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 <[email protected]>
   9  *                           and Philip Edelbrock <[email protected]>
  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         int vref;               /* Reference voltage in mV */
  62         struct mutex update_lock;
  63         u8 mode;                /* Operation mode */
  64         bool valid;             /* true if following fields are valid */
  65         unsigned long last_updated;     /* In jiffies */
  66
  67         u16 in[3][8];           /* Register value, normalized to 12 bit
  68                                  * 0: input voltage
  69                                  * 1: min limit
  70                                  * 2: max limit
  71                                  */
  72         s16 temp[3];            /* Register value, normalized to 9 bit
  73                                  * 0: sensor 1: limit 2: hyst
  74                                  */
  75         u8 alarms;              /* alarm register value */
  76 };
  77
  78 static struct adc128_data *adc128_update_device(struct device *dev)
  79 {
  80         struct adc128_data *data = dev_get_drvdata(dev);
  81         struct i2c_client *client = data->client;
  82         struct adc128_data *ret = data;
  83         int i, rv;
  84
  85         mutex_lock(&data->update_lock);
  86
  87         if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
  88                 for (i = 0; i < num_inputs[data->mode]; i++) {
  89                         rv = i2c_smbus_read_word_swapped(client,
  90                                                          ADC128_REG_IN(i));
  91                         if (rv < 0)
  92                                 goto abort;
  93                         data->in[0][i] = rv >> 4;
  94
  95                         rv = i2c_smbus_read_byte_data(client,
  96                                                       ADC128_REG_IN_MIN(i));
  97                         if (rv < 0)
  98                                 goto abort;
  99                         data->in[1][i] = rv << 4;
 100
 101                         rv = i2c_smbus_read_byte_data(client,
 102                                                       ADC128_REG_IN_MAX(i));
 103                         if (rv < 0)
 104                                 goto abort;
 105                         data->in[2][i] = rv << 4;
 106                 }
 107
 108                 if (data->mode != 1) {
 109                         rv = i2c_smbus_read_word_swapped(client,
 110                                                          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,
 116                                                       ADC128_REG_TEMP_MAX);
 117                         if (rv < 0)
 118                                 goto abort;
 119                         data->temp[1] = rv << 1;
 120
 121                         rv = i2c_smbus_read_byte_data(client,
 122                                                       ADC128_REG_TEMP_HYST);
 123                         if (rv < 0)
 124                                 goto abort;
 125                         data->temp[2] = rv << 1;
 126                 }
 127
 128                 rv = i2c_smbus_read_byte_data(client, ADC128_REG_ALARM);
 129                 if (rv < 0)
 130                         goto abort;
 131                 data->alarms |= rv;
 132
 133                 data->last_updated = jiffies;
 134                 data->valid = true;
 135         }
 136         goto done;
 137
 138 abort:
 139         ret = ERR_PTR(rv);
 140         data->valid = false;
 141 done:
 142         mutex_unlock(&data->update_lock);
 143         return ret;
 144 }
 145
 146 static ssize_t adc128_in_show(struct device *dev,
 147                               struct device_attribute *attr, char *buf)
 148 {
 149         struct adc128_data *data = adc128_update_device(dev);
 150         int index = to_sensor_dev_attr_2(attr)->index;
 151         int nr = to_sensor_dev_attr_2(attr)->nr;
 152         int val;
 153
 154         if (IS_ERR(data))
 155                 return PTR_ERR(data);
 156
 157         val = DIV_ROUND_CLOSEST(data->in[index][nr] * data->vref, 4095);
 158         return sprintf(buf, "%d\n", val);
 159 }
 160
 161 static ssize_t adc128_in_store(struct device *dev,
 162                                struct device_attribute *attr, const char *buf,
 163                                size_t count)
 164 {
 165         struct adc128_data *data = dev_get_drvdata(dev);
 166         int index = to_sensor_dev_attr_2(attr)->index;
 167         int nr = to_sensor_dev_attr_2(attr)->nr;
 168         u8 reg, regval;
 169         long val;
 170         int err;
 171
 172         err = kstrtol(buf, 10, &val);
 173         if (err < 0)
 174                 return err;
 175
 176         mutex_lock(&data->update_lock);
 177         /* 10 mV LSB on limit registers */
 178         regval = DIV_ROUND_CLOSEST(clamp_val(val, 0, 2550), 10);
 179         data->in[index][nr] = regval << 4;
 180         reg = index == 1 ? ADC128_REG_IN_MIN(nr) : ADC128_REG_IN_MAX(nr);
 181         i2c_smbus_write_byte_data(data->client, reg, regval);
 182         mutex_unlock(&data->update_lock);
 183
 184         return count;
 185 }
 186
 187 static ssize_t adc128_temp_show(struct device *dev,
 188                                 struct device_attribute *attr, char *buf)
 189 {
 190         struct adc128_data *data = adc128_update_device(dev);
 191         int index = to_sensor_dev_attr(attr)->index;
 192         int temp;
 193
 194         if (IS_ERR(data))
 195                 return PTR_ERR(data);
 196
 197         temp = sign_extend32(data->temp[index], 8);
 198         return sprintf(buf, "%d\n", temp * 500);/* 0.5 degrees C resolution */
 199 }
 200
 201 static ssize_t adc128_temp_store(struct device *dev,
 202                                  struct device_attribute *attr,
 203                                  const char *buf, size_t count)
 204 {
 205         struct adc128_data *data = dev_get_drvdata(dev);
 206         int index = to_sensor_dev_attr(attr)->index;
 207         long val;
 208         int err;
 209         s8 regval;
 210
 211         err = kstrtol(buf, 10, &val);
 212         if (err < 0)
 213                 return err;
 214
 215         mutex_lock(&data->update_lock);
 216         regval = DIV_ROUND_CLOSEST(clamp_val(val, -128000, 127000), 1000);
 217         data->temp[index] = regval << 1;
 218         i2c_smbus_write_byte_data(data->client,
 219                                   index == 1 ? ADC128_REG_TEMP_MAX
 220                                              : ADC128_REG_TEMP_HYST,
 221                                   regval);
 222         mutex_unlock(&data->update_lock);
 223
 224         return count;
 225 }
 226
 227 static ssize_t adc128_alarm_show(struct device *dev,
 228                                  struct device_attribute *attr, char *buf)
 229 {
 230         struct adc128_data *data = adc128_update_device(dev);
 231         int mask = 1 << to_sensor_dev_attr(attr)->index;
 232         u8 alarms;
 233
 234         if (IS_ERR(data))
 235                 return PTR_ERR(data);
 236
 237         /*
 238          * Clear an alarm after reporting it to user space. If it is still
 239          * active, the next update sequence will set the alarm bit again.
 240          */
 241         alarms = data->alarms;
 242         data->alarms &= ~mask;
 243
 244         return sprintf(buf, "%u\n", !!(alarms & mask));
 245 }
 246
 247 static umode_t adc128_is_visible(struct kobject *kobj,
 248                                  struct attribute *attr, int index)
 249 {
 250         struct device *dev = kobj_to_dev(kobj);
 251         struct adc128_data *data = dev_get_drvdata(dev);
 252
 253         if (index < ADC128_ATTR_NUM_VOLT) {
 254                 /* Voltage, visible according to num_inputs[] */
 255                 if (index >= num_inputs[data->mode] * 4)
 256                         return 0;
 257         } else {
 258                 /* Temperature, visible if not in mode 1 */
 259                 if (data->mode == 1)
 260                         return 0;
 261         }
 262
 263         return attr->mode;
 264 }
 265
 266 static SENSOR_DEVICE_ATTR_2_RO(in0_input, adc128_in, 0, 0);
 267 static SENSOR_DEVICE_ATTR_2_RW(in0_min, adc128_in, 0, 1);
 268 static SENSOR_DEVICE_ATTR_2_RW(in0_max, adc128_in, 0, 2);
 269
 270 static SENSOR_DEVICE_ATTR_2_RO(in1_input, adc128_in, 1, 0);
 271 static SENSOR_DEVICE_ATTR_2_RW(in1_min, adc128_in, 1, 1);
 272 static SENSOR_DEVICE_ATTR_2_RW(in1_max, adc128_in, 1, 2);
 273
 274 static SENSOR_DEVICE_ATTR_2_RO(in2_input, adc128_in, 2, 0);
 275 static SENSOR_DEVICE_ATTR_2_RW(in2_min, adc128_in, 2, 1);
 276 static SENSOR_DEVICE_ATTR_2_RW(in2_max, adc128_in, 2, 2);
 277
 278 static SENSOR_DEVICE_ATTR_2_RO(in3_input, adc128_in, 3, 0);
 279 static SENSOR_DEVICE_ATTR_2_RW(in3_min, adc128_in, 3, 1);
 280 static SENSOR_DEVICE_ATTR_2_RW(in3_max, adc128_in, 3, 2);
 281
 282 static SENSOR_DEVICE_ATTR_2_RO(in4_input, adc128_in, 4, 0);
 283 static SENSOR_DEVICE_ATTR_2_RW(in4_min, adc128_in, 4, 1);
 284 static SENSOR_DEVICE_ATTR_2_RW(in4_max, adc128_in, 4, 2);
 285
 286 static SENSOR_DEVICE_ATTR_2_RO(in5_input, adc128_in, 5, 0);
 287 static SENSOR_DEVICE_ATTR_2_RW(in5_min, adc128_in, 5, 1);
 288 static SENSOR_DEVICE_ATTR_2_RW(in5_max, adc128_in, 5, 2);
 289
 290 static SENSOR_DEVICE_ATTR_2_RO(in6_input, adc128_in, 6, 0);
 291 static SENSOR_DEVICE_ATTR_2_RW(in6_min, adc128_in, 6, 1);
 292 static SENSOR_DEVICE_ATTR_2_RW(in6_max, adc128_in, 6, 2);
 293
 294 static SENSOR_DEVICE_ATTR_2_RO(in7_input, adc128_in, 7, 0);
 295 static SENSOR_DEVICE_ATTR_2_RW(in7_min, adc128_in, 7, 1);
 296 static SENSOR_DEVICE_ATTR_2_RW(in7_max, adc128_in, 7, 2);
 297
 298 static SENSOR_DEVICE_ATTR_RO(temp1_input, adc128_temp, 0);
 299 static SENSOR_DEVICE_ATTR_RW(temp1_max, adc128_temp, 1);
 300 static SENSOR_DEVICE_ATTR_RW(temp1_max_hyst, adc128_temp, 2);
 301
 302 static SENSOR_DEVICE_ATTR_RO(in0_alarm, adc128_alarm, 0);
 303 static SENSOR_DEVICE_ATTR_RO(in1_alarm, adc128_alarm, 1);
 304 static SENSOR_DEVICE_ATTR_RO(in2_alarm, adc128_alarm, 2);
 305 static SENSOR_DEVICE_ATTR_RO(in3_alarm, adc128_alarm, 3);
 306 static SENSOR_DEVICE_ATTR_RO(in4_alarm, adc128_alarm, 4);
 307 static SENSOR_DEVICE_ATTR_RO(in5_alarm, adc128_alarm, 5);
 308 static SENSOR_DEVICE_ATTR_RO(in6_alarm, adc128_alarm, 6);
 309 static SENSOR_DEVICE_ATTR_RO(in7_alarm, adc128_alarm, 7);
 310 static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, adc128_alarm, 7);
 311
 312 static struct attribute *adc128_attrs[] = {
 313         &sensor_dev_attr_in0_alarm.dev_attr.attr,
 314         &sensor_dev_attr_in0_input.dev_attr.attr,
 315         &sensor_dev_attr_in0_max.dev_attr.attr,
 316         &sensor_dev_attr_in0_min.dev_attr.attr,
 317         &sensor_dev_attr_in1_alarm.dev_attr.attr,
 318         &sensor_dev_attr_in1_input.dev_attr.attr,
 319         &sensor_dev_attr_in1_max.dev_attr.attr,
 320         &sensor_dev_attr_in1_min.dev_attr.attr,
 321         &sensor_dev_attr_in2_alarm.dev_attr.attr,
 322         &sensor_dev_attr_in2_input.dev_attr.attr,
 323         &sensor_dev_attr_in2_max.dev_attr.attr,
 324         &sensor_dev_attr_in2_min.dev_attr.attr,
 325         &sensor_dev_attr_in3_alarm.dev_attr.attr,
 326         &sensor_dev_attr_in3_input.dev_attr.attr,
 327         &sensor_dev_attr_in3_max.dev_attr.attr,
 328         &sensor_dev_attr_in3_min.dev_attr.attr,
 329         &sensor_dev_attr_in4_alarm.dev_attr.attr,
 330         &sensor_dev_attr_in4_input.dev_attr.attr,
 331         &sensor_dev_attr_in4_max.dev_attr.attr,
 332         &sensor_dev_attr_in4_min.dev_attr.attr,
 333         &sensor_dev_attr_in5_alarm.dev_attr.attr,
 334         &sensor_dev_attr_in5_input.dev_attr.attr,
 335         &sensor_dev_attr_in5_max.dev_attr.attr,
 336         &sensor_dev_attr_in5_min.dev_attr.attr,
 337         &sensor_dev_attr_in6_alarm.dev_attr.attr,
 338         &sensor_dev_attr_in6_input.dev_attr.attr,
 339         &sensor_dev_attr_in6_max.dev_attr.attr,
 340         &sensor_dev_attr_in6_min.dev_attr.attr,
 341         &sensor_dev_attr_in7_alarm.dev_attr.attr,
 342         &sensor_dev_attr_in7_input.dev_attr.attr,
 343         &sensor_dev_attr_in7_max.dev_attr.attr,
 344         &sensor_dev_attr_in7_min.dev_attr.attr,
 345         &sensor_dev_attr_temp1_input.dev_attr.attr,
 346         &sensor_dev_attr_temp1_max.dev_attr.attr,
 347         &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 348         &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
 349         NULL
 350 };
 351
 352 static const struct attribute_group adc128_group = {
 353         .attrs = adc128_attrs,
 354         .is_visible = adc128_is_visible,
 355 };
 356 __ATTRIBUTE_GROUPS(adc128);
 357
 358 static int adc128_detect(struct i2c_client *client, struct i2c_board_info *info)
 359 {
 360         int man_id, dev_id;
 361
 362         if (!i2c_check_functionality(client->adapter,
 363                                      I2C_FUNC_SMBUS_BYTE_DATA |
 364                                      I2C_FUNC_SMBUS_WORD_DATA))
 365                 return -ENODEV;
 366
 367         man_id = i2c_smbus_read_byte_data(client, ADC128_REG_MAN_ID);
 368         dev_id = i2c_smbus_read_byte_data(client, ADC128_REG_DEV_ID);
 369         if (man_id != 0x01 || dev_id != 0x09)
 370                 return -ENODEV;
 371
 372         /* Check unused bits for confirmation */
 373         if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG) & 0xf4)
 374                 return -ENODEV;
 375         if (i2c_smbus_read_byte_data(client, ADC128_REG_CONV_RATE) & 0xfe)
 376                 return -ENODEV;
 377         if (i2c_smbus_read_byte_data(client, ADC128_REG_ONESHOT) & 0xfe)
 378                 return -ENODEV;
 379         if (i2c_smbus_read_byte_data(client, ADC128_REG_SHUTDOWN) & 0xfe)
 380                 return -ENODEV;
 381         if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV) & 0xf8)
 382                 return -ENODEV;
 383         if (i2c_smbus_read_byte_data(client, ADC128_REG_BUSY_STATUS) & 0xfc)
 384                 return -ENODEV;
 385
 386         strscpy(info->type, "adc128d818", I2C_NAME_SIZE);
 387
 388         return 0;
 389 }
 390
 391 static int adc128_init_client(struct adc128_data *data, bool external_vref)
 392 {
 393         struct i2c_client *client = data->client;
 394         int err;
 395         u8 regval = 0x0;
 396
 397         /*
 398          * Reset chip to defaults.
 399          * This makes most other initializations unnecessary.
 400          */
 401         err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x80);
 402         if (err)
 403                 return err;
 404
 405         /* Set operation mode, if non-default */
 406         if (data->mode != 0)
 407                 regval |= data->mode << 1;
 408
 409         /* If external vref is selected, configure the chip to use it */
 410         if (external_vref)
 411                 regval |= 0x01;
 412
 413         /* Write advanced configuration register */
 414         if (regval != 0x0) {
 415                 err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG_ADV,
 416                                                 regval);
 417                 if (err)
 418                         return err;
 419         }
 420
 421         /* Start monitoring */
 422         err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x01);
 423         if (err)
 424                 return err;
 425
 426         return 0;
 427 }
 428
 429 static int adc128_probe(struct i2c_client *client)
 430 {
 431         struct device *dev = &client->dev;
 432         struct device *hwmon_dev;
 433         struct adc128_data *data;
 434         bool external_vref;
 435         int err, vref;
 436
 437         data = devm_kzalloc(dev, sizeof(struct adc128_data), GFP_KERNEL);
 438         if (!data)
 439                 return -ENOMEM;
 440
 441         /* vref is optional. If specified, is used as chip reference voltage */
 442         vref = devm_regulator_get_enable_read_voltage(dev, "vref");
 443         if (vref == -ENODEV) {
 444                 external_vref = false;
 445                 data->vref = 2560;      /* 2.56V, in mV */
 446         } else if (vref < 0) {
 447                 return vref;
 448         } else {
 449                 external_vref = true;
 450                 data->vref = DIV_ROUND_CLOSEST(vref, 1000);
 451         }
 452
 453         /* Operation mode is optional. If unspecified, keep current mode */
 454         if (of_property_read_u8(dev->of_node, "ti,mode", &data->mode) == 0) {
 455                 if (data->mode > 3) {
 456                         dev_err(dev, "invalid operation mode %d\n",
 457                                 data->mode);
 458                         return -EINVAL;
 459                 }
 460         } else {
 461                 err = i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV);
 462                 if (err < 0)
 463                         return err;
 464                 data->mode = (err >> 1) & ADC128_REG_MASK;
 465         }
 466
 467         data->client = client;
 468         i2c_set_clientdata(client, data);
 469         mutex_init(&data->update_lock);
 470
 471         /* Initialize the chip */
 472         err = adc128_init_client(data, external_vref);
 473         if (err < 0)
 474                 return err;
 475
 476         hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
 477                                                            data, adc128_groups);
 478
 479         return PTR_ERR_OR_ZERO(hwmon_dev);
 480 }
 481
 482 static const struct i2c_device_id adc128_id[] = {
 483         { "adc128d818" },
 484         { }
 485 };
 486 MODULE_DEVICE_TABLE(i2c, adc128_id);
 487
 488 static const struct of_device_id __maybe_unused adc128_of_match[] = {
 489         { .compatible = "ti,adc128d818" },
 490         { },
 491 };
 492 MODULE_DEVICE_TABLE(of, adc128_of_match);
 493
 494 static struct i2c_driver adc128_driver = {
 495         .class          = I2C_CLASS_HWMON,
 496         .driver = {
 497                 .name   = "adc128d818",
 498                 .of_match_table = of_match_ptr(adc128_of_match),
 499         },
 500         .probe          = adc128_probe,
 501         .id_table       = adc128_id,
 502         .detect         = adc128_detect,
 503         .address_list   = normal_i2c,
 504 };
 505
 506 module_i2c_driver(adc128_driver);
 507
 508 MODULE_AUTHOR("Guenter Roeck");
 509 MODULE_DESCRIPTION("Driver for ADC128D818");
 510 MODULE_LICENSE("GPL");