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
  51 static 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
  58 I2C_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
  97 static 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
 109 static 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
 121 static int lm83_detect(struct i2c_client *new_client, int kind,
 122                        struct i2c_board_info *info);
 123 static int lm83_probe(struct i2c_client *client,
 124                       const struct i2c_device_id *id);
 125 static int lm83_remove(struct i2c_client *client);
 126 static struct lm83_data *lm83_update_device(struct device *dev);
 127
 128 /*
 129  * Driver data (common to all clients)
 130  */
 131
 132 static const struct i2c_device_id lm83_id[] = {
 133         { "lm83", lm83 },
 134         { "lm82", lm82 },
 135         { }
 136 };
 137 MODULE_DEVICE_TABLE(i2c, lm83_id);
 138
 139 static 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
 155 struct 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
 172 static 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
 180 static 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
 197 static 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
 204 static 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
 214 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
 215 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
 216 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
 217 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
 218 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp,
 219         set_temp, 4);
 220 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp,
 221         set_temp, 5);
 222 static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_temp,
 223         set_temp, 6);
 224 static SENSOR_DEVICE_ATTR(temp4_max, S_IWUSR | S_IRUGO, show_temp,
 225         set_temp, 7);
 226 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, 8);
 227 static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO, show_temp, NULL, 8);
 228 static SENSOR_DEVICE_ATTR(temp3_crit, S_IWUSR | S_IRUGO, show_temp,
 229         set_temp, 8);
 230 static SENSOR_DEVICE_ATTR(temp4_crit, S_IRUGO, show_temp, NULL, 8);
 231
 232 /* Individual alarm files */
 233 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 0);
 234 static SENSOR_DEVICE_ATTR(temp3_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
 235 static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_alarm, NULL, 2);
 236 static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_alarm, NULL, 4);
 237 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 6);
 238 static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 8);
 239 static SENSOR_DEVICE_ATTR(temp4_crit_alarm, S_IRUGO, show_alarm, NULL, 9);
 240 static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_alarm, NULL, 10);
 241 static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_alarm, NULL, 12);
 242 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 13);
 243 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 15);
 244 /* Raw alarm file for compatibility */
 245 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
 246
 247 static 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
 264 static const struct attribute_group lm83_group = {
 265         .attrs = lm83_attributes,
 266 };
 267
 268 static 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
 285 static 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 */
 294 static 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
 368 static 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
 408 exit_remove_files:
 409         sysfs_remove_group(&new_client->dev.kobj, &lm83_group);
 410         sysfs_remove_group(&new_client->dev.kobj, &lm83_group_opt);
 411 exit_free:
 412         kfree(data);
 413 exit:
 414         return err;
 415 }
 416
 417 static 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
 429 static 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
 459 static int __init sensors_lm83_init(void)
 460 {
 461         return i2c_add_driver(&lm83_driver);
 462 }
 463
 464 static void __exit sensors_lm83_exit(void)
 465 {
 466         i2c_del_driver(&lm83_driver);
 467 }
 468
 469 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
 470 MODULE_DESCRIPTION("LM83 driver");
 471 MODULE_LICENSE("GPL");
 472
 473 module_init(sensors_lm83_init);
 474 module_exit(sensors_lm83_exit);