1 /* 2 * lm90.c - Part of lm_sensors, Linux kernel modules for hardware 3 * monitoring 4 * Copyright (C) 2003-2005 Jean Delvare <khali@linux-fr.org> 5 * 6 * Based on the lm83 driver. The LM90 is a sensor chip made by National 7 * Semiconductor. It reports up to two temperatures (its own plus up to 8 * one external one) with a 0.125 deg resolution (1 deg for local 9 * temperature) and a 3-4 deg accuracy. Complete datasheet can be 10 * obtained from National's website at: 11 * http://www.national.com/pf/LM/LM90.html 12 * 13 * This driver also supports the LM89 and LM99, two other sensor chips 14 * made by National Semiconductor. Both have an increased remote 15 * temperature measurement accuracy (1 degree), and the LM99 16 * additionally shifts remote temperatures (measured and limits) by 16 17 * degrees, which allows for higher temperatures measurement. The 18 * driver doesn't handle it since it can be done easily in user-space. 19 * Complete datasheets can be obtained from National's website at: 20 * http://www.national.com/pf/LM/LM89.html 21 * http://www.national.com/pf/LM/LM99.html 22 * Note that there is no way to differentiate between both chips. 23 * 24 * This driver also supports the LM86, another sensor chip made by 25 * National Semiconductor. It is exactly similar to the LM90 except it 26 * has a higher accuracy. 27 * Complete datasheet can be obtained from National's website at: 28 * http://www.national.com/pf/LM/LM86.html 29 * 30 * This driver also supports the ADM1032, a sensor chip made by Analog 31 * Devices. That chip is similar to the LM90, with a few differences 32 * that are not handled by this driver. Complete datasheet can be 33 * obtained from Analog's website at: 34 * http://www.analog.com/en/prod/0,2877,ADM1032,00.html 35 * Among others, it has a higher accuracy than the LM90, much like the 36 * LM86 does. 37 * 38 * This driver also supports the MAX6657, MAX6658 and MAX6659 sensor 39 * chips made by Maxim. These chips are similar to the LM86. Complete 40 * datasheet can be obtained at Maxim's website at: 41 * http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2578 42 * Note that there is no easy way to differentiate between the three 43 * variants. The extra address and features of the MAX6659 are not 44 * supported by this driver. 45 * 46 * This driver also supports the ADT7461 chip from Analog Devices but 47 * only in its "compatability mode". If an ADT7461 chip is found but 48 * is configured in non-compatible mode (where its temperature 49 * register values are decoded differently) it is ignored by this 50 * driver. Complete datasheet can be obtained from Analog's website 51 * at: 52 * http://www.analog.com/en/prod/0,2877,ADT7461,00.html 53 * 54 * Since the LM90 was the first chipset supported by this driver, most 55 * comments will refer to this chipset, but are actually general and 56 * concern all supported chipsets, unless mentioned otherwise. 57 * 58 * This program is free software; you can redistribute it and/or modify 59 * it under the terms of the GNU General Public License as published by 60 * the Free Software Foundation; either version 2 of the License, or 61 * (at your option) any later version. 62 * 63 * This program is distributed in the hope that it will be useful, 64 * but WITHOUT ANY WARRANTY; without even the implied warranty of 65 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 66 * GNU General Public License for more details. 67 * 68 * You should have received a copy of the GNU General Public License 69 * along with this program; if not, write to the Free Software 70 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 71 */ 72 73 #include <linux/module.h> 74 #include <linux/init.h> 75 #include <linux/slab.h> 76 #include <linux/jiffies.h> 77 #include <linux/i2c.h> 78 #include <linux/hwmon-sysfs.h> 79 #include <linux/hwmon.h> 80 #include <linux/err.h> 81 #include <linux/mutex.h> 82 83 /* 84 * Addresses to scan 85 * Address is fully defined internally and cannot be changed except for 86 * MAX6659. 87 * LM86, LM89, LM90, LM99, ADM1032, ADM1032-1, ADT7461, MAX6657 and MAX6658 88 * have address 0x4c. 89 * ADM1032-2, ADT7461-2, LM89-1, and LM99-1 have address 0x4d. 90 * MAX6659 can have address 0x4c, 0x4d or 0x4e (unsupported). 91 */ 92 93 static unsigned short normal_i2c[] = { 0x4c, 0x4d, I2C_CLIENT_END }; 94 95 /* 96 * Insmod parameters 97 */ 98 99 I2C_CLIENT_INSMOD_6(lm90, adm1032, lm99, lm86, max6657, adt7461); 100 101 /* 102 * The LM90 registers 103 */ 104 105 #define LM90_REG_R_MAN_ID 0xFE 106 #define LM90_REG_R_CHIP_ID 0xFF 107 #define LM90_REG_R_CONFIG1 0x03 108 #define LM90_REG_W_CONFIG1 0x09 109 #define LM90_REG_R_CONFIG2 0xBF 110 #define LM90_REG_W_CONFIG2 0xBF 111 #define LM90_REG_R_CONVRATE 0x04 112 #define LM90_REG_W_CONVRATE 0x0A 113 #define LM90_REG_R_STATUS 0x02 114 #define LM90_REG_R_LOCAL_TEMP 0x00 115 #define LM90_REG_R_LOCAL_HIGH 0x05 116 #define LM90_REG_W_LOCAL_HIGH 0x0B 117 #define LM90_REG_R_LOCAL_LOW 0x06 118 #define LM90_REG_W_LOCAL_LOW 0x0C 119 #define LM90_REG_R_LOCAL_CRIT 0x20 120 #define LM90_REG_W_LOCAL_CRIT 0x20 121 #define LM90_REG_R_REMOTE_TEMPH 0x01 122 #define LM90_REG_R_REMOTE_TEMPL 0x10 123 #define LM90_REG_R_REMOTE_OFFSH 0x11 124 #define LM90_REG_W_REMOTE_OFFSH 0x11 125 #define LM90_REG_R_REMOTE_OFFSL 0x12 126 #define LM90_REG_W_REMOTE_OFFSL 0x12 127 #define LM90_REG_R_REMOTE_HIGHH 0x07 128 #define LM90_REG_W_REMOTE_HIGHH 0x0D 129 #define LM90_REG_R_REMOTE_HIGHL 0x13 130 #define LM90_REG_W_REMOTE_HIGHL 0x13 131 #define LM90_REG_R_REMOTE_LOWH 0x08 132 #define LM90_REG_W_REMOTE_LOWH 0x0E 133 #define LM90_REG_R_REMOTE_LOWL 0x14 134 #define LM90_REG_W_REMOTE_LOWL 0x14 135 #define LM90_REG_R_REMOTE_CRIT 0x19 136 #define LM90_REG_W_REMOTE_CRIT 0x19 137 #define LM90_REG_R_TCRIT_HYST 0x21 138 #define LM90_REG_W_TCRIT_HYST 0x21 139 140 /* 141 * Conversions and various macros 142 * For local temperatures and limits, critical limits and the hysteresis 143 * value, the LM90 uses signed 8-bit values with LSB = 1 degree Celsius. 144 * For remote temperatures and limits, it uses signed 11-bit values with 145 * LSB = 0.125 degree Celsius, left-justified in 16-bit registers. 146 */ 147 148 #define TEMP1_FROM_REG(val) ((val) * 1000) 149 #define TEMP1_TO_REG(val) ((val) <= -128000 ? -128 : \ 150 (val) >= 127000 ? 127 : \ 151 (val) < 0 ? ((val) - 500) / 1000 : \ 152 ((val) + 500) / 1000) 153 #define TEMP2_FROM_REG(val) ((val) / 32 * 125) 154 #define TEMP2_TO_REG(val) ((val) <= -128000 ? 0x8000 : \ 155 (val) >= 127875 ? 0x7FE0 : \ 156 (val) < 0 ? ((val) - 62) / 125 * 32 : \ 157 ((val) + 62) / 125 * 32) 158 #define HYST_TO_REG(val) ((val) <= 0 ? 0 : (val) >= 30500 ? 31 : \ 159 ((val) + 500) / 1000) 160 161 /* 162 * ADT7461 is almost identical to LM90 except that attempts to write 163 * values that are outside the range 0 < temp < 127 are treated as 164 * the boundary value. 165 */ 166 167 #define TEMP1_TO_REG_ADT7461(val) ((val) <= 0 ? 0 : \ 168 (val) >= 127000 ? 127 : \ 169 ((val) + 500) / 1000) 170 #define TEMP2_TO_REG_ADT7461(val) ((val) <= 0 ? 0 : \ 171 (val) >= 127750 ? 0x7FC0 : \ 172 ((val) + 125) / 250 * 64) 173 174 /* 175 * Functions declaration 176 */ 177 178 static int lm90_attach_adapter(struct i2c_adapter *adapter); 179 static int lm90_detect(struct i2c_adapter *adapter, int address, 180 int kind); 181 static void lm90_init_client(struct i2c_client *client); 182 static int lm90_detach_client(struct i2c_client *client); 183 static struct lm90_data *lm90_update_device(struct device *dev); 184 185 /* 186 * Driver data (common to all clients) 187 */ 188 189 static struct i2c_driver lm90_driver = { 190 .driver = { 191 .name = "lm90", 192 }, 193 .id = I2C_DRIVERID_LM90, 194 .attach_adapter = lm90_attach_adapter, 195 .detach_client = lm90_detach_client, 196 }; 197 198 /* 199 * Client data (each client gets its own) 200 */ 201 202 struct lm90_data { 203 struct i2c_client client; 204 struct class_device *class_dev; 205 struct mutex update_lock; 206 char valid; /* zero until following fields are valid */ 207 unsigned long last_updated; /* in jiffies */ 208 int kind; 209 210 /* registers values */ 211 s8 temp8[5]; /* 0: local input 212 1: local low limit 213 2: local high limit 214 3: local critical limit 215 4: remote critical limit */ 216 s16 temp11[3]; /* 0: remote input 217 1: remote low limit 218 2: remote high limit */ 219 u8 temp_hyst; 220 u8 alarms; /* bitvector */ 221 }; 222 223 /* 224 * Sysfs stuff 225 */ 226 227 static ssize_t show_temp8(struct device *dev, struct device_attribute *devattr, 228 char *buf) 229 { 230 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 231 struct lm90_data *data = lm90_update_device(dev); 232 return sprintf(buf, "%d\n", TEMP1_FROM_REG(data->temp8[attr->index])); 233 } 234 235 static ssize_t set_temp8(struct device *dev, struct device_attribute *devattr, 236 const char *buf, size_t count) 237 { 238 static const u8 reg[4] = { 239 LM90_REG_W_LOCAL_LOW, 240 LM90_REG_W_LOCAL_HIGH, 241 LM90_REG_W_LOCAL_CRIT, 242 LM90_REG_W_REMOTE_CRIT, 243 }; 244 245 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 246 struct i2c_client *client = to_i2c_client(dev); 247 struct lm90_data *data = i2c_get_clientdata(client); 248 long val = simple_strtol(buf, NULL, 10); 249 int nr = attr->index; 250 251 mutex_lock(&data->update_lock); 252 if (data->kind == adt7461) 253 data->temp8[nr] = TEMP1_TO_REG_ADT7461(val); 254 else 255 data->temp8[nr] = TEMP1_TO_REG(val); 256 i2c_smbus_write_byte_data(client, reg[nr - 1], data->temp8[nr]); 257 mutex_unlock(&data->update_lock); 258 return count; 259 } 260 261 static ssize_t show_temp11(struct device *dev, struct device_attribute *devattr, 262 char *buf) 263 { 264 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 265 struct lm90_data *data = lm90_update_device(dev); 266 return sprintf(buf, "%d\n", TEMP2_FROM_REG(data->temp11[attr->index])); 267 } 268 269 static ssize_t set_temp11(struct device *dev, struct device_attribute *devattr, 270 const char *buf, size_t count) 271 { 272 static const u8 reg[4] = { 273 LM90_REG_W_REMOTE_LOWH, 274 LM90_REG_W_REMOTE_LOWL, 275 LM90_REG_W_REMOTE_HIGHH, 276 LM90_REG_W_REMOTE_HIGHL, 277 }; 278 279 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 280 struct i2c_client *client = to_i2c_client(dev); 281 struct lm90_data *data = i2c_get_clientdata(client); 282 long val = simple_strtol(buf, NULL, 10); 283 int nr = attr->index; 284 285 mutex_lock(&data->update_lock); 286 if (data->kind == adt7461) 287 data->temp11[nr] = TEMP2_TO_REG_ADT7461(val); 288 else 289 data->temp11[nr] = TEMP2_TO_REG(val); 290 i2c_smbus_write_byte_data(client, reg[(nr - 1) * 2], 291 data->temp11[nr] >> 8); 292 i2c_smbus_write_byte_data(client, reg[(nr - 1) * 2 + 1], 293 data->temp11[nr] & 0xff); 294 mutex_unlock(&data->update_lock); 295 return count; 296 } 297 298 static ssize_t show_temphyst(struct device *dev, struct device_attribute *devattr, 299 char *buf) 300 { 301 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 302 struct lm90_data *data = lm90_update_device(dev); 303 return sprintf(buf, "%d\n", TEMP1_FROM_REG(data->temp8[attr->index]) 304 - TEMP1_FROM_REG(data->temp_hyst)); 305 } 306 307 static ssize_t set_temphyst(struct device *dev, struct device_attribute *dummy, 308 const char *buf, size_t count) 309 { 310 struct i2c_client *client = to_i2c_client(dev); 311 struct lm90_data *data = i2c_get_clientdata(client); 312 long val = simple_strtol(buf, NULL, 10); 313 long hyst; 314 315 mutex_lock(&data->update_lock); 316 hyst = TEMP1_FROM_REG(data->temp8[3]) - val; 317 i2c_smbus_write_byte_data(client, LM90_REG_W_TCRIT_HYST, 318 HYST_TO_REG(hyst)); 319 mutex_unlock(&data->update_lock); 320 return count; 321 } 322 323 static ssize_t show_alarms(struct device *dev, struct device_attribute *dummy, 324 char *buf) 325 { 326 struct lm90_data *data = lm90_update_device(dev); 327 return sprintf(buf, "%d\n", data->alarms); 328 } 329 330 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp8, NULL, 0); 331 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp11, NULL, 0); 332 static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp8, 333 set_temp8, 1); 334 static SENSOR_DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp11, 335 set_temp11, 1); 336 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp8, 337 set_temp8, 2); 338 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp11, 339 set_temp11, 2); 340 static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp8, 341 set_temp8, 3); 342 static SENSOR_DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp8, 343 set_temp8, 4); 344 static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_temphyst, 345 set_temphyst, 3); 346 static SENSOR_DEVICE_ATTR(temp2_crit_hyst, S_IRUGO, show_temphyst, NULL, 4); 347 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL); 348 349 /* pec used for ADM1032 only */ 350 static ssize_t show_pec(struct device *dev, struct device_attribute *dummy, 351 char *buf) 352 { 353 struct i2c_client *client = to_i2c_client(dev); 354 return sprintf(buf, "%d\n", !!(client->flags & I2C_CLIENT_PEC)); 355 } 356 357 static ssize_t set_pec(struct device *dev, struct device_attribute *dummy, 358 const char *buf, size_t count) 359 { 360 struct i2c_client *client = to_i2c_client(dev); 361 long val = simple_strtol(buf, NULL, 10); 362 363 switch (val) { 364 case 0: 365 client->flags &= ~I2C_CLIENT_PEC; 366 break; 367 case 1: 368 client->flags |= I2C_CLIENT_PEC; 369 break; 370 default: 371 return -EINVAL; 372 } 373 374 return count; 375 } 376 377 static DEVICE_ATTR(pec, S_IWUSR | S_IRUGO, show_pec, set_pec); 378 379 /* 380 * Real code 381 */ 382 383 /* The ADM1032 supports PEC but not on write byte transactions, so we need 384 to explicitely ask for a transaction without PEC. */ 385 static inline s32 adm1032_write_byte(struct i2c_client *client, u8 value) 386 { 387 return i2c_smbus_xfer(client->adapter, client->addr, 388 client->flags & ~I2C_CLIENT_PEC, 389 I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); 390 } 391 392 /* It is assumed that client->update_lock is held (unless we are in 393 detection or initialization steps). This matters when PEC is enabled, 394 because we don't want the address pointer to change between the write 395 byte and the read byte transactions. */ 396 static int lm90_read_reg(struct i2c_client* client, u8 reg, u8 *value) 397 { 398 int err; 399 400 if (client->flags & I2C_CLIENT_PEC) { 401 err = adm1032_write_byte(client, reg); 402 if (err >= 0) 403 err = i2c_smbus_read_byte(client); 404 } else 405 err = i2c_smbus_read_byte_data(client, reg); 406 407 if (err < 0) { 408 dev_warn(&client->dev, "Register %#02x read failed (%d)\n", 409 reg, err); 410 return err; 411 } 412 *value = err; 413 414 return 0; 415 } 416 417 static int lm90_attach_adapter(struct i2c_adapter *adapter) 418 { 419 if (!(adapter->class & I2C_CLASS_HWMON)) 420 return 0; 421 return i2c_probe(adapter, &addr_data, lm90_detect); 422 } 423 424 /* 425 * The following function does more than just detection. If detection 426 * succeeds, it also registers the new chip. 427 */ 428 static int lm90_detect(struct i2c_adapter *adapter, int address, int kind) 429 { 430 struct i2c_client *new_client; 431 struct lm90_data *data; 432 int err = 0; 433 const char *name = ""; 434 435 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 436 goto exit; 437 438 if (!(data = kzalloc(sizeof(struct lm90_data), GFP_KERNEL))) { 439 err = -ENOMEM; 440 goto exit; 441 } 442 443 /* The common I2C client data is placed right before the 444 LM90-specific data. */ 445 new_client = &data->client; 446 i2c_set_clientdata(new_client, data); 447 new_client->addr = address; 448 new_client->adapter = adapter; 449 new_client->driver = &lm90_driver; 450 new_client->flags = 0; 451 452 /* 453 * Now we do the remaining detection. A negative kind means that 454 * the driver was loaded with no force parameter (default), so we 455 * must both detect and identify the chip. A zero kind means that 456 * the driver was loaded with the force parameter, the detection 457 * step shall be skipped. A positive kind means that the driver 458 * was loaded with the force parameter and a given kind of chip is 459 * requested, so both the detection and the identification steps 460 * are skipped. 461 */ 462 463 /* Default to an LM90 if forced */ 464 if (kind == 0) 465 kind = lm90; 466 467 if (kind < 0) { /* detection and identification */ 468 u8 man_id, chip_id, reg_config1, reg_convrate; 469 470 if (lm90_read_reg(new_client, LM90_REG_R_MAN_ID, 471 &man_id) < 0 472 || lm90_read_reg(new_client, LM90_REG_R_CHIP_ID, 473 &chip_id) < 0 474 || lm90_read_reg(new_client, LM90_REG_R_CONFIG1, 475 ®_config1) < 0 476 || lm90_read_reg(new_client, LM90_REG_R_CONVRATE, 477 ®_convrate) < 0) 478 goto exit_free; 479 480 if (man_id == 0x01) { /* National Semiconductor */ 481 u8 reg_config2; 482 483 if (lm90_read_reg(new_client, LM90_REG_R_CONFIG2, 484 ®_config2) < 0) 485 goto exit_free; 486 487 if ((reg_config1 & 0x2A) == 0x00 488 && (reg_config2 & 0xF8) == 0x00 489 && reg_convrate <= 0x09) { 490 if (address == 0x4C 491 && (chip_id & 0xF0) == 0x20) { /* LM90 */ 492 kind = lm90; 493 } else 494 if ((chip_id & 0xF0) == 0x30) { /* LM89/LM99 */ 495 kind = lm99; 496 } else 497 if (address == 0x4C 498 && (chip_id & 0xF0) == 0x10) { /* LM86 */ 499 kind = lm86; 500 } 501 } 502 } else 503 if (man_id == 0x41) { /* Analog Devices */ 504 if ((chip_id & 0xF0) == 0x40 /* ADM1032 */ 505 && (reg_config1 & 0x3F) == 0x00 506 && reg_convrate <= 0x0A) { 507 kind = adm1032; 508 } else 509 if (chip_id == 0x51 /* ADT7461 */ 510 && (reg_config1 & 0x1F) == 0x00 /* check compat mode */ 511 && reg_convrate <= 0x0A) { 512 kind = adt7461; 513 } 514 } else 515 if (man_id == 0x4D) { /* Maxim */ 516 /* 517 * The Maxim variants do NOT have a chip_id register. 518 * Reading from that address will return the last read 519 * value, which in our case is those of the man_id 520 * register. Likewise, the config1 register seems to 521 * lack a low nibble, so the value will be those of the 522 * previous read, so in our case those of the man_id 523 * register. 524 */ 525 if (chip_id == man_id 526 && (reg_config1 & 0x1F) == (man_id & 0x0F) 527 && reg_convrate <= 0x09) { 528 kind = max6657; 529 } 530 } 531 532 if (kind <= 0) { /* identification failed */ 533 dev_info(&adapter->dev, 534 "Unsupported chip (man_id=0x%02X, " 535 "chip_id=0x%02X).\n", man_id, chip_id); 536 goto exit_free; 537 } 538 } 539 540 if (kind == lm90) { 541 name = "lm90"; 542 } else if (kind == adm1032) { 543 name = "adm1032"; 544 /* The ADM1032 supports PEC, but only if combined 545 transactions are not used. */ 546 if (i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE)) 547 new_client->flags |= I2C_CLIENT_PEC; 548 } else if (kind == lm99) { 549 name = "lm99"; 550 } else if (kind == lm86) { 551 name = "lm86"; 552 } else if (kind == max6657) { 553 name = "max6657"; 554 } else if (kind == adt7461) { 555 name = "adt7461"; 556 } 557 558 /* We can fill in the remaining client fields */ 559 strlcpy(new_client->name, name, I2C_NAME_SIZE); 560 data->valid = 0; 561 data->kind = kind; 562 mutex_init(&data->update_lock); 563 564 /* Tell the I2C layer a new client has arrived */ 565 if ((err = i2c_attach_client(new_client))) 566 goto exit_free; 567 568 /* Initialize the LM90 chip */ 569 lm90_init_client(new_client); 570 571 /* Register sysfs hooks */ 572 data->class_dev = hwmon_device_register(&new_client->dev); 573 if (IS_ERR(data->class_dev)) { 574 err = PTR_ERR(data->class_dev); 575 goto exit_detach; 576 } 577 578 device_create_file(&new_client->dev, 579 &sensor_dev_attr_temp1_input.dev_attr); 580 device_create_file(&new_client->dev, 581 &sensor_dev_attr_temp2_input.dev_attr); 582 device_create_file(&new_client->dev, 583 &sensor_dev_attr_temp1_min.dev_attr); 584 device_create_file(&new_client->dev, 585 &sensor_dev_attr_temp2_min.dev_attr); 586 device_create_file(&new_client->dev, 587 &sensor_dev_attr_temp1_max.dev_attr); 588 device_create_file(&new_client->dev, 589 &sensor_dev_attr_temp2_max.dev_attr); 590 device_create_file(&new_client->dev, 591 &sensor_dev_attr_temp1_crit.dev_attr); 592 device_create_file(&new_client->dev, 593 &sensor_dev_attr_temp2_crit.dev_attr); 594 device_create_file(&new_client->dev, 595 &sensor_dev_attr_temp1_crit_hyst.dev_attr); 596 device_create_file(&new_client->dev, 597 &sensor_dev_attr_temp2_crit_hyst.dev_attr); 598 device_create_file(&new_client->dev, &dev_attr_alarms); 599 600 if (new_client->flags & I2C_CLIENT_PEC) 601 device_create_file(&new_client->dev, &dev_attr_pec); 602 603 return 0; 604 605 exit_detach: 606 i2c_detach_client(new_client); 607 exit_free: 608 kfree(data); 609 exit: 610 return err; 611 } 612 613 static void lm90_init_client(struct i2c_client *client) 614 { 615 u8 config; 616 617 /* 618 * Start the conversions. 619 */ 620 i2c_smbus_write_byte_data(client, LM90_REG_W_CONVRATE, 621 5); /* 2 Hz */ 622 if (lm90_read_reg(client, LM90_REG_R_CONFIG1, &config) < 0) { 623 dev_warn(&client->dev, "Initialization failed!\n"); 624 return; 625 } 626 if (config & 0x40) 627 i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1, 628 config & 0xBF); /* run */ 629 } 630 631 static int lm90_detach_client(struct i2c_client *client) 632 { 633 struct lm90_data *data = i2c_get_clientdata(client); 634 int err; 635 636 hwmon_device_unregister(data->class_dev); 637 638 if ((err = i2c_detach_client(client))) 639 return err; 640 641 kfree(data); 642 return 0; 643 } 644 645 static struct lm90_data *lm90_update_device(struct device *dev) 646 { 647 struct i2c_client *client = to_i2c_client(dev); 648 struct lm90_data *data = i2c_get_clientdata(client); 649 650 mutex_lock(&data->update_lock); 651 652 if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) { 653 u8 oldh, newh, l; 654 655 dev_dbg(&client->dev, "Updating lm90 data.\n"); 656 lm90_read_reg(client, LM90_REG_R_LOCAL_TEMP, &data->temp8[0]); 657 lm90_read_reg(client, LM90_REG_R_LOCAL_LOW, &data->temp8[1]); 658 lm90_read_reg(client, LM90_REG_R_LOCAL_HIGH, &data->temp8[2]); 659 lm90_read_reg(client, LM90_REG_R_LOCAL_CRIT, &data->temp8[3]); 660 lm90_read_reg(client, LM90_REG_R_REMOTE_CRIT, &data->temp8[4]); 661 lm90_read_reg(client, LM90_REG_R_TCRIT_HYST, &data->temp_hyst); 662 663 /* 664 * There is a trick here. We have to read two registers to 665 * have the remote sensor temperature, but we have to beware 666 * a conversion could occur inbetween the readings. The 667 * datasheet says we should either use the one-shot 668 * conversion register, which we don't want to do (disables 669 * hardware monitoring) or monitor the busy bit, which is 670 * impossible (we can't read the values and monitor that bit 671 * at the exact same time). So the solution used here is to 672 * read the high byte once, then the low byte, then the high 673 * byte again. If the new high byte matches the old one, 674 * then we have a valid reading. Else we have to read the low 675 * byte again, and now we believe we have a correct reading. 676 */ 677 if (lm90_read_reg(client, LM90_REG_R_REMOTE_TEMPH, &oldh) == 0 678 && lm90_read_reg(client, LM90_REG_R_REMOTE_TEMPL, &l) == 0 679 && lm90_read_reg(client, LM90_REG_R_REMOTE_TEMPH, &newh) == 0 680 && (newh == oldh 681 || lm90_read_reg(client, LM90_REG_R_REMOTE_TEMPL, &l) == 0)) 682 data->temp11[0] = (newh << 8) | l; 683 684 if (lm90_read_reg(client, LM90_REG_R_REMOTE_LOWH, &newh) == 0 685 && lm90_read_reg(client, LM90_REG_R_REMOTE_LOWL, &l) == 0) 686 data->temp11[1] = (newh << 8) | l; 687 if (lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHH, &newh) == 0 688 && lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHL, &l) == 0) 689 data->temp11[2] = (newh << 8) | l; 690 lm90_read_reg(client, LM90_REG_R_STATUS, &data->alarms); 691 692 data->last_updated = jiffies; 693 data->valid = 1; 694 } 695 696 mutex_unlock(&data->update_lock); 697 698 return data; 699 } 700 701 static int __init sensors_lm90_init(void) 702 { 703 return i2c_add_driver(&lm90_driver); 704 } 705 706 static void __exit sensors_lm90_exit(void) 707 { 708 i2c_del_driver(&lm90_driver); 709 } 710 711 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>"); 712 MODULE_DESCRIPTION("LM90/ADM1032 driver"); 713 MODULE_LICENSE("GPL"); 714 715 module_init(sensors_lm90_init); 716 module_exit(sensors_lm90_exit); 717