2 * drivers/acpi/device_pm.c - ACPI device power management routines.
4 * Copyright (C) 2012, Intel Corp.
5 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as published
11 * by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
18 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
21 #include <linux/acpi.h>
22 #include <linux/export.h>
23 #include <linux/mutex.h>
24 #include <linux/pm_qos.h>
25 #include <linux/pm_domain.h>
26 #include <linux/pm_runtime.h>
27 #include <linux/suspend.h>
31 #define _COMPONENT ACPI_POWER_COMPONENT
32 ACPI_MODULE_NAME("device_pm");
35 * acpi_power_state_string - String representation of ACPI device power state.
36 * @state: ACPI device power state to return the string representation of.
38 const char *acpi_power_state_string(int state)
47 case ACPI_STATE_D3_HOT:
49 case ACPI_STATE_D3_COLD:
57 * acpi_device_get_power - Get power state of an ACPI device.
58 * @device: Device to get the power state of.
59 * @state: Place to store the power state of the device.
61 * This function does not update the device's power.state field, but it may
62 * update its parent's power.state field (when the parent's power state is
63 * unknown and the device's power state turns out to be D0).
65 int acpi_device_get_power(struct acpi_device *device, int *state)
67 int result = ACPI_STATE_UNKNOWN;
69 if (!device || !state)
72 if (!device->flags.power_manageable) {
73 /* TBD: Non-recursive algorithm for walking up hierarchy. */
74 *state = device->parent ?
75 device->parent->power.state : ACPI_STATE_D0;
80 * Get the device's power state from power resources settings and _PSC,
83 if (device->power.flags.power_resources) {
84 int error = acpi_power_get_inferred_state(device, &result);
88 if (device->power.flags.explicit_get) {
89 acpi_handle handle = device->handle;
90 unsigned long long psc;
93 status = acpi_evaluate_integer(handle, "_PSC", NULL, &psc);
94 if (ACPI_FAILURE(status))
98 * The power resources settings may indicate a power state
99 * shallower than the actual power state of the device, because
100 * the same power resources may be referenced by other devices.
102 * For systems predating ACPI 4.0 we assume that D3hot is the
103 * deepest state that can be supported.
105 if (psc > result && psc < ACPI_STATE_D3_COLD)
107 else if (result == ACPI_STATE_UNKNOWN)
108 result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_HOT : psc;
112 * If we were unsure about the device parent's power state up to this
113 * point, the fact that the device is in D0 implies that the parent has
114 * to be in D0 too, except if ignore_parent is set.
116 if (!device->power.flags.ignore_parent && device->parent
117 && device->parent->power.state == ACPI_STATE_UNKNOWN
118 && result == ACPI_STATE_D0)
119 device->parent->power.state = ACPI_STATE_D0;
124 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n",
125 device->pnp.bus_id, acpi_power_state_string(*state)));
129 EXPORT_SYMBOL(acpi_device_get_power);
131 static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state)
133 if (adev->power.states[state].flags.explicit_set) {
134 char method[5] = { '_', 'P', 'S', '0' + state, '\0' };
137 status = acpi_evaluate_object(adev->handle, method, NULL, NULL);
138 if (ACPI_FAILURE(status))
145 * acpi_device_set_power - Set power state of an ACPI device.
146 * @device: Device to set the power state of.
147 * @state: New power state to set.
149 * Callers must ensure that the device is power manageable before using this
152 int acpi_device_set_power(struct acpi_device *device, int state)
154 int target_state = state;
157 if (!device || !device->flags.power_manageable
158 || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
161 /* Make sure this is a valid target state */
163 if (state == device->power.state) {
164 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already in %s\n",
166 acpi_power_state_string(state)));
170 if (state == ACPI_STATE_D3_COLD) {
172 * For transitions to D3cold we need to execute _PS3 and then
173 * possibly drop references to the power resources in use.
175 state = ACPI_STATE_D3_HOT;
176 /* If _PR3 is not available, use D3hot as the target state. */
177 if (!device->power.states[ACPI_STATE_D3_COLD].flags.valid)
178 target_state = state;
179 } else if (!device->power.states[state].flags.valid) {
180 dev_warn(&device->dev, "Power state %s not supported\n",
181 acpi_power_state_string(state));
185 if (!device->power.flags.ignore_parent &&
186 device->parent && (state < device->parent->power.state)) {
187 dev_warn(&device->dev,
188 "Cannot transition to power state %s for parent in %s\n",
189 acpi_power_state_string(state),
190 acpi_power_state_string(device->parent->power.state));
197 * In accordance with ACPI 6, _PSx is executed before manipulating power
198 * resources, unless the target state is D0, in which case _PS0 is
199 * supposed to be executed after turning the power resources on.
201 if (state > ACPI_STATE_D0) {
203 * According to ACPI 6, devices cannot go from lower-power
204 * (deeper) states to higher-power (shallower) states.
206 if (state < device->power.state) {
207 dev_warn(&device->dev, "Cannot transition from %s to %s\n",
208 acpi_power_state_string(device->power.state),
209 acpi_power_state_string(state));
213 result = acpi_dev_pm_explicit_set(device, state);
217 if (device->power.flags.power_resources)
218 result = acpi_power_transition(device, target_state);
220 if (device->power.flags.power_resources) {
221 result = acpi_power_transition(device, ACPI_STATE_D0);
225 result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
230 dev_warn(&device->dev, "Failed to change power state to %s\n",
231 acpi_power_state_string(state));
233 device->power.state = target_state;
234 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
235 "Device [%s] transitioned to %s\n",
237 acpi_power_state_string(state)));
242 EXPORT_SYMBOL(acpi_device_set_power);
244 int acpi_bus_set_power(acpi_handle handle, int state)
246 struct acpi_device *device;
249 result = acpi_bus_get_device(handle, &device);
253 return acpi_device_set_power(device, state);
255 EXPORT_SYMBOL(acpi_bus_set_power);
257 int acpi_bus_init_power(struct acpi_device *device)
265 device->power.state = ACPI_STATE_UNKNOWN;
266 if (!acpi_device_is_present(device)) {
267 device->flags.initialized = false;
271 result = acpi_device_get_power(device, &state);
275 if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {
276 /* Reference count the power resources. */
277 result = acpi_power_on_resources(device, state);
281 if (state == ACPI_STATE_D0) {
283 * If _PSC is not present and the state inferred from
284 * power resources appears to be D0, it still may be
285 * necessary to execute _PS0 at this point, because
286 * another device using the same power resources may
287 * have been put into D0 previously and that's why we
290 result = acpi_dev_pm_explicit_set(device, state);
294 } else if (state == ACPI_STATE_UNKNOWN) {
296 * No power resources and missing _PSC? Cross fingers and make
297 * it D0 in hope that this is what the BIOS put the device into.
298 * [We tried to force D0 here by executing _PS0, but that broke
299 * Toshiba P870-303 in a nasty way.]
301 state = ACPI_STATE_D0;
303 device->power.state = state;
308 * acpi_device_fix_up_power - Force device with missing _PSC into D0.
309 * @device: Device object whose power state is to be fixed up.
311 * Devices without power resources and _PSC, but having _PS0 and _PS3 defined,
312 * are assumed to be put into D0 by the BIOS. However, in some cases that may
313 * not be the case and this function should be used then.
315 int acpi_device_fix_up_power(struct acpi_device *device)
319 if (!device->power.flags.power_resources
320 && !device->power.flags.explicit_get
321 && device->power.state == ACPI_STATE_D0)
322 ret = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
326 EXPORT_SYMBOL_GPL(acpi_device_fix_up_power);
328 int acpi_device_update_power(struct acpi_device *device, int *state_p)
333 if (device->power.state == ACPI_STATE_UNKNOWN) {
334 result = acpi_bus_init_power(device);
335 if (!result && state_p)
336 *state_p = device->power.state;
341 result = acpi_device_get_power(device, &state);
345 if (state == ACPI_STATE_UNKNOWN) {
346 state = ACPI_STATE_D0;
347 result = acpi_device_set_power(device, state);
351 if (device->power.flags.power_resources) {
353 * We don't need to really switch the state, bu we need
354 * to update the power resources' reference counters.
356 result = acpi_power_transition(device, state);
360 device->power.state = state;
367 EXPORT_SYMBOL_GPL(acpi_device_update_power);
369 int acpi_bus_update_power(acpi_handle handle, int *state_p)
371 struct acpi_device *device;
374 result = acpi_bus_get_device(handle, &device);
375 return result ? result : acpi_device_update_power(device, state_p);
377 EXPORT_SYMBOL_GPL(acpi_bus_update_power);
379 bool acpi_bus_power_manageable(acpi_handle handle)
381 struct acpi_device *device;
384 result = acpi_bus_get_device(handle, &device);
385 return result ? false : device->flags.power_manageable;
387 EXPORT_SYMBOL(acpi_bus_power_manageable);
390 static DEFINE_MUTEX(acpi_pm_notifier_lock);
391 static DEFINE_MUTEX(acpi_pm_notifier_install_lock);
393 void acpi_pm_wakeup_event(struct device *dev)
395 pm_wakeup_dev_event(dev, 0, acpi_s2idle_wakeup());
397 EXPORT_SYMBOL_GPL(acpi_pm_wakeup_event);
399 static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used)
401 struct acpi_device *adev;
403 if (val != ACPI_NOTIFY_DEVICE_WAKE)
406 acpi_handle_debug(handle, "Wake notify\n");
408 adev = acpi_bus_get_acpi_device(handle);
412 mutex_lock(&acpi_pm_notifier_lock);
414 if (adev->wakeup.flags.notifier_present) {
415 pm_wakeup_ws_event(adev->wakeup.ws, 0, acpi_s2idle_wakeup());
416 if (adev->wakeup.context.func) {
417 acpi_handle_debug(handle, "Running %pS for %s\n",
418 adev->wakeup.context.func,
419 dev_name(adev->wakeup.context.dev));
420 adev->wakeup.context.func(&adev->wakeup.context);
424 mutex_unlock(&acpi_pm_notifier_lock);
426 acpi_bus_put_acpi_device(adev);
430 * acpi_add_pm_notifier - Register PM notify handler for given ACPI device.
431 * @adev: ACPI device to add the notify handler for.
432 * @dev: Device to generate a wakeup event for while handling the notification.
433 * @func: Work function to execute when handling the notification.
435 * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of
436 * PM wakeup events. For example, wakeup events may be generated for bridges
437 * if one of the devices below the bridge is signaling wakeup, even if the
438 * bridge itself doesn't have a wakeup GPE associated with it.
440 acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev,
441 void (*func)(struct acpi_device_wakeup_context *context))
443 acpi_status status = AE_ALREADY_EXISTS;
446 return AE_BAD_PARAMETER;
448 mutex_lock(&acpi_pm_notifier_install_lock);
450 if (adev->wakeup.flags.notifier_present)
453 status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY,
454 acpi_pm_notify_handler, NULL);
455 if (ACPI_FAILURE(status))
458 mutex_lock(&acpi_pm_notifier_lock);
459 adev->wakeup.ws = wakeup_source_register(dev_name(&adev->dev));
460 adev->wakeup.context.dev = dev;
461 adev->wakeup.context.func = func;
462 adev->wakeup.flags.notifier_present = true;
463 mutex_unlock(&acpi_pm_notifier_lock);
466 mutex_unlock(&acpi_pm_notifier_install_lock);
471 * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
472 * @adev: ACPI device to remove the notifier from.
474 acpi_status acpi_remove_pm_notifier(struct acpi_device *adev)
476 acpi_status status = AE_BAD_PARAMETER;
478 mutex_lock(&acpi_pm_notifier_install_lock);
480 if (!adev->wakeup.flags.notifier_present)
483 status = acpi_remove_notify_handler(adev->handle,
485 acpi_pm_notify_handler);
486 if (ACPI_FAILURE(status))
489 mutex_lock(&acpi_pm_notifier_lock);
490 adev->wakeup.context.func = NULL;
491 adev->wakeup.context.dev = NULL;
492 wakeup_source_unregister(adev->wakeup.ws);
493 adev->wakeup.flags.notifier_present = false;
494 mutex_unlock(&acpi_pm_notifier_lock);
497 mutex_unlock(&acpi_pm_notifier_install_lock);
501 bool acpi_bus_can_wakeup(acpi_handle handle)
503 struct acpi_device *device;
506 result = acpi_bus_get_device(handle, &device);
507 return result ? false : device->wakeup.flags.valid;
509 EXPORT_SYMBOL(acpi_bus_can_wakeup);
511 bool acpi_pm_device_can_wakeup(struct device *dev)
513 struct acpi_device *adev = ACPI_COMPANION(dev);
515 return adev ? acpi_device_can_wakeup(adev) : false;
519 * acpi_dev_pm_get_state - Get preferred power state of ACPI device.
520 * @dev: Device whose preferred target power state to return.
521 * @adev: ACPI device node corresponding to @dev.
522 * @target_state: System state to match the resultant device state.
523 * @d_min_p: Location to store the highest power state available to the device.
524 * @d_max_p: Location to store the lowest power state available to the device.
526 * Find the lowest power (highest number) and highest power (lowest number) ACPI
527 * device power states that the device can be in while the system is in the
528 * state represented by @target_state. Store the integer numbers representing
529 * those stats in the memory locations pointed to by @d_max_p and @d_min_p,
532 * Callers must ensure that @dev and @adev are valid pointers and that @adev
533 * actually corresponds to @dev before using this function.
535 * Returns 0 on success or -ENODATA when one of the ACPI methods fails or
536 * returns a value that doesn't make sense. The memory locations pointed to by
537 * @d_max_p and @d_min_p are only modified on success.
539 static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev,
540 u32 target_state, int *d_min_p, int *d_max_p)
542 char method[] = { '_', 'S', '0' + target_state, 'D', '\0' };
543 acpi_handle handle = adev->handle;
544 unsigned long long ret;
547 bool has_sxd = false;
551 * If the system state is S0, the lowest power state the device can be
552 * in is D3cold, unless the device has _S0W and is supposed to signal
553 * wakeup, in which case the return value of _S0W has to be used as the
554 * lowest power state available to the device.
556 d_min = ACPI_STATE_D0;
557 d_max = ACPI_STATE_D3_COLD;
560 * If present, _SxD methods return the minimum D-state (highest power
561 * state) we can use for the corresponding S-states. Otherwise, the
562 * minimum D-state is D0 (ACPI 3.x).
564 if (target_state > ACPI_STATE_S0) {
566 * We rely on acpi_evaluate_integer() not clobbering the integer
567 * provided if AE_NOT_FOUND is returned.
570 status = acpi_evaluate_integer(handle, method, NULL, &ret);
571 if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND)
572 || ret > ACPI_STATE_D3_COLD)
576 * We need to handle legacy systems where D3hot and D3cold are
577 * the same and 3 is returned in both cases, so fall back to
578 * D3cold if D3hot is not a valid state.
580 if (!adev->power.states[ret].flags.valid) {
581 if (ret == ACPI_STATE_D3_HOT)
582 ret = ACPI_STATE_D3_COLD;
591 wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
592 && adev->wakeup.sleep_state >= target_state;
594 wakeup = adev->wakeup.flags.valid;
598 * If _PRW says we can wake up the system from the target sleep state,
599 * the D-state returned by _SxD is sufficient for that (we assume a
600 * wakeup-aware driver if wake is set). Still, if _SxW exists
601 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
602 * can wake the system. _S0W may be valid, too.
606 status = acpi_evaluate_integer(handle, method, NULL, &ret);
607 if (status == AE_NOT_FOUND) {
608 /* No _SxW. In this case, the ACPI spec says that we
609 * must not go into any power state deeper than the
610 * value returned from _SxD.
612 if (has_sxd && target_state > ACPI_STATE_S0)
614 } else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) {
615 /* Fall back to D3cold if ret is not a valid state. */
616 if (!adev->power.states[ret].flags.valid)
617 ret = ACPI_STATE_D3_COLD;
619 d_max = ret > d_min ? ret : d_min;
635 * acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
636 * @dev: Device whose preferred target power state to return.
637 * @d_min_p: Location to store the upper limit of the allowed states range.
638 * @d_max_in: Deepest low-power state to take into consideration.
639 * Return value: Preferred power state of the device on success, -ENODEV
640 * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is
641 * incorrect, or -ENODATA on ACPI method failure.
643 * The caller must ensure that @dev is valid before using this function.
645 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
647 struct acpi_device *adev;
648 int ret, d_min, d_max;
650 if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD)
653 if (d_max_in > ACPI_STATE_D2) {
654 enum pm_qos_flags_status stat;
656 stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
657 if (stat == PM_QOS_FLAGS_ALL)
658 d_max_in = ACPI_STATE_D2;
661 adev = ACPI_COMPANION(dev);
663 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
667 ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(),
672 if (d_max_in < d_min)
675 if (d_max > d_max_in) {
676 for (d_max = d_max_in; d_max > d_min; d_max--) {
677 if (adev->power.states[d_max].flags.valid)
687 EXPORT_SYMBOL(acpi_pm_device_sleep_state);
690 * acpi_pm_notify_work_func - ACPI devices wakeup notification work function.
691 * @context: Device wakeup context.
693 static void acpi_pm_notify_work_func(struct acpi_device_wakeup_context *context)
695 struct device *dev = context->dev;
698 pm_wakeup_event(dev, 0);
699 pm_request_resume(dev);
703 static DEFINE_MUTEX(acpi_wakeup_lock);
705 static int __acpi_device_wakeup_enable(struct acpi_device *adev,
706 u32 target_state, int max_count)
708 struct acpi_device_wakeup *wakeup = &adev->wakeup;
712 mutex_lock(&acpi_wakeup_lock);
714 if (wakeup->enable_count >= max_count)
717 if (wakeup->enable_count > 0)
720 error = acpi_enable_wakeup_device_power(adev, target_state);
724 status = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
725 if (ACPI_FAILURE(status)) {
726 acpi_disable_wakeup_device_power(adev);
731 acpi_handle_debug(adev->handle, "GPE%2X enabled for wakeup\n",
732 (unsigned int)wakeup->gpe_number);
735 wakeup->enable_count++;
738 mutex_unlock(&acpi_wakeup_lock);
743 * acpi_device_wakeup_enable - Enable wakeup functionality for device.
744 * @adev: ACPI device to enable wakeup functionality for.
745 * @target_state: State the system is transitioning into.
747 * Enable the GPE associated with @adev so that it can generate wakeup signals
748 * for the device in response to external (remote) events and enable wakeup
751 * Callers must ensure that @adev is a valid ACPI device node before executing
754 static int acpi_device_wakeup_enable(struct acpi_device *adev, u32 target_state)
756 return __acpi_device_wakeup_enable(adev, target_state, 1);
760 * acpi_device_wakeup_disable - Disable wakeup functionality for device.
761 * @adev: ACPI device to disable wakeup functionality for.
763 * Disable the GPE associated with @adev and disable wakeup power for it.
765 * Callers must ensure that @adev is a valid ACPI device node before executing
768 static void acpi_device_wakeup_disable(struct acpi_device *adev)
770 struct acpi_device_wakeup *wakeup = &adev->wakeup;
772 mutex_lock(&acpi_wakeup_lock);
774 if (!wakeup->enable_count)
777 acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
778 acpi_disable_wakeup_device_power(adev);
780 wakeup->enable_count--;
783 mutex_unlock(&acpi_wakeup_lock);
786 static int __acpi_pm_set_device_wakeup(struct device *dev, bool enable,
789 struct acpi_device *adev;
792 adev = ACPI_COMPANION(dev);
794 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
798 if (!acpi_device_can_wakeup(adev))
802 acpi_device_wakeup_disable(adev);
803 dev_dbg(dev, "Wakeup disabled by ACPI\n");
807 error = __acpi_device_wakeup_enable(adev, acpi_target_system_state(),
810 dev_dbg(dev, "Wakeup enabled by ACPI\n");
816 * acpi_pm_set_device_wakeup - Enable/disable remote wakeup for given device.
817 * @dev: Device to enable/disable to generate wakeup events.
818 * @enable: Whether to enable or disable the wakeup functionality.
820 int acpi_pm_set_device_wakeup(struct device *dev, bool enable)
822 return __acpi_pm_set_device_wakeup(dev, enable, 1);
824 EXPORT_SYMBOL_GPL(acpi_pm_set_device_wakeup);
827 * acpi_pm_set_bridge_wakeup - Enable/disable remote wakeup for given bridge.
828 * @dev: Bridge device to enable/disable to generate wakeup events.
829 * @enable: Whether to enable or disable the wakeup functionality.
831 int acpi_pm_set_bridge_wakeup(struct device *dev, bool enable)
833 return __acpi_pm_set_device_wakeup(dev, enable, INT_MAX);
835 EXPORT_SYMBOL_GPL(acpi_pm_set_bridge_wakeup);
838 * acpi_dev_pm_low_power - Put ACPI device into a low-power state.
839 * @dev: Device to put into a low-power state.
840 * @adev: ACPI device node corresponding to @dev.
841 * @system_state: System state to choose the device state for.
843 static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev,
848 if (!acpi_device_power_manageable(adev))
851 ret = acpi_dev_pm_get_state(dev, adev, system_state, NULL, &state);
852 return ret ? ret : acpi_device_set_power(adev, state);
856 * acpi_dev_pm_full_power - Put ACPI device into the full-power state.
857 * @adev: ACPI device node to put into the full-power state.
859 static int acpi_dev_pm_full_power(struct acpi_device *adev)
861 return acpi_device_power_manageable(adev) ?
862 acpi_device_set_power(adev, ACPI_STATE_D0) : 0;
866 * acpi_dev_suspend - Put device into a low-power state using ACPI.
867 * @dev: Device to put into a low-power state.
868 * @wakeup: Whether or not to enable wakeup for the device.
870 * Put the given device into a low-power state using the standard ACPI
871 * mechanism. Set up remote wakeup if desired, choose the state to put the
872 * device into (this checks if remote wakeup is expected to work too), and set
873 * the power state of the device.
875 int acpi_dev_suspend(struct device *dev, bool wakeup)
877 struct acpi_device *adev = ACPI_COMPANION(dev);
878 u32 target_state = acpi_target_system_state();
884 if (wakeup && acpi_device_can_wakeup(adev)) {
885 error = acpi_device_wakeup_enable(adev, target_state);
892 error = acpi_dev_pm_low_power(dev, adev, target_state);
894 acpi_device_wakeup_disable(adev);
898 EXPORT_SYMBOL_GPL(acpi_dev_suspend);
901 * acpi_dev_resume - Put device into the full-power state using ACPI.
902 * @dev: Device to put into the full-power state.
904 * Put the given device into the full-power state using the standard ACPI
905 * mechanism. Set the power state of the device to ACPI D0 and disable wakeup.
907 int acpi_dev_resume(struct device *dev)
909 struct acpi_device *adev = ACPI_COMPANION(dev);
915 error = acpi_dev_pm_full_power(adev);
916 acpi_device_wakeup_disable(adev);
919 EXPORT_SYMBOL_GPL(acpi_dev_resume);
922 * acpi_subsys_runtime_suspend - Suspend device using ACPI.
923 * @dev: Device to suspend.
925 * Carry out the generic runtime suspend procedure for @dev and use ACPI to put
926 * it into a runtime low-power state.
928 int acpi_subsys_runtime_suspend(struct device *dev)
930 int ret = pm_generic_runtime_suspend(dev);
931 return ret ? ret : acpi_dev_suspend(dev, true);
933 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);
936 * acpi_subsys_runtime_resume - Resume device using ACPI.
937 * @dev: Device to Resume.
939 * Use ACPI to put the given device into the full-power state and carry out the
940 * generic runtime resume procedure for it.
942 int acpi_subsys_runtime_resume(struct device *dev)
944 int ret = acpi_dev_resume(dev);
945 return ret ? ret : pm_generic_runtime_resume(dev);
947 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
949 #ifdef CONFIG_PM_SLEEP
950 static bool acpi_dev_needs_resume(struct device *dev, struct acpi_device *adev)
952 u32 sys_target = acpi_target_system_state();
955 if (!pm_runtime_suspended(dev) || !adev ||
956 device_may_wakeup(dev) != !!adev->wakeup.prepare_count)
959 if (sys_target == ACPI_STATE_S0)
962 if (adev->power.flags.dsw_present)
965 ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state);
969 return state != adev->power.state;
973 * acpi_subsys_prepare - Prepare device for system transition to a sleep state.
974 * @dev: Device to prepare.
976 int acpi_subsys_prepare(struct device *dev)
978 struct acpi_device *adev = ACPI_COMPANION(dev);
980 if (dev->driver && dev->driver->pm && dev->driver->pm->prepare) {
981 int ret = dev->driver->pm->prepare(dev);
986 if (!ret && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))
990 return !acpi_dev_needs_resume(dev, adev);
992 EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
995 * acpi_subsys_complete - Finalize device's resume during system resume.
996 * @dev: Device to handle.
998 void acpi_subsys_complete(struct device *dev)
1000 pm_generic_complete(dev);
1002 * If the device had been runtime-suspended before the system went into
1003 * the sleep state it is going out of and it has never been resumed till
1004 * now, resume it in case the firmware powered it up.
1006 if (pm_runtime_suspended(dev) && pm_resume_via_firmware())
1007 pm_request_resume(dev);
1009 EXPORT_SYMBOL_GPL(acpi_subsys_complete);
1012 * acpi_subsys_suspend - Run the device driver's suspend callback.
1013 * @dev: Device to handle.
1015 * Follow PCI and resume devices from runtime suspend before running their
1016 * system suspend callbacks, unless the driver can cope with runtime-suspended
1017 * devices during system suspend and there are no ACPI-specific reasons for
1020 int acpi_subsys_suspend(struct device *dev)
1022 if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
1023 acpi_dev_needs_resume(dev, ACPI_COMPANION(dev)))
1024 pm_runtime_resume(dev);
1026 return pm_generic_suspend(dev);
1028 EXPORT_SYMBOL_GPL(acpi_subsys_suspend);
1031 * acpi_subsys_suspend_late - Suspend device using ACPI.
1032 * @dev: Device to suspend.
1034 * Carry out the generic late suspend procedure for @dev and use ACPI to put
1035 * it into a low-power state during system transition into a sleep state.
1037 int acpi_subsys_suspend_late(struct device *dev)
1041 if (dev_pm_smart_suspend_and_suspended(dev))
1044 ret = pm_generic_suspend_late(dev);
1045 return ret ? ret : acpi_dev_suspend(dev, device_may_wakeup(dev));
1047 EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
1050 * acpi_subsys_suspend_noirq - Run the device driver's "noirq" suspend callback.
1051 * @dev: Device to suspend.
1053 int acpi_subsys_suspend_noirq(struct device *dev)
1057 if (dev_pm_smart_suspend_and_suspended(dev)) {
1058 dev->power.may_skip_resume = true;
1062 ret = pm_generic_suspend_noirq(dev);
1067 * If the target system sleep state is suspend-to-idle, it is sufficient
1068 * to check whether or not the device's wakeup settings are good for
1069 * runtime PM. Otherwise, the pm_resume_via_firmware() check will cause
1070 * acpi_subsys_complete() to take care of fixing up the device's state
1071 * anyway, if need be.
1073 dev->power.may_skip_resume = device_may_wakeup(dev) ||
1074 !device_can_wakeup(dev);
1078 EXPORT_SYMBOL_GPL(acpi_subsys_suspend_noirq);
1081 * acpi_subsys_resume_noirq - Run the device driver's "noirq" resume callback.
1082 * @dev: Device to handle.
1084 int acpi_subsys_resume_noirq(struct device *dev)
1086 if (dev_pm_may_skip_resume(dev))
1090 * Devices with DPM_FLAG_SMART_SUSPEND may be left in runtime suspend
1091 * during system suspend, so update their runtime PM status to "active"
1092 * as they will be put into D0 going forward.
1094 if (dev_pm_smart_suspend_and_suspended(dev))
1095 pm_runtime_set_active(dev);
1097 return pm_generic_resume_noirq(dev);
1099 EXPORT_SYMBOL_GPL(acpi_subsys_resume_noirq);
1102 * acpi_subsys_resume_early - Resume device using ACPI.
1103 * @dev: Device to Resume.
1105 * Use ACPI to put the given device into the full-power state and carry out the
1106 * generic early resume procedure for it during system transition into the
1109 int acpi_subsys_resume_early(struct device *dev)
1111 int ret = acpi_dev_resume(dev);
1112 return ret ? ret : pm_generic_resume_early(dev);
1114 EXPORT_SYMBOL_GPL(acpi_subsys_resume_early);
1117 * acpi_subsys_freeze - Run the device driver's freeze callback.
1118 * @dev: Device to handle.
1120 int acpi_subsys_freeze(struct device *dev)
1123 * This used to be done in acpi_subsys_prepare() for all devices and
1124 * some drivers may depend on it, so do it here. Ideally, however,
1125 * runtime-suspended devices should not be touched during freeze/thaw
1128 if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND))
1129 pm_runtime_resume(dev);
1131 return pm_generic_freeze(dev);
1133 EXPORT_SYMBOL_GPL(acpi_subsys_freeze);
1136 * acpi_subsys_freeze_late - Run the device driver's "late" freeze callback.
1137 * @dev: Device to handle.
1139 int acpi_subsys_freeze_late(struct device *dev)
1142 if (dev_pm_smart_suspend_and_suspended(dev))
1145 return pm_generic_freeze_late(dev);
1147 EXPORT_SYMBOL_GPL(acpi_subsys_freeze_late);
1150 * acpi_subsys_freeze_noirq - Run the device driver's "noirq" freeze callback.
1151 * @dev: Device to handle.
1153 int acpi_subsys_freeze_noirq(struct device *dev)
1156 if (dev_pm_smart_suspend_and_suspended(dev))
1159 return pm_generic_freeze_noirq(dev);
1161 EXPORT_SYMBOL_GPL(acpi_subsys_freeze_noirq);
1164 * acpi_subsys_thaw_noirq - Run the device driver's "noirq" thaw callback.
1165 * @dev: Device to handle.
1167 int acpi_subsys_thaw_noirq(struct device *dev)
1170 * If the device is in runtime suspend, the "thaw" code may not work
1171 * correctly with it, so skip the driver callback and make the PM core
1172 * skip all of the subsequent "thaw" callbacks for the device.
1174 if (dev_pm_smart_suspend_and_suspended(dev)) {
1175 dev_pm_skip_next_resume_phases(dev);
1179 return pm_generic_thaw_noirq(dev);
1181 EXPORT_SYMBOL_GPL(acpi_subsys_thaw_noirq);
1182 #endif /* CONFIG_PM_SLEEP */
1184 static struct dev_pm_domain acpi_general_pm_domain = {
1186 .runtime_suspend = acpi_subsys_runtime_suspend,
1187 .runtime_resume = acpi_subsys_runtime_resume,
1188 #ifdef CONFIG_PM_SLEEP
1189 .prepare = acpi_subsys_prepare,
1190 .complete = acpi_subsys_complete,
1191 .suspend = acpi_subsys_suspend,
1192 .suspend_late = acpi_subsys_suspend_late,
1193 .suspend_noirq = acpi_subsys_suspend_noirq,
1194 .resume_noirq = acpi_subsys_resume_noirq,
1195 .resume_early = acpi_subsys_resume_early,
1196 .freeze = acpi_subsys_freeze,
1197 .freeze_late = acpi_subsys_freeze_late,
1198 .freeze_noirq = acpi_subsys_freeze_noirq,
1199 .thaw_noirq = acpi_subsys_thaw_noirq,
1200 .poweroff = acpi_subsys_suspend,
1201 .poweroff_late = acpi_subsys_suspend_late,
1202 .poweroff_noirq = acpi_subsys_suspend_noirq,
1203 .restore_noirq = acpi_subsys_resume_noirq,
1204 .restore_early = acpi_subsys_resume_early,
1210 * acpi_dev_pm_detach - Remove ACPI power management from the device.
1211 * @dev: Device to take care of.
1212 * @power_off: Whether or not to try to remove power from the device.
1214 * Remove the device from the general ACPI PM domain and remove its wakeup
1215 * notifier. If @power_off is set, additionally remove power from the device if
1218 * Callers must ensure proper synchronization of this function with power
1219 * management callbacks.
1221 static void acpi_dev_pm_detach(struct device *dev, bool power_off)
1223 struct acpi_device *adev = ACPI_COMPANION(dev);
1225 if (adev && dev->pm_domain == &acpi_general_pm_domain) {
1226 dev_pm_domain_set(dev, NULL);
1227 acpi_remove_pm_notifier(adev);
1230 * If the device's PM QoS resume latency limit or flags
1231 * have been exposed to user space, they have to be
1232 * hidden at this point, so that they don't affect the
1233 * choice of the low-power state to put the device into.
1235 dev_pm_qos_hide_latency_limit(dev);
1236 dev_pm_qos_hide_flags(dev);
1237 acpi_device_wakeup_disable(adev);
1238 acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
1244 * acpi_dev_pm_attach - Prepare device for ACPI power management.
1245 * @dev: Device to prepare.
1246 * @power_on: Whether or not to power on the device.
1248 * If @dev has a valid ACPI handle that has a valid struct acpi_device object
1249 * attached to it, install a wakeup notification handler for the device and
1250 * add it to the general ACPI PM domain. If @power_on is set, the device will
1251 * be put into the ACPI D0 state before the function returns.
1253 * This assumes that the @dev's bus type uses generic power management callbacks
1254 * (or doesn't use any power management callbacks at all).
1256 * Callers must ensure proper synchronization of this function with power
1257 * management callbacks.
1259 int acpi_dev_pm_attach(struct device *dev, bool power_on)
1261 struct acpi_device *adev = ACPI_COMPANION(dev);
1267 * Only attach the power domain to the first device if the
1268 * companion is shared by multiple. This is to prevent doing power
1271 if (!acpi_device_is_first_physical_node(adev, dev))
1274 acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func);
1275 dev_pm_domain_set(dev, &acpi_general_pm_domain);
1277 acpi_dev_pm_full_power(adev);
1278 acpi_device_wakeup_disable(adev);
1281 dev->pm_domain->detach = acpi_dev_pm_detach;
1284 EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
1285 #endif /* CONFIG_PM */