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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2008 Intel Corp
* Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
* Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
* Copyright 2022 Linaro Limited
*
* Thermal trips handling
*/
#include "thermal_core.h"
int for_each_thermal_trip(struct thermal_zone_device *tz,
int (*cb)(struct thermal_trip *, void *),
void *data)
{
struct thermal_trip *trip;
int ret;
for_each_trip(tz, trip) {
ret = cb(trip, data);
if (ret)
return ret;
}
return 0;
}
EXPORT_SYMBOL_GPL(for_each_thermal_trip);
int thermal_zone_for_each_trip(struct thermal_zone_device *tz,
int (*cb)(struct thermal_trip *, void *),
void *data)
{
int ret;
mutex_lock(&tz->lock);
ret = for_each_thermal_trip(tz, cb, data);
mutex_unlock(&tz->lock);
return ret;
}
EXPORT_SYMBOL_GPL(thermal_zone_for_each_trip);
int thermal_zone_get_num_trips(struct thermal_zone_device *tz)
{
return tz->num_trips;
}
EXPORT_SYMBOL_GPL(thermal_zone_get_num_trips);
/**
* __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).
*
* This function must be called with tz->lock held. Both tz and tz->ops
* must be valid pointers.
*
* It does not return a value
*/
void __thermal_zone_set_trips(struct thermal_zone_device *tz)
{
const struct thermal_trip *trip;
int low = -INT_MAX, high = INT_MAX;
bool same_trip = false;
int ret;
lockdep_assert_held(&tz->lock);
if (!tz->ops->set_trips)
return;
for_each_trip(tz, trip) {
bool low_set = false;
int trip_low;
trip_low = trip->temperature - trip->hysteresis;
if (trip_low < tz->temperature && trip_low > low) {
low = trip_low;
low_set = true;
same_trip = false;
}
if (trip->temperature > tz->temperature &&
trip->temperature < high) {
high = trip->temperature;
same_trip = low_set;
}
}
/* No need to change trip points */
if (tz->prev_low_trip == low && tz->prev_high_trip == high)
return;
/*
* If "high" and "low" are the same, skip the change unless this is the
* first time.
*/
if (same_trip && (tz->prev_low_trip != -INT_MAX ||
tz->prev_high_trip != INT_MAX))
return;
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);
}
int __thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id,
struct thermal_trip *trip)
{
if (!tz || !tz->trips || trip_id < 0 || trip_id >= tz->num_trips || !trip)
return -EINVAL;
*trip = tz->trips[trip_id];
return 0;
}
EXPORT_SYMBOL_GPL(__thermal_zone_get_trip);
int thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id,
struct thermal_trip *trip)
{
int ret;
mutex_lock(&tz->lock);
ret = __thermal_zone_get_trip(tz, trip_id, trip);
mutex_unlock(&tz->lock);
return ret;
}
EXPORT_SYMBOL_GPL(thermal_zone_get_trip);
int thermal_zone_trip_id(const struct thermal_zone_device *tz,
const struct thermal_trip *trip)
{
/*
* Assume the trip to be located within the bounds of the thermal
* zone's trips[] table.
*/
return trip - tz->trips;
}
void thermal_zone_trip_updated(struct thermal_zone_device *tz,
const struct thermal_trip *trip)
{
thermal_notify_tz_trip_change(tz, trip);
__thermal_zone_device_update(tz, THERMAL_TRIP_CHANGED);
}
void thermal_zone_set_trip_temp(struct thermal_zone_device *tz,
struct thermal_trip *trip, int temp)
{
if (trip->temperature == temp)
return;
trip->temperature = temp;
thermal_notify_tz_trip_change(tz, trip);
}
EXPORT_SYMBOL_GPL(thermal_zone_set_trip_temp);