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
  37 static unsigned short normal_i2c[] = { 0x18, 0x19, 0x1a,
  38                                         0x29, 0x2a, 0x2b,
  39                                         0x4c, 0x4d, 0x4e,
  40                                         I2C_CLIENT_END };
  41
  42 /*
  43  * Insmod parameters
  44  */
  45
  46 I2C_CLIENT_INSMOD_1(max1619);
  47
  48 /*
  49  * The MAX1619 registers
  50  */
  51
  52 #define MAX1619_REG_R_MAN_ID            0xFE
  53 #define MAX1619_REG_R_CHIP_ID           0xFF
  54 #define MAX1619_REG_R_CONFIG            0x03
  55 #define MAX1619_REG_W_CONFIG            0x09
  56 #define MAX1619_REG_R_CONVRATE          0x04
  57 #define MAX1619_REG_W_CONVRATE          0x0A
  58 #define MAX1619_REG_R_STATUS            0x02
  59 #define MAX1619_REG_R_LOCAL_TEMP        0x00
  60 #define MAX1619_REG_R_REMOTE_TEMP       0x01
  61 #define MAX1619_REG_R_REMOTE_HIGH       0x07
  62 #define MAX1619_REG_W_REMOTE_HIGH       0x0D
  63 #define MAX1619_REG_R_REMOTE_LOW        0x08
  64 #define MAX1619_REG_W_REMOTE_LOW        0x0E
  65 #define MAX1619_REG_R_REMOTE_CRIT       0x10
  66 #define MAX1619_REG_W_REMOTE_CRIT       0x12
  67 #define MAX1619_REG_R_TCRIT_HYST        0x11
  68 #define MAX1619_REG_W_TCRIT_HYST        0x13
  69
  70 /*
  71  * Conversions and various macros
  72  */
  73
  74 #define TEMP_FROM_REG(val)      ((val & 0x80 ? val-0x100 : val) * 1000)
  75 #define TEMP_TO_REG(val)        ((val < 0 ? val+0x100*1000 : val) / 1000)
  76
  77 /*
  78  * Functions declaration
  79  */
  80
  81 static int max1619_attach_adapter(struct i2c_adapter *adapter);
  82 static int max1619_detect(struct i2c_adapter *adapter, int address,
  83         int kind);
  84 static void max1619_init_client(struct i2c_client *client);
  85 static int max1619_detach_client(struct i2c_client *client);
  86 static struct max1619_data *max1619_update_device(struct device *dev);
  87
  88 /*
  89  * Driver data (common to all clients)
  90  */
  91
  92 static struct i2c_driver max1619_driver = {
  93         .owner          = THIS_MODULE,
  94         .name           = "max1619",
  95         .flags          = I2C_DF_NOTIFY,
  96         .attach_adapter = max1619_attach_adapter,
  97         .detach_client  = max1619_detach_client,
  98 };
  99
 100 /*
 101  * Client data (each client gets its own)
 102  */
 103
 104 struct max1619_data {
 105         struct i2c_client client;
 106         struct class_device *class_dev;
 107         struct semaphore update_lock;
 108         char valid; /* zero until following fields are valid */
 109         unsigned long last_updated; /* in jiffies */
 110
 111         /* registers values */
 112         u8 temp_input1; /* local */
 113         u8 temp_input2, temp_low2, temp_high2; /* remote */
 114         u8 temp_crit2;
 115         u8 temp_hyst2;
 116         u8 alarms;
 117 };
 118
 119 /*
 120  * Sysfs stuff
 121  */
 122
 123 #define show_temp(value) \
 124 static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf) \
 125 { \
 126         struct max1619_data *data = max1619_update_device(dev); \
 127         return sprintf(buf, "%d\n", TEMP_FROM_REG(data->value)); \
 128 }
 129 show_temp(temp_input1);
 130 show_temp(temp_input2);
 131 show_temp(temp_low2);
 132 show_temp(temp_high2);
 133 show_temp(temp_crit2);
 134 show_temp(temp_hyst2);
 135
 136 #define set_temp2(value, reg) \
 137 static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, \
 138         size_t count) \
 139 { \
 140         struct i2c_client *client = to_i2c_client(dev); \
 141         struct max1619_data *data = i2c_get_clientdata(client); \
 142         long val = simple_strtol(buf, NULL, 10); \
 143  \
 144         down(&data->update_lock); \
 145         data->value = TEMP_TO_REG(val); \
 146         i2c_smbus_write_byte_data(client, reg, data->value); \
 147         up(&data->update_lock); \
 148         return count; \
 149 }
 150
 151 set_temp2(temp_low2, MAX1619_REG_W_REMOTE_LOW);
 152 set_temp2(temp_high2, MAX1619_REG_W_REMOTE_HIGH);
 153 set_temp2(temp_crit2, MAX1619_REG_W_REMOTE_CRIT);
 154 set_temp2(temp_hyst2, MAX1619_REG_W_TCRIT_HYST);
 155
 156 static ssize_t show_alarms(struct device *dev, struct device_attribute *attr, char *buf)
 157 {
 158         struct max1619_data *data = max1619_update_device(dev);
 159         return sprintf(buf, "%d\n", data->alarms);
 160 }
 161
 162 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
 163 static DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input2, NULL);
 164 static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_low2,
 165         set_temp_low2);
 166 static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_high2,
 167         set_temp_high2);
 168 static DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit2,
 169         set_temp_crit2);
 170 static DEVICE_ATTR(temp2_crit_hyst, S_IWUSR | S_IRUGO, show_temp_hyst2,
 171         set_temp_hyst2);
 172 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
 173
 174 /*
 175  * Real code
 176  */
 177
 178 static int max1619_attach_adapter(struct i2c_adapter *adapter)
 179 {
 180         if (!(adapter->class & I2C_CLASS_HWMON))
 181                 return 0;
 182         return i2c_probe(adapter, &addr_data, max1619_detect);
 183 }
 184
 185 /*
 186  * The following function does more than just detection. If detection
 187  * succeeds, it also registers the new chip.
 188  */
 189 static int max1619_detect(struct i2c_adapter *adapter, int address, int kind)
 190 {
 191         struct i2c_client *new_client;
 192         struct max1619_data *data;
 193         int err = 0;
 194         const char *name = "";
 195         u8 reg_config=0, reg_convrate=0, reg_status=0;
 196
 197         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 198                 goto exit;
 199
 200         if (!(data = kzalloc(sizeof(struct max1619_data), GFP_KERNEL))) {
 201                 err = -ENOMEM;
 202                 goto exit;
 203         }
 204
 205         /* The common I2C client data is placed right before the
 206            MAX1619-specific data. */
 207         new_client = &data->client;
 208         i2c_set_clientdata(new_client, data);
 209         new_client->addr = address;
 210         new_client->adapter = adapter;
 211         new_client->driver = &max1619_driver;
 212         new_client->flags = 0;
 213
 214         /*
 215          * Now we do the remaining detection. A negative kind means that
 216          * the driver was loaded with no force parameter (default), so we
 217          * must both detect and identify the chip. A zero kind means that
 218          * the driver was loaded with the force parameter, the detection
 219          * step shall be skipped. A positive kind means that the driver
 220          * was loaded with the force parameter and a given kind of chip is
 221          * requested, so both the detection and the identification steps
 222          * are skipped.
 223          */
 224         if (kind < 0) { /* detection */
 225                 reg_config = i2c_smbus_read_byte_data(new_client,
 226                               MAX1619_REG_R_CONFIG);
 227                 reg_convrate = i2c_smbus_read_byte_data(new_client,
 228                                MAX1619_REG_R_CONVRATE);
 229                 reg_status = i2c_smbus_read_byte_data(new_client,
 230                                 MAX1619_REG_R_STATUS);
 231                 if ((reg_config & 0x03) != 0x00
 232                  || reg_convrate > 0x07 || (reg_status & 0x61 ) !=0x00) {
 233                         dev_dbg(&adapter->dev,
 234                                 "MAX1619 detection failed at 0x%02x.\n",
 235                                 address);
 236                         goto exit_free;
 237                 }
 238         }
 239
 240         if (kind <= 0) { /* identification */
 241                 u8 man_id, chip_id;
 242
 243                 man_id = i2c_smbus_read_byte_data(new_client,
 244                          MAX1619_REG_R_MAN_ID);
 245                 chip_id = i2c_smbus_read_byte_data(new_client,
 246                           MAX1619_REG_R_CHIP_ID);
 247
 248                 if ((man_id == 0x4D) && (chip_id == 0x04))
 249                         kind = max1619;
 250
 251                 if (kind <= 0) { /* identification failed */
 252                         dev_info(&adapter->dev,
 253                             "Unsupported chip (man_id=0x%02X, "
 254                             "chip_id=0x%02X).\n", man_id, chip_id);
 255                         goto exit_free;
 256                 }
 257         }
 258
 259         if (kind == max1619)
 260                 name = "max1619";
 261
 262         /* We can fill in the remaining client fields */
 263         strlcpy(new_client->name, name, I2C_NAME_SIZE);
 264         data->valid = 0;
 265         init_MUTEX(&data->update_lock);
 266
 267         /* Tell the I2C layer a new client has arrived */
 268         if ((err = i2c_attach_client(new_client)))
 269                 goto exit_free;
 270
 271         /* Initialize the MAX1619 chip */
 272         max1619_init_client(new_client);
 273
 274         /* Register sysfs hooks */
 275         data->class_dev = hwmon_device_register(&new_client->dev);
 276         if (IS_ERR(data->class_dev)) {
 277                 err = PTR_ERR(data->class_dev);
 278                 goto exit_detach;
 279         }
 280
 281         device_create_file(&new_client->dev, &dev_attr_temp1_input);
 282         device_create_file(&new_client->dev, &dev_attr_temp2_input);
 283         device_create_file(&new_client->dev, &dev_attr_temp2_min);
 284         device_create_file(&new_client->dev, &dev_attr_temp2_max);
 285         device_create_file(&new_client->dev, &dev_attr_temp2_crit);
 286         device_create_file(&new_client->dev, &dev_attr_temp2_crit_hyst);
 287         device_create_file(&new_client->dev, &dev_attr_alarms);
 288
 289         return 0;
 290
 291 exit_detach:
 292         i2c_detach_client(new_client);
 293 exit_free:
 294         kfree(data);
 295 exit:
 296         return err;
 297 }
 298
 299 static void max1619_init_client(struct i2c_client *client)
 300 {
 301         u8 config;
 302
 303         /*
 304          * Start the conversions.
 305          */
 306         i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONVRATE,
 307                                   5); /* 2 Hz */
 308         config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
 309         if (config & 0x40)
 310                 i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONFIG,
 311                                           config & 0xBF); /* run */
 312 }
 313
 314 static int max1619_detach_client(struct i2c_client *client)
 315 {
 316         struct max1619_data *data = i2c_get_clientdata(client);
 317         int err;
 318
 319         hwmon_device_unregister(data->class_dev);
 320
 321         if ((err = i2c_detach_client(client)))
 322                 return err;
 323
 324         kfree(data);
 325         return 0;
 326 }
 327
 328 static struct max1619_data *max1619_update_device(struct device *dev)
 329 {
 330         struct i2c_client *client = to_i2c_client(dev);
 331         struct max1619_data *data = i2c_get_clientdata(client);
 332
 333         down(&data->update_lock);
 334
 335         if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
 336                 dev_dbg(&client->dev, "Updating max1619 data.\n");
 337                 data->temp_input1 = i2c_smbus_read_byte_data(client,
 338                                         MAX1619_REG_R_LOCAL_TEMP);
 339                 data->temp_input2 = i2c_smbus_read_byte_data(client,
 340                                         MAX1619_REG_R_REMOTE_TEMP);
 341                 data->temp_high2 = i2c_smbus_read_byte_data(client,
 342                                         MAX1619_REG_R_REMOTE_HIGH);
 343                 data->temp_low2 = i2c_smbus_read_byte_data(client,
 344                                         MAX1619_REG_R_REMOTE_LOW);
 345                 data->temp_crit2 = i2c_smbus_read_byte_data(client,
 346                                         MAX1619_REG_R_REMOTE_CRIT);
 347                 data->temp_hyst2 = i2c_smbus_read_byte_data(client,
 348                                         MAX1619_REG_R_TCRIT_HYST);
 349                 data->alarms = i2c_smbus_read_byte_data(client,
 350                                         MAX1619_REG_R_STATUS);
 351
 352                 data->last_updated = jiffies;
 353                 data->valid = 1;
 354         }
 355
 356         up(&data->update_lock);
 357
 358         return data;
 359 }
 360
 361 static int __init sensors_max1619_init(void)
 362 {
 363         return i2c_add_driver(&max1619_driver);
 364 }
 365
 366 static void __exit sensors_max1619_exit(void)
 367 {
 368         i2c_del_driver(&max1619_driver);
 369 }
 370
 371 MODULE_AUTHOR("Alexey Fisher <fishor@mail.ru> and "
 372         "Jean Delvare <khali@linux-fr.org>");
 373 MODULE_DESCRIPTION("MAX1619 sensor driver");
 374 MODULE_LICENSE("GPL");
 375
 376 module_init(sensors_max1619_init);
 377 module_exit(sensors_max1619_exit);