LXR linux/drivers/hwmon/lm83.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * lm83.c - Part of lm_sensors, Linux kernel modules for hardware
   4 *          monitoring
   5 * Copyright (C) 2003-2009  Jean Delvare <jdelvare@suse.de>
   6 *
   7 * Heavily inspired from the lm78, lm75 and adm1021 drivers. The LM83 is
   8 * a sensor chip made by National Semiconductor. It reports up to four
   9 * temperatures (its own plus up to three external ones) with a 1 deg
  10 * resolution and a 3-4 deg accuracy. Complete datasheet can be obtained
  11 * from National's website at:
  12 *   http://www.national.com/pf/LM/LM83.html
  13 * Since the datasheet omits to give the chip stepping code, I give it
  14 * here: 0x03 (at register 0xff).
  15 *
  16 * Also supports the LM82 temp sensor, which is basically a stripped down
  17 * model of the LM83.  Datasheet is here:
  18 * http://www.national.com/pf/LM/LM82.html
  19 */
  20
  21#include <linux/module.h>
  22#include <linux/init.h>
  23#include <linux/slab.h>
  24#include <linux/jiffies.h>
  25#include <linux/i2c.h>
  26#include <linux/hwmon-sysfs.h>
  27#include <linux/hwmon.h>
  28#include <linux/err.h>
  29#include <linux/mutex.h>
  30#include <linux/sysfs.h>
  31
  32/*
  33 * Addresses to scan
  34 * Address is selected using 2 three-level pins, resulting in 9 possible
  35 * addresses.
  36 */
  37
  38static const unsigned short normal_i2c[] = {
  39        0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
  40
  41enum chips { lm83, lm82 };
  42
  43/*
  44 * The LM83 registers
  45 * Manufacturer ID is 0x01 for National Semiconductor.
  46 */
  47
  48#define LM83_REG_R_MAN_ID               0xFE
  49#define LM83_REG_R_CHIP_ID              0xFF
  50#define LM83_REG_R_CONFIG               0x03
  51#define LM83_REG_W_CONFIG               0x09
  52#define LM83_REG_R_STATUS1              0x02
  53#define LM83_REG_R_STATUS2              0x35
  54#define LM83_REG_R_LOCAL_TEMP           0x00
  55#define LM83_REG_R_LOCAL_HIGH           0x05
  56#define LM83_REG_W_LOCAL_HIGH           0x0B
  57#define LM83_REG_R_REMOTE1_TEMP         0x30
  58#define LM83_REG_R_REMOTE1_HIGH         0x38
  59#define LM83_REG_W_REMOTE1_HIGH         0x50
  60#define LM83_REG_R_REMOTE2_TEMP         0x01
  61#define LM83_REG_R_REMOTE2_HIGH         0x07
  62#define LM83_REG_W_REMOTE2_HIGH         0x0D
  63#define LM83_REG_R_REMOTE3_TEMP         0x31
  64#define LM83_REG_R_REMOTE3_HIGH         0x3A
  65#define LM83_REG_W_REMOTE3_HIGH         0x52
  66#define LM83_REG_R_TCRIT                0x42
  67#define LM83_REG_W_TCRIT                0x5A
  68
  69/*
  70 * Conversions and various macros
  71 * The LM83 uses signed 8-bit values with LSB = 1 degree Celsius.
  72 */
  73
  74#define TEMP_FROM_REG(val)      ((val) * 1000)
  75#define TEMP_TO_REG(val)        ((val) <= -128000 ? -128 : \
  76                                 (val) >= 127000 ? 127 : \
  77                                 (val) < 0 ? ((val) - 500) / 1000 : \
  78                                 ((val) + 500) / 1000)
  79
  80static const u8 LM83_REG_R_TEMP[] = {
  81        LM83_REG_R_LOCAL_TEMP,
  82        LM83_REG_R_REMOTE1_TEMP,
  83        LM83_REG_R_REMOTE2_TEMP,
  84        LM83_REG_R_REMOTE3_TEMP,
  85        LM83_REG_R_LOCAL_HIGH,
  86        LM83_REG_R_REMOTE1_HIGH,
  87        LM83_REG_R_REMOTE2_HIGH,
  88        LM83_REG_R_REMOTE3_HIGH,
  89        LM83_REG_R_TCRIT,
  90};
  91
  92static const u8 LM83_REG_W_HIGH[] = {
  93        LM83_REG_W_LOCAL_HIGH,
  94        LM83_REG_W_REMOTE1_HIGH,
  95        LM83_REG_W_REMOTE2_HIGH,
  96        LM83_REG_W_REMOTE3_HIGH,
  97        LM83_REG_W_TCRIT,
  98};
  99
 100/*
 101 * Client data (each client gets its own)
 102 */
 103
 104struct lm83_data {
 105        struct i2c_client *client;
 106        const struct attribute_group *groups[3];
 107        struct mutex update_lock;
 108        char valid; /* zero until following fields are valid */
 109        unsigned long last_updated; /* in jiffies */
 110
 111        /* registers values */
 112        s8 temp[9];     /* 0..3: input 1-4,
 113                           4..7: high limit 1-4,
 114                           8   : critical limit */
 115        u16 alarms; /* bitvector, combined */
 116};
 117
 118static struct lm83_data *lm83_update_device(struct device *dev)
 119{
 120        struct lm83_data *data = dev_get_drvdata(dev);
 121        struct i2c_client *client = data->client;
 122
 123        mutex_lock(&data->update_lock);
 124
 125        if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
 126                int nr;
 127
 128                dev_dbg(&client->dev, "Updating lm83 data.\n");
 129                for (nr = 0; nr < 9; nr++) {
 130                        data->temp[nr] =
 131                            i2c_smbus_read_byte_data(client,
 132                            LM83_REG_R_TEMP[nr]);
 133                }
 134                data->alarms =
 135                    i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1)
 136                    + (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2)
 137                    << 8);
 138
 139                data->last_updated = jiffies;
 140                data->valid = 1;
 141        }
 142
 143        mutex_unlock(&data->update_lock);
 144
 145        return data;
 146}
 147
 148/*
 149 * Sysfs stuff
 150 */
 151
 152static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
 153                         char *buf)
 154{
 155        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 156        struct lm83_data *data = lm83_update_device(dev);
 157        return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]));
 158}
 159
 160static ssize_t temp_store(struct device *dev,
 161                          struct device_attribute *devattr, const char *buf,
 162                          size_t count)
 163{
 164        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 165        struct lm83_data *data = dev_get_drvdata(dev);
 166        struct i2c_client *client = data->client;
 167        long val;
 168        int nr = attr->index;
 169        int err;
 170
 171        err = kstrtol(buf, 10, &val);
 172        if (err < 0)
 173                return err;
 174
 175        mutex_lock(&data->update_lock);
 176        data->temp[nr] = TEMP_TO_REG(val);
 177        i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr - 4],
 178                                  data->temp[nr]);
 179        mutex_unlock(&data->update_lock);
 180        return count;
 181}
 182
 183static ssize_t alarms_show(struct device *dev, struct device_attribute *dummy,
 184                           char *buf)
 185{
 186        struct lm83_data *data = lm83_update_device(dev);
 187        return sprintf(buf, "%d\n", data->alarms);
 188}
 189
 190static ssize_t alarm_show(struct device *dev,
 191                          struct device_attribute *devattr, char *buf)
 192{
 193        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 194        struct lm83_data *data = lm83_update_device(dev);
 195        int bitnr = attr->index;
 196
 197        return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
 198}
 199
 200static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, 0);
 201static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, 1);
 202static SENSOR_DEVICE_ATTR_RO(temp3_input, temp, 2);
 203static SENSOR_DEVICE_ATTR_RO(temp4_input, temp, 3);
 204static SENSOR_DEVICE_ATTR_RW(temp1_max, temp, 4);
 205static SENSOR_DEVICE_ATTR_RW(temp2_max, temp, 5);
 206static SENSOR_DEVICE_ATTR_RW(temp3_max, temp, 6);
 207static SENSOR_DEVICE_ATTR_RW(temp4_max, temp, 7);
 208static SENSOR_DEVICE_ATTR_RO(temp1_crit, temp, 8);
 209static SENSOR_DEVICE_ATTR_RO(temp2_crit, temp, 8);
 210static SENSOR_DEVICE_ATTR_RW(temp3_crit, temp, 8);
 211static SENSOR_DEVICE_ATTR_RO(temp4_crit, temp, 8);
 212
 213/* Individual alarm files */
 214static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, alarm, 0);
 215static SENSOR_DEVICE_ATTR_RO(temp3_crit_alarm, alarm, 1);
 216static SENSOR_DEVICE_ATTR_RO(temp3_fault, alarm, 2);
 217static SENSOR_DEVICE_ATTR_RO(temp3_max_alarm, alarm, 4);
 218static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, alarm, 6);
 219static SENSOR_DEVICE_ATTR_RO(temp2_crit_alarm, alarm, 8);
 220static SENSOR_DEVICE_ATTR_RO(temp4_crit_alarm, alarm, 9);
 221static SENSOR_DEVICE_ATTR_RO(temp4_fault, alarm, 10);
 222static SENSOR_DEVICE_ATTR_RO(temp4_max_alarm, alarm, 12);
 223static SENSOR_DEVICE_ATTR_RO(temp2_fault, alarm, 13);
 224static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, alarm, 15);
 225/* Raw alarm file for compatibility */
 226static DEVICE_ATTR_RO(alarms);
 227
 228static struct attribute *lm83_attributes[] = {
 229        &sensor_dev_attr_temp1_input.dev_attr.attr,
 230        &sensor_dev_attr_temp3_input.dev_attr.attr,
 231        &sensor_dev_attr_temp1_max.dev_attr.attr,
 232        &sensor_dev_attr_temp3_max.dev_attr.attr,
 233        &sensor_dev_attr_temp1_crit.dev_attr.attr,
 234        &sensor_dev_attr_temp3_crit.dev_attr.attr,
 235
 236        &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
 237        &sensor_dev_attr_temp3_crit_alarm.dev_attr.attr,
 238        &sensor_dev_attr_temp3_fault.dev_attr.attr,
 239        &sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
 240        &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 241        &dev_attr_alarms.attr,
 242        NULL
 243};
 244
 245static const struct attribute_group lm83_group = {
 246        .attrs = lm83_attributes,
 247};
 248
 249static struct attribute *lm83_attributes_opt[] = {
 250        &sensor_dev_attr_temp2_input.dev_attr.attr,
 251        &sensor_dev_attr_temp4_input.dev_attr.attr,
 252        &sensor_dev_attr_temp2_max.dev_attr.attr,
 253        &sensor_dev_attr_temp4_max.dev_attr.attr,
 254        &sensor_dev_attr_temp2_crit.dev_attr.attr,
 255        &sensor_dev_attr_temp4_crit.dev_attr.attr,
 256
 257        &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
 258        &sensor_dev_attr_temp4_crit_alarm.dev_attr.attr,
 259        &sensor_dev_attr_temp4_fault.dev_attr.attr,
 260        &sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
 261        &sensor_dev_attr_temp2_fault.dev_attr.attr,
 262        &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
 263        NULL
 264};
 265
 266static const struct attribute_group lm83_group_opt = {
 267        .attrs = lm83_attributes_opt,
 268};
 269
 270/*
 271 * Real code
 272 */
 273
 274/* Return 0 if detection is successful, -ENODEV otherwise */
 275static int lm83_detect(struct i2c_client *new_client,
 276                       struct i2c_board_info *info)
 277{
 278        struct i2c_adapter *adapter = new_client->adapter;
 279        const char *name;
 280        u8 man_id, chip_id;
 281
 282        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 283                return -ENODEV;
 284
 285        /* Detection */
 286        if ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1) & 0xA8) ||
 287            (i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2) & 0x48) ||
 288            (i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG) & 0x41)) {
 289                dev_dbg(&adapter->dev, "LM83 detection failed at 0x%02x\n",
 290                        new_client->addr);
 291                return -ENODEV;
 292        }
 293
 294        /* Identification */
 295        man_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_MAN_ID);
 296        if (man_id != 0x01)     /* National Semiconductor */
 297                return -ENODEV;
 298
 299        chip_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_CHIP_ID);
 300        switch (chip_id) {
 301        case 0x03:
 302                name = "lm83";
 303                break;
 304        case 0x01:
 305                name = "lm82";
 306                break;
 307        default:
 308                /* identification failed */
 309                dev_info(&adapter->dev,
 310                         "Unsupported chip (man_id=0x%02X, chip_id=0x%02X)\n",
 311                         man_id, chip_id);
 312                return -ENODEV;
 313        }
 314
 315        strlcpy(info->type, name, I2C_NAME_SIZE);
 316
 317        return 0;
 318}
 319
 320static const struct i2c_device_id lm83_id[];
 321
 322static int lm83_probe(struct i2c_client *new_client)
 323{
 324        struct device *hwmon_dev;
 325        struct lm83_data *data;
 326
 327        data = devm_kzalloc(&new_client->dev, sizeof(struct lm83_data),
 328                            GFP_KERNEL);
 329        if (!data)
 330                return -ENOMEM;
 331
 332        data->client = new_client;
 333        mutex_init(&data->update_lock);
 334
 335        /*
 336         * Register sysfs hooks
 337         * The LM82 can only monitor one external diode which is
 338         * at the same register as the LM83 temp3 entry - so we
 339         * declare 1 and 3 common, and then 2 and 4 only for the LM83.
 340         */
 341        data->groups[0] = &lm83_group;
 342        if (i2c_match_id(lm83_id, new_client)->driver_data == lm83)
 343                data->groups[1] = &lm83_group_opt;
 344
 345        hwmon_dev = devm_hwmon_device_register_with_groups(&new_client->dev,
 346                                                           new_client->name,
 347                                                           data, data->groups);
 348        return PTR_ERR_OR_ZERO(hwmon_dev);
 349}
 350
 351/*
 352 * Driver data (common to all clients)
 353 */
 354
 355static const struct i2c_device_id lm83_id[] = {
 356        { "lm83", lm83 },
 357        { "lm82", lm82 },
 358        { }
 359};
 360MODULE_DEVICE_TABLE(i2c, lm83_id);
 361
 362static struct i2c_driver lm83_driver = {
 363        .class          = I2C_CLASS_HWMON,
 364        .driver = {
 365                .name   = "lm83",
 366        },
 367        .probe_new      = lm83_probe,
 368        .id_table       = lm83_id,
 369        .detect         = lm83_detect,
 370        .address_list   = normal_i2c,
 371};
 372
 373module_i2c_driver(lm83_driver);
 374
 375MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
 376MODULE_DESCRIPTION("LM83 driver");
 377MODULE_LICENSE("GPL");
 378