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// SPDX-License-Identifier: GPL-2.0+
/*
 * I2C multi-instantiate driver, pseudo driver to instantiate multiple
 * i2c-clients from a single fwnode.
 *
 * Copyright 2018 Hans de Goede <hdegoede@redhat.com>
 */

#include <linux/acpi.h>
#include <linux/bits.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/types.h>

#define IRQ_RESOURCE_TYPE	GENMASK(1, 0)
#define IRQ_RESOURCE_NONE	0
#define IRQ_RESOURCE_GPIO	1
#define IRQ_RESOURCE_APIC	2

struct i2c_inst_data {
	const char *type;
	unsigned int flags;
	int irq_idx;
};

struct i2c_multi_inst_data {
	int num_clients;
	struct i2c_client *clients[0];
};

static int i2c_multi_inst_count(struct acpi_resource *ares, void *data)
{
	struct acpi_resource_i2c_serialbus *sb;
	int *count = data;

	if (i2c_acpi_get_i2c_resource(ares, &sb))
		*count = *count + 1;

	return 1;
}

static int i2c_multi_inst_count_resources(struct acpi_device *adev)
{
	LIST_HEAD(r);
	int count = 0;
	int ret;

	ret = acpi_dev_get_resources(adev, &r, i2c_multi_inst_count, &count);
	if (ret < 0)
		return ret;

	acpi_dev_free_resource_list(&r);
	return count;
}

static int i2c_multi_inst_probe(struct platform_device *pdev)
{
	struct i2c_multi_inst_data *multi;
	const struct acpi_device_id *match;
	const struct i2c_inst_data *inst_data;
	struct i2c_board_info board_info = {};
	struct device *dev = &pdev->dev;
	struct acpi_device *adev;
	char name[32];
	int i, ret;

	match = acpi_match_device(dev->driver->acpi_match_table, dev);
	if (!match) {
		dev_err(dev, "Error ACPI match data is missing\n");
		return -ENODEV;
	}
	inst_data = (const struct i2c_inst_data *)match->driver_data;

	adev = ACPI_COMPANION(dev);

	/* Count number of clients to instantiate */
	ret = i2c_multi_inst_count_resources(adev);
	if (ret < 0)
		return ret;

	multi = devm_kmalloc(dev,
			offsetof(struct i2c_multi_inst_data, clients[ret]),
			GFP_KERNEL);
	if (!multi)
		return -ENOMEM;

	multi->num_clients = ret;

	for (i = 0; i < multi->num_clients && inst_data[i].type; i++) {
		memset(&board_info, 0, sizeof(board_info));
		strlcpy(board_info.type, inst_data[i].type, I2C_NAME_SIZE);
		snprintf(name, sizeof(name), "%s-%s.%d", match->id,
			 inst_data[i].type, i);
		board_info.dev_name = name;
		switch (inst_data[i].flags & IRQ_RESOURCE_TYPE) {
		case IRQ_RESOURCE_GPIO:
			ret = acpi_dev_gpio_irq_get(adev, inst_data[i].irq_idx);
			if (ret < 0) {
				dev_err(dev, "Error requesting irq at index %d: %d\n",
					inst_data[i].irq_idx, ret);
				goto error;
			}
			board_info.irq = ret;
			break;
		case IRQ_RESOURCE_APIC:
			ret = platform_get_irq(pdev, inst_data[i].irq_idx);
			if (ret < 0) {
				dev_dbg(dev, "Error requesting irq at index %d: %d\n",
					inst_data[i].irq_idx, ret);
			}
			board_info.irq = ret;
			break;
		default:
			board_info.irq = 0;
			break;
		}
		multi->clients[i] = i2c_acpi_new_device(dev, i, &board_info);
		if (IS_ERR(multi->clients[i])) {
			ret = PTR_ERR(multi->clients[i]);
			if (ret != -EPROBE_DEFER)
				dev_err(dev, "Error creating i2c-client, idx %d\n", i);
			goto error;
		}
	}
	if (i < multi->num_clients) {
		dev_err(dev, "Error finding driver, idx %d\n", i);
		ret = -ENODEV;
		goto error;
	}

	platform_set_drvdata(pdev, multi);
	return 0;

error:
	while (--i >= 0)
		i2c_unregister_device(multi->clients[i]);

	return ret;
}

static int i2c_multi_inst_remove(struct platform_device *pdev)
{
	struct i2c_multi_inst_data *multi = platform_get_drvdata(pdev);
	int i;

	for (i = 0; i < multi->num_clients; i++)
		i2c_unregister_device(multi->clients[i]);

	return 0;
}

static const struct i2c_inst_data bsg1160_data[]  = {
	{ "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
	{ "bmc150_magn" },
	{ "bmg160" },
	{}
};

static const struct i2c_inst_data int3515_data[]  = {
	{ "tps6598x", IRQ_RESOURCE_APIC, 0 },
	{ "tps6598x", IRQ_RESOURCE_APIC, 1 },
	{ "tps6598x", IRQ_RESOURCE_APIC, 2 },
	{ "tps6598x", IRQ_RESOURCE_APIC, 3 },
	{}
};

/*
 * Note new device-ids must also be added to i2c_multi_instantiate_ids in
 * drivers/acpi/scan.c: acpi_device_enumeration_by_parent().
 */
static const struct acpi_device_id i2c_multi_inst_acpi_ids[] = {
	{ "BSG1160", (unsigned long)bsg1160_data },
	{ "INT3515", (unsigned long)int3515_data },
	{ }
};
MODULE_DEVICE_TABLE(acpi, i2c_multi_inst_acpi_ids);

static struct platform_driver i2c_multi_inst_driver = {
	.driver	= {
		.name = "I2C multi instantiate pseudo device driver",
		.acpi_match_table = ACPI_PTR(i2c_multi_inst_acpi_ids),
	},
	.probe = i2c_multi_inst_probe,
	.remove = i2c_multi_inst_remove,
};
module_platform_driver(i2c_multi_inst_driver);

MODULE_DESCRIPTION("I2C multi instantiate pseudo device driver");
MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
MODULE_LICENSE("GPL");
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// SPDX-License-Identifier: GPL-2.0-only
/*
 * drivers/acpi/device_pm.c - ACPI device power management routines.
 *
 * Copyright (C) 2012, Intel Corp.
 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */

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

#include "internal.h"

#define _COMPONENT	ACPI_POWER_COMPONENT
ACPI_MODULE_NAME("device_pm");

/**
 * 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:
		return "D3cold";
	default:
		return "(unknown)";
	}
}

static int acpi_dev_pm_explicit_get(struct acpi_device *device, int *state)
{
	unsigned long long psc;
	acpi_status status;

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

	*state = psc;
	return 0;
}

/**
 * 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).
 *
 * Also, it does not update power resource reference counters to ensure that
 * the power state returned by it will be persistent and it may return a power
 * state shallower than previously set by acpi_device_set_power() for @device
 * (if that power state depends on any power resources).
 */
int acpi_device_get_power(struct acpi_device *device, int *state)
{
	int result = ACPI_STATE_UNKNOWN;
	int error;

	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;
	}

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

		error = acpi_dev_pm_explicit_get(device, &psc);
		if (error)
			return error;

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

	/*
	 * 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
	 * to be in D0 too, except if ignore_parent is set.
	 */
	if (!device->power.flags.ignore_parent && device->parent
	    && device->parent->power.state == ACPI_STATE_UNKNOWN
	    && 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;
}

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;
}

/**
 * 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)
{
	int target_state = state;
	int result = 0;

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

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

	/* There is a special case for D0 addressed below. */
	if (state > ACPI_STATE_D0 && state == device->power.state) {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already in %s\n",
				  device->pnp.bus_id,
				  acpi_power_state_string(state)));
		return 0;
	}

	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) {
		dev_warn(&device->dev, "Power state %s not supported\n",
			 acpi_power_state_string(state));
		return -ENODEV;
	}

	if (!device->power.flags.ignore_parent &&
	    device->parent && (state < device->parent->power.state)) {
		dev_warn(&device->dev,
			 "Cannot transition to power state %s for parent in %s\n",
			 acpi_power_state_string(state),
			 acpi_power_state_string(device->parent->power.state));
		return -ENODEV;
	}

	/*
	 * Transition Power
	 * ----------------
	 * 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.
	 */
	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;
		}

		/*
		 * If the device goes from D3hot to D3cold, _PS3 has been
		 * evaluated for it already, so skip it in that case.
		 */
		if (device->power.state < ACPI_STATE_D3_HOT) {
			result = acpi_dev_pm_explicit_set(device, state);
			if (result)
				goto end;
		}

		if (device->power.flags.power_resources)
			result = acpi_power_transition(device, target_state);
	} else {
		int cur_state = device->power.state;

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

		if (cur_state == ACPI_STATE_D0) {
			int psc;

			/* Nothing to do here if _PSC is not present. */
			if (!device->power.flags.explicit_get)
				return 0;

			/*
			 * The power state of the device was set to D0 last
			 * time, but that might have happened before a
			 * system-wide transition involving the platform
			 * firmware, so it may be necessary to evaluate _PS0
			 * for the device here.  However, use extra care here
			 * and evaluate _PSC to check the device's current power
			 * state, and only invoke _PS0 if the evaluation of _PSC
			 * is successful and it returns a power state different
			 * from D0.
			 */
			result = acpi_dev_pm_explicit_get(device, &psc);
			if (result || psc == ACPI_STATE_D0)
				return 0;
		}

		result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
	}

 end:
	if (result) {
		dev_warn(&device->dev, "Failed to change power state to %s\n",
			 acpi_power_state_string(state));
	} else {
		device->power.state = target_state;
		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;
	if (!acpi_device_is_present(device)) {
		device->flags.initialized = false;
		return -ENXIO;
	}

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

	if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {
		/* Reference count the power resources. */
		result = acpi_power_on_resources(device, state);
		if (result)
			return result;

		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;
		}
	} else if (state == ACPI_STATE_UNKNOWN) {
		/*
		 * 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.]
		 */
		state = ACPI_STATE_D0;
	}
	device->power.state = state;
	return 0;
}

/**
 * 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;
}
EXPORT_SYMBOL_GPL(acpi_device_fix_up_power);

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

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

		return result;
	}

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

	if (state == ACPI_STATE_UNKNOWN) {
		state = ACPI_STATE_D0;
		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)
		*state_p = state;

	return 0;
}
EXPORT_SYMBOL_GPL(acpi_device_update_power);

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);
}
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);

#ifdef CONFIG_PM
static DEFINE_MUTEX(acpi_pm_notifier_lock);
static DEFINE_MUTEX(acpi_pm_notifier_install_lock);

void acpi_pm_wakeup_event(struct device *dev)
{
	pm_wakeup_dev_event(dev, 0, acpi_s2idle_wakeup());
}
EXPORT_SYMBOL_GPL(acpi_pm_wakeup_event);

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;

	acpi_handle_debug(handle, "Wake notify\n");

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

	mutex_lock(&acpi_pm_notifier_lock);

	if (adev->wakeup.flags.notifier_present) {
		pm_wakeup_ws_event(adev->wakeup.ws, 0, acpi_s2idle_wakeup());
		if (adev->wakeup.context.func) {
			acpi_handle_debug(handle, "Running %pS for %s\n",
					  adev->wakeup.context.func,
					  dev_name(adev->wakeup.context.dev));
			adev->wakeup.context.func(&adev->wakeup.context);
		}
	}

	mutex_unlock(&acpi_pm_notifier_lock);

	acpi_bus_put_acpi_device(adev);
}

/**
 * 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.
 * @func: Work function to execute when handling the notification.
 *
 * 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.
 */
acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev,
			void (*func)(struct acpi_device_wakeup_context *context))
{
	acpi_status status = AE_ALREADY_EXISTS;

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

	mutex_lock(&acpi_pm_notifier_install_lock);

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

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

	mutex_lock(&acpi_pm_notifier_lock);
	adev->wakeup.ws = wakeup_source_register(dev_name(&adev->dev));
	adev->wakeup.context.dev = dev;
	adev->wakeup.context.func = func;
	adev->wakeup.flags.notifier_present = true;
	mutex_unlock(&acpi_pm_notifier_lock);

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

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

	mutex_lock(&acpi_pm_notifier_install_lock);

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

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

	mutex_lock(&acpi_pm_notifier_lock);
	adev->wakeup.context.func = NULL;
	adev->wakeup.context.dev = NULL;
	wakeup_source_unregister(adev->wakeup.ws);
	adev->wakeup.flags.notifier_present = false;
	mutex_unlock(&acpi_pm_notifier_lock);

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

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);

bool acpi_pm_device_can_wakeup(struct device *dev)
{
	struct acpi_device *adev = ACPI_COMPANION(dev);

	return adev ? acpi_device_can_wakeup(adev) : false;
}

/**
 * acpi_dev_pm_get_state - Get preferred power state of ACPI device.
 * @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.
 * @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.
 *
 * 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.
 *
 * Callers must ensure that @dev and @adev are valid pointers and that @adev
 * actually corresponds to @dev before using this function.
 *
 * 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.
 */
static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev,
				 u32 target_state, int *d_min_p, int *d_max_p)
{
	char method[] = { '_', 'S', '0' + target_state, 'D', '\0' };
	acpi_handle handle = adev->handle;
	unsigned long long ret;
	int d_min, d_max;
	bool wakeup = false;
	bool has_sxd = false;
	acpi_status status;

	/*
	 * 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.
	 */
	d_min = ACPI_STATE_D0;
	d_max = ACPI_STATE_D3_COLD;

	/*
	 * 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) {
		/*
		 * 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;
		}

		if (status == AE_OK)
			has_sxd = true;

		d_min = ret;
		wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
			&& adev->wakeup.sleep_state >= target_state;
	} else {
		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) {
		method[3] = 'W';
		status = acpi_evaluate_integer(handle, method, NULL, &ret);
		if (status == AE_NOT_FOUND) {
			/* No _SxW. In this case, the ACPI spec says that we
			 * must not go into any power state deeper than the
			 * value returned from _SxD.
			 */
			if (has_sxd && target_state > ACPI_STATE_S0)
				d_max = d_min;
		} 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;
		}
	}

	if (d_min_p)
		*d_min_p = d_min;

	if (d_max_p)
		*d_max_p = d_max;

	return 0;
}

/**
 * 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
 * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is
 * incorrect, or -ENODATA on ACPI method failure.
 *
 * 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;
	int ret, d_min, d_max;

	if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD)
		return -EINVAL;

	if (d_max_in > ACPI_STATE_D2) {
		enum pm_qos_flags_status stat;

		stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);