drivers/hwmon/max1619.c

   1 /*
   2  * max1619.c - Part of lm_sensors, Linux kernel modules for hardware
   3  *             monitoring
   4  * Copyright (C) 2003-2004 Alexey Fisher <fishor@mail.ru>
   5  *                         Jean Delvare <khali@linux-fr.org>
   6  *
   7  * Based on the lm90 driver. The MAX1619 is a sensor chip made by Maxim.
   8  * It reports up to two temperatures (its own plus up to
   9  * one external one). Complete datasheet can be
  10  * obtained from Maxim's website at:
  11  *   http://pdfserv.maxim-ic.com/en/ds/MAX1619.pdf
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2 of the License, or
  16  * (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  26  */
  27
  28
  29 #include <linux/module.h>
  30 #include <linux/init.h>
  31 #include <linux/slab.h>
  32 #include <linux/jiffies.h>
  33 #include <linux/i2c.h>
  34 #include <linux/hwmon.h>
  35 #include <linux/hwmon-sysfs.h>
  36 #include <linux/err.h>
  37 #include <linux/mutex.h>
  38 #include <linux/sysfs.h>
  39
  40 static const unsigned short normal_i2c[] = {
  41         0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
  42
  43 /*
  44  * Insmod parameters
  45  */
  46
  47 I2C_CLIENT_INSMOD_1(max1619);
  48
  49 /*
  50  * The MAX1619 registers
  51  */
  52
  53 #define MAX1619_REG_R_MAN_ID            0xFE
  54 #define MAX1619_REG_R_CHIP_ID           0xFF
  55 #define MAX1619_REG_R_CONFIG            0x03
  56 #define MAX1619_REG_W_CONFIG            0x09
  57 #define MAX1619_REG_R_CONVRATE          0x04
  58 #define MAX1619_REG_W_CONVRATE          0x0A
  59 #define MAX1619_REG_R_STATUS            0x02
  60 #define MAX1619_REG_R_LOCAL_TEMP        0x00
  61 #define MAX1619_REG_R_REMOTE_TEMP       0x01
  62 #define MAX1619_REG_R_REMOTE_HIGH       0x07
  63 #define MAX1619_REG_W_REMOTE_HIGH       0x0D
  64 #define MAX1619_REG_R_REMOTE_LOW        0x08
  65 #define MAX1619_REG_W_REMOTE_LOW        0x0E
  66 #define MAX1619_REG_R_REMOTE_CRIT       0x10
  67 #define MAX1619_REG_W_REMOTE_CRIT       0x12
  68 #define MAX1619_REG_R_TCRIT_HYST        0x11
  69 #define MAX1619_REG_W_TCRIT_HYST        0x13
  70
  71 /*
  72  * Conversions
  73  */
  74
  75 static int temp_from_reg(int val)
  76 {
  77         return (val & 0x80 ? val-0x100 : val) * 1000;
  78 }
  79
  80 static int temp_to_reg(int val)
  81 {
  82         return (val < 0 ? val+0x100*1000 : val) / 1000;
  83 }
  84
  85 /*
  86  * Functions declaration
  87  */
  88
  89 static int max1619_probe(struct i2c_client *client,
  90                          const struct i2c_device_id *id);
  91 static int max1619_detect(struct i2c_client *client, int kind,
  92                           struct i2c_board_info *info);
  93 static void max1619_init_client(struct i2c_client *client);
  94 static int max1619_remove(struct i2c_client *client);
  95 static struct max1619_data *max1619_update_device(struct device *dev);
  96
  97 /*
  98  * Driver data (common to all clients)
  99  */
 100
 101 static const struct i2c_device_id max1619_id[] = {
 102         { "max1619", max1619 },
 103         { }
 104 };
 105 MODULE_DEVICE_TABLE(i2c, max1619_id);
 106
 107 static struct i2c_driver max1619_driver = {
 108         .class          = I2C_CLASS_HWMON,
 109         .driver = {
 110                 .name   = "max1619",
 111         },
 112         .probe          = max1619_probe,
 113         .remove         = max1619_remove,
 114         .id_table       = max1619_id,
 115         .detect         = max1619_detect,
 116         .address_data   = &addr_data,
 117 };
 118
 119 /*
 120  * Client data (each client gets its own)
 121  */
 122
 123 struct max1619_data {
 124         struct device *hwmon_dev;
 125         struct mutex update_lock;
 126         char valid; /* zero until following fields are valid */
 127         unsigned long last_updated; /* in jiffies */
 128
 129         /* registers values */
 130         u8 temp_input1; /* local */
 131         u8 temp_input2, temp_low2, temp_high2; /* remote */
 132         u8 temp_crit2;
 133         u8 temp_hyst2;
 134         u8 alarms;
 135 };
 136
 137 /*
 138  * Sysfs stuff
 139  */
 140
 141 #define show_temp(value) \
 142 static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf) \
 143 { \
 144         struct max1619_data *data = max1619_update_device(dev); \
 145         return sprintf(buf, "%d\n", temp_from_reg(data->value)); \
 146 }
 147 show_temp(temp_input1);
 148 show_temp(temp_input2);
 149 show_temp(temp_low2);
 150 show_temp(temp_high2);
 151 show_temp(temp_crit2);
 152 show_temp(temp_hyst2);
 153
 154 #define set_temp2(value, reg) \
 155 static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, \
 156         size_t count) \
 157 { \
 158         struct i2c_client *client = to_i2c_client(dev); \
 159         struct max1619_data *data = i2c_get_clientdata(client); \
 160         long val = simple_strtol(buf, NULL, 10); \
 161  \
 162         mutex_lock(&data->update_lock); \
 163         data->value = temp_to_reg(val); \
 164         i2c_smbus_write_byte_data(client, reg, data->value); \
 165         mutex_unlock(&data->update_lock); \
 166         return count; \
 167 }
 168
 169 set_temp2(temp_low2, MAX1619_REG_W_REMOTE_LOW);
 170 set_temp2(temp_high2, MAX1619_REG_W_REMOTE_HIGH);
 171 set_temp2(temp_crit2, MAX1619_REG_W_REMOTE_CRIT);
 172 set_temp2(temp_hyst2, MAX1619_REG_W_TCRIT_HYST);
 173
 174 static ssize_t show_alarms(struct device *dev, struct device_attribute *attr, char *buf)
 175 {
 176         struct max1619_data *data = max1619_update_device(dev);
 177         return sprintf(buf, "%d\n", data->alarms);
 178 }
 179
 180 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
 181                           char *buf)
 182 {
 183         int bitnr = to_sensor_dev_attr(attr)->index;
 184         struct max1619_data *data = max1619_update_device(dev);
 185         return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
 186 }
 187
 188 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
 189 static DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input2, NULL);
 190 static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_low2,
 191         set_temp_low2);
 192 static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_high2,
 193         set_temp_high2);
 194 static DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit2,
 195         set_temp_crit2);
 196 static DEVICE_ATTR(temp2_crit_hyst, S_IWUSR | S_IRUGO, show_temp_hyst2,
 197         set_temp_hyst2);
 198 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
 199 static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
 200 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 2);
 201 static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 3);
 202 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 4);
 203
 204 static struct attribute *max1619_attributes[] = {
 205         &dev_attr_temp1_input.attr,
 206         &dev_attr_temp2_input.attr,
 207         &dev_attr_temp2_min.attr,
 208         &dev_attr_temp2_max.attr,
 209         &dev_attr_temp2_crit.attr,
 210         &dev_attr_temp2_crit_hyst.attr,
 211
 212         &dev_attr_alarms.attr,
 213         &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
 214         &sensor_dev_attr_temp2_fault.dev_attr.attr,
 215         &sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
 216         &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
 217         NULL
 218 };
 219
 220 static const struct attribute_group max1619_group = {
 221         .attrs = max1619_attributes,
 222 };
 223
 224 /*
 225  * Real code
 226  */
 227
 228 /* Return 0 if detection is successful, -ENODEV otherwise */
 229 static int max1619_detect(struct i2c_client *new_client, int kind,
 230                           struct i2c_board_info *info)
 231 {
 232         struct i2c_adapter *adapter = new_client->adapter;
 233         u8 reg_config=0, reg_convrate=0, reg_status=0;
 234
 235         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 236                 return -ENODEV;
 237
 238         /*
 239          * Now we do the remaining detection. A negative kind means that
 240          * the driver was loaded with no force parameter (default), so we
 241          * must both detect and identify the chip. A zero kind means that
 242          * the driver was loaded with the force parameter, the detection
 243          * step shall be skipped. A positive kind means that the driver
 244          * was loaded with the force parameter and a given kind of chip is
 245          * requested, so both the detection and the identification steps
 246          * are skipped.
 247          */
 248         if (kind < 0) { /* detection */
 249                 reg_config = i2c_smbus_read_byte_data(new_client,
 250                               MAX1619_REG_R_CONFIG);
 251                 reg_convrate = i2c_smbus_read_byte_data(new_client,
 252                                MAX1619_REG_R_CONVRATE);
 253                 reg_status = i2c_smbus_read_byte_data(new_client,
 254                                 MAX1619_REG_R_STATUS);
 255                 if ((reg_config & 0x03) != 0x00
 256                  || reg_convrate > 0x07 || (reg_status & 0x61 ) !=0x00) {
 257                         dev_dbg(&adapter->dev,
 258                                 "MAX1619 detection failed at 0x%02x.\n",
 259                                 new_client->addr);
 260                         return -ENODEV;
 261                 }
 262         }
 263
 264         if (kind <= 0) { /* identification */
 265                 u8 man_id, chip_id;
 266
 267                 man_id = i2c_smbus_read_byte_data(new_client,
 268                          MAX1619_REG_R_MAN_ID);
 269                 chip_id = i2c_smbus_read_byte_data(new_client,
 270                           MAX1619_REG_R_CHIP_ID);
 271
 272                 if ((man_id == 0x4D) && (chip_id == 0x04))
 273                         kind = max1619;
 274
 275                 if (kind <= 0) { /* identification failed */
 276                         dev_info(&adapter->dev,
 277                             "Unsupported chip (man_id=0x%02X, "
 278                             "chip_id=0x%02X).\n", man_id, chip_id);
 279                         return -ENODEV;
 280                 }
 281         }
 282
 283         strlcpy(info->type, "max1619", I2C_NAME_SIZE);
 284
 285         return 0;
 286 }
 287
 288 static int max1619_probe(struct i2c_client *new_client,
 289                          const struct i2c_device_id *id)
 290 {
 291         struct max1619_data *data;
 292         int err;
 293
 294         data = kzalloc(sizeof(struct max1619_data), GFP_KERNEL);
 295         if (!data) {
 296                 err = -ENOMEM;
 297                 goto exit;
 298         }
 299
 300         i2c_set_clientdata(new_client, data);
 301         data->valid = 0;
 302         mutex_init(&data->update_lock);
 303
 304         /* Initialize the MAX1619 chip */
 305         max1619_init_client(new_client);
 306
 307         /* Register sysfs hooks */
 308         if ((err = sysfs_create_group(&new_client->dev.kobj, &max1619_group)))
 309                 goto exit_free;
 310
 311         data->hwmon_dev = hwmon_device_register(&new_client->dev);
 312         if (IS_ERR(data->hwmon_dev)) {
 313                 err = PTR_ERR(data->hwmon_dev);
 314                 goto exit_remove_files;
 315         }
 316
 317         return 0;
 318
 319 exit_remove_files:
 320         sysfs_remove_group(&new_client->dev.kobj, &max1619_group);
 321 exit_free:
 322         kfree(data);
 323 exit:
 324         return err;
 325 }
 326
 327 static void max1619_init_client(struct i2c_client *client)
 328 {
 329         u8 config;
 330
 331         /*
 332          * Start the conversions.
 333          */
 334         i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONVRATE,
 335                                   5); /* 2 Hz */
 336         config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
 337         if (config & 0x40)
 338                 i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONFIG,
 339                                           config & 0xBF); /* run */
 340 }
 341
 342 static int max1619_remove(struct i2c_client *client)
 343 {
 344         struct max1619_data *data = i2c_get_clientdata(client);
 345
 346         hwmon_device_unregister(data->hwmon_dev);
 347         sysfs_remove_group(&client->dev.kobj, &max1619_group);
 348
 349         kfree(data);
 350         return 0;
 351 }
 352
 353 static struct max1619_data *max1619_update_device(struct device *dev)
 354 {
 355         struct i2c_client *client = to_i2c_client(dev);
 356         struct max1619_data *data = i2c_get_clientdata(client);
 357
 358         mutex_lock(&data->update_lock);
 359
 360         if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
 361                 dev_dbg(&client->dev, "Updating max1619 data.\n");
 362                 data->temp_input1 = i2c_smbus_read_byte_data(client,
 363                                         MAX1619_REG_R_LOCAL_TEMP);
 364                 data->temp_input2 = i2c_smbus_read_byte_data(client,
 365                                         MAX1619_REG_R_REMOTE_TEMP);
 366                 data->temp_high2 = i2c_smbus_read_byte_data(client,
 367                                         MAX1619_REG_R_REMOTE_HIGH);
 368                 data->temp_low2 = i2c_smbus_read_byte_data(client,
 369                                         MAX1619_REG_R_REMOTE_LOW);
 370                 data->temp_crit2 = i2c_smbus_read_byte_data(client,
 371                                         MAX1619_REG_R_REMOTE_CRIT);
 372                 data->temp_hyst2 = i2c_smbus_read_byte_data(client,
 373                                         MAX1619_REG_R_TCRIT_HYST);
 374                 data->alarms = i2c_smbus_read_byte_data(client,
 375                                         MAX1619_REG_R_STATUS);
 376
 377                 data->last_updated = jiffies;
 378                 data->valid = 1;
 379         }
 380
 381         mutex_unlock(&data->update_lock);
 382
 383         return data;
 384 }
 385
 386 static int __init sensors_max1619_init(void)
 387 {
 388         return i2c_add_driver(&max1619_driver);
 389 }
 390
 391 static void __exit sensors_max1619_exit(void)
 392 {
 393         i2c_del_driver(&max1619_driver);
 394 }
 395
 396 MODULE_AUTHOR("Alexey Fisher <fishor@mail.ru> and "
 397         "Jean Delvare <khali@linux-fr.org>");
 398 MODULE_DESCRIPTION("MAX1619 sensor driver");
 399 MODULE_LICENSE("GPL");
 400
 401 module_init(sensors_max1619_init);
 402 module_exit(sensors_max1619_exit);