drivers/thermal/ti-soc-thermal/ti-thermal-common.c

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