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 39 static 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 */ 87 static void lm95241_init_client(struct i2c_client *client); 88 static struct lm95241_data *lm95241_update_device(struct device *dev); 89 90 /* Client data (each client gets its own) */ 91 struct 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) \ 105 static 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 } 113 show_temp(local); 114 show_temp(remote1); 115 show_temp(remote2); 116 117 static 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 } 125 126 static 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 unsigned long val; 132 133 if (strict_strtoul(buf, 10, &val) < 0) 134 return -EINVAL; 135 136 data->interval = val * HZ / 1000; 137 138 return count; 139 } 140 141 #define show_type(flag) \ 142 static ssize_t show_type##flag(struct device *dev, \ 143 struct device_attribute *attr, char *buf) \ 144 { \ 145 struct i2c_client *client = to_i2c_client(dev); \ 146 struct lm95241_data *data = i2c_get_clientdata(client); \ 147 \ 148 snprintf(buf, PAGE_SIZE - 1, \ 149 data->model & R##flag##MS_MASK ? "1\n" : "2\n"); \ 150 return strlen(buf); \ 151 } 152 show_type(1); 153 show_type(2); 154 155 #define show_min(flag) \ 156 static ssize_t show_min##flag(struct device *dev, \ 157 struct device_attribute *attr, char *buf) \ 158 { \ 159 struct i2c_client *client = to_i2c_client(dev); \ 160 struct lm95241_data *data = i2c_get_clientdata(client); \ 161 \ 162 snprintf(buf, PAGE_SIZE - 1, \ 163 data->config & R##flag##DF_MASK ? \ 164 "-127000\n" : "0\n"); \ 165 return strlen(buf); \ 166 } 167 show_min(1); 168 show_min(2); 169 170 #define show_max(flag) \ 171 static ssize_t show_max##flag(struct device *dev, \ 172 struct device_attribute *attr, char *buf) \ 173 { \ 174 struct i2c_client *client = to_i2c_client(dev); \ 175 struct lm95241_data *data = i2c_get_clientdata(client); \ 176 \ 177 snprintf(buf, PAGE_SIZE - 1, \ 178 data->config & R##flag##DF_MASK ? \ 179 "127000\n" : "255000\n"); \ 180 return strlen(buf); \ 181 } 182 show_max(1); 183 show_max(2); 184 185 #define set_type(flag) \ 186 static ssize_t set_type##flag(struct device *dev, \ 187 struct device_attribute *attr, \ 188 const char *buf, size_t count) \ 189 { \ 190 struct i2c_client *client = to_i2c_client(dev); \ 191 struct lm95241_data *data = i2c_get_clientdata(client); \ 192 \ 193 long val; \ 194 \ 195 if (strict_strtol(buf, 10, &val) < 0) \ 196 return -EINVAL; \ 197 \ 198 if ((val == 1) || (val == 2)) { \ 199 \ 200 mutex_lock(&data->update_lock); \ 201 \ 202 data->trutherm &= ~(TT_MASK << TT##flag##_SHIFT); \ 203 if (val == 1) { \ 204 data->model |= R##flag##MS_MASK; \ 205 data->trutherm |= (TT_ON << TT##flag##_SHIFT); \ 206 } \ 207 else { \ 208 data->model &= ~R##flag##MS_MASK; \ 209 data->trutherm |= (TT_OFF << TT##flag##_SHIFT); \ 210 } \ 211 \ 212 data->valid = 0; \ 213 \ 214 i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL, \ 215 data->model); \ 216 i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM, \ 217 data->trutherm); \ 218 \ 219 mutex_unlock(&data->update_lock); \ 220 \ 221 } \ 222 return count; \ 223 } 224 set_type(1); 225 set_type(2); 226 227 #define set_min(flag) \ 228 static ssize_t set_min##flag(struct device *dev, \ 229 struct device_attribute *devattr, const char *buf, size_t count) \ 230 { \ 231 struct i2c_client *client = to_i2c_client(dev); \ 232 struct lm95241_data *data = i2c_get_clientdata(client); \ 233 \ 234 long val; \ 235 \ 236 if (strict_strtol(buf, 10, &val) < 0) \ 237 return -EINVAL;\ 238 \ 239 mutex_lock(&data->update_lock); \ 240 \ 241 if (val < 0) \ 242 data->config |= R##flag##DF_MASK; \ 243 else \ 244 data->config &= ~R##flag##DF_MASK; \ 245 \ 246 data->valid = 0; \ 247 \ 248 i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, \ 249 data->config); \ 250 \ 251 mutex_unlock(&data->update_lock); \ 252 \ 253 return count; \ 254 } 255 set_min(1); 256 set_min(2); 257 258 #define set_max(flag) \ 259 static ssize_t set_max##flag(struct device *dev, \ 260 struct device_attribute *devattr, const char *buf, size_t count) \ 261 { \ 262 struct i2c_client *client = to_i2c_client(dev); \ 263 struct lm95241_data *data = i2c_get_clientdata(client); \ 264 \ 265 long val; \ 266 \ 267 if (strict_strtol(buf, 10, &val) < 0) \ 268 return -EINVAL; \ 269 \ 270 mutex_lock(&data->update_lock); \ 271 \ 272 if (val <= 127000) \ 273 data->config |= R##flag##DF_MASK; \ 274 else \ 275 data->config &= ~R##flag##DF_MASK; \ 276 \ 277 data->valid = 0; \ 278 \ 279 i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, \ 280 data->config); \ 281 \ 282 mutex_unlock(&data->update_lock); \ 283 \ 284 return count; \ 285 } 286 set_max(1); 287 set_max(2); 288 289 static DEVICE_ATTR(temp1_input, S_IRUGO, show_local, NULL); 290 static DEVICE_ATTR(temp2_input, S_IRUGO, show_remote1, NULL); 291 static DEVICE_ATTR(temp3_input, S_IRUGO, show_remote2, NULL); 292 static DEVICE_ATTR(temp2_type, S_IWUSR | S_IRUGO, show_type1, set_type1); 293 static DEVICE_ATTR(temp3_type, S_IWUSR | S_IRUGO, show_type2, set_type2); 294 static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_min1, set_min1); 295 static DEVICE_ATTR(temp3_min, S_IWUSR | S_IRUGO, show_min2, set_min2); 296 static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_max1, set_max1); 297 static DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_max2, set_max2); 298 static DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO, show_interval, 299 set_interval); 300 301 static struct attribute *lm95241_attributes[] = { 302 &dev_attr_temp1_input.attr, 303 &dev_attr_temp2_input.attr, 304 &dev_attr_temp3_input.attr, 305 &dev_attr_temp2_type.attr, 306 &dev_attr_temp3_type.attr, 307 &dev_attr_temp2_min.attr, 308 &dev_attr_temp3_min.attr, 309 &dev_attr_temp2_max.attr, 310 &dev_attr_temp3_max.attr, 311 &dev_attr_update_interval.attr, 312 NULL 313 }; 314 315 static const struct attribute_group lm95241_group = { 316 .attrs = lm95241_attributes, 317 }; 318 319 /* Return 0 if detection is successful, -ENODEV otherwise */ 320 static int lm95241_detect(struct i2c_client *new_client, 321 struct i2c_board_info *info) 322 { 323 struct i2c_adapter *adapter = new_client->adapter; 324 int address = new_client->addr; 325 const char *name; 326 327 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 328 return -ENODEV; 329 330 if ((i2c_smbus_read_byte_data(new_client, LM95241_REG_R_MAN_ID) 331 == MANUFACTURER_ID) 332 && (i2c_smbus_read_byte_data(new_client, LM95241_REG_R_CHIP_ID) 333 >= DEFAULT_REVISION)) { 334 name = "lm95241"; 335 } else { 336 dev_dbg(&adapter->dev, "LM95241 detection failed at 0x%02x\n", 337 address); 338 return -ENODEV; 339 } 340 341 /* Fill the i2c board info */ 342 strlcpy(info->type, name, I2C_NAME_SIZE); 343 return 0; 344 } 345 346 static int lm95241_probe(struct i2c_client *new_client, 347 const struct i2c_device_id *id) 348 { 349 struct lm95241_data *data; 350 int err; 351 352 data = kzalloc(sizeof(struct lm95241_data), GFP_KERNEL); 353 if (!data) { 354 err = -ENOMEM; 355 goto exit; 356 } 357 358 i2c_set_clientdata(new_client, data); 359 mutex_init(&data->update_lock); 360 361 /* Initialize the LM95241 chip */ 362 lm95241_init_client(new_client); 363 364 /* Register sysfs hooks */ 365 err = sysfs_create_group(&new_client->dev.kobj, &lm95241_group); 366 if (err) 367 goto exit_free; 368 369 data->hwmon_dev = hwmon_device_register(&new_client->dev); 370 if (IS_ERR(data->hwmon_dev)) { 371 err = PTR_ERR(data->hwmon_dev); 372 goto exit_remove_files; 373 } 374 375 return 0; 376 377 exit_remove_files: 378 sysfs_remove_group(&new_client->dev.kobj, &lm95241_group); 379 exit_free: 380 kfree(data); 381 exit: 382 return err; 383 } 384 385 static void lm95241_init_client(struct i2c_client *client) 386 { 387 struct lm95241_data *data = i2c_get_clientdata(client); 388 389 data->interval = HZ; /* 1 sec default */ 390 data->valid = 0; 391 data->config = CFG_CR0076; 392 data->model = 0; 393 data->trutherm = (TT_OFF << TT1_SHIFT) | (TT_OFF << TT2_SHIFT); 394 395 i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, 396 data->config); 397 i2c_smbus_write_byte_data(client, LM95241_REG_RW_REM_FILTER, 398 R1FE_MASK | R2FE_MASK); 399 i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM, 400 data->trutherm); 401 i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL, 402 data->model); 403 } 404 405 static int lm95241_remove(struct i2c_client *client) 406 { 407 struct lm95241_data *data = i2c_get_clientdata(client); 408 409 hwmon_device_unregister(data->hwmon_dev); 410 sysfs_remove_group(&client->dev.kobj, &lm95241_group); 411 412 kfree(data); 413 return 0; 414 } 415 416 static struct lm95241_data *lm95241_update_device(struct device *dev) 417 { 418 struct i2c_client *client = to_i2c_client(dev); 419 struct lm95241_data *data = i2c_get_clientdata(client); 420 421 mutex_lock(&data->update_lock); 422 423 if (time_after(jiffies, data->last_updated + data->interval) || 424 !data->valid) { 425 dev_dbg(&client->dev, "Updating lm95241 data.\n"); 426 data->local_h = 427 i2c_smbus_read_byte_data(client, 428 LM95241_REG_R_LOCAL_TEMPH); 429 data->local_l = 430 i2c_smbus_read_byte_data(client, 431 LM95241_REG_R_LOCAL_TEMPL); 432 data->remote1_h = 433 i2c_smbus_read_byte_data(client, 434 LM95241_REG_R_REMOTE1_TEMPH); 435 data->remote1_l = 436 i2c_smbus_read_byte_data(client, 437 LM95241_REG_R_REMOTE1_TEMPL); 438 data->remote2_h = 439 i2c_smbus_read_byte_data(client, 440 LM95241_REG_R_REMOTE2_TEMPH); 441 data->remote2_l = 442 i2c_smbus_read_byte_data(client, 443 LM95241_REG_R_REMOTE2_TEMPL); 444 data->last_updated = jiffies; 445 data->valid = 1; 446 } 447 448 mutex_unlock(&data->update_lock); 449 450 return data; 451 } 452 453 /* Driver data (common to all clients) */ 454 static const struct i2c_device_id lm95241_id[] = { 455 { "lm95241", 0 }, 456 { } 457 }; 458 MODULE_DEVICE_TABLE(i2c, lm95241_id); 459 460 static struct i2c_driver lm95241_driver = { 461 .class = I2C_CLASS_HWMON, 462 .driver = { 463 .name = "lm95241", 464 }, 465 .probe = lm95241_probe, 466 .remove = lm95241_remove, 467 .id_table = lm95241_id, 468 .detect = lm95241_detect, 469 .address_list = normal_i2c, 470 }; 471 472 static int __init sensors_lm95241_init(void) 473 { 474 return i2c_add_driver(&lm95241_driver); 475 } 476 477 static void __exit sensors_lm95241_exit(void) 478 { 479 i2c_del_driver(&lm95241_driver); 480 } 481 482 MODULE_AUTHOR("Davide Rizzo <elpa-rizzo@gmail.com>"); 483 MODULE_DESCRIPTION("LM95241 sensor driver"); 484 MODULE_LICENSE("GPL"); 485 486 module_init(sensors_lm95241_init); 487 module_exit(sensors_lm95241_exit); 488