LXR linux/drivers/hwmon/lm83.c

   1/*
   2 * lm83.c - Part of lm_sensors, Linux kernel modules for hardware
   3 *          monitoring
   4 * Copyright (C) 2003-2009  Jean Delvare <jdelvare@suse.de>
   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
  30#include <linux/module.h>
  31#include <linux/init.h>
  32#include <linux/slab.h>
  33#include <linux/jiffies.h>
  34#include <linux/i2c.h>
  35#include <linux/hwmon-sysfs.h>
  36#include <linux/hwmon.h>
  37#include <linux/err.h>
  38#include <linux/mutex.h>
  39#include <linux/sysfs.h>
  40
  41/*
  42 * Addresses to scan
  43 * Address is selected using 2 three-level pins, resulting in 9 possible
  44 * addresses.
  45 */
  46
  47static const unsigned short normal_i2c[] = {
  48        0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
  49
  50enum chips { lm83, lm82 };
  51
  52/*
  53 * The LM83 registers
  54 * Manufacturer ID is 0x01 for National Semiconductor.
  55 */
  56
  57#define LM83_REG_R_MAN_ID               0xFE
  58#define LM83_REG_R_CHIP_ID              0xFF
  59#define LM83_REG_R_CONFIG               0x03
  60#define LM83_REG_W_CONFIG               0x09
  61#define LM83_REG_R_STATUS1              0x02
  62#define LM83_REG_R_STATUS2              0x35
  63#define LM83_REG_R_LOCAL_TEMP           0x00
  64#define LM83_REG_R_LOCAL_HIGH           0x05
  65#define LM83_REG_W_LOCAL_HIGH           0x0B
  66#define LM83_REG_R_REMOTE1_TEMP         0x30
  67#define LM83_REG_R_REMOTE1_HIGH         0x38
  68#define LM83_REG_W_REMOTE1_HIGH         0x50
  69#define LM83_REG_R_REMOTE2_TEMP         0x01
  70#define LM83_REG_R_REMOTE2_HIGH         0x07
  71#define LM83_REG_W_REMOTE2_HIGH         0x0D
  72#define LM83_REG_R_REMOTE3_TEMP         0x31
  73#define LM83_REG_R_REMOTE3_HIGH         0x3A
  74#define LM83_REG_W_REMOTE3_HIGH         0x52
  75#define LM83_REG_R_TCRIT                0x42
  76#define LM83_REG_W_TCRIT                0x5A
  77
  78/*
  79 * Conversions and various macros
  80 * The LM83 uses signed 8-bit values with LSB = 1 degree Celsius.
  81 */
  82
  83#define TEMP_FROM_REG(val)      ((val) * 1000)
  84#define TEMP_TO_REG(val)        ((val) <= -128000 ? -128 : \
  85                                 (val) >= 127000 ? 127 : \
  86                                 (val) < 0 ? ((val) - 500) / 1000 : \
  87                                 ((val) + 500) / 1000)
  88
  89static const u8 LM83_REG_R_TEMP[] = {
  90        LM83_REG_R_LOCAL_TEMP,
  91        LM83_REG_R_REMOTE1_TEMP,
  92        LM83_REG_R_REMOTE2_TEMP,
  93        LM83_REG_R_REMOTE3_TEMP,
  94        LM83_REG_R_LOCAL_HIGH,
  95        LM83_REG_R_REMOTE1_HIGH,
  96        LM83_REG_R_REMOTE2_HIGH,
  97        LM83_REG_R_REMOTE3_HIGH,
  98        LM83_REG_R_TCRIT,
  99};
 100
 101static const u8 LM83_REG_W_HIGH[] = {
 102        LM83_REG_W_LOCAL_HIGH,
 103        LM83_REG_W_REMOTE1_HIGH,
 104        LM83_REG_W_REMOTE2_HIGH,
 105        LM83_REG_W_REMOTE3_HIGH,
 106        LM83_REG_W_TCRIT,
 107};
 108
 109/*
 110 * Client data (each client gets its own)
 111 */
 112
 113struct lm83_data {
 114        struct i2c_client *client;
 115        const struct attribute_group *groups[3];
 116        struct mutex update_lock;
 117        char valid; /* zero until following fields are valid */
 118        unsigned long last_updated; /* in jiffies */
 119
 120        /* registers values */
 121        s8 temp[9];     /* 0..3: input 1-4,
 122                           4..7: high limit 1-4,
 123                           8   : critical limit */
 124        u16 alarms; /* bitvector, combined */
 125};
 126
 127static struct lm83_data *lm83_update_device(struct device *dev)
 128{
 129        struct lm83_data *data = dev_get_drvdata(dev);
 130        struct i2c_client *client = data->client;
 131
 132        mutex_lock(&data->update_lock);
 133
 134        if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
 135                int nr;
 136
 137                dev_dbg(&client->dev, "Updating lm83 data.\n");
 138                for (nr = 0; nr < 9; nr++) {
 139                        data->temp[nr] =
 140                            i2c_smbus_read_byte_data(client,
 141                            LM83_REG_R_TEMP[nr]);
 142                }
 143                data->alarms =
 144                    i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1)
 145                    + (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2)
 146                    << 8);
 147
 148                data->last_updated = jiffies;
 149                data->valid = 1;
 150        }
 151
 152        mutex_unlock(&data->update_lock);
 153
 154        return data;
 155}
 156
 157/*
 158 * Sysfs stuff
 159 */
 160
 161static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
 162                         char *buf)
 163{
 164        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 165        struct lm83_data *data = lm83_update_device(dev);
 166        return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]));
 167}
 168
 169static ssize_t set_temp(struct device *dev, struct device_attribute *devattr,
 170                        const char *buf, size_t count)
 171{
 172        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 173        struct lm83_data *data = dev_get_drvdata(dev);
 174        struct i2c_client *client = data->client;
 175        long val;
 176        int nr = attr->index;
 177        int err;
 178
 179        err = kstrtol(buf, 10, &val);
 180        if (err < 0)
 181                return err;
 182
 183        mutex_lock(&data->update_lock);
 184        data->temp[nr] = TEMP_TO_REG(val);
 185        i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr - 4],
 186                                  data->temp[nr]);
 187        mutex_unlock(&data->update_lock);
 188        return count;
 189}
 190
 191static ssize_t alarms_show(struct device *dev, struct device_attribute *dummy,
 192                           char *buf)
 193{
 194        struct lm83_data *data = lm83_update_device(dev);
 195        return sprintf(buf, "%d\n", data->alarms);
 196}
 197
 198static ssize_t show_alarm(struct device *dev, struct device_attribute
 199                          *devattr, char *buf)
 200{
 201        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 202        struct lm83_data *data = lm83_update_device(dev);
 203        int bitnr = attr->index;
 204
 205        return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
 206}
 207
 208static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
 209static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
 210static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
 211static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
 212static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp,
 213        set_temp, 4);
 214static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp,
 215        set_temp, 5);
 216static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_temp,
 217        set_temp, 6);
 218static SENSOR_DEVICE_ATTR(temp4_max, S_IWUSR | S_IRUGO, show_temp,
 219        set_temp, 7);
 220static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, 8);
 221static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO, show_temp, NULL, 8);
 222static SENSOR_DEVICE_ATTR(temp3_crit, S_IWUSR | S_IRUGO, show_temp,
 223        set_temp, 8);
 224static SENSOR_DEVICE_ATTR(temp4_crit, S_IRUGO, show_temp, NULL, 8);
 225
 226/* Individual alarm files */
 227static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 0);
 228static SENSOR_DEVICE_ATTR(temp3_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
 229static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_alarm, NULL, 2);
 230static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_alarm, NULL, 4);
 231static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 6);
 232static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 8);
 233static SENSOR_DEVICE_ATTR(temp4_crit_alarm, S_IRUGO, show_alarm, NULL, 9);
 234static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_alarm, NULL, 10);
 235static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_alarm, NULL, 12);
 236static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 13);
 237static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 15);
 238/* Raw alarm file for compatibility */
 239static DEVICE_ATTR_RO(alarms);
 240
 241static struct attribute *lm83_attributes[] = {
 242        &sensor_dev_attr_temp1_input.dev_attr.attr,
 243        &sensor_dev_attr_temp3_input.dev_attr.attr,
 244        &sensor_dev_attr_temp1_max.dev_attr.attr,
 245        &sensor_dev_attr_temp3_max.dev_attr.attr,
 246        &sensor_dev_attr_temp1_crit.dev_attr.attr,
 247        &sensor_dev_attr_temp3_crit.dev_attr.attr,
 248
 249        &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
 250        &sensor_dev_attr_temp3_crit_alarm.dev_attr.attr,
 251        &sensor_dev_attr_temp3_fault.dev_attr.attr,
 252        &sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
 253        &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 254        &dev_attr_alarms.attr,
 255        NULL
 256};
 257
 258static const struct attribute_group lm83_group = {
 259        .attrs = lm83_attributes,
 260};
 261
 262static struct attribute *lm83_attributes_opt[] = {
 263        &sensor_dev_attr_temp2_input.dev_attr.attr,
 264        &sensor_dev_attr_temp4_input.dev_attr.attr,
 265        &sensor_dev_attr_temp2_max.dev_attr.attr,
 266        &sensor_dev_attr_temp4_max.dev_attr.attr,
 267        &sensor_dev_attr_temp2_crit.dev_attr.attr,
 268        &sensor_dev_attr_temp4_crit.dev_attr.attr,
 269
 270        &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
 271        &sensor_dev_attr_temp4_crit_alarm.dev_attr.attr,
 272        &sensor_dev_attr_temp4_fault.dev_attr.attr,
 273        &sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
 274        &sensor_dev_attr_temp2_fault.dev_attr.attr,
 275        &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
 276        NULL
 277};
 278
 279static const struct attribute_group lm83_group_opt = {
 280        .attrs = lm83_attributes_opt,
 281};
 282
 283/*
 284 * Real code
 285 */
 286
 287/* Return 0 if detection is successful, -ENODEV otherwise */
 288static int lm83_detect(struct i2c_client *new_client,
 289                       struct i2c_board_info *info)
 290{
 291        struct i2c_adapter *adapter = new_client->adapter;
 292        const char *name;
 293        u8 man_id, chip_id;
 294
 295        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 296                return -ENODEV;
 297
 298        /* Detection */
 299        if ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1) & 0xA8) ||
 300            (i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2) & 0x48) ||
 301            (i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG) & 0x41)) {
 302                dev_dbg(&adapter->dev, "LM83 detection failed at 0x%02x\n",
 303                        new_client->addr);
 304                return -ENODEV;
 305        }
 306
 307        /* Identification */
 308        man_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_MAN_ID);
 309        if (man_id != 0x01)     /* National Semiconductor */
 310                return -ENODEV;
 311
 312        chip_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_CHIP_ID);
 313        switch (chip_id) {
 314        case 0x03:
 315                name = "lm83";
 316                break;
 317        case 0x01:
 318                name = "lm82";
 319                break;
 320        default:
 321                /* identification failed */
 322                dev_info(&adapter->dev,
 323                         "Unsupported chip (man_id=0x%02X, chip_id=0x%02X)\n",
 324                         man_id, chip_id);
 325                return -ENODEV;
 326        }
 327
 328        strlcpy(info->type, name, I2C_NAME_SIZE);
 329
 330        return 0;
 331}
 332
 333static int lm83_probe(struct i2c_client *new_client,
 334                      const struct i2c_device_id *id)
 335{
 336        struct device *hwmon_dev;
 337        struct lm83_data *data;
 338
 339        data = devm_kzalloc(&new_client->dev, sizeof(struct lm83_data),
 340                            GFP_KERNEL);
 341        if (!data)
 342                return -ENOMEM;
 343
 344        data->client = new_client;
 345        mutex_init(&data->update_lock);
 346
 347        /*
 348         * Register sysfs hooks
 349         * The LM82 can only monitor one external diode which is
 350         * at the same register as the LM83 temp3 entry - so we
 351         * declare 1 and 3 common, and then 2 and 4 only for the LM83.
 352         */
 353        data->groups[0] = &lm83_group;
 354        if (id->driver_data == lm83)
 355                data->groups[1] = &lm83_group_opt;
 356
 357        hwmon_dev = devm_hwmon_device_register_with_groups(&new_client->dev,
 358                                                           new_client->name,
 359                                                           data, data->groups);
 360        return PTR_ERR_OR_ZERO(hwmon_dev);
 361}
 362
 363/*
 364 * Driver data (common to all clients)
 365 */
 366
 367static const struct i2c_device_id lm83_id[] = {
 368        { "lm83", lm83 },
 369        { "lm82", lm82 },
 370        { }
 371};
 372MODULE_DEVICE_TABLE(i2c, lm83_id);
 373
 374static struct i2c_driver lm83_driver = {
 375        .class          = I2C_CLASS_HWMON,
 376        .driver = {
 377                .name   = "lm83",
 378        },
 379        .probe          = lm83_probe,
 380        .id_table       = lm83_id,
 381        .detect         = lm83_detect,
 382        .address_list   = normal_i2c,
 383};
 384
 385module_i2c_driver(lm83_driver);
 386
 387MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
 388MODULE_DESCRIPTION("LM83 driver");
 389MODULE_LICENSE("GPL");
 390