target state */
171 /* There is a special case for D0 addressed below. */
172 if (state > ACPI_STATE_D0 && state == device->power.state) {
173 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already in %s\n",
175 acpi_power_state_string(state)));
179 if (state == ACPI_STATE_D3_COLD) {
181 * For transitions to D3cold we need to execute _PS3 and then
182 * possibly drop references to the power resources in use.
184 state = ACPI_STATE_D3_HOT;
185 /* If _PR3 is not available, use D3hot as the target state. */
186 if (!device->power.states[ACPI_STATE_D3_COLD].flags.valid)
187 target_state = state;
188 } else if (!device->power.states[state].flags.valid) {
189 dev_warn(&device->dev, "Power state %s not supported\n",
190 acpi_power_state_string(state));
194 if (!device->power.flags.ignore_parent &&
195 device->parent && (state < device->parent->power.state)) {
196 dev_warn(&device->dev,
197 "Cannot transition to power state %s for parent in %s\n",
198 acpi_power_state_string(state),
199 acpi_power_state_string(device->parent->power.state));
206 * In accordance with ACPI 6, _PSx is executed before manipulating power
207 * resources, unless the target state is D0, in which case _PS0 is
208 * supposed to be executed after turning the power resources on.
210 if (state > ACPI_STATE_D0) {
212 * According to ACPI 6, devices cannot go from lower-power
213 * (deeper) states to higher-power (shallower) states.
215 if (state < device->power.state) {
216 dev_warn(&device->dev, "Cannot transition from %s to %s\n",
217 acpi_power_state_string(device->power.state),
218 acpi_power_state_string(state));
223 * If the device goes from D3hot to D3cold, _PS3 has been
224 * evaluated for it already, so skip it in that case.
226 if (device->power.state < ACPI_STATE_D3_HOT) {
227 result = acpi_dev_pm_explicit_set(device, state);
232 if (device->power.flags.power_resources)
233 result = acpi_power_transition(device, target_state);
235 int cur_state = device->power.state;
237 if (device->power.flags.power_resources) {
238 result = acpi_power_transition(device, ACPI_STATE_D0);
243 if (cur_state == ACPI_STATE_D0) {
246 /* Nothing to do here if _PSC is not present. */
247 if (!device->power.flags.explicit_get)
251 * The power state of the device was set to D0 last
252 * time, but that might have happened before a
253 * system-wide transition involving the platform
254 * firmware, so it may be necessary to evaluate _PS0
255 * for the device here. However, use extra care here
256 * and evaluate _PSC to check the device's current power
257 * state, and only invoke _PS0 if the evaluation of _PSC
258 * is successful and it returns a power state different
261 result = acpi_dev_pm_explicit_get(device, &psc);
262 if (result || psc == ACPI_STATE_D0)
266 result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
271 dev_warn(&device->dev, "Failed to change power state to %s\n",
272 acpi_power_state_string(state));
274 device->power.state = target_state;
275 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
276 "Device [%s] transitioned to %s\n",
278 acpi_power_state_string(state)));
283 EXPORT_SYMBOL(acpi_device_set_power);
285 int acpi_bus_set_power(acpi_handle handle, int state)
287 struct acpi_device *device;
290 result = acpi_bus_get_device(handle, &device);
294 return acpi_device_set_power(device, state);
296 EXPORT_SYMBOL(acpi_bus_set_power);
298 int acpi_bus_init_power(struct acpi_device *device)
306 device->power.state = ACPI_STATE_UNKNOWN;
307 if (!acpi_device_is_present(device)) {
308 device->flags.initialized = false;
312 result = acpi_device_get_power(device, &state);
316 if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {
317 /* Reference count the power resources. */
318 result = acpi_power_on_resources(device, state);
322 if (state == ACPI_STATE_D0) {
324 * If _PSC is not present and the state inferred from
325 * power resources appears to be D0, it still may be
326 * necessary to execute _PS0 at this point, because
327 * another device using the same power resources may
328 * have been put into D0 previously and that's why we
331 result = acpi_dev_pm_explicit_set(device, state);
335 } else if (state == ACPI_STATE_UNKNOWN) {
337 * No power resources and missing _PSC? Cross fingers and make
338 * it D0 in hope that this is what the BIOS put the device into.
339 * [We tried to force D0 here by executing _PS0, but that broke
340 * Toshiba P870-303 in a nasty way.]
342 state = ACPI_STATE_D0;
344 device->power.state = state;
349 * acpi_device_fix_up_power - Force device with missing _PSC into D0.
350 * @device: Device object whose power state is to be fixed up.
352 * Devices without power resources and _PSC, but having _PS0 and _PS3 defined,
353 * are assumed to be put into D0 by the BIOS. However, in some cases that may
354 * not be the case and this function should be used then.
356 int acpi_device_fix_up_power(struct acpi_device *device)
360 if (!device->power.flags.power_resources
361 && !device->power.flags.explicit_get
362 && device->power.state == ACPI_STATE_D0)
363 ret = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
367 EXPORT_SYMBOL_GPL(acpi_device_fix_up_power);
369 int acpi_device_update_power(struct acpi_device *device, int *state_p)
374 if (device->power.state == ACPI_STATE_UNKNOWN) {
375 result = acpi_bus_init_power(device);
376 if (!result && state_p)
377 *state_p = device->power.state;
382 result = acpi_device_get_power(device, &state);
386 if (state == ACPI_STATE_UNKNOWN) {
387 state = ACPI_STATE_D0;
388 result = acpi_device_set_power(device, state);
392 if (device->power.flags.power_resources) {
394 * We don't need to really switch the state, bu we need
395 * to update the power resources' reference counters.
397 result = acpi_power_transition(device, state);
401 device->power.state = state;
408 EXPORT_SYMBOL_GPL(acpi_device_update_power);
410 int acpi_bus_update_power(acpi_handle handle, int *state_p)
412 struct acpi_device *device;
415 result = acpi_bus_get_device(handle, &device);
416 return result ? result : acpi_device_update_power(device, state_p);
418 EXPORT_SYMBOL_GPL(acpi_bus_update_power);
420 bool acpi_bus_power_manageable(acpi_handle handle)
422 struct acpi_device *device;
425 result = acpi_bus_get_device(handle, &device);
426 return result ? false : device->flags.power_manageable;
428 EXPORT_SYMBOL(acpi_bus_power_manageable);
431 static DEFINE_MUTEX(acpi_pm_notifier_lock);
432 static DEFINE_MUTEX(acpi_pm_notifier_install_lock);
434 void acpi_pm_wakeup_event(struct device *dev)
436 pm_wakeup_dev_event(dev, 0, acpi_s2idle_wakeup());
438 EXPORT_SYMBOL_GPL(acpi_pm_wakeup_event);
440 static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used)
442 struct acpi_device *adev;
444 if (val != ACPI_NOTIFY_DEVICE_WAKE)
447 acpi_handle_debug(handle, "Wake notify\n");
449 adev = acpi_bus_get_acpi_device(handle);
453 mutex_lock(&acpi_pm_notifier_lock);
455 if (adev->wakeup.flags.notifier_present) {
456 pm_wakeup_ws_event(adev->wakeup.ws, 0, acpi_s2idle_wakeup());
457 if (adev->wakeup.context.func) {
458 acpi_handle_debug(handle, "Running %pS for %s\n",
459 adev->wakeup.context.func,
460 dev_name(adev->wakeup.context.dev));
461 adev->wakeup.context.func(&adev->wakeup.context);
465 mutex_unlock(&acpi_pm_notifier_lock);
467 acpi_bus_put_acpi_device(adev);
471 * acpi_add_pm_notifier - Register PM notify handler for given ACPI device.
472 * @adev: ACPI device to add the notify handler for.
473 * @dev: Device to generate a wakeup event for while handling the notification.
474 * @func: Work function to execute when handling the notification.
476 * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of
477 * PM wakeup events. For example, wakeup events may be generated for bridges
478 * if one of the devices below the bridge is signaling wakeup, even if the
479 * bridge itself doesn't have a wakeup GPE associated with it.
481 acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev,
482 void (*func)(struct acpi_device_wakeup_context *context))
484 acpi_status status = AE_ALREADY_EXISTS;
487 return AE_BAD_PARAMETER;
489 mutex_lock(&acpi_pm_notifier_install_lock);
491 if (adev->wakeup.flags.notifier_present)
494 status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY,
495 acpi_pm_notify_handler, NULL);
496 if (ACPI_FAILURE(status))
499 mutex_lock(&acpi_pm_notifier_lock);
500 adev->wakeup.ws = wakeup_source_register(&adev->dev,
501 dev_name(&adev->dev));
502 adev->wakeup.context.dev = dev;
503 adev->wakeup.context.func = func;
504 adev->wakeup.flags.notifier_present = true;
505 mutex_unlock(&acpi_pm_notifier_lock);
508 mutex_unlock(&acpi_pm_notifier_install_lock);
513 * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
514 * @adev: ACPI device to remove the notifier from.
516 acpi_status acpi_remove_pm_notifier(struct acpi_device *adev)
518 acpi_status status = AE_BAD_PARAMETER;
520 mutex_lock(&acpi_pm_notifier_install_lock);
522 if (!adev->wakeup.flags.notifier_present)
525 status = acpi_remove_notify_handler(adev->handle,
527 acpi_pm_notify_handler);
528 if (ACPI_FAILURE(status))
531 mutex_lock(&acpi_pm_notifier_lock);
532 adev->wakeup.context.func = NULL;
533 adev->wakeup.context.dev = NULL;
534 wakeup_source_unregister(adev->wakeup.ws);
535 adev->wakeup.flags.notifier_present = false;
536 mutex_unlock(&acpi_pm_notifier_lock);
539 mutex_unlock(&acpi_pm_notifier_install_lock);
543 bool acpi_bus_can_wakeup(acpi_handle handle)
545 struct acpi_device *device;
548 result = acpi_bus_get_device(handle, &device);
549 return result ? false : device->wakeup.flags.valid;
551 EXPORT_SYMBOL(acpi_bus_can_wakeup);
553 bool acpi_pm_device_can_wakeup(struct device *dev)
555 struct acpi_device *adev = ACPI_COMPANION(dev);
557 return adev ? acpi_device_can_wakeup(adev) : false;
561 * acpi_dev_pm_get_state - Get preferred power state of ACPI device.
562 * @dev: Device whose preferred target power state to return.
563 * @adev: ACPI device node corresponding to @dev.
564 * @target_state: System state to match the resultant device state.
565 * @d_min_p: Location to store the highest power state available to the device.
566 * @d_max_p: Location to store the lowest power state available to the device.
568 * Find the lowest power (highest number) and highest power (lowest number) ACPI
569 * device power states that the device can be in while the system is in the
570 * state represented by @target_state. Store the integer numbers representing
571 * those stats in the memory locations pointed to by @d_max_p and @d_min_p,
574 * Callers must ensure that @dev and @adev are valid pointers and that @adev
575 * actually corresponds to @dev before using this function.
577 * Returns 0 on success or -ENODATA when one of the ACPI methods fails or
578 * returns a value that doesn't make sense. The memory locations pointed to by
579 * @d_max_p and @d_min_p are only modified on success.
581 static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev,
582 u32 target_state, int *d_min_p, int *d_max_p)
584 char method[] = { '_', 'S', '0' + target_state, 'D', '\0' };
585 acpi_handle handle = adev->handle;
586 unsigned long long ret;
589 bool has_sxd = false;
593 * If the system state is S0, the lowest power state the device can be
594 * in is D3cold, unless the device has _S0W and is supposed to signal
595 * wakeup, in which case the return value of _S0W has to be used as the
596 * lowest power state available to the device.
598 d_min = ACPI_STATE_D0;
599 d_max = ACPI_STATE_D3_COLD;
602 * If present, _SxD methods return the minimum D-state (highest power
603 * state) we can use for the corresponding S-states. Otherwise, the
604 * minimum D-state is D0 (ACPI 3.x).
606 if (target_state > ACPI_STATE_S0) {
608 * We rely on acpi_evaluate_integer() not clobbering the integer
609 * provided if AE_NOT_FOUND is returned.
612 status = acpi_evaluate_integer(handle, method, NULL, &ret);
613 if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND)
614 || ret > ACPI_STATE_D3_COLD)
618 * We need to handle legacy systems where D3hot and D3cold are
619 * the same and 3 is returned in both cases, so fall back to
620 * D3cold if D3hot is not a valid state.
622 if (!adev->power.states[ret].flags.valid) {
623 if (ret == ACPI_STATE_D3_HOT)
624 ret = ACPI_STATE_D3_COLD;
633 wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
634 && adev->wakeup.sleep_state >= target_state;
636 wakeup = adev->wakeup.flags.valid;
640 * If _PRW says we can wake up the system from the target sleep state,
641 * the D-state returned by _SxD is sufficient for that (we assume a
642 * wakeup-aware driver if wake is set). Still, if _SxW exists
643 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
644 * can wake the system. _S0W may be valid, too.
648 status = acpi_evaluate_integer(handle, method, NULL, &ret);
649 if (status == AE_NOT_FOUND) {
650 /* No _SxW. In this case, the ACPI spec says that we
651 * must not go into any power state deeper than the
652 * value returned from _SxD.
654 if (has_sxd && target_state > ACPI_STATE_S0)
656 } else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) {
657 /* Fall back to D3cold if ret is not a valid state. */
658 if (!adev->power.states[ret].flags.valid)
659 ret = ACPI_STATE_D3_COLD;
661 d_max = ret > d_min ? ret : d_min;
677 * acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
678 * @dev: Device whose preferred target power state to return.
679 * @d_min_p: Location to store the upper limit of the allowed states range.
680 * @d_max_in: Deepest low-power state to take into consideration.
681 * Return value: Preferred power state of the device on success, -ENODEV
682 * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is
683 * incorrect, or -ENODATA on ACPI method failure.
685 * The caller must ensure that @dev is valid before using this function.
687 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
689 struct acpi_device *adev;
690 int ret, d_min, d_max;
692 if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD)
695 if (d_max_in > ACPI_STATE_D2) {
696 enum pm_qos_flags_status stat;
698 stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
699 if (stat == PM_QOS_FLAGS_ALL)
700 d_max_in = ACPI_STATE_D2;
703 adev = ACPI_COMPANION(dev);
705 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
709 ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(),
714 if (d_max_in < d_min)
717 if (d_max > d_max_in) {
718 for (d_max = d_max_in; d_max > d_min; d_max--) {
719 if (adev->power.states[d_max].flags.valid)
729 EXPORT_SYMBOL(acpi_pm_device_sleep_state);
732 * acpi_pm_notify_work_func - ACPI devices wakeup notification work function.
733 * @context: Device wakeup context.
735 static void acpi_pm_notify_work_func(struct acpi_device_wakeup_context *context)
737 struct device *dev = context->dev;
740 pm_wakeup_event(dev, 0);
741 pm_request_resume(dev);
745 static DEFINE_MUTEX(acpi_wakeup_lock);
747 static int __acpi_device_wakeup_enable(struct acpi_device *adev,
748 u32 target_state, int max_count)
750 struct acpi_device_wakeup *wakeup = &adev->wakeup;
754 mutex_lock(&acpi_wakeup_lock);
756 if (wakeup->enable_count >= max_count)
759 if (wakeup->enable_count > 0)
762 error = acpi_enable_wakeup_device_power(adev, target_state);
766 status = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
767 if (ACPI_FAILURE(status)) {
768 acpi_disable_wakeup_device_power(adev);
773 acpi_handle_debug(adev->handle, "GPE%2X enabled for wakeup\n",
774 (unsigned int)wakeup->gpe_number);
777 wakeup->enable_count++;
780 mutex_unlock(&acpi_wakeup_lock);
785 * acpi_device_wakeup_enable - Enable wakeup functionality for device.
786 * @adev: ACPI device to enable wakeup functionality for.
787 * @target_state: State the system is transitioning into.
789 * Enable the GPE associated with @adev so that it can generate wakeup signals
790 * for the device in response to external (remote) events and enable wakeup
793 * Callers must ensure that @adev is a valid ACPI device node before executing
796 static int acpi_device_wakeup_enable(struct acpi_device *adev, u32 target_state)
798 return __acpi_device_wakeup_enable(adev, target_state, 1);
802 * acpi_device_wakeup_disable - Disable wakeup functionality for device.
803 * @adev: ACPI device to disable wakeup functionality for.
805 * Disable the GPE associated with @adev and disable wakeup power for it.
807 * Callers must ensure that @adev is a valid ACPI device node before executing
810 static void acpi_device_wakeup_disable(struct acpi_device *adev)
812 struct acpi_device_wakeup *wakeup = &adev->wakeup;
814 mutex_lock(&acpi_wakeup_lock);
816 if (!wakeup->enable_count)
819 acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
820 acpi_disable_wakeup_device_power(adev);
822 wakeup->enable_count--;
825 mutex_unlock(&acpi_wakeup_lock);
828 static int __acpi_pm_set_device_wakeup(struct device *dev, bool enable,
831 struct acpi_device *adev;
834 adev = ACPI_COMPANION(dev);
836 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
840 if (!acpi_device_can_wakeup(adev))
844 acpi_device_wakeup_disable(adev);
845 dev_dbg(dev, "Wakeup disabled by ACPI\n");
849 error = __acpi_device_wakeup_enable(adev, acpi_target_system_state(),
852 dev_dbg(dev, "Wakeup enabled by ACPI\n");
858 * acpi_pm_set_device_wakeup - Enable/disable remote wakeup for given device.
859 * @dev: Device to enable/disable to generate wakeup events.
860 * @enable: Whether to enable or disable the wakeup functionality.
862 int acpi_pm_set_device_wakeup(struct device *dev, bool enable)
864 return __acpi_pm_set_device_wakeup(dev, enable, 1);
866 EXPORT_SYMBOL_GPL(acpi_pm_set_device_wakeup);
869 * acpi_pm_set_bridge_wakeup - Enable/disable remote wakeup for given bridge.
870 * @dev: Bridge device to enable/disable to generate wakeup events.
871 * @enable: Whether to enable or disable the wakeup functionality.
873 int acpi_pm_set_bridge_wakeup(struct device *dev, bool enable)
875 return __acpi_pm_set_device_wakeup(dev, enable, INT_MAX);
877 EXPORT_SYMBOL_GPL(acpi_pm_set_bridge_wakeup);
880 * acpi_dev_pm_low_power - Put ACPI device into a low-power state.
881 * @dev: Device to put into a low-power state.
882 * @adev: ACPI device node corresponding to @dev.
883 * @system_state: System state to choose the device state for.
885 static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev,
890 if (!acpi_device_power_manageable(adev))
893 ret = acpi_dev_pm_get_state(dev, adev, system_state, NULL, &state);
894 return ret ? ret : acpi_device_set_power(adev, state);
898 * acpi_dev_pm_full_power - Put ACPI device into the full-power state.
899 * @adev: ACPI device node to put into the full-power state.
901 static int acpi_dev_pm_full_power(struct acpi_device *adev)
903 return acpi_device_power_manageable(adev) ?
904 acpi_device_set_power(adev, ACPI_STATE_D0) : 0;
908 * acpi_dev_suspend - Put device into a low-power state using ACPI.
909 * @dev: Device to put into a low-power state.
910 * @wakeup: Whether or not to enable wakeup for the device.
912 * Put the given device into a low-power state using the standard ACPI
913 * mechanism. Set up remote wakeup if desired, choose the state to put the
914 * device into (this checks if remote wakeup is expected to work too), and set
915 * the power state of the device.
917 int acpi_dev_suspend(struct device *dev, bool wakeup)
919 struct acpi_device *adev = ACPI_COMPANION(dev);
920 u32 target_state = acpi_target_system_state();
926 if (wakeup && acpi_device_can_wakeup(adev)) {
927 error = acpi_device_wakeup_enable(adev, target_state);
934 error = acpi_dev_pm_low_power(dev, adev, target_state);
936 acpi_device_wakeup_disable(adev);
940 EXPORT_SYMBOL_GPL(acpi_dev_suspend);
943 * acpi_dev_resume - Put device into the full-power state using ACPI.
944 * @dev: Device to put into the full-power state.
946 * Put the given device into the full-power state using the standard ACPI
947 * mechanism. Set the power state of the device to ACPI D0 and disable wakeup.
949 int acpi_dev_resume(struct device *dev)
951 struct acpi_device *adev = ACPI_COMPANION(dev);
957 error = acpi_dev_pm_full_power(adev);
958 acpi_device_wakeup_disable(adev);
961 EXPORT_SYMBOL_GPL(acpi_dev_resume);
964 * acpi_subsys_runtime_suspend - Suspend device using ACPI.
965 * @dev: Device to suspend.
967 * Carry out the generic runtime suspend procedure for @dev and use ACPI to put
968 * it into a runtime low-power state.
970 int acpi_subsys_runtime_suspend(struct device *dev)
972 int ret = pm_generic_runtime_suspend(dev);
973 return ret ? ret : acpi_dev_suspend(dev, true);
975 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);
978 * acpi_subsys_runtime_resume - Resume device using ACPI.
979 * @dev: Device to Resume.
981 * Use ACPI to put the given device into the full-power state and carry out the
982 * generic runtime resume procedure for it.
984 int acpi_subsys_runtime_resume(struct device *dev)
986 int ret = acpi_dev_resume(dev);
987 return ret ? ret : pm_generic_runtime_resume(dev);
989 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
991 #ifdef CONFIG_PM_SLEEP
992 static bool acpi_dev_needs_resume(struct device *dev, struct acpi_device *adev)
994 u32 sys_target = acpi_target_system_state();
997 if (!pm_runtime_suspended(dev) || !adev || (adev->wakeup.flags.valid &&
998 device_may_wakeup(dev) != !!adev->wakeup.prepare_count))
1001 if (sys_target == ACPI_STATE_S0)
1004 if (adev->power.flags.dsw_present)
1007 ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state);
1011 return state != adev->power.state;
1015 * acpi_subsys_prepare - Prepare device for system transition to a sleep state.
1016 * @dev: Device to prepare.
1018 int acpi_subsys_prepare(struct device *dev)
1020 struct acpi_device *adev = ACPI_COMPANION(dev);
1022 if (dev->driver && dev->driver->pm && dev->driver->pm->prepare) {
1023 int ret = dev->driver->pm->prepare(dev);
1028 if (!ret && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))
1032 return !acpi_dev_needs_resume(dev, adev);
1034 EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
1037 * acpi_subsys_complete - Finalize device's resume during system resume.
1038 * @dev: Device to handle.
1040 void acpi_subsys_complete(struct device *dev)
1042 pm_generic_complete(dev);
1044 * If the device had been runtime-suspended before the system went into
1045 * the sleep state it is going out of and it has never been resumed till
1046 * now, resume it in case the firmware powered it up.
1048 if (pm_runtime_suspended(dev) && pm_resume_via_firmware())
1049 pm_request_resume(dev);
1051 EXPORT_SYMBOL_GPL(acpi_subsys_complete);
1054 * acpi_subsys_suspend - Run the device driver's suspend callback.
1055 * @dev: Device to handle.
1057 * Follow PCI and resume devices from runtime suspend before running their
1058 * system suspend callbacks, unless the driver can cope with runtime-suspended
1059 * devices during system suspend and there are no ACPI-specific reasons for
1062 int acpi_subsys_suspend(struct device *dev)
1064 if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
1065 acpi_dev_needs_resume(dev, ACPI_COMPANION(dev)))
1066 pm_runtime_resume(dev);
1068 return pm_generic_suspend(dev);
1070 EXPORT_SYMBOL_GPL(acpi_subsys_suspend);
1073 * acpi_subsys_suspend_late - Suspend device using ACPI.
1074 * @dev: Device to suspend.
1076 * Carry out the generic late suspend procedure for @dev and use ACPI to put
1077 * it into a low-power state during system transition into a sleep state.
1079 int acpi_subsys_suspend_late(struct device *dev)
1083 if (dev_pm_smart_suspend_and_suspended(dev))
1086 ret = pm_generic_suspend_late(dev);
1087 return ret ? ret : acpi_dev_suspend(dev, device_may_wakeup(dev));
1089 EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
1092 * acpi_subsys_suspend_noirq - Run the device driver's "noirq" suspend callback.
1093 * @dev: Device to suspend.
1095 int acpi_subsys_suspend_noirq(struct device *dev)
1099 if (dev_pm_smart_suspend_and_suspended(dev)) {
1100 dev->power.may_skip_resume = true;
1104 ret = pm_generic_suspend_noirq(dev);
1109 * If the target system sleep state is suspend-to-idle, it is sufficient
1110 * to check whether or not the device's wakeup settings are good for
1111 * runtime PM. Otherwise, the pm_resume_via_firmware() check will cause
1112 * acpi_subsys_complete() to take care of fixing up the device's state
1113 * anyway, if need be.
1115 dev->power.may_skip_resume = device_may_wakeup(dev) ||
1116 !device_can_wakeup(dev);
1120 EXPORT_SYMBOL_GPL(acpi_subsys_suspend_noirq);
1123 * acpi_subsys_resume_noirq - Run the device driver's "noirq" resume callback.
1124 * @dev: Device to handle.
1126 static int acpi_subsys_resume_noirq(struct device *dev)
1128 if (dev_pm_may_skip_resume(dev))
1132 * Devices with DPM_FLAG_SMART_SUSPEND may be left in runtime suspend
1133 * during system suspend, so update their runtime PM status to "active"
1134 * as they will be put into D0 going forward.
1136 if (dev_pm_smart_suspend_and_suspended(dev))
1137 pm_runtime_set_active(dev);
1139 return pm_generic_resume_noirq(dev);
1143 * acpi_subsys_resume_early - Resume device using ACPI.
1144 * @dev: Device to Resume.
1146 * Use ACPI to put the given device into the full-power state and carry out the
1147 * generic early resume procedure for it during system transition into the
1150 static int acpi_subsys_resume_early(struct device *dev)
1152 int ret = acpi_dev_resume(dev);
1153 return ret ? ret : pm_generic_resume_early(dev);
1157 * acpi_subsys_freeze - Run the device driver's freeze callback.
1158 * @dev: Device to handle.
1160 int acpi_subsys_freeze(struct device *dev)
1163 * Resume all runtime-suspended devices before creating a snapshot
1164 * image of system memory, because the restore kernel generally cannot
1165 * be expected to always handle them consistently and they need to be
1166 * put into the runtime-active metastate during system resume anyway,
1167 * so it is better to ensure that the state saved in the image will be
1168 * always consistent with that.
1170 pm_runtime_resume(dev);
1172 return pm_generic_freeze(dev);
1174 EXPORT_SYMBOL_GPL(acpi_subsys_freeze);
1177 * acpi_subsys_restore_early - Restore device using ACPI.
1178 * @dev: Device to restore.
1180 int acpi_subsys_restore_early(struct device *dev)
1182 int ret = acpi_dev_resume(dev);
1183 return ret ? ret : pm_generic_restore_early(dev);
1185 EXPORT_SYMBOL_GPL(acpi_subsys_restore_early);
1188 * acpi_subsys_poweroff - Run the device driver's poweroff callback.
1189 * @dev: Device to handle.
1191 * Follow PCI and resume devices from runtime suspend before running their
1192 * system poweroff callbacks, unless the driver can cope with runtime-suspended
1193 * devices during system suspend and there are no ACPI-specific reasons for
1196 int acpi_subsys_poweroff(struct device *dev)
1198 if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
1199 acpi_dev_needs_resume(dev, ACPI_COMPANION(dev)))
1200 pm_runtime_resume(dev);
1202 return pm_generic_poweroff(dev);
1204 EXPORT_SYMBOL_GPL(acpi_subsys_poweroff);
1207 * acpi_subsys_poweroff_late - Run the device driver's poweroff callback.
1208 * @dev: Device to handle.
1210 * Carry out the generic late poweroff procedure for @dev and use ACPI to put
1211 * it into a low-power state during system transition into a sleep state.
1213 static int acpi_subsys_poweroff_late(struct device *dev)
1217 if (dev_pm_smart_suspend_and_suspended(dev))
1220 ret = pm_generic_poweroff_late(dev);
1224 return acpi_dev_suspend(dev, device_may_wakeup(dev));
1228 * acpi_subsys_poweroff_noirq - Run the driver's "noirq" poweroff callback.
1229 * @dev: Device to suspend.
1231 static int acpi_subsys_poweroff_noirq(struct device *dev)
1233 if (dev_pm_smart_suspend_and_suspended(dev))
1236 return pm_generic_poweroff_noirq(dev);
1238 #endif /* CONFIG_PM_SLEEP */
1240 static struct dev_pm_domain acpi_general_pm_domain = {
1242 .runtime_suspend = acpi_subsys_runtime_suspend,
1243 .runtime_resume = acpi_subsys_runtime_resume,
1244 #ifdef CONFIG_PM_SLEEP
1245 .prepare = acpi_subsys_prepare,
1246 .complete = acpi_subsys_complete,
1247 .suspend = acpi_subsys_suspend,
1248 .suspend_late = acpi_subsys_suspend_late,
1249 .suspend_noirq = acpi_subsys_suspend_noirq,
1250 .resume_noirq = acpi_subsys_resume_noirq,
1251 .resume_early = acpi_subsys_resume_early,
1252 .freeze = acpi_subsys_freeze,
1253 .poweroff = acpi_subsys_poweroff,
1254 .poweroff_late = acpi_subsys_poweroff_late,
1255 .poweroff_noirq = acpi_subsys_poweroff_noirq,
1256 .restore_early = acpi_subsys_restore_early,
1262 * acpi_dev_pm_detach - Remove ACPI power management from the device.
1263 * @dev: Device to take care of.
1264 * @power_off: Whether or not to try to remove power from the device.
1266 * Remove the device from the general ACPI PM domain and remove its wakeup
1267 * notifier. If @power_off is set, additionally remove power from the device if
1270 * Callers must ensure proper synchronization of this function with power
1271 * management callbacks.
1273 static void acpi_dev_pm_detach(struct device *dev, bool power_off)
1275 struct acpi_device *adev = ACPI_COMPANION(dev);
1277 if (adev && dev->pm_domain == &acpi_general_pm_domain) {
1278 dev_pm_domain_set(dev, NULL);
1279 acpi_remove_pm_notifier(adev);
1282 * If the device's PM QoS resume latency limit or flags
1283 * have been exposed to user space, they have to be
1284 * hidden at this point, so that they don't affect the
1285 * choice of the low-power state to put the device into.
1287 dev_pm_qos_hide_latency_limit(dev);
1288 dev_pm_qos_hide_flags(dev);
1289 acpi_device_wakeup_disable(adev);
1290 acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
1296 * acpi_dev_pm_attach - Prepare device for ACPI power management.
1297 * @dev: Device to prepare.
1298 * @power_on: Whether or not to power on the device.
1300 * If @dev has a valid ACPI handle that has a valid struct acpi_device object
1301 * attached to it, install a wakeup notification handler for the device and
1302 * add it to the general ACPI PM domain. If @power_on is set, the device will
1303 * be put into the ACPI D0 state before the function returns.
1305 * This assumes that the @dev's bus type uses generic power management callbacks
1306 * (or doesn't use any power management callbacks at all).
1308 * Callers must ensure proper synchronization of this function with power
1309 * management callbacks.
1311 int acpi_dev_pm_attach(struct device *dev, bool power_on)
1313 struct acpi_device *adev = ACPI_COMPANION(dev);
1319 * Only attach the power domain to the first device if the
1320 * companion is shared by multiple. This is to prevent doing power
1323 if (!acpi_device_is_first_physical_node(adev, dev))
1326 acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func);
1327 dev_pm_domain_set(dev, &acpi_general_pm_domain);
1329 acpi_dev_pm_full_power(adev);
1330 acpi_device_wakeup_disable(adev);
1333 dev->pm_domain->detach = acpi_dev_pm_detach;
1336 EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
1337 #endif /* CONFIG_PM */