root/drivers/thermal/qcom/qcom-spmi-temp-alarm.c

DEFINITIONS

1. qpnp_tm_read
2. qpnp_tm_write
3. qpnp_tm_get_temp_stage
4. qpnp_tm_update_temp_no_adc
5. qpnp_tm_get_temp
6. qpnp_tm_update_critical_trip_temp
7. qpnp_tm_set_trip_temp
8. qpnp_tm_isr
9. qpnp_tm_get_critical_trip_temp
10. qpnp_tm_init
11. qpnp_tm_probe

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2011-2015, 2017, The Linux Foundation. All rights reserved.
   4  */
   5 
   6 #include <linux/bitops.h>
   7 #include <linux/delay.h>
   8 #include <linux/err.h>
   9 #include <linux/iio/consumer.h>
  10 #include <linux/interrupt.h>
  11 #include <linux/module.h>
  12 #include <linux/of.h>
  13 #include <linux/of_device.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/regmap.h>
  16 #include <linux/thermal.h>
  17 
  18 #include "../thermal_core.h"
  19 
  20 #define QPNP_TM_REG_TYPE                0x04
  21 #define QPNP_TM_REG_SUBTYPE             0x05
  22 #define QPNP_TM_REG_STATUS              0x08
  23 #define QPNP_TM_REG_SHUTDOWN_CTRL1      0x40
  24 #define QPNP_TM_REG_ALARM_CTRL          0x46
  25 
  26 #define QPNP_TM_TYPE                    0x09
  27 #define QPNP_TM_SUBTYPE_GEN1            0x08
  28 #define QPNP_TM_SUBTYPE_GEN2            0x09
  29 
  30 #define STATUS_GEN1_STAGE_MASK          GENMASK(1, 0)
  31 #define STATUS_GEN2_STATE_MASK          GENMASK(6, 4)
  32 #define STATUS_GEN2_STATE_SHIFT         4
  33 
  34 #define SHUTDOWN_CTRL1_OVERRIDE_S2      BIT(6)
  35 #define SHUTDOWN_CTRL1_THRESHOLD_MASK   GENMASK(1, 0)
  36 
  37 #define SHUTDOWN_CTRL1_RATE_25HZ        BIT(3)
  38 
  39 #define ALARM_CTRL_FORCE_ENABLE         BIT(7)
  40 
  41 /*
  42  * Trip point values based on threshold control
  43  * 0 = {105 C, 125 C, 145 C}
  44  * 1 = {110 C, 130 C, 150 C}
  45  * 2 = {115 C, 135 C, 155 C}
  46  * 3 = {120 C, 140 C, 160 C}
  47 */
  48 #define TEMP_STAGE_STEP                 20000   /* Stage step: 20.000 C */
  49 #define TEMP_STAGE_HYSTERESIS           2000
  50 
  51 #define TEMP_THRESH_MIN                 105000  /* Threshold Min: 105 C */
  52 #define TEMP_THRESH_STEP                5000    /* Threshold step: 5 C */
  53 
  54 #define THRESH_MIN                      0
  55 #define THRESH_MAX                      3
  56 
  57 /* Stage 2 Threshold Min: 125 C */
  58 #define STAGE2_THRESHOLD_MIN            125000
  59 /* Stage 2 Threshold Max: 140 C */
  60 #define STAGE2_THRESHOLD_MAX            140000
  61 
  62 /* Temperature in Milli Celsius reported during stage 0 if no ADC is present */
  63 #define DEFAULT_TEMP                    37000
  64 
  65 struct qpnp_tm_chip {
  66         struct regmap                   *map;
  67         struct device                   *dev;
  68         struct thermal_zone_device      *tz_dev;
  69         unsigned int                    subtype;
  70         long                            temp;
  71         unsigned int                    thresh;
  72         unsigned int                    stage;
  73         unsigned int                    prev_stage;
  74         unsigned int                    base;
  75         /* protects .thresh, .stage and chip registers */
  76         struct mutex                    lock;
  77         bool                            initialized;
  78 
  79         struct iio_channel              *adc;
  80 };
  81 
  82 /* This array maps from GEN2 alarm state to GEN1 alarm stage */
  83 static const unsigned int alarm_state_map[8] = {0, 1, 1, 2, 2, 3, 3, 3};
  84 
  85 static int qpnp_tm_read(struct qpnp_tm_chip *chip, u16 addr, u8 *data)
  86 {
  87         unsigned int val;
  88         int ret;
  89 
  90         ret = regmap_read(chip->map, chip->base + addr, &val);
  91         if (ret < 0)
  92                 return ret;
  93 
  94         *data = val;
  95         return 0;
  96 }
  97 
  98 static int qpnp_tm_write(struct qpnp_tm_chip *chip, u16 addr, u8 data)
  99 {
 100         return regmap_write(chip->map, chip->base + addr, data);
 101 }
 102 
 103 /**
 104  * qpnp_tm_get_temp_stage() - return over-temperature stage
 105  * @chip:               Pointer to the qpnp_tm chip
 106  *
 107  * Return: stage (GEN1) or state (GEN2) on success, or errno on failure.
 108  */
 109 static int qpnp_tm_get_temp_stage(struct qpnp_tm_chip *chip)
 110 {
 111         int ret;
 112         u8 reg = 0;
 113 
 114         ret = qpnp_tm_read(chip, QPNP_TM_REG_STATUS, &reg);
 115         if (ret < 0)
 116                 return ret;
 117 
 118         if (chip->subtype == QPNP_TM_SUBTYPE_GEN1)
 119                 ret = reg & STATUS_GEN1_STAGE_MASK;
 120         else
 121                 ret = (reg & STATUS_GEN2_STATE_MASK) >> STATUS_GEN2_STATE_SHIFT;
 122 
 123         return ret;
 124 }
 125 
 126 /*
 127  * This function updates the internal temp value based on the
 128  * current thermal stage and threshold as well as the previous stage
 129  */
 130 static int qpnp_tm_update_temp_no_adc(struct qpnp_tm_chip *chip)
 131 {
 132         unsigned int stage, stage_new, stage_old;
 133         int ret;
 134 
 135         WARN_ON(!mutex_is_locked(&chip->lock));
 136 
 137         ret = qpnp_tm_get_temp_stage(chip);
 138         if (ret < 0)
 139                 return ret;
 140         stage = ret;
 141 
 142         if (chip->subtype == QPNP_TM_SUBTYPE_GEN1) {
 143                 stage_new = stage;
 144                 stage_old = chip->stage;
 145         } else {
 146                 stage_new = alarm_state_map[stage];
 147                 stage_old = alarm_state_map[chip->stage];
 148         }
 149 
 150         if (stage_new > stage_old) {
 151                 /* increasing stage, use lower bound */
 152                 chip->temp = (stage_new - 1) * TEMP_STAGE_STEP +
 153                              chip->thresh * TEMP_THRESH_STEP +
 154                              TEMP_STAGE_HYSTERESIS + TEMP_THRESH_MIN;
 155         } else if (stage_new < stage_old) {
 156                 /* decreasing stage, use upper bound */
 157                 chip->temp = stage_new * TEMP_STAGE_STEP +
 158                              chip->thresh * TEMP_THRESH_STEP -
 159                              TEMP_STAGE_HYSTERESIS + TEMP_THRESH_MIN;
 160         }
 161 
 162         chip->stage = stage;
 163 
 164         return 0;
 165 }
 166 
 167 static int qpnp_tm_get_temp(void *data, int *temp)
 168 {
 169         struct qpnp_tm_chip *chip = data;
 170         int ret, mili_celsius;
 171 
 172         if (!temp)
 173                 return -EINVAL;
 174 
 175         if (!chip->initialized) {
 176                 *temp = DEFAULT_TEMP;
 177                 return 0;
 178         }
 179 
 180         if (!chip->adc) {
 181                 mutex_lock(&chip->lock);
 182                 ret = qpnp_tm_update_temp_no_adc(chip);
 183                 mutex_unlock(&chip->lock);
 184                 if (ret < 0)
 185                         return ret;
 186         } else {
 187                 ret = iio_read_channel_processed(chip->adc, &mili_celsius);
 188                 if (ret < 0)
 189                         return ret;
 190 
 191                 chip->temp = mili_celsius;
 192         }
 193 
 194         *temp = chip->temp < 0 ? 0 : chip->temp;
 195 
 196         return 0;
 197 }
 198 
 199 static int qpnp_tm_update_critical_trip_temp(struct qpnp_tm_chip *chip,
 200                                              int temp)
 201 {
 202         u8 reg;
 203         bool disable_s2_shutdown = false;
 204 
 205         WARN_ON(!mutex_is_locked(&chip->lock));
 206 
 207         /*
 208          * Default: S2 and S3 shutdown enabled, thresholds at
 209          * 105C/125C/145C, monitoring at 25Hz
 210          */
 211         reg = SHUTDOWN_CTRL1_RATE_25HZ;
 212 
 213         if (temp == THERMAL_TEMP_INVALID ||
 214             temp < STAGE2_THRESHOLD_MIN) {
 215                 chip->thresh = THRESH_MIN;
 216                 goto skip;
 217         }
 218 
 219         if (temp <= STAGE2_THRESHOLD_MAX) {
 220                 chip->thresh = THRESH_MAX -
 221                         ((STAGE2_THRESHOLD_MAX - temp) /
 222                          TEMP_THRESH_STEP);
 223                 disable_s2_shutdown = true;
 224         } else {
 225                 chip->thresh = THRESH_MAX;
 226 
 227                 if (chip->adc)
 228                         disable_s2_shutdown = true;
 229                 else
 230                         dev_warn(chip->dev,
 231                                  "No ADC is configured and critical temperature is above the maximum stage 2 threshold of 140 C! Configuring stage 2 shutdown at 140 C.\n");
 232         }
 233 
 234 skip:
 235         reg |= chip->thresh;
 236         if (disable_s2_shutdown)
 237                 reg |= SHUTDOWN_CTRL1_OVERRIDE_S2;
 238 
 239         return qpnp_tm_write(chip, QPNP_TM_REG_SHUTDOWN_CTRL1, reg);
 240 }
 241 
 242 static int qpnp_tm_set_trip_temp(void *data, int trip, int temp)
 243 {
 244         struct qpnp_tm_chip *chip = data;
 245         const struct thermal_trip *trip_points;
 246         int ret;
 247 
 248         trip_points = of_thermal_get_trip_points(chip->tz_dev);
 249         if (!trip_points)
 250                 return -EINVAL;
 251 
 252         if (trip_points[trip].type != THERMAL_TRIP_CRITICAL)
 253                 return 0;
 254 
 255         mutex_lock(&chip->lock);
 256         ret = qpnp_tm_update_critical_trip_temp(chip, temp);
 257         mutex_unlock(&chip->lock);
 258 
 259         return ret;
 260 }
 261 
 262 static const struct thermal_zone_of_device_ops qpnp_tm_sensor_ops = {
 263         .get_temp = qpnp_tm_get_temp,
 264         .set_trip_temp = qpnp_tm_set_trip_temp,
 265 };
 266 
 267 static irqreturn_t qpnp_tm_isr(int irq, void *data)
 268 {
 269         struct qpnp_tm_chip *chip = data;
 270 
 271         thermal_zone_device_update(chip->tz_dev, THERMAL_EVENT_UNSPECIFIED);
 272 
 273         return IRQ_HANDLED;
 274 }
 275 
 276 static int qpnp_tm_get_critical_trip_temp(struct qpnp_tm_chip *chip)
 277 {
 278         int ntrips;
 279         const struct thermal_trip *trips;
 280         int i;
 281 
 282         ntrips = of_thermal_get_ntrips(chip->tz_dev);
 283         if (ntrips <= 0)
 284                 return THERMAL_TEMP_INVALID;
 285 
 286         trips = of_thermal_get_trip_points(chip->tz_dev);
 287         if (!trips)
 288                 return THERMAL_TEMP_INVALID;
 289 
 290         for (i = 0; i < ntrips; i++) {
 291                 if (of_thermal_is_trip_valid(chip->tz_dev, i) &&
 292                     trips[i].type == THERMAL_TRIP_CRITICAL)
 293                         return trips[i].temperature;
 294         }
 295 
 296         return THERMAL_TEMP_INVALID;
 297 }
 298 
 299 /*
 300  * This function initializes the internal temp value based on only the
 301  * current thermal stage and threshold. Setup threshold control and
 302  * disable shutdown override.
 303  */
 304 static int qpnp_tm_init(struct qpnp_tm_chip *chip)
 305 {
 306         unsigned int stage;
 307         int ret;
 308         u8 reg = 0;
 309         int crit_temp;
 310 
 311         mutex_lock(&chip->lock);
 312 
 313         ret = qpnp_tm_read(chip, QPNP_TM_REG_SHUTDOWN_CTRL1, &reg);
 314         if (ret < 0)
 315                 goto out;
 316 
 317         chip->thresh = reg & SHUTDOWN_CTRL1_THRESHOLD_MASK;
 318         chip->temp = DEFAULT_TEMP;
 319 
 320         ret = qpnp_tm_get_temp_stage(chip);
 321         if (ret < 0)
 322                 goto out;
 323         chip->stage = ret;
 324 
 325         stage = chip->subtype == QPNP_TM_SUBTYPE_GEN1
 326                 ? chip->stage : alarm_state_map[chip->stage];
 327 
 328         if (stage)
 329                 chip->temp = chip->thresh * TEMP_THRESH_STEP +
 330                              (stage - 1) * TEMP_STAGE_STEP +
 331                              TEMP_THRESH_MIN;
 332 
 333         crit_temp = qpnp_tm_get_critical_trip_temp(chip);
 334         ret = qpnp_tm_update_critical_trip_temp(chip, crit_temp);
 335         if (ret < 0)
 336                 goto out;
 337 
 338         /* Enable the thermal alarm PMIC module in always-on mode. */
 339         reg = ALARM_CTRL_FORCE_ENABLE;
 340         ret = qpnp_tm_write(chip, QPNP_TM_REG_ALARM_CTRL, reg);
 341 
 342         chip->initialized = true;
 343 
 344 out:
 345         mutex_unlock(&chip->lock);
 346         return ret;
 347 }
 348 
 349 static int qpnp_tm_probe(struct platform_device *pdev)
 350 {
 351         struct qpnp_tm_chip *chip;
 352         struct device_node *node;
 353         u8 type, subtype;
 354         u32 res;
 355         int ret, irq;
 356 
 357         node = pdev->dev.of_node;
 358 
 359         chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
 360         if (!chip)
 361                 return -ENOMEM;
 362 
 363         dev_set_drvdata(&pdev->dev, chip);
 364         chip->dev = &pdev->dev;
 365 
 366         mutex_init(&chip->lock);
 367 
 368         chip->map = dev_get_regmap(pdev->dev.parent, NULL);
 369         if (!chip->map)
 370                 return -ENXIO;
 371 
 372         ret = of_property_read_u32(node, "reg", &res);
 373         if (ret < 0)
 374                 return ret;
 375 
 376         irq = platform_get_irq(pdev, 0);
 377         if (irq < 0)
 378                 return irq;
 379 
 380         /* ADC based measurements are optional */
 381         chip->adc = devm_iio_channel_get(&pdev->dev, "thermal");
 382         if (IS_ERR(chip->adc)) {
 383                 ret = PTR_ERR(chip->adc);
 384                 chip->adc = NULL;
 385                 if (ret == -EPROBE_DEFER)
 386                         return ret;
 387         }
 388 
 389         chip->base = res;
 390 
 391         ret = qpnp_tm_read(chip, QPNP_TM_REG_TYPE, &type);
 392         if (ret < 0) {
 393                 dev_err(&pdev->dev, "could not read type\n");
 394                 return ret;
 395         }
 396 
 397         ret = qpnp_tm_read(chip, QPNP_TM_REG_SUBTYPE, &subtype);
 398         if (ret < 0) {
 399                 dev_err(&pdev->dev, "could not read subtype\n");
 400                 return ret;
 401         }
 402 
 403         if (type != QPNP_TM_TYPE || (subtype != QPNP_TM_SUBTYPE_GEN1
 404                                      && subtype != QPNP_TM_SUBTYPE_GEN2)) {
 405                 dev_err(&pdev->dev, "invalid type 0x%02x or subtype 0x%02x\n",
 406                         type, subtype);
 407                 return -ENODEV;
 408         }
 409 
 410         chip->subtype = subtype;
 411 
 412         /*
 413          * Register the sensor before initializing the hardware to be able to
 414          * read the trip points. get_temp() returns the default temperature
 415          * before the hardware initialization is completed.
 416          */
 417         chip->tz_dev = devm_thermal_zone_of_sensor_register(
 418                 &pdev->dev, 0, chip, &qpnp_tm_sensor_ops);
 419         if (IS_ERR(chip->tz_dev)) {
 420                 dev_err(&pdev->dev, "failed to register sensor\n");
 421                 return PTR_ERR(chip->tz_dev);
 422         }
 423 
 424         ret = qpnp_tm_init(chip);
 425         if (ret < 0) {
 426                 dev_err(&pdev->dev, "init failed\n");
 427                 return ret;
 428         }
 429 
 430         ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, qpnp_tm_isr,
 431                                         IRQF_ONESHOT, node->name, chip);
 432         if (ret < 0)
 433                 return ret;
 434 
 435         thermal_zone_device_update(chip->tz_dev, THERMAL_EVENT_UNSPECIFIED);
 436 
 437         return 0;
 438 }
 439 
 440 static const struct of_device_id qpnp_tm_match_table[] = {
 441         { .compatible = "qcom,spmi-temp-alarm" },
 442         { }
 443 };
 444 MODULE_DEVICE_TABLE(of, qpnp_tm_match_table);
 445 
 446 static struct platform_driver qpnp_tm_driver = {
 447         .driver = {
 448                 .name = "spmi-temp-alarm",
 449                 .of_match_table = qpnp_tm_match_table,
 450         },
 451         .probe  = qpnp_tm_probe,
 452 };
 453 module_platform_driver(qpnp_tm_driver);
 454 
 455 MODULE_ALIAS("platform:spmi-temp-alarm");
 456 MODULE_DESCRIPTION("QPNP PMIC Temperature Alarm driver");
 457 MODULE_LICENSE("GPL v2");