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/err.h>
  36 #include <linux/mutex.h>
  37 #include <linux/sysfs.h>
  38
  39 static unsigned short normal_i2c[] = { 0x18, 0x19, 0x1a,
  40                                         0x29, 0x2a, 0x2b,
  41                                         0x4c, 0x4d, 0x4e,
  42                                         I2C_CLIENT_END };
  43
  44 /*
  45  * Insmod parameters
  46  */
  47
  48 I2C_CLIENT_INSMOD_1(max1619);
  49
  50 /*
  51  * The MAX1619 registers
  52  */
  53
  54 #define MAX1619_REG_R_MAN_ID            0xFE
  55 #define MAX1619_REG_R_CHIP_ID           0xFF
  56 #define MAX1619_REG_R_CONFIG            0x03
  57 #define MAX1619_REG_W_CONFIG            0x09
  58 #define MAX1619_REG_R_CONVRATE          0x04
  59 #define MAX1619_REG_W_CONVRATE          0x0A
  60 #define MAX1619_REG_R_STATUS            0x02
  61 #define MAX1619_REG_R_LOCAL_TEMP        0x00
  62 #define MAX1619_REG_R_REMOTE_TEMP       0x01
  63 #define MAX1619_REG_R_REMOTE_HIGH       0x07
  64 #define MAX1619_REG_W_REMOTE_HIGH       0x0D
  65 #define MAX1619_REG_R_REMOTE_LOW        0x08
  66 #define MAX1619_REG_W_REMOTE_LOW        0x0E
  67 #define MAX1619_REG_R_REMOTE_CRIT       0x10
  68 #define MAX1619_REG_W_REMOTE_CRIT       0x12
  69 #define MAX1619_REG_R_TCRIT_HYST        0x11
  70 #define MAX1619_REG_W_TCRIT_HYST        0x13
  71
  72 /*
  73  * Conversions and various macros
  74  */
  75
  76 #define TEMP_FROM_REG(val)      ((val & 0x80 ? val-0x100 : val) * 1000)
  77 #define TEMP_TO_REG(val)        ((val < 0 ? val+0x100*1000 : val) / 1000)
  78
  79 /*
  80  * Functions declaration
  81  */
  82
  83 static int max1619_attach_adapter(struct i2c_adapter *adapter);
  84 static int max1619_detect(struct i2c_adapter *adapter, int address,
  85         int kind);
  86 static void max1619_init_client(struct i2c_client *client);
  87 static int max1619_detach_client(struct i2c_client *client);
  88 static struct max1619_data *max1619_update_device(struct device *dev);
  89
  90 /*
  91  * Driver data (common to all clients)
  92  */
  93
  94 static struct i2c_driver max1619_driver = {
  95         .driver = {
  96                 .name   = "max1619",
  97         },
  98         .attach_adapter = max1619_attach_adapter,
  99         .detach_client  = max1619_detach_client,
 100 };
 101
 102 /*
 103  * Client data (each client gets its own)
 104  */
 105
 106 struct max1619_data {
 107         struct i2c_client client;
 108         struct device *hwmon_dev;
 109         struct mutex update_lock;
 110         char valid; /* zero until following fields are valid */
 111         unsigned long last_updated; /* in jiffies */
 112
 113         /* registers values */
 114         u8 temp_input1; /* local */
 115         u8 temp_input2, temp_low2, temp_high2; /* remote */
 116         u8 temp_crit2;
 117         u8 temp_hyst2;
 118         u8 alarms;
 119 };
 120
 121 /*
 122  * Sysfs stuff
 123  */
 124
 125 #define show_temp(value) \
 126 static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf) \
 127 { \
 128         struct max1619_data *data = max1619_update_device(dev); \
 129         return sprintf(buf, "%d\n", TEMP_FROM_REG(data->value)); \
 130 }
 131 show_temp(temp_input1);
 132 show_temp(temp_input2);
 133 show_temp(temp_low2);
 134 show_temp(temp_high2);
 135 show_temp(temp_crit2);
 136 show_temp(temp_hyst2);
 137
 138 #define set_temp2(value, reg) \
 139 static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, \
 140         size_t count) \
 141 { \
 142         struct i2c_client *client = to_i2c_client(dev); \
 143         struct max1619_data *data = i2c_get_clientdata(client); \
 144         long val = simple_strtol(buf, NULL, 10); \
 145  \
 146         mutex_lock(&data->update_lock); \
 147         data->value = TEMP_TO_REG(val); \
 148         i2c_smbus_write_byte_data(client, reg, data->value); \
 149         mutex_unlock(&data->update_lock); \
 150         return count; \
 151 }
 152
 153 set_temp2(temp_low2, MAX1619_REG_W_REMOTE_LOW);
 154 set_temp2(temp_high2, MAX1619_REG_W_REMOTE_HIGH);
 155 set_temp2(temp_crit2, MAX1619_REG_W_REMOTE_CRIT);
 156 set_temp2(temp_hyst2, MAX1619_REG_W_TCRIT_HYST);
 157
 158 static ssize_t show_alarms(struct device *dev, struct device_attribute *attr, char *buf)
 159 {
 160         struct max1619_data *data = max1619_update_device(dev);
 161         return sprintf(buf, "%d\n", data->alarms);
 162 }
 163
 164 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
 165 static DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input2, NULL);
 166 static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_low2,
 167         set_temp_low2);
 168 static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_high2,
 169         set_temp_high2);
 170 static DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit2,
 171         set_temp_crit2);
 172 static DEVICE_ATTR(temp2_crit_hyst, S_IWUSR | S_IRUGO, show_temp_hyst2,
 173         set_temp_hyst2);
 174 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
 175
 176 static struct attribute *max1619_attributes[] = {
 177         &dev_attr_temp1_input.attr,
 178         &dev_attr_temp2_input.attr,
 179         &dev_attr_temp2_min.attr,
 180         &dev_attr_temp2_max.attr,
 181         &dev_attr_temp2_crit.attr,
 182         &dev_attr_temp2_crit_hyst.attr,
 183
 184         &dev_attr_alarms.attr,
 185         NULL
 186 };
 187
 188 static const struct attribute_group max1619_group = {
 189         .attrs = max1619_attributes,
 190 };
 191
 192 /*
 193  * Real code
 194  */
 195
 196 static int max1619_attach_adapter(struct i2c_adapter *adapter)
 197 {
 198         if (!(adapter->class & I2C_CLASS_HWMON))
 199                 return 0;
 200         return i2c_probe(adapter, &addr_data, max1619_detect);
 201 }
 202
 203 /*
 204  * The following function does more than just detection. If detection
 205  * succeeds, it also registers the new chip.
 206  */
 207 static int max1619_detect(struct i2c_adapter *adapter, int address, int kind)
 208 {
 209         struct i2c_client *new_client;
 210         struct max1619_data *data;
 211         int err = 0;
 212         const char *name = "";
 213         u8 reg_config=0, reg_convrate=0, reg_status=0;
 214
 215         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 216                 goto exit;
 217
 218         if (!(data = kzalloc(sizeof(struct max1619_data), GFP_KERNEL))) {
 219                 err = -ENOMEM;
 220                 goto exit;
 221         }
 222
 223         /* The common I2C client data is placed right before the
 224            MAX1619-specific data. */
 225         new_client = &data->client;
 226         i2c_set_clientdata(new_client, data);
 227         new_client->addr = address;
 228         new_client->adapter = adapter;
 229         new_client->driver = &max1619_driver;
 230         new_client->flags = 0;
 231
 232         /*
 233          * Now we do the remaining detection. A negative kind means that
 234          * the driver was loaded with no force parameter (default), so we
 235          * must both detect and identify the chip. A zero kind means that
 236          * the driver was loaded with the force parameter, the detection
 237          * step shall be skipped. A positive kind means that the driver
 238          * was loaded with the force parameter and a given kind of chip is
 239          * requested, so both the detection and the identification steps
 240          * are skipped.
 241          */
 242         if (kind < 0) { /* detection */
 243                 reg_config = i2c_smbus_read_byte_data(new_client,
 244                               MAX1619_REG_R_CONFIG);
 245                 reg_convrate = i2c_smbus_read_byte_data(new_client,
 246                                MAX1619_REG_R_CONVRATE);
 247                 reg_status = i2c_smbus_read_byte_data(new_client,
 248                                 MAX1619_REG_R_STATUS);
 249                 if ((reg_config & 0x03) != 0x00
 250                  || reg_convrate > 0x07 || (reg_status & 0x61 ) !=0x00) {
 251                         dev_dbg(&adapter->dev,
 252                                 "MAX1619 detection failed at 0x%02x.\n",
 253                                 address);
 254                         goto exit_free;
 255                 }
 256         }
 257
 258         if (kind <= 0) { /* identification */
 259                 u8 man_id, chip_id;
 260
 261                 man_id = i2c_smbus_read_byte_data(new_client,
 262                          MAX1619_REG_R_MAN_ID);
 263                 chip_id = i2c_smbus_read_byte_data(new_client,
 264                           MAX1619_REG_R_CHIP_ID);
 265
 266                 if ((man_id == 0x4D) && (chip_id == 0x04))
 267                         kind = max1619;
 268
 269                 if (kind <= 0) { /* identification failed */
 270                         dev_info(&adapter->dev,
 271                             "Unsupported chip (man_id=0x%02X, "
 272                             "chip_id=0x%02X).\n", man_id, chip_id);
 273                         goto exit_free;
 274                 }
 275         }
 276
 277         if (kind == max1619)
 278                 name = "max1619";
 279
 280         /* We can fill in the remaining client fields */
 281         strlcpy(new_client->name, name, I2C_NAME_SIZE);
 282         data->valid = 0;
 283         mutex_init(&data->update_lock);
 284
 285         /* Tell the I2C layer a new client has arrived */
 286         if ((err = i2c_attach_client(new_client)))
 287                 goto exit_free;
 288
 289         /* Initialize the MAX1619 chip */
 290         max1619_init_client(new_client);
 291
 292         /* Register sysfs hooks */
 293         if ((err = sysfs_create_group(&new_client->dev.kobj, &max1619_group)))
 294                 goto exit_detach;
 295
 296         data->hwmon_dev = hwmon_device_register(&new_client->dev);
 297         if (IS_ERR(data->hwmon_dev)) {
 298                 err = PTR_ERR(data->hwmon_dev);
 299                 goto exit_remove_files;
 300         }
 301
 302         return 0;
 303
 304 exit_remove_files:
 305         sysfs_remove_group(&new_client->dev.kobj, &max1619_group);
 306 exit_detach:
 307         i2c_detach_client(new_client);
 308 exit_free:
 309         kfree(data);
 310 exit:
 311         return err;
 312 }
 313
 314 static void max1619_init_client(struct i2c_client *client)
 315 {
 316         u8 config;
 317
 318         /*
 319          * Start the conversions.
 320          */
 321         i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONVRATE,
 322                                   5); /* 2 Hz */
 323         config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
 324         if (config & 0x40)
 325                 i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONFIG,
 326                                           config & 0xBF); /* run */
 327 }
 328
 329 static int max1619_detach_client(struct i2c_client *client)
 330 {
 331         struct max1619_data *data = i2c_get_clientdata(client);
 332         int err;
 333
 334         hwmon_device_unregister(data->hwmon_dev);
 335         sysfs_remove_group(&client->dev.kobj, &max1619_group);
 336
 337         if ((err = i2c_detach_client(client)))
 338                 return err;
 339
 340         kfree(data);
 341         return 0;
 342 }
 343
 344 static struct max1619_data *max1619_update_device(struct device *dev)
 345 {
 346         struct i2c_client *client = to_i2c_client(dev);
 347         struct max1619_data *data = i2c_get_clientdata(client);
 348
 349         mutex_lock(&data->update_lock);
 350
 351         if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
 352                 dev_dbg(&client->dev, "Updating max1619 data.\n");
 353                 data->temp_input1 = i2c_smbus_read_byte_data(client,
 354                                         MAX1619_REG_R_LOCAL_TEMP);
 355                 data->temp_input2 = i2c_smbus_read_byte_data(client,
 356                                         MAX1619_REG_R_REMOTE_TEMP);
 357                 data->temp_high2 = i2c_smbus_read_byte_data(client,
 358                                         MAX1619_REG_R_REMOTE_HIGH);
 359                 data->temp_low2 = i2c_smbus_read_byte_data(client,
 360                                         MAX1619_REG_R_REMOTE_LOW);
 361                 data->temp_crit2 = i2c_smbus_read_byte_data(client,
 362                                         MAX1619_REG_R_REMOTE_CRIT);
 363                 data->temp_hyst2 = i2c_smbus_read_byte_data(client,
 364                                         MAX1619_REG_R_TCRIT_HYST);
 365                 data->alarms = i2c_smbus_read_byte_data(client,
 366                                         MAX1619_REG_R_STATUS);
 367
 368                 data->last_updated = jiffies;
 369                 data->valid = 1;
 370         }
 371
 372         mutex_unlock(&data->update_lock);
 373
 374         return data;
 375 }
 376
 377 static int __init sensors_max1619_init(void)
 378 {
 379         return i2c_add_driver(&max1619_driver);
 380 }
 381
 382 static void __exit sensors_max1619_exit(void)
 383 {
 384         i2c_del_driver(&max1619_driver);
 385 }
 386
 387 MODULE_AUTHOR("Alexey Fisher <fishor@mail.ru> and "
 388         "Jean Delvare <khali@linux-fr.org>");
 389 MODULE_DESCRIPTION("MAX1619 sensor driver");
 390 MODULE_LICENSE("GPL");
 391
 392 module_init(sensors_max1619_init);
 393 module_exit(sensors_max1619_exit);