device_pm.c 31.6 KB
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/*
 * drivers/acpi/device_pm.c - ACPI device power management routines.
 *
 * Copyright (C) 2012, Intel Corp.
 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as published
 *  by the Free Software Foundation.
 *
 *  This program is distributed in the hope that it will be useful, but
 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  General Public License for more details.
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */

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#include <linux/acpi.h>
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#include <linux/export.h>
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#include <linux/mutex.h>
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#include <linux/pm_qos.h>
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#include <linux/pm_domain.h>
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#include <linux/pm_runtime.h>
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#include "internal.h"

#define _COMPONENT	ACPI_POWER_COMPONENT
ACPI_MODULE_NAME("device_pm");
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/**
 * acpi_power_state_string - String representation of ACPI device power state.
 * @state: ACPI device power state to return the string representation of.
 */
const char *acpi_power_state_string(int state)
{
	switch (state) {
	case ACPI_STATE_D0:
		return "D0";
	case ACPI_STATE_D1:
		return "D1";
	case ACPI_STATE_D2:
		return "D2";
	case ACPI_STATE_D3_HOT:
		return "D3hot";
	case ACPI_STATE_D3_COLD:
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		return "D3cold";
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	default:
		return "(unknown)";
	}
}

/**
 * acpi_device_get_power - Get power state of an ACPI device.
 * @device: Device to get the power state of.
 * @state: Place to store the power state of the device.
 *
 * This function does not update the device's power.state field, but it may
 * update its parent's power.state field (when the parent's power state is
 * unknown and the device's power state turns out to be D0).
 */
int acpi_device_get_power(struct acpi_device *device, int *state)
{
	int result = ACPI_STATE_UNKNOWN;

	if (!device || !state)
		return -EINVAL;

	if (!device->flags.power_manageable) {
		/* TBD: Non-recursive algorithm for walking up hierarchy. */
		*state = device->parent ?
			device->parent->power.state : ACPI_STATE_D0;
		goto out;
	}

	/*
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	 * Get the device's power state from power resources settings and _PSC,
	 * if available.
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	 */
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	if (device->power.flags.power_resources) {
		int error = acpi_power_get_inferred_state(device, &result);
		if (error)
			return error;
	}
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	if (device->power.flags.explicit_get) {
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		acpi_handle handle = device->handle;
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		unsigned long long psc;
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		acpi_status status;

		status = acpi_evaluate_integer(handle, "_PSC", NULL, &psc);
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		if (ACPI_FAILURE(status))
			return -ENODEV;

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		/*
		 * The power resources settings may indicate a power state
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		 * shallower than the actual power state of the device, because
		 * the same power resources may be referenced by other devices.
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		 *
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		 * For systems predating ACPI 4.0 we assume that D3hot is the
		 * deepest state that can be supported.
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		 */
		if (psc > result && psc < ACPI_STATE_D3_COLD)
			result = psc;
		else if (result == ACPI_STATE_UNKNOWN)
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			result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_HOT : psc;
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	}

	/*
	 * If we were unsure about the device parent's power state up to this
	 * point, the fact that the device is in D0 implies that the parent has
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	 * to be in D0 too, except if ignore_parent is set.
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	 */
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	if (!device->power.flags.ignore_parent && device->parent
	    && device->parent->power.state == ACPI_STATE_UNKNOWN
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	    && result == ACPI_STATE_D0)
		device->parent->power.state = ACPI_STATE_D0;

	*state = result;

 out:
	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n",
			  device->pnp.bus_id, acpi_power_state_string(*state)));

	return 0;
}

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static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state)
{
	if (adev->power.states[state].flags.explicit_set) {
		char method[5] = { '_', 'P', 'S', '0' + state, '\0' };
		acpi_status status;

		status = acpi_evaluate_object(adev->handle, method, NULL, NULL);
		if (ACPI_FAILURE(status))
			return -ENODEV;
	}
	return 0;
}

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/**
 * acpi_device_set_power - Set power state of an ACPI device.
 * @device: Device to set the power state of.
 * @state: New power state to set.
 *
 * Callers must ensure that the device is power manageable before using this
 * function.
 */
int acpi_device_set_power(struct acpi_device *device, int state)
{
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	int target_state = state;
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	int result = 0;

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	if (!device || !device->flags.power_manageable
	    || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
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		return -EINVAL;

	/* Make sure this is a valid target state */

	if (state == device->power.state) {
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		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already in %s\n",
				  device->pnp.bus_id,
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				  acpi_power_state_string(state)));
		return 0;
	}

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	if (state == ACPI_STATE_D3_COLD) {
		/*
		 * For transitions to D3cold we need to execute _PS3 and then
		 * possibly drop references to the power resources in use.
		 */
		state = ACPI_STATE_D3_HOT;
		/* If _PR3 is not available, use D3hot as the target state. */
		if (!device->power.states[ACPI_STATE_D3_COLD].flags.valid)
			target_state = state;
	} else if (!device->power.states[state].flags.valid) {
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		dev_warn(&device->dev, "Power state %s not supported\n",
			 acpi_power_state_string(state));
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		return -ENODEV;
	}
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	if (!device->power.flags.ignore_parent &&
	    device->parent && (state < device->parent->power.state)) {
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		dev_warn(&device->dev,
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			 "Cannot transition to power state %s for parent in %s\n",
			 acpi_power_state_string(state),
			 acpi_power_state_string(device->parent->power.state));
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		return -ENODEV;
	}

	/*
	 * Transition Power
	 * ----------------
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	 * In accordance with ACPI 6, _PSx is executed before manipulating power
	 * resources, unless the target state is D0, in which case _PS0 is
	 * supposed to be executed after turning the power resources on.
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	 */
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	if (state > ACPI_STATE_D0) {
		/*
		 * According to ACPI 6, devices cannot go from lower-power
		 * (deeper) states to higher-power (shallower) states.
		 */
		if (state < device->power.state) {
			dev_warn(&device->dev, "Cannot transition from %s to %s\n",
				 acpi_power_state_string(device->power.state),
				 acpi_power_state_string(state));
			return -ENODEV;
		}

		result = acpi_dev_pm_explicit_set(device, state);
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		if (result)
			goto end;
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		if (device->power.flags.power_resources)
			result = acpi_power_transition(device, target_state);
	} else {
		if (device->power.flags.power_resources) {
			result = acpi_power_transition(device, ACPI_STATE_D0);
			if (result)
				goto end;
		}
		result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
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	}
225

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 end:
	if (result) {
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		dev_warn(&device->dev, "Failed to change power state to %s\n",
			 acpi_power_state_string(state));
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	} else {
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		device->power.state = target_state;
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		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Device [%s] transitioned to %s\n",
				  device->pnp.bus_id,
				  acpi_power_state_string(state)));
	}

	return result;
}
EXPORT_SYMBOL(acpi_device_set_power);

int acpi_bus_set_power(acpi_handle handle, int state)
{
	struct acpi_device *device;
	int result;

	result = acpi_bus_get_device(handle, &device);
	if (result)
		return result;

	return acpi_device_set_power(device, state);
}
EXPORT_SYMBOL(acpi_bus_set_power);

int acpi_bus_init_power(struct acpi_device *device)
{
	int state;
	int result;

	if (!device)
		return -EINVAL;

	device->power.state = ACPI_STATE_UNKNOWN;
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	if (!acpi_device_is_present(device))
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		return -ENXIO;
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	result = acpi_device_get_power(device, &state);
	if (result)
		return result;

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	if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {
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		/* Reference count the power resources. */
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		result = acpi_power_on_resources(device, state);
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		if (result)
			return result;
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		if (state == ACPI_STATE_D0) {
			/*
			 * If _PSC is not present and the state inferred from
			 * power resources appears to be D0, it still may be
			 * necessary to execute _PS0 at this point, because
			 * another device using the same power resources may
			 * have been put into D0 previously and that's why we
			 * see D0 here.
			 */
			result = acpi_dev_pm_explicit_set(device, state);
			if (result)
				return result;
		}
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	} else if (state == ACPI_STATE_UNKNOWN) {
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		/*
		 * No power resources and missing _PSC?  Cross fingers and make
		 * it D0 in hope that this is what the BIOS put the device into.
		 * [We tried to force D0 here by executing _PS0, but that broke
		 * Toshiba P870-303 in a nasty way.]
		 */
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		state = ACPI_STATE_D0;
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	}
	device->power.state = state;
	return 0;
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}

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/**
 * acpi_device_fix_up_power - Force device with missing _PSC into D0.
 * @device: Device object whose power state is to be fixed up.
 *
 * Devices without power resources and _PSC, but having _PS0 and _PS3 defined,
 * are assumed to be put into D0 by the BIOS.  However, in some cases that may
 * not be the case and this function should be used then.
 */
int acpi_device_fix_up_power(struct acpi_device *device)
{
	int ret = 0;

	if (!device->power.flags.power_resources
	    && !device->power.flags.explicit_get
	    && device->power.state == ACPI_STATE_D0)
		ret = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);

	return ret;
}

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int acpi_device_update_power(struct acpi_device *device, int *state_p)
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{
	int state;
	int result;

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	if (device->power.state == ACPI_STATE_UNKNOWN) {
		result = acpi_bus_init_power(device);
		if (!result && state_p)
			*state_p = device->power.state;

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		return result;
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	}
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	result = acpi_device_get_power(device, &state);
	if (result)
		return result;

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	if (state == ACPI_STATE_UNKNOWN) {
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		state = ACPI_STATE_D0;
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		result = acpi_device_set_power(device, state);
		if (result)
			return result;
	} else {
		if (device->power.flags.power_resources) {
			/*
			 * We don't need to really switch the state, bu we need
			 * to update the power resources' reference counters.
			 */
			result = acpi_power_transition(device, state);
			if (result)
				return result;
		}
		device->power.state = state;
	}
	if (state_p)
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		*state_p = state;

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	return 0;
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}
362
EXPORT_SYMBOL_GPL(acpi_device_update_power);
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int acpi_bus_update_power(acpi_handle handle, int *state_p)
{
	struct acpi_device *device;
	int result;

	result = acpi_bus_get_device(handle, &device);
	return result ? result : acpi_device_update_power(device, state_p);
}
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EXPORT_SYMBOL_GPL(acpi_bus_update_power);

bool acpi_bus_power_manageable(acpi_handle handle)
{
	struct acpi_device *device;
	int result;

	result = acpi_bus_get_device(handle, &device);
	return result ? false : device->flags.power_manageable;
}
EXPORT_SYMBOL(acpi_bus_power_manageable);

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#ifdef CONFIG_PM
static DEFINE_MUTEX(acpi_pm_notifier_lock);

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static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used)
{
	struct acpi_device *adev;

	if (val != ACPI_NOTIFY_DEVICE_WAKE)
		return;

	adev = acpi_bus_get_acpi_device(handle);
	if (!adev)
		return;

	mutex_lock(&acpi_pm_notifier_lock);

	if (adev->wakeup.flags.notifier_present) {
		__pm_wakeup_event(adev->wakeup.ws, 0);
		if (adev->wakeup.context.work.func)
			queue_pm_work(&adev->wakeup.context.work);
	}

	mutex_unlock(&acpi_pm_notifier_lock);

	acpi_bus_put_acpi_device(adev);
}

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/**
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 * acpi_add_pm_notifier - Register PM notify handler for given ACPI device.
 * @adev: ACPI device to add the notify handler for.
 * @dev: Device to generate a wakeup event for while handling the notification.
 * @work_func: Work function to execute when handling the notification.
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 *
 * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of
 * PM wakeup events.  For example, wakeup events may be generated for bridges
 * if one of the devices below the bridge is signaling wakeup, even if the
 * bridge itself doesn't have a wakeup GPE associated with it.
 */
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acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev,
				 void (*work_func)(struct work_struct *work))
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{
	acpi_status status = AE_ALREADY_EXISTS;

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	if (!dev && !work_func)
		return AE_BAD_PARAMETER;

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	mutex_lock(&acpi_pm_notifier_lock);

	if (adev->wakeup.flags.notifier_present)
		goto out;

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	adev->wakeup.ws = wakeup_source_register(dev_name(&adev->dev));
	adev->wakeup.context.dev = dev;
	if (work_func)
		INIT_WORK(&adev->wakeup.context.work, work_func);

	status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY,
					     acpi_pm_notify_handler, NULL);
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	if (ACPI_FAILURE(status))
		goto out;

	adev->wakeup.flags.notifier_present = true;

 out:
	mutex_unlock(&acpi_pm_notifier_lock);
	return status;
}

/**
 * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
 * @adev: ACPI device to remove the notifier from.
 */
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acpi_status acpi_remove_pm_notifier(struct acpi_device *adev)
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{
	acpi_status status = AE_BAD_PARAMETER;

	mutex_lock(&acpi_pm_notifier_lock);

	if (!adev->wakeup.flags.notifier_present)
		goto out;

	status = acpi_remove_notify_handler(adev->handle,
					    ACPI_SYSTEM_NOTIFY,
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					    acpi_pm_notify_handler);
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	if (ACPI_FAILURE(status))
		goto out;

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	if (adev->wakeup.context.work.func) {
		cancel_work_sync(&adev->wakeup.context.work);
		adev->wakeup.context.work.func = NULL;
	}
	adev->wakeup.context.dev = NULL;
	wakeup_source_unregister(adev->wakeup.ws);

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	adev->wakeup.flags.notifier_present = false;

 out:
	mutex_unlock(&acpi_pm_notifier_lock);
	return status;
}

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bool acpi_bus_can_wakeup(acpi_handle handle)
{
	struct acpi_device *device;
	int result;

	result = acpi_bus_get_device(handle, &device);
	return result ? false : device->wakeup.flags.valid;
}
EXPORT_SYMBOL(acpi_bus_can_wakeup);

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/**
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 * acpi_dev_pm_get_state - Get preferred power state of ACPI device.
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 * @dev: Device whose preferred target power state to return.
 * @adev: ACPI device node corresponding to @dev.
 * @target_state: System state to match the resultant device state.
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 * @d_min_p: Location to store the highest power state available to the device.
 * @d_max_p: Location to store the lowest power state available to the device.
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 *
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 * Find the lowest power (highest number) and highest power (lowest number) ACPI
 * device power states that the device can be in while the system is in the
 * state represented by @target_state.  Store the integer numbers representing
 * those stats in the memory locations pointed to by @d_max_p and @d_min_p,
 * respectively.
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 *
 * Callers must ensure that @dev and @adev are valid pointers and that @adev
 * actually corresponds to @dev before using this function.
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 *
 * Returns 0 on success or -ENODATA when one of the ACPI methods fails or
 * returns a value that doesn't make sense.  The memory locations pointed to by
 * @d_max_p and @d_min_p are only modified on success.
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 */
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static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev,
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				 u32 target_state, int *d_min_p, int *d_max_p)
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{
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	char method[] = { '_', 'S', '0' + target_state, 'D', '\0' };
	acpi_handle handle = adev->handle;
	unsigned long long ret;
	int d_min, d_max;
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	bool wakeup = false;
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	acpi_status status;
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	/*
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	 * If the system state is S0, the lowest power state the device can be
	 * in is D3cold, unless the device has _S0W and is supposed to signal
	 * wakeup, in which case the return value of _S0W has to be used as the
	 * lowest power state available to the device.
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	 */
	d_min = ACPI_STATE_D0;
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	d_max = ACPI_STATE_D3_COLD;
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	/*
	 * If present, _SxD methods return the minimum D-state (highest power
	 * state) we can use for the corresponding S-states.  Otherwise, the
	 * minimum D-state is D0 (ACPI 3.x).
	 */
	if (target_state > ACPI_STATE_S0) {
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		/*
		 * We rely on acpi_evaluate_integer() not clobbering the integer
		 * provided if AE_NOT_FOUND is returned.
		 */
		ret = d_min;
		status = acpi_evaluate_integer(handle, method, NULL, &ret);
		if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND)
		    || ret > ACPI_STATE_D3_COLD)
			return -ENODATA;

		/*
		 * We need to handle legacy systems where D3hot and D3cold are
		 * the same and 3 is returned in both cases, so fall back to
		 * D3cold if D3hot is not a valid state.
		 */
		if (!adev->power.states[ret].flags.valid) {
			if (ret == ACPI_STATE_D3_HOT)
				ret = ACPI_STATE_D3_COLD;
			else
				return -ENODATA;
		}
		d_min = ret;
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		wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
			&& adev->wakeup.sleep_state >= target_state;
	} else if (dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) !=
			PM_QOS_FLAGS_NONE) {
		wakeup = adev->wakeup.flags.valid;
	}

	/*
	 * If _PRW says we can wake up the system from the target sleep state,
	 * the D-state returned by _SxD is sufficient for that (we assume a
	 * wakeup-aware driver if wake is set).  Still, if _SxW exists
	 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
	 * can wake the system.  _S0W may be valid, too.
	 */
	if (wakeup) {
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		method[3] = 'W';
		status = acpi_evaluate_integer(handle, method, NULL, &ret);
		if (status == AE_NOT_FOUND) {
			if (target_state > ACPI_STATE_S0)
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				d_max = d_min;
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		} else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) {
			/* Fall back to D3cold if ret is not a valid state. */
			if (!adev->power.states[ret].flags.valid)
				ret = ACPI_STATE_D3_COLD;

			d_max = ret > d_min ? ret : d_min;
		} else {
			return -ENODATA;
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		}
	}

	if (d_min_p)
		*d_min_p = d_min;
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	if (d_max_p)
		*d_max_p = d_max;

	return 0;
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}
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/**
 * acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
 * @dev: Device whose preferred target power state to return.
 * @d_min_p: Location to store the upper limit of the allowed states range.
 * @d_max_in: Deepest low-power state to take into consideration.
 * Return value: Preferred power state of the device on success, -ENODEV
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 * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is
 * incorrect, or -ENODATA on ACPI method failure.
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 *
 * The caller must ensure that @dev is valid before using this function.
 */
int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
{
	struct acpi_device *adev;
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	int ret, d_min, d_max;
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	if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD)
		return -EINVAL;

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	if (d_max_in > ACPI_STATE_D2) {
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		enum pm_qos_flags_status stat;

		stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
		if (stat == PM_QOS_FLAGS_ALL)
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			d_max_in = ACPI_STATE_D2;
628
	}
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	adev = ACPI_COMPANION(dev);
	if (!adev) {
		dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
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		return -ENODEV;
	}

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	ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(),
637
				    &d_min, &d_max);
638 639 640
	if (ret)
		return ret;

641
	if (d_max_in < d_min)
642 643 644
		return -EINVAL;

	if (d_max > d_max_in) {
645
		for (d_max = d_max_in; d_max > d_min; d_max--) {
646 647 648 649
			if (adev->power.states[d_max].flags.valid)
				break;
		}
	}
650 651 652 653

	if (d_min_p)
		*d_min_p = d_min;

654
	return d_max;
655 656 657
}
EXPORT_SYMBOL(acpi_pm_device_sleep_state);

658
/**
659 660
 * acpi_pm_notify_work_func - ACPI devices wakeup notification work function.
 * @work: Work item to handle.
661
 */
662
static void acpi_pm_notify_work_func(struct work_struct *work)
663
{
664
	struct device *dev;
665

666 667
	dev = container_of(work, struct acpi_device_wakeup_context, work)->dev;
	if (dev) {
668 669 670 671 672
		pm_wakeup_event(dev, 0);
		pm_runtime_resume(dev);
	}
}

673
/**
674 675 676
 * acpi_device_wakeup - Enable/disable wakeup functionality for device.
 * @adev: ACPI device to enable/disable wakeup functionality for.
 * @target_state: State the system is transitioning into.
677 678
 * @enable: Whether to enable or disable the wakeup functionality.
 *
679 680 681 682 683 684 685
 * Enable/disable the GPE associated with @adev so that it can generate
 * wakeup signals for the device in response to external (remote) events and
 * enable/disable device wakeup power.
 *
 * Callers must ensure that @adev is a valid ACPI device node before executing
 * this function.
 */
686 687
static int acpi_device_wakeup(struct acpi_device *adev, u32 target_state,
			      bool enable)
688 689 690 691 692 693 694
{
	struct acpi_device_wakeup *wakeup = &adev->wakeup;

	if (enable) {
		acpi_status res;
		int error;

695
		error = acpi_enable_wakeup_device_power(adev, target_state);
696 697 698
		if (error)
			return error;

699 700 701
		if (adev->wakeup.flags.enabled)
			return 0;

702
		res = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
703 704 705
		if (ACPI_SUCCESS(res)) {
			adev->wakeup.flags.enabled = 1;
		} else {
706 707 708 709
			acpi_disable_wakeup_device_power(adev);
			return -EIO;
		}
	} else {
710 711 712 713
		if (adev->wakeup.flags.enabled) {
			acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
			adev->wakeup.flags.enabled = 0;
		}
714 715 716 717 718 719 720 721 722
		acpi_disable_wakeup_device_power(adev);
	}
	return 0;
}

/**
 * acpi_pm_device_run_wake - Enable/disable remote wakeup for given device.
 * @dev: Device to enable/disable the platform to wake up.
 * @enable: Whether to enable or disable the wakeup functionality.
723 724 725
 */
int acpi_pm_device_run_wake(struct device *phys_dev, bool enable)
{
726
	struct acpi_device *adev;
727 728 729 730

	if (!device_run_wake(phys_dev))
		return -EINVAL;

731 732 733
	adev = ACPI_COMPANION(phys_dev);
	if (!adev) {
		dev_dbg(phys_dev, "ACPI companion missing in %s!\n", __func__);
734 735 736
		return -ENODEV;
	}

737
	return acpi_device_wakeup(adev, ACPI_STATE_S0, enable);
738 739
}
EXPORT_SYMBOL(acpi_pm_device_run_wake);
740

741
#ifdef CONFIG_PM_SLEEP
742 743 744 745 746 747 748 749 750 751 752 753 754
/**
 * acpi_pm_device_sleep_wake - Enable or disable device to wake up the system.
 * @dev: Device to enable/desible to wake up the system from sleep states.
 * @enable: Whether to enable or disable @dev to wake up the system.
 */
int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
{
	struct acpi_device *adev;
	int error;

	if (!device_can_wakeup(dev))
		return -EINVAL;

755 756 757
	adev = ACPI_COMPANION(dev);
	if (!adev) {
		dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
758 759 760
		return -ENODEV;
	}

761
	error = acpi_device_wakeup(adev, acpi_target_system_state(), enable);
762 763 764 765 766 767
	if (!error)
		dev_info(dev, "System wakeup %s by ACPI\n",
				enable ? "enabled" : "disabled");

	return error;
}
768
#endif /* CONFIG_PM_SLEEP */
769 770 771 772 773 774 775 776 777 778

/**
 * acpi_dev_pm_low_power - Put ACPI device into a low-power state.
 * @dev: Device to put into a low-power state.
 * @adev: ACPI device node corresponding to @dev.
 * @system_state: System state to choose the device state for.
 */
static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev,
				 u32 system_state)
{
779
	int ret, state;
780 781 782 783

	if (!acpi_device_power_manageable(adev))
		return 0;

784 785
	ret = acpi_dev_pm_get_state(dev, adev, system_state, NULL, &state);
	return ret ? ret : acpi_device_set_power(adev, state);
786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808
}

/**
 * acpi_dev_pm_full_power - Put ACPI device into the full-power state.
 * @adev: ACPI device node to put into the full-power state.
 */
static int acpi_dev_pm_full_power(struct acpi_device *adev)
{
	return acpi_device_power_manageable(adev) ?
		acpi_device_set_power(adev, ACPI_STATE_D0) : 0;
}

/**
 * acpi_dev_runtime_suspend - Put device into a low-power state using ACPI.
 * @dev: Device to put into a low-power state.
 *
 * Put the given device into a runtime low-power state using the standard ACPI
 * mechanism.  Set up remote wakeup if desired, choose the state to put the
 * device into (this checks if remote wakeup is expected to work too), and set
 * the power state of the device.
 */
int acpi_dev_runtime_suspend(struct device *dev)
{
809
	struct acpi_device *adev = ACPI_COMPANION(dev);
810 811 812 813 814 815 816 817
	bool remote_wakeup;
	int error;

	if (!adev)
		return 0;

	remote_wakeup = dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) >
				PM_QOS_FLAGS_NONE;
818
	error = acpi_device_wakeup(adev, ACPI_STATE_S0, remote_wakeup);
819 820 821 822 823
	if (remote_wakeup && error)
		return -EAGAIN;

	error = acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
	if (error)
824
		acpi_device_wakeup(adev, ACPI_STATE_S0, false);
825 826 827 828 829 830 831 832 833 834 835 836 837 838 839

	return error;
}
EXPORT_SYMBOL_GPL(acpi_dev_runtime_suspend);

/**
 * acpi_dev_runtime_resume - Put device into the full-power state using ACPI.
 * @dev: Device to put into the full-power state.
 *
 * Put the given device into the full-power state using the standard ACPI
 * mechanism at run time.  Set the power state of the device to ACPI D0 and
 * disable remote wakeup.
 */
int acpi_dev_runtime_resume(struct device *dev)
{
840
	struct acpi_device *adev = ACPI_COMPANION(dev);
841 842 843 844 845 846
	int error;

	if (!adev)
		return 0;

	error = acpi_dev_pm_full_power(adev);
847
	acpi_device_wakeup(adev, ACPI_STATE_S0, false);
848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891
	return error;
}
EXPORT_SYMBOL_GPL(acpi_dev_runtime_resume);

/**
 * acpi_subsys_runtime_suspend - Suspend device using ACPI.
 * @dev: Device to suspend.
 *
 * Carry out the generic runtime suspend procedure for @dev and use ACPI to put
 * it into a runtime low-power state.
 */
int acpi_subsys_runtime_suspend(struct device *dev)
{
	int ret = pm_generic_runtime_suspend(dev);
	return ret ? ret : acpi_dev_runtime_suspend(dev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);

/**
 * acpi_subsys_runtime_resume - Resume device using ACPI.
 * @dev: Device to Resume.
 *
 * Use ACPI to put the given device into the full-power state and carry out the
 * generic runtime resume procedure for it.
 */
int acpi_subsys_runtime_resume(struct device *dev)
{
	int ret = acpi_dev_runtime_resume(dev);
	return ret ? ret : pm_generic_runtime_resume(dev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);

#ifdef CONFIG_PM_SLEEP
/**
 * acpi_dev_suspend_late - Put device into a low-power state using ACPI.
 * @dev: Device to put into a low-power state.
 *
 * Put the given device into a low-power state during system transition to a
 * sleep state using the standard ACPI mechanism.  Set up system wakeup if
 * desired, choose the state to put the device into (this checks if system
 * wakeup is expected to work too), and set the power state of the device.
 */
int acpi_dev_suspend_late(struct device *dev)
{
892
	struct acpi_device *adev = ACPI_COMPANION(dev);
893 894 895 896 897 898 899 900
	u32 target_state;
	bool wakeup;
	int error;

	if (!adev)
		return 0;

	target_state = acpi_target_system_state();
901
	wakeup = device_may_wakeup(dev) && acpi_device_can_wakeup(adev);
902
	error = acpi_device_wakeup(adev, target_state, wakeup);
903 904 905 906 907
	if (wakeup && error)
		return error;

	error = acpi_dev_pm_low_power(dev, adev, target_state);
	if (error)
908
		acpi_device_wakeup(adev, ACPI_STATE_UNKNOWN, false);
909 910 911 912 913 914 915 916 917 918 919 920 921 922 923

	return error;
}
EXPORT_SYMBOL_GPL(acpi_dev_suspend_late);

/**
 * acpi_dev_resume_early - Put device into the full-power state using ACPI.
 * @dev: Device to put into the full-power state.
 *
 * Put the given device into the full-power state using the standard ACPI
 * mechanism during system transition to the working state.  Set the power
 * state of the device to ACPI D0 and disable remote wakeup.
 */
int acpi_dev_resume_early(struct device *dev)
{
924
	struct acpi_device *adev = ACPI_COMPANION(dev);
925 926 927 928 929 930
	int error;

	if (!adev)
		return 0;

	error = acpi_dev_pm_full_power(adev);
931
	acpi_device_wakeup(adev, ACPI_STATE_UNKNOWN, false);
932 933 934 935 936 937 938 939 940 941
	return error;
}
EXPORT_SYMBOL_GPL(acpi_dev_resume_early);

/**
 * acpi_subsys_prepare - Prepare device for system transition to a sleep state.
 * @dev: Device to prepare.
 */
int acpi_subsys_prepare(struct device *dev)
{
942 943 944 945 946 947 948 949 950 951 952 953 954 955 956
	struct acpi_device *adev = ACPI_COMPANION(dev);
	u32 sys_target;
	int ret, state;

	ret = pm_generic_prepare(dev);
	if (ret < 0)
		return ret;

	if (!adev || !pm_runtime_suspended(dev)
	    || device_may_wakeup(dev) != !!adev->wakeup.prepare_count)
		return 0;

	sys_target = acpi_target_system_state();
	if (sys_target == ACPI_STATE_S0)
		return 1;
957

958 959 960 961 962
	if (adev->power.flags.dsw_present)
		return 0;

	ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state);
	return !ret && state == adev->power.state;
963 964 965
}
EXPORT_SYMBOL_GPL(acpi_subsys_prepare);

966 967 968 969 970 971 972 973 974 975 976 977
/**
 * acpi_subsys_suspend - Run the device driver's suspend callback.
 * @dev: Device to handle.
 *
 * Follow PCI and resume devices suspended at run time before running their
 * system suspend callbacks.
 */
int acpi_subsys_suspend(struct device *dev)
{
	pm_runtime_resume(dev);
	return pm_generic_suspend(dev);
}
978
EXPORT_SYMBOL_GPL(acpi_subsys_suspend);
979

980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007
/**
 * acpi_subsys_suspend_late - Suspend device using ACPI.
 * @dev: Device to suspend.
 *
 * Carry out the generic late suspend procedure for @dev and use ACPI to put
 * it into a low-power state during system transition into a sleep state.
 */
int acpi_subsys_suspend_late(struct device *dev)
{
	int ret = pm_generic_suspend_late(dev);
	return ret ? ret : acpi_dev_suspend_late(dev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);

/**
 * acpi_subsys_resume_early - Resume device using ACPI.
 * @dev: Device to Resume.
 *
 * Use ACPI to put the given device into the full-power state and carry out the
 * generic early resume procedure for it during system transition into the
 * working state.
 */
int acpi_subsys_resume_early(struct device *dev)
{
	int ret = acpi_dev_resume_early(dev);
	return ret ? ret : pm_generic_resume_early(dev);
}
EXPORT_SYMBOL_GPL(acpi_subsys_resume_early);
1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023

/**
 * acpi_subsys_freeze - Run the device driver's freeze callback.
 * @dev: Device to handle.
 */
int acpi_subsys_freeze(struct device *dev)
{
	/*
	 * This used to be done in acpi_subsys_prepare() for all devices and
	 * some drivers may depend on it, so do it here.  Ideally, however,
	 * runtime-suspended devices should not be touched during freeze/thaw
	 * transitions.
	 */
	pm_runtime_resume(dev);
	return pm_generic_freeze(dev);
}
1024
EXPORT_SYMBOL_GPL(acpi_subsys_freeze);
1025

1026 1027 1028 1029 1030 1031 1032 1033
#endif /* CONFIG_PM_SLEEP */

static struct dev_pm_domain acpi_general_pm_domain = {
	.ops = {
		.runtime_suspend = acpi_subsys_runtime_suspend,
		.runtime_resume = acpi_subsys_runtime_resume,
#ifdef CONFIG_PM_SLEEP
		.prepare = acpi_subsys_prepare,
1034
		.complete = pm_complete_with_resume_check,
1035
		.suspend = acpi_subsys_suspend,
1036 1037
		.suspend_late = acpi_subsys_suspend_late,
		.resume_early = acpi_subsys_resume_early,
1038 1039
		.freeze = acpi_subsys_freeze,
		.poweroff = acpi_subsys_suspend,
1040 1041 1042 1043 1044 1045
		.poweroff_late = acpi_subsys_suspend_late,
		.restore_early = acpi_subsys_resume_early,
#endif
	},
};

1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062
/**
 * acpi_dev_pm_detach - Remove ACPI power management from the device.
 * @dev: Device to take care of.
 * @power_off: Whether or not to try to remove power from the device.
 *
 * Remove the device from the general ACPI PM domain and remove its wakeup
 * notifier.  If @power_off is set, additionally remove power from the device if
 * possible.
 *
 * Callers must ensure proper synchronization of this function with power
 * management callbacks.
 */
static void acpi_dev_pm_detach(struct device *dev, bool power_off)
{
	struct acpi_device *adev = ACPI_COMPANION(dev);

	if (adev && dev->pm_domain == &acpi_general_pm_domain) {
1063
		dev_pm_domain_set(dev, NULL);
1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079
		acpi_remove_pm_notifier(adev);
		if (power_off) {
			/*
			 * If the device's PM QoS resume latency limit or flags
			 * have been exposed to user space, they have to be
			 * hidden at this point, so that they don't affect the
			 * choice of the low-power state to put the device into.
			 */
			dev_pm_qos_hide_latency_limit(dev);
			dev_pm_qos_hide_flags(dev);
			acpi_device_wakeup(adev, ACPI_STATE_S0, false);
			acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
		}
	}
}

1080 1081 1082
/**
 * acpi_dev_pm_attach - Prepare device for ACPI power management.
 * @dev: Device to prepare.
1083
 * @power_on: Whether or not to power on the device.
1084 1085 1086
 *
 * If @dev has a valid ACPI handle that has a valid struct acpi_device object
 * attached to it, install a wakeup notification handler for the device and
1087 1088
 * add it to the general ACPI PM domain.  If @power_on is set, the device will
 * be put into the ACPI D0 state before the function returns.
1089 1090 1091 1092 1093 1094 1095
 *
 * This assumes that the @dev's bus type uses generic power management callbacks
 * (or doesn't use any power management callbacks at all).
 *
 * Callers must ensure proper synchronization of this function with power
 * management callbacks.
 */
1096
int acpi_dev_pm_attach(struct device *dev, bool power_on)
1097
{
1098
	struct acpi_device *adev = ACPI_COMPANION(dev);
1099 1100 1101 1102 1103 1104 1105

	if (!adev)
		return -ENODEV;

	if (dev->pm_domain)
		return -EEXIST;

1106 1107 1108 1109 1110 1111 1112 1113
	/*
	 * Only attach the power domain to the first device if the
	 * companion is shared by multiple. This is to prevent doing power
	 * management twice.
	 */
	if (!acpi_device_is_first_physical_node(adev, dev))
		return -EBUSY;

1114
	acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func);
1115
	dev_pm_domain_set(dev, &acpi_general_pm_domain);
1116 1117
	if (power_on) {
		acpi_dev_pm_full_power(adev);
1118
		acpi_device_wakeup(adev, ACPI_STATE_S0, false);
1119
	}
1120 1121

	dev->pm_domain->detach = acpi_dev_pm_detach;
1122 1123 1124
	return 0;
}
EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
1125
#endif /* CONFIG_PM */