linux/drivers/hwmon/lm83.c
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   1/*
   2 * lm83.c - Part of lm_sensors, Linux kernel modules for hardware
   3 *          monitoring
   4 * Copyright (C) 2003-2009  Jean Delvare <khali@linux-fr.org>
   5 *
   6 * Heavily inspired from the lm78, lm75 and adm1021 drivers. The LM83 is
   7 * a sensor chip made by National Semiconductor. It reports up to four
   8 * temperatures (its own plus up to three external ones) with a 1 deg
   9 * resolution and a 3-4 deg accuracy. Complete datasheet can be obtained
  10 * from National's website at:
  11 *   http://www.national.com/pf/LM/LM83.html
  12 * Since the datasheet omits to give the chip stepping code, I give it
  13 * here: 0x03 (at register 0xff).
  14 *
  15 * Also supports the LM82 temp sensor, which is basically a stripped down
  16 * model of the LM83.  Datasheet is here:
  17 * http://www.national.com/pf/LM/LM82.html
  18 *
  19 * This program is free software; you can redistribute it and/or modify
  20 * it under the terms of the GNU General Public License as published by
  21 * the Free Software Foundation; either version 2 of the License, or
  22 * (at your option) any later version.
  23 *
  24 * This program is distributed in the hope that it will be useful,
  25 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27 * GNU General Public License for more details.
  28 *
  29 * You should have received a copy of the GNU General Public License
  30 * along with this program; if not, write to the Free Software
  31 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  32 */
  33
  34#include <linux/module.h>
  35#include <linux/init.h>
  36#include <linux/slab.h>
  37#include <linux/jiffies.h>
  38#include <linux/i2c.h>
  39#include <linux/hwmon-sysfs.h>
  40#include <linux/hwmon.h>
  41#include <linux/err.h>
  42#include <linux/mutex.h>
  43#include <linux/sysfs.h>
  44
  45/*
  46 * Addresses to scan
  47 * Address is selected using 2 three-level pins, resulting in 9 possible
  48 * addresses.
  49 */
  50
  51static const unsigned short normal_i2c[] = {
  52        0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
  53
  54enum chips { lm83, lm82 };
  55
  56/*
  57 * The LM83 registers
  58 * Manufacturer ID is 0x01 for National Semiconductor.
  59 */
  60
  61#define LM83_REG_R_MAN_ID               0xFE
  62#define LM83_REG_R_CHIP_ID              0xFF
  63#define LM83_REG_R_CONFIG               0x03
  64#define LM83_REG_W_CONFIG               0x09
  65#define LM83_REG_R_STATUS1              0x02
  66#define LM83_REG_R_STATUS2              0x35
  67#define LM83_REG_R_LOCAL_TEMP           0x00
  68#define LM83_REG_R_LOCAL_HIGH           0x05
  69#define LM83_REG_W_LOCAL_HIGH           0x0B
  70#define LM83_REG_R_REMOTE1_TEMP         0x30
  71#define LM83_REG_R_REMOTE1_HIGH         0x38
  72#define LM83_REG_W_REMOTE1_HIGH         0x50
  73#define LM83_REG_R_REMOTE2_TEMP         0x01
  74#define LM83_REG_R_REMOTE2_HIGH         0x07
  75#define LM83_REG_W_REMOTE2_HIGH         0x0D
  76#define LM83_REG_R_REMOTE3_TEMP         0x31
  77#define LM83_REG_R_REMOTE3_HIGH         0x3A
  78#define LM83_REG_W_REMOTE3_HIGH         0x52
  79#define LM83_REG_R_TCRIT                0x42
  80#define LM83_REG_W_TCRIT                0x5A
  81
  82/*
  83 * Conversions and various macros
  84 * The LM83 uses signed 8-bit values with LSB = 1 degree Celsius.
  85 */
  86
  87#define TEMP_FROM_REG(val)      ((val) * 1000)
  88#define TEMP_TO_REG(val)        ((val) <= -128000 ? -128 : \
  89                                 (val) >= 127000 ? 127 : \
  90                                 (val) < 0 ? ((val) - 500) / 1000 : \
  91                                 ((val) + 500) / 1000)
  92
  93static const u8 LM83_REG_R_TEMP[] = {
  94        LM83_REG_R_LOCAL_TEMP,
  95        LM83_REG_R_REMOTE1_TEMP,
  96        LM83_REG_R_REMOTE2_TEMP,
  97        LM83_REG_R_REMOTE3_TEMP,
  98        LM83_REG_R_LOCAL_HIGH,
  99        LM83_REG_R_REMOTE1_HIGH,
 100        LM83_REG_R_REMOTE2_HIGH,
 101        LM83_REG_R_REMOTE3_HIGH,
 102        LM83_REG_R_TCRIT,
 103};
 104
 105static const u8 LM83_REG_W_HIGH[] = {
 106        LM83_REG_W_LOCAL_HIGH,
 107        LM83_REG_W_REMOTE1_HIGH,
 108        LM83_REG_W_REMOTE2_HIGH,
 109        LM83_REG_W_REMOTE3_HIGH,
 110        LM83_REG_W_TCRIT,
 111};
 112
 113/*
 114 * Functions declaration
 115 */
 116
 117static int lm83_detect(struct i2c_client *new_client,
 118                       struct i2c_board_info *info);
 119static int lm83_probe(struct i2c_client *client,
 120                      const struct i2c_device_id *id);
 121static int lm83_remove(struct i2c_client *client);
 122static struct lm83_data *lm83_update_device(struct device *dev);
 123
 124/*
 125 * Driver data (common to all clients)
 126 */
 127
 128static const struct i2c_device_id lm83_id[] = {
 129        { "lm83", lm83 },
 130        { "lm82", lm82 },
 131        { }
 132};
 133MODULE_DEVICE_TABLE(i2c, lm83_id);
 134
 135static struct i2c_driver lm83_driver = {
 136        .class          = I2C_CLASS_HWMON,
 137        .driver = {
 138                .name   = "lm83",
 139        },
 140        .probe          = lm83_probe,
 141        .remove         = lm83_remove,
 142        .id_table       = lm83_id,
 143        .detect         = lm83_detect,
 144        .address_list   = normal_i2c,
 145};
 146
 147/*
 148 * Client data (each client gets its own)
 149 */
 150
 151struct lm83_data {
 152        struct device *hwmon_dev;
 153        struct mutex update_lock;
 154        char valid; /* zero until following fields are valid */
 155        unsigned long last_updated; /* in jiffies */
 156
 157        /* registers values */
 158        s8 temp[9];     /* 0..3: input 1-4,
 159                           4..7: high limit 1-4,
 160                           8   : critical limit */
 161        u16 alarms; /* bitvector, combined */
 162};
 163
 164/*
 165 * Sysfs stuff
 166 */
 167
 168static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
 169                         char *buf)
 170{
 171        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 172        struct lm83_data *data = lm83_update_device(dev);
 173        return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]));
 174}
 175
 176static ssize_t set_temp(struct device *dev, struct device_attribute *devattr,
 177                        const char *buf, size_t count)
 178{
 179        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 180        struct i2c_client *client = to_i2c_client(dev);
 181        struct lm83_data *data = i2c_get_clientdata(client);
 182        long val;
 183        int nr = attr->index;
 184        int err;
 185
 186        err = kstrtol(buf, 10, &val);
 187        if (err < 0)
 188                return err;
 189
 190        mutex_lock(&data->update_lock);
 191        data->temp[nr] = TEMP_TO_REG(val);
 192        i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr - 4],
 193                                  data->temp[nr]);
 194        mutex_unlock(&data->update_lock);
 195        return count;
 196}
 197
 198static ssize_t show_alarms(struct device *dev, struct device_attribute *dummy,
 199                           char *buf)
 200{
 201        struct lm83_data *data = lm83_update_device(dev);
 202        return sprintf(buf, "%d\n", data->alarms);
 203}
 204
 205static ssize_t show_alarm(struct device *dev, struct device_attribute
 206                          *devattr, char *buf)
 207{
 208        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 209        struct lm83_data *data = lm83_update_device(dev);
 210        int bitnr = attr->index;
 211
 212        return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
 213}
 214
 215static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
 216static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
 217static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
 218static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
 219static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp,
 220        set_temp, 4);
 221static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp,
 222        set_temp, 5);
 223static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_temp,
 224        set_temp, 6);
 225static SENSOR_DEVICE_ATTR(temp4_max, S_IWUSR | S_IRUGO, show_temp,
 226        set_temp, 7);
 227static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, 8);
 228static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO, show_temp, NULL, 8);
 229static SENSOR_DEVICE_ATTR(temp3_crit, S_IWUSR | S_IRUGO, show_temp,
 230        set_temp, 8);
 231static SENSOR_DEVICE_ATTR(temp4_crit, S_IRUGO, show_temp, NULL, 8);
 232
 233/* Individual alarm files */
 234static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 0);
 235static SENSOR_DEVICE_ATTR(temp3_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
 236static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_alarm, NULL, 2);
 237static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_alarm, NULL, 4);
 238static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 6);
 239static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 8);
 240static SENSOR_DEVICE_ATTR(temp4_crit_alarm, S_IRUGO, show_alarm, NULL, 9);
 241static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_alarm, NULL, 10);
 242static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_alarm, NULL, 12);
 243static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 13);
 244static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 15);
 245/* Raw alarm file for compatibility */
 246static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
 247
 248static struct attribute *lm83_attributes[] = {
 249        &sensor_dev_attr_temp1_input.dev_attr.attr,
 250        &sensor_dev_attr_temp3_input.dev_attr.attr,
 251        &sensor_dev_attr_temp1_max.dev_attr.attr,
 252        &sensor_dev_attr_temp3_max.dev_attr.attr,
 253        &sensor_dev_attr_temp1_crit.dev_attr.attr,
 254        &sensor_dev_attr_temp3_crit.dev_attr.attr,
 255
 256        &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
 257        &sensor_dev_attr_temp3_crit_alarm.dev_attr.attr,
 258        &sensor_dev_attr_temp3_fault.dev_attr.attr,
 259        &sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
 260        &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 261        &dev_attr_alarms.attr,
 262        NULL
 263};
 264
 265static const struct attribute_group lm83_group = {
 266        .attrs = lm83_attributes,
 267};
 268
 269static struct attribute *lm83_attributes_opt[] = {
 270        &sensor_dev_attr_temp2_input.dev_attr.attr,
 271        &sensor_dev_attr_temp4_input.dev_attr.attr,
 272        &sensor_dev_attr_temp2_max.dev_attr.attr,
 273        &sensor_dev_attr_temp4_max.dev_attr.attr,
 274        &sensor_dev_attr_temp2_crit.dev_attr.attr,
 275        &sensor_dev_attr_temp4_crit.dev_attr.attr,
 276
 277        &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
 278        &sensor_dev_attr_temp4_crit_alarm.dev_attr.attr,
 279        &sensor_dev_attr_temp4_fault.dev_attr.attr,
 280        &sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
 281        &sensor_dev_attr_temp2_fault.dev_attr.attr,
 282        &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
 283        NULL
 284};
 285
 286static const struct attribute_group lm83_group_opt = {
 287        .attrs = lm83_attributes_opt,
 288};
 289
 290/*
 291 * Real code
 292 */
 293
 294/* Return 0 if detection is successful, -ENODEV otherwise */
 295static int lm83_detect(struct i2c_client *new_client,
 296                       struct i2c_board_info *info)
 297{
 298        struct i2c_adapter *adapter = new_client->adapter;
 299        const char *name;
 300        u8 man_id, chip_id;
 301
 302        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 303                return -ENODEV;
 304
 305        /* Detection */
 306        if ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1) & 0xA8) ||
 307            (i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2) & 0x48) ||
 308            (i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG) & 0x41)) {
 309                dev_dbg(&adapter->dev, "LM83 detection failed at 0x%02x\n",
 310                        new_client->addr);
 311                return -ENODEV;
 312        }
 313
 314        /* Identification */
 315        man_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_MAN_ID);
 316        if (man_id != 0x01)     /* National Semiconductor */
 317                return -ENODEV;
 318
 319        chip_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_CHIP_ID);
 320        switch (chip_id) {
 321        case 0x03:
 322                name = "lm83";
 323                break;
 324        case 0x01:
 325                name = "lm82";
 326                break;
 327        default:
 328                /* identification failed */
 329                dev_info(&adapter->dev,
 330                         "Unsupported chip (man_id=0x%02X, chip_id=0x%02X)\n",
 331                         man_id, chip_id);
 332                return -ENODEV;
 333        }
 334
 335        strlcpy(info->type, name, I2C_NAME_SIZE);
 336
 337        return 0;
 338}
 339
 340static int lm83_probe(struct i2c_client *new_client,
 341                      const struct i2c_device_id *id)
 342{
 343        struct lm83_data *data;
 344        int err;
 345
 346        data = devm_kzalloc(&new_client->dev, sizeof(struct lm83_data),
 347                            GFP_KERNEL);
 348        if (!data)
 349                return -ENOMEM;
 350
 351        i2c_set_clientdata(new_client, data);
 352        data->valid = 0;
 353        mutex_init(&data->update_lock);
 354
 355        /*
 356         * Register sysfs hooks
 357         * The LM82 can only monitor one external diode which is
 358         * at the same register as the LM83 temp3 entry - so we
 359         * declare 1 and 3 common, and then 2 and 4 only for the LM83.
 360         */
 361
 362        err = sysfs_create_group(&new_client->dev.kobj, &lm83_group);
 363        if (err)
 364                return err;
 365
 366        if (id->driver_data == lm83) {
 367                err = sysfs_create_group(&new_client->dev.kobj,
 368                                         &lm83_group_opt);
 369                if (err)
 370                        goto exit_remove_files;
 371        }
 372
 373        data->hwmon_dev = hwmon_device_register(&new_client->dev);
 374        if (IS_ERR(data->hwmon_dev)) {
 375                err = PTR_ERR(data->hwmon_dev);
 376                goto exit_remove_files;
 377        }
 378
 379        return 0;
 380
 381exit_remove_files:
 382        sysfs_remove_group(&new_client->dev.kobj, &lm83_group);
 383        sysfs_remove_group(&new_client->dev.kobj, &lm83_group_opt);
 384        return err;
 385}
 386
 387static int lm83_remove(struct i2c_client *client)
 388{
 389        struct lm83_data *data = i2c_get_clientdata(client);
 390
 391        hwmon_device_unregister(data->hwmon_dev);
 392        sysfs_remove_group(&client->dev.kobj, &lm83_group);
 393        sysfs_remove_group(&client->dev.kobj, &lm83_group_opt);
 394
 395        return 0;
 396}
 397
 398static struct lm83_data *lm83_update_device(struct device *dev)
 399{
 400        struct i2c_client *client = to_i2c_client(dev);
 401        struct lm83_data *data = i2c_get_clientdata(client);
 402
 403        mutex_lock(&data->update_lock);
 404
 405        if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
 406                int nr;
 407
 408                dev_dbg(&client->dev, "Updating lm83 data.\n");
 409                for (nr = 0; nr < 9; nr++) {
 410                        data->temp[nr] =
 411                            i2c_smbus_read_byte_data(client,
 412                            LM83_REG_R_TEMP[nr]);
 413                }
 414                data->alarms =
 415                    i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1)
 416                    + (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2)
 417                    << 8);
 418
 419                data->last_updated = jiffies;
 420                data->valid = 1;
 421        }
 422
 423        mutex_unlock(&data->update_lock);
 424
 425        return data;
 426}
 427
 428module_i2c_driver(lm83_driver);
 429
 430MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
 431MODULE_DESCRIPTION("LM83 driver");
 432MODULE_LICENSE("GPL");
 433
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