mirror of
https://github.com/torvalds/linux.git
synced 2024-12-05 10:32:35 +00:00
b70dbf40eb
There is a need to have a helper function which updates cooling device state from the governors code. With this change governor can use lock and unlock while calling helper function. This avoid unnecessary second time lock/unlock which was in previous solution present in governor implementation. This new helper function must be called with mutex 'cdev->lock' hold. The changed been discussed and part of code presented in thread: https://lore.kernel.org/linux-pm/20210419084536.25000-1-lukasz.luba@arm.com/ Co-developed-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Link: https://lore.kernel.org/r/20210422114308.29684-2-lukasz.luba@arm.com
262 lines
6.6 KiB
C
262 lines
6.6 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* thermal_helpers.c - helper functions to handle thermal devices
|
|
*
|
|
* Copyright (C) 2016 Eduardo Valentin <edubezval@gmail.com>
|
|
*
|
|
* Highly based on original thermal_core.c
|
|
* Copyright (C) 2008 Intel Corp
|
|
* Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
|
|
* Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
|
|
*/
|
|
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/err.h>
|
|
#include <linux/export.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/string.h>
|
|
#include <linux/sysfs.h>
|
|
|
|
#include <trace/events/thermal.h>
|
|
|
|
#include "thermal_core.h"
|
|
|
|
int get_tz_trend(struct thermal_zone_device *tz, int trip)
|
|
{
|
|
enum thermal_trend trend;
|
|
|
|
if (tz->emul_temperature || !tz->ops->get_trend ||
|
|
tz->ops->get_trend(tz, trip, &trend)) {
|
|
if (tz->temperature > tz->last_temperature)
|
|
trend = THERMAL_TREND_RAISING;
|
|
else if (tz->temperature < tz->last_temperature)
|
|
trend = THERMAL_TREND_DROPPING;
|
|
else
|
|
trend = THERMAL_TREND_STABLE;
|
|
}
|
|
|
|
return trend;
|
|
}
|
|
EXPORT_SYMBOL(get_tz_trend);
|
|
|
|
struct thermal_instance *
|
|
get_thermal_instance(struct thermal_zone_device *tz,
|
|
struct thermal_cooling_device *cdev, int trip)
|
|
{
|
|
struct thermal_instance *pos = NULL;
|
|
struct thermal_instance *target_instance = NULL;
|
|
|
|
mutex_lock(&tz->lock);
|
|
mutex_lock(&cdev->lock);
|
|
|
|
list_for_each_entry(pos, &tz->thermal_instances, tz_node) {
|
|
if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
|
|
target_instance = pos;
|
|
break;
|
|
}
|
|
}
|
|
|
|
mutex_unlock(&cdev->lock);
|
|
mutex_unlock(&tz->lock);
|
|
|
|
return target_instance;
|
|
}
|
|
EXPORT_SYMBOL(get_thermal_instance);
|
|
|
|
/**
|
|
* thermal_zone_get_temp() - returns the temperature of a thermal zone
|
|
* @tz: a valid pointer to a struct thermal_zone_device
|
|
* @temp: a valid pointer to where to store the resulting temperature.
|
|
*
|
|
* When a valid thermal zone reference is passed, it will fetch its
|
|
* temperature and fill @temp.
|
|
*
|
|
* Return: On success returns 0, an error code otherwise
|
|
*/
|
|
int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp)
|
|
{
|
|
int ret = -EINVAL;
|
|
int count;
|
|
int crit_temp = INT_MAX;
|
|
enum thermal_trip_type type;
|
|
|
|
if (!tz || IS_ERR(tz) || !tz->ops->get_temp)
|
|
goto exit;
|
|
|
|
mutex_lock(&tz->lock);
|
|
|
|
ret = tz->ops->get_temp(tz, temp);
|
|
|
|
if (IS_ENABLED(CONFIG_THERMAL_EMULATION) && tz->emul_temperature) {
|
|
for (count = 0; count < tz->trips; count++) {
|
|
ret = tz->ops->get_trip_type(tz, count, &type);
|
|
if (!ret && type == THERMAL_TRIP_CRITICAL) {
|
|
ret = tz->ops->get_trip_temp(tz, count,
|
|
&crit_temp);
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Only allow emulating a temperature when the real temperature
|
|
* is below the critical temperature so that the emulation code
|
|
* cannot hide critical conditions.
|
|
*/
|
|
if (!ret && *temp < crit_temp)
|
|
*temp = tz->emul_temperature;
|
|
}
|
|
|
|
mutex_unlock(&tz->lock);
|
|
exit:
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(thermal_zone_get_temp);
|
|
|
|
/**
|
|
* thermal_zone_set_trips - Computes the next trip points for the driver
|
|
* @tz: a pointer to a thermal zone device structure
|
|
*
|
|
* The function computes the next temperature boundaries by browsing
|
|
* the trip points. The result is the closer low and high trip points
|
|
* to the current temperature. These values are passed to the backend
|
|
* driver to let it set its own notification mechanism (usually an
|
|
* interrupt).
|
|
*
|
|
* It does not return a value
|
|
*/
|
|
void thermal_zone_set_trips(struct thermal_zone_device *tz)
|
|
{
|
|
int low = -INT_MAX;
|
|
int high = INT_MAX;
|
|
int trip_temp, hysteresis;
|
|
int i, ret;
|
|
|
|
mutex_lock(&tz->lock);
|
|
|
|
if (!tz->ops->set_trips || !tz->ops->get_trip_hyst)
|
|
goto exit;
|
|
|
|
for (i = 0; i < tz->trips; i++) {
|
|
int trip_low;
|
|
|
|
tz->ops->get_trip_temp(tz, i, &trip_temp);
|
|
tz->ops->get_trip_hyst(tz, i, &hysteresis);
|
|
|
|
trip_low = trip_temp - hysteresis;
|
|
|
|
if (trip_low < tz->temperature && trip_low > low)
|
|
low = trip_low;
|
|
|
|
if (trip_temp > tz->temperature && trip_temp < high)
|
|
high = trip_temp;
|
|
}
|
|
|
|
/* No need to change trip points */
|
|
if (tz->prev_low_trip == low && tz->prev_high_trip == high)
|
|
goto exit;
|
|
|
|
tz->prev_low_trip = low;
|
|
tz->prev_high_trip = high;
|
|
|
|
dev_dbg(&tz->device,
|
|
"new temperature boundaries: %d < x < %d\n", low, high);
|
|
|
|
/*
|
|
* Set a temperature window. When this window is left the driver
|
|
* must inform the thermal core via thermal_zone_device_update.
|
|
*/
|
|
ret = tz->ops->set_trips(tz, low, high);
|
|
if (ret)
|
|
dev_err(&tz->device, "Failed to set trips: %d\n", ret);
|
|
|
|
exit:
|
|
mutex_unlock(&tz->lock);
|
|
}
|
|
|
|
void thermal_set_delay_jiffies(unsigned long *delay_jiffies, int delay_ms)
|
|
{
|
|
*delay_jiffies = msecs_to_jiffies(delay_ms);
|
|
if (delay_ms > 1000)
|
|
*delay_jiffies = round_jiffies(*delay_jiffies);
|
|
}
|
|
|
|
static void thermal_cdev_set_cur_state(struct thermal_cooling_device *cdev,
|
|
int target)
|
|
{
|
|
if (cdev->ops->set_cur_state(cdev, target))
|
|
return;
|
|
|
|
thermal_notify_cdev_state_update(cdev->id, target);
|
|
thermal_cooling_device_stats_update(cdev, target);
|
|
}
|
|
|
|
void __thermal_cdev_update(struct thermal_cooling_device *cdev)
|
|
{
|
|
struct thermal_instance *instance;
|
|
unsigned long target = 0;
|
|
|
|
/* Make sure cdev enters the deepest cooling state */
|
|
list_for_each_entry(instance, &cdev->thermal_instances, cdev_node) {
|
|
dev_dbg(&cdev->device, "zone%d->target=%lu\n",
|
|
instance->tz->id, instance->target);
|
|
if (instance->target == THERMAL_NO_TARGET)
|
|
continue;
|
|
if (instance->target > target)
|
|
target = instance->target;
|
|
}
|
|
|
|
thermal_cdev_set_cur_state(cdev, target);
|
|
|
|
trace_cdev_update(cdev, target);
|
|
dev_dbg(&cdev->device, "set to state %lu\n", target);
|
|
}
|
|
|
|
/**
|
|
* thermal_cdev_update - update cooling device state if needed
|
|
* @cdev: pointer to struct thermal_cooling_device
|
|
*
|
|
* Update the cooling device state if there is a need.
|
|
*/
|
|
void thermal_cdev_update(struct thermal_cooling_device *cdev)
|
|
{
|
|
mutex_lock(&cdev->lock);
|
|
if (!cdev->updated) {
|
|
__thermal_cdev_update(cdev);
|
|
cdev->updated = true;
|
|
}
|
|
mutex_unlock(&cdev->lock);
|
|
}
|
|
EXPORT_SYMBOL(thermal_cdev_update);
|
|
|
|
/**
|
|
* thermal_zone_get_slope - return the slope attribute of the thermal zone
|
|
* @tz: thermal zone device with the slope attribute
|
|
*
|
|
* Return: If the thermal zone device has a slope attribute, return it, else
|
|
* return 1.
|
|
*/
|
|
int thermal_zone_get_slope(struct thermal_zone_device *tz)
|
|
{
|
|
if (tz && tz->tzp)
|
|
return tz->tzp->slope;
|
|
return 1;
|
|
}
|
|
EXPORT_SYMBOL_GPL(thermal_zone_get_slope);
|
|
|
|
/**
|
|
* thermal_zone_get_offset - return the offset attribute of the thermal zone
|
|
* @tz: thermal zone device with the offset attribute
|
|
*
|
|
* Return: If the thermal zone device has a offset attribute, return it, else
|
|
* return 0.
|
|
*/
|
|
int thermal_zone_get_offset(struct thermal_zone_device *tz)
|
|
{
|
|
if (tz && tz->tzp)
|
|
return tz->tzp->offset;
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(thermal_zone_get_offset);
|