1 /* 2 * OMAP thermal driver interface 3 * 4 * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/ 5 * Contact: 6 * Eduardo Valentin <eduardo.valentin@ti.com> 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License 10 * version 2 as published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope that it will be useful, but 13 * WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 20 * 02110-1301 USA 21 * 22 */ 23 24 #include <linux/device.h> 25 #include <linux/err.h> 26 #include <linux/mutex.h> 27 #include <linux/gfp.h> 28 #include <linux/kernel.h> 29 #include <linux/workqueue.h> 30 #include <linux/thermal.h> 31 #include <linux/cpufreq.h> 32 #include <linux/cpumask.h> 33 #include <linux/cpu_cooling.h> 34 35 #include "ti-thermal.h" 36 #include "ti-bandgap.h" 37 38 /* common data structures */ 39 struct ti_thermal_data { 40 struct thermal_zone_device *ti_thermal; 41 struct thermal_zone_device *pcb_tz; 42 struct thermal_cooling_device *cool_dev; 43 struct ti_bandgap *bgp; 44 enum thermal_device_mode mode; 45 struct work_struct thermal_wq; 46 int sensor_id; 47 }; 48 49 static void ti_thermal_work(struct work_struct *work) 50 { 51 struct ti_thermal_data *data = container_of(work, 52 struct ti_thermal_data, thermal_wq); 53 54 thermal_zone_device_update(data->ti_thermal); 55 56 dev_dbg(&data->ti_thermal->device, "updated thermal zone %s\n", 57 data->ti_thermal->type); 58 } 59 60 /** 61 * ti_thermal_hotspot_temperature - returns sensor extrapolated temperature 62 * @t: omap sensor temperature 63 * @s: omap sensor slope value 64 * @c: omap sensor const value 65 */ 66 static inline int ti_thermal_hotspot_temperature(int t, int s, int c) 67 { 68 int delta = t * s / 1000 + c; 69 70 if (delta < 0) 71 delta = 0; 72 73 return t + delta; 74 } 75 76 /* thermal zone ops */ 77 /* Get temperature callback function for thermal zone*/ 78 static inline int ti_thermal_get_temp(struct thermal_zone_device *thermal, 79 unsigned long *temp) 80 { 81 struct thermal_zone_device *pcb_tz = NULL; 82 struct ti_thermal_data *data = thermal->devdata; 83 struct ti_bandgap *bgp; 84 const struct ti_temp_sensor *s; 85 int ret, tmp, slope, constant; 86 unsigned long pcb_temp; 87 88 if (!data) 89 return 0; 90 91 bgp = data->bgp; 92 s = &bgp->conf->sensors[data->sensor_id]; 93 94 ret = ti_bandgap_read_temperature(bgp, data->sensor_id, &tmp); 95 if (ret) 96 return ret; 97 98 /* Default constants */ 99 slope = s->slope; 100 constant = s->constant; 101 102 pcb_tz = data->pcb_tz; 103 /* In case pcb zone is available, use the extrapolation rule with it */ 104 if (!IS_ERR(pcb_tz)) { 105 ret = thermal_zone_get_temp(pcb_tz, &pcb_temp); 106 if (!ret) { 107 tmp -= pcb_temp; /* got a valid PCB temp */ 108 slope = s->slope_pcb; 109 constant = s->constant_pcb; 110 } else { 111 dev_err(bgp->dev, 112 "Failed to read PCB state. Using defaults\n"); 113 } 114 } 115 *temp = ti_thermal_hotspot_temperature(tmp, slope, constant); 116 117 return ret; 118 } 119 120 /* Bind callback functions for thermal zone */ 121 static int ti_thermal_bind(struct thermal_zone_device *thermal, 122 struct thermal_cooling_device *cdev) 123 { 124 struct ti_thermal_data *data = thermal->devdata; 125 int id; 126 127 if (!data || IS_ERR(data)) 128 return -ENODEV; 129 130 /* check if this is the cooling device we registered */ 131 if (data->cool_dev != cdev) 132 return 0; 133 134 id = data->sensor_id; 135 136 /* Simple thing, two trips, one passive another critical */ 137 return thermal_zone_bind_cooling_device(thermal, 0, cdev, 138 /* bind with min and max states defined by cpu_cooling */ 139 THERMAL_NO_LIMIT, 140 THERMAL_NO_LIMIT); 141 } 142 143 /* Unbind callback functions for thermal zone */ 144 static int ti_thermal_unbind(struct thermal_zone_device *thermal, 145 struct thermal_cooling_device *cdev) 146 { 147 struct ti_thermal_data *data = thermal->devdata; 148 149 if (!data || IS_ERR(data)) 150 return -ENODEV; 151 152 /* check if this is the cooling device we registered */ 153 if (data->cool_dev != cdev) 154 return 0; 155 156 /* Simple thing, two trips, one passive another critical */ 157 return thermal_zone_unbind_cooling_device(thermal, 0, cdev); 158 } 159 160 /* Get mode callback functions for thermal zone */ 161 static int ti_thermal_get_mode(struct thermal_zone_device *thermal, 162 enum thermal_device_mode *mode) 163 { 164 struct ti_thermal_data *data = thermal->devdata; 165 166 if (data) 167 *mode = data->mode; 168 169 return 0; 170 } 171 172 /* Set mode callback functions for thermal zone */ 173 static int ti_thermal_set_mode(struct thermal_zone_device *thermal, 174 enum thermal_device_mode mode) 175 { 176 struct ti_thermal_data *data = thermal->devdata; 177 struct ti_bandgap *bgp; 178 179 bgp = data->bgp; 180 181 if (!data->ti_thermal) { 182 dev_notice(&thermal->device, "thermal zone not registered\n"); 183 return 0; 184 } 185 186 mutex_lock(&data->ti_thermal->lock); 187 188 if (mode == THERMAL_DEVICE_ENABLED) 189 data->ti_thermal->polling_delay = FAST_TEMP_MONITORING_RATE; 190 else 191 data->ti_thermal->polling_delay = 0; 192 193 mutex_unlock(&data->ti_thermal->lock); 194 195 data->mode = mode; 196 ti_bandgap_write_update_interval(bgp, data->sensor_id, 197 data->ti_thermal->polling_delay); 198 thermal_zone_device_update(data->ti_thermal); 199 dev_dbg(&thermal->device, "thermal polling set for duration=%d msec\n", 200 data->ti_thermal->polling_delay); 201 202 return 0; 203 } 204 205 /* Get trip type callback functions for thermal zone */ 206 static int ti_thermal_get_trip_type(struct thermal_zone_device *thermal, 207 int trip, enum thermal_trip_type *type) 208 { 209 if (!ti_thermal_is_valid_trip(trip)) 210 return -EINVAL; 211 212 if (trip + 1 == OMAP_TRIP_NUMBER) 213 *type = THERMAL_TRIP_CRITICAL; 214 else 215 *type = THERMAL_TRIP_PASSIVE; 216 217 return 0; 218 } 219 220 /* Get trip temperature callback functions for thermal zone */ 221 static int ti_thermal_get_trip_temp(struct thermal_zone_device *thermal, 222 int trip, unsigned long *temp) 223 { 224 if (!ti_thermal_is_valid_trip(trip)) 225 return -EINVAL; 226 227 *temp = ti_thermal_get_trip_value(trip); 228 229 return 0; 230 } 231 232 /* Get the temperature trend callback functions for thermal zone */ 233 static int ti_thermal_get_trend(struct thermal_zone_device *thermal, 234 int trip, enum thermal_trend *trend) 235 { 236 struct ti_thermal_data *data = thermal->devdata; 237 struct ti_bandgap *bgp; 238 int id, tr, ret = 0; 239 240 bgp = data->bgp; 241 id = data->sensor_id; 242 243 ret = ti_bandgap_get_trend(bgp, id, &tr); 244 if (ret) 245 return ret; 246 247 if (tr > 0) 248 *trend = THERMAL_TREND_RAISING; 249 else if (tr < 0) 250 *trend = THERMAL_TREND_DROPPING; 251 else 252 *trend = THERMAL_TREND_STABLE; 253 254 return 0; 255 } 256 257 /* Get critical temperature callback functions for thermal zone */ 258 static int ti_thermal_get_crit_temp(struct thermal_zone_device *thermal, 259 unsigned long *temp) 260 { 261 /* shutdown zone */ 262 return ti_thermal_get_trip_temp(thermal, OMAP_TRIP_NUMBER - 1, temp); 263 } 264 265 static struct thermal_zone_device_ops ti_thermal_ops = { 266 .get_temp = ti_thermal_get_temp, 267 .get_trend = ti_thermal_get_trend, 268 .bind = ti_thermal_bind, 269 .unbind = ti_thermal_unbind, 270 .get_mode = ti_thermal_get_mode, 271 .set_mode = ti_thermal_set_mode, 272 .get_trip_type = ti_thermal_get_trip_type, 273 .get_trip_temp = ti_thermal_get_trip_temp, 274 .get_crit_temp = ti_thermal_get_crit_temp, 275 }; 276 277 static struct ti_thermal_data 278 *ti_thermal_build_data(struct ti_bandgap *bgp, int id) 279 { 280 struct ti_thermal_data *data; 281 282 data = devm_kzalloc(bgp->dev, sizeof(*data), GFP_KERNEL); 283 if (!data) { 284 dev_err(bgp->dev, "kzalloc fail\n"); 285 return NULL; 286 } 287 data->sensor_id = id; 288 data->bgp = bgp; 289 data->mode = THERMAL_DEVICE_ENABLED; 290 /* pcb_tz will be either valid or PTR_ERR() */ 291 data->pcb_tz = thermal_zone_get_zone_by_name("pcb"); 292 INIT_WORK(&data->thermal_wq, ti_thermal_work); 293 294 return data; 295 } 296 297 int ti_thermal_expose_sensor(struct ti_bandgap *bgp, int id, 298 char *domain) 299 { 300 struct ti_thermal_data *data; 301 302 data = ti_bandgap_get_sensor_data(bgp, id); 303 304 if (!data || IS_ERR(data)) 305 data = ti_thermal_build_data(bgp, id); 306 307 if (!data) 308 return -EINVAL; 309 310 /* Create thermal zone */ 311 data->ti_thermal = thermal_zone_device_register(domain, 312 OMAP_TRIP_NUMBER, 0, data, &ti_thermal_ops, 313 NULL, FAST_TEMP_MONITORING_RATE, 314 FAST_TEMP_MONITORING_RATE); 315 if (IS_ERR(data->ti_thermal)) { 316 dev_err(bgp->dev, "thermal zone device is NULL\n"); 317 return PTR_ERR(data->ti_thermal); 318 } 319 data->ti_thermal->polling_delay = FAST_TEMP_MONITORING_RATE; 320 ti_bandgap_set_sensor_data(bgp, id, data); 321 ti_bandgap_write_update_interval(bgp, data->sensor_id, 322 data->ti_thermal->polling_delay); 323 324 return 0; 325 } 326 327 int ti_thermal_remove_sensor(struct ti_bandgap *bgp, int id) 328 { 329 struct ti_thermal_data *data; 330 331 data = ti_bandgap_get_sensor_data(bgp, id); 332 333 thermal_zone_device_unregister(data->ti_thermal); 334 335 return 0; 336 } 337 338 int ti_thermal_report_sensor_temperature(struct ti_bandgap *bgp, int id) 339 { 340 struct ti_thermal_data *data; 341 342 data = ti_bandgap_get_sensor_data(bgp, id); 343 344 schedule_work(&data->thermal_wq); 345 346 return 0; 347 } 348 349 int ti_thermal_register_cpu_cooling(struct ti_bandgap *bgp, int id) 350 { 351 struct ti_thermal_data *data; 352 353 data = ti_bandgap_get_sensor_data(bgp, id); 354 if (!data || IS_ERR(data)) 355 data = ti_thermal_build_data(bgp, id); 356 357 if (!data) 358 return -EINVAL; 359 360 if (!cpufreq_get_current_driver()) { 361 dev_dbg(bgp->dev, "no cpufreq driver yet\n"); 362 return -EPROBE_DEFER; 363 } 364 365 /* Register cooling device */ 366 data->cool_dev = cpufreq_cooling_register(cpu_present_mask); 367 if (IS_ERR(data->cool_dev)) { 368 dev_err(bgp->dev, 369 "Failed to register cpufreq cooling device\n"); 370 return PTR_ERR(data->cool_dev); 371 } 372 ti_bandgap_set_sensor_data(bgp, id, data); 373 374 return 0; 375 } 376 377 int ti_thermal_unregister_cpu_cooling(struct ti_bandgap *bgp, int id) 378 { 379 struct ti_thermal_data *data; 380 381 data = ti_bandgap_get_sensor_data(bgp, id); 382 cpufreq_cooling_unregister(data->cool_dev); 383 384 return 0; 385 } 386