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  * The MAX1619 registers
  45  */
  46
  47 #define MAX1619_REG_R_MAN_ID            0xFE
  48 #define MAX1619_REG_R_CHIP_ID           0xFF
  49 #define MAX1619_REG_R_CONFIG            0x03
  50 #define MAX1619_REG_W_CONFIG            0x09
  51 #define MAX1619_REG_R_CONVRATE          0x04
  52 #define MAX1619_REG_W_CONVRATE          0x0A
  53 #define MAX1619_REG_R_STATUS            0x02
  54 #define MAX1619_REG_R_LOCAL_TEMP        0x00
  55 #define MAX1619_REG_R_REMOTE_TEMP       0x01
  56 #define MAX1619_REG_R_REMOTE_HIGH       0x07
  57 #define MAX1619_REG_W_REMOTE_HIGH       0x0D
  58 #define MAX1619_REG_R_REMOTE_LOW        0x08
  59 #define MAX1619_REG_W_REMOTE_LOW        0x0E
  60 #define MAX1619_REG_R_REMOTE_CRIT       0x10
  61 #define MAX1619_REG_W_REMOTE_CRIT       0x12
  62 #define MAX1619_REG_R_TCRIT_HYST        0x11
  63 #define MAX1619_REG_W_TCRIT_HYST        0x13
  64
  65 /*
  66  * Conversions
  67  */
  68
  69 static int temp_from_reg(int val)
  70 {
  71         return (val & 0x80 ? val-0x100 : val) * 1000;
  72 }
  73
  74 static int temp_to_reg(int val)
  75 {
  76         return (val < 0 ? val+0x100*1000 : val) / 1000;
  77 }
  78
  79 /*
  80  * Functions declaration
  81  */
  82
  83 static int max1619_probe(struct i2c_client *client,
  84                          const struct i2c_device_id *id);
  85 static int max1619_detect(struct i2c_client *client,
  86                           struct i2c_board_info *info);
  87 static void max1619_init_client(struct i2c_client *client);
  88 static int max1619_remove(struct i2c_client *client);
  89 static struct max1619_data *max1619_update_device(struct device *dev);
  90
  91 /*
  92  * Driver data (common to all clients)
  93  */
  94
  95 static const struct i2c_device_id max1619_id[] = {
  96         { "max1619", 0 },
  97         { }
  98 };
  99 MODULE_DEVICE_TABLE(i2c, max1619_id);
 100
 101 static struct i2c_driver max1619_driver = {
 102         .class          = I2C_CLASS_HWMON,
 103         .driver = {
 104                 .name   = "max1619",
 105         },
 106         .probe          = max1619_probe,
 107         .remove         = max1619_remove,
 108         .id_table       = max1619_id,
 109         .detect         = max1619_detect,
 110         .address_list   = normal_i2c,
 111 };
 112
 113 /*
 114  * Client data (each client gets its own)
 115  */
 116
 117 struct max1619_data {
 118         struct device *hwmon_dev;
 119         struct mutex update_lock;
 120         char valid; /* zero until following fields are valid */
 121         unsigned long last_updated; /* in jiffies */
 122
 123         /* registers values */
 124         u8 temp_input1; /* local */
 125         u8 temp_input2, temp_low2, temp_high2; /* remote */
 126         u8 temp_crit2;
 127         u8 temp_hyst2;
 128         u8 alarms;
 129 };
 130
 131 /*
 132  * Sysfs stuff
 133  */
 134
 135 #define show_temp(value) \
 136 static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf) \
 137 { \
 138         struct max1619_data *data = max1619_update_device(dev); \
 139         return sprintf(buf, "%d\n", temp_from_reg(data->value)); \
 140 }
 141 show_temp(temp_input1);
 142 show_temp(temp_input2);
 143 show_temp(temp_low2);
 144 show_temp(temp_high2);
 145 show_temp(temp_crit2);
 146 show_temp(temp_hyst2);
 147
 148 #define set_temp2(value, reg) \
 149 static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, \
 150         size_t count) \
 151 { \
 152         struct i2c_client *client = to_i2c_client(dev); \
 153         struct max1619_data *data = i2c_get_clientdata(client); \
 154         long val = simple_strtol(buf, NULL, 10); \
 155  \
 156         mutex_lock(&data->update_lock); \
 157         data->value = temp_to_reg(val); \
 158         i2c_smbus_write_byte_data(client, reg, data->value); \
 159         mutex_unlock(&data->update_lock); \
 160         return count; \
 161 }
 162
 163 set_temp2(temp_low2, MAX1619_REG_W_REMOTE_LOW);
 164 set_temp2(temp_high2, MAX1619_REG_W_REMOTE_HIGH);
 165 set_temp2(temp_crit2, MAX1619_REG_W_REMOTE_CRIT);
 166 set_temp2(temp_hyst2, MAX1619_REG_W_TCRIT_HYST);
 167
 168 static ssize_t show_alarms(struct device *dev, struct device_attribute *attr, char *buf)
 169 {
 170         struct max1619_data *data = max1619_update_device(dev);
 171         return sprintf(buf, "%d\n", data->alarms);
 172 }
 173
 174 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
 175                           char *buf)
 176 {
 177         int bitnr = to_sensor_dev_attr(attr)->index;
 178         struct max1619_data *data = max1619_update_device(dev);
 179         return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
 180 }
 181
 182 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
 183 static DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input2, NULL);
 184 static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_low2,
 185         set_temp_low2);
 186 static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_high2,
 187         set_temp_high2);
 188 static DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit2,
 189         set_temp_crit2);
 190 static DEVICE_ATTR(temp2_crit_hyst, S_IWUSR | S_IRUGO, show_temp_hyst2,
 191         set_temp_hyst2);
 192 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
 193 static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
 194 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 2);
 195 static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 3);
 196 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 4);
 197
 198 static struct attribute *max1619_attributes[] = {
 199         &dev_attr_temp1_input.attr,
 200         &dev_attr_temp2_input.attr,
 201         &dev_attr_temp2_min.attr,
 202         &dev_attr_temp2_max.attr,
 203         &dev_attr_temp2_crit.attr,
 204         &dev_attr_temp2_crit_hyst.attr,
 205
 206         &dev_attr_alarms.attr,
 207         &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
 208         &sensor_dev_attr_temp2_fault.dev_attr.attr,
 209         &sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
 210         &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
 211         NULL
 212 };
 213
 214 static const struct attribute_group max1619_group = {
 215         .attrs = max1619_attributes,
 216 };
 217
 218 /*
 219  * Real code
 220  */
 221
 222 /* Return 0 if detection is successful, -ENODEV otherwise */
 223 static int max1619_detect(struct i2c_client *client,
 224                           struct i2c_board_info *info)
 225 {
 226         struct i2c_adapter *adapter = client->adapter;
 227         u8 reg_config, reg_convrate, reg_status, man_id, chip_id;
 228
 229         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 230                 return -ENODEV;
 231
 232         /* detection */
 233         reg_config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
 234         reg_convrate = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONVRATE);
 235         reg_status = i2c_smbus_read_byte_data(client, MAX1619_REG_R_STATUS);
 236         if ((reg_config & 0x03) != 0x00
 237          || reg_convrate > 0x07 || (reg_status & 0x61) != 0x00) {
 238                 dev_dbg(&adapter->dev, "MAX1619 detection failed at 0x%02x\n",
 239                         client->addr);
 240                 return -ENODEV;
 241         }
 242
 243         /* identification */
 244         man_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_MAN_ID);
 245         chip_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CHIP_ID);
 246         if (man_id != 0x4D || chip_id != 0x04) {
 247                 dev_info(&adapter->dev,
 248                          "Unsupported chip (man_id=0x%02X, chip_id=0x%02X).\n",
 249                          man_id, chip_id);
 250                 return -ENODEV;
 251         }
 252
 253         strlcpy(info->type, "max1619", I2C_NAME_SIZE);
 254
 255         return 0;
 256 }
 257
 258 static int max1619_probe(struct i2c_client *new_client,
 259                          const struct i2c_device_id *id)
 260 {
 261         struct max1619_data *data;
 262         int err;
 263
 264         data = kzalloc(sizeof(struct max1619_data), GFP_KERNEL);
 265         if (!data) {
 266                 err = -ENOMEM;
 267                 goto exit;
 268         }
 269
 270         i2c_set_clientdata(new_client, data);
 271         data->valid = 0;
 272         mutex_init(&data->update_lock);
 273
 274         /* Initialize the MAX1619 chip */
 275         max1619_init_client(new_client);
 276
 277         /* Register sysfs hooks */
 278         if ((err = sysfs_create_group(&new_client->dev.kobj, &max1619_group)))
 279                 goto exit_free;
 280
 281         data->hwmon_dev = hwmon_device_register(&new_client->dev);
 282         if (IS_ERR(data->hwmon_dev)) {
 283                 err = PTR_ERR(data->hwmon_dev);
 284                 goto exit_remove_files;
 285         }
 286
 287         return 0;
 288
 289 exit_remove_files:
 290         sysfs_remove_group(&new_client->dev.kobj, &max1619_group);
 291 exit_free:
 292         kfree(data);
 293 exit:
 294         return err;
 295 }
 296
 297 static void max1619_init_client(struct i2c_client *client)
 298 {
 299         u8 config;
 300
 301         /*
 302          * Start the conversions.
 303          */
 304         i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONVRATE,
 305                                   5); /* 2 Hz */
 306         config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
 307         if (config & 0x40)
 308                 i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONFIG,
 309                                           config & 0xBF); /* run */
 310 }
 311
 312 static int max1619_remove(struct i2c_client *client)
 313 {
 314         struct max1619_data *data = i2c_get_clientdata(client);
 315
 316         hwmon_device_unregister(data->hwmon_dev);
 317         sysfs_remove_group(&client->dev.kobj, &max1619_group);
 318
 319         kfree(data);
 320         return 0;
 321 }
 322
 323 static struct max1619_data *max1619_update_device(struct device *dev)
 324 {
 325         struct i2c_client *client = to_i2c_client(dev);
 326         struct max1619_data *data = i2c_get_clientdata(client);
 327
 328         mutex_lock(&data->update_lock);
 329
 330         if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
 331                 dev_dbg(&client->dev, "Updating max1619 data.\n");
 332                 data->temp_input1 = i2c_smbus_read_byte_data(client,
 333                                         MAX1619_REG_R_LOCAL_TEMP);
 334                 data->temp_input2 = i2c_smbus_read_byte_data(client,
 335                                         MAX1619_REG_R_REMOTE_TEMP);
 336                 data->temp_high2 = i2c_smbus_read_byte_data(client,
 337                                         MAX1619_REG_R_REMOTE_HIGH);
 338                 data->temp_low2 = i2c_smbus_read_byte_data(client,
 339                                         MAX1619_REG_R_REMOTE_LOW);
 340                 data->temp_crit2 = i2c_smbus_read_byte_data(client,
 341                                         MAX1619_REG_R_REMOTE_CRIT);
 342                 data->temp_hyst2 = i2c_smbus_read_byte_data(client,
 343                                         MAX1619_REG_R_TCRIT_HYST);
 344                 data->alarms = i2c_smbus_read_byte_data(client,
 345                                         MAX1619_REG_R_STATUS);
 346
 347                 data->last_updated = jiffies;
 348                 data->valid = 1;
 349         }
 350
 351         mutex_unlock(&data->update_lock);
 352
 353         return data;
 354 }
 355
 356 static int __init sensors_max1619_init(void)
 357 {
 358         return i2c_add_driver(&max1619_driver);
 359 }
 360
 361 static void __exit sensors_max1619_exit(void)
 362 {
 363         i2c_del_driver(&max1619_driver);
 364 }
 365
 366 MODULE_AUTHOR("Alexey Fisher <fishor@mail.ru> and "
 367         "Jean Delvare <khali@linux-fr.org>");
 368 MODULE_DESCRIPTION("MAX1619 sensor driver");
 369 MODULE_LICENSE("GPL");
 370
 371 module_init(sensors_max1619_init);
 372 module_exit(sensors_max1619_exit);