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