diff options
Diffstat (limited to 'drivers/thermal/thermal_trip.c')
| -rw-r--r-- | drivers/thermal/thermal_trip.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/drivers/thermal/thermal_trip.c b/drivers/thermal/thermal_trip.c new file mode 100644 index 000000000000..907f3a4d7bc8 --- /dev/null +++ b/drivers/thermal/thermal_trip.c @@ -0,0 +1,182 @@ +// 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) +{ + int i, ret; + struct thermal_trip trip; + + lockdep_assert_held(&tz->lock); + + for (i = 0; i < tz->num_trips; i++) { + + ret = __thermal_zone_get_trip(tz, i, &trip); + if (ret) + return ret; + + ret = cb(&trip, data); + if (ret) + return ret; + } + + return 0; +} + +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) +{ + struct thermal_trip trip; + int low = -INT_MAX, high = INT_MAX; + int i, ret; + + lockdep_assert_held(&tz->lock); + + if (!tz->ops->set_trips) + return; + + for (i = 0; i < tz->num_trips; i++) { + int trip_low; + + ret = __thermal_zone_get_trip(tz, i , &trip); + if (ret) + return; + + trip_low = trip.temperature - trip.hysteresis; + + if (trip_low < tz->temperature && trip_low > low) + low = trip_low; + + if (trip.temperature > tz->temperature && + trip.temperature < high) + high = trip.temperature; + } + + /* No need to change trip points */ + if (tz->prev_low_trip == low && tz->prev_high_trip == high) + 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) +{ + int ret; + + if (!tz || trip_id < 0 || trip_id >= tz->num_trips || !trip) + return -EINVAL; + + if (tz->trips) { + *trip = tz->trips[trip_id]; + return 0; + } + + if (tz->ops->get_trip_hyst) { + ret = tz->ops->get_trip_hyst(tz, trip_id, &trip->hysteresis); + if (ret) + return ret; + } else { + trip->hysteresis = 0; + } + + ret = tz->ops->get_trip_temp(tz, trip_id, &trip->temperature); + if (ret) + return ret; + + return tz->ops->get_trip_type(tz, trip_id, &trip->type); +} +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_set_trip(struct thermal_zone_device *tz, int trip_id, + const struct thermal_trip *trip) +{ + struct thermal_trip t; + int ret; + + if (!tz->ops->set_trip_temp && !tz->ops->set_trip_hyst && !tz->trips) + return -EINVAL; + + ret = __thermal_zone_get_trip(tz, trip_id, &t); + if (ret) + return ret; + + if (t.type != trip->type) + return -EINVAL; + + if (t.temperature != trip->temperature && tz->ops->set_trip_temp) { + ret = tz->ops->set_trip_temp(tz, trip_id, trip->temperature); + if (ret) + return ret; + } + + if (t.hysteresis != trip->hysteresis && tz->ops->set_trip_hyst) { + ret = tz->ops->set_trip_hyst(tz, trip_id, trip->hysteresis); + if (ret) + return ret; + } + + if (tz->trips && (t.temperature != trip->temperature || t.hysteresis != trip->hysteresis)) + tz->trips[trip_id] = *trip; + + thermal_notify_tz_trip_change(tz->id, trip_id, trip->type, + trip->temperature, trip->hysteresis); + + __thermal_zone_device_update(tz, THERMAL_TRIP_CHANGED); + + return 0; +} |