LXR linux/drivers/hwmon/lm83.c

   1/*
   2 * lm83.c - Part of lm_sensors, Linux kernel modules for hardware
   3 *          monitoring
   4 * Copyright (C) 2003-2008  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
  54/*
  55 * Insmod parameters
  56 */
  57
  58I2C_CLIENT_INSMOD_2(lm83, lm82);
  59
  60/*
  61 * The LM83 registers
  62 * Manufacturer ID is 0x01 for National Semiconductor.
  63 */
  64
  65#define LM83_REG_R_MAN_ID               0xFE
  66#define LM83_REG_R_CHIP_ID              0xFF
  67#define LM83_REG_R_CONFIG               0x03
  68#define LM83_REG_W_CONFIG               0x09
  69#define LM83_REG_R_STATUS1              0x02
  70#define LM83_REG_R_STATUS2              0x35
  71#define LM83_REG_R_LOCAL_TEMP           0x00
  72#define LM83_REG_R_LOCAL_HIGH           0x05
  73#define LM83_REG_W_LOCAL_HIGH           0x0B
  74#define LM83_REG_R_REMOTE1_TEMP         0x30
  75#define LM83_REG_R_REMOTE1_HIGH         0x38
  76#define LM83_REG_W_REMOTE1_HIGH         0x50
  77#define LM83_REG_R_REMOTE2_TEMP         0x01
  78#define LM83_REG_R_REMOTE2_HIGH         0x07
  79#define LM83_REG_W_REMOTE2_HIGH         0x0D
  80#define LM83_REG_R_REMOTE3_TEMP         0x31
  81#define LM83_REG_R_REMOTE3_HIGH         0x3A
  82#define LM83_REG_W_REMOTE3_HIGH         0x52
  83#define LM83_REG_R_TCRIT                0x42
  84#define LM83_REG_W_TCRIT                0x5A
  85
  86/*
  87 * Conversions and various macros
  88 * The LM83 uses signed 8-bit values with LSB = 1 degree Celsius.
  89 */
  90
  91#define TEMP_FROM_REG(val)      ((val) * 1000)
  92#define TEMP_TO_REG(val)        ((val) <= -128000 ? -128 : \
  93                                 (val) >= 127000 ? 127 : \
  94                                 (val) < 0 ? ((val) - 500) / 1000 : \
  95                                 ((val) + 500) / 1000)
  96
  97static const u8 LM83_REG_R_TEMP[] = {
  98        LM83_REG_R_LOCAL_TEMP,
  99        LM83_REG_R_REMOTE1_TEMP,
 100        LM83_REG_R_REMOTE2_TEMP,
 101        LM83_REG_R_REMOTE3_TEMP,
 102        LM83_REG_R_LOCAL_HIGH,
 103        LM83_REG_R_REMOTE1_HIGH,
 104        LM83_REG_R_REMOTE2_HIGH,
 105        LM83_REG_R_REMOTE3_HIGH,
 106        LM83_REG_R_TCRIT,
 107};
 108
 109static const u8 LM83_REG_W_HIGH[] = {
 110        LM83_REG_W_LOCAL_HIGH,
 111        LM83_REG_W_REMOTE1_HIGH,
 112        LM83_REG_W_REMOTE2_HIGH,
 113        LM83_REG_W_REMOTE3_HIGH,
 114        LM83_REG_W_TCRIT,
 115};
 116
 117/*
 118 * Functions declaration
 119 */
 120
 121static int lm83_detect(struct i2c_client *new_client, int kind,
 122                       struct i2c_board_info *info);
 123static int lm83_probe(struct i2c_client *client,
 124                      const struct i2c_device_id *id);
 125static int lm83_remove(struct i2c_client *client);
 126static struct lm83_data *lm83_update_device(struct device *dev);
 127
 128/*
 129 * Driver data (common to all clients)
 130 */
 131 
 132static const struct i2c_device_id lm83_id[] = {
 133        { "lm83", lm83 },
 134        { "lm82", lm82 },
 135        { }
 136};
 137MODULE_DEVICE_TABLE(i2c, lm83_id);
 138
 139static struct i2c_driver lm83_driver = {
 140        .class          = I2C_CLASS_HWMON,
 141        .driver = {
 142                .name   = "lm83",
 143        },
 144        .probe          = lm83_probe,
 145        .remove         = lm83_remove,
 146        .id_table       = lm83_id,
 147        .detect         = lm83_detect,
 148        .address_data   = &addr_data,
 149};
 150
 151/*
 152 * Client data (each client gets its own)
 153 */
 154
 155struct lm83_data {
 156        struct device *hwmon_dev;
 157        struct mutex update_lock;
 158        char valid; /* zero until following fields are valid */
 159        unsigned long last_updated; /* in jiffies */
 160
 161        /* registers values */
 162        s8 temp[9];     /* 0..3: input 1-4,
 163                           4..7: high limit 1-4,
 164                           8   : critical limit */
 165        u16 alarms; /* bitvector, combined */
 166};
 167
 168/*
 169 * Sysfs stuff
 170 */
 171
 172static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
 173                         char *buf)
 174{
 175        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 176        struct lm83_data *data = lm83_update_device(dev);
 177        return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]));
 178}
 179
 180static ssize_t set_temp(struct device *dev, struct device_attribute *devattr,
 181                        const char *buf, size_t count)
 182{
 183        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 184        struct i2c_client *client = to_i2c_client(dev);
 185        struct lm83_data *data = i2c_get_clientdata(client);
 186        long val = simple_strtol(buf, NULL, 10);
 187        int nr = attr->index;
 188
 189        mutex_lock(&data->update_lock);
 190        data->temp[nr] = TEMP_TO_REG(val);
 191        i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr - 4],
 192                                  data->temp[nr]);
 193        mutex_unlock(&data->update_lock);
 194        return count;
 195}
 196
 197static ssize_t show_alarms(struct device *dev, struct device_attribute *dummy,
 198                           char *buf)
 199{
 200        struct lm83_data *data = lm83_update_device(dev);
 201        return sprintf(buf, "%d\n", data->alarms);
 202}
 203
 204static ssize_t show_alarm(struct device *dev, struct device_attribute
 205                          *devattr, char *buf)
 206{
 207        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 208        struct lm83_data *data = lm83_update_device(dev);
 209        int bitnr = attr->index;
 210
 211        return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
 212}
 213
 214static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
 215static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
 216static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
 217static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
 218static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp,
 219        set_temp, 4);
 220static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp,
 221        set_temp, 5);
 222static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_temp,
 223        set_temp, 6);
 224static SENSOR_DEVICE_ATTR(temp4_max, S_IWUSR | S_IRUGO, show_temp,
 225        set_temp, 7);
 226static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, 8);
 227static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO, show_temp, NULL, 8);
 228static SENSOR_DEVICE_ATTR(temp3_crit, S_IWUSR | S_IRUGO, show_temp,
 229        set_temp, 8);
 230static SENSOR_DEVICE_ATTR(temp4_crit, S_IRUGO, show_temp, NULL, 8);
 231
 232/* Individual alarm files */
 233static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 0);
 234static SENSOR_DEVICE_ATTR(temp3_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
 235static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_alarm, NULL, 2);
 236static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_alarm, NULL, 4);
 237static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 6);
 238static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 8);
 239static SENSOR_DEVICE_ATTR(temp4_crit_alarm, S_IRUGO, show_alarm, NULL, 9);
 240static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_alarm, NULL, 10);
 241static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_alarm, NULL, 12);
 242static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 13);
 243static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 15);
 244/* Raw alarm file for compatibility */
 245static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
 246
 247static struct attribute *lm83_attributes[] = {
 248        &sensor_dev_attr_temp1_input.dev_attr.attr,
 249        &sensor_dev_attr_temp3_input.dev_attr.attr,
 250        &sensor_dev_attr_temp1_max.dev_attr.attr,
 251        &sensor_dev_attr_temp3_max.dev_attr.attr,
 252        &sensor_dev_attr_temp1_crit.dev_attr.attr,
 253        &sensor_dev_attr_temp3_crit.dev_attr.attr,
 254
 255        &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
 256        &sensor_dev_attr_temp3_crit_alarm.dev_attr.attr,
 257        &sensor_dev_attr_temp3_fault.dev_attr.attr,
 258        &sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
 259        &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 260        &dev_attr_alarms.attr,
 261        NULL
 262};
 263
 264static const struct attribute_group lm83_group = {
 265        .attrs = lm83_attributes,
 266};
 267
 268static struct attribute *lm83_attributes_opt[] = {
 269        &sensor_dev_attr_temp2_input.dev_attr.attr,
 270        &sensor_dev_attr_temp4_input.dev_attr.attr,
 271        &sensor_dev_attr_temp2_max.dev_attr.attr,
 272        &sensor_dev_attr_temp4_max.dev_attr.attr,
 273        &sensor_dev_attr_temp2_crit.dev_attr.attr,
 274        &sensor_dev_attr_temp4_crit.dev_attr.attr,
 275
 276        &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
 277        &sensor_dev_attr_temp4_crit_alarm.dev_attr.attr,
 278        &sensor_dev_attr_temp4_fault.dev_attr.attr,
 279        &sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
 280        &sensor_dev_attr_temp2_fault.dev_attr.attr,
 281        &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
 282        NULL
 283};
 284
 285static const struct attribute_group lm83_group_opt = {
 286        .attrs = lm83_attributes_opt,
 287};
 288
 289/*
 290 * Real code
 291 */
 292
 293/* Return 0 if detection is successful, -ENODEV otherwise */
 294static int lm83_detect(struct i2c_client *new_client, int kind,
 295                       struct i2c_board_info *info)
 296{
 297        struct i2c_adapter *adapter = new_client->adapter;
 298        const char *name = "";
 299
 300        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 301                return -ENODEV;
 302
 303        /* Now we do the detection and identification. A negative kind
 304         * means that the driver was loaded with no force parameter
 305         * (default), so we must both detect and identify the chip
 306         * (actually there is only one possible kind of chip for now, LM83).
 307         * A zero kind means that the driver was loaded with the force
 308         * parameter, the detection step shall be skipped. A positive kind
 309         * means that the driver was loaded with the force parameter and a
 310         * given kind of chip is requested, so both the detection and the
 311         * identification steps are skipped. */
 312
 313        /* Default to an LM83 if forced */
 314        if (kind == 0)
 315                kind = lm83;
 316
 317        if (kind < 0) { /* detection */
 318                if (((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1)
 319                    & 0xA8) != 0x00) ||
 320                    ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2)
 321                    & 0x48) != 0x00) ||
 322                    ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG)
 323                    & 0x41) != 0x00)) {
 324                        dev_dbg(&adapter->dev,
 325                                "LM83 detection failed at 0x%02x.\n",
 326                                new_client->addr);
 327                        return -ENODEV;
 328                }
 329        }
 330
 331        if (kind <= 0) { /* identification */
 332                u8 man_id, chip_id;
 333
 334                man_id = i2c_smbus_read_byte_data(new_client,
 335                    LM83_REG_R_MAN_ID);
 336                chip_id = i2c_smbus_read_byte_data(new_client,
 337                    LM83_REG_R_CHIP_ID);
 338
 339                if (man_id == 0x01) { /* National Semiconductor */
 340                        if (chip_id == 0x03) {
 341                                kind = lm83;
 342                        } else
 343                        if (chip_id == 0x01) {
 344                                kind = lm82;
 345                        }
 346                }
 347
 348                if (kind <= 0) { /* identification failed */
 349                        dev_info(&adapter->dev,
 350                            "Unsupported chip (man_id=0x%02X, "
 351                            "chip_id=0x%02X).\n", man_id, chip_id);
 352                        return -ENODEV;
 353                }
 354        }
 355
 356        if (kind == lm83) {
 357                name = "lm83";
 358        } else
 359        if (kind == lm82) {
 360                name = "lm82";
 361        }
 362
 363        strlcpy(info->type, name, I2C_NAME_SIZE);
 364
 365        return 0;
 366}
 367
 368static int lm83_probe(struct i2c_client *new_client,
 369                      const struct i2c_device_id *id)
 370{
 371        struct lm83_data *data;
 372        int err;
 373
 374        data = kzalloc(sizeof(struct lm83_data), GFP_KERNEL);
 375        if (!data) {
 376                err = -ENOMEM;
 377                goto exit;
 378        }
 379
 380        i2c_set_clientdata(new_client, data);
 381        data->valid = 0;
 382        mutex_init(&data->update_lock);
 383
 384        /*
 385         * Register sysfs hooks
 386         * The LM82 can only monitor one external diode which is
 387         * at the same register as the LM83 temp3 entry - so we
 388         * declare 1 and 3 common, and then 2 and 4 only for the LM83.
 389         */
 390
 391        if ((err = sysfs_create_group(&new_client->dev.kobj, &lm83_group)))
 392                goto exit_free;
 393
 394        if (id->driver_data == lm83) {
 395                if ((err = sysfs_create_group(&new_client->dev.kobj,
 396                                              &lm83_group_opt)))
 397                        goto exit_remove_files;
 398        }
 399
 400        data->hwmon_dev = hwmon_device_register(&new_client->dev);
 401        if (IS_ERR(data->hwmon_dev)) {
 402                err = PTR_ERR(data->hwmon_dev);
 403                goto exit_remove_files;
 404        }
 405
 406        return 0;
 407
 408exit_remove_files:
 409        sysfs_remove_group(&new_client->dev.kobj, &lm83_group);
 410        sysfs_remove_group(&new_client->dev.kobj, &lm83_group_opt);
 411exit_free:
 412        kfree(data);
 413exit:
 414        return err;
 415}
 416
 417static int lm83_remove(struct i2c_client *client)
 418{
 419        struct lm83_data *data = i2c_get_clientdata(client);
 420
 421        hwmon_device_unregister(data->hwmon_dev);
 422        sysfs_remove_group(&client->dev.kobj, &lm83_group);
 423        sysfs_remove_group(&client->dev.kobj, &lm83_group_opt);
 424
 425        kfree(data);
 426        return 0;
 427}
 428
 429static struct lm83_data *lm83_update_device(struct device *dev)
 430{
 431        struct i2c_client *client = to_i2c_client(dev);
 432        struct lm83_data *data = i2c_get_clientdata(client);
 433
 434        mutex_lock(&data->update_lock);
 435
 436        if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
 437                int nr;
 438
 439                dev_dbg(&client->dev, "Updating lm83 data.\n");
 440                for (nr = 0; nr < 9; nr++) {
 441                        data->temp[nr] =
 442                            i2c_smbus_read_byte_data(client,
 443                            LM83_REG_R_TEMP[nr]);
 444                }
 445                data->alarms =
 446                    i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1)
 447                    + (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2)
 448                    << 8);
 449
 450                data->last_updated = jiffies;
 451                data->valid = 1;
 452        }
 453
 454        mutex_unlock(&data->update_lock);
 455
 456        return data;
 457}
 458
 459static int __init sensors_lm83_init(void)
 460{
 461        return i2c_add_driver(&lm83_driver);
 462}
 463
 464static void __exit sensors_lm83_exit(void)
 465{
 466        i2c_del_driver(&lm83_driver);
 467}
 468
 469MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
 470MODULE_DESCRIPTION("LM83 driver");
 471MODULE_LICENSE("GPL");
 472
 473module_init(sensors_lm83_init);
 474module_exit(sensors_lm83_exit);
 475