kernel/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);
  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,
 111                 unsigned long *temp)
 112 {
 113         struct db8500_thermal_zone *pzone = thermal->devdata;
 114
 115         /*
 116          * TODO: There is no PRCMU interface to get temperature data currently,
 117          * so a pseudo temperature is returned , it works for thermal framework
 118          * and this will be fixed when the PRCMU interface is available.
 119          */
 120         *temp = pzone->cur_temp_pseudo;
 121
 122         return 0;
 123 }
 124
 125 /* Callback to get temperature changing trend */
 126 static int db8500_sys_get_trend(struct thermal_zone_device *thermal,
 127                 int trip, enum thermal_trend *trend)
 128 {
 129         struct db8500_thermal_zone *pzone = thermal->devdata;
 130
 131         *trend = pzone->trend;
 132
 133         return 0;
 134 }
 135
 136 /* Callback to get thermal zone mode */
 137 static int db8500_sys_get_mode(struct thermal_zone_device *thermal,
 138                 enum thermal_device_mode *mode)
 139 {
 140         struct db8500_thermal_zone *pzone = thermal->devdata;
 141
 142         mutex_lock(&pzone->th_lock);
 143         *mode = pzone->mode;
 144         mutex_unlock(&pzone->th_lock);
 145
 146         return 0;
 147 }
 148
 149 /* Callback to set thermal zone mode */
 150 static int db8500_sys_set_mode(struct thermal_zone_device *thermal,
 151                 enum thermal_device_mode mode)
 152 {
 153         struct db8500_thermal_zone *pzone = thermal->devdata;
 154
 155         mutex_lock(&pzone->th_lock);
 156
 157         pzone->mode = mode;
 158         if (mode == THERMAL_DEVICE_ENABLED)
 159                 schedule_work(&pzone->therm_work);
 160
 161         mutex_unlock(&pzone->th_lock);
 162
 163         return 0;
 164 }
 165
 166 /* Callback to get trip point type */
 167 static int db8500_sys_get_trip_type(struct thermal_zone_device *thermal,
 168                 int trip, enum thermal_trip_type *type)
 169 {
 170         struct db8500_thermal_zone *pzone = thermal->devdata;
 171         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 172
 173         if (trip >= ptrips->num_trips)
 174                 return -EINVAL;
 175
 176         *type = ptrips->trip_points[trip].type;
 177
 178         return 0;
 179 }
 180
 181 /* Callback to get trip point temperature */
 182 static int db8500_sys_get_trip_temp(struct thermal_zone_device *thermal,
 183                 int trip, unsigned long *temp)
 184 {
 185         struct db8500_thermal_zone *pzone = thermal->devdata;
 186         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 187
 188         if (trip >= ptrips->num_trips)
 189                 return -EINVAL;
 190
 191         *temp = ptrips->trip_points[trip].temp;
 192
 193         return 0;
 194 }
 195
 196 /* Callback to get critical trip point temperature */
 197 static int db8500_sys_get_crit_temp(struct thermal_zone_device *thermal,
 198                 unsigned long *temp)
 199 {
 200         struct db8500_thermal_zone *pzone = thermal->devdata;
 201         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 202         int i;
 203
 204         for (i = ptrips->num_trips - 1; i > 0; i--) {
 205                 if (ptrips->trip_points[i].type == THERMAL_TRIP_CRITICAL) {
 206                         *temp = ptrips->trip_points[i].temp;
 207                         return 0;
 208                 }
 209         }
 210
 211         return -EINVAL;
 212 }
 213
 214 static struct thermal_zone_device_ops thdev_ops = {
 215         .bind = db8500_cdev_bind,
 216         .unbind = db8500_cdev_unbind,
 217         .get_temp = db8500_sys_get_temp,
 218         .get_trend = db8500_sys_get_trend,
 219         .get_mode = db8500_sys_get_mode,
 220         .set_mode = db8500_sys_set_mode,
 221         .get_trip_type = db8500_sys_get_trip_type,
 222         .get_trip_temp = db8500_sys_get_trip_temp,
 223         .get_crit_temp = db8500_sys_get_crit_temp,
 224 };
 225
 226 static void db8500_thermal_update_config(struct db8500_thermal_zone *pzone,
 227                 unsigned int idx, enum thermal_trend trend,
 228                 unsigned long next_low, unsigned long next_high)
 229 {
 230         prcmu_stop_temp_sense();
 231
 232         pzone->cur_index = idx;
 233         pzone->cur_temp_pseudo = (next_low + next_high)/2;
 234         pzone->trend = trend;
 235
 236         prcmu_config_hotmon((u8)(next_low/1000), (u8)(next_high/1000));
 237         prcmu_start_temp_sense(PRCMU_DEFAULT_MEASURE_TIME);
 238 }
 239
 240 static irqreturn_t prcmu_low_irq_handler(int irq, void *irq_data)
 241 {
 242         struct db8500_thermal_zone *pzone = irq_data;
 243         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 244         unsigned int idx = pzone->cur_index;
 245         unsigned long next_low, next_high;
 246
 247         if (unlikely(idx == 0))
 248                 /* Meaningless for thermal management, ignoring it */
 249                 return IRQ_HANDLED;
 250
 251         if (idx == 1) {
 252                 next_high = ptrips->trip_points[0].temp;
 253                 next_low = PRCMU_DEFAULT_LOW_TEMP;
 254         } else {
 255                 next_high = ptrips->trip_points[idx-1].temp;
 256                 next_low = ptrips->trip_points[idx-2].temp;
 257         }
 258         idx -= 1;
 259
 260         db8500_thermal_update_config(pzone, idx, THERMAL_TREND_DROPPING,
 261                 next_low, next_high);
 262
 263         dev_dbg(&pzone->therm_dev->device,
 264                 "PRCMU set max %ld, min %ld\n", next_high, next_low);
 265
 266         schedule_work(&pzone->therm_work);
 267
 268         return IRQ_HANDLED;
 269 }
 270
 271 static irqreturn_t prcmu_high_irq_handler(int irq, void *irq_data)
 272 {
 273         struct db8500_thermal_zone *pzone = irq_data;
 274         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 275         unsigned int idx = pzone->cur_index;
 276         unsigned long next_low, next_high;
 277
 278         if (idx < ptrips->num_trips - 1) {
 279                 next_high = ptrips->trip_points[idx+1].temp;
 280                 next_low = ptrips->trip_points[idx].temp;
 281                 idx += 1;
 282
 283                 db8500_thermal_update_config(pzone, idx, THERMAL_TREND_RAISING,
 284                         next_low, next_high);
 285
 286                 dev_dbg(&pzone->therm_dev->device,
 287                 "PRCMU set max %ld, min %ld\n", next_high, next_low);
 288         } else if (idx == ptrips->num_trips - 1)
 289                 pzone->cur_temp_pseudo = ptrips->trip_points[idx].temp + 1;
 290
 291         schedule_work(&pzone->therm_work);
 292
 293         return IRQ_HANDLED;
 294 }
 295
 296 static void db8500_thermal_work(struct work_struct *work)
 297 {
 298         enum thermal_device_mode cur_mode;
 299         struct db8500_thermal_zone *pzone;
 300
 301         pzone = container_of(work, struct db8500_thermal_zone, therm_work);
 302
 303         mutex_lock(&pzone->th_lock);
 304         cur_mode = pzone->mode;
 305         mutex_unlock(&pzone->th_lock);
 306
 307         if (cur_mode == THERMAL_DEVICE_DISABLED)
 308                 return;
 309
 310         thermal_zone_device_update(pzone->therm_dev);
 311         dev_dbg(&pzone->therm_dev->device, "thermal work finished.\n");
 312 }
 313
 314 #ifdef CONFIG_OF
 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 #else
 384 static inline struct db8500_thsens_platform_data*
 385                 db8500_thermal_parse_dt(struct platform_device *pdev)
 386 {
 387         return NULL;
 388 }
 389 #endif
 390
 391 static int db8500_thermal_probe(struct platform_device *pdev)
 392 {
 393         struct db8500_thermal_zone *pzone = NULL;
 394         struct db8500_thsens_platform_data *ptrips = NULL;
 395         struct device_node *np = pdev->dev.of_node;
 396         int low_irq, high_irq, ret = 0;
 397         unsigned long dft_low, dft_high;
 398
 399         if (np)
 400                 ptrips = db8500_thermal_parse_dt(pdev);
 401         else
 402                 ptrips = dev_get_platdata(&pdev->dev);
 403
 404         if (!ptrips)
 405                 return -EINVAL;
 406
 407         pzone = devm_kzalloc(&pdev->dev, sizeof(*pzone), GFP_KERNEL);
 408         if (!pzone)
 409                 return -ENOMEM;
 410
 411         mutex_init(&pzone->th_lock);
 412         mutex_lock(&pzone->th_lock);
 413
 414         pzone->mode = THERMAL_DEVICE_DISABLED;
 415         pzone->trip_tab = ptrips;
 416
 417         INIT_WORK(&pzone->therm_work, db8500_thermal_work);
 418
 419         low_irq = platform_get_irq_byname(pdev, "IRQ_HOTMON_LOW");
 420         if (low_irq < 0) {
 421                 dev_err(&pdev->dev, "Get IRQ_HOTMON_LOW failed.\n");
 422                 ret = low_irq;
 423                 goto out_unlock;
 424         }
 425
 426         ret = devm_request_threaded_irq(&pdev->dev, low_irq, NULL,
 427                 prcmu_low_irq_handler, IRQF_NO_SUSPEND | IRQF_ONESHOT,
 428                 "dbx500_temp_low", pzone);
 429         if (ret < 0) {
 430                 dev_err(&pdev->dev, "Failed to allocate temp low irq.\n");
 431                 goto out_unlock;
 432         }
 433
 434         high_irq = platform_get_irq_byname(pdev, "IRQ_HOTMON_HIGH");
 435         if (high_irq < 0) {
 436                 dev_err(&pdev->dev, "Get IRQ_HOTMON_HIGH failed.\n");
 437                 ret = high_irq;
 438                 goto out_unlock;
 439         }
 440
 441         ret = devm_request_threaded_irq(&pdev->dev, high_irq, NULL,
 442                 prcmu_high_irq_handler, IRQF_NO_SUSPEND | IRQF_ONESHOT,
 443                 "dbx500_temp_high", pzone);
 444         if (ret < 0) {
 445                 dev_err(&pdev->dev, "Failed to allocate temp high irq.\n");
 446                 goto out_unlock;
 447         }
 448
 449         pzone->therm_dev = thermal_zone_device_register("db8500_thermal_zone",
 450                 ptrips->num_trips, 0, pzone, &thdev_ops, NULL, 0, 0);
 451
 452         if (IS_ERR(pzone->therm_dev)) {
 453                 dev_err(&pdev->dev, "Register thermal zone device failed.\n");
 454                 ret = PTR_ERR(pzone->therm_dev);
 455                 goto out_unlock;
 456         }
 457         dev_info(&pdev->dev, "Thermal zone device registered.\n");
 458
 459         dft_low = PRCMU_DEFAULT_LOW_TEMP;
 460         dft_high = ptrips->trip_points[0].temp;
 461
 462         db8500_thermal_update_config(pzone, 0, THERMAL_TREND_STABLE,
 463                 dft_low, dft_high);
 464
 465         platform_set_drvdata(pdev, pzone);
 466         pzone->mode = THERMAL_DEVICE_ENABLED;
 467
 468 out_unlock:
 469         mutex_unlock(&pzone->th_lock);
 470
 471         return ret;
 472 }
 473
 474 static int db8500_thermal_remove(struct platform_device *pdev)
 475 {
 476         struct db8500_thermal_zone *pzone = platform_get_drvdata(pdev);
 477
 478         thermal_zone_device_unregister(pzone->therm_dev);
 479         cancel_work_sync(&pzone->therm_work);
 480         mutex_destroy(&pzone->th_lock);
 481
 482         return 0;
 483 }
 484
 485 static int db8500_thermal_suspend(struct platform_device *pdev,
 486                 pm_message_t state)
 487 {
 488         struct db8500_thermal_zone *pzone = platform_get_drvdata(pdev);
 489
 490         flush_work(&pzone->therm_work);
 491         prcmu_stop_temp_sense();
 492
 493         return 0;
 494 }
 495
 496 static int db8500_thermal_resume(struct platform_device *pdev)
 497 {
 498         struct db8500_thermal_zone *pzone = platform_get_drvdata(pdev);
 499         struct db8500_thsens_platform_data *ptrips = pzone->trip_tab;
 500         unsigned long dft_low, dft_high;
 501
 502         dft_low = PRCMU_DEFAULT_LOW_TEMP;
 503         dft_high = ptrips->trip_points[0].temp;
 504
 505         db8500_thermal_update_config(pzone, 0, THERMAL_TREND_STABLE,
 506                 dft_low, dft_high);
 507
 508         return 0;
 509 }
 510
 511 #ifdef CONFIG_OF
 512 static const struct of_device_id db8500_thermal_match[] = {
 513         { .compatible = "stericsson,db8500-thermal" },
 514         {},
 515 };
 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");