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
  31 /* Addresses to scan
  32  * The chip also supports addresses 0x35..0x37. Don't scan those addresses
  33  * since they are also used by some EEPROMs, which may result in false
  34  * positives.
  35  */
  36 static const unsigned short normal_i2c[] = {
  37         0x1d, 0x1e, 0x1f, 0x2d, 0x2e, 0x2f, I2C_CLIENT_END };
  38
  39 /* registers */
  40 #define ADC128_REG_IN_MAX(nr)           (0x2a + (nr) * 2)
  41 #define ADC128_REG_IN_MIN(nr)           (0x2b + (nr) * 2)
  42 #define ADC128_REG_IN(nr)               (0x20 + (nr))
  43
  44 #define ADC128_REG_TEMP                 0x27
  45 #define ADC128_REG_TEMP_MAX             0x38
  46 #define ADC128_REG_TEMP_HYST            0x39
  47
  48 #define ADC128_REG_CONFIG               0x00
  49 #define ADC128_REG_ALARM                0x01
  50 #define ADC128_REG_MASK                 0x03
  51 #define ADC128_REG_CONV_RATE            0x07
  52 #define ADC128_REG_ONESHOT              0x09
  53 #define ADC128_REG_SHUTDOWN             0x0a
  54 #define ADC128_REG_CONFIG_ADV           0x0b
  55 #define ADC128_REG_BUSY_STATUS          0x0c
  56
  57 #define ADC128_REG_MAN_ID               0x3e
  58 #define ADC128_REG_DEV_ID               0x3f
  59
  60 struct adc128_data {
  61         struct i2c_client *client;
  62         struct regulator *regulator;
  63         int vref;               /* Reference voltage in mV */
  64         struct mutex update_lock;
  65         bool valid;             /* true if following fields are valid */
  66         unsigned long last_updated;     /* In jiffies */
  67
  68         u16 in[3][7];           /* 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 < 7; 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                 rv = i2c_smbus_read_word_swapped(client, ADC128_REG_TEMP);
 110                 if (rv < 0)
 111                         goto abort;
 112                 data->temp[0] = rv >> 7;
 113
 114                 rv = i2c_smbus_read_byte_data(client, ADC128_REG_TEMP_MAX);
 115                 if (rv < 0)
 116                         goto abort;
 117                 data->temp[1] = rv << 1;
 118
 119                 rv = i2c_smbus_read_byte_data(client, ADC128_REG_TEMP_HYST);
 120                 if (rv < 0)
 121                         goto abort;
 122                 data->temp[2] = rv << 1;
 123
 124                 rv = i2c_smbus_read_byte_data(client, ADC128_REG_ALARM);
 125                 if (rv < 0)
 126                         goto abort;
 127                 data->alarms |= rv;
 128
 129                 data->last_updated = jiffies;
 130                 data->valid = true;
 131         }
 132         goto done;
 133
 134 abort:
 135         ret = ERR_PTR(rv);
 136         data->valid = false;
 137 done:
 138         mutex_unlock(&data->update_lock);
 139         return ret;
 140 }
 141
 142 static ssize_t adc128_show_in(struct device *dev, struct device_attribute *attr,
 143                               char *buf)
 144 {
 145         struct adc128_data *data = adc128_update_device(dev);
 146         int index = to_sensor_dev_attr_2(attr)->index;
 147         int nr = to_sensor_dev_attr_2(attr)->nr;
 148         int val;
 149
 150         if (IS_ERR(data))
 151                 return PTR_ERR(data);
 152
 153         val = DIV_ROUND_CLOSEST(data->in[index][nr] * data->vref, 4095);
 154         return sprintf(buf, "%d\n", val);
 155 }
 156
 157 static ssize_t adc128_set_in(struct device *dev, struct device_attribute *attr,
 158                              const char *buf, size_t count)
 159 {
 160         struct adc128_data *data = dev_get_drvdata(dev);
 161         int index = to_sensor_dev_attr_2(attr)->index;
 162         int nr = to_sensor_dev_attr_2(attr)->nr;
 163         u8 reg, regval;
 164         long val;
 165         int err;
 166
 167         err = kstrtol(buf, 10, &val);
 168         if (err < 0)
 169                 return err;
 170
 171         mutex_lock(&data->update_lock);
 172         /* 10 mV LSB on limit registers */
 173         regval = clamp_val(DIV_ROUND_CLOSEST(val, 10), 0, 255);
 174         data->in[index][nr] = regval << 4;
 175         reg = index == 1 ? ADC128_REG_IN_MIN(nr) : ADC128_REG_IN_MAX(nr);
 176         i2c_smbus_write_byte_data(data->client, reg, regval);
 177         mutex_unlock(&data->update_lock);
 178
 179         return count;
 180 }
 181
 182 static ssize_t adc128_show_temp(struct device *dev,
 183                                 struct device_attribute *attr, char *buf)
 184 {
 185         struct adc128_data *data = adc128_update_device(dev);
 186         int index = to_sensor_dev_attr(attr)->index;
 187         int temp;
 188
 189         if (IS_ERR(data))
 190                 return PTR_ERR(data);
 191
 192         temp = (data->temp[index] << 7) >> 7;   /* sign extend */
 193         return sprintf(buf, "%d\n", temp * 500);/* 0.5 degrees C resolution */
 194 }
 195
 196 static ssize_t adc128_set_temp(struct device *dev,
 197                                struct device_attribute *attr,
 198                                const char *buf, size_t count)
 199 {
 200         struct adc128_data *data = dev_get_drvdata(dev);
 201         int index = to_sensor_dev_attr(attr)->index;
 202         long val;
 203         int err;
 204         s8 regval;
 205
 206         err = kstrtol(buf, 10, &val);
 207         if (err < 0)
 208                 return err;
 209
 210         mutex_lock(&data->update_lock);
 211         regval = clamp_val(DIV_ROUND_CLOSEST(val, 1000), -128, 127);
 212         data->temp[index] = regval << 1;
 213         i2c_smbus_write_byte_data(data->client,
 214                                   index == 1 ? ADC128_REG_TEMP_MAX
 215                                              : ADC128_REG_TEMP_HYST,
 216                                   regval);
 217         mutex_unlock(&data->update_lock);
 218
 219         return count;
 220 }
 221
 222 static ssize_t adc128_show_alarm(struct device *dev,
 223                                  struct device_attribute *attr, char *buf)
 224 {
 225         struct adc128_data *data = adc128_update_device(dev);
 226         int mask = 1 << to_sensor_dev_attr(attr)->index;
 227         u8 alarms;
 228
 229         if (IS_ERR(data))
 230                 return PTR_ERR(data);
 231
 232         /*
 233          * Clear an alarm after reporting it to user space. If it is still
 234          * active, the next update sequence will set the alarm bit again.
 235          */
 236         alarms = data->alarms;
 237         data->alarms &= ~mask;
 238
 239         return sprintf(buf, "%u\n", !!(alarms & mask));
 240 }
 241
 242 static SENSOR_DEVICE_ATTR_2(in0_input, S_IRUGO,
 243                             adc128_show_in, NULL, 0, 0);
 244 static SENSOR_DEVICE_ATTR_2(in0_min, S_IWUSR | S_IRUGO,
 245                             adc128_show_in, adc128_set_in, 0, 1);
 246 static SENSOR_DEVICE_ATTR_2(in0_max, S_IWUSR | S_IRUGO,
 247                             adc128_show_in, adc128_set_in, 0, 2);
 248
 249 static SENSOR_DEVICE_ATTR_2(in1_input, S_IRUGO,
 250                             adc128_show_in, NULL, 1, 0);
 251 static SENSOR_DEVICE_ATTR_2(in1_min, S_IWUSR | S_IRUGO,
 252                             adc128_show_in, adc128_set_in, 1, 1);
 253 static SENSOR_DEVICE_ATTR_2(in1_max, S_IWUSR | S_IRUGO,
 254                             adc128_show_in, adc128_set_in, 1, 2);
 255
 256 static SENSOR_DEVICE_ATTR_2(in2_input, S_IRUGO,
 257                             adc128_show_in, NULL, 2, 0);
 258 static SENSOR_DEVICE_ATTR_2(in2_min, S_IWUSR | S_IRUGO,
 259                             adc128_show_in, adc128_set_in, 2, 1);
 260 static SENSOR_DEVICE_ATTR_2(in2_max, S_IWUSR | S_IRUGO,
 261                             adc128_show_in, adc128_set_in, 2, 2);
 262
 263 static SENSOR_DEVICE_ATTR_2(in3_input, S_IRUGO,
 264                             adc128_show_in, NULL, 3, 0);
 265 static SENSOR_DEVICE_ATTR_2(in3_min, S_IWUSR | S_IRUGO,
 266                             adc128_show_in, adc128_set_in, 3, 1);
 267 static SENSOR_DEVICE_ATTR_2(in3_max, S_IWUSR | S_IRUGO,
 268                             adc128_show_in, adc128_set_in, 3, 2);
 269
 270 static SENSOR_DEVICE_ATTR_2(in4_input, S_IRUGO,
 271                             adc128_show_in, NULL, 4, 0);
 272 static SENSOR_DEVICE_ATTR_2(in4_min, S_IWUSR | S_IRUGO,
 273                             adc128_show_in, adc128_set_in, 4, 1);
 274 static SENSOR_DEVICE_ATTR_2(in4_max, S_IWUSR | S_IRUGO,
 275                             adc128_show_in, adc128_set_in, 4, 2);
 276
 277 static SENSOR_DEVICE_ATTR_2(in5_input, S_IRUGO,
 278                             adc128_show_in, NULL, 5, 0);
 279 static SENSOR_DEVICE_ATTR_2(in5_min, S_IWUSR | S_IRUGO,
 280                             adc128_show_in, adc128_set_in, 5, 1);
 281 static SENSOR_DEVICE_ATTR_2(in5_max, S_IWUSR | S_IRUGO,
 282                             adc128_show_in, adc128_set_in, 5, 2);
 283
 284 static SENSOR_DEVICE_ATTR_2(in6_input, S_IRUGO,
 285                             adc128_show_in, NULL, 6, 0);
 286 static SENSOR_DEVICE_ATTR_2(in6_min, S_IWUSR | S_IRUGO,
 287                             adc128_show_in, adc128_set_in, 6, 1);
 288 static SENSOR_DEVICE_ATTR_2(in6_max, S_IWUSR | S_IRUGO,
 289                             adc128_show_in, adc128_set_in, 6, 2);
 290
 291 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, adc128_show_temp, NULL, 0);
 292 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
 293                           adc128_show_temp, adc128_set_temp, 1);
 294 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
 295                           adc128_show_temp, adc128_set_temp, 2);
 296
 297 static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, adc128_show_alarm, NULL, 0);
 298 static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, adc128_show_alarm, NULL, 1);
 299 static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, adc128_show_alarm, NULL, 2);
 300 static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, adc128_show_alarm, NULL, 3);
 301 static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, adc128_show_alarm, NULL, 4);
 302 static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, adc128_show_alarm, NULL, 5);
 303 static SENSOR_DEVICE_ATTR(in6_alarm, S_IRUGO, adc128_show_alarm, NULL, 6);
 304 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, adc128_show_alarm, NULL, 7);
 305
 306 static struct attribute *adc128_attrs[] = {
 307         &sensor_dev_attr_in0_min.dev_attr.attr,
 308         &sensor_dev_attr_in1_min.dev_attr.attr,
 309         &sensor_dev_attr_in2_min.dev_attr.attr,
 310         &sensor_dev_attr_in3_min.dev_attr.attr,
 311         &sensor_dev_attr_in4_min.dev_attr.attr,
 312         &sensor_dev_attr_in5_min.dev_attr.attr,
 313         &sensor_dev_attr_in6_min.dev_attr.attr,
 314         &sensor_dev_attr_in0_max.dev_attr.attr,
 315         &sensor_dev_attr_in1_max.dev_attr.attr,
 316         &sensor_dev_attr_in2_max.dev_attr.attr,
 317         &sensor_dev_attr_in3_max.dev_attr.attr,
 318         &sensor_dev_attr_in4_max.dev_attr.attr,
 319         &sensor_dev_attr_in5_max.dev_attr.attr,
 320         &sensor_dev_attr_in6_max.dev_attr.attr,
 321         &sensor_dev_attr_in0_input.dev_attr.attr,
 322         &sensor_dev_attr_in1_input.dev_attr.attr,
 323         &sensor_dev_attr_in2_input.dev_attr.attr,
 324         &sensor_dev_attr_in3_input.dev_attr.attr,
 325         &sensor_dev_attr_in4_input.dev_attr.attr,
 326         &sensor_dev_attr_in5_input.dev_attr.attr,
 327         &sensor_dev_attr_in6_input.dev_attr.attr,
 328         &sensor_dev_attr_temp1_input.dev_attr.attr,
 329         &sensor_dev_attr_temp1_max.dev_attr.attr,
 330         &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
 331         &sensor_dev_attr_in0_alarm.dev_attr.attr,
 332         &sensor_dev_attr_in1_alarm.dev_attr.attr,
 333         &sensor_dev_attr_in2_alarm.dev_attr.attr,
 334         &sensor_dev_attr_in3_alarm.dev_attr.attr,
 335         &sensor_dev_attr_in4_alarm.dev_attr.attr,
 336         &sensor_dev_attr_in5_alarm.dev_attr.attr,
 337         &sensor_dev_attr_in6_alarm.dev_attr.attr,
 338         &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 339         NULL
 340 };
 341 ATTRIBUTE_GROUPS(adc128);
 342
 343 static int adc128_detect(struct i2c_client *client, struct i2c_board_info *info)
 344 {
 345         int man_id, dev_id;
 346
 347         if (!i2c_check_functionality(client->adapter,
 348                                      I2C_FUNC_SMBUS_BYTE_DATA |
 349                                      I2C_FUNC_SMBUS_WORD_DATA))
 350                 return -ENODEV;
 351
 352         man_id = i2c_smbus_read_byte_data(client, ADC128_REG_MAN_ID);
 353         dev_id = i2c_smbus_read_byte_data(client, ADC128_REG_DEV_ID);
 354         if (man_id != 0x01 || dev_id != 0x09)
 355                 return -ENODEV;
 356
 357         /* Check unused bits for confirmation */
 358         if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG) & 0xf4)
 359                 return -ENODEV;
 360         if (i2c_smbus_read_byte_data(client, ADC128_REG_CONV_RATE) & 0xfe)
 361                 return -ENODEV;
 362         if (i2c_smbus_read_byte_data(client, ADC128_REG_ONESHOT) & 0xfe)
 363                 return -ENODEV;
 364         if (i2c_smbus_read_byte_data(client, ADC128_REG_SHUTDOWN) & 0xfe)
 365                 return -ENODEV;
 366         if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV) & 0xf8)
 367                 return -ENODEV;
 368         if (i2c_smbus_read_byte_data(client, ADC128_REG_BUSY_STATUS) & 0xfc)
 369                 return -ENODEV;
 370
 371         strlcpy(info->type, "adc128d818", I2C_NAME_SIZE);
 372
 373         return 0;
 374 }
 375
 376 static int adc128_init_client(struct adc128_data *data)
 377 {
 378         struct i2c_client *client = data->client;
 379         int err;
 380
 381         /*
 382          * Reset chip to defaults.
 383          * This makes most other initializations unnecessary.
 384          */
 385         err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x80);
 386         if (err)
 387                 return err;
 388
 389         /* Start monitoring */
 390         err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x01);
 391         if (err)
 392                 return err;
 393
 394         /* If external vref is selected, configure the chip to use it */
 395         if (data->regulator) {
 396                 err = i2c_smbus_write_byte_data(client,
 397                                                 ADC128_REG_CONFIG_ADV, 0x01);
 398                 if (err)
 399                         return err;
 400         }
 401
 402         return 0;
 403 }
 404
 405 static int adc128_probe(struct i2c_client *client,
 406                         const struct i2c_device_id *id)
 407 {
 408         struct device *dev = &client->dev;
 409         struct regulator *regulator;
 410         struct device *hwmon_dev;
 411         struct adc128_data *data;
 412         int err, vref;
 413
 414         data = devm_kzalloc(dev, sizeof(struct adc128_data), GFP_KERNEL);
 415         if (!data)
 416                 return -ENOMEM;
 417
 418         /* vref is optional. If specified, is used as chip reference voltage */
 419         regulator = devm_regulator_get_optional(dev, "vref");
 420         if (!IS_ERR(regulator)) {
 421                 data->regulator = regulator;
 422                 err = regulator_enable(regulator);
 423                 if (err < 0)
 424                         return err;
 425                 vref = regulator_get_voltage(regulator);
 426                 if (vref < 0) {
 427                         err = vref;
 428                         goto error;
 429                 }
 430                 data->vref = DIV_ROUND_CLOSEST(vref, 1000);
 431         } else {
 432                 data->vref = 2560;      /* 2.56V, in mV */
 433         }
 434
 435         data->client = client;
 436         i2c_set_clientdata(client, data);
 437         mutex_init(&data->update_lock);
 438
 439         /* Initialize the chip */
 440         err = adc128_init_client(data);
 441         if (err < 0)
 442                 goto error;
 443
 444         hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
 445                                                            data, adc128_groups);
 446         if (IS_ERR(hwmon_dev)) {
 447                 err = PTR_ERR(hwmon_dev);
 448                 goto error;
 449         }
 450
 451         return 0;
 452
 453 error:
 454         if (data->regulator)
 455                 regulator_disable(data->regulator);
 456         return err;
 457 }
 458
 459 static int adc128_remove(struct i2c_client *client)
 460 {
 461         struct adc128_data *data = i2c_get_clientdata(client);
 462
 463         if (data->regulator)
 464                 regulator_disable(data->regulator);
 465
 466         return 0;
 467 }
 468
 469 static const struct i2c_device_id adc128_id[] = {
 470         { "adc128d818", 0 },
 471         { }
 472 };
 473 MODULE_DEVICE_TABLE(i2c, adc128_id);
 474
 475 static struct i2c_driver adc128_driver = {
 476         .class          = I2C_CLASS_HWMON,
 477         .driver = {
 478                 .name   = "adc128d818",
 479         },
 480         .probe          = adc128_probe,
 481         .remove         = adc128_remove,
 482         .id_table       = adc128_id,
 483         .detect         = adc128_detect,
 484         .address_list   = normal_i2c,
 485 };
 486
 487 module_i2c_driver(adc128_driver);
 488
 489 MODULE_AUTHOR("Guenter Roeck");
 490 MODULE_DESCRIPTION("Driver for ADC128D818");
 491 MODULE_LICENSE("GPL");