drivers/hwmon/adc128d818.c

   1 /*
   2  * Driver for TI ADC128D818 System Monitor with Temperature Sensor
   3  *
   4  * Copyright (c) 2014 Guenter Roeck
   5  *
   6  * Derived from lm80.c
   7  * Copyright (C) 1998, 1999  Frodo Looijaard <frodol@dds.nl>
   8  *                           and Philip Edelbrock <phil@netroedge.com>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/slab.h>
  23 #include <linux/jiffies.h>
  24 #include <linux/i2c.h>
  25 #include <linux/hwmon.h>
  26 #include <linux/hwmon-sysfs.h>
  27 #include <linux/err.h>
  28 #include <linux/regulator/consumer.h>
  29 #include <linux/mutex.h>
  30 #include <linux/bitops.h>
  31 #include <linux/of.h>
  32
  33 /* Addresses to scan
  34  * The chip also supports addresses 0x35..0x37. Don't scan those addresses
  35  * since they are also used by some EEPROMs, which may result in false
  36  * positives.
  37  */
  38 static const unsigned short normal_i2c[] = {
  39         0x1d, 0x1e, 0x1f, 0x2d, 0x2e, 0x2f, I2C_CLIENT_END };
  40
  41 /* registers */
  42 #define ADC128_REG_IN_MAX(nr)           (0x2a + (nr) * 2)
  43 #define ADC128_REG_IN_MIN(nr)           (0x2b + (nr) * 2)
  44 #define ADC128_REG_IN(nr)               (0x20 + (nr))
  45
  46 #define ADC128_REG_TEMP                 0x27
  47 #define ADC128_REG_TEMP_MAX             0x38
  48 #define ADC128_REG_TEMP_HYST            0x39
  49
  50 #define ADC128_REG_CONFIG               0x00
  51 #define ADC128_REG_ALARM                0x01
  52 #define ADC128_REG_MASK                 0x03
  53 #define ADC128_REG_CONV_RATE            0x07
  54 #define ADC128_REG_ONESHOT              0x09
  55 #define ADC128_REG_SHUTDOWN             0x0a
  56 #define ADC128_REG_CONFIG_ADV           0x0b
  57 #define ADC128_REG_BUSY_STATUS          0x0c
  58
  59 #define ADC128_REG_MAN_ID               0x3e
  60 #define ADC128_REG_DEV_ID               0x3f
  61
  62 struct adc128_data {
  63         struct i2c_client *client;
  64         struct regulator *regulator;
  65         int vref;               /* Reference voltage in mV */
  66         struct mutex update_lock;
  67         u8 mode;                /* Operation mode */
  68         bool valid;             /* true if following fields are valid */
  69         unsigned long last_updated;     /* In jiffies */
  70
  71         u16 in[3][7];           /* Register value, normalized to 12 bit
  72                                  * 0: input voltage
  73                                  * 1: min limit
  74                                  * 2: max limit
  75                                  */
  76         s16 temp[3];            /* Register value, normalized to 9 bit
  77                                  * 0: sensor 1: limit 2: hyst
  78                                  */
  79         u8 alarms;              /* alarm register value */
  80 };
  81
  82 static struct adc128_data *adc128_update_device(struct device *dev)
  83 {
  84         struct adc128_data *data = dev_get_drvdata(dev);
  85         struct i2c_client *client = data->client;
  86         struct adc128_data *ret = data;
  87         int i, rv;
  88
  89         mutex_lock(&data->update_lock);
  90
  91         if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
  92                 for (i = 0; i < 7; i++) {
  93                         rv = i2c_smbus_read_word_swapped(client,
  94                                                          ADC128_REG_IN(i));
  95                         if (rv < 0)
  96                                 goto abort;
  97                         data->in[0][i] = rv >> 4;
  98
  99                         rv = i2c_smbus_read_byte_data(client,
 100                                                       ADC128_REG_IN_MIN(i));
 101                         if (rv < 0)
 102                                 goto abort;
 103                         data->in[1][i] = rv << 4;
 104
 105                         rv = i2c_smbus_read_byte_data(client,
 106                                                       ADC128_REG_IN_MAX(i));
 107                         if (rv < 0)
 108                                 goto abort;
 109                         data->in[2][i] = rv << 4;
 110                 }
 111
 112                 rv = i2c_smbus_read_word_swapped(client, ADC128_REG_TEMP);
 113                 if (rv < 0)
 114                         goto abort;
 115                 data->temp[0] = rv >> 7;
 116
 117                 rv = i2c_smbus_read_byte_data(client, 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, ADC128_REG_TEMP_HYST);
 123                 if (rv < 0)
 124                         goto abort;
 125                 data->temp[2] = rv << 1;
 126
 127                 rv = i2c_smbus_read_byte_data(client, ADC128_REG_ALARM);
 128                 if (rv < 0)
 129                         goto abort;
 130                 data->alarms |= rv;
 131
 132                 data->last_updated = jiffies;
 133                 data->valid = true;
 134         }
 135         goto done;
 136
 137 abort:
 138         ret = ERR_PTR(rv);
 139         data->valid = false;
 140 done:
 141         mutex_unlock(&data->update_lock);
 142         return ret;
 143 }
 144
 145 static ssize_t adc128_show_in(struct device *dev, struct device_attribute *attr,
 146                               char *buf)
 147 {
 148         struct adc128_data *data = adc128_update_device(dev);
 149         int index = to_sensor_dev_attr_2(attr)->index;
 150         int nr = to_sensor_dev_attr_2(attr)->nr;
 151         int val;
 152
 153         if (IS_ERR(data))
 154                 return PTR_ERR(data);
 155
 156         val = DIV_ROUND_CLOSEST(data->in[index][nr] * data->vref, 4095);
 157         return sprintf(buf, "%d\n", val);
 158 }
 159
 160 static ssize_t adc128_set_in(struct device *dev, struct device_attribute *attr,
 161                              const char *buf, size_t count)
 162 {
 163         struct adc128_data *data = dev_get_drvdata(dev);
 164         int index = to_sensor_dev_attr_2(attr)->index;
 165         int nr = to_sensor_dev_attr_2(attr)->nr;
 166         u8 reg, regval;
 167         long val;
 168         int err;
 169
 170         err = kstrtol(buf, 10, &val);
 171         if (err < 0)
 172                 return err;
 173
 174         mutex_lock(&data->update_lock);
 175         /* 10 mV LSB on limit registers */
 176         regval = clamp_val(DIV_ROUND_CLOSEST(val, 10), 0, 255);
 177         data->in[index][nr] = regval << 4;
 178         reg = index == 1 ? ADC128_REG_IN_MIN(nr) : ADC128_REG_IN_MAX(nr);
 179         i2c_smbus_write_byte_data(data->client, reg, regval);
 180         mutex_unlock(&data->update_lock);
 181
 182         return count;
 183 }
 184
 185 static ssize_t adc128_show_temp(struct device *dev,
 186                                 struct device_attribute *attr, char *buf)
 187 {
 188         struct adc128_data *data = adc128_update_device(dev);
 189         int index = to_sensor_dev_attr(attr)->index;
 190         int temp;
 191
 192         if (IS_ERR(data))
 193                 return PTR_ERR(data);
 194
 195         temp = sign_extend32(data->temp[index], 8);
 196         return sprintf(buf, "%d\n", temp * 500);/* 0.5 degrees C resolution */
 197 }
 198
 199 static ssize_t adc128_set_temp(struct device *dev,
 200                                struct device_attribute *attr,
 201                                const char *buf, size_t count)
 202 {
 203         struct adc128_data *data = dev_get_drvdata(dev);
 204         int index = to_sensor_dev_attr(attr)->index;
 205         long val;
 206         int err;
 207         s8 regval;
 208
 209         err = kstrtol(buf, 10, &val);
 210         if (err < 0)
 211                 return err;
 212
 213         mutex_lock(&data->update_lock);
 214         regval = clamp_val(DIV_ROUND_CLOSEST(val, 1000), -128, 127);
 215         data->temp[index] = regval << 1;
 216         i2c_smbus_write_byte_data(data->client,
 217                                   index == 1 ? ADC128_REG_TEMP_MAX
 218                                              : ADC128_REG_TEMP_HYST,
 219                                   regval);
 220         mutex_unlock(&data->update_lock);
 221
 222         return count;
 223 }
 224
 225 static ssize_t adc128_show_alarm(struct device *dev,
 226                                  struct device_attribute *attr, char *buf)
 227 {
 228         struct adc128_data *data = adc128_update_device(dev);
 229         int mask = 1 << to_sensor_dev_attr(attr)->index;
 230         u8 alarms;
 231
 232         if (IS_ERR(data))
 233                 return PTR_ERR(data);
 234
 235         /*
 236          * Clear an alarm after reporting it to user space. If it is still
 237          * active, the next update sequence will set the alarm bit again.
 238          */
 239         alarms = data->alarms;
 240         data->alarms &= ~mask;
 241
 242         return sprintf(buf, "%u\n", !!(alarms & mask));
 243 }
 244
 245 static SENSOR_DEVICE_ATTR_2(in0_input, S_IRUGO,
 246                             adc128_show_in, NULL, 0, 0);
 247 static SENSOR_DEVICE_ATTR_2(in0_min, S_IWUSR | S_IRUGO,
 248                             adc128_show_in, adc128_set_in, 0, 1);
 249 static SENSOR_DEVICE_ATTR_2(in0_max, S_IWUSR | S_IRUGO,
 250                             adc128_show_in, adc128_set_in, 0, 2);
 251
 252 static SENSOR_DEVICE_ATTR_2(in1_input, S_IRUGO,
 253                             adc128_show_in, NULL, 1, 0);
 254 static SENSOR_DEVICE_ATTR_2(in1_min, S_IWUSR | S_IRUGO,
 255                             adc128_show_in, adc128_set_in, 1, 1);
 256 static SENSOR_DEVICE_ATTR_2(in1_max, S_IWUSR | S_IRUGO,
 257                             adc128_show_in, adc128_set_in, 1, 2);
 258
 259 static SENSOR_DEVICE_ATTR_2(in2_input, S_IRUGO,
 260                             adc128_show_in, NULL, 2, 0);
 261 static SENSOR_DEVICE_ATTR_2(in2_min, S_IWUSR | S_IRUGO,
 262                             adc128_show_in, adc128_set_in, 2, 1);
 263 static SENSOR_DEVICE_ATTR_2(in2_max, S_IWUSR | S_IRUGO,
 264                             adc128_show_in, adc128_set_in, 2, 2);
 265
 266 static SENSOR_DEVICE_ATTR_2(in3_input, S_IRUGO,
 267                             adc128_show_in, NULL, 3, 0);
 268 static SENSOR_DEVICE_ATTR_2(in3_min, S_IWUSR | S_IRUGO,
 269                             adc128_show_in, adc128_set_in, 3, 1);
 270 static SENSOR_DEVICE_ATTR_2(in3_max, S_IWUSR | S_IRUGO,
 271                             adc128_show_in, adc128_set_in, 3, 2);
 272
 273 static SENSOR_DEVICE_ATTR_2(in4_input, S_IRUGO,
 274                             adc128_show_in, NULL, 4, 0);
 275 static SENSOR_DEVICE_ATTR_2(in4_min, S_IWUSR | S_IRUGO,
 276                             adc128_show_in, adc128_set_in, 4, 1);
 277 static SENSOR_DEVICE_ATTR_2(in4_max, S_IWUSR | S_IRUGO,
 278                             adc128_show_in, adc128_set_in, 4, 2);
 279
 280 static SENSOR_DEVICE_ATTR_2(in5_input, S_IRUGO,
 281                             adc128_show_in, NULL, 5, 0);
 282 static SENSOR_DEVICE_ATTR_2(in5_min, S_IWUSR | S_IRUGO,
 283                             adc128_show_in, adc128_set_in, 5, 1);
 284 static SENSOR_DEVICE_ATTR_2(in5_max, S_IWUSR | S_IRUGO,
 285                             adc128_show_in, adc128_set_in, 5, 2);
 286
 287 static SENSOR_DEVICE_ATTR_2(in6_input, S_IRUGO,
 288                             adc128_show_in, NULL, 6, 0);
 289 static SENSOR_DEVICE_ATTR_2(in6_min, S_IWUSR | S_IRUGO,
 290                             adc128_show_in, adc128_set_in, 6, 1);
 291 static SENSOR_DEVICE_ATTR_2(in6_max, S_IWUSR | S_IRUGO,
 292                             adc128_show_in, adc128_set_in, 6, 2);
 293
 294 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, adc128_show_temp, NULL, 0);
 295 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
 296                           adc128_show_temp, adc128_set_temp, 1);
 297 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
 298                           adc128_show_temp, adc128_set_temp, 2);
 299
 300 static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, adc128_show_alarm, NULL, 0);
 301 static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, adc128_show_alarm, NULL, 1);
 302 static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, adc128_show_alarm, NULL, 2);
 303 static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, adc128_show_alarm, NULL, 3);
 304 static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, adc128_show_alarm, NULL, 4);
 305 static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, adc128_show_alarm, NULL, 5);
 306 static SENSOR_DEVICE_ATTR(in6_alarm, S_IRUGO, adc128_show_alarm, NULL, 6);
 307 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, adc128_show_alarm, NULL, 7);
 308
 309 static struct attribute *adc128_attrs[] = {
 310         &sensor_dev_attr_in0_min.dev_attr.attr,
 311         &sensor_dev_attr_in1_min.dev_attr.attr,
 312         &sensor_dev_attr_in2_min.dev_attr.attr,
 313         &sensor_dev_attr_in3_min.dev_attr.attr,
 314         &sensor_dev_attr_in4_min.dev_attr.attr,
 315         &sensor_dev_attr_in5_min.dev_attr.attr,
 316         &sensor_dev_attr_in6_min.dev_attr.attr,
 317         &sensor_dev_attr_in0_max.dev_attr.attr,
 318         &sensor_dev_attr_in1_max.dev_attr.attr,
 319         &sensor_dev_attr_in2_max.dev_attr.attr,
 320         &sensor_dev_attr_in3_max.dev_attr.attr,
 321         &sensor_dev_attr_in4_max.dev_attr.attr,
 322         &sensor_dev_attr_in5_max.dev_attr.attr,
 323         &sensor_dev_attr_in6_max.dev_attr.attr,
 324         &sensor_dev_attr_in0_input.dev_attr.attr,
 325         &sensor_dev_attr_in1_input.dev_attr.attr,
 326         &sensor_dev_attr_in2_input.dev_attr.attr,
 327         &sensor_dev_attr_in3_input.dev_attr.attr,
 328         &sensor_dev_attr_in4_input.dev_attr.attr,
 329         &sensor_dev_attr_in5_input.dev_attr.attr,
 330         &sensor_dev_attr_in6_input.dev_attr.attr,
 331         &sensor_dev_attr_temp1_input.dev_attr.attr,
 332         &sensor_dev_attr_temp1_max.dev_attr.attr,
 333         &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
 334         &sensor_dev_attr_in0_alarm.dev_attr.attr,
 335         &sensor_dev_attr_in1_alarm.dev_attr.attr,
 336         &sensor_dev_attr_in2_alarm.dev_attr.attr,
 337         &sensor_dev_attr_in3_alarm.dev_attr.attr,
 338         &sensor_dev_attr_in4_alarm.dev_attr.attr,
 339         &sensor_dev_attr_in5_alarm.dev_attr.attr,
 340         &sensor_dev_attr_in6_alarm.dev_attr.attr,
 341         &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 342         NULL
 343 };
 344 ATTRIBUTE_GROUPS(adc128);
 345
 346 static int adc128_detect(struct i2c_client *client, struct i2c_board_info *info)
 347 {
 348         int man_id, dev_id;
 349
 350         if (!i2c_check_functionality(client->adapter,
 351                                      I2C_FUNC_SMBUS_BYTE_DATA |
 352                                      I2C_FUNC_SMBUS_WORD_DATA))
 353                 return -ENODEV;
 354
 355         man_id = i2c_smbus_read_byte_data(client, ADC128_REG_MAN_ID);
 356         dev_id = i2c_smbus_read_byte_data(client, ADC128_REG_DEV_ID);
 357         if (man_id != 0x01 || dev_id != 0x09)
 358                 return -ENODEV;
 359
 360         /* Check unused bits for confirmation */
 361         if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG) & 0xf4)
 362                 return -ENODEV;
 363         if (i2c_smbus_read_byte_data(client, ADC128_REG_CONV_RATE) & 0xfe)
 364                 return -ENODEV;
 365         if (i2c_smbus_read_byte_data(client, ADC128_REG_ONESHOT) & 0xfe)
 366                 return -ENODEV;
 367         if (i2c_smbus_read_byte_data(client, ADC128_REG_SHUTDOWN) & 0xfe)
 368                 return -ENODEV;
 369         if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV) & 0xf8)
 370                 return -ENODEV;
 371         if (i2c_smbus_read_byte_data(client, ADC128_REG_BUSY_STATUS) & 0xfc)
 372                 return -ENODEV;
 373
 374         strlcpy(info->type, "adc128d818", I2C_NAME_SIZE);
 375
 376         return 0;
 377 }
 378
 379 static int adc128_init_client(struct adc128_data *data)
 380 {
 381         struct i2c_client *client = data->client;
 382         int err;
 383
 384         /*
 385          * Reset chip to defaults.
 386          * This makes most other initializations unnecessary.
 387          */
 388         err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x80);
 389         if (err)
 390                 return err;
 391
 392         /* Set operation mode, if non-default */
 393         if (data->mode != 0) {
 394                 err = i2c_smbus_write_byte_data(client,
 395                                                 ADC128_REG_CONFIG_ADV,
 396                                                 data->mode << 1);
 397                 if (err)
 398                         return err;
 399         }
 400
 401         /* Start monitoring */
 402         err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x01);
 403         if (err)
 404                 return err;
 405
 406         /* If external vref is selected, configure the chip to use it */
 407         if (data->regulator) {
 408                 err = i2c_smbus_write_byte_data(client,
 409                                                 ADC128_REG_CONFIG_ADV, 0x01);
 410                 if (err)
 411                         return err;
 412         }
 413
 414         return 0;
 415 }
 416
 417 static int adc128_probe(struct i2c_client *client,
 418                         const struct i2c_device_id *id)
 419 {
 420         struct device *dev = &client->dev;
 421         struct regulator *regulator;
 422         struct device *hwmon_dev;
 423         struct adc128_data *data;
 424         int err, vref;
 425
 426         data = devm_kzalloc(dev, sizeof(struct adc128_data), GFP_KERNEL);
 427         if (!data)
 428                 return -ENOMEM;
 429
 430         /* vref is optional. If specified, is used as chip reference voltage */
 431         regulator = devm_regulator_get_optional(dev, "vref");
 432         if (!IS_ERR(regulator)) {
 433                 data->regulator = regulator;
 434                 err = regulator_enable(regulator);
 435                 if (err < 0)
 436                         return err;
 437                 vref = regulator_get_voltage(regulator);
 438                 if (vref < 0) {
 439                         err = vref;
 440                         goto error;
 441                 }
 442                 data->vref = DIV_ROUND_CLOSEST(vref, 1000);
 443         } else {
 444                 data->vref = 2560;      /* 2.56V, in mV */
 445         }
 446
 447         /* Operation mode is optional and defaults to mode 0 */
 448         if (of_property_read_u8(dev->of_node, "ti,mode", &data->mode) == 0) {
 449                 /* Currently only mode 0 supported */
 450                 if (data->mode != 0) {
 451                         dev_err(dev, "unsupported operation mode %d\n",
 452                                 data->mode);
 453                         err = -EINVAL;
 454                         goto error;
 455                 }
 456         } else {
 457                 data->mode = 0;
 458         }
 459
 460         data->client = client;
 461         i2c_set_clientdata(client, data);
 462         mutex_init(&data->update_lock);
 463
 464         /* Initialize the chip */
 465         err = adc128_init_client(data);
 466         if (err < 0)
 467                 goto error;
 468
 469         hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
 470                                                            data, adc128_groups);
 471         if (IS_ERR(hwmon_dev)) {
 472                 err = PTR_ERR(hwmon_dev);
 473                 goto error;
 474         }
 475
 476         return 0;
 477
 478 error:
 479         if (data->regulator)
 480                 regulator_disable(data->regulator);
 481         return err;
 482 }
 483
 484 static int adc128_remove(struct i2c_client *client)
 485 {
 486         struct adc128_data *data = i2c_get_clientdata(client);
 487
 488         if (data->regulator)
 489                 regulator_disable(data->regulator);
 490
 491         return 0;
 492 }
 493
 494 static const struct i2c_device_id adc128_id[] = {
 495         { "adc128d818", 0 },
 496         { }
 497 };
 498 MODULE_DEVICE_TABLE(i2c, adc128_id);
 499
 500 static struct i2c_driver adc128_driver = {
 501         .class          = I2C_CLASS_HWMON,
 502         .driver = {
 503                 .name   = "adc128d818",
 504         },
 505         .probe          = adc128_probe,
 506         .remove         = adc128_remove,
 507         .id_table       = adc128_id,
 508         .detect         = adc128_detect,
 509         .address_list   = normal_i2c,
 510 };
 511
 512 module_i2c_driver(adc128_driver);
 513
 514 MODULE_AUTHOR("Guenter Roeck");
 515 MODULE_DESCRIPTION("Driver for ADC128D818");
 516 MODULE_LICENSE("GPL");