drivers/thermal/db8500_thermal.c

   1 /*
   2  * db8500_thermal.c - DB8500 Thermal Management Implementation
   3  *
   4  * Copyright (C) 2012 ST-Ericsson
   5  * Copyright (C) 2012 Linaro Ltd.
   6  *
   7  * Author: Hongbo Zhang <hongbo.zhang@linaro.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  */
  19
  20 #include <linux/cpu_cooling.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/mfd/dbx500-prcmu.h>
  23 #include <linux/module.h>
  24 #include <linux/of.h>
  25 #include <linux/platform_data/db8500_thermal.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/slab.h>
  28 #include <linux/thermal.h>
  29
  30 #define PRCMU_DEFAULT_MEASURE_TIME      0xFFF
  31 #define PRCMU_DEFAULT_LOW_TEMP          0
  32
  33 struct db8500_thermal_zone {
  34         struct thermal_zone_device *therm_dev;
  35         struct mutex th_lock;
  36         struct work_struct therm_work;
  37         struct db8500_thsens_platform_data *trip_tab;
  38         enum thermal_device_mode mode;
  39         enum thermal_trend trend;
  40         unsigned long cur_temp_pseudo;
  41         unsigned int cur_index;
  42 };
  43
  44 /* Local function to check if thermal zone matches cooling devices */
  45 static int db8500_thermal_match_cdev(struct thermal_cooling_device *cdev,
  46                 struct db8500_trip_point *trip_point)
  47 {
  48         int i;
  49
  50         if (!strlen(cdev->type))
  51                 return -EINVAL;
  52
  53         for (i = 0; i < COOLING_DEV_MAX; i++) {
  54                 if (!strcmp(trip_point->cdev_name[i], cdev->type))
  55                         return 0;
  56         }
  57
  58         return -ENODEV;
  59 }
  60
  61 /* Callback to bind cooling device to thermal zone */
  62 static int db8500_cdev_bind(struct thermal_zone_device *thermal,
  63                 struct thermal_cooling_device *cdev)
  64 {
  65         struct db8500_thermal_zone *pzone = thermal->devdata;
  66         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
  67         unsigned long max_state, upper, lower;
  68         int i, ret = -EINVAL;
  69
  70         cdev->ops->get_max_state(cdev, &max_state);
  71
  72         for (i = 0; i < ptrips->num_trips; i++) {
  73                 if (db8500_thermal_match_cdev(cdev, &ptrips->trip_points[i]))
  74                         continue;
  75
  76                 upper = lower = i > max_state ? max_state : i;
  77
  78                 ret = thermal_zone_bind_cooling_device(thermal, i, cdev,
  79                         upper, lower, THERMAL_WEIGHT_DEFAULT);
  80
  81                 dev_info(&cdev->device, "%s bind to %d: %d-%s\n", cdev->type,
  82                         i, ret, ret ? "fail" : "succeed");
  83         }
  84
  85         return ret;
  86 }
  87
  88 /* Callback to unbind cooling device from thermal zone */
  89 static int db8500_cdev_unbind(struct thermal_zone_device *thermal,
  90                 struct thermal_cooling_device *cdev)
  91 {
  92         struct db8500_thermal_zone *pzone = thermal->devdata;
  93         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
  94         int i, ret = -EINVAL;
  95
  96         for (i = 0; i < ptrips->num_trips; i++) {
  97                 if (db8500_thermal_match_cdev(cdev, &ptrips->trip_points[i]))
  98                         continue;
  99
 100                 ret = thermal_zone_unbind_cooling_device(thermal, i, cdev);
 101
 102                 dev_info(&cdev->device, "%s unbind from %d: %s\n", cdev->type,
 103                         i, ret ? "fail" : "succeed");
 104         }
 105
 106         return ret;
 107 }
 108
 109 /* Callback to get current temperature */
 110 static int db8500_sys_get_temp(struct thermal_zone_device *thermal, int *temp)
 111 {
 112         struct db8500_thermal_zone *pzone = thermal->devdata;
 113
 114         /*
 115          * TODO: There is no PRCMU interface to get temperature data currently,
 116          * so a pseudo temperature is returned , it works for thermal framework
 117          * and this will be fixed when the PRCMU interface is available.
 118          */
 119         *temp = pzone->cur_temp_pseudo;
 120
 121         return 0;
 122 }
 123
 124 /* Callback to get temperature changing trend */
 125 static int db8500_sys_get_trend(struct thermal_zone_device *thermal,
 126                 int trip, enum thermal_trend *trend)
 127 {
 128         struct db8500_thermal_zone *pzone = thermal->devdata;
 129
 130         *trend = pzone->trend;
 131
 132         return 0;
 133 }
 134
 135 /* Callback to get thermal zone mode */
 136 static int db8500_sys_get_mode(struct thermal_zone_device *thermal,
 137                 enum thermal_device_mode *mode)
 138 {
 139         struct db8500_thermal_zone *pzone = thermal->devdata;
 140
 141         mutex_lock(&pzone->th_lock);
 142         *mode = pzone->mode;
 143         mutex_unlock(&pzone->th_lock);
 144
 145         return 0;
 146 }
 147
 148 /* Callback to set thermal zone mode */
 149 static int db8500_sys_set_mode(struct thermal_zone_device *thermal,
 150                 enum thermal_device_mode mode)
 151 {
 152         struct db8500_thermal_zone *pzone = thermal->devdata;
 153
 154         mutex_lock(&pzone->th_lock);
 155
 156         pzone->mode = mode;
 157         if (mode == THERMAL_DEVICE_ENABLED)
 158                 schedule_work(&pzone->therm_work);
 159
 160         mutex_unlock(&pzone->th_lock);
 161
 162         return 0;
 163 }
 164
 165 /* Callback to get trip point type */
 166 static int db8500_sys_get_trip_type(struct thermal_zone_device *thermal,
 167                 int trip, enum thermal_trip_type *type)
 168 {
 169         struct db8500_thermal_zone *pzone = thermal->devdata;
 170         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 171
 172         if (trip >= ptrips->num_trips)
 173                 return -EINVAL;
 174
 175         *type = ptrips->trip_points[trip].type;
 176
 177         return 0;
 178 }
 179
 180 /* Callback to get trip point temperature */
 181 static int db8500_sys_get_trip_temp(struct thermal_zone_device *thermal,
 182                 int trip, int *temp)
 183 {
 184         struct db8500_thermal_zone *pzone = thermal->devdata;
 185         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 186
 187         if (trip >= ptrips->num_trips)
 188                 return -EINVAL;
 189
 190         *temp = ptrips->trip_points[trip].temp;
 191
 192         return 0;
 193 }
 194
 195 /* Callback to get critical trip point temperature */
 196 static int db8500_sys_get_crit_temp(struct thermal_zone_device *thermal,
 197                 int *temp)
 198 {
 199         struct db8500_thermal_zone *pzone = thermal->devdata;
 200         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 201         int i;
 202
 203         for (i = ptrips->num_trips - 1; i > 0; i--) {
 204                 if (ptrips->trip_points[i].type == THERMAL_TRIP_CRITICAL) {
 205                         *temp = ptrips->trip_points[i].temp;
 206                         return 0;
 207                 }
 208         }
 209
 210         return -EINVAL;
 211 }
 212
 213 static struct thermal_zone_device_ops thdev_ops = {
 214         .bind = db8500_cdev_bind,
 215         .unbind = db8500_cdev_unbind,
 216         .get_temp = db8500_sys_get_temp,
 217         .get_trend = db8500_sys_get_trend,
 218         .get_mode = db8500_sys_get_mode,
 219         .set_mode = db8500_sys_set_mode,
 220         .get_trip_type = db8500_sys_get_trip_type,
 221         .get_trip_temp = db8500_sys_get_trip_temp,
 222         .get_crit_temp = db8500_sys_get_crit_temp,
 223 };
 224
 225 static void db8500_thermal_update_config(struct db8500_thermal_zone *pzone,
 226                 unsigned int idx, enum thermal_trend trend,
 227                 unsigned long next_low, unsigned long next_high)
 228 {
 229         prcmu_stop_temp_sense();
 230
 231         pzone->cur_index = idx;
 232         pzone->cur_temp_pseudo = (next_low + next_high)/2;
 233         pzone->trend = trend;
 234
 235         prcmu_config_hotmon((u8)(next_low/1000), (u8)(next_high/1000));
 236         prcmu_start_temp_sense(PRCMU_DEFAULT_MEASURE_TIME);
 237 }
 238
 239 static irqreturn_t prcmu_low_irq_handler(int irq, void *irq_data)
 240 {
 241         struct db8500_thermal_zone *pzone = irq_data;
 242         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 243         unsigned int idx = pzone->cur_index;
 244         unsigned long next_low, next_high;
 245
 246         if (unlikely(idx == 0))
 247                 /* Meaningless for thermal management, ignoring it */
 248                 return IRQ_HANDLED;
 249
 250         if (idx == 1) {
 251                 next_high = ptrips->trip_points[0].temp;
 252                 next_low = PRCMU_DEFAULT_LOW_TEMP;
 253         } else {
 254                 next_high = ptrips->trip_points[idx-1].temp;
 255                 next_low = ptrips->trip_points[idx-2].temp;
 256         }
 257         idx -= 1;
 258
 259         db8500_thermal_update_config(pzone, idx, THERMAL_TREND_DROPPING,
 260                 next_low, next_high);
 261
 262         dev_dbg(&pzone->therm_dev->device,
 263                 "PRCMU set max %ld, min %ld\n", next_high, next_low);
 264
 265         schedule_work(&pzone->therm_work);
 266
 267         return IRQ_HANDLED;
 268 }
 269
 270 static irqreturn_t prcmu_high_irq_handler(int irq, void *irq_data)
 271 {
 272         struct db8500_thermal_zone *pzone = irq_data;
 273         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 274         unsigned int idx = pzone->cur_index;
 275         unsigned long next_low, next_high;
 276
 277         if (idx < ptrips->num_trips - 1) {
 278                 next_high = ptrips->trip_points[idx+1].temp;
 279                 next_low = ptrips->trip_points[idx].temp;
 280                 idx += 1;
 281
 282                 db8500_thermal_update_config(pzone, idx, THERMAL_TREND_RAISING,
 283                         next_low, next_high);
 284
 285                 dev_dbg(&pzone->therm_dev->device,
 286                 "PRCMU set max %ld, min %ld\n", next_high, next_low);
 287         } else if (idx == ptrips->num_trips - 1)
 288                 pzone->cur_temp_pseudo = ptrips->trip_points[idx].temp + 1;
 289
 290         schedule_work(&pzone->therm_work);
 291
 292         return IRQ_HANDLED;
 293 }
 294
 295 static void db8500_thermal_work(struct work_struct *work)
 296 {
 297         enum thermal_device_mode cur_mode;
 298         struct db8500_thermal_zone *pzone;
 299
 300         pzone = container_of(work, struct db8500_thermal_zone, therm_work);
 301
 302         mutex_lock(&pzone->th_lock);
 303         cur_mode = pzone->mode;
 304         mutex_unlock(&pzone->th_lock);
 305
 306         if (cur_mode == THERMAL_DEVICE_DISABLED)
 307                 return;
 308
 309         thermal_zone_device_update(pzone->therm_dev, THERMAL_EVENT_UNSPECIFIED);
 310         dev_dbg(&pzone->therm_dev->device, "thermal work finished.\n");
 311 }
 312
 313 #ifdef CONFIG_OF
 314 static struct db8500_thsens_platform_data*
 315                 db8500_thermal_parse_dt(struct platform_device *pdev)
 316 {
 317         struct db8500_thsens_platform_data *ptrips;
 318         struct device_node *np = pdev->dev.of_node;
 319         char prop_name[32];
 320         const char *tmp_str;
 321         u32 tmp_data;
 322         int i, j;
 323
 324         ptrips = devm_kzalloc(&pdev->dev, sizeof(*ptrips), GFP_KERNEL);
 325         if (!ptrips)
 326                 return NULL;
 327
 328         if (of_property_read_u32(np, "num-trips", &tmp_data))
 329                 goto err_parse_dt;
 330
 331         if (tmp_data > THERMAL_MAX_TRIPS)
 332                 goto err_parse_dt;
 333
 334         ptrips->num_trips = tmp_data;
 335
 336         for (i = 0; i < ptrips->num_trips; i++) {
 337                 sprintf(prop_name, "trip%d-temp", i);
 338                 if (of_property_read_u32(np, prop_name, &tmp_data))
 339                         goto err_parse_dt;
 340
 341                 ptrips->trip_points[i].temp = tmp_data;
 342
 343                 sprintf(prop_name, "trip%d-type", i);
 344                 if (of_property_read_string(np, prop_name, &tmp_str))
 345                         goto err_parse_dt;
 346
 347                 if (!strcmp(tmp_str, "active"))
 348                         ptrips->trip_points[i].type = THERMAL_TRIP_ACTIVE;
 349                 else if (!strcmp(tmp_str, "passive"))
 350                         ptrips->trip_points[i].type = THERMAL_TRIP_PASSIVE;
 351                 else if (!strcmp(tmp_str, "hot"))
 352                         ptrips->trip_points[i].type = THERMAL_TRIP_HOT;
 353                 else if (!strcmp(tmp_str, "critical"))
 354                         ptrips->trip_points[i].type = THERMAL_TRIP_CRITICAL;
 355                 else
 356                         goto err_parse_dt;
 357
 358                 sprintf(prop_name, "trip%d-cdev-num", i);
 359                 if (of_property_read_u32(np, prop_name, &tmp_data))
 360                         goto err_parse_dt;
 361
 362                 if (tmp_data > COOLING_DEV_MAX)
 363                         goto err_parse_dt;
 364
 365                 for (j = 0; j < tmp_data; j++) {
 366                         sprintf(prop_name, "trip%d-cdev-name%d", i, j);
 367                         if (of_property_read_string(np, prop_name, &tmp_str))
 368                                 goto err_parse_dt;
 369
 370                         if (strlen(tmp_str) >= THERMAL_NAME_LENGTH)
 371                                 goto err_parse_dt;
 372
 373                         strcpy(ptrips->trip_points[i].cdev_name[j], tmp_str);
 374                 }
 375         }
 376         return ptrips;
 377
 378 err_parse_dt:
 379         dev_err(&pdev->dev, "Parsing device tree data error.\n");
 380         return NULL;
 381 }
 382 #else
 383 static inline struct db8500_thsens_platform_data*
 384                 db8500_thermal_parse_dt(struct platform_device *pdev)
 385 {
 386         return NULL;
 387 }
 388 #endif
 389
 390 static int db8500_thermal_probe(struct platform_device *pdev)
 391 {
 392         struct db8500_thermal_zone *pzone = NULL;
 393         struct db8500_thsens_platform_data *ptrips = NULL;
 394         struct device_node *np = pdev->dev.of_node;
 395         int low_irq, high_irq, ret = 0;
 396         unsigned long dft_low, dft_high;
 397
 398         if (np)
 399                 ptrips = db8500_thermal_parse_dt(pdev);
 400         else
 401                 ptrips = dev_get_platdata(&pdev->dev);
 402
 403         if (!ptrips)
 404                 return -EINVAL;
 405
 406         pzone = devm_kzalloc(&pdev->dev, sizeof(*pzone), GFP_KERNEL);
 407         if (!pzone)
 408                 return -ENOMEM;
 409
 410         mutex_init(&pzone->th_lock);
 411         mutex_lock(&pzone->th_lock);
 412
 413         pzone->mode = THERMAL_DEVICE_DISABLED;
 414         pzone->trip_tab = ptrips;
 415
 416         INIT_WORK(&pzone->therm_work, db8500_thermal_work);
 417
 418         low_irq = platform_get_irq_byname(pdev, "IRQ_HOTMON_LOW");
 419         if (low_irq < 0) {
 420                 dev_err(&pdev->dev, "Get IRQ_HOTMON_LOW failed.\n");
 421                 ret = low_irq;
 422                 goto out_unlock;
 423         }
 424
 425         ret = devm_request_threaded_irq(&pdev->dev, low_irq, NULL,
 426                 prcmu_low_irq_handler, IRQF_NO_SUSPEND | IRQF_ONESHOT,
 427                 "dbx500_temp_low", pzone);
 428         if (ret < 0) {
 429                 dev_err(&pdev->dev, "Failed to allocate temp low irq.\n");
 430                 goto out_unlock;
 431         }
 432
 433         high_irq = platform_get_irq_byname(pdev, "IRQ_HOTMON_HIGH");
 434         if (high_irq < 0) {
 435                 dev_err(&pdev->dev, "Get IRQ_HOTMON_HIGH failed.\n");
 436                 ret = high_irq;
 437                 goto out_unlock;
 438         }
 439
 440         ret = devm_request_threaded_irq(&pdev->dev, high_irq, NULL,
 441                 prcmu_high_irq_handler, IRQF_NO_SUSPEND | IRQF_ONESHOT,
 442                 "dbx500_temp_high", pzone);
 443         if (ret < 0) {
 444                 dev_err(&pdev->dev, "Failed to allocate temp high irq.\n");
 445                 goto out_unlock;
 446         }
 447
 448         pzone->therm_dev = thermal_zone_device_register("db8500_thermal_zone",
 449                 ptrips->num_trips, 0, pzone, &thdev_ops, NULL, 0, 0);
 450
 451         if (IS_ERR(pzone->therm_dev)) {
 452                 dev_err(&pdev->dev, "Register thermal zone device failed.\n");
 453                 ret = PTR_ERR(pzone->therm_dev);
 454                 goto out_unlock;
 455         }
 456         dev_info(&pdev->dev, "Thermal zone device registered.\n");
 457
 458         dft_low = PRCMU_DEFAULT_LOW_TEMP;
 459         dft_high = ptrips->trip_points[0].temp;
 460
 461         db8500_thermal_update_config(pzone, 0, THERMAL_TREND_STABLE,
 462                 dft_low, dft_high);
 463
 464         platform_set_drvdata(pdev, pzone);
 465         pzone->mode = THERMAL_DEVICE_ENABLED;
 466
 467 out_unlock:
 468         mutex_unlock(&pzone->th_lock);
 469
 470         return ret;
 471 }
 472
 473 static int db8500_thermal_remove(struct platform_device *pdev)
 474 {
 475         struct db8500_thermal_zone *pzone = platform_get_drvdata(pdev);
 476
 477         thermal_zone_device_unregister(pzone->therm_dev);
 478         cancel_work_sync(&pzone->therm_work);
 479         mutex_destroy(&pzone->th_lock);
 480
 481         return 0;
 482 }
 483
 484 static int db8500_thermal_suspend(struct platform_device *pdev,
 485                 pm_message_t state)
 486 {
 487         struct db8500_thermal_zone *pzone = platform_get_drvdata(pdev);
 488
 489         flush_work(&pzone->therm_work);
 490         prcmu_stop_temp_sense();
 491
 492         return 0;
 493 }
 494
 495 static int db8500_thermal_resume(struct platform_device *pdev)
 496 {
 497         struct db8500_thermal_zone *pzone = platform_get_drvdata(pdev);
 498         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 499         unsigned long dft_low, dft_high;
 500
 501         dft_low = PRCMU_DEFAULT_LOW_TEMP;
 502         dft_high = ptrips->trip_points[0].temp;
 503
 504         db8500_thermal_update_config(pzone, 0, THERMAL_TREND_STABLE,
 505                 dft_low, dft_high);
 506
 507         return 0;
 508 }
 509
 510 #ifdef CONFIG_OF
 511 static const struct of_device_id db8500_thermal_match[] = {
 512         { .compatible = "stericsson,db8500-thermal" },
 513         {},
 514 };
 515 MODULE_DEVICE_TABLE(of, db8500_thermal_match);
 516 #endif
 517
 518 static struct platform_driver db8500_thermal_driver = {
 519         .driver = {
 520                 .name = "db8500-thermal",
 521                 .of_match_table = of_match_ptr(db8500_thermal_match),
 522         },
 523         .probe = db8500_thermal_probe,
 524         .suspend = db8500_thermal_suspend,
 525         .resume = db8500_thermal_resume,
 526         .remove = db8500_thermal_remove,
 527 };
 528
 529 module_platform_driver(db8500_thermal_driver);
 530
 531 MODULE_AUTHOR("Hongbo Zhang <hongbo.zhang@stericsson.com>");
 532 MODULE_DESCRIPTION("DB8500 thermal driver");
 533 MODULE_LICENSE("GPL");