drivers/hwmon/adc128d818.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Driver for TI ADC128D818 System Monitor with Temperature Sensor
   4  *
   5  * Copyright (c) 2014 Guenter Roeck
   6  *
   7  * Derived from lm80.c
   8  * Copyright (C) 1998, 1999  Frodo Looijaard <frodol@dds.nl>
   9  *                           and Philip Edelbrock <phil@netroedge.com>
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/slab.h>
  14 #include <linux/jiffies.h>
  15 #include <linux/i2c.h>
  16 #include <linux/hwmon.h>
  17 #include <linux/hwmon-sysfs.h>
  18 #include <linux/err.h>
  19 #include <linux/regulator/consumer.h>
  20 #include <linux/mutex.h>
  21 #include <linux/bitops.h>
  22 #include <linux/of.h>
  23
  24 /* Addresses to scan
  25  * The chip also supports addresses 0x35..0x37. Don't scan those addresses
  26  * since they are also used by some EEPROMs, which may result in false
  27  * positives.
  28  */
  29 static const unsigned short normal_i2c[] = {
  30         0x1d, 0x1e, 0x1f, 0x2d, 0x2e, 0x2f, I2C_CLIENT_END };
  31
  32 /* registers */
  33 #define ADC128_REG_IN_MAX(nr)           (0x2a + (nr) * 2)
  34 #define ADC128_REG_IN_MIN(nr)           (0x2b + (nr) * 2)
  35 #define ADC128_REG_IN(nr)               (0x20 + (nr))
  36
  37 #define ADC128_REG_TEMP                 0x27
  38 #define ADC128_REG_TEMP_MAX             0x38
  39 #define ADC128_REG_TEMP_HYST            0x39
  40
  41 #define ADC128_REG_CONFIG               0x00
  42 #define ADC128_REG_ALARM                0x01
  43 #define ADC128_REG_MASK                 0x03
  44 #define ADC128_REG_CONV_RATE            0x07
  45 #define ADC128_REG_ONESHOT              0x09
  46 #define ADC128_REG_SHUTDOWN             0x0a
  47 #define ADC128_REG_CONFIG_ADV           0x0b
  48 #define ADC128_REG_BUSY_STATUS          0x0c
  49
  50 #define ADC128_REG_MAN_ID               0x3e
  51 #define ADC128_REG_DEV_ID               0x3f
  52
  53 /* No. of voltage entries in adc128_attrs */
  54 #define ADC128_ATTR_NUM_VOLT            (8 * 4)
  55
  56 /* Voltage inputs visible per operation mode */
  57 static const u8 num_inputs[] = { 7, 8, 4, 6 };
  58
  59 struct adc128_data {
  60         struct i2c_client *client;
  61         struct regulator *regulator;
  62         int vref;               /* Reference voltage in mV */
  63         struct mutex update_lock;
  64         u8 mode;                /* Operation mode */
  65         bool valid;             /* true if following fields are valid */
  66         unsigned long last_updated;     /* In jiffies */
  67
  68         u16 in[3][8];           /* Register value, normalized to 12 bit
  69                                  * 0: input voltage
  70                                  * 1: min limit
  71                                  * 2: max limit
  72                                  */
  73         s16 temp[3];            /* Register value, normalized to 9 bit
  74                                  * 0: sensor 1: limit 2: hyst
  75                                  */
  76         u8 alarms;              /* alarm register value */
  77 };
  78
  79 static struct adc128_data *adc128_update_device(struct device *dev)
  80 {
  81         struct adc128_data *data = dev_get_drvdata(dev);
  82         struct i2c_client *client = data->client;
  83         struct adc128_data *ret = data;
  84         int i, rv;
  85
  86         mutex_lock(&data->update_lock);
  87
  88         if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
  89                 for (i = 0; i < num_inputs[data->mode]; i++) {
  90                         rv = i2c_smbus_read_word_swapped(client,
  91                                                          ADC128_REG_IN(i));
  92                         if (rv < 0)
  93                                 goto abort;
  94                         data->in[0][i] = rv >> 4;
  95
  96                         rv = i2c_smbus_read_byte_data(client,
  97                                                       ADC128_REG_IN_MIN(i));
  98                         if (rv < 0)
  99                                 goto abort;
 100                         data->in[1][i] = rv << 4;
 101
 102                         rv = i2c_smbus_read_byte_data(client,
 103                                                       ADC128_REG_IN_MAX(i));
 104                         if (rv < 0)
 105                                 goto abort;
 106                         data->in[2][i] = rv << 4;
 107                 }
 108
 109                 if (data->mode != 1) {
 110                         rv = i2c_smbus_read_word_swapped(client,
 111                                                          ADC128_REG_TEMP);
 112                         if (rv < 0)
 113                                 goto abort;
 114                         data->temp[0] = rv >> 7;
 115
 116                         rv = i2c_smbus_read_byte_data(client,
 117                                                       ADC128_REG_TEMP_MAX);
 118                         if (rv < 0)
 119                                 goto abort;
 120                         data->temp[1] = rv << 1;
 121
 122                         rv = i2c_smbus_read_byte_data(client,
 123                                                       ADC128_REG_TEMP_HYST);
 124                         if (rv < 0)
 125                                 goto abort;
 126                         data->temp[2] = rv << 1;
 127                 }
 128
 129                 rv = i2c_smbus_read_byte_data(client, ADC128_REG_ALARM);
 130                 if (rv < 0)
 131                         goto abort;
 132                 data->alarms |= rv;
 133
 134                 data->last_updated = jiffies;
 135                 data->valid = true;
 136         }
 137         goto done;
 138
 139 abort:
 140         ret = ERR_PTR(rv);
 141         data->valid = false;
 142 done:
 143         mutex_unlock(&data->update_lock);
 144         return ret;
 145 }
 146
 147 static ssize_t adc128_in_show(struct device *dev,
 148                               struct device_attribute *attr, char *buf)
 149 {
 150         struct adc128_data *data = adc128_update_device(dev);
 151         int index = to_sensor_dev_attr_2(attr)->index;
 152         int nr = to_sensor_dev_attr_2(attr)->nr;
 153         int val;
 154
 155         if (IS_ERR(data))
 156                 return PTR_ERR(data);
 157
 158         val = DIV_ROUND_CLOSEST(data->in[index][nr] * data->vref, 4095);
 159         return sprintf(buf, "%d\n", val);
 160 }
 161
 162 static ssize_t adc128_in_store(struct device *dev,
 163                                struct device_attribute *attr, const char *buf,
 164                                size_t count)
 165 {
 166         struct adc128_data *data = dev_get_drvdata(dev);
 167         int index = to_sensor_dev_attr_2(attr)->index;
 168         int nr = to_sensor_dev_attr_2(attr)->nr;
 169         u8 reg, regval;
 170         long val;
 171         int err;
 172
 173         err = kstrtol(buf, 10, &val);
 174         if (err < 0)
 175                 return err;
 176
 177         mutex_lock(&data->update_lock);
 178         /* 10 mV LSB on limit registers */
 179         regval = clamp_val(DIV_ROUND_CLOSEST(val, 10), 0, 255);
 180         data->in[index][nr] = regval << 4;
 181         reg = index == 1 ? ADC128_REG_IN_MIN(nr) : ADC128_REG_IN_MAX(nr);
 182         i2c_smbus_write_byte_data(data->client, reg, regval);
 183         mutex_unlock(&data->update_lock);
 184
 185         return count;
 186 }
 187
 188 static ssize_t adc128_temp_show(struct device *dev,
 189                                 struct device_attribute *attr, char *buf)
 190 {
 191         struct adc128_data *data = adc128_update_device(dev);
 192         int index = to_sensor_dev_attr(attr)->index;
 193         int temp;
 194
 195         if (IS_ERR(data))
 196                 return PTR_ERR(data);
 197
 198         temp = sign_extend32(data->temp[index], 8);
 199         return sprintf(buf, "%d\n", temp * 500);/* 0.5 degrees C resolution */
 200 }
 201
 202 static ssize_t adc128_temp_store(struct device *dev,
 203                                  struct device_attribute *attr,
 204                                  const char *buf, size_t count)
 205 {
 206         struct adc128_data *data = dev_get_drvdata(dev);
 207         int index = to_sensor_dev_attr(attr)->index;
 208         long val;
 209         int err;
 210         s8 regval;
 211
 212         err = kstrtol(buf, 10, &val);
 213         if (err < 0)
 214                 return err;
 215
 216         mutex_lock(&data->update_lock);
 217         regval = clamp_val(DIV_ROUND_CLOSEST(val, 1000), -128, 127);
 218         data->temp[index] = regval << 1;
 219         i2c_smbus_write_byte_data(data->client,
 220                                   index == 1 ? ADC128_REG_TEMP_MAX
 221                                              : ADC128_REG_TEMP_HYST,
 222                                   regval);
 223         mutex_unlock(&data->update_lock);
 224
 225         return count;
 226 }
 227
 228 static ssize_t adc128_alarm_show(struct device *dev,
 229                                  struct device_attribute *attr, char *buf)
 230 {
 231         struct adc128_data *data = adc128_update_device(dev);
 232         int mask = 1 << to_sensor_dev_attr(attr)->index;
 233         u8 alarms;
 234
 235         if (IS_ERR(data))
 236                 return PTR_ERR(data);
 237
 238         /*
 239          * Clear an alarm after reporting it to user space. If it is still
 240          * active, the next update sequence will set the alarm bit again.
 241          */
 242         alarms = data->alarms;
 243         data->alarms &= ~mask;
 244
 245         return sprintf(buf, "%u\n", !!(alarms & mask));
 246 }
 247
 248 static umode_t adc128_is_visible(struct kobject *kobj,
 249                                  struct attribute *attr, int index)
 250 {
 251         struct device *dev = kobj_to_dev(kobj);
 252         struct adc128_data *data = dev_get_drvdata(dev);
 253
 254         if (index < ADC128_ATTR_NUM_VOLT) {
 255                 /* Voltage, visible according to num_inputs[] */
 256                 if (index >= num_inputs[data->mode] * 4)
 257                         return 0;
 258         } else {
 259                 /* Temperature, visible if not in mode 1 */
 260                 if (data->mode == 1)
 261                         return 0;
 262         }
 263
 264         return attr->mode;
 265 }
 266
 267 static SENSOR_DEVICE_ATTR_2_RO(in0_input, adc128_in, 0, 0);
 268 static SENSOR_DEVICE_ATTR_2_RW(in0_min, adc128_in, 0, 1);
 269 static SENSOR_DEVICE_ATTR_2_RW(in0_max, adc128_in, 0, 2);
 270
 271 static SENSOR_DEVICE_ATTR_2_RO(in1_input, adc128_in, 1, 0);
 272 static SENSOR_DEVICE_ATTR_2_RW(in1_min, adc128_in, 1, 1);
 273 static SENSOR_DEVICE_ATTR_2_RW(in1_max, adc128_in, 1, 2);
 274
 275 static SENSOR_DEVICE_ATTR_2_RO(in2_input, adc128_in, 2, 0);
 276 static SENSOR_DEVICE_ATTR_2_RW(in2_min, adc128_in, 2, 1);
 277 static SENSOR_DEVICE_ATTR_2_RW(in2_max, adc128_in, 2, 2);
 278
 279 static SENSOR_DEVICE_ATTR_2_RO(in3_input, adc128_in, 3, 0);
 280 static SENSOR_DEVICE_ATTR_2_RW(in3_min, adc128_in, 3, 1);
 281 static SENSOR_DEVICE_ATTR_2_RW(in3_max, adc128_in, 3, 2);
 282
 283 static SENSOR_DEVICE_ATTR_2_RO(in4_input, adc128_in, 4, 0);
 284 static SENSOR_DEVICE_ATTR_2_RW(in4_min, adc128_in, 4, 1);
 285 static SENSOR_DEVICE_ATTR_2_RW(in4_max, adc128_in, 4, 2);
 286
 287 static SENSOR_DEVICE_ATTR_2_RO(in5_input, adc128_in, 5, 0);
 288 static SENSOR_DEVICE_ATTR_2_RW(in5_min, adc128_in, 5, 1);
 289 static SENSOR_DEVICE_ATTR_2_RW(in5_max, adc128_in, 5, 2);
 290
 291 static SENSOR_DEVICE_ATTR_2_RO(in6_input, adc128_in, 6, 0);
 292 static SENSOR_DEVICE_ATTR_2_RW(in6_min, adc128_in, 6, 1);
 293 static SENSOR_DEVICE_ATTR_2_RW(in6_max, adc128_in, 6, 2);
 294
 295 static SENSOR_DEVICE_ATTR_2_RO(in7_input, adc128_in, 7, 0);
 296 static SENSOR_DEVICE_ATTR_2_RW(in7_min, adc128_in, 7, 1);
 297 static SENSOR_DEVICE_ATTR_2_RW(in7_max, adc128_in, 7, 2);
 298
 299 static SENSOR_DEVICE_ATTR_RO(temp1_input, adc128_temp, 0);
 300 static SENSOR_DEVICE_ATTR_RW(temp1_max, adc128_temp, 1);
 301 static SENSOR_DEVICE_ATTR_RW(temp1_max_hyst, adc128_temp, 2);
 302
 303 static SENSOR_DEVICE_ATTR_RO(in0_alarm, adc128_alarm, 0);
 304 static SENSOR_DEVICE_ATTR_RO(in1_alarm, adc128_alarm, 1);
 305 static SENSOR_DEVICE_ATTR_RO(in2_alarm, adc128_alarm, 2);
 306 static SENSOR_DEVICE_ATTR_RO(in3_alarm, adc128_alarm, 3);
 307 static SENSOR_DEVICE_ATTR_RO(in4_alarm, adc128_alarm, 4);
 308 static SENSOR_DEVICE_ATTR_RO(in5_alarm, adc128_alarm, 5);
 309 static SENSOR_DEVICE_ATTR_RO(in6_alarm, adc128_alarm, 6);
 310 static SENSOR_DEVICE_ATTR_RO(in7_alarm, adc128_alarm, 7);
 311 static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, adc128_alarm, 7);
 312
 313 static struct attribute *adc128_attrs[] = {
 314         &sensor_dev_attr_in0_alarm.dev_attr.attr,
 315         &sensor_dev_attr_in0_input.dev_attr.attr,
 316         &sensor_dev_attr_in0_max.dev_attr.attr,
 317         &sensor_dev_attr_in0_min.dev_attr.attr,
 318         &sensor_dev_attr_in1_alarm.dev_attr.attr,
 319         &sensor_dev_attr_in1_input.dev_attr.attr,
 320         &sensor_dev_attr_in1_max.dev_attr.attr,
 321         &sensor_dev_attr_in1_min.dev_attr.attr,
 322         &sensor_dev_attr_in2_alarm.dev_attr.attr,
 323         &sensor_dev_attr_in2_input.dev_attr.attr,
 324         &sensor_dev_attr_in2_max.dev_attr.attr,
 325         &sensor_dev_attr_in2_min.dev_attr.attr,
 326         &sensor_dev_attr_in3_alarm.dev_attr.attr,
 327         &sensor_dev_attr_in3_input.dev_attr.attr,
 328         &sensor_dev_attr_in3_max.dev_attr.attr,
 329         &sensor_dev_attr_in3_min.dev_attr.attr,
 330         &sensor_dev_attr_in4_alarm.dev_attr.attr,
 331         &sensor_dev_attr_in4_input.dev_attr.attr,
 332         &sensor_dev_attr_in4_max.dev_attr.attr,
 333         &sensor_dev_attr_in4_min.dev_attr.attr,
 334         &sensor_dev_attr_in5_alarm.dev_attr.attr,
 335         &sensor_dev_attr_in5_input.dev_attr.attr,
 336         &sensor_dev_attr_in5_max.dev_attr.attr,
 337         &sensor_dev_attr_in5_min.dev_attr.attr,
 338         &sensor_dev_attr_in6_alarm.dev_attr.attr,
 339         &sensor_dev_attr_in6_input.dev_attr.attr,
 340         &sensor_dev_attr_in6_max.dev_attr.attr,
 341         &sensor_dev_attr_in6_min.dev_attr.attr,
 342         &sensor_dev_attr_in7_alarm.dev_attr.attr,
 343         &sensor_dev_attr_in7_input.dev_attr.attr,
 344         &sensor_dev_attr_in7_max.dev_attr.attr,
 345         &sensor_dev_attr_in7_min.dev_attr.attr,
 346         &sensor_dev_attr_temp1_input.dev_attr.attr,
 347         &sensor_dev_attr_temp1_max.dev_attr.attr,
 348         &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 349         &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
 350         NULL
 351 };
 352
 353 static const struct attribute_group adc128_group = {
 354         .attrs = adc128_attrs,
 355         .is_visible = adc128_is_visible,
 356 };
 357 __ATTRIBUTE_GROUPS(adc128);
 358
 359 static int adc128_detect(struct i2c_client *client, struct i2c_board_info *info)
 360 {
 361         int man_id, dev_id;
 362
 363         if (!i2c_check_functionality(client->adapter,
 364                                      I2C_FUNC_SMBUS_BYTE_DATA |
 365                                      I2C_FUNC_SMBUS_WORD_DATA))
 366                 return -ENODEV;
 367
 368         man_id = i2c_smbus_read_byte_data(client, ADC128_REG_MAN_ID);
 369         dev_id = i2c_smbus_read_byte_data(client, ADC128_REG_DEV_ID);
 370         if (man_id != 0x01 || dev_id != 0x09)
 371                 return -ENODEV;
 372
 373         /* Check unused bits for confirmation */
 374         if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG) & 0xf4)
 375                 return -ENODEV;
 376         if (i2c_smbus_read_byte_data(client, ADC128_REG_CONV_RATE) & 0xfe)
 377                 return -ENODEV;
 378         if (i2c_smbus_read_byte_data(client, ADC128_REG_ONESHOT) & 0xfe)
 379                 return -ENODEV;
 380         if (i2c_smbus_read_byte_data(client, ADC128_REG_SHUTDOWN) & 0xfe)
 381                 return -ENODEV;
 382         if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV) & 0xf8)
 383                 return -ENODEV;
 384         if (i2c_smbus_read_byte_data(client, ADC128_REG_BUSY_STATUS) & 0xfc)
 385                 return -ENODEV;
 386
 387         strscpy(info->type, "adc128d818", I2C_NAME_SIZE);
 388
 389         return 0;
 390 }
 391
 392 static int adc128_init_client(struct adc128_data *data)
 393 {
 394         struct i2c_client *client = data->client;
 395         int err;
 396         u8 regval = 0x0;
 397
 398         /*
 399          * Reset chip to defaults.
 400          * This makes most other initializations unnecessary.
 401          */
 402         err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x80);
 403         if (err)
 404                 return err;
 405
 406         /* Set operation mode, if non-default */
 407         if (data->mode != 0)
 408                 regval |= data->mode << 1;
 409
 410         /* If external vref is selected, configure the chip to use it */
 411         if (data->regulator)
 412                 regval |= 0x01;
 413
 414         /* Write advanced configuration register */
 415         if (regval != 0x0) {
 416                 err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG_ADV,
 417                                                 regval);
 418                 if (err)
 419                         return err;
 420         }
 421
 422         /* Start monitoring */
 423         err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x01);
 424         if (err)
 425                 return err;
 426
 427         return 0;
 428 }
 429
 430 static int adc128_probe(struct i2c_client *client)
 431 {
 432         struct device *dev = &client->dev;
 433         struct regulator *regulator;
 434         struct device *hwmon_dev;
 435         struct adc128_data *data;
 436         int err, vref;
 437
 438         data = devm_kzalloc(dev, sizeof(struct adc128_data), GFP_KERNEL);
 439         if (!data)
 440                 return -ENOMEM;
 441
 442         /* vref is optional. If specified, is used as chip reference voltage */
 443         regulator = devm_regulator_get_optional(dev, "vref");
 444         if (!IS_ERR(regulator)) {
 445                 data->regulator = regulator;
 446                 err = regulator_enable(regulator);
 447                 if (err < 0)
 448                         return err;
 449                 vref = regulator_get_voltage(regulator);
 450                 if (vref < 0) {
 451                         err = vref;
 452                         goto error;
 453                 }
 454                 data->vref = DIV_ROUND_CLOSEST(vref, 1000);
 455         } else {
 456                 data->vref = 2560;      /* 2.56V, in mV */
 457         }
 458
 459         /* Operation mode is optional. If unspecified, keep current mode */
 460         if (of_property_read_u8(dev->of_node, "ti,mode", &data->mode) == 0) {
 461                 if (data->mode > 3) {
 462                         dev_err(dev, "invalid operation mode %d\n",
 463                                 data->mode);
 464                         err = -EINVAL;
 465                         goto error;
 466                 }
 467         } else {
 468                 err = i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV);
 469                 if (err < 0)
 470                         goto error;
 471                 data->mode = (err >> 1) & ADC128_REG_MASK;
 472         }
 473
 474         data->client = client;
 475         i2c_set_clientdata(client, data);
 476         mutex_init(&data->update_lock);
 477
 478         /* Initialize the chip */
 479         err = adc128_init_client(data);
 480         if (err < 0)
 481                 goto error;
 482
 483         hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
 484                                                            data, adc128_groups);
 485         if (IS_ERR(hwmon_dev)) {
 486                 err = PTR_ERR(hwmon_dev);
 487                 goto error;
 488         }
 489
 490         return 0;
 491
 492 error:
 493         if (data->regulator)
 494                 regulator_disable(data->regulator);
 495         return err;
 496 }
 497
 498 static void adc128_remove(struct i2c_client *client)
 499 {
 500         struct adc128_data *data = i2c_get_clientdata(client);
 501
 502         if (data->regulator)
 503                 regulator_disable(data->regulator);
 504 }
 505
 506 static const struct i2c_device_id adc128_id[] = {
 507         { "adc128d818", 0 },
 508         { }
 509 };
 510 MODULE_DEVICE_TABLE(i2c, adc128_id);
 511
 512 static const struct of_device_id __maybe_unused adc128_of_match[] = {
 513         { .compatible = "ti,adc128d818" },
 514         { },
 515 };
 516 MODULE_DEVICE_TABLE(of, adc128_of_match);
 517
 518 static struct i2c_driver adc128_driver = {
 519         .class          = I2C_CLASS_HWMON,
 520         .driver = {
 521                 .name   = "adc128d818",
 522                 .of_match_table = of_match_ptr(adc128_of_match),
 523         },
 524         .probe_new      = adc128_probe,
 525         .remove         = adc128_remove,
 526         .id_table       = adc128_id,
 527         .detect         = adc128_detect,
 528         .address_list   = normal_i2c,
 529 };
 530
 531 module_i2c_driver(adc128_driver);
 532
 533 MODULE_AUTHOR("Guenter Roeck");
 534 MODULE_DESCRIPTION("Driver for ADC128D818");
 535 MODULE_LICENSE("GPL");