1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2008 Intel Corp 4 * Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com> 5 * Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com> 6 * Copyright 2022 Linaro Limited 7 * 8 * Thermal trips handling 9 */ 10 #include "thermal_core.h" 11 12 int for_each_thermal_trip(struct thermal_zone_device *tz, 13 int (*cb)(struct thermal_trip *, void *), 14 void *data) 15 { 16 struct thermal_trip *trip; 17 int ret; 18 19 for_each_trip(tz, trip) { 20 ret = cb(trip, data); 21 if (ret) 22 return ret; 23 } 24 25 return 0; 26 } 27 EXPORT_SYMBOL_GPL(for_each_thermal_trip); 28 29 int thermal_zone_for_each_trip(struct thermal_zone_device *tz, 30 int (*cb)(struct thermal_trip *, void *), 31 void *data) 32 { 33 int ret; 34 35 mutex_lock(&tz->lock); 36 ret = for_each_thermal_trip(tz, cb, data); 37 mutex_unlock(&tz->lock); 38 39 return ret; 40 } 41 EXPORT_SYMBOL_GPL(thermal_zone_for_each_trip); 42 43 int thermal_zone_get_num_trips(struct thermal_zone_device *tz) 44 { 45 return tz->num_trips; 46 } 47 EXPORT_SYMBOL_GPL(thermal_zone_get_num_trips); 48 49 /** 50 * __thermal_zone_set_trips - Computes the next trip points for the driver 51 * @tz: a pointer to a thermal zone device structure 52 * 53 * The function computes the next temperature boundaries by browsing 54 * the trip points. The result is the closer low and high trip points 55 * to the current temperature. These values are passed to the backend 56 * driver to let it set its own notification mechanism (usually an 57 * interrupt). 58 * 59 * This function must be called with tz->lock held. Both tz and tz->ops 60 * must be valid pointers. 61 * 62 * It does not return a value 63 */ 64 void __thermal_zone_set_trips(struct thermal_zone_device *tz) 65 { 66 const struct thermal_trip *trip; 67 int low = -INT_MAX, high = INT_MAX; 68 bool same_trip = false; 69 int ret; 70 71 lockdep_assert_held(&tz->lock); 72 73 if (!tz->ops->set_trips) 74 return; 75 76 for_each_trip(tz, trip) { 77 bool low_set = false; 78 int trip_low; 79 80 trip_low = trip->temperature - trip->hysteresis; 81 82 if (trip_low < tz->temperature && trip_low > low) { 83 low = trip_low; 84 low_set = true; 85 same_trip = false; 86 } 87 88 if (trip->temperature > tz->temperature && 89 trip->temperature < high) { 90 high = trip->temperature; 91 same_trip = low_set; 92 } 93 } 94 95 /* No need to change trip points */ 96 if (tz->prev_low_trip == low && tz->prev_high_trip == high) 97 return; 98 99 /* 100 * If "high" and "low" are the same, skip the change unless this is the 101 * first time. 102 */ 103 if (same_trip && (tz->prev_low_trip != -INT_MAX || 104 tz->prev_high_trip != INT_MAX)) 105 return; 106 107 tz->prev_low_trip = low; 108 tz->prev_high_trip = high; 109 110 dev_dbg(&tz->device, 111 "new temperature boundaries: %d < x < %d\n", low, high); 112 113 /* 114 * Set a temperature window. When this window is left the driver 115 * must inform the thermal core via thermal_zone_device_update. 116 */ 117 ret = tz->ops->set_trips(tz, low, high); 118 if (ret) 119 dev_err(&tz->device, "Failed to set trips: %d\n", ret); 120 } 121 122 int __thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id, 123 struct thermal_trip *trip) 124 { 125 if (!tz || !tz->trips || trip_id < 0 || trip_id >= tz->num_trips || !trip) 126 return -EINVAL; 127 128 *trip = tz->trips[trip_id]; 129 return 0; 130 } 131 EXPORT_SYMBOL_GPL(__thermal_zone_get_trip); 132 133 int thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id, 134 struct thermal_trip *trip) 135 { 136 int ret; 137 138 mutex_lock(&tz->lock); 139 ret = __thermal_zone_get_trip(tz, trip_id, trip); 140 mutex_unlock(&tz->lock); 141 142 return ret; 143 } 144 EXPORT_SYMBOL_GPL(thermal_zone_get_trip); 145 146 int thermal_zone_trip_id(const struct thermal_zone_device *tz, 147 const struct thermal_trip *trip) 148 { 149 /* 150 * Assume the trip to be located within the bounds of the thermal 151 * zone's trips[] table. 152 */ 153 return trip - tz->trips; 154 } 155 void thermal_zone_trip_updated(struct thermal_zone_device *tz, 156 const struct thermal_trip *trip) 157 { 158 thermal_notify_tz_trip_change(tz, trip); 159 __thermal_zone_device_update(tz, THERMAL_TRIP_CHANGED); 160 } 161 162 void thermal_zone_set_trip_temp(struct thermal_zone_device *tz, 163 struct thermal_trip *trip, int temp) 164 { 165 if (trip->temperature == temp) 166 return; 167 168 trip->temperature = temp; 169 thermal_notify_tz_trip_change(tz, trip); 170 } 171 EXPORT_SYMBOL_GPL(thermal_zone_set_trip_temp); 172