1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * OMAP thermal driver interface 4 * 5 * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/ 6 * Contact: 7 * Eduardo Valentin <eduardo.valentin@ti.com> 8 */ 9 10 #include <linux/device.h> 11 #include <linux/err.h> 12 #include <linux/mutex.h> 13 #include <linux/gfp.h> 14 #include <linux/kernel.h> 15 #include <linux/workqueue.h> 16 #include <linux/thermal.h> 17 #include <linux/cpufreq.h> 18 #include <linux/cpumask.h> 19 #include <linux/cpu_cooling.h> 20 #include <linux/of.h> 21 22 #include "ti-thermal.h" 23 #include "ti-bandgap.h" 24 25 /* common data structures */ 26 struct ti_thermal_data { 27 struct cpufreq_policy *policy; 28 struct thermal_zone_device *ti_thermal; 29 struct thermal_zone_device *pcb_tz; 30 struct thermal_cooling_device *cool_dev; 31 struct ti_bandgap *bgp; 32 enum thermal_device_mode mode; 33 struct work_struct thermal_wq; 34 int sensor_id; 35 bool our_zone; 36 }; 37 38 static void ti_thermal_work(struct work_struct *work) 39 { 40 struct ti_thermal_data *data = container_of(work, 41 struct ti_thermal_data, thermal_wq); 42 43 thermal_zone_device_update(data->ti_thermal, THERMAL_EVENT_UNSPECIFIED); 44 45 dev_dbg(&data->ti_thermal->device, "updated thermal zone %s\n", 46 data->ti_thermal->type); 47 } 48 49 /** 50 * ti_thermal_hotspot_temperature - returns sensor extrapolated temperature 51 * @t: omap sensor temperature 52 * @s: omap sensor slope value 53 * @c: omap sensor const value 54 */ 55 static inline int ti_thermal_hotspot_temperature(int t, int s, int c) 56 { 57 int delta = t * s / 1000 + c; 58 59 if (delta < 0) 60 delta = 0; 61 62 return t + delta; 63 } 64 65 /* thermal zone ops */ 66 /* Get temperature callback function for thermal zone */ 67 static inline int __ti_thermal_get_temp(void *devdata, int *temp) 68 { 69 struct thermal_zone_device *pcb_tz = NULL; 70 struct ti_thermal_data *data = devdata; 71 struct ti_bandgap *bgp; 72 const struct ti_temp_sensor *s; 73 int ret, tmp, slope, constant; 74 int pcb_temp; 75 76 if (!data) 77 return 0; 78 79 bgp = data->bgp; 80 s = &bgp->conf->sensors[data->sensor_id]; 81 82 ret = ti_bandgap_read_temperature(bgp, data->sensor_id, &tmp); 83 if (ret) 84 return ret; 85 86 /* Default constants */ 87 slope = thermal_zone_get_slope(data->ti_thermal); 88 constant = thermal_zone_get_offset(data->ti_thermal); 89 90 pcb_tz = data->pcb_tz; 91 /* In case pcb zone is available, use the extrapolation rule with it */ 92 if (!IS_ERR(pcb_tz)) { 93 ret = thermal_zone_get_temp(pcb_tz, &pcb_temp); 94 if (!ret) { 95 tmp -= pcb_temp; /* got a valid PCB temp */ 96 slope = s->slope_pcb; 97 constant = s->constant_pcb; 98 } else { 99 dev_err(bgp->dev, 100 "Failed to read PCB state. Using defaults\n"); 101 ret = 0; 102 } 103 } 104 *temp = ti_thermal_hotspot_temperature(tmp, slope, constant); 105 106 return ret; 107 } 108 109 static inline int ti_thermal_get_temp(struct thermal_zone_device *thermal, 110 int *temp) 111 { 112 struct ti_thermal_data *data = thermal->devdata; 113 114 return __ti_thermal_get_temp(data, temp); 115 } 116 117 static int __ti_thermal_get_trend(void *p, int trip, enum thermal_trend *trend) 118 { 119 struct ti_thermal_data *data = p; 120 struct ti_bandgap *bgp; 121 int id, tr, ret = 0; 122 123 bgp = data->bgp; 124 id = data->sensor_id; 125 126 ret = ti_bandgap_get_trend(bgp, id, &tr); 127 if (ret) 128 return ret; 129 130 if (tr > 0) 131 *trend = THERMAL_TREND_RAISING; 132 else if (tr < 0) 133 *trend = THERMAL_TREND_DROPPING; 134 else 135 *trend = THERMAL_TREND_STABLE; 136 137 return 0; 138 } 139 140 static const struct thermal_zone_of_device_ops ti_of_thermal_ops = { 141 .get_temp = __ti_thermal_get_temp, 142 .get_trend = __ti_thermal_get_trend, 143 }; 144 145 static struct ti_thermal_data 146 *ti_thermal_build_data(struct ti_bandgap *bgp, int id) 147 { 148 struct ti_thermal_data *data; 149 150 data = devm_kzalloc(bgp->dev, sizeof(*data), GFP_KERNEL); 151 if (!data) { 152 dev_err(bgp->dev, "kzalloc fail\n"); 153 return NULL; 154 } 155 data->sensor_id = id; 156 data->bgp = bgp; 157 data->mode = THERMAL_DEVICE_ENABLED; 158 /* pcb_tz will be either valid or PTR_ERR() */ 159 data->pcb_tz = thermal_zone_get_zone_by_name("pcb"); 160 INIT_WORK(&data->thermal_wq, ti_thermal_work); 161 162 return data; 163 } 164 165 int ti_thermal_expose_sensor(struct ti_bandgap *bgp, int id, 166 char *domain) 167 { 168 struct ti_thermal_data *data; 169 170 data = ti_bandgap_get_sensor_data(bgp, id); 171 172 if (!data || IS_ERR(data)) 173 data = ti_thermal_build_data(bgp, id); 174 175 if (!data) 176 return -EINVAL; 177 178 /* in case this is specified by DT */ 179 data->ti_thermal = devm_thermal_zone_of_sensor_register(bgp->dev, id, 180 data, &ti_of_thermal_ops); 181 if (IS_ERR(data->ti_thermal)) { 182 dev_err(bgp->dev, "thermal zone device is NULL\n"); 183 return PTR_ERR(data->ti_thermal); 184 } 185 186 ti_bandgap_set_sensor_data(bgp, id, data); 187 ti_bandgap_write_update_interval(bgp, data->sensor_id, 188 data->ti_thermal->polling_delay); 189 190 return 0; 191 } 192 193 int ti_thermal_remove_sensor(struct ti_bandgap *bgp, int id) 194 { 195 struct ti_thermal_data *data; 196 197 data = ti_bandgap_get_sensor_data(bgp, id); 198 199 if (data && data->ti_thermal) { 200 if (data->our_zone) 201 thermal_zone_device_unregister(data->ti_thermal); 202 } 203 204 return 0; 205 } 206 207 int ti_thermal_report_sensor_temperature(struct ti_bandgap *bgp, int id) 208 { 209 struct ti_thermal_data *data; 210 211 data = ti_bandgap_get_sensor_data(bgp, id); 212 213 schedule_work(&data->thermal_wq); 214 215 return 0; 216 } 217 218 int ti_thermal_register_cpu_cooling(struct ti_bandgap *bgp, int id) 219 { 220 struct ti_thermal_data *data; 221 struct device_node *np = bgp->dev->of_node; 222 223 /* 224 * We are assuming here that if one deploys the zone 225 * using DT, then it must be aware that the cooling device 226 * loading has to happen via cpufreq driver. 227 */ 228 if (of_find_property(np, "#thermal-sensor-cells", NULL)) 229 return 0; 230 231 data = ti_bandgap_get_sensor_data(bgp, id); 232 if (!data || IS_ERR(data)) 233 data = ti_thermal_build_data(bgp, id); 234 235 if (!data) 236 return -EINVAL; 237 238 data->policy = cpufreq_cpu_get(0); 239 if (!data->policy) { 240 pr_debug("%s: CPUFreq policy not found\n", __func__); 241 return -EPROBE_DEFER; 242 } 243 244 /* Register cooling device */ 245 data->cool_dev = cpufreq_cooling_register(data->policy); 246 if (IS_ERR(data->cool_dev)) { 247 int ret = PTR_ERR(data->cool_dev); 248 dev_err(bgp->dev, "Failed to register cpu cooling device %d\n", 249 ret); 250 cpufreq_cpu_put(data->policy); 251 252 return ret; 253 } 254 ti_bandgap_set_sensor_data(bgp, id, data); 255 256 return 0; 257 } 258 259 int ti_thermal_unregister_cpu_cooling(struct ti_bandgap *bgp, int id) 260 { 261 struct ti_thermal_data *data; 262 263 data = ti_bandgap_get_sensor_data(bgp, id); 264 265 if (data) { 266 cpufreq_cooling_unregister(data->cool_dev); 267 if (data->policy) 268 cpufreq_cpu_put(data->policy); 269 } 270 271 return 0; 272 } 273