1/* 2 * lm95241.c - Part of lm_sensors, Linux kernel modules for hardware 3 * monitoring 4 * Copyright (C) 2008 Davide Rizzo <elpa-rizzo@gmail.com> 5 * 6 * Based on the max1619 driver. The LM95241 is a sensor chip made by National 7 * Semiconductors. 8 * It reports up to three temperatures (its own plus up to 9 * two external ones). Complete datasheet can be 10 * obtained from National's website at: 11 * http://www.national.com/ds.cgi/LM/LM95241.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#include <linux/module.h> 29#include <linux/init.h> 30#include <linux/slab.h> 31#include <linux/jiffies.h> 32#include <linux/i2c.h> 33#include <linux/hwmon.h> 34#include <linux/hwmon-sysfs.h> 35#include <linux/err.h> 36#include <linux/mutex.h> 37#include <linux/sysfs.h> 38 39static const unsigned short normal_i2c[] = { 40 0x19, 0x2a, 0x2b, I2C_CLIENT_END}; 41 42/* LM95241 registers */ 43#define LM95241_REG_R_MAN_ID 0xFE 44#define LM95241_REG_R_CHIP_ID 0xFF 45#define LM95241_REG_R_STATUS 0x02 46#define LM95241_REG_RW_CONFIG 0x03 47#define LM95241_REG_RW_REM_FILTER 0x06 48#define LM95241_REG_RW_TRUTHERM 0x07 49#define LM95241_REG_W_ONE_SHOT 0x0F 50#define LM95241_REG_R_LOCAL_TEMPH 0x10 51#define LM95241_REG_R_REMOTE1_TEMPH 0x11 52#define LM95241_REG_R_REMOTE2_TEMPH 0x12 53#define LM95241_REG_R_LOCAL_TEMPL 0x20 54#define LM95241_REG_R_REMOTE1_TEMPL 0x21 55#define LM95241_REG_R_REMOTE2_TEMPL 0x22 56#define LM95241_REG_RW_REMOTE_MODEL 0x30 57 58/* LM95241 specific bitfields */ 59#define CFG_STOP 0x40 60#define CFG_CR0076 0x00 61#define CFG_CR0182 0x10 62#define CFG_CR1000 0x20 63#define CFG_CR2700 0x30 64#define R1MS_SHIFT 0 65#define R2MS_SHIFT 2 66#define R1MS_MASK (0x01 << (R1MS_SHIFT)) 67#define R2MS_MASK (0x01 << (R2MS_SHIFT)) 68#define R1DF_SHIFT 1 69#define R2DF_SHIFT 2 70#define R1DF_MASK (0x01 << (R1DF_SHIFT)) 71#define R2DF_MASK (0x01 << (R2DF_SHIFT)) 72#define R1FE_MASK 0x01 73#define R2FE_MASK 0x05 74#define TT1_SHIFT 0 75#define TT2_SHIFT 4 76#define TT_OFF 0 77#define TT_ON 1 78#define TT_MASK 7 79#define MANUFACTURER_ID 0x01 80#define DEFAULT_REVISION 0xA4 81 82/* Conversions and various macros */ 83#define TEMP_FROM_REG(val_h, val_l) (((val_h) & 0x80 ? (val_h) - 0x100 : \ 84 (val_h)) * 1000 + (val_l) * 1000 / 256) 85 86/* Functions declaration */ 87static void lm95241_init_client(struct i2c_client *client); 88static struct lm95241_data *lm95241_update_device(struct device *dev); 89 90/* Client data (each client gets its own) */ 91struct lm95241_data { 92 struct device *hwmon_dev; 93 struct mutex update_lock; 94 unsigned long last_updated, interval; /* in jiffies */ 95 char valid; /* zero until following fields are valid */ 96 /* registers values */ 97 u8 local_h, local_l; /* local */ 98 u8 remote1_h, remote1_l; /* remote1 */ 99 u8 remote2_h, remote2_l; /* remote2 */ 100 u8 config, model, trutherm; 101}; 102 103/* Sysfs stuff */ 104#define show_temp(value) \ 105static ssize_t show_##value(struct device *dev, \ 106 struct device_attribute *attr, char *buf) \ 107{ \ 108 struct lm95241_data *data = lm95241_update_device(dev); \ 109 snprintf(buf, PAGE_SIZE - 1, "%d\n", \ 110 TEMP_FROM_REG(data->value##_h, data->value##_l)); \ 111 return strlen(buf); \ 112} 113show_temp(local); 114show_temp(remote1); 115show_temp(remote2); 116 117static ssize_t show_interval(struct device *dev, struct device_attribute *attr, 118 char *buf) 119{ 120 struct lm95241_data *data = lm95241_update_device(dev); 121 122 snprintf(buf, PAGE_SIZE - 1, "%lu\n", 1000 * data->interval / HZ); 123 return strlen(buf); 124} 125 126static ssize_t set_interval(struct device *dev, struct device_attribute *attr, 127 const char *buf, size_t count) 128{ 129 struct i2c_client *client = to_i2c_client(dev); 130 struct lm95241_data *data = i2c_get_clientdata(client); 131 132 strict_strtol(buf, 10, &data->interval); 133 data->interval = data->interval * HZ / 1000; 134 135 return count; 136} 137 138#define show_type(flag) \ 139static ssize_t show_type##flag(struct device *dev, \ 140 struct device_attribute *attr, char *buf) \ 141{ \ 142 struct i2c_client *client = to_i2c_client(dev); \ 143 struct lm95241_data *data = i2c_get_clientdata(client); \ 144\ 145 snprintf(buf, PAGE_SIZE - 1, \ 146 data->model & R##flag##MS_MASK ? "1\n" : "2\n"); \ 147 return strlen(buf); \ 148} 149show_type(1); 150show_type(2); 151 152#define show_min(flag) \ 153static ssize_t show_min##flag(struct device *dev, \ 154 struct device_attribute *attr, char *buf) \ 155{ \ 156 struct i2c_client *client = to_i2c_client(dev); \ 157 struct lm95241_data *data = i2c_get_clientdata(client); \ 158\ 159 snprintf(buf, PAGE_SIZE - 1, \ 160 data->config & R##flag##DF_MASK ? \ 161 "-127000\n" : "0\n"); \ 162 return strlen(buf); \ 163} 164show_min(1); 165show_min(2); 166 167#define show_max(flag) \ 168static ssize_t show_max##flag(struct device *dev, \ 169 struct device_attribute *attr, char *buf) \ 170{ \ 171 struct i2c_client *client = to_i2c_client(dev); \ 172 struct lm95241_data *data = i2c_get_clientdata(client); \ 173\ 174 snprintf(buf, PAGE_SIZE - 1, \ 175 data->config & R##flag##DF_MASK ? \ 176 "127000\n" : "255000\n"); \ 177 return strlen(buf); \ 178} 179show_max(1); 180show_max(2); 181 182#define set_type(flag) \ 183static ssize_t set_type##flag(struct device *dev, \ 184 struct device_attribute *attr, \ 185 const char *buf, size_t count) \ 186{ \ 187 struct i2c_client *client = to_i2c_client(dev); \ 188 struct lm95241_data *data = i2c_get_clientdata(client); \ 189\ 190 long val; \ 191 strict_strtol(buf, 10, &val); \ 192\ 193 if ((val == 1) || (val == 2)) { \ 194\ 195 mutex_lock(&data->update_lock); \ 196\ 197 data->trutherm &= ~(TT_MASK << TT##flag##_SHIFT); \ 198 if (val == 1) { \ 199 data->model |= R##flag##MS_MASK; \ 200 data->trutherm |= (TT_ON << TT##flag##_SHIFT); \ 201 } \ 202 else { \ 203 data->model &= ~R##flag##MS_MASK; \ 204 data->trutherm |= (TT_OFF << TT##flag##_SHIFT); \ 205 } \ 206\ 207 data->valid = 0; \ 208\ 209 i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL, \ 210 data->model); \ 211 i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM, \ 212 data->trutherm); \ 213\ 214 mutex_unlock(&data->update_lock); \ 215\ 216 } \ 217 return count; \ 218} 219set_type(1); 220set_type(2); 221 222#define set_min(flag) \ 223static ssize_t set_min##flag(struct device *dev, \ 224 struct device_attribute *devattr, const char *buf, size_t count) \ 225{ \ 226 struct i2c_client *client = to_i2c_client(dev); \ 227 struct lm95241_data *data = i2c_get_clientdata(client); \ 228\ 229 long val; \ 230 strict_strtol(buf, 10, &val); \ 231\ 232 mutex_lock(&data->update_lock); \ 233\ 234 if (val < 0) \ 235 data->config |= R##flag##DF_MASK; \ 236 else \ 237 data->config &= ~R##flag##DF_MASK; \ 238\ 239 data->valid = 0; \ 240\ 241 i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, \ 242 data->config); \ 243\ 244 mutex_unlock(&data->update_lock); \ 245\ 246 return count; \ 247} 248set_min(1); 249set_min(2); 250 251#define set_max(flag) \ 252static ssize_t set_max##flag(struct device *dev, \ 253 struct device_attribute *devattr, const char *buf, size_t count) \ 254{ \ 255 struct i2c_client *client = to_i2c_client(dev); \ 256 struct lm95241_data *data = i2c_get_clientdata(client); \ 257\ 258 long val; \ 259 strict_strtol(buf, 10, &val); \ 260\ 261 mutex_lock(&data->update_lock); \ 262\ 263 if (val <= 127000) \ 264 data->config |= R##flag##DF_MASK; \ 265 else \ 266 data->config &= ~R##flag##DF_MASK; \ 267\ 268 data->valid = 0; \ 269\ 270 i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, \ 271 data->config); \ 272\ 273 mutex_unlock(&data->update_lock); \ 274\ 275 return count; \ 276} 277set_max(1); 278set_max(2); 279 280static DEVICE_ATTR(temp1_input, S_IRUGO, show_local, NULL); 281static DEVICE_ATTR(temp2_input, S_IRUGO, show_remote1, NULL); 282static DEVICE_ATTR(temp3_input, S_IRUGO, show_remote2, NULL); 283static DEVICE_ATTR(temp2_type, S_IWUSR | S_IRUGO, show_type1, set_type1); 284static DEVICE_ATTR(temp3_type, S_IWUSR | S_IRUGO, show_type2, set_type2); 285static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_min1, set_min1); 286static DEVICE_ATTR(temp3_min, S_IWUSR | S_IRUGO, show_min2, set_min2); 287static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_max1, set_max1); 288static DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_max2, set_max2); 289static DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO, show_interval, 290 set_interval); 291 292static struct attribute *lm95241_attributes[] = { 293 &dev_attr_temp1_input.attr, 294 &dev_attr_temp2_input.attr, 295 &dev_attr_temp3_input.attr, 296 &dev_attr_temp2_type.attr, 297 &dev_attr_temp3_type.attr, 298 &dev_attr_temp2_min.attr, 299 &dev_attr_temp3_min.attr, 300 &dev_attr_temp2_max.attr, 301 &dev_attr_temp3_max.attr, 302 &dev_attr_update_interval.attr, 303 NULL 304}; 305 306static const struct attribute_group lm95241_group = { 307 .attrs = lm95241_attributes, 308}; 309 310/* Return 0 if detection is successful, -ENODEV otherwise */ 311static int lm95241_detect(struct i2c_client *new_client, 312 struct i2c_board_info *info) 313{ 314 struct i2c_adapter *adapter = new_client->adapter; 315 int address = new_client->addr; 316 const char *name; 317 318 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 319 return -ENODEV; 320 321 if ((i2c_smbus_read_byte_data(new_client, LM95241_REG_R_MAN_ID) 322 == MANUFACTURER_ID) 323 && (i2c_smbus_read_byte_data(new_client, LM95241_REG_R_CHIP_ID) 324 >= DEFAULT_REVISION)) { 325 name = "lm95241"; 326 } else { 327 dev_dbg(&adapter->dev, "LM95241 detection failed at 0x%02x\n", 328 address); 329 return -ENODEV; 330 } 331 332 /* Fill the i2c board info */ 333 strlcpy(info->type, name, I2C_NAME_SIZE); 334 return 0; 335} 336 337static int lm95241_probe(struct i2c_client *new_client, 338 const struct i2c_device_id *id) 339{ 340 struct lm95241_data *data; 341 int err; 342 343 data = kzalloc(sizeof(struct lm95241_data), GFP_KERNEL); 344 if (!data) { 345 err = -ENOMEM; 346 goto exit; 347 } 348 349 i2c_set_clientdata(new_client, data); 350 mutex_init(&data->update_lock); 351 352 /* Initialize the LM95241 chip */ 353 lm95241_init_client(new_client); 354 355 /* Register sysfs hooks */ 356 err = sysfs_create_group(&new_client->dev.kobj, &lm95241_group); 357 if (err) 358 goto exit_free; 359 360 data->hwmon_dev = hwmon_device_register(&new_client->dev); 361 if (IS_ERR(data->hwmon_dev)) { 362 err = PTR_ERR(data->hwmon_dev); 363 goto exit_remove_files; 364 } 365 366 return 0; 367 368exit_remove_files: 369 sysfs_remove_group(&new_client->dev.kobj, &lm95241_group); 370exit_free: 371 kfree(data); 372exit: 373 return err; 374} 375 376static void lm95241_init_client(struct i2c_client *client) 377{ 378 struct lm95241_data *data = i2c_get_clientdata(client); 379 380 data->interval = HZ; /* 1 sec default */ 381 data->valid = 0; 382 data->config = CFG_CR0076; 383 data->model = 0; 384 data->trutherm = (TT_OFF << TT1_SHIFT) | (TT_OFF << TT2_SHIFT); 385 386 i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, 387 data->config); 388 i2c_smbus_write_byte_data(client, LM95241_REG_RW_REM_FILTER, 389 R1FE_MASK | R2FE_MASK); 390 i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM, 391 data->trutherm); 392 i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL, 393 data->model); 394} 395 396static int lm95241_remove(struct i2c_client *client) 397{ 398 struct lm95241_data *data = i2c_get_clientdata(client); 399 400 hwmon_device_unregister(data->hwmon_dev); 401 sysfs_remove_group(&client->dev.kobj, &lm95241_group); 402 403 kfree(data); 404 return 0; 405} 406 407static struct lm95241_data *lm95241_update_device(struct device *dev) 408{ 409 struct i2c_client *client = to_i2c_client(dev); 410 struct lm95241_data *data = i2c_get_clientdata(client); 411 412 mutex_lock(&data->update_lock); 413 414 if (time_after(jiffies, data->last_updated + data->interval) || 415 !data->valid) { 416 dev_dbg(&client->dev, "Updating lm95241 data.\n"); 417 data->local_h = 418 i2c_smbus_read_byte_data(client, 419 LM95241_REG_R_LOCAL_TEMPH); 420 data->local_l = 421 i2c_smbus_read_byte_data(client, 422 LM95241_REG_R_LOCAL_TEMPL); 423 data->remote1_h = 424 i2c_smbus_read_byte_data(client, 425 LM95241_REG_R_REMOTE1_TEMPH); 426 data->remote1_l = 427 i2c_smbus_read_byte_data(client, 428 LM95241_REG_R_REMOTE1_TEMPL); 429 data->remote2_h = 430 i2c_smbus_read_byte_data(client, 431 LM95241_REG_R_REMOTE2_TEMPH); 432 data->remote2_l = 433 i2c_smbus_read_byte_data(client, 434 LM95241_REG_R_REMOTE2_TEMPL); 435 data->last_updated = jiffies; 436 data->valid = 1; 437 } 438 439 mutex_unlock(&data->update_lock); 440 441 return data; 442} 443 444/* Driver data (common to all clients) */ 445static const struct i2c_device_id lm95241_id[] = { 446 { "lm95241", 0 }, 447 { } 448}; 449MODULE_DEVICE_TABLE(i2c, lm95241_id); 450 451static struct i2c_driver lm95241_driver = { 452 .class = I2C_CLASS_HWMON, 453 .driver = { 454 .name = "lm95241", 455 }, 456 .probe = lm95241_probe, 457 .remove = lm95241_remove, 458 .id_table = lm95241_id, 459 .detect = lm95241_detect, 460 .address_list = normal_i2c, 461}; 462 463static int __init sensors_lm95241_init(void) 464{ 465 return i2c_add_driver(&lm95241_driver); 466} 467 468static void __exit sensors_lm95241_exit(void) 469{ 470 i2c_del_driver(&lm95241_driver); 471} 472 473MODULE_AUTHOR("Davide Rizzo <elpa-rizzo@gmail.com>"); 474MODULE_DESCRIPTION("LM95241 sensor driver"); 475MODULE_LICENSE("GPL"); 476 477module_init(sensors_lm95241_init); 478module_exit(sensors_lm95241_exit); 479