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
  32 /* Addresses to scan
  33  * The chip also supports addresses 0x35..0x37. Don't scan those addresses
  34  * since they are also used by some EEPROMs, which may result in false
  35  * positives.
  36  */
  37 static const unsigned short normal_i2c[] = {
  38         0x1d, 0x1e, 0x1f, 0x2d, 0x2e, 0x2f, I2C_CLIENT_END };
  39
  40 /* registers */
  41 #define ADC128_REG_IN_MAX(nr)           (0x2a + (nr) * 2)
  42 #define ADC128_REG_IN_MIN(nr)           (0x2b + (nr) * 2)
  43 #define ADC128_REG_IN(nr)               (0x20 + (nr))
  44
  45 #define ADC128_REG_TEMP                 0x27
  46 #define ADC128_REG_TEMP_MAX             0x38
  47 #define ADC128_REG_TEMP_HYST            0x39
  48
  49 #define ADC128_REG_CONFIG               0x00
  50 #define ADC128_REG_ALARM                0x01
  51 #define ADC128_REG_MASK                 0x03
  52 #define ADC128_REG_CONV_RATE            0x07
  53 #define ADC128_REG_ONESHOT              0x09
  54 #define ADC128_REG_SHUTDOWN             0x0a
  55 #define ADC128_REG_CONFIG_ADV           0x0b
  56 #define ADC128_REG_BUSY_STATUS          0x0c
  57
  58 #define ADC128_REG_MAN_ID               0x3e
  59 #define ADC128_REG_DEV_ID               0x3f
  60
  61 struct adc128_data {
  62         struct i2c_client *client;
  63         struct regulator *regulator;
  64         int vref;               /* Reference voltage in mV */
  65         struct mutex update_lock;
  66         bool valid;             /* true if following fields are valid */
  67         unsigned long last_updated;     /* In jiffies */
  68
  69         u16 in[3][7];           /* Register value, normalized to 12 bit
  70                                  * 0: input voltage
  71                                  * 1: min limit
  72                                  * 2: max limit
  73                                  */
  74         s16 temp[3];            /* Register value, normalized to 9 bit
  75                                  * 0: sensor 1: limit 2: hyst
  76                                  */
  77         u8 alarms;              /* alarm register value */
  78 };
  79
  80 static struct adc128_data *adc128_update_device(struct device *dev)
  81 {
  82         struct adc128_data *data = dev_get_drvdata(dev);
  83         struct i2c_client *client = data->client;
  84         struct adc128_data *ret = data;
  85         int i, rv;
  86
  87         mutex_lock(&data->update_lock);
  88
  89         if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
  90                 for (i = 0; i < 7; i++) {
  91                         rv = i2c_smbus_read_word_swapped(client,
  92                                                          ADC128_REG_IN(i));
  93                         if (rv < 0)
  94                                 goto abort;
  95                         data->in[0][i] = rv >> 4;
  96
  97                         rv = i2c_smbus_read_byte_data(client,
  98                                                       ADC128_REG_IN_MIN(i));
  99                         if (rv < 0)
 100                                 goto abort;
 101                         data->in[1][i] = rv << 4;
 102
 103                         rv = i2c_smbus_read_byte_data(client,
 104                                                       ADC128_REG_IN_MAX(i));
 105                         if (rv < 0)
 106                                 goto abort;
 107                         data->in[2][i] = rv << 4;
 108                 }
 109
 110                 rv = i2c_smbus_read_word_swapped(client, ADC128_REG_TEMP);
 111                 if (rv < 0)
 112                         goto abort;
 113                 data->temp[0] = rv >> 7;
 114
 115                 rv = i2c_smbus_read_byte_data(client, ADC128_REG_TEMP_MAX);
 116                 if (rv < 0)
 117                         goto abort;
 118                 data->temp[1] = rv << 1;
 119
 120                 rv = i2c_smbus_read_byte_data(client, ADC128_REG_TEMP_HYST);
 121                 if (rv < 0)
 122                         goto abort;
 123                 data->temp[2] = rv << 1;
 124
 125                 rv = i2c_smbus_read_byte_data(client, ADC128_REG_ALARM);
 126                 if (rv < 0)
 127                         goto abort;
 128                 data->alarms |= rv;
 129
 130                 data->last_updated = jiffies;
 131                 data->valid = true;
 132         }
 133         goto done;
 134
 135 abort:
 136         ret = ERR_PTR(rv);
 137         data->valid = false;
 138 done:
 139         mutex_unlock(&data->update_lock);
 140         return ret;
 141 }
 142
 143 static ssize_t adc128_show_in(struct device *dev, struct device_attribute *attr,
 144                               char *buf)
 145 {
 146         struct adc128_data *data = adc128_update_device(dev);
 147         int index = to_sensor_dev_attr_2(attr)->index;
 148         int nr = to_sensor_dev_attr_2(attr)->nr;
 149         int val;
 150
 151         if (IS_ERR(data))
 152                 return PTR_ERR(data);
 153
 154         val = DIV_ROUND_CLOSEST(data->in[index][nr] * data->vref, 4095);
 155         return sprintf(buf, "%d\n", val);
 156 }
 157
 158 static ssize_t adc128_set_in(struct device *dev, struct device_attribute *attr,
 159                              const char *buf, size_t count)
 160 {
 161         struct adc128_data *data = dev_get_drvdata(dev);
 162         int index = to_sensor_dev_attr_2(attr)->index;
 163         int nr = to_sensor_dev_attr_2(attr)->nr;
 164         u8 reg, regval;
 165         long val;
 166         int err;
 167
 168         err = kstrtol(buf, 10, &val);
 169         if (err < 0)
 170                 return err;
 171
 172         mutex_lock(&data->update_lock);
 173         /* 10 mV LSB on limit registers */
 174         regval = clamp_val(DIV_ROUND_CLOSEST(val, 10), 0, 255);
 175         data->in[index][nr] = regval << 4;
 176         reg = index == 1 ? ADC128_REG_IN_MIN(nr) : ADC128_REG_IN_MAX(nr);
 177         i2c_smbus_write_byte_data(data->client, reg, regval);
 178         mutex_unlock(&data->update_lock);
 179
 180         return count;
 181 }
 182
 183 static ssize_t adc128_show_temp(struct device *dev,
 184                                 struct device_attribute *attr, char *buf)
 185 {
 186         struct adc128_data *data = adc128_update_device(dev);
 187         int index = to_sensor_dev_attr(attr)->index;
 188         int temp;
 189
 190         if (IS_ERR(data))
 191                 return PTR_ERR(data);
 192
 193         temp = sign_extend32(data->temp[index], 8);
 194         return sprintf(buf, "%d\n", temp * 500);/* 0.5 degrees C resolution */
 195 }
 196
 197 static ssize_t adc128_set_temp(struct device *dev,
 198                                struct device_attribute *attr,
 199                                const char *buf, size_t count)
 200 {
 201         struct adc128_data *data = dev_get_drvdata(dev);
 202         int index = to_sensor_dev_attr(attr)->index;
 203         long val;
 204         int err;
 205         s8 regval;
 206
 207         err = kstrtol(buf, 10, &val);
 208         if (err < 0)
 209                 return err;
 210
 211         mutex_lock(&data->update_lock);
 212         regval = clamp_val(DIV_ROUND_CLOSEST(val, 1000), -128, 127);
 213         data->temp[index] = regval << 1;
 214         i2c_smbus_write_byte_data(data->client,
 215                                   index == 1 ? ADC128_REG_TEMP_MAX
 216                                              : ADC128_REG_TEMP_HYST,
 217                                   regval);
 218         mutex_unlock(&data->update_lock);
 219
 220         return count;
 221 }
 222
 223 static ssize_t adc128_show_alarm(struct device *dev,
 224                                  struct device_attribute *attr, char *buf)
 225 {
 226         struct adc128_data *data = adc128_update_device(dev);
 227         int mask = 1 << to_sensor_dev_attr(attr)->index;
 228         u8 alarms;
 229
 230         if (IS_ERR(data))
 231                 return PTR_ERR(data);
 232
 233         /*
 234          * Clear an alarm after reporting it to user space. If it is still
 235          * active, the next update sequence will set the alarm bit again.
 236          */
 237         alarms = data->alarms;
 238         data->alarms &= ~mask;
 239
 240         return sprintf(buf, "%u\n", !!(alarms & mask));
 241 }
 242
 243 static SENSOR_DEVICE_ATTR_2(in0_input, S_IRUGO,
 244                             adc128_show_in, NULL, 0, 0);
 245 static SENSOR_DEVICE_ATTR_2(in0_min, S_IWUSR | S_IRUGO,
 246                             adc128_show_in, adc128_set_in, 0, 1);
 247 static SENSOR_DEVICE_ATTR_2(in0_max, S_IWUSR | S_IRUGO,
 248                             adc128_show_in, adc128_set_in, 0, 2);
 249
 250 static SENSOR_DEVICE_ATTR_2(in1_input, S_IRUGO,
 251                             adc128_show_in, NULL, 1, 0);
 252 static SENSOR_DEVICE_ATTR_2(in1_min, S_IWUSR | S_IRUGO,
 253                             adc128_show_in, adc128_set_in, 1, 1);
 254 static SENSOR_DEVICE_ATTR_2(in1_max, S_IWUSR | S_IRUGO,
 255                             adc128_show_in, adc128_set_in, 1, 2);
 256
 257 static SENSOR_DEVICE_ATTR_2(in2_input, S_IRUGO,
 258                             adc128_show_in, NULL, 2, 0);
 259 static SENSOR_DEVICE_ATTR_2(in2_min, S_IWUSR | S_IRUGO,
 260                             adc128_show_in, adc128_set_in, 2, 1);
 261 static SENSOR_DEVICE_ATTR_2(in2_max, S_IWUSR | S_IRUGO,
 262                             adc128_show_in, adc128_set_in, 2, 2);
 263
 264 static SENSOR_DEVICE_ATTR_2(in3_input, S_IRUGO,
 265                             adc128_show_in, NULL, 3, 0);
 266 static SENSOR_DEVICE_ATTR_2(in3_min, S_IWUSR | S_IRUGO,
 267                             adc128_show_in, adc128_set_in, 3, 1);
 268 static SENSOR_DEVICE_ATTR_2(in3_max, S_IWUSR | S_IRUGO,
 269                             adc128_show_in, adc128_set_in, 3, 2);
 270
 271 static SENSOR_DEVICE_ATTR_2(in4_input, S_IRUGO,
 272                             adc128_show_in, NULL, 4, 0);
 273 static SENSOR_DEVICE_ATTR_2(in4_min, S_IWUSR | S_IRUGO,
 274                             adc128_show_in, adc128_set_in, 4, 1);
 275 static SENSOR_DEVICE_ATTR_2(in4_max, S_IWUSR | S_IRUGO,
 276                             adc128_show_in, adc128_set_in, 4, 2);
 277
 278 static SENSOR_DEVICE_ATTR_2(in5_input, S_IRUGO,
 279                             adc128_show_in, NULL, 5, 0);
 280 static SENSOR_DEVICE_ATTR_2(in5_min, S_IWUSR | S_IRUGO,
 281                             adc128_show_in, adc128_set_in, 5, 1);
 282 static SENSOR_DEVICE_ATTR_2(in5_max, S_IWUSR | S_IRUGO,
 283                             adc128_show_in, adc128_set_in, 5, 2);
 284
 285 static SENSOR_DEVICE_ATTR_2(in6_input, S_IRUGO,
 286                             adc128_show_in, NULL, 6, 0);
 287 static SENSOR_DEVICE_ATTR_2(in6_min, S_IWUSR | S_IRUGO,
 288                             adc128_show_in, adc128_set_in, 6, 1);
 289 static SENSOR_DEVICE_ATTR_2(in6_max, S_IWUSR | S_IRUGO,
 290                             adc128_show_in, adc128_set_in, 6, 2);
 291
 292 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, adc128_show_temp, NULL, 0);
 293 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
 294                           adc128_show_temp, adc128_set_temp, 1);
 295 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
 296                           adc128_show_temp, adc128_set_temp, 2);
 297
 298 static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, adc128_show_alarm, NULL, 0);
 299 static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, adc128_show_alarm, NULL, 1);
 300 static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, adc128_show_alarm, NULL, 2);
 301 static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, adc128_show_alarm, NULL, 3);
 302 static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, adc128_show_alarm, NULL, 4);
 303 static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, adc128_show_alarm, NULL, 5);
 304 static SENSOR_DEVICE_ATTR(in6_alarm, S_IRUGO, adc128_show_alarm, NULL, 6);
 305 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, adc128_show_alarm, NULL, 7);
 306
 307 static struct attribute *adc128_attrs[] = {
 308         &sensor_dev_attr_in0_min.dev_attr.attr,
 309         &sensor_dev_attr_in1_min.dev_attr.attr,
 310         &sensor_dev_attr_in2_min.dev_attr.attr,
 311         &sensor_dev_attr_in3_min.dev_attr.attr,
 312         &sensor_dev_attr_in4_min.dev_attr.attr,
 313         &sensor_dev_attr_in5_min.dev_attr.attr,
 314         &sensor_dev_attr_in6_min.dev_attr.attr,
 315         &sensor_dev_attr_in0_max.dev_attr.attr,
 316         &sensor_dev_attr_in1_max.dev_attr.attr,
 317         &sensor_dev_attr_in2_max.dev_attr.attr,
 318         &sensor_dev_attr_in3_max.dev_attr.attr,
 319         &sensor_dev_attr_in4_max.dev_attr.attr,
 320         &sensor_dev_attr_in5_max.dev_attr.attr,
 321         &sensor_dev_attr_in6_max.dev_attr.attr,
 322         &sensor_dev_attr_in0_input.dev_attr.attr,
 323         &sensor_dev_attr_in1_input.dev_attr.attr,
 324         &sensor_dev_attr_in2_input.dev_attr.attr,
 325         &sensor_dev_attr_in3_input.dev_attr.attr,
 326         &sensor_dev_attr_in4_input.dev_attr.attr,
 327         &sensor_dev_attr_in5_input.dev_attr.attr,
 328         &sensor_dev_attr_in6_input.dev_attr.attr,
 329         &sensor_dev_attr_temp1_input.dev_attr.attr,
 330         &sensor_dev_attr_temp1_max.dev_attr.attr,
 331         &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
 332         &sensor_dev_attr_in0_alarm.dev_attr.attr,
 333         &sensor_dev_attr_in1_alarm.dev_attr.attr,
 334         &sensor_dev_attr_in2_alarm.dev_attr.attr,
 335         &sensor_dev_attr_in3_alarm.dev_attr.attr,
 336         &sensor_dev_attr_in4_alarm.dev_attr.attr,
 337         &sensor_dev_attr_in5_alarm.dev_attr.attr,
 338         &sensor_dev_attr_in6_alarm.dev_attr.attr,
 339         &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 340         NULL
 341 };
 342 ATTRIBUTE_GROUPS(adc128);
 343
 344 static int adc128_detect(struct i2c_client *client, struct i2c_board_info *info)
 345 {
 346         int man_id, dev_id;
 347
 348         if (!i2c_check_functionality(client->adapter,
 349                                      I2C_FUNC_SMBUS_BYTE_DATA |
 350                                      I2C_FUNC_SMBUS_WORD_DATA))
 351                 return -ENODEV;
 352
 353         man_id = i2c_smbus_read_byte_data(client, ADC128_REG_MAN_ID);
 354         dev_id = i2c_smbus_read_byte_data(client, ADC128_REG_DEV_ID);
 355         if (man_id != 0x01 || dev_id != 0x09)
 356                 return -ENODEV;
 357
 358         /* Check unused bits for confirmation */
 359         if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG) & 0xf4)
 360                 return -ENODEV;
 361         if (i2c_smbus_read_byte_data(client, ADC128_REG_CONV_RATE) & 0xfe)
 362                 return -ENODEV;
 363         if (i2c_smbus_read_byte_data(client, ADC128_REG_ONESHOT) & 0xfe)
 364                 return -ENODEV;
 365         if (i2c_smbus_read_byte_data(client, ADC128_REG_SHUTDOWN) & 0xfe)
 366                 return -ENODEV;
 367         if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV) & 0xf8)
 368                 return -ENODEV;
 369         if (i2c_smbus_read_byte_data(client, ADC128_REG_BUSY_STATUS) & 0xfc)
 370                 return -ENODEV;
 371
 372         strlcpy(info->type, "adc128d818", I2C_NAME_SIZE);
 373
 374         return 0;
 375 }
 376
 377 static int adc128_init_client(struct adc128_data *data)
 378 {
 379         struct i2c_client *client = data->client;
 380         int err;
 381
 382         /*
 383          * Reset chip to defaults.
 384          * This makes most other initializations unnecessary.
 385          */
 386         err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x80);
 387         if (err)
 388                 return err;
 389
 390         /* Start monitoring */
 391         err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x01);
 392         if (err)
 393                 return err;
 394
 395         /* If external vref is selected, configure the chip to use it */
 396         if (data->regulator) {
 397                 err = i2c_smbus_write_byte_data(client,
 398                                                 ADC128_REG_CONFIG_ADV, 0x01);
 399                 if (err)
 400                         return err;
 401         }
 402
 403         return 0;
 404 }
 405
 406 static int adc128_probe(struct i2c_client *client,
 407                         const struct i2c_device_id *id)
 408 {
 409         struct device *dev = &client->dev;
 410         struct regulator *regulator;
 411         struct device *hwmon_dev;
 412         struct adc128_data *data;
 413         int err, vref;
 414
 415         data = devm_kzalloc(dev, sizeof(struct adc128_data), GFP_KERNEL);
 416         if (!data)
 417                 return -ENOMEM;
 418
 419         /* vref is optional. If specified, is used as chip reference voltage */
 420         regulator = devm_regulator_get_optional(dev, "vref");
 421         if (!IS_ERR(regulator)) {
 422                 data->regulator = regulator;
 423                 err = regulator_enable(regulator);
 424                 if (err < 0)
 425                         return err;
 426                 vref = regulator_get_voltage(regulator);
 427                 if (vref < 0) {
 428                         err = vref;
 429                         goto error;
 430                 }
 431                 data->vref = DIV_ROUND_CLOSEST(vref, 1000);
 432         } else {
 433                 data->vref = 2560;      /* 2.56V, in mV */
 434         }
 435
 436         data->client = client;
 437         i2c_set_clientdata(client, data);
 438         mutex_init(&data->update_lock);
 439
 440         /* Initialize the chip */
 441         err = adc128_init_client(data);
 442         if (err < 0)
 443                 goto error;
 444
 445         hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
 446                                                            data, adc128_groups);
 447         if (IS_ERR(hwmon_dev)) {
 448                 err = PTR_ERR(hwmon_dev);
 449                 goto error;
 450         }
 451
 452         return 0;
 453
 454 error:
 455         if (data->regulator)
 456                 regulator_disable(data->regulator);
 457         return err;
 458 }
 459
 460 static int adc128_remove(struct i2c_client *client)
 461 {
 462         struct adc128_data *data = i2c_get_clientdata(client);
 463
 464         if (data->regulator)
 465                 regulator_disable(data->regulator);
 466
 467         return 0;
 468 }
 469
 470 static const struct i2c_device_id adc128_id[] = {
 471         { "adc128d818", 0 },
 472         { }
 473 };
 474 MODULE_DEVICE_TABLE(i2c, adc128_id);
 475
 476 static struct i2c_driver adc128_driver = {
 477         .class          = I2C_CLASS_HWMON,
 478         .driver = {
 479                 .name   = "adc128d818",
 480         },
 481         .probe          = adc128_probe,
 482         .remove         = adc128_remove,
 483         .id_table       = adc128_id,
 484         .detect         = adc128_detect,
 485         .address_list   = normal_i2c,
 486 };
 487
 488 module_i2c_driver(adc128_driver);
 489
 490 MODULE_AUTHOR("Guenter Roeck");
 491 MODULE_DESCRIPTION("Driver for ADC128D818");
 492 MODULE_LICENSE("GPL");