drivers/thermal/imx_thermal.c

   1 /*
   2  * Copyright 2013 Freescale Semiconductor, Inc.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  */
   9
  10 #include <linux/clk.h>
  11 #include <linux/cpu_cooling.h>
  12 #include <linux/delay.h>
  13 #include <linux/device.h>
  14 #include <linux/init.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/io.h>
  17 #include <linux/kernel.h>
  18 #include <linux/mfd/syscon.h>
  19 #include <linux/module.h>
  20 #include <linux/of.h>
  21 #include <linux/of_device.h>
  22 #include <linux/platform_device.h>
  23 #include <linux/regmap.h>
  24 #include <linux/slab.h>
  25 #include <linux/thermal.h>
  26 #include <linux/types.h>
  27
  28 #define REG_SET         0x4
  29 #define REG_CLR         0x8
  30 #define REG_TOG         0xc
  31
  32 #define MISC0                           0x0150
  33 #define MISC0_REFTOP_SELBIASOFF         (1 << 3)
  34 #define MISC1                           0x0160
  35 #define MISC1_IRQ_TEMPHIGH              (1 << 29)
  36 /* Below LOW and PANIC bits are only for TEMPMON_IMX6SX */
  37 #define MISC1_IRQ_TEMPLOW               (1 << 28)
  38 #define MISC1_IRQ_TEMPPANIC             (1 << 27)
  39
  40 #define TEMPSENSE0                      0x0180
  41 #define TEMPSENSE0_ALARM_VALUE_SHIFT    20
  42 #define TEMPSENSE0_ALARM_VALUE_MASK     (0xfff << TEMPSENSE0_ALARM_VALUE_SHIFT)
  43 #define TEMPSENSE0_TEMP_CNT_SHIFT       8
  44 #define TEMPSENSE0_TEMP_CNT_MASK        (0xfff << TEMPSENSE0_TEMP_CNT_SHIFT)
  45 #define TEMPSENSE0_FINISHED             (1 << 2)
  46 #define TEMPSENSE0_MEASURE_TEMP         (1 << 1)
  47 #define TEMPSENSE0_POWER_DOWN           (1 << 0)
  48
  49 #define TEMPSENSE1                      0x0190
  50 #define TEMPSENSE1_MEASURE_FREQ         0xffff
  51 /* Below TEMPSENSE2 is only for TEMPMON_IMX6SX */
  52 #define TEMPSENSE2                      0x0290
  53 #define TEMPSENSE2_LOW_VALUE_SHIFT      0
  54 #define TEMPSENSE2_LOW_VALUE_MASK       0xfff
  55 #define TEMPSENSE2_PANIC_VALUE_SHIFT    16
  56 #define TEMPSENSE2_PANIC_VALUE_MASK     0xfff0000
  57
  58 #define OCOTP_MEM0                      0x0480
  59 #define OCOTP_ANA1                      0x04e0
  60
  61 /* The driver supports 1 passive trip point and 1 critical trip point */
  62 enum imx_thermal_trip {
  63         IMX_TRIP_PASSIVE,
  64         IMX_TRIP_CRITICAL,
  65         IMX_TRIP_NUM,
  66 };
  67
  68 #define IMX_POLLING_DELAY               2000 /* millisecond */
  69 #define IMX_PASSIVE_DELAY               1000
  70
  71 #define FACTOR0                         10000000
  72 #define FACTOR1                         15976
  73 #define FACTOR2                         4297157
  74
  75 #define TEMPMON_IMX6Q                   1
  76 #define TEMPMON_IMX6SX                  2
  77
  78 struct thermal_soc_data {
  79         u32 version;
  80 };
  81
  82 static struct thermal_soc_data thermal_imx6q_data = {
  83         .version = TEMPMON_IMX6Q,
  84 };
  85
  86 static struct thermal_soc_data thermal_imx6sx_data = {
  87         .version = TEMPMON_IMX6SX,
  88 };
  89
  90 struct imx_thermal_data {
  91         struct thermal_zone_device *tz;
  92         struct thermal_cooling_device *cdev;
  93         enum thermal_device_mode mode;
  94         struct regmap *tempmon;
  95         u32 c1, c2; /* See formula in imx_get_sensor_data() */
  96         int temp_passive;
  97         int temp_critical;
  98         int temp_max;
  99         int alarm_temp;
 100         int last_temp;
 101         bool irq_enabled;
 102         int irq;
 103         struct clk *thermal_clk;
 104         const struct thermal_soc_data *socdata;
 105         const char *temp_grade;
 106 };
 107
 108 static void imx_set_panic_temp(struct imx_thermal_data *data,
 109                                int panic_temp)
 110 {
 111         struct regmap *map = data->tempmon;
 112         int critical_value;
 113
 114         critical_value = (data->c2 - panic_temp) / data->c1;
 115         regmap_write(map, TEMPSENSE2 + REG_CLR, TEMPSENSE2_PANIC_VALUE_MASK);
 116         regmap_write(map, TEMPSENSE2 + REG_SET, critical_value <<
 117                         TEMPSENSE2_PANIC_VALUE_SHIFT);
 118 }
 119
 120 static void imx_set_alarm_temp(struct imx_thermal_data *data,
 121                                int alarm_temp)
 122 {
 123         struct regmap *map = data->tempmon;
 124         int alarm_value;
 125
 126         data->alarm_temp = alarm_temp;
 127         alarm_value = (data->c2 - alarm_temp) / data->c1;
 128         regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_ALARM_VALUE_MASK);
 129         regmap_write(map, TEMPSENSE0 + REG_SET, alarm_value <<
 130                         TEMPSENSE0_ALARM_VALUE_SHIFT);
 131 }
 132
 133 static int imx_get_temp(struct thermal_zone_device *tz, int *temp)
 134 {
 135         struct imx_thermal_data *data = tz->devdata;
 136         struct regmap *map = data->tempmon;
 137         unsigned int n_meas;
 138         bool wait;
 139         u32 val;
 140
 141         if (data->mode == THERMAL_DEVICE_ENABLED) {
 142                 /* Check if a measurement is currently in progress */
 143                 regmap_read(map, TEMPSENSE0, &val);
 144                 wait = !(val & TEMPSENSE0_FINISHED);
 145         } else {
 146                 /*
 147                  * Every time we measure the temperature, we will power on the
 148                  * temperature sensor, enable measurements, take a reading,
 149                  * disable measurements, power off the temperature sensor.
 150                  */
 151                 regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
 152                 regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
 153
 154                 wait = true;
 155         }
 156
 157         /*
 158          * According to the temp sensor designers, it may require up to ~17us
 159          * to complete a measurement.
 160          */
 161         if (wait)
 162                 usleep_range(20, 50);
 163
 164         regmap_read(map, TEMPSENSE0, &val);
 165
 166         if (data->mode != THERMAL_DEVICE_ENABLED) {
 167                 regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
 168                 regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
 169         }
 170
 171         if ((val & TEMPSENSE0_FINISHED) == 0) {
 172                 dev_dbg(&tz->device, "temp measurement never finished\n");
 173                 return -EAGAIN;
 174         }
 175
 176         n_meas = (val & TEMPSENSE0_TEMP_CNT_MASK) >> TEMPSENSE0_TEMP_CNT_SHIFT;
 177
 178         /* See imx_get_sensor_data() for formula derivation */
 179         *temp = data->c2 - n_meas * data->c1;
 180
 181         /* Update alarm value to next higher trip point for TEMPMON_IMX6Q */
 182         if (data->socdata->version == TEMPMON_IMX6Q) {
 183                 if (data->alarm_temp == data->temp_passive &&
 184                         *temp >= data->temp_passive)
 185                         imx_set_alarm_temp(data, data->temp_critical);
 186                 if (data->alarm_temp == data->temp_critical &&
 187                         *temp < data->temp_passive) {
 188                         imx_set_alarm_temp(data, data->temp_passive);
 189                         dev_dbg(&tz->device, "thermal alarm off: T < %d\n",
 190                                 data->alarm_temp / 1000);
 191                 }
 192         }
 193
 194         if (*temp != data->last_temp) {
 195                 dev_dbg(&tz->device, "millicelsius: %d\n", *temp);
 196                 data->last_temp = *temp;
 197         }
 198
 199         /* Reenable alarm IRQ if temperature below alarm temperature */
 200         if (!data->irq_enabled && *temp < data->alarm_temp) {
 201                 data->irq_enabled = true;
 202                 enable_irq(data->irq);
 203         }
 204
 205         return 0;
 206 }
 207
 208 static int imx_get_mode(struct thermal_zone_device *tz,
 209                         enum thermal_device_mode *mode)
 210 {
 211         struct imx_thermal_data *data = tz->devdata;
 212
 213         *mode = data->mode;
 214
 215         return 0;
 216 }
 217
 218 static int imx_set_mode(struct thermal_zone_device *tz,
 219                         enum thermal_device_mode mode)
 220 {
 221         struct imx_thermal_data *data = tz->devdata;
 222         struct regmap *map = data->tempmon;
 223
 224         if (mode == THERMAL_DEVICE_ENABLED) {
 225                 tz->polling_delay = IMX_POLLING_DELAY;
 226                 tz->passive_delay = IMX_PASSIVE_DELAY;
 227
 228                 regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
 229                 regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
 230
 231                 if (!data->irq_enabled) {
 232                         data->irq_enabled = true;
 233                         enable_irq(data->irq);
 234                 }
 235         } else {
 236                 regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
 237                 regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
 238
 239                 tz->polling_delay = 0;
 240                 tz->passive_delay = 0;
 241
 242                 if (data->irq_enabled) {
 243                         disable_irq(data->irq);
 244                         data->irq_enabled = false;
 245                 }
 246         }
 247
 248         data->mode = mode;
 249         thermal_zone_device_update(tz);
 250
 251         return 0;
 252 }
 253
 254 static int imx_get_trip_type(struct thermal_zone_device *tz, int trip,
 255                              enum thermal_trip_type *type)
 256 {
 257         *type = (trip == IMX_TRIP_PASSIVE) ? THERMAL_TRIP_PASSIVE :
 258                                              THERMAL_TRIP_CRITICAL;
 259         return 0;
 260 }
 261
 262 static int imx_get_crit_temp(struct thermal_zone_device *tz, int *temp)
 263 {
 264         struct imx_thermal_data *data = tz->devdata;
 265
 266         *temp = data->temp_critical;
 267         return 0;
 268 }
 269
 270 static int imx_get_trip_temp(struct thermal_zone_device *tz, int trip,
 271                              int *temp)
 272 {
 273         struct imx_thermal_data *data = tz->devdata;
 274
 275         *temp = (trip == IMX_TRIP_PASSIVE) ? data->temp_passive :
 276                                              data->temp_critical;
 277         return 0;
 278 }
 279
 280 static int imx_set_trip_temp(struct thermal_zone_device *tz, int trip,
 281                              int temp)
 282 {
 283         struct imx_thermal_data *data = tz->devdata;
 284
 285         /* do not allow changing critical threshold */
 286         if (trip == IMX_TRIP_CRITICAL)
 287                 return -EPERM;
 288
 289         /* do not allow passive to be set higher than critical */
 290         if (temp < 0 || temp > data->temp_critical)
 291                 return -EINVAL;
 292
 293         data->temp_passive = temp;
 294
 295         imx_set_alarm_temp(data, temp);
 296
 297         return 0;
 298 }
 299
 300 static int imx_bind(struct thermal_zone_device *tz,
 301                     struct thermal_cooling_device *cdev)
 302 {
 303         int ret;
 304
 305         ret = thermal_zone_bind_cooling_device(tz, IMX_TRIP_PASSIVE, cdev,
 306                                                THERMAL_NO_LIMIT,
 307                                                THERMAL_NO_LIMIT,
 308                                                THERMAL_WEIGHT_DEFAULT);
 309         if (ret) {
 310                 dev_err(&tz->device,
 311                         "binding zone %s with cdev %s failed:%d\n",
 312                         tz->type, cdev->type, ret);
 313                 return ret;
 314         }
 315
 316         return 0;
 317 }
 318
 319 static int imx_unbind(struct thermal_zone_device *tz,
 320                       struct thermal_cooling_device *cdev)
 321 {
 322         int ret;
 323
 324         ret = thermal_zone_unbind_cooling_device(tz, IMX_TRIP_PASSIVE, cdev);
 325         if (ret) {
 326                 dev_err(&tz->device,
 327                         "unbinding zone %s with cdev %s failed:%d\n",
 328                         tz->type, cdev->type, ret);
 329                 return ret;
 330         }
 331
 332         return 0;
 333 }
 334
 335 static struct thermal_zone_device_ops imx_tz_ops = {
 336         .bind = imx_bind,
 337         .unbind = imx_unbind,
 338         .get_temp = imx_get_temp,
 339         .get_mode = imx_get_mode,
 340         .set_mode = imx_set_mode,
 341         .get_trip_type = imx_get_trip_type,
 342         .get_trip_temp = imx_get_trip_temp,
 343         .get_crit_temp = imx_get_crit_temp,
 344         .set_trip_temp = imx_set_trip_temp,
 345 };
 346
 347 static int imx_get_sensor_data(struct platform_device *pdev)
 348 {
 349         struct imx_thermal_data *data = platform_get_drvdata(pdev);
 350         struct regmap *map;
 351         int t1, n1;
 352         int ret;
 353         u32 val;
 354         u64 temp64;
 355
 356         map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
 357                                               "fsl,tempmon-data");
 358         if (IS_ERR(map)) {
 359                 ret = PTR_ERR(map);
 360                 dev_err(&pdev->dev, "failed to get sensor regmap: %d\n", ret);
 361                 return ret;
 362         }
 363
 364         ret = regmap_read(map, OCOTP_ANA1, &val);
 365         if (ret) {
 366                 dev_err(&pdev->dev, "failed to read sensor data: %d\n", ret);
 367                 return ret;
 368         }
 369
 370         if (val == 0 || val == ~0) {
 371                 dev_err(&pdev->dev, "invalid sensor calibration data\n");
 372                 return -EINVAL;
 373         }
 374
 375         /*
 376          * Sensor data layout:
 377          *   [31:20] - sensor value @ 25C
 378          * Use universal formula now and only need sensor value @ 25C
 379          * slope = 0.4297157 - (0.0015976 * 25C fuse)
 380          */
 381         n1 = val >> 20;
 382         t1 = 25; /* t1 always 25C */
 383
 384         /*
 385          * Derived from linear interpolation:
 386          * slope = 0.4297157 - (0.0015976 * 25C fuse)
 387          * slope = (FACTOR2 - FACTOR1 * n1) / FACTOR0
 388          * (Nmeas - n1) / (Tmeas - t1) = slope
 389          * We want to reduce this down to the minimum computation necessary
 390          * for each temperature read.  Also, we want Tmeas in millicelsius
 391          * and we don't want to lose precision from integer division. So...
 392          * Tmeas = (Nmeas - n1) / slope + t1
 393          * milli_Tmeas = 1000 * (Nmeas - n1) / slope + 1000 * t1
 394          * milli_Tmeas = -1000 * (n1 - Nmeas) / slope + 1000 * t1
 395          * Let constant c1 = (-1000 / slope)
 396          * milli_Tmeas = (n1 - Nmeas) * c1 + 1000 * t1
 397          * Let constant c2 = n1 *c1 + 1000 * t1
 398          * milli_Tmeas = c2 - Nmeas * c1
 399          */
 400         temp64 = FACTOR0;
 401         temp64 *= 1000;
 402         do_div(temp64, FACTOR1 * n1 - FACTOR2);
 403         data->c1 = temp64;
 404         data->c2 = n1 * data->c1 + 1000 * t1;
 405
 406         /* use OTP for thermal grade */
 407         ret = regmap_read(map, OCOTP_MEM0, &val);
 408         if (ret) {
 409                 dev_err(&pdev->dev, "failed to read temp grade: %d\n", ret);
 410                 return ret;
 411         }
 412
 413         /* The maximum die temp is specified by the Temperature Grade */
 414         switch ((val >> 6) & 0x3) {
 415         case 0: /* Commercial (0 to 95C) */
 416                 data->temp_grade = "Commercial";
 417                 data->temp_max = 95000;
 418                 break;
 419         case 1: /* Extended Commercial (-20 to 105C) */
 420                 data->temp_grade = "Extended Commercial";
 421                 data->temp_max = 105000;
 422                 break;
 423         case 2: /* Industrial (-40 to 105C) */
 424                 data->temp_grade = "Industrial";
 425                 data->temp_max = 105000;
 426                 break;
 427         case 3: /* Automotive (-40 to 125C) */
 428                 data->temp_grade = "Automotive";
 429                 data->temp_max = 125000;
 430                 break;
 431         }
 432
 433         /*
 434          * Set the critical trip point at 5C under max
 435          * Set the passive trip point at 10C under max (can change via sysfs)
 436          */
 437         data->temp_critical = data->temp_max - (1000 * 5);
 438         data->temp_passive = data->temp_max - (1000 * 10);
 439
 440         return 0;
 441 }
 442
 443 static irqreturn_t imx_thermal_alarm_irq(int irq, void *dev)
 444 {
 445         struct imx_thermal_data *data = dev;
 446
 447         disable_irq_nosync(irq);
 448         data->irq_enabled = false;
 449
 450         return IRQ_WAKE_THREAD;
 451 }
 452
 453 static irqreturn_t imx_thermal_alarm_irq_thread(int irq, void *dev)
 454 {
 455         struct imx_thermal_data *data = dev;
 456
 457         dev_dbg(&data->tz->device, "THERMAL ALARM: T > %d\n",
 458                 data->alarm_temp / 1000);
 459
 460         thermal_zone_device_update(data->tz);
 461
 462         return IRQ_HANDLED;
 463 }
 464
 465 static const struct of_device_id of_imx_thermal_match[] = {
 466         { .compatible = "fsl,imx6q-tempmon", .data = &thermal_imx6q_data, },
 467         { .compatible = "fsl,imx6sx-tempmon", .data = &thermal_imx6sx_data, },
 468         { /* end */ }
 469 };
 470 MODULE_DEVICE_TABLE(of, of_imx_thermal_match);
 471
 472 static int imx_thermal_probe(struct platform_device *pdev)
 473 {
 474         const struct of_device_id *of_id =
 475                 of_match_device(of_imx_thermal_match, &pdev->dev);
 476         struct imx_thermal_data *data;
 477         struct regmap *map;
 478         int measure_freq;
 479         int ret;
 480
 481         data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
 482         if (!data)
 483                 return -ENOMEM;
 484
 485         map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "fsl,tempmon");
 486         if (IS_ERR(map)) {
 487                 ret = PTR_ERR(map);
 488                 dev_err(&pdev->dev, "failed to get tempmon regmap: %d\n", ret);
 489                 return ret;
 490         }
 491         data->tempmon = map;
 492
 493         data->socdata = of_id->data;
 494
 495         /* make sure the IRQ flag is clear before enabling irq on i.MX6SX */
 496         if (data->socdata->version == TEMPMON_IMX6SX) {
 497                 regmap_write(map, MISC1 + REG_CLR, MISC1_IRQ_TEMPHIGH |
 498                         MISC1_IRQ_TEMPLOW | MISC1_IRQ_TEMPPANIC);
 499                 /*
 500                  * reset value of LOW ALARM is incorrect, set it to lowest
 501                  * value to avoid false trigger of low alarm.
 502                  */
 503                 regmap_write(map, TEMPSENSE2 + REG_SET,
 504                         TEMPSENSE2_LOW_VALUE_MASK);
 505         }
 506
 507         data->irq = platform_get_irq(pdev, 0);
 508         if (data->irq < 0)
 509                 return data->irq;
 510
 511         platform_set_drvdata(pdev, data);
 512
 513         ret = imx_get_sensor_data(pdev);
 514         if (ret) {
 515                 dev_err(&pdev->dev, "failed to get sensor data\n");
 516                 return ret;
 517         }
 518
 519         /* Make sure sensor is in known good state for measurements */
 520         regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
 521         regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
 522         regmap_write(map, TEMPSENSE1 + REG_CLR, TEMPSENSE1_MEASURE_FREQ);
 523         regmap_write(map, MISC0 + REG_SET, MISC0_REFTOP_SELBIASOFF);
 524         regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
 525
 526         data->cdev = cpufreq_cooling_register(cpu_present_mask);
 527         if (IS_ERR(data->cdev)) {
 528                 ret = PTR_ERR(data->cdev);
 529                 if (ret != -EPROBE_DEFER)
 530                         dev_err(&pdev->dev,
 531                                 "failed to register cpufreq cooling device: %d\n",
 532                                 ret);
 533                 return ret;
 534         }
 535
 536         data->thermal_clk = devm_clk_get(&pdev->dev, NULL);
 537         if (IS_ERR(data->thermal_clk)) {
 538                 ret = PTR_ERR(data->thermal_clk);
 539                 if (ret != -EPROBE_DEFER)
 540                         dev_err(&pdev->dev,
 541                                 "failed to get thermal clk: %d\n", ret);
 542                 cpufreq_cooling_unregister(data->cdev);
 543                 return ret;
 544         }
 545
 546         /*
 547          * Thermal sensor needs clk on to get correct value, normally
 548          * we should enable its clk before taking measurement and disable
 549          * clk after measurement is done, but if alarm function is enabled,
 550          * hardware will auto measure the temperature periodically, so we
 551          * need to keep the clk always on for alarm function.
 552          */
 553         ret = clk_prepare_enable(data->thermal_clk);
 554         if (ret) {
 555                 dev_err(&pdev->dev, "failed to enable thermal clk: %d\n", ret);
 556                 cpufreq_cooling_unregister(data->cdev);
 557                 return ret;
 558         }
 559
 560         data->tz = thermal_zone_device_register("imx_thermal_zone",
 561                                                 IMX_TRIP_NUM,
 562                                                 BIT(IMX_TRIP_PASSIVE), data,
 563                                                 &imx_tz_ops, NULL,
 564                                                 IMX_PASSIVE_DELAY,
 565                                                 IMX_POLLING_DELAY);
 566         if (IS_ERR(data->tz)) {
 567                 ret = PTR_ERR(data->tz);
 568                 dev_err(&pdev->dev,
 569                         "failed to register thermal zone device %d\n", ret);
 570                 clk_disable_unprepare(data->thermal_clk);
 571                 cpufreq_cooling_unregister(data->cdev);
 572                 return ret;
 573         }
 574
 575         dev_info(&pdev->dev, "%s CPU temperature grade - max:%dC"
 576                  " critical:%dC passive:%dC\n", data->temp_grade,
 577                  data->temp_max / 1000, data->temp_critical / 1000,
 578                  data->temp_passive / 1000);
 579
 580         /* Enable measurements at ~ 10 Hz */
 581         regmap_write(map, TEMPSENSE1 + REG_CLR, TEMPSENSE1_MEASURE_FREQ);
 582         measure_freq = DIV_ROUND_UP(32768, 10); /* 10 Hz */
 583         regmap_write(map, TEMPSENSE1 + REG_SET, measure_freq);
 584         imx_set_alarm_temp(data, data->temp_passive);
 585
 586         if (data->socdata->version == TEMPMON_IMX6SX)
 587                 imx_set_panic_temp(data, data->temp_critical);
 588
 589         regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
 590         regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
 591
 592         ret = devm_request_threaded_irq(&pdev->dev, data->irq,
 593                         imx_thermal_alarm_irq, imx_thermal_alarm_irq_thread,
 594                         0, "imx_thermal", data);
 595         if (ret < 0) {
 596                 dev_err(&pdev->dev, "failed to request alarm irq: %d\n", ret);
 597                 clk_disable_unprepare(data->thermal_clk);
 598                 thermal_zone_device_unregister(data->tz);
 599                 cpufreq_cooling_unregister(data->cdev);
 600                 return ret;
 601         }
 602
 603         data->irq_enabled = true;
 604         data->mode = THERMAL_DEVICE_ENABLED;
 605
 606         return 0;
 607 }
 608
 609 static int imx_thermal_remove(struct platform_device *pdev)
 610 {
 611         struct imx_thermal_data *data = platform_get_drvdata(pdev);
 612         struct regmap *map = data->tempmon;
 613
 614         /* Disable measurements */
 615         regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
 616         if (!IS_ERR(data->thermal_clk))
 617                 clk_disable_unprepare(data->thermal_clk);
 618
 619         thermal_zone_device_unregister(data->tz);
 620         cpufreq_cooling_unregister(data->cdev);
 621
 622         return 0;
 623 }
 624
 625 #ifdef CONFIG_PM_SLEEP
 626 static int imx_thermal_suspend(struct device *dev)
 627 {
 628         struct imx_thermal_data *data = dev_get_drvdata(dev);
 629         struct regmap *map = data->tempmon;
 630
 631         /*
 632          * Need to disable thermal sensor, otherwise, when thermal core
 633          * try to get temperature before thermal sensor resume, a wrong
 634          * temperature will be read as the thermal sensor is powered
 635          * down.
 636          */
 637         regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
 638         regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
 639         data->mode = THERMAL_DEVICE_DISABLED;
 640         clk_disable_unprepare(data->thermal_clk);
 641
 642         return 0;
 643 }
 644
 645 static int imx_thermal_resume(struct device *dev)
 646 {
 647         struct imx_thermal_data *data = dev_get_drvdata(dev);
 648         struct regmap *map = data->tempmon;
 649
 650         clk_prepare_enable(data->thermal_clk);
 651         /* Enabled thermal sensor after resume */
 652         regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
 653         regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
 654         data->mode = THERMAL_DEVICE_ENABLED;
 655
 656         return 0;
 657 }
 658 #endif
 659
 660 static SIMPLE_DEV_PM_OPS(imx_thermal_pm_ops,
 661                          imx_thermal_suspend, imx_thermal_resume);
 662
 663 static struct platform_driver imx_thermal = {
 664         .driver = {
 665                 .name   = "imx_thermal",
 666                 .pm     = &imx_thermal_pm_ops,
 667                 .of_match_table = of_imx_thermal_match,
 668         },
 669         .probe          = imx_thermal_probe,
 670         .remove         = imx_thermal_remove,
 671 };
 672 module_platform_driver(imx_thermal);
 673
 674 MODULE_AUTHOR("Freescale Semiconductor, Inc.");
 675 MODULE_DESCRIPTION("Thermal driver for Freescale i.MX SoCs");
 676 MODULE_LICENSE("GPL v2");
 677 MODULE_ALIAS("platform:imx-thermal");