[linux-2.6-block.git] / drivers / acpi / thermal_lib.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright 2023 Linaro Limited
 * Copyright 2023 Intel Corporation
 *
 * Library routines for retrieving trip point temperature values from the
 * platform firmware via ACPI.
 */
#include <linux/acpi.h>
#include <linux/units.h>
#include <linux/thermal.h>
#include "internal.h"

/*
 * Minimum temperature for full military grade is 218°K (-55°C) and
 * max temperature is 448°K (175°C). We can consider those values as
 * the boundaries for the [trips] temperature returned by the
 * firmware. Any values out of these boundaries may be considered
 * bogus and we can assume the firmware has no data to provide.
 */
#define TEMP_MIN_DECIK	2180ULL
#define TEMP_MAX_DECIK	4480ULL

static int acpi_trip_temp(struct acpi_device *adev, char *obj_name,
			  int *ret_temp)
{
	unsigned long long temp;
	acpi_status status;

	status = acpi_evaluate_integer(adev->handle, obj_name, NULL, &temp);
	if (ACPI_FAILURE(status)) {
		acpi_handle_debug(adev->handle, "%s evaluation failed\n", obj_name);
		return -ENODATA;
	}

	if (temp >= TEMP_MIN_DECIK && temp <= TEMP_MAX_DECIK) {
		*ret_temp = temp;
	} else {
		acpi_handle_debug(adev->handle, "%s result %llu out of range\n",
				  obj_name, temp);
		*ret_temp = THERMAL_TEMP_INVALID;
	}

	return 0;
}

int acpi_active_trip_temp(struct acpi_device *adev, int id, int *ret_temp)
{
	char obj_name[] = {'_', 'A', 'C', '0' + id, '\0'};

	if (id < 0 || id > 9)
		return -EINVAL;

	return acpi_trip_temp(adev, obj_name, ret_temp);
}
EXPORT_SYMBOL_NS_GPL(acpi_active_trip_temp, ACPI_THERMAL);

int acpi_passive_trip_temp(struct acpi_device *adev, int *ret_temp)
{
	return acpi_trip_temp(adev, "_PSV", ret_temp);
}
EXPORT_SYMBOL_NS_GPL(acpi_passive_trip_temp, ACPI_THERMAL);

int acpi_hot_trip_temp(struct acpi_device *adev, int *ret_temp)
{
	return acpi_trip_temp(adev, "_HOT", ret_temp);
}
EXPORT_SYMBOL_NS_GPL(acpi_hot_trip_temp, ACPI_THERMAL);

int acpi_critical_trip_temp(struct acpi_device *adev, int *ret_temp)
{
	return acpi_trip_temp(adev, "_CRT", ret_temp);
}
EXPORT_SYMBOL_NS_GPL(acpi_critical_trip_temp, ACPI_THERMAL);

static int thermal_temp(int error, int temp_decik, int *ret_temp)
{
	if (error)
		return error;

	if (temp_decik == THERMAL_TEMP_INVALID)
		*ret_temp = THERMAL_TEMP_INVALID;
	else
		*ret_temp = deci_kelvin_to_millicelsius(temp_decik);

	return 0;
}

/**
 * thermal_acpi_active_trip_temp - Retrieve active trip point temperature
 * @adev: Target thermal zone ACPI device object.
 * @id: Active cooling level (0 - 9).
 * @ret_temp: Address to store the retrieved temperature value on success.
 *
 * Evaluate the _ACx object for the thermal zone represented by @adev to obtain
 * the temperature of the active cooling trip point corresponding to the active
 * cooling level given by @id.
 *
 * Return 0 on success or a negative error value on failure.
 */
int thermal_acpi_active_trip_temp(struct acpi_device *adev, int id, int *ret_temp)
{
	int temp_decik;
	int ret = acpi_active_trip_temp(adev, id, &temp_decik);

	return thermal_temp(ret, temp_decik, ret_temp);
}
EXPORT_SYMBOL_GPL(thermal_acpi_active_trip_temp);

/**
 * thermal_acpi_passive_trip_temp - Retrieve passive trip point temperature
 * @adev: Target thermal zone ACPI device object.
 * @ret_temp: Address to store the retrieved temperature value on success.
 *
 * Evaluate the _PSV object for the thermal zone represented by @adev to obtain
 * the temperature of the passive cooling trip point.
 *
 * Return 0 on success or -ENODATA on failure.
 */
int thermal_acpi_passive_trip_temp(struct acpi_device *adev, int *ret_temp)
{
	int temp_decik;
	int ret = acpi_passive_trip_temp(adev, &temp_decik);

	return thermal_temp(ret, temp_decik, ret_temp);
}
EXPORT_SYMBOL_GPL(thermal_acpi_passive_trip_temp);

/**
 * thermal_acpi_hot_trip_temp - Retrieve hot trip point temperature
 * @adev: Target thermal zone ACPI device object.
 * @ret_temp: Address to store the retrieved temperature value on success.
 *
 * Evaluate the _HOT object for the thermal zone represented by @adev to obtain
 * the temperature of the trip point at which the system is expected to be put
 * into the S4 sleep state.
 *
 * Return 0 on success or -ENODATA on failure.
 */
int thermal_acpi_hot_trip_temp(struct acpi_device *adev, int *ret_temp)
{
	int temp_decik;
	int ret = acpi_hot_trip_temp(adev, &temp_decik);

	return thermal_temp(ret, temp_decik, ret_temp);
}
EXPORT_SYMBOL_GPL(thermal_acpi_hot_trip_temp);

/**
 * thermal_acpi_critical_trip_temp - Retrieve critical trip point temperature
 * @adev: Target thermal zone ACPI device object.
 * @ret_temp: Address to store the retrieved temperature value on success.
 *
 * Evaluate the _CRT object for the thermal zone represented by @adev to obtain
 * the temperature of the critical cooling trip point.
 *
 * Return 0 on success or -ENODATA on failure.
 */
int thermal_acpi_critical_trip_temp(struct acpi_device *adev, int *ret_temp)
{
	int temp_decik;
	int ret = acpi_critical_trip_temp(adev, &temp_decik);

	return thermal_temp(ret, temp_decik, ret_temp);
}
EXPORT_SYMBOL_GPL(thermal_acpi_critical_trip_temp);
Commit	Line	Data
7a0e3974 RW	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	* Copyright 2023 Linaro Limited
	4	* Copyright 2023 Intel Corporation
	5	*
6908097a RW	6	* Library routines for retrieving trip point temperature values from the
6908097a RW	7	* platform firmware via ACPI.
7a0e3974 RW	8	*/
	9	#include <linux/acpi.h>
	10	#include <linux/units.h>
c27d08f7	11	#include <linux/thermal.h>
b14b2d56	12	#include "internal.h"
7a0e3974 RW	13
	14	/*
	15	* Minimum temperature for full military grade is 218°K (-55°C) and
	16	* max temperature is 448°K (175°C). We can consider those values as
	17	* the boundaries for the [trips] temperature returned by the
	18	* firmware. Any values out of these boundaries may be considered
	19	* bogus and we can assume the firmware has no data to provide.
	20	*/
6908097a RW	21	#define TEMP_MIN_DECIK 2180ULL
6908097a RW	22	#define TEMP_MAX_DECIK 4480ULL
7a0e3974	23
6908097a RW	24	static int acpi_trip_temp(struct acpi_device adev, char obj_name,
6908097a RW	25	int *ret_temp)
7a0e3974 RW	26	{
	27	unsigned long long temp;
	28	acpi_status status;
7a0e3974 RW	29
	30	status = acpi_evaluate_integer(adev->handle, obj_name, NULL, &temp);
	31	if (ACPI_FAILURE(status)) {
	32	acpi_handle_debug(adev->handle, "%s evaluation failed\n", obj_name);
	33	return -ENODATA;
	34	}
	35
97efecfd	36	if (temp >= TEMP_MIN_DECIK && temp <= TEMP_MAX_DECIK) {
6908097a	37	*ret_temp = temp;
97efecfd	38	} else {
7a0e3974 RW	39	acpi_handle_debug(adev->handle, "%s result %llu out of range\n",
7a0e3974 RW	40	obj_name, temp);
dd3b3d16	41	*ret_temp = THERMAL_TEMP_INVALID;
7a0e3974 RW	42	}
7a0e3974 RW	43
7a0e3974 RW	44	return 0;
	45	}
	46
6908097a RW	47	int acpi_active_trip_temp(struct acpi_device adev, int id, int ret_temp)
	48	{
	49	char obj_name[] = {'_', 'A', 'C', '0' + id, '\0'};
	50
	51	if (id < 0 \|\| id > 9)
	52	return -EINVAL;
	53
	54	return acpi_trip_temp(adev, obj_name, ret_temp);
	55	}
9c864722	56	EXPORT_SYMBOL_NS_GPL(acpi_active_trip_temp, ACPI_THERMAL);
6908097a RW	57
	58	int acpi_passive_trip_temp(struct acpi_device adev, int ret_temp)
	59	{
	60	return acpi_trip_temp(adev, "_PSV", ret_temp);
	61	}
9c864722	62	EXPORT_SYMBOL_NS_GPL(acpi_passive_trip_temp, ACPI_THERMAL);
6908097a RW	63
	64	int acpi_hot_trip_temp(struct acpi_device adev, int ret_temp)
	65	{
	66	return acpi_trip_temp(adev, "_HOT", ret_temp);
	67	}
9c864722	68	EXPORT_SYMBOL_NS_GPL(acpi_hot_trip_temp, ACPI_THERMAL);
6908097a RW	69
	70	int acpi_critical_trip_temp(struct acpi_device adev, int ret_temp)
	71	{
	72	return acpi_trip_temp(adev, "_CRT", ret_temp);
	73	}
9c864722	74	EXPORT_SYMBOL_NS_GPL(acpi_critical_trip_temp, ACPI_THERMAL);
6908097a RW	75
	76	static int thermal_temp(int error, int temp_decik, int *ret_temp)
	77	{
	78	if (error)
	79	return error;
	80
	81	if (temp_decik == THERMAL_TEMP_INVALID)
	82	*ret_temp = THERMAL_TEMP_INVALID;
	83	else
	84	*ret_temp = deci_kelvin_to_millicelsius(temp_decik);
	85
	86	return 0;
	87	}
	88
7a0e3974	89	/**
dd3b3d16 RW	90	* thermal_acpi_active_trip_temp - Retrieve active trip point temperature
dd3b3d16 RW	91	* @adev: Target thermal zone ACPI device object.
7a0e3974	92	* @id: Active cooling level (0 - 9).
dd3b3d16	93	* @ret_temp: Address to store the retrieved temperature value on success.
7a0e3974 RW	94	*
	95	* Evaluate the _ACx object for the thermal zone represented by @adev to obtain
	96	* the temperature of the active cooling trip point corresponding to the active
dd3b3d16	97	* cooling level given by @id.
7a0e3974 RW	98	*
	99	* Return 0 on success or a negative error value on failure.
	100	*/
dd3b3d16	101	int thermal_acpi_active_trip_temp(struct acpi_device adev, int id, int ret_temp)
7a0e3974	102	{
6908097a RW	103	int temp_decik;
6908097a RW	104	int ret = acpi_active_trip_temp(adev, id, &temp_decik);
dd3b3d16	105
6908097a	106	return thermal_temp(ret, temp_decik, ret_temp);
7a0e3974	107	}
dd3b3d16	108	EXPORT_SYMBOL_GPL(thermal_acpi_active_trip_temp);
7a0e3974 RW	109
7a0e3974 RW	110	/**
dd3b3d16 RW	111	* thermal_acpi_passive_trip_temp - Retrieve passive trip point temperature
	112	* @adev: Target thermal zone ACPI device object.
	113	* @ret_temp: Address to store the retrieved temperature value on success.
7a0e3974 RW	114	*
7a0e3974 RW	115	* Evaluate the _PSV object for the thermal zone represented by @adev to obtain
dd3b3d16	116	* the temperature of the passive cooling trip point.
7a0e3974 RW	117	*
	118	* Return 0 on success or -ENODATA on failure.
	119	*/
dd3b3d16	120	int thermal_acpi_passive_trip_temp(struct acpi_device adev, int ret_temp)
7a0e3974	121	{
6908097a RW	122	int temp_decik;
	123	int ret = acpi_passive_trip_temp(adev, &temp_decik);
	124
	125	return thermal_temp(ret, temp_decik, ret_temp);
7a0e3974	126	}
dd3b3d16	127	EXPORT_SYMBOL_GPL(thermal_acpi_passive_trip_temp);
7a0e3974 RW	128
7a0e3974 RW	129	/**
dd3b3d16 RW	130	* thermal_acpi_hot_trip_temp - Retrieve hot trip point temperature
	131	* @adev: Target thermal zone ACPI device object.
	132	* @ret_temp: Address to store the retrieved temperature value on success.
7a0e3974 RW	133	*
	134	* Evaluate the _HOT object for the thermal zone represented by @adev to obtain
	135	* the temperature of the trip point at which the system is expected to be put
dd3b3d16	136	* into the S4 sleep state.
7a0e3974 RW	137	*
	138	* Return 0 on success or -ENODATA on failure.
	139	*/
dd3b3d16	140	int thermal_acpi_hot_trip_temp(struct acpi_device adev, int ret_temp)
7a0e3974	141	{
6908097a RW	142	int temp_decik;
	143	int ret = acpi_hot_trip_temp(adev, &temp_decik);
	144
	145	return thermal_temp(ret, temp_decik, ret_temp);
7a0e3974	146	}
dd3b3d16	147	EXPORT_SYMBOL_GPL(thermal_acpi_hot_trip_temp);
7a0e3974 RW	148
7a0e3974 RW	149	/**
dd3b3d16 RW	150	* thermal_acpi_critical_trip_temp - Retrieve critical trip point temperature
	151	* @adev: Target thermal zone ACPI device object.
	152	* @ret_temp: Address to store the retrieved temperature value on success.
7a0e3974 RW	153	*
7a0e3974 RW	154	* Evaluate the _CRT object for the thermal zone represented by @adev to obtain
dd3b3d16	155	* the temperature of the critical cooling trip point.
7a0e3974 RW	156	*
	157	* Return 0 on success or -ENODATA on failure.
	158	*/
dd3b3d16	159	int thermal_acpi_critical_trip_temp(struct acpi_device adev, int ret_temp)
7a0e3974	160	{
6908097a RW	161	int temp_decik;
	162	int ret = acpi_critical_trip_temp(adev, &temp_decik);
	163
	164	return thermal_temp(ret, temp_decik, ret_temp);
7a0e3974	165	}
dd3b3d16	166	EXPORT_SYMBOL_GPL(thermal_acpi_critical_trip_temp);