drivers/thermal/db8500_thermal.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * db8500_thermal.c - DB8500 Thermal Management Implementation
   4  *
   5  * Copyright (C) 2012 ST-Ericsson
   6  * Copyright (C) 2012 Linaro Ltd.
   7  *
   8  * Author: Hongbo Zhang <hongbo.zhang@linaro.com>
   9  */
  10
  11 #include <linux/cpu_cooling.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/mfd/dbx500-prcmu.h>
  14 #include <linux/module.h>
  15 #include <linux/of.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/slab.h>
  18 #include <linux/thermal.h>
  19
  20 #define PRCMU_DEFAULT_MEASURE_TIME      0xFFF
  21 #define PRCMU_DEFAULT_LOW_TEMP          0
  22 #define COOLING_DEV_MAX 8
  23
  24 struct db8500_trip_point {
  25         unsigned long temp;
  26         enum thermal_trip_type type;
  27         char cdev_name[COOLING_DEV_MAX][THERMAL_NAME_LENGTH];
  28 };
  29
  30 struct db8500_thsens_platform_data {
  31         struct db8500_trip_point trip_points[THERMAL_MAX_TRIPS];
  32         int num_trips;
  33 };
  34
  35 struct db8500_thermal_zone {
  36         struct thermal_zone_device *therm_dev;
  37         struct mutex th_lock;
  38         struct work_struct therm_work;
  39         struct db8500_thsens_platform_data *trip_tab;
  40         enum thermal_device_mode mode;
  41         enum thermal_trend trend;
  42         unsigned long cur_temp_pseudo;
  43         unsigned int cur_index;
  44 };
  45
  46 /* Local function to check if thermal zone matches cooling devices */
  47 static int db8500_thermal_match_cdev(struct thermal_cooling_device *cdev,
  48                 struct db8500_trip_point *trip_point)
  49 {
  50         int i;
  51
  52         if (!strlen(cdev->type))
  53                 return -EINVAL;
  54
  55         for (i = 0; i < COOLING_DEV_MAX; i++) {
  56                 if (!strcmp(trip_point->cdev_name[i], cdev->type))
  57                         return 0;
  58         }
  59
  60         return -ENODEV;
  61 }
  62
  63 /* Callback to bind cooling device to thermal zone */
  64 static int db8500_cdev_bind(struct thermal_zone_device *thermal,
  65                 struct thermal_cooling_device *cdev)
  66 {
  67         struct db8500_thermal_zone *pzone = thermal->devdata;
  68         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
  69         unsigned long max_state, upper, lower;
  70         int i, ret = -EINVAL;
  71
  72         cdev->ops->get_max_state(cdev, &max_state);
  73
  74         for (i = 0; i < ptrips->num_trips; i++) {
  75                 if (db8500_thermal_match_cdev(cdev, &ptrips->trip_points[i]))
  76                         continue;
  77
  78                 upper = lower = i > max_state ? max_state : i;
  79
  80                 ret = thermal_zone_bind_cooling_device(thermal, i, cdev,
  81                         upper, lower, THERMAL_WEIGHT_DEFAULT);
  82
  83                 dev_info(&cdev->device, "%s bind to %d: %d-%s\n", cdev->type,
  84                         i, ret, ret ? "fail" : "succeed");
  85         }
  86
  87         return ret;
  88 }
  89
  90 /* Callback to unbind cooling device from thermal zone */
  91 static int db8500_cdev_unbind(struct thermal_zone_device *thermal,
  92                 struct thermal_cooling_device *cdev)
  93 {
  94         struct db8500_thermal_zone *pzone = thermal->devdata;
  95         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
  96         int i, ret = -EINVAL;
  97
  98         for (i = 0; i < ptrips->num_trips; i++) {
  99                 if (db8500_thermal_match_cdev(cdev, &ptrips->trip_points[i]))
 100                         continue;
 101
 102                 ret = thermal_zone_unbind_cooling_device(thermal, i, cdev);
 103
 104                 dev_info(&cdev->device, "%s unbind from %d: %s\n", cdev->type,
 105                         i, ret ? "fail" : "succeed");
 106         }
 107
 108         return ret;
 109 }
 110
 111 /* Callback to get current temperature */
 112 static int db8500_sys_get_temp(struct thermal_zone_device *thermal, int *temp)
 113 {
 114         struct db8500_thermal_zone *pzone = thermal->devdata;
 115
 116         /*
 117          * TODO: There is no PRCMU interface to get temperature data currently,
 118          * so a pseudo temperature is returned , it works for thermal framework
 119          * and this will be fixed when the PRCMU interface is available.
 120          */
 121         *temp = pzone->cur_temp_pseudo;
 122
 123         return 0;
 124 }
 125
 126 /* Callback to get temperature changing trend */
 127 static int db8500_sys_get_trend(struct thermal_zone_device *thermal,
 128                 int trip, enum thermal_trend *trend)
 129 {
 130         struct db8500_thermal_zone *pzone = thermal->devdata;
 131
 132         *trend = pzone->trend;
 133
 134         return 0;
 135 }
 136
 137 /* Callback to get thermal zone mode */
 138 static int db8500_sys_get_mode(struct thermal_zone_device *thermal,
 139                 enum thermal_device_mode *mode)
 140 {
 141         struct db8500_thermal_zone *pzone = thermal->devdata;
 142
 143         mutex_lock(&pzone->th_lock);
 144         *mode = pzone->mode;
 145         mutex_unlock(&pzone->th_lock);
 146
 147         return 0;
 148 }
 149
 150 /* Callback to set thermal zone mode */
 151 static int db8500_sys_set_mode(struct thermal_zone_device *thermal,
 152                 enum thermal_device_mode mode)
 153 {
 154         struct db8500_thermal_zone *pzone = thermal->devdata;
 155
 156         mutex_lock(&pzone->th_lock);
 157
 158         pzone->mode = mode;
 159         if (mode == THERMAL_DEVICE_ENABLED)
 160                 schedule_work(&pzone->therm_work);
 161
 162         mutex_unlock(&pzone->th_lock);
 163
 164         return 0;
 165 }
 166
 167 /* Callback to get trip point type */
 168 static int db8500_sys_get_trip_type(struct thermal_zone_device *thermal,
 169                 int trip, enum thermal_trip_type *type)
 170 {
 171         struct db8500_thermal_zone *pzone = thermal->devdata;
 172         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 173
 174         if (trip >= ptrips->num_trips)
 175                 return -EINVAL;
 176
 177         *type = ptrips->trip_points[trip].type;
 178
 179         return 0;
 180 }
 181
 182 /* Callback to get trip point temperature */
 183 static int db8500_sys_get_trip_temp(struct thermal_zone_device *thermal,
 184                 int trip, int *temp)
 185 {
 186         struct db8500_thermal_zone *pzone = thermal->devdata;
 187         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 188
 189         if (trip >= ptrips->num_trips)
 190                 return -EINVAL;
 191
 192         *temp = ptrips->trip_points[trip].temp;
 193
 194         return 0;
 195 }
 196
 197 /* Callback to get critical trip point temperature */
 198 static int db8500_sys_get_crit_temp(struct thermal_zone_device *thermal,
 199                 int *temp)
 200 {
 201         struct db8500_thermal_zone *pzone = thermal->devdata;
 202         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 203         int i;
 204
 205         for (i = ptrips->num_trips - 1; i > 0; i--) {
 206                 if (ptrips->trip_points[i].type == THERMAL_TRIP_CRITICAL) {
 207                         *temp = ptrips->trip_points[i].temp;
 208                         return 0;
 209                 }
 210         }
 211
 212         return -EINVAL;
 213 }
 214
 215 static struct thermal_zone_device_ops thdev_ops = {
 216         .bind = db8500_cdev_bind,
 217         .unbind = db8500_cdev_unbind,
 218         .get_temp = db8500_sys_get_temp,
 219         .get_trend = db8500_sys_get_trend,
 220         .get_mode = db8500_sys_get_mode,
 221         .set_mode = db8500_sys_set_mode,
 222         .get_trip_type = db8500_sys_get_trip_type,
 223         .get_trip_temp = db8500_sys_get_trip_temp,
 224         .get_crit_temp = db8500_sys_get_crit_temp,
 225 };
 226
 227 static void db8500_thermal_update_config(struct db8500_thermal_zone *pzone,
 228                 unsigned int idx, enum thermal_trend trend,
 229                 unsigned long next_low, unsigned long next_high)
 230 {
 231         prcmu_stop_temp_sense();
 232
 233         pzone->cur_index = idx;
 234         pzone->cur_temp_pseudo = (next_low + next_high)/2;
 235         pzone->trend = trend;
 236
 237         prcmu_config_hotmon((u8)(next_low/1000), (u8)(next_high/1000));
 238         prcmu_start_temp_sense(PRCMU_DEFAULT_MEASURE_TIME);
 239 }
 240
 241 static irqreturn_t prcmu_low_irq_handler(int irq, void *irq_data)
 242 {
 243         struct db8500_thermal_zone *pzone = irq_data;
 244         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 245         unsigned int idx = pzone->cur_index;
 246         unsigned long next_low, next_high;
 247
 248         if (unlikely(idx == 0))
 249                 /* Meaningless for thermal management, ignoring it */
 250                 return IRQ_HANDLED;
 251
 252         if (idx == 1) {
 253                 next_high = ptrips->trip_points[0].temp;
 254                 next_low = PRCMU_DEFAULT_LOW_TEMP;
 255         } else {
 256                 next_high = ptrips->trip_points[idx-1].temp;
 257                 next_low = ptrips->trip_points[idx-2].temp;
 258         }
 259         idx -= 1;
 260
 261         db8500_thermal_update_config(pzone, idx, THERMAL_TREND_DROPPING,
 262                 next_low, next_high);
 263
 264         dev_dbg(&pzone->therm_dev->device,
 265                 "PRCMU set max %ld, min %ld\n", next_high, next_low);
 266
 267         schedule_work(&pzone->therm_work);
 268
 269         return IRQ_HANDLED;
 270 }
 271
 272 static irqreturn_t prcmu_high_irq_handler(int irq, void *irq_data)
 273 {
 274         struct db8500_thermal_zone *pzone = irq_data;
 275         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 276         unsigned int idx = pzone->cur_index;
 277         unsigned long next_low, next_high;
 278
 279         if (idx < ptrips->num_trips - 1) {
 280                 next_high = ptrips->trip_points[idx+1].temp;
 281                 next_low = ptrips->trip_points[idx].temp;
 282                 idx += 1;
 283
 284                 db8500_thermal_update_config(pzone, idx, THERMAL_TREND_RAISING,
 285                         next_low, next_high);
 286
 287                 dev_dbg(&pzone->therm_dev->device,
 288                 "PRCMU set max %ld, min %ld\n", next_high, next_low);
 289         } else if (idx == ptrips->num_trips - 1)
 290                 pzone->cur_temp_pseudo = ptrips->trip_points[idx].temp + 1;
 291
 292         schedule_work(&pzone->therm_work);
 293
 294         return IRQ_HANDLED;
 295 }
 296
 297 static void db8500_thermal_work(struct work_struct *work)
 298 {
 299         enum thermal_device_mode cur_mode;
 300         struct db8500_thermal_zone *pzone;
 301
 302         pzone = container_of(work, struct db8500_thermal_zone, therm_work);
 303
 304         mutex_lock(&pzone->th_lock);
 305         cur_mode = pzone->mode;
 306         mutex_unlock(&pzone->th_lock);
 307
 308         if (cur_mode == THERMAL_DEVICE_DISABLED)
 309                 return;
 310
 311         thermal_zone_device_update(pzone->therm_dev, THERMAL_EVENT_UNSPECIFIED);
 312         dev_dbg(&pzone->therm_dev->device, "thermal work finished.\n");
 313 }
 314
 315 static struct db8500_thsens_platform_data*
 316                 db8500_thermal_parse_dt(struct platform_device *pdev)
 317 {
 318         struct db8500_thsens_platform_data *ptrips;
 319         struct device_node *np = pdev->dev.of_node;
 320         char prop_name[32];
 321         const char *tmp_str;
 322         u32 tmp_data;
 323         int i, j;
 324
 325         ptrips = devm_kzalloc(&pdev->dev, sizeof(*ptrips), GFP_KERNEL);
 326         if (!ptrips)
 327                 return NULL;
 328
 329         if (of_property_read_u32(np, "num-trips", &tmp_data))
 330                 goto err_parse_dt;
 331
 332         if (tmp_data > THERMAL_MAX_TRIPS)
 333                 goto err_parse_dt;
 334
 335         ptrips->num_trips = tmp_data;
 336
 337         for (i = 0; i < ptrips->num_trips; i++) {
 338                 sprintf(prop_name, "trip%d-temp", i);
 339                 if (of_property_read_u32(np, prop_name, &tmp_data))
 340                         goto err_parse_dt;
 341
 342                 ptrips->trip_points[i].temp = tmp_data;
 343
 344                 sprintf(prop_name, "trip%d-type", i);
 345                 if (of_property_read_string(np, prop_name, &tmp_str))
 346                         goto err_parse_dt;
 347
 348                 if (!strcmp(tmp_str, "active"))
 349                         ptrips->trip_points[i].type = THERMAL_TRIP_ACTIVE;
 350                 else if (!strcmp(tmp_str, "passive"))
 351                         ptrips->trip_points[i].type = THERMAL_TRIP_PASSIVE;
 352                 else if (!strcmp(tmp_str, "hot"))
 353                         ptrips->trip_points[i].type = THERMAL_TRIP_HOT;
 354                 else if (!strcmp(tmp_str, "critical"))
 355                         ptrips->trip_points[i].type = THERMAL_TRIP_CRITICAL;
 356                 else
 357                         goto err_parse_dt;
 358
 359                 sprintf(prop_name, "trip%d-cdev-num", i);
 360                 if (of_property_read_u32(np, prop_name, &tmp_data))
 361                         goto err_parse_dt;
 362
 363                 if (tmp_data > COOLING_DEV_MAX)
 364                         goto err_parse_dt;
 365
 366                 for (j = 0; j < tmp_data; j++) {
 367                         sprintf(prop_name, "trip%d-cdev-name%d", i, j);
 368                         if (of_property_read_string(np, prop_name, &tmp_str))
 369                                 goto err_parse_dt;
 370
 371                         if (strlen(tmp_str) >= THERMAL_NAME_LENGTH)
 372                                 goto err_parse_dt;
 373
 374                         strcpy(ptrips->trip_points[i].cdev_name[j], tmp_str);
 375                 }
 376         }
 377         return ptrips;
 378
 379 err_parse_dt:
 380         dev_err(&pdev->dev, "Parsing device tree data error.\n");
 381         return NULL;
 382 }
 383
 384 static int db8500_thermal_probe(struct platform_device *pdev)
 385 {
 386         struct db8500_thermal_zone *pzone = NULL;
 387         struct db8500_thsens_platform_data *ptrips = NULL;
 388         struct device_node *np = pdev->dev.of_node;
 389         int low_irq, high_irq, ret = 0;
 390         unsigned long dft_low, dft_high;
 391
 392         if (!np)
 393                 return -EINVAL;
 394
 395         ptrips = db8500_thermal_parse_dt(pdev);
 396         if (!ptrips)
 397                 return -EINVAL;
 398
 399         pzone = devm_kzalloc(&pdev->dev, sizeof(*pzone), GFP_KERNEL);
 400         if (!pzone)
 401                 return -ENOMEM;
 402
 403         mutex_init(&pzone->th_lock);
 404         mutex_lock(&pzone->th_lock);
 405
 406         pzone->mode = THERMAL_DEVICE_DISABLED;
 407         pzone->trip_tab = ptrips;
 408
 409         INIT_WORK(&pzone->therm_work, db8500_thermal_work);
 410
 411         low_irq = platform_get_irq_byname(pdev, "IRQ_HOTMON_LOW");
 412         if (low_irq < 0) {
 413                 dev_err(&pdev->dev, "Get IRQ_HOTMON_LOW failed.\n");
 414                 ret = low_irq;
 415                 goto out_unlock;
 416         }
 417
 418         ret = devm_request_threaded_irq(&pdev->dev, low_irq, NULL,
 419                 prcmu_low_irq_handler, IRQF_NO_SUSPEND | IRQF_ONESHOT,
 420                 "dbx500_temp_low", pzone);
 421         if (ret < 0) {
 422                 dev_err(&pdev->dev, "Failed to allocate temp low irq.\n");
 423                 goto out_unlock;
 424         }
 425
 426         high_irq = platform_get_irq_byname(pdev, "IRQ_HOTMON_HIGH");
 427         if (high_irq < 0) {
 428                 dev_err(&pdev->dev, "Get IRQ_HOTMON_HIGH failed.\n");
 429                 ret = high_irq;
 430                 goto out_unlock;
 431         }
 432
 433         ret = devm_request_threaded_irq(&pdev->dev, high_irq, NULL,
 434                 prcmu_high_irq_handler, IRQF_NO_SUSPEND | IRQF_ONESHOT,
 435                 "dbx500_temp_high", pzone);
 436         if (ret < 0) {
 437                 dev_err(&pdev->dev, "Failed to allocate temp high irq.\n");
 438                 goto out_unlock;
 439         }
 440
 441         pzone->therm_dev = thermal_zone_device_register("db8500_thermal_zone",
 442                 ptrips->num_trips, 0, pzone, &thdev_ops, NULL, 0, 0);
 443
 444         if (IS_ERR(pzone->therm_dev)) {
 445                 dev_err(&pdev->dev, "Register thermal zone device failed.\n");
 446                 ret = PTR_ERR(pzone->therm_dev);
 447                 goto out_unlock;
 448         }
 449         dev_info(&pdev->dev, "Thermal zone device registered.\n");
 450
 451         dft_low = PRCMU_DEFAULT_LOW_TEMP;
 452         dft_high = ptrips->trip_points[0].temp;
 453
 454         db8500_thermal_update_config(pzone, 0, THERMAL_TREND_STABLE,
 455                 dft_low, dft_high);
 456
 457         platform_set_drvdata(pdev, pzone);
 458         pzone->mode = THERMAL_DEVICE_ENABLED;
 459
 460 out_unlock:
 461         mutex_unlock(&pzone->th_lock);
 462
 463         return ret;
 464 }
 465
 466 static int db8500_thermal_remove(struct platform_device *pdev)
 467 {
 468         struct db8500_thermal_zone *pzone = platform_get_drvdata(pdev);
 469
 470         thermal_zone_device_unregister(pzone->therm_dev);
 471         cancel_work_sync(&pzone->therm_work);
 472         mutex_destroy(&pzone->th_lock);
 473
 474         return 0;
 475 }
 476
 477 static int db8500_thermal_suspend(struct platform_device *pdev,
 478                 pm_message_t state)
 479 {
 480         struct db8500_thermal_zone *pzone = platform_get_drvdata(pdev);
 481
 482         flush_work(&pzone->therm_work);
 483         prcmu_stop_temp_sense();
 484
 485         return 0;
 486 }
 487
 488 static int db8500_thermal_resume(struct platform_device *pdev)
 489 {
 490         struct db8500_thermal_zone *pzone = platform_get_drvdata(pdev);
 491         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 492         unsigned long dft_low, dft_high;
 493
 494         dft_low = PRCMU_DEFAULT_LOW_TEMP;
 495         dft_high = ptrips->trip_points[0].temp;
 496
 497         db8500_thermal_update_config(pzone, 0, THERMAL_TREND_STABLE,
 498                 dft_low, dft_high);
 499
 500         return 0;
 501 }
 502
 503 static const struct of_device_id db8500_thermal_match[] = {
 504         { .compatible = "stericsson,db8500-thermal" },
 505         {},
 506 };
 507 MODULE_DEVICE_TABLE(of, db8500_thermal_match);
 508
 509 static struct platform_driver db8500_thermal_driver = {
 510         .driver = {
 511                 .name = "db8500-thermal",
 512                 .of_match_table = of_match_ptr(db8500_thermal_match),
 513         },
 514         .probe = db8500_thermal_probe,
 515         .suspend = db8500_thermal_suspend,
 516         .resume = db8500_thermal_resume,
 517         .remove = db8500_thermal_remove,
 518 };
 519
 520 module_platform_driver(db8500_thermal_driver);
 521
 522 MODULE_AUTHOR("Hongbo Zhang <hongbo.zhang@stericsson.com>");
 523 MODULE_DESCRIPTION("DB8500 thermal driver");
 524 MODULE_LICENSE("GPL");