linux/drivers/hwmon/adc128d818.c
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   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 */
  29static 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 */
  57static const u8 num_inputs[] = { 7, 8, 4, 6 };
  58
  59struct 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
  79static 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
 139abort:
 140        ret = ERR_PTR(rv);
 141        data->valid = false;
 142done:
 143        mutex_unlock(&data->update_lock);
 144        return ret;
 145}
 146
 147static 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
 162static 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
 188static 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
 202static 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
 228static 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
 248static 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
 267static SENSOR_DEVICE_ATTR_2_RO(in0_input, adc128_in, 0, 0);
 268static SENSOR_DEVICE_ATTR_2_RW(in0_min, adc128_in, 0, 1);
 269static SENSOR_DEVICE_ATTR_2_RW(in0_max, adc128_in, 0, 2);
 270
 271static SENSOR_DEVICE_ATTR_2_RO(in1_input, adc128_in, 1, 0);
 272static SENSOR_DEVICE_ATTR_2_RW(in1_min, adc128_in, 1, 1);
 273static SENSOR_DEVICE_ATTR_2_RW(in1_max, adc128_in, 1, 2);
 274
 275static SENSOR_DEVICE_ATTR_2_RO(in2_input, adc128_in, 2, 0);
 276static SENSOR_DEVICE_ATTR_2_RW(in2_min, adc128_in, 2, 1);
 277static SENSOR_DEVICE_ATTR_2_RW(in2_max, adc128_in, 2, 2);
 278
 279static SENSOR_DEVICE_ATTR_2_RO(in3_input, adc128_in, 3, 0);
 280static SENSOR_DEVICE_ATTR_2_RW(in3_min, adc128_in, 3, 1);
 281static SENSOR_DEVICE_ATTR_2_RW(in3_max, adc128_in, 3, 2);
 282
 283static SENSOR_DEVICE_ATTR_2_RO(in4_input, adc128_in, 4, 0);
 284static SENSOR_DEVICE_ATTR_2_RW(in4_min, adc128_in, 4, 1);
 285static SENSOR_DEVICE_ATTR_2_RW(in4_max, adc128_in, 4, 2);
 286
 287static SENSOR_DEVICE_ATTR_2_RO(in5_input, adc128_in, 5, 0);
 288static SENSOR_DEVICE_ATTR_2_RW(in5_min, adc128_in, 5, 1);
 289static SENSOR_DEVICE_ATTR_2_RW(in5_max, adc128_in, 5, 2);
 290
 291static SENSOR_DEVICE_ATTR_2_RO(in6_input, adc128_in, 6, 0);
 292static SENSOR_DEVICE_ATTR_2_RW(in6_min, adc128_in, 6, 1);
 293static SENSOR_DEVICE_ATTR_2_RW(in6_max, adc128_in, 6, 2);
 294
 295static SENSOR_DEVICE_ATTR_2_RO(in7_input, adc128_in, 7, 0);
 296static SENSOR_DEVICE_ATTR_2_RW(in7_min, adc128_in, 7, 1);
 297static SENSOR_DEVICE_ATTR_2_RW(in7_max, adc128_in, 7, 2);
 298
 299static SENSOR_DEVICE_ATTR_RO(temp1_input, adc128_temp, 0);
 300static SENSOR_DEVICE_ATTR_RW(temp1_max, adc128_temp, 1);
 301static SENSOR_DEVICE_ATTR_RW(temp1_max_hyst, adc128_temp, 2);
 302
 303static SENSOR_DEVICE_ATTR_RO(in0_alarm, adc128_alarm, 0);
 304static SENSOR_DEVICE_ATTR_RO(in1_alarm, adc128_alarm, 1);
 305static SENSOR_DEVICE_ATTR_RO(in2_alarm, adc128_alarm, 2);
 306static SENSOR_DEVICE_ATTR_RO(in3_alarm, adc128_alarm, 3);
 307static SENSOR_DEVICE_ATTR_RO(in4_alarm, adc128_alarm, 4);
 308static SENSOR_DEVICE_ATTR_RO(in5_alarm, adc128_alarm, 5);
 309static SENSOR_DEVICE_ATTR_RO(in6_alarm, adc128_alarm, 6);
 310static SENSOR_DEVICE_ATTR_RO(in7_alarm, adc128_alarm, 7);
 311static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, adc128_alarm, 7);
 312
 313static 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
 353static const struct attribute_group adc128_group = {
 354        .attrs = adc128_attrs,
 355        .is_visible = adc128_is_visible,
 356};
 357__ATTRIBUTE_GROUPS(adc128);
 358
 359static 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        strlcpy(info->type, "adc128d818", I2C_NAME_SIZE);
 388
 389        return 0;
 390}
 391
 392static 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
 430static 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
 492error:
 493        if (data->regulator)
 494                regulator_disable(data->regulator);
 495        return err;
 496}
 497
 498static int 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        return 0;
 506}
 507
 508static const struct i2c_device_id adc128_id[] = {
 509        { "adc128d818", 0 },
 510        { }
 511};
 512MODULE_DEVICE_TABLE(i2c, adc128_id);
 513
 514static const struct of_device_id __maybe_unused adc128_of_match[] = {
 515        { .compatible = "ti,adc128d818" },
 516        { },
 517};
 518MODULE_DEVICE_TABLE(of, adc128_of_match);
 519
 520static struct i2c_driver adc128_driver = {
 521        .class          = I2C_CLASS_HWMON,
 522        .driver = {
 523                .name   = "adc128d818",
 524                .of_match_table = of_match_ptr(adc128_of_match),
 525        },
 526        .probe_new      = adc128_probe,
 527        .remove         = adc128_remove,
 528        .id_table       = adc128_id,
 529        .detect         = adc128_detect,
 530        .address_list   = normal_i2c,
 531};
 532
 533module_i2c_driver(adc128_driver);
 534
 535MODULE_AUTHOR("Guenter Roeck");
 536MODULE_DESCRIPTION("Driver for ADC128D818");
 537MODULE_LICENSE("GPL");
 538