Commit 7a0e3974 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki

thermal: ACPI: Add ACPI trip point routines

Add library routines to populate a generic thermal trip point
structure with data obtained by evaluating a specific object in the
ACPI Namespace.
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Co-developed-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
Tested-by: default avatarSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
parent 40dc1929
......@@ -76,6 +76,10 @@ config THERMAL_OF
Say 'Y' here if you need to build thermal infrastructure
based on device tree.
config THERMAL_ACPI
depends on ACPI
bool
config THERMAL_WRITABLE_TRIPS
bool "Enable writable trip points"
help
......
......@@ -13,6 +13,7 @@ thermal_sys-$(CONFIG_THERMAL_NETLINK) += thermal_netlink.o
# interface to/from other layers providing sensors
thermal_sys-$(CONFIG_THERMAL_HWMON) += thermal_hwmon.o
thermal_sys-$(CONFIG_THERMAL_OF) += thermal_of.o
thermal_sys-$(CONFIG_THERMAL_ACPI) += thermal_acpi.o
# governors
thermal_sys-$(CONFIG_THERMAL_GOV_FAIR_SHARE) += gov_fair_share.o
......
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright 2023 Linaro Limited
* Copyright 2023 Intel Corporation
*
* Library routines for populating a generic thermal trip point structure
* with data obtained by evaluating a specific object in the ACPI Namespace.
*/
#include <linux/acpi.h>
#include <linux/units.h>
#include "thermal_core.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 2180
#define TEMP_MAX_DECIK 4480
static int thermal_acpi_trip_init(struct acpi_device *adev,
enum thermal_trip_type type, int id,
struct thermal_trip *trip)
{
unsigned long long temp;
acpi_status status;
char obj_name[5];
switch (type) {
case THERMAL_TRIP_ACTIVE:
if (id < 0 || id > 9)
return -EINVAL;
obj_name[1] = 'A';
obj_name[2] = 'C';
obj_name[3] = '0' + id;
break;
case THERMAL_TRIP_PASSIVE:
obj_name[1] = 'P';
obj_name[2] = 'S';
obj_name[3] = 'V';
break;
case THERMAL_TRIP_HOT:
obj_name[1] = 'H';
obj_name[2] = 'O';
obj_name[3] = 'T';
break;
case THERMAL_TRIP_CRITICAL:
obj_name[1] = 'C';
obj_name[2] = 'R';
obj_name[3] = 'T';
break;
}
obj_name[0] = '_';
obj_name[4] = '\0';
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) {
acpi_handle_debug(adev->handle, "%s result %llu out of range\n",
obj_name, temp);
return -ENODATA;
}
trip->temperature = deci_kelvin_to_millicelsius(temp);
trip->hysteresis = 0;
trip->type = type;
return 0;
}
/**
* thermal_acpi_trip_active - Get the specified active trip point
* @adev: Thermal zone ACPI device object to get the description from.
* @id: Active cooling level (0 - 9).
* @trip: Trip point structure to be populated 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 and initialize @trip as an active trip point using
* that temperature value.
*
* Return 0 on success or a negative error value on failure.
*/
int thermal_acpi_trip_active(struct acpi_device *adev, int id,
struct thermal_trip *trip)
{
return thermal_acpi_trip_init(adev, THERMAL_TRIP_ACTIVE, id, trip);
}
EXPORT_SYMBOL_GPL(thermal_acpi_trip_active);
/**
* thermal_acpi_trip_passive - Get the passive trip point
* @adev: Thermal zone ACPI device object to get the description from.
* @trip: Trip point structure to be populated on success.
*
* Evaluate the _PSV object for the thermal zone represented by @adev to obtain
* the temperature of the passive cooling trip point and initialize @trip as a
* passive trip point using that temperature value.
*
* Return 0 on success or -ENODATA on failure.
*/
int thermal_acpi_trip_passive(struct acpi_device *adev, struct thermal_trip *trip)
{
return thermal_acpi_trip_init(adev, THERMAL_TRIP_PASSIVE, INT_MAX, trip);
}
EXPORT_SYMBOL_GPL(thermal_acpi_trip_passive);
/**
* thermal_acpi_trip_hot - Get the near critical trip point
* @adev: the ACPI device to get the description from.
* @trip: a &struct thermal_trip to be filled if the function succeed.
*
* 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 and initialize @trip as a hot trip point using that
* temperature value.
*
* Return 0 on success or -ENODATA on failure.
*/
int thermal_acpi_trip_hot(struct acpi_device *adev, struct thermal_trip *trip)
{
return thermal_acpi_trip_init(adev, THERMAL_TRIP_HOT, INT_MAX, trip);
}
EXPORT_SYMBOL_GPL(thermal_acpi_trip_hot);
/**
* thermal_acpi_trip_critical - Get the critical trip point
* @adev: the ACPI device to get the description from.
* @trip: a &struct thermal_trip to be filled if the function succeed.
*
* Evaluate the _CRT object for the thermal zone represented by @adev to obtain
* the temperature of the critical cooling trip point and initialize @trip as a
* critical trip point using that temperature value.
*
* Return 0 on success or -ENODATA on failure.
*/
int thermal_acpi_trip_critical(struct acpi_device *adev, struct thermal_trip *trip)
{
return thermal_acpi_trip_init(adev, THERMAL_TRIP_CRITICAL, INT_MAX, trip);
}
EXPORT_SYMBOL_GPL(thermal_acpi_trip_critical);
......@@ -346,6 +346,14 @@ int thermal_zone_get_num_trips(struct thermal_zone_device *tz);
int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp);
#ifdef CONFIG_THERMAL_ACPI
int thermal_acpi_trip_active(struct acpi_device *adev, int id,
struct thermal_trip *trip);
int thermal_acpi_trip_passive(struct acpi_device *adev, struct thermal_trip *trip);
int thermal_acpi_trip_hot(struct acpi_device *adev, struct thermal_trip *trip);
int thermal_acpi_trip_critical(struct acpi_device *adev, struct thermal_trip *trip);
#endif
#ifdef CONFIG_THERMAL
struct thermal_zone_device *thermal_zone_device_register(const char *, int, int,
void *, struct thermal_zone_device_ops *,
......
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