| 1 | |
| 2 | |
| 3 | * STTS751 sensor driver
|
| 4 | *
|
| 5 | * Copyright (C) 2016-2017 Istituto Italiano di Tecnologia - RBCS - EDL
|
| 6 | * Robotics, Brain and Cognitive Sciences department
|
| 7 | * Electronic Design Laboratory
|
| 8 | *
|
| 9 | * Written by Andrea Merello <[email protected]>
|
| 10 | *
|
| 11 | * Based on LM95241 driver and LM90 driver
|
| 12 |
|
| 13 |
|
| 14 | #include <linux/bitops.h>
|
| 15 | #include <linux/err.h>
|
| 16 | #include <linux/hwmon.h>
|
| 17 | #include <linux/hwmon-sysfs.h>
|
| 18 | #include <linux/i2c.h>
|
| 19 | #include <linux/init.h>
|
| 20 | #include <linux/interrupt.h>
|
| 21 | #include <linux/jiffies.h>
|
| 22 | #include <linux/module.h>
|
| 23 | #include <linux/mutex.h>
|
| 24 | #include <linux/property.h>
|
| 25 | #include <linux/slab.h>
|
| 26 | #include <linux/sysfs.h>
|
| 27 | #include <linux/util_macros.h>
|
| 28 |
|
| 29 | #define DEVNAME "stts751"
|
| 30 |
|
| 31 | static const unsigned short normal_i2c[] = {
|
| 32 | 0x48, 0x49, 0x38, 0x39,
|
| 33 | 0x4A, 0x4B, 0x3A, 0x3B,
|
| 34 | I2C_CLIENT_END };
|
| 35 |
|
| 36 | #define STTS751_REG_TEMP_H 0x00
|
| 37 | #define STTS751_REG_STATUS 0x01
|
| 38 | #define STTS751_STATUS_TRIPT BIT(0)
|
| 39 | #define STTS751_STATUS_TRIPL BIT(5)
|
| 40 | #define STTS751_STATUS_TRIPH BIT(6)
|
| 41 | #define STTS751_REG_TEMP_L 0x02
|
| 42 | #define STTS751_REG_CONF 0x03
|
| 43 | #define STTS751_CONF_RES_MASK 0x0C
|
| 44 | #define STTS751_CONF_RES_SHIFT 2
|
| 45 | #define STTS751_CONF_EVENT_DIS BIT(7)
|
| 46 | #define STTS751_CONF_STOP BIT(6)
|
| 47 | #define STTS751_REG_RATE 0x04
|
| 48 | #define STTS751_REG_HLIM_H 0x05
|
| 49 | #define STTS751_REG_HLIM_L 0x06
|
| 50 | #define STTS751_REG_LLIM_H 0x07
|
| 51 | #define STTS751_REG_LLIM_L 0x08
|
| 52 | #define STTS751_REG_TLIM 0x20
|
| 53 | #define STTS751_REG_HYST 0x21
|
| 54 | #define STTS751_REG_SMBUS_TO 0x22
|
| 55 |
|
| 56 | #define STTS751_REG_PROD_ID 0xFD
|
| 57 | #define STTS751_REG_MAN_ID 0xFE
|
| 58 | #define STTS751_REG_REV_ID 0xFF
|
| 59 |
|
| 60 | #define STTS751_0_PROD_ID 0x00
|
| 61 | #define STTS751_1_PROD_ID 0x01
|
| 62 | #define ST_MAN_ID 0x53
|
| 63 |
|
| 64 | |
| 65 | * Possible update intervals are (in mS):
|
| 66 | * 16000, 8000, 4000, 2000, 1000, 500, 250, 125, 62.5, 31.25
|
| 67 | * However we are not going to complicate things too much and we stick to the
|
| 68 | * approx value in mS.
|
| 69 |
|
| 70 | static const int stts751_intervals[] = {
|
| 71 | 16000, 8000, 4000, 2000, 1000, 500, 250, 125, 63, 31
|
| 72 | };
|
| 73 |
|
| 74 | static const struct i2c_device_id stts751_id[] = {
|
| 75 | { .name = "stts751" },
|
| 76 | { }
|
| 77 | };
|
| 78 |
|
| 79 | static const struct of_device_id __maybe_unused stts751_of_match[] = {
|
| 80 | { .compatible = "st,stts751" },
|
| 81 | { },
|
| 82 | };
|
| 83 | MODULE_DEVICE_TABLE(of, stts751_of_match);
|
| 84 |
|
| 85 | struct stts751_priv {
|
| 86 | struct device *dev;
|
| 87 | struct i2c_client *client;
|
| 88 | struct mutex access_lock;
|
| 89 | u8 interval;
|
| 90 | int res;
|
| 91 | int event_max, event_min;
|
| 92 | int therm;
|
| 93 | int hyst;
|
| 94 | int temp;
|
| 95 | unsigned long last_update, last_alert_update;
|
| 96 | u8 config;
|
| 97 | bool min_alert, max_alert, therm_trip;
|
| 98 | bool data_valid, alert_valid;
|
| 99 | bool notify_max, notify_min;
|
| 100 | };
|
| 101 |
|
| 102 | |
| 103 | * These functions converts temperature from HW format to integer format and
|
| 104 | * vice-vers. They are (mostly) taken from lm90 driver. Unit is in mC.
|
| 105 |
|
| 106 | static int stts751_to_deg(s16 hw_val)
|
| 107 | {
|
| 108 | return hw_val * 125 / 32;
|
| 109 | }
|
| 110 |
|
| 111 | static s32 stts751_to_hw(int val)
|
| 112 | {
|
| 113 | return DIV_ROUND_CLOSEST(val, 125) * 32;
|
| 114 | }
|
| 115 |
|
| 116 | static int stts751_adjust_resolution(struct stts751_priv *priv)
|
| 117 | {
|
| 118 | u8 res;
|
| 119 |
|
| 120 | switch (priv->interval) {
|
| 121 | case 9:
|
| 122 |
|
| 123 | res = 0;
|
| 124 | break;
|
| 125 | case 8:
|
| 126 |
|
| 127 | res = 1;
|
| 128 | break;
|
| 129 | default:
|
| 130 |
|
| 131 | res = 3;
|
| 132 | break;
|
| 133 | }
|
| 134 |
|
| 135 | if (priv->res == res)
|
| 136 | return 0;
|
| 137 |
|
| 138 | priv->config &= ~STTS751_CONF_RES_MASK;
|
| 139 | priv->config |= res << STTS751_CONF_RES_SHIFT;
|
| 140 | dev_dbg(&priv->client->dev, "setting res %d. config %x",
|
| 141 | res, priv->config);
|
| 142 | priv->res = res;
|
| 143 |
|
| 144 | return i2c_smbus_write_byte_data(priv->client,
|
| 145 | STTS751_REG_CONF, priv->config);
|
| 146 | }
|
| 147 |
|
| 148 | static int stts751_update_temp(struct stts751_priv *priv)
|
| 149 | {
|
| 150 | s32 integer1, integer2, frac;
|
| 151 |
|
| 152 | |
| 153 | * There is a trick here, like in the lm90 driver. We have to read two
|
| 154 | * registers to get the sensor temperature, but we have to beware a
|
| 155 | * conversion could occur between the readings. We could use the
|
| 156 | * one-shot conversion register, but we don't want to do this (disables
|
| 157 | * hardware monitoring). So the solution used here is to read the high
|
| 158 | * byte once, then the low byte, then the high byte again. If the new
|
| 159 | * high byte matches the old one, then we have a valid reading. Else we
|
| 160 | * have to read the low byte again, and now we believe we have a correct
|
| 161 | * reading.
|
| 162 |
|
| 163 | integer1 = i2c_smbus_read_byte_data(priv->client, STTS751_REG_TEMP_H);
|
| 164 | if (integer1 < 0) {
|
| 165 | dev_dbg(&priv->client->dev,
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| 166 | "I2C read failed (temp H). ret: %x\n", integer1);
|
| 167 | return integer1;
|
| 168 | }
|
| 169 |
|
| 170 | frac = i2c_smbus_read_byte_data(priv->client, STTS751_REG_TEMP_L);
|
| 171 | if (frac < 0) {
|
| 172 | dev_dbg(&priv->client->dev,
|
| 173 | "I2C read failed (temp L). ret: %x\n", frac);
|
| 174 | return frac;
|
| 175 | }
|
| 176 |
|
| 177 | integer2 = i2c_smbus_read_byte_data(priv->client, STTS751_REG_TEMP_H);
|
| 178 | if (integer2 < 0) {
|
| 179 | dev_dbg(&priv->client->dev,
|
| 180 | "I2C 2nd read failed (temp H). ret: %x\n", integer2);
|
| 181 | return integer2;
|
| 182 | }
|
| 183 |
|
| 184 | if (integer1 != integer2) {
|
| 185 | frac = i2c_smbus_read_byte_data(priv->client,
|
| 186 | STTS751_REG_TEMP_L);
|
| 187 | if (frac < 0) {
|
| 188 | dev_dbg(&priv->client->dev,
|
| 189 | "I2C 2nd read failed (temp L). ret: %x\n",
|
| 190 | frac);
|
| 191 | return frac;
|
| 192 | }
|
| 193 | }
|
| 194 |
|
| 195 | priv->temp = stts751_to_deg((integer1 << 8) | frac);
|
| 196 | return 0;
|
| 197 | }
|
| 198 |
|
| 199 | static int stts751_set_temp_reg16(struct stts751_priv *priv, int temp,
|
| 200 | u8 hreg, u8 lreg)
|
| 201 | {
|
| 202 | s32 hwval;
|
| 203 | int ret;
|
| 204 |
|
| 205 | hwval = stts751_to_hw(temp);
|
| 206 |
|
| 207 | ret = i2c_smbus_write_byte_data(priv->client, hreg, hwval >> 8);
|
| 208 | if (ret)
|
| 209 | return ret;
|
| 210 |
|
| 211 | return i2c_smbus_write_byte_data(priv->client, lreg, hwval & 0xff);
|
| 212 | }
|
| 213 |
|
| 214 | static int stts751_set_temp_reg8(struct stts751_priv *priv, int temp, u8 reg)
|
| 215 | {
|
| 216 | s32 hwval;
|
| 217 |
|
| 218 | hwval = stts751_to_hw(temp);
|
| 219 | return i2c_smbus_write_byte_data(priv->client, reg, hwval >> 8);
|
| 220 | }
|
| 221 |
|
| 222 | static int stts751_read_reg16(struct stts751_priv *priv, int *temp,
|
| 223 | u8 hreg, u8 lreg)
|
| 224 | {
|
| 225 | int integer, frac;
|
| 226 |
|
| 227 | integer = i2c_smbus_read_byte_data(priv->client, hreg);
|
| 228 | if (integer < 0)
|
| 229 | return integer;
|
| 230 |
|
| 231 | frac = i2c_smbus_read_byte_data(priv->client, lreg);
|
| 232 | if (frac < 0)
|
| 233 | return frac;
|
| 234 |
|
| 235 | *temp = stts751_to_deg((integer << 8) | frac);
|
| 236 |
|
| 237 | return 0;
|
| 238 | }
|
| 239 |
|
| 240 | static int stts751_read_reg8(struct stts751_priv *priv, int *temp, u8 reg)
|
| 241 | {
|
| 242 | int integer;
|
| 243 |
|
| 244 | integer = i2c_smbus_read_byte_data(priv->client, reg);
|
| 245 | if (integer < 0)
|
| 246 | return integer;
|
| 247 |
|
| 248 | *temp = stts751_to_deg(integer << 8);
|
| 249 |
|
| 250 | return 0;
|
| 251 | }
|
| 252 |
|
| 253 | |
| 254 | * Update alert flags without waiting for cache to expire. We detects alerts
|
| 255 | * immediately for the sake of the alert handler; we still need to deal with
|
| 256 | * caching to workaround the fact that alarm flags int the status register,
|
| 257 | * despite what the datasheet claims, gets always cleared on read.
|
| 258 |
|
| 259 | static int stts751_update_alert(struct stts751_priv *priv)
|
| 260 | {
|
| 261 | int ret;
|
| 262 | bool conv_done;
|
| 263 | int cache_time = msecs_to_jiffies(stts751_intervals[priv->interval]);
|
| 264 |
|
| 265 | |
| 266 | * Add another 10% because if we run faster than the HW conversion
|
| 267 | * rate we will end up in reporting incorrectly alarms.
|
| 268 |
|
| 269 | cache_time += cache_time / 10;
|
| 270 |
|
| 271 | ret = i2c_smbus_read_byte_data(priv->client, STTS751_REG_STATUS);
|
| 272 | if (ret < 0)
|
| 273 | return ret;
|
| 274 |
|
| 275 | dev_dbg(&priv->client->dev, "status reg %x\n", ret);
|
| 276 | conv_done = ret & (STTS751_STATUS_TRIPH | STTS751_STATUS_TRIPL);
|
| 277 | |
| 278 | * Reset the cache if the cache time expired, or if we are sure
|
| 279 | * we have valid data from a device conversion, or if we know
|
| 280 | * our cache has been never written.
|
| 281 | *
|
| 282 | * Note that when the cache has been never written the point is
|
| 283 | * to correctly initialize the timestamp, rather than clearing
|
| 284 | * the cache values.
|
| 285 | *
|
| 286 | * Note that updating the cache timestamp when we get an alarm flag
|
| 287 | * is required, otherwise we could incorrectly report alarms to be zero.
|
| 288 |
|
| 289 | if (time_after(jiffies, priv->last_alert_update + cache_time) ||
|
| 290 | conv_done || !priv->alert_valid) {
|
| 291 | priv->max_alert = false;
|
| 292 | priv->min_alert = false;
|
| 293 | priv->alert_valid = true;
|
| 294 | priv->last_alert_update = jiffies;
|
| 295 | dev_dbg(&priv->client->dev, "invalidating alert cache\n");
|
| 296 | }
|
| 297 |
|
| 298 | priv->max_alert |= !!(ret & STTS751_STATUS_TRIPH);
|
| 299 | priv->min_alert |= !!(ret & STTS751_STATUS_TRIPL);
|
| 300 | priv->therm_trip = !!(ret & STTS751_STATUS_TRIPT);
|
| 301 |
|
| 302 | dev_dbg(&priv->client->dev, "max_alert: %d, min_alert: %d, therm_trip: %d\n",
|
| 303 | priv->max_alert, priv->min_alert, priv->therm_trip);
|
| 304 |
|
| 305 | return 0;
|
| 306 | }
|
| 307 |
|
| 308 | static void stts751_alert(struct i2c_client *client,
|
| 309 | enum i2c_alert_protocol type, unsigned int data)
|
| 310 | {
|
| 311 | int ret;
|
| 312 | struct stts751_priv *priv = i2c_get_clientdata(client);
|
| 313 |
|
| 314 | if (type != I2C_PROTOCOL_SMBUS_ALERT)
|
| 315 | return;
|
| 316 |
|
| 317 | dev_dbg(&client->dev, "alert!");
|
| 318 |
|
| 319 | mutex_lock(&priv->access_lock);
|
| 320 | ret = stts751_update_alert(priv);
|
| 321 | if (ret < 0) {
|
| 322 |
|
| 323 | priv->max_alert = true;
|
| 324 | priv->min_alert = true;
|
| 325 |
|
| 326 | dev_warn(priv->dev,
|
| 327 | "Alert received, but can't communicate to the device. Triggering all alarms!");
|
| 328 | }
|
| 329 |
|
| 330 | if (priv->max_alert) {
|
| 331 | if (priv->notify_max)
|
| 332 | dev_notice(priv->dev, "got alert for HIGH temperature");
|
| 333 | priv->notify_max = false;
|
| 334 |
|
| 335 |
|
| 336 | sysfs_notify(&priv->dev->kobj, NULL, "temp1_max_alarm");
|
| 337 | }
|
| 338 |
|
| 339 | if (priv->min_alert) {
|
| 340 | if (priv->notify_min)
|
| 341 | dev_notice(priv->dev, "got alert for LOW temperature");
|
| 342 | priv->notify_min = false;
|
| 343 |
|
| 344 |
|
| 345 | sysfs_notify(&priv->dev->kobj, NULL, "temp1_min_alarm");
|
| 346 | }
|
| 347 |
|
| 348 | if (priv->min_alert || priv->max_alert)
|
| 349 | kobject_uevent(&priv->dev->kobj, KOBJ_CHANGE);
|
| 350 |
|
| 351 | mutex_unlock(&priv->access_lock);
|
| 352 | }
|
| 353 |
|
| 354 | static int stts751_update(struct stts751_priv *priv)
|
| 355 | {
|
| 356 | int ret;
|
| 357 | int cache_time = msecs_to_jiffies(stts751_intervals[priv->interval]);
|
| 358 |
|
| 359 | if (time_after(jiffies, priv->last_update + cache_time) ||
|
| 360 | !priv->data_valid) {
|
| 361 | ret = stts751_update_temp(priv);
|
| 362 | if (ret)
|
| 363 | return ret;
|
| 364 |
|
| 365 | ret = stts751_update_alert(priv);
|
| 366 | if (ret)
|
| 367 | return ret;
|
| 368 | priv->data_valid = true;
|
| 369 | priv->last_update = jiffies;
|
| 370 | }
|
| 371 |
|
| 372 | return 0;
|
| 373 | }
|
| 374 |
|
| 375 | static ssize_t max_alarm_show(struct device *dev,
|
| 376 | struct device_attribute *attr, char *buf)
|
| 377 | {
|
| 378 | int ret;
|
| 379 | struct stts751_priv *priv = dev_get_drvdata(dev);
|
| 380 |
|
| 381 | mutex_lock(&priv->access_lock);
|
| 382 | ret = stts751_update(priv);
|
| 383 | if (!ret)
|
| 384 | priv->notify_max = true;
|
| 385 | mutex_unlock(&priv->access_lock);
|
| 386 | if (ret < 0)
|
| 387 | return ret;
|
| 388 |
|
| 389 | return sysfs_emit(buf, "%d\n", priv->max_alert);
|
| 390 | }
|
| 391 |
|
| 392 | static ssize_t min_alarm_show(struct device *dev,
|
| 393 | struct device_attribute *attr, char *buf)
|
| 394 | {
|
| 395 | int ret;
|
| 396 | struct stts751_priv *priv = dev_get_drvdata(dev);
|
| 397 |
|
| 398 | mutex_lock(&priv->access_lock);
|
| 399 | ret = stts751_update(priv);
|
| 400 | if (!ret)
|
| 401 | priv->notify_min = true;
|
| 402 | mutex_unlock(&priv->access_lock);
|
| 403 | if (ret < 0)
|
| 404 | return ret;
|
| 405 |
|
| 406 | return sysfs_emit(buf, "%d\n", priv->min_alert);
|
| 407 | }
|
| 408 |
|
| 409 | static ssize_t input_show(struct device *dev, struct device_attribute *attr,
|
| 410 | char *buf)
|
| 411 | {
|
| 412 | int ret;
|
| 413 | struct stts751_priv *priv = dev_get_drvdata(dev);
|
| 414 |
|
| 415 | mutex_lock(&priv->access_lock);
|
| 416 | ret = stts751_update(priv);
|
| 417 | mutex_unlock(&priv->access_lock);
|
| 418 | if (ret < 0)
|
| 419 | return ret;
|
| 420 |
|
| 421 | return sysfs_emit(buf, "%d\n", priv->temp);
|
| 422 | }
|
| 423 |
|
| 424 | static ssize_t therm_show(struct device *dev, struct device_attribute *attr,
|
| 425 | char *buf)
|
| 426 | {
|
| 427 | struct stts751_priv *priv = dev_get_drvdata(dev);
|
| 428 |
|
| 429 | return sysfs_emit(buf, "%d\n", priv->therm);
|
| 430 | }
|
| 431 |
|
| 432 | static ssize_t therm_store(struct device *dev, struct device_attribute *attr,
|
| 433 | const char *buf, size_t count)
|
| 434 | {
|
| 435 | int ret;
|
| 436 | long temp;
|
| 437 | struct stts751_priv *priv = dev_get_drvdata(dev);
|
| 438 |
|
| 439 | if (kstrtol(buf, 10, &temp) < 0)
|
| 440 | return -EINVAL;
|
| 441 |
|
| 442 |
|
| 443 | temp = clamp_val(temp, -64000, 127937);
|
| 444 | mutex_lock(&priv->access_lock);
|
| 445 | ret = stts751_set_temp_reg8(priv, temp, STTS751_REG_TLIM);
|
| 446 | if (ret)
|
| 447 | goto exit;
|
| 448 |
|
| 449 | dev_dbg(&priv->client->dev, "setting therm %ld", temp);
|
| 450 |
|
| 451 | |
| 452 | * hysteresis reg is relative to therm, so the HW does not need to be
|
| 453 | * adjusted, we need to update our local copy only.
|
| 454 |
|
| 455 | priv->hyst = temp - (priv->therm - priv->hyst);
|
| 456 | priv->therm = temp;
|
| 457 |
|
| 458 | exit:
|
| 459 | mutex_unlock(&priv->access_lock);
|
| 460 | if (ret)
|
| 461 | return ret;
|
| 462 |
|
| 463 | return count;
|
| 464 | }
|
| 465 |
|
| 466 | static ssize_t hyst_show(struct device *dev, struct device_attribute *attr,
|
| 467 | char *buf)
|
| 468 | {
|
| 469 | struct stts751_priv *priv = dev_get_drvdata(dev);
|
| 470 |
|
| 471 | return sysfs_emit(buf, "%d\n", priv->hyst);
|
| 472 | }
|
| 473 |
|
| 474 | static ssize_t hyst_store(struct device *dev, struct device_attribute *attr,
|
| 475 | const char *buf, size_t count)
|
| 476 | {
|
| 477 | int ret;
|
| 478 | long temp;
|
| 479 |
|
| 480 | struct stts751_priv *priv = dev_get_drvdata(dev);
|
| 481 |
|
| 482 | if (kstrtol(buf, 10, &temp) < 0)
|
| 483 | return -EINVAL;
|
| 484 |
|
| 485 | mutex_lock(&priv->access_lock);
|
| 486 |
|
| 487 | temp = clamp_val(temp, -64000, priv->therm);
|
| 488 | priv->hyst = temp;
|
| 489 | dev_dbg(&priv->client->dev, "setting hyst %ld", temp);
|
| 490 | temp = priv->therm - temp;
|
| 491 | ret = stts751_set_temp_reg8(priv, temp, STTS751_REG_HYST);
|
| 492 | mutex_unlock(&priv->access_lock);
|
| 493 | if (ret)
|
| 494 | return ret;
|
| 495 |
|
| 496 | return count;
|
| 497 | }
|
| 498 |
|
| 499 | static ssize_t therm_trip_show(struct device *dev,
|
| 500 | struct device_attribute *attr, char *buf)
|
| 501 | {
|
| 502 | int ret;
|
| 503 | struct stts751_priv *priv = dev_get_drvdata(dev);
|
| 504 |
|
| 505 | mutex_lock(&priv->access_lock);
|
| 506 | ret = stts751_update(priv);
|
| 507 | mutex_unlock(&priv->access_lock);
|
| 508 | if (ret < 0)
|
| 509 | return ret;
|
| 510 |
|
| 511 | return sysfs_emit(buf, "%d\n", priv->therm_trip);
|
| 512 | }
|
| 513 |
|
| 514 | static ssize_t max_show(struct device *dev, struct device_attribute *attr,
|
| 515 | char *buf)
|
| 516 | {
|
| 517 | struct stts751_priv *priv = dev_get_drvdata(dev);
|
| 518 |
|
| 519 | return sysfs_emit(buf, "%d\n", priv->event_max);
|
| 520 | }
|
| 521 |
|
| 522 | static ssize_t max_store(struct device *dev, struct device_attribute *attr,
|
| 523 | const char *buf, size_t count)
|
| 524 | {
|
| 525 | int ret;
|
| 526 | long temp;
|
| 527 | struct stts751_priv *priv = dev_get_drvdata(dev);
|
| 528 |
|
| 529 | if (kstrtol(buf, 10, &temp) < 0)
|
| 530 | return -EINVAL;
|
| 531 |
|
| 532 | mutex_lock(&priv->access_lock);
|
| 533 |
|
| 534 | temp = clamp_val(temp, priv->event_min, 127937);
|
| 535 | ret = stts751_set_temp_reg16(priv, temp,
|
| 536 | STTS751_REG_HLIM_H, STTS751_REG_HLIM_L);
|
| 537 | if (ret)
|
| 538 | goto exit;
|
| 539 |
|
| 540 | dev_dbg(&priv->client->dev, "setting event max %ld", temp);
|
| 541 | priv->event_max = temp;
|
| 542 | ret = count;
|
| 543 | exit:
|
| 544 | mutex_unlock(&priv->access_lock);
|
| 545 | return ret;
|
| 546 | }
|
| 547 |
|
| 548 | static ssize_t min_show(struct device *dev, struct device_attribute *attr,
|
| 549 | char *buf)
|
| 550 | {
|
| 551 | struct stts751_priv *priv = dev_get_drvdata(dev);
|
| 552 |
|
| 553 | return sysfs_emit(buf, "%d\n", priv->event_min);
|
| 554 | }
|
| 555 |
|
| 556 | static ssize_t min_store(struct device *dev, struct device_attribute *attr,
|
| 557 | const char *buf, size_t count)
|
| 558 | {
|
| 559 | int ret;
|
| 560 | long temp;
|
| 561 | struct stts751_priv *priv = dev_get_drvdata(dev);
|
| 562 |
|
| 563 | if (kstrtol(buf, 10, &temp) < 0)
|
| 564 | return -EINVAL;
|
| 565 |
|
| 566 | mutex_lock(&priv->access_lock);
|
| 567 |
|
| 568 | temp = clamp_val(temp, -64000, priv->event_max);
|
| 569 | ret = stts751_set_temp_reg16(priv, temp,
|
| 570 | STTS751_REG_LLIM_H, STTS751_REG_LLIM_L);
|
| 571 | if (ret)
|
| 572 | goto exit;
|
| 573 |
|
| 574 | dev_dbg(&priv->client->dev, "setting event min %ld", temp);
|
| 575 | priv->event_min = temp;
|
| 576 | ret = count;
|
| 577 | exit:
|
| 578 | mutex_unlock(&priv->access_lock);
|
| 579 | return ret;
|
| 580 | }
|
| 581 |
|
| 582 | static ssize_t interval_show(struct device *dev,
|
| 583 | struct device_attribute *attr, char *buf)
|
| 584 | {
|
| 585 | struct stts751_priv *priv = dev_get_drvdata(dev);
|
| 586 |
|
| 587 | return sysfs_emit(buf, "%d\n",
|
| 588 | stts751_intervals[priv->interval]);
|
| 589 | }
|
| 590 |
|
| 591 | static ssize_t interval_store(struct device *dev,
|
| 592 | struct device_attribute *attr, const char *buf,
|
| 593 | size_t count)
|
| 594 | {
|
| 595 | unsigned long val;
|
| 596 | int idx;
|
| 597 | int ret = count;
|
| 598 | struct stts751_priv *priv = dev_get_drvdata(dev);
|
| 599 |
|
| 600 | if (kstrtoul(buf, 10, &val) < 0)
|
| 601 | return -EINVAL;
|
| 602 |
|
| 603 | idx = find_closest_descending(val, stts751_intervals,
|
| 604 | ARRAY_SIZE(stts751_intervals));
|
| 605 |
|
| 606 | dev_dbg(&priv->client->dev, "setting interval. req:%lu, idx: %d, val: %d",
|
| 607 | val, idx, stts751_intervals[idx]);
|
| 608 |
|
| 609 | mutex_lock(&priv->access_lock);
|
| 610 | if (priv->interval == idx)
|
| 611 | goto exit;
|
| 612 |
|
| 613 | |
| 614 | * In early development stages I've become suspicious about the chip
|
| 615 | * starting to misbehave if I ever set, even briefly, an invalid
|
| 616 | * configuration. While I'm not sure this is really needed, be
|
| 617 | * conservative and set rate/resolution in such an order that avoids
|
| 618 | * passing through an invalid configuration.
|
| 619 |
|
| 620 |
|
| 621 |
|
| 622 | if (priv->interval < idx) {
|
| 623 | dev_dbg(&priv->client->dev, "lower resolution, then modify convrate");
|
| 624 | priv->interval = idx;
|
| 625 | ret = stts751_adjust_resolution(priv);
|
| 626 | if (ret)
|
| 627 | goto exit;
|
| 628 | }
|
| 629 |
|
| 630 | ret = i2c_smbus_write_byte_data(priv->client, STTS751_REG_RATE, idx);
|
| 631 | if (ret)
|
| 632 | goto exit;
|
| 633 |
|
| 634 | if (priv->interval != idx) {
|
| 635 | dev_dbg(&priv->client->dev, "modify convrate, then raise resolution");
|
| 636 | priv->interval = idx;
|
| 637 | ret = stts751_adjust_resolution(priv);
|
| 638 | if (ret)
|
| 639 | goto exit;
|
| 640 | }
|
| 641 | ret = count;
|
| 642 | exit:
|
| 643 | mutex_unlock(&priv->access_lock);
|
| 644 |
|
| 645 | return ret;
|
| 646 | }
|
| 647 |
|
| 648 | static int stts751_detect(struct i2c_client *new_client,
|
| 649 | struct i2c_board_info *info)
|
| 650 | {
|
| 651 | struct i2c_adapter *adapter = new_client->adapter;
|
| 652 | const char *name;
|
| 653 | int tmp;
|
| 654 |
|
| 655 | if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
|
| 656 | return -ENODEV;
|
| 657 |
|
| 658 | tmp = i2c_smbus_read_byte_data(new_client, STTS751_REG_MAN_ID);
|
| 659 | if (tmp != ST_MAN_ID)
|
| 660 | return -ENODEV;
|
| 661 |
|
| 662 |
|
| 663 | tmp = i2c_smbus_read_byte_data(new_client, STTS751_REG_TEMP_L);
|
| 664 | if (tmp & 0xf)
|
| 665 | return -ENODEV;
|
| 666 |
|
| 667 | tmp = i2c_smbus_read_byte_data(new_client, STTS751_REG_HLIM_L);
|
| 668 | if (tmp & 0xf)
|
| 669 | return -ENODEV;
|
| 670 |
|
| 671 | tmp = i2c_smbus_read_byte_data(new_client, STTS751_REG_LLIM_L);
|
| 672 | if (tmp & 0xf)
|
| 673 | return -ENODEV;
|
| 674 |
|
| 675 |
|
| 676 | tmp = i2c_smbus_read_byte_data(new_client, STTS751_REG_SMBUS_TO);
|
| 677 | if (tmp & 0x7f)
|
| 678 | return -ENODEV;
|
| 679 |
|
| 680 | tmp = i2c_smbus_read_byte_data(new_client, STTS751_REG_PROD_ID);
|
| 681 |
|
| 682 | switch (tmp) {
|
| 683 | case STTS751_0_PROD_ID:
|
| 684 | name = "STTS751-0";
|
| 685 | break;
|
| 686 | case STTS751_1_PROD_ID:
|
| 687 | name = "STTS751-1";
|
| 688 | break;
|
| 689 | default:
|
| 690 | return -ENODEV;
|
| 691 | }
|
| 692 | dev_dbg(&new_client->dev, "Chip %s detected", name);
|
| 693 |
|
| 694 | strscpy(info->type, stts751_id[0].name, I2C_NAME_SIZE);
|
| 695 | return 0;
|
| 696 | }
|
| 697 |
|
| 698 | static int stts751_read_chip_config(struct stts751_priv *priv)
|
| 699 | {
|
| 700 | int ret;
|
| 701 | int tmp;
|
| 702 |
|
| 703 | ret = i2c_smbus_read_byte_data(priv->client, STTS751_REG_CONF);
|
| 704 | if (ret < 0)
|
| 705 | return ret;
|
| 706 | priv->config = ret;
|
| 707 | priv->res = (ret & STTS751_CONF_RES_MASK) >> STTS751_CONF_RES_SHIFT;
|
| 708 |
|
| 709 | ret = i2c_smbus_read_byte_data(priv->client, STTS751_REG_RATE);
|
| 710 | if (ret < 0)
|
| 711 | return ret;
|
| 712 | if (ret >= ARRAY_SIZE(stts751_intervals)) {
|
| 713 | dev_err(priv->dev, "Unrecognized conversion rate 0x%x\n", ret);
|
| 714 | return -ENODEV;
|
| 715 | }
|
| 716 | priv->interval = ret;
|
| 717 |
|
| 718 | ret = stts751_read_reg16(priv, &priv->event_max,
|
| 719 | STTS751_REG_HLIM_H, STTS751_REG_HLIM_L);
|
| 720 | if (ret)
|
| 721 | return ret;
|
| 722 |
|
| 723 | ret = stts751_read_reg16(priv, &priv->event_min,
|
| 724 | STTS751_REG_LLIM_H, STTS751_REG_LLIM_L);
|
| 725 | if (ret)
|
| 726 | return ret;
|
| 727 |
|
| 728 | ret = stts751_read_reg8(priv, &priv->therm, STTS751_REG_TLIM);
|
| 729 | if (ret)
|
| 730 | return ret;
|
| 731 |
|
| 732 | ret = stts751_read_reg8(priv, &tmp, STTS751_REG_HYST);
|
| 733 | if (ret)
|
| 734 | return ret;
|
| 735 | priv->hyst = priv->therm - tmp;
|
| 736 |
|
| 737 | return 0;
|
| 738 | }
|
| 739 |
|
| 740 | static SENSOR_DEVICE_ATTR_RO(temp1_input, input, 0);
|
| 741 | static SENSOR_DEVICE_ATTR_RW(temp1_min, min, 0);
|
| 742 | static SENSOR_DEVICE_ATTR_RW(temp1_max, max, 0);
|
| 743 | static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, min_alarm, 0);
|
| 744 | static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, max_alarm, 0);
|
| 745 | static SENSOR_DEVICE_ATTR_RW(temp1_crit, therm, 0);
|
| 746 | static SENSOR_DEVICE_ATTR_RW(temp1_crit_hyst, hyst, 0);
|
| 747 | static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, therm_trip, 0);
|
| 748 | static SENSOR_DEVICE_ATTR_RW(update_interval, interval, 0);
|
| 749 |
|
| 750 | static struct attribute *stts751_attrs[] = {
|
| 751 | &sensor_dev_attr_temp1_input.dev_attr.attr,
|
| 752 | &sensor_dev_attr_temp1_min.dev_attr.attr,
|
| 753 | &sensor_dev_attr_temp1_max.dev_attr.attr,
|
| 754 | &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
|
| 755 | &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
|
| 756 | &sensor_dev_attr_temp1_crit.dev_attr.attr,
|
| 757 | &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr,
|
| 758 | &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
|
| 759 | &sensor_dev_attr_update_interval.dev_attr.attr,
|
| 760 | NULL
|
| 761 | };
|
| 762 | ATTRIBUTE_GROUPS(stts751);
|
| 763 |
|
| 764 | static int stts751_probe(struct i2c_client *client)
|
| 765 | {
|
| 766 | struct stts751_priv *priv;
|
| 767 | int ret;
|
| 768 | bool smbus_nto;
|
| 769 | int rev_id;
|
| 770 |
|
| 771 | priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);
|
| 772 | if (!priv)
|
| 773 | return -ENOMEM;
|
| 774 |
|
| 775 | priv->client = client;
|
| 776 | priv->notify_max = true;
|
| 777 | priv->notify_min = true;
|
| 778 | i2c_set_clientdata(client, priv);
|
| 779 | mutex_init(&priv->access_lock);
|
| 780 |
|
| 781 | if (device_property_present(&client->dev,
|
| 782 | "smbus-timeout-disable")) {
|
| 783 | smbus_nto = device_property_read_bool(&client->dev,
|
| 784 | "smbus-timeout-disable");
|
| 785 |
|
| 786 | ret = i2c_smbus_write_byte_data(client, STTS751_REG_SMBUS_TO,
|
| 787 | smbus_nto ? 0 : 0x80);
|
| 788 | if (ret)
|
| 789 | return ret;
|
| 790 | }
|
| 791 |
|
| 792 | rev_id = i2c_smbus_read_byte_data(client, STTS751_REG_REV_ID);
|
| 793 | if (rev_id < 0)
|
| 794 | return -ENODEV;
|
| 795 | if (rev_id != 0x1) {
|
| 796 | dev_dbg(&client->dev, "Chip revision 0x%x is untested\n",
|
| 797 | rev_id);
|
| 798 | }
|
| 799 |
|
| 800 | ret = stts751_read_chip_config(priv);
|
| 801 | if (ret)
|
| 802 | return ret;
|
| 803 |
|
| 804 | priv->config &= ~(STTS751_CONF_STOP | STTS751_CONF_EVENT_DIS);
|
| 805 | ret = i2c_smbus_write_byte_data(client, STTS751_REG_CONF, priv->config);
|
| 806 | if (ret)
|
| 807 | return ret;
|
| 808 |
|
| 809 | priv->dev = devm_hwmon_device_register_with_groups(&client->dev,
|
| 810 | client->name, priv,
|
| 811 | stts751_groups);
|
| 812 | return PTR_ERR_OR_ZERO(priv->dev);
|
| 813 | }
|
| 814 |
|
| 815 | MODULE_DEVICE_TABLE(i2c, stts751_id);
|
| 816 |
|
| 817 | static struct i2c_driver stts751_driver = {
|
| 818 | .class = I2C_CLASS_HWMON,
|
| 819 | .driver = {
|
| 820 | .name = DEVNAME,
|
| 821 | .of_match_table = of_match_ptr(stts751_of_match),
|
| 822 | },
|
| 823 | .probe = stts751_probe,
|
| 824 | .id_table = stts751_id,
|
| 825 | .detect = stts751_detect,
|
| 826 | .alert = stts751_alert,
|
| 827 | .address_list = normal_i2c,
|
| 828 | };
|
| 829 |
|
| 830 | module_i2c_driver(stts751_driver);
|
| 831 |
|
| 832 | MODULE_AUTHOR("Andrea Merello <[email protected]>");
|
| 833 | MODULE_DESCRIPTION("STTS751 sensor driver");
|
| 834 | MODULE_LICENSE("GPL");
|