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 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25 #include <linux/acpi.h>
26 #include <linux/export.h>
27 #include <linux/mutex.h>
28 #include <linux/pm_qos.h>
29 #include <linux/pm_runtime.h>
33 #define _COMPONENT ACPI_POWER_COMPONENT
34 ACPI_MODULE_NAME("device_pm");
37 * acpi_power_state_string - String representation of ACPI device power state.
38 * @state: ACPI device power state to return the string representation of.
40 const char *acpi_power_state_string(int state)
49 case ACPI_STATE_D3_HOT:
51 case ACPI_STATE_D3_COLD:
59 * acpi_device_get_power - Get power state of an ACPI device.
60 * @device: Device to get the power state of.
61 * @state: Place to store the power state of the device.
63 * This function does not update the device's power.state field, but it may
64 * update its parent's power.state field (when the parent's power state is
65 * unknown and the device's power state turns out to be D0).
67 int acpi_device_get_power(struct acpi_device *device, int *state)
69 int result = ACPI_STATE_UNKNOWN;
71 if (!device || !state)
74 if (!device->flags.power_manageable) {
75 /* TBD: Non-recursive algorithm for walking up hierarchy. */
76 *state = device->parent ?
77 device->parent->power.state : ACPI_STATE_D0;
82 * Get the device's power state from power resources settings and _PSC,
85 if (device->power.flags.power_resources) {
86 int error = acpi_power_get_inferred_state(device, &result);
90 if (device->power.flags.explicit_get) {
91 acpi_handle handle = device->handle;
92 unsigned long long psc;
95 status = acpi_evaluate_integer(handle, "_PSC", NULL, &psc);
96 if (ACPI_FAILURE(status))
100 * The power resources settings may indicate a power state
101 * shallower than the actual power state of the device, because
102 * the same power resources may be referenced by other devices.
104 * For systems predating ACPI 4.0 we assume that D3hot is the
105 * deepest state that can be supported.
107 if (psc > result && psc < ACPI_STATE_D3_COLD)
109 else if (result == ACPI_STATE_UNKNOWN)
110 result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_HOT : psc;
114 * If we were unsure about the device parent's power state up to this
115 * point, the fact that the device is in D0 implies that the parent has
116 * to be in D0 too, except if ignore_parent is set.
118 if (!device->power.flags.ignore_parent && device->parent
119 && device->parent->power.state == ACPI_STATE_UNKNOWN
120 && result == ACPI_STATE_D0)
121 device->parent->power.state = ACPI_STATE_D0;
126 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n",
127 device->pnp.bus_id, acpi_power_state_string(*state)));
132 static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state)
134 if (adev->power.states[state].flags.explicit_set) {
135 char method[5] = { '_', 'P', 'S', '0' + state, '\0' };
138 status = acpi_evaluate_object(adev->handle, method, NULL, NULL);
139 if (ACPI_FAILURE(status))
146 * acpi_device_set_power - Set power state of an ACPI device.
147 * @device: Device to set the power state of.
148 * @state: New power state to set.
150 * Callers must ensure that the device is power manageable before using this
153 int acpi_device_set_power(struct acpi_device *device, int state)
155 int target_state = state;
158 if (!device || !device->flags.power_manageable
159 || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
162 /* Make sure this is a valid target state */
164 if (state == device->power.state) {
165 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already in %s\n",
167 acpi_power_state_string(state)));
171 if (state == ACPI_STATE_D3_COLD) {
173 * For transitions to D3cold we need to execute _PS3 and then
174 * possibly drop references to the power resources in use.
176 state = ACPI_STATE_D3_HOT;
177 /* If _PR3 is not available, use D3hot as the target state. */
178 if (!device->power.states[ACPI_STATE_D3_COLD].flags.valid)
179 target_state = state;
180 } else if (!device->power.states[state].flags.valid) {
181 dev_warn(&device->dev, "Power state %s not supported\n",
182 acpi_power_state_string(state));
186 if (!device->power.flags.ignore_parent &&
187 device->parent && (state < device->parent->power.state)) {
188 dev_warn(&device->dev,
189 "Cannot transition to power state %s for parent in %s\n",
190 acpi_power_state_string(state),
191 acpi_power_state_string(device->parent->power.state));
198 * In accordance with ACPI 6, _PSx is executed before manipulating power
199 * resources, unless the target state is D0, in which case _PS0 is
200 * supposed to be executed after turning the power resources on.
202 if (state > ACPI_STATE_D0) {
204 * According to ACPI 6, devices cannot go from lower-power
205 * (deeper) states to higher-power (shallower) states.
207 if (state < device->power.state) {
208 dev_warn(&device->dev, "Cannot transition from %s to %s\n",
209 acpi_power_state_string(device->power.state),
210 acpi_power_state_string(state));
214 result = acpi_dev_pm_explicit_set(device, state);
218 if (device->power.flags.power_resources)
219 result = acpi_power_transition(device, target_state);
221 if (device->power.flags.power_resources) {
222 result = acpi_power_transition(device, ACPI_STATE_D0);
226 result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
231 dev_warn(&device->dev, "Failed to change power state to %s\n",
232 acpi_power_state_string(state));
234 device->power.state = target_state;
235 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
236 "Device [%s] transitioned to %s\n",
238 acpi_power_state_string(state)));
243 EXPORT_SYMBOL(acpi_device_set_power);
245 int acpi_bus_set_power(acpi_handle handle, int state)
247 struct acpi_device *device;
250 result = acpi_bus_get_device(handle, &device);
254 return acpi_device_set_power(device, state);
256 EXPORT_SYMBOL(acpi_bus_set_power);
258 int acpi_bus_init_power(struct acpi_device *device)
266 device->power.state = ACPI_STATE_UNKNOWN;
267 if (!acpi_device_is_present(device))
270 result = acpi_device_get_power(device, &state);
274 if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {
275 /* Reference count the power resources. */
276 result = acpi_power_on_resources(device, state);
280 if (state == ACPI_STATE_D0) {
282 * If _PSC is not present and the state inferred from
283 * power resources appears to be D0, it still may be
284 * necessary to execute _PS0 at this point, because
285 * another device using the same power resources may
286 * have been put into D0 previously and that's why we
289 result = acpi_dev_pm_explicit_set(device, state);
293 } else if (state == ACPI_STATE_UNKNOWN) {
295 * No power resources and missing _PSC? Cross fingers and make
296 * it D0 in hope that this is what the BIOS put the device into.
297 * [We tried to force D0 here by executing _PS0, but that broke
298 * Toshiba P870-303 in a nasty way.]
300 state = ACPI_STATE_D0;
302 device->power.state = state;
307 * acpi_device_fix_up_power - Force device with missing _PSC into D0.
308 * @device: Device object whose power state is to be fixed up.
310 * Devices without power resources and _PSC, but having _PS0 and _PS3 defined,
311 * are assumed to be put into D0 by the BIOS. However, in some cases that may
312 * not be the case and this function should be used then.
314 int acpi_device_fix_up_power(struct acpi_device *device)
318 if (!device->power.flags.power_resources
319 && !device->power.flags.explicit_get
320 && device->power.state == ACPI_STATE_D0)
321 ret = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
326 int acpi_device_update_power(struct acpi_device *device, int *state_p)
331 if (device->power.state == ACPI_STATE_UNKNOWN) {
332 result = acpi_bus_init_power(device);
333 if (!result && state_p)
334 *state_p = device->power.state;
339 result = acpi_device_get_power(device, &state);
343 if (state == ACPI_STATE_UNKNOWN) {
344 state = ACPI_STATE_D0;
345 result = acpi_device_set_power(device, state);
349 if (device->power.flags.power_resources) {
351 * We don't need to really switch the state, bu we need
352 * to update the power resources' reference counters.
354 result = acpi_power_transition(device, state);
358 device->power.state = state;
365 EXPORT_SYMBOL_GPL(acpi_device_update_power);
367 int acpi_bus_update_power(acpi_handle handle, int *state_p)
369 struct acpi_device *device;
372 result = acpi_bus_get_device(handle, &device);
373 return result ? result : acpi_device_update_power(device, state_p);
375 EXPORT_SYMBOL_GPL(acpi_bus_update_power);
377 bool acpi_bus_power_manageable(acpi_handle handle)
379 struct acpi_device *device;
382 result = acpi_bus_get_device(handle, &device);
383 return result ? false : device->flags.power_manageable;
385 EXPORT_SYMBOL(acpi_bus_power_manageable);
388 static DEFINE_MUTEX(acpi_pm_notifier_lock);
390 static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used)
392 struct acpi_device *adev;
394 if (val != ACPI_NOTIFY_DEVICE_WAKE)
397 adev = acpi_bus_get_acpi_device(handle);
401 mutex_lock(&acpi_pm_notifier_lock);
403 if (adev->wakeup.flags.notifier_present) {
404 __pm_wakeup_event(adev->wakeup.ws, 0);
405 if (adev->wakeup.context.work.func)
406 queue_pm_work(&adev->wakeup.context.work);
409 mutex_unlock(&acpi_pm_notifier_lock);
411 acpi_bus_put_acpi_device(adev);
415 * acpi_add_pm_notifier - Register PM notify handler for given ACPI device.
416 * @adev: ACPI device to add the notify handler for.
417 * @dev: Device to generate a wakeup event for while handling the notification.
418 * @work_func: Work function to execute when handling the notification.
420 * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of
421 * PM wakeup events. For example, wakeup events may be generated for bridges
422 * if one of the devices below the bridge is signaling wakeup, even if the
423 * bridge itself doesn't have a wakeup GPE associated with it.
425 acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev,
426 void (*work_func)(struct work_struct *work))
428 acpi_status status = AE_ALREADY_EXISTS;
430 if (!dev && !work_func)
431 return AE_BAD_PARAMETER;
433 mutex_lock(&acpi_pm_notifier_lock);
435 if (adev->wakeup.flags.notifier_present)
438 adev->wakeup.ws = wakeup_source_register(dev_name(&adev->dev));
439 adev->wakeup.context.dev = dev;
441 INIT_WORK(&adev->wakeup.context.work, work_func);
443 status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY,
444 acpi_pm_notify_handler, NULL);
445 if (ACPI_FAILURE(status))
448 adev->wakeup.flags.notifier_present = true;
451 mutex_unlock(&acpi_pm_notifier_lock);
456 * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
457 * @adev: ACPI device to remove the notifier from.
459 acpi_status acpi_remove_pm_notifier(struct acpi_device *adev)
461 acpi_status status = AE_BAD_PARAMETER;
463 mutex_lock(&acpi_pm_notifier_lock);
465 if (!adev->wakeup.flags.notifier_present)
468 status = acpi_remove_notify_handler(adev->handle,
470 acpi_pm_notify_handler);
471 if (ACPI_FAILURE(status))
474 if (adev->wakeup.context.work.func) {
475 cancel_work_sync(&adev->wakeup.context.work);
476 adev->wakeup.context.work.func = NULL;
478 adev->wakeup.context.dev = NULL;
479 wakeup_source_unregister(adev->wakeup.ws);
481 adev->wakeup.flags.notifier_present = false;
484 mutex_unlock(&acpi_pm_notifier_lock);
488 bool acpi_bus_can_wakeup(acpi_handle handle)
490 struct acpi_device *device;
493 result = acpi_bus_get_device(handle, &device);
494 return result ? false : device->wakeup.flags.valid;
496 EXPORT_SYMBOL(acpi_bus_can_wakeup);
499 * acpi_dev_pm_get_state - Get preferred power state of ACPI device.
500 * @dev: Device whose preferred target power state to return.
501 * @adev: ACPI device node corresponding to @dev.
502 * @target_state: System state to match the resultant device state.
503 * @d_min_p: Location to store the highest power state available to the device.
504 * @d_max_p: Location to store the lowest power state available to the device.
506 * Find the lowest power (highest number) and highest power (lowest number) ACPI
507 * device power states that the device can be in while the system is in the
508 * state represented by @target_state. Store the integer numbers representing
509 * those stats in the memory locations pointed to by @d_max_p and @d_min_p,
512 * Callers must ensure that @dev and @adev are valid pointers and that @adev
513 * actually corresponds to @dev before using this function.
515 * Returns 0 on success or -ENODATA when one of the ACPI methods fails or
516 * returns a value that doesn't make sense. The memory locations pointed to by
517 * @d_max_p and @d_min_p are only modified on success.
519 static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev,
520 u32 target_state, int *d_min_p, int *d_max_p)
522 char method[] = { '_', 'S', '0' + target_state, 'D', '\0' };
523 acpi_handle handle = adev->handle;
524 unsigned long long ret;
530 * If the system state is S0, the lowest power state the device can be
531 * in is D3cold, unless the device has _S0W and is supposed to signal
532 * wakeup, in which case the return value of _S0W has to be used as the
533 * lowest power state available to the device.
535 d_min = ACPI_STATE_D0;
536 d_max = ACPI_STATE_D3_COLD;
539 * If present, _SxD methods return the minimum D-state (highest power
540 * state) we can use for the corresponding S-states. Otherwise, the
541 * minimum D-state is D0 (ACPI 3.x).
543 if (target_state > ACPI_STATE_S0) {
545 * We rely on acpi_evaluate_integer() not clobbering the integer
546 * provided if AE_NOT_FOUND is returned.
549 status = acpi_evaluate_integer(handle, method, NULL, &ret);
550 if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND)
551 || ret > ACPI_STATE_D3_COLD)
555 * We need to handle legacy systems where D3hot and D3cold are
556 * the same and 3 is returned in both cases, so fall back to
557 * D3cold if D3hot is not a valid state.
559 if (!adev->power.states[ret].flags.valid) {
560 if (ret == ACPI_STATE_D3_HOT)
561 ret = ACPI_STATE_D3_COLD;
566 wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
567 && adev->wakeup.sleep_state >= target_state;
568 } else if (dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) !=
570 wakeup = adev->wakeup.flags.valid;
574 * If _PRW says we can wake up the system from the target sleep state,
575 * the D-state returned by _SxD is sufficient for that (we assume a
576 * wakeup-aware driver if wake is set). Still, if _SxW exists
577 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
578 * can wake the system. _S0W may be valid, too.
582 status = acpi_evaluate_integer(handle, method, NULL, &ret);
583 if (status == AE_NOT_FOUND) {
584 if (target_state > ACPI_STATE_S0)
586 } else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) {
587 /* Fall back to D3cold if ret is not a valid state. */
588 if (!adev->power.states[ret].flags.valid)
589 ret = ACPI_STATE_D3_COLD;
591 d_max = ret > d_min ? ret : d_min;
607 * acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
608 * @dev: Device whose preferred target power state to return.
609 * @d_min_p: Location to store the upper limit of the allowed states range.
610 * @d_max_in: Deepest low-power state to take into consideration.
611 * Return value: Preferred power state of the device on success, -ENODEV
612 * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is
613 * incorrect, or -ENODATA on ACPI method failure.
615 * The caller must ensure that @dev is valid before using this function.
617 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
619 struct acpi_device *adev;
620 int ret, d_min, d_max;
622 if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD)
625 if (d_max_in > ACPI_STATE_D2) {
626 enum pm_qos_flags_status stat;
628 stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
629 if (stat == PM_QOS_FLAGS_ALL)
630 d_max_in = ACPI_STATE_D2;
633 adev = ACPI_COMPANION(dev);
635 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
639 ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(),
644 if (d_max_in < d_min)
647 if (d_max > d_max_in) {
648 for (d_max = d_max_in; d_max > d_min; d_max--) {
649 if (adev->power.states[d_max].flags.valid)
659 EXPORT_SYMBOL(acpi_pm_device_sleep_state);
662 * acpi_pm_notify_work_func - ACPI devices wakeup notification work function.
663 * @work: Work item to handle.
665 static void acpi_pm_notify_work_func(struct work_struct *work)
669 dev = container_of(work, struct acpi_device_wakeup_context, work)->dev;
671 pm_wakeup_event(dev, 0);
672 pm_runtime_resume(dev);
677 * acpi_device_wakeup - Enable/disable wakeup functionality for device.
678 * @adev: ACPI device to enable/disable wakeup functionality for.
679 * @target_state: State the system is transitioning into.
680 * @enable: Whether to enable or disable the wakeup functionality.
682 * Enable/disable the GPE associated with @adev so that it can generate
683 * wakeup signals for the device in response to external (remote) events and
684 * enable/disable device wakeup power.
686 * Callers must ensure that @adev is a valid ACPI device node before executing
689 static int acpi_device_wakeup(struct acpi_device *adev, u32 target_state,
692 struct acpi_device_wakeup *wakeup = &adev->wakeup;
698 error = acpi_enable_wakeup_device_power(adev, target_state);
702 if (adev->wakeup.flags.enabled)
705 res = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
706 if (ACPI_SUCCESS(res)) {
707 adev->wakeup.flags.enabled = 1;
709 acpi_disable_wakeup_device_power(adev);
713 if (adev->wakeup.flags.enabled) {
714 acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
715 adev->wakeup.flags.enabled = 0;
717 acpi_disable_wakeup_device_power(adev);
723 * acpi_pm_device_run_wake - Enable/disable remote wakeup for given device.
724 * @dev: Device to enable/disable the platform to wake up.
725 * @enable: Whether to enable or disable the wakeup functionality.
727 int acpi_pm_device_run_wake(struct device *phys_dev, bool enable)
729 struct acpi_device *adev;
731 if (!device_run_wake(phys_dev))
734 adev = ACPI_COMPANION(phys_dev);
736 dev_dbg(phys_dev, "ACPI companion missing in %s!\n", __func__);
740 return acpi_device_wakeup(adev, ACPI_STATE_S0, enable);
742 EXPORT_SYMBOL(acpi_pm_device_run_wake);
744 #ifdef CONFIG_PM_SLEEP
746 * acpi_pm_device_sleep_wake - Enable or disable device to wake up the system.
747 * @dev: Device to enable/desible to wake up the system from sleep states.
748 * @enable: Whether to enable or disable @dev to wake up the system.
750 int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
752 struct acpi_device *adev;
755 if (!device_can_wakeup(dev))
758 adev = ACPI_COMPANION(dev);
760 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
764 error = acpi_device_wakeup(adev, acpi_target_system_state(), enable);
766 dev_info(dev, "System wakeup %s by ACPI\n",
767 enable ? "enabled" : "disabled");
771 #endif /* CONFIG_PM_SLEEP */
774 * acpi_dev_pm_low_power - Put ACPI device into a low-power state.
775 * @dev: Device to put into a low-power state.
776 * @adev: ACPI device node corresponding to @dev.
777 * @system_state: System state to choose the device state for.
779 static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev,
784 if (!acpi_device_power_manageable(adev))
787 ret = acpi_dev_pm_get_state(dev, adev, system_state, NULL, &state);
788 return ret ? ret : acpi_device_set_power(adev, state);
792 * acpi_dev_pm_full_power - Put ACPI device into the full-power state.
793 * @adev: ACPI device node to put into the full-power state.
795 static int acpi_dev_pm_full_power(struct acpi_device *adev)
797 return acpi_device_power_manageable(adev) ?
798 acpi_device_set_power(adev, ACPI_STATE_D0) : 0;
802 * acpi_dev_runtime_suspend - Put device into a low-power state using ACPI.
803 * @dev: Device to put into a low-power state.
805 * Put the given device into a runtime low-power state using the standard ACPI
806 * mechanism. Set up remote wakeup if desired, choose the state to put the
807 * device into (this checks if remote wakeup is expected to work too), and set
808 * the power state of the device.
810 int acpi_dev_runtime_suspend(struct device *dev)
812 struct acpi_device *adev = ACPI_COMPANION(dev);
819 remote_wakeup = dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) >
821 error = acpi_device_wakeup(adev, ACPI_STATE_S0, remote_wakeup);
822 if (remote_wakeup && error)
825 error = acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
827 acpi_device_wakeup(adev, ACPI_STATE_S0, false);
831 EXPORT_SYMBOL_GPL(acpi_dev_runtime_suspend);
834 * acpi_dev_runtime_resume - Put device into the full-power state using ACPI.
835 * @dev: Device to put into the full-power state.
837 * Put the given device into the full-power state using the standard ACPI
838 * mechanism at run time. Set the power state of the device to ACPI D0 and
839 * disable remote wakeup.
841 int acpi_dev_runtime_resume(struct device *dev)
843 struct acpi_device *adev = ACPI_COMPANION(dev);
849 error = acpi_dev_pm_full_power(adev);
850 acpi_device_wakeup(adev, ACPI_STATE_S0, false);
853 EXPORT_SYMBOL_GPL(acpi_dev_runtime_resume);
856 * acpi_subsys_runtime_suspend - Suspend device using ACPI.
857 * @dev: Device to suspend.
859 * Carry out the generic runtime suspend procedure for @dev and use ACPI to put
860 * it into a runtime low-power state.
862 int acpi_subsys_runtime_suspend(struct device *dev)
864 int ret = pm_generic_runtime_suspend(dev);
865 return ret ? ret : acpi_dev_runtime_suspend(dev);
867 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);
870 * acpi_subsys_runtime_resume - Resume device using ACPI.
871 * @dev: Device to Resume.
873 * Use ACPI to put the given device into the full-power state and carry out the
874 * generic runtime resume procedure for it.
876 int acpi_subsys_runtime_resume(struct device *dev)
878 int ret = acpi_dev_runtime_resume(dev);
879 return ret ? ret : pm_generic_runtime_resume(dev);
881 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
883 #ifdef CONFIG_PM_SLEEP
885 * acpi_dev_suspend_late - Put device into a low-power state using ACPI.
886 * @dev: Device to put into a low-power state.
888 * Put the given device into a low-power state during system transition to a
889 * sleep state using the standard ACPI mechanism. Set up system wakeup if
890 * desired, choose the state to put the device into (this checks if system
891 * wakeup is expected to work too), and set the power state of the device.
893 int acpi_dev_suspend_late(struct device *dev)
895 struct acpi_device *adev = ACPI_COMPANION(dev);
903 target_state = acpi_target_system_state();
904 wakeup = device_may_wakeup(dev) && acpi_device_can_wakeup(adev);
905 error = acpi_device_wakeup(adev, target_state, wakeup);
909 error = acpi_dev_pm_low_power(dev, adev, target_state);
911 acpi_device_wakeup(adev, ACPI_STATE_UNKNOWN, false);
915 EXPORT_SYMBOL_GPL(acpi_dev_suspend_late);
918 * acpi_dev_resume_early - Put device into the full-power state using ACPI.
919 * @dev: Device to put into the full-power state.
921 * Put the given device into the full-power state using the standard ACPI
922 * mechanism during system transition to the working state. Set the power
923 * state of the device to ACPI D0 and disable remote wakeup.
925 int acpi_dev_resume_early(struct device *dev)
927 struct acpi_device *adev = ACPI_COMPANION(dev);
933 error = acpi_dev_pm_full_power(adev);
934 acpi_device_wakeup(adev, ACPI_STATE_UNKNOWN, false);
937 EXPORT_SYMBOL_GPL(acpi_dev_resume_early);
940 * acpi_subsys_prepare - Prepare device for system transition to a sleep state.
941 * @dev: Device to prepare.
943 int acpi_subsys_prepare(struct device *dev)
945 struct acpi_device *adev = ACPI_COMPANION(dev);
949 ret = pm_generic_prepare(dev);
953 if (!adev || !pm_runtime_suspended(dev)
954 || device_may_wakeup(dev) != !!adev->wakeup.prepare_count)
957 sys_target = acpi_target_system_state();
958 if (sys_target == ACPI_STATE_S0)
961 if (adev->power.flags.dsw_present)
964 ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state);
965 return !ret && state == adev->power.state;
967 EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
970 * acpi_subsys_complete - Finalize device's resume during system resume.
971 * @dev: Device to handle.
973 void acpi_subsys_complete(struct device *dev)
975 pm_generic_complete(dev);
977 * If the device had been runtime-suspended before the system went into
978 * the sleep state it is going out of and it has never been resumed till
979 * now, resume it in case the firmware powered it up.
981 if (dev->power.direct_complete)
982 pm_request_resume(dev);
984 EXPORT_SYMBOL_GPL(acpi_subsys_complete);
987 * acpi_subsys_suspend - Run the device driver's suspend callback.
988 * @dev: Device to handle.
990 * Follow PCI and resume devices suspended at run time before running their
991 * system suspend callbacks.
993 int acpi_subsys_suspend(struct device *dev)
995 pm_runtime_resume(dev);
996 return pm_generic_suspend(dev);
998 EXPORT_SYMBOL_GPL(acpi_subsys_suspend);
1001 * acpi_subsys_suspend_late - Suspend device using ACPI.
1002 * @dev: Device to suspend.
1004 * Carry out the generic late suspend procedure for @dev and use ACPI to put
1005 * it into a low-power state during system transition into a sleep state.
1007 int acpi_subsys_suspend_late(struct device *dev)
1009 int ret = pm_generic_suspend_late(dev);
1010 return ret ? ret : acpi_dev_suspend_late(dev);
1012 EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
1015 * acpi_subsys_resume_early - Resume device using ACPI.
1016 * @dev: Device to Resume.
1018 * Use ACPI to put the given device into the full-power state and carry out the
1019 * generic early resume procedure for it during system transition into the
1022 int acpi_subsys_resume_early(struct device *dev)
1024 int ret = acpi_dev_resume_early(dev);
1025 return ret ? ret : pm_generic_resume_early(dev);
1027 EXPORT_SYMBOL_GPL(acpi_subsys_resume_early);
1030 * acpi_subsys_freeze - Run the device driver's freeze callback.
1031 * @dev: Device to handle.
1033 int acpi_subsys_freeze(struct device *dev)
1036 * This used to be done in acpi_subsys_prepare() for all devices and
1037 * some drivers may depend on it, so do it here. Ideally, however,
1038 * runtime-suspended devices should not be touched during freeze/thaw
1041 pm_runtime_resume(dev);
1042 return pm_generic_freeze(dev);
1044 EXPORT_SYMBOL_GPL(acpi_subsys_freeze);
1046 #endif /* CONFIG_PM_SLEEP */
1048 static struct dev_pm_domain acpi_general_pm_domain = {
1050 .runtime_suspend = acpi_subsys_runtime_suspend,
1051 .runtime_resume = acpi_subsys_runtime_resume,
1052 #ifdef CONFIG_PM_SLEEP
1053 .prepare = acpi_subsys_prepare,
1054 .complete = acpi_subsys_complete,
1055 .suspend = acpi_subsys_suspend,
1056 .suspend_late = acpi_subsys_suspend_late,
1057 .resume_early = acpi_subsys_resume_early,
1058 .freeze = acpi_subsys_freeze,
1059 .poweroff = acpi_subsys_suspend,
1060 .poweroff_late = acpi_subsys_suspend_late,
1061 .restore_early = acpi_subsys_resume_early,
1067 * acpi_dev_pm_detach - Remove ACPI power management from the device.
1068 * @dev: Device to take care of.
1069 * @power_off: Whether or not to try to remove power from the device.
1071 * Remove the device from the general ACPI PM domain and remove its wakeup
1072 * notifier. If @power_off is set, additionally remove power from the device if
1075 * Callers must ensure proper synchronization of this function with power
1076 * management callbacks.
1078 static void acpi_dev_pm_detach(struct device *dev, bool power_off)
1080 struct acpi_device *adev = ACPI_COMPANION(dev);
1082 if (adev && dev->pm_domain == &acpi_general_pm_domain) {
1083 dev->pm_domain = NULL;
1084 acpi_remove_pm_notifier(adev);
1087 * If the device's PM QoS resume latency limit or flags
1088 * have been exposed to user space, they have to be
1089 * hidden at this point, so that they don't affect the
1090 * choice of the low-power state to put the device into.
1092 dev_pm_qos_hide_latency_limit(dev);
1093 dev_pm_qos_hide_flags(dev);
1094 acpi_device_wakeup(adev, ACPI_STATE_S0, false);
1095 acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
1101 * acpi_dev_pm_attach - Prepare device for ACPI power management.
1102 * @dev: Device to prepare.
1103 * @power_on: Whether or not to power on the device.
1105 * If @dev has a valid ACPI handle that has a valid struct acpi_device object
1106 * attached to it, install a wakeup notification handler for the device and
1107 * add it to the general ACPI PM domain. If @power_on is set, the device will
1108 * be put into the ACPI D0 state before the function returns.
1110 * This assumes that the @dev's bus type uses generic power management callbacks
1111 * (or doesn't use any power management callbacks at all).
1113 * Callers must ensure proper synchronization of this function with power
1114 * management callbacks.
1116 int acpi_dev_pm_attach(struct device *dev, bool power_on)
1118 struct acpi_device *adev = ACPI_COMPANION(dev);
1126 acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func);
1127 dev->pm_domain = &acpi_general_pm_domain;
1129 acpi_dev_pm_full_power(adev);
1130 acpi_device_wakeup(adev, ACPI_STATE_S0, false);
1133 dev->pm_domain->detach = acpi_dev_pm_detach;
1136 EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
1137 #endif /* CONFIG_PM */