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, \
 137                             char *buf) \
 138 { \
 139         struct max1619_data *data = max1619_update_device(dev); \
 140         return sprintf(buf, "%d\n", temp_from_reg(data->value)); \
 141 }
 142 show_temp(temp_input1);
 143 show_temp(temp_input2);
 144 show_temp(temp_low2);
 145 show_temp(temp_high2);
 146 show_temp(temp_crit2);
 147 show_temp(temp_hyst2);
 148
 149 #define set_temp2(value, reg) \
 150 static ssize_t set_##value(struct device *dev, struct device_attribute *attr, \
 151                            const char *buf, \
 152         size_t count) \
 153 { \
 154         struct i2c_client *client = to_i2c_client(dev); \
 155         struct max1619_data *data = i2c_get_clientdata(client); \
 156         long val; \
 157         int err = kstrtol(buf, 10, &val); \
 158         if (err) \
 159                 return err; \
 160 \
 161         mutex_lock(&data->update_lock); \
 162         data->value = temp_to_reg(val); \
 163         i2c_smbus_write_byte_data(client, reg, data->value); \
 164         mutex_unlock(&data->update_lock); \
 165         return count; \
 166 }
 167
 168 set_temp2(temp_low2, MAX1619_REG_W_REMOTE_LOW);
 169 set_temp2(temp_high2, MAX1619_REG_W_REMOTE_HIGH);
 170 set_temp2(temp_crit2, MAX1619_REG_W_REMOTE_CRIT);
 171 set_temp2(temp_hyst2, MAX1619_REG_W_TCRIT_HYST);
 172
 173 static ssize_t show_alarms(struct device *dev, struct device_attribute *attr,
 174                            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 *client,
 230                           struct i2c_board_info *info)
 231 {
 232         struct i2c_adapter *adapter = client->adapter;
 233         u8 reg_config, reg_convrate, reg_status, man_id, chip_id;
 234
 235         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 236                 return -ENODEV;
 237
 238         /* detection */
 239         reg_config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
 240         reg_convrate = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONVRATE);
 241         reg_status = i2c_smbus_read_byte_data(client, MAX1619_REG_R_STATUS);
 242         if ((reg_config & 0x03) != 0x00
 243          || reg_convrate > 0x07 || (reg_status & 0x61) != 0x00) {
 244                 dev_dbg(&adapter->dev, "MAX1619 detection failed at 0x%02x\n",
 245                         client->addr);
 246                 return -ENODEV;
 247         }
 248
 249         /* identification */
 250         man_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_MAN_ID);
 251         chip_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CHIP_ID);
 252         if (man_id != 0x4D || chip_id != 0x04) {
 253                 dev_info(&adapter->dev,
 254                          "Unsupported chip (man_id=0x%02X, chip_id=0x%02X).\n",
 255                          man_id, chip_id);
 256                 return -ENODEV;
 257         }
 258
 259         strlcpy(info->type, "max1619", I2C_NAME_SIZE);
 260
 261         return 0;
 262 }
 263
 264 static int max1619_probe(struct i2c_client *new_client,
 265                          const struct i2c_device_id *id)
 266 {
 267         struct max1619_data *data;
 268         int err;
 269
 270         data = kzalloc(sizeof(struct max1619_data), GFP_KERNEL);
 271         if (!data) {
 272                 err = -ENOMEM;
 273                 goto exit;
 274         }
 275
 276         i2c_set_clientdata(new_client, data);
 277         data->valid = 0;
 278         mutex_init(&data->update_lock);
 279
 280         /* Initialize the MAX1619 chip */
 281         max1619_init_client(new_client);
 282
 283         /* Register sysfs hooks */
 284         err = sysfs_create_group(&new_client->dev.kobj, &max1619_group);
 285         if (err)
 286                 goto exit_free;
 287
 288         data->hwmon_dev = hwmon_device_register(&new_client->dev);
 289         if (IS_ERR(data->hwmon_dev)) {
 290                 err = PTR_ERR(data->hwmon_dev);
 291                 goto exit_remove_files;
 292         }
 293
 294         return 0;
 295
 296 exit_remove_files:
 297         sysfs_remove_group(&new_client->dev.kobj, &max1619_group);
 298 exit_free:
 299         kfree(data);
 300 exit:
 301         return err;
 302 }
 303
 304 static void max1619_init_client(struct i2c_client *client)
 305 {
 306         u8 config;
 307
 308         /*
 309          * Start the conversions.
 310          */
 311         i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONVRATE,
 312                                   5); /* 2 Hz */
 313         config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
 314         if (config & 0x40)
 315                 i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONFIG,
 316                                           config & 0xBF); /* run */
 317 }
 318
 319 static int max1619_remove(struct i2c_client *client)
 320 {
 321         struct max1619_data *data = i2c_get_clientdata(client);
 322
 323         hwmon_device_unregister(data->hwmon_dev);
 324         sysfs_remove_group(&client->dev.kobj, &max1619_group);
 325
 326         kfree(data);
 327         return 0;
 328 }
 329
 330 static struct max1619_data *max1619_update_device(struct device *dev)
 331 {
 332         struct i2c_client *client = to_i2c_client(dev);
 333         struct max1619_data *data = i2c_get_clientdata(client);
 334
 335         mutex_lock(&data->update_lock);
 336
 337         if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
 338                 dev_dbg(&client->dev, "Updating max1619 data.\n");
 339                 data->temp_input1 = i2c_smbus_read_byte_data(client,
 340                                         MAX1619_REG_R_LOCAL_TEMP);
 341                 data->temp_input2 = i2c_smbus_read_byte_data(client,
 342                                         MAX1619_REG_R_REMOTE_TEMP);
 343                 data->temp_high2 = i2c_smbus_read_byte_data(client,
 344                                         MAX1619_REG_R_REMOTE_HIGH);
 345                 data->temp_low2 = i2c_smbus_read_byte_data(client,
 346                                         MAX1619_REG_R_REMOTE_LOW);
 347                 data->temp_crit2 = i2c_smbus_read_byte_data(client,
 348                                         MAX1619_REG_R_REMOTE_CRIT);
 349                 data->temp_hyst2 = i2c_smbus_read_byte_data(client,
 350                                         MAX1619_REG_R_TCRIT_HYST);
 351                 data->alarms = i2c_smbus_read_byte_data(client,
 352                                         MAX1619_REG_R_STATUS);
 353
 354                 data->last_updated = jiffies;
 355                 data->valid = 1;
 356         }
 357
 358         mutex_unlock(&data->update_lock);
 359
 360         return data;
 361 }
 362
 363 module_i2c_driver(max1619_driver);
 364
 365 MODULE_AUTHOR("Alexey Fisher <fishor@mail.ru> and "
 366         "Jean Delvare <khali@linux-fr.org>");
 367 MODULE_DESCRIPTION("MAX1619 sensor driver");
 368 MODULE_LICENSE("GPL");