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 <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 enum 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
  93 static 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
 105 static 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
 117 static int lm83_detect(struct i2c_client *new_client,
 118                        struct i2c_board_info *info);
 119 static int lm83_probe(struct i2c_client *client,
 120                       const struct i2c_device_id *id);
 121 static int lm83_remove(struct i2c_client *client);
 122 static struct lm83_data *lm83_update_device(struct device *dev);
 123
 124 /*
 125  * Driver data (common to all clients)
 126  */
 127
 128 static const struct i2c_device_id lm83_id[] = {
 129         { "lm83", lm83 },
 130         { "lm82", lm82 },
 131         { }
 132 };
 133 MODULE_DEVICE_TABLE(i2c, lm83_id);
 134
 135 static 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
 151 struct 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
 168 static 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
 176 static 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
 198 static 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
 205 static 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
 215 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
 216 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
 217 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
 218 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
 219 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp,
 220         set_temp, 4);
 221 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp,
 222         set_temp, 5);
 223 static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_temp,
 224         set_temp, 6);
 225 static SENSOR_DEVICE_ATTR(temp4_max, S_IWUSR | S_IRUGO, show_temp,
 226         set_temp, 7);
 227 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, 8);
 228 static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO, show_temp, NULL, 8);
 229 static SENSOR_DEVICE_ATTR(temp3_crit, S_IWUSR | S_IRUGO, show_temp,
 230         set_temp, 8);
 231 static SENSOR_DEVICE_ATTR(temp4_crit, S_IRUGO, show_temp, NULL, 8);
 232
 233 /* Individual alarm files */
 234 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 0);
 235 static SENSOR_DEVICE_ATTR(temp3_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
 236 static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_alarm, NULL, 2);
 237 static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_alarm, NULL, 4);
 238 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 6);
 239 static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 8);
 240 static SENSOR_DEVICE_ATTR(temp4_crit_alarm, S_IRUGO, show_alarm, NULL, 9);
 241 static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_alarm, NULL, 10);
 242 static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_alarm, NULL, 12);
 243 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 13);
 244 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 15);
 245 /* Raw alarm file for compatibility */
 246 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
 247
 248 static 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
 265 static const struct attribute_group lm83_group = {
 266         .attrs = lm83_attributes,
 267 };
 268
 269 static 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
 286 static 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 */
 295 static 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
 340 static 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
 381 exit_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
 387 static 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
 398 static 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
 428 module_i2c_driver(lm83_driver);
 429
 430 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
 431 MODULE_DESCRIPTION("LM83 driver");
 432 MODULE_LICENSE("GPL");