1 /* 2 * lm83.c - Part of lm_sensors, Linux kernel modules for hardware 3 * monitoring 4 * Copyright (C) 2003-2006 Jean Delvare <khali@linux-fr.org> 5 * 6 * Heavily inspired from the lm78, lm75 and adm1021 drivers. The LM83 is 7 * a sensor chip made by National Semiconductor. It reports up to four 8 * temperatures (its own plus up to three external ones) with a 1 deg 9 * resolution and a 3-4 deg accuracy. Complete datasheet can be obtained 10 * from National's website at: 11 * http://www.national.com/pf/LM/LM83.html 12 * Since the datasheet omits to give the chip stepping code, I give it 13 * here: 0x03 (at register 0xff). 14 * 15 * Also supports the LM82 temp sensor, which is basically a stripped down 16 * model of the LM83. Datasheet is here: 17 * http://www.national.com/pf/LM/LM82.html 18 * 19 * This program is free software; you can redistribute it and/or modify 20 * it under the terms of the GNU General Public License as published by 21 * the Free Software Foundation; either version 2 of the License, or 22 * (at your option) any later version. 23 * 24 * This program is distributed in the hope that it will be useful, 25 * but WITHOUT ANY WARRANTY; without even the implied warranty of 26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 27 * GNU General Public License for more details. 28 * 29 * You should have received a copy of the GNU General Public License 30 * along with this program; if not, write to the Free Software 31 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 32 */ 33 34 #include <linux/module.h> 35 #include <linux/init.h> 36 #include <linux/slab.h> 37 #include <linux/jiffies.h> 38 #include <linux/i2c.h> 39 #include <linux/hwmon-sysfs.h> 40 #include <linux/hwmon.h> 41 #include <linux/err.h> 42 #include <linux/mutex.h> 43 #include <linux/sysfs.h> 44 45 /* 46 * Addresses to scan 47 * Address is selected using 2 three-level pins, resulting in 9 possible 48 * addresses. 49 */ 50 51 static const unsigned short normal_i2c[] = { 52 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END }; 53 54 /* 55 * Insmod parameters 56 */ 57 58 I2C_CLIENT_INSMOD_2(lm83, lm82); 59 60 /* 61 * The LM83 registers 62 * Manufacturer ID is 0x01 for National Semiconductor. 63 */ 64 65 #define LM83_REG_R_MAN_ID 0xFE 66 #define LM83_REG_R_CHIP_ID 0xFF 67 #define LM83_REG_R_CONFIG 0x03 68 #define LM83_REG_W_CONFIG 0x09 69 #define LM83_REG_R_STATUS1 0x02 70 #define LM83_REG_R_STATUS2 0x35 71 #define LM83_REG_R_LOCAL_TEMP 0x00 72 #define LM83_REG_R_LOCAL_HIGH 0x05 73 #define LM83_REG_W_LOCAL_HIGH 0x0B 74 #define LM83_REG_R_REMOTE1_TEMP 0x30 75 #define LM83_REG_R_REMOTE1_HIGH 0x38 76 #define LM83_REG_W_REMOTE1_HIGH 0x50 77 #define LM83_REG_R_REMOTE2_TEMP 0x01 78 #define LM83_REG_R_REMOTE2_HIGH 0x07 79 #define LM83_REG_W_REMOTE2_HIGH 0x0D 80 #define LM83_REG_R_REMOTE3_TEMP 0x31 81 #define LM83_REG_R_REMOTE3_HIGH 0x3A 82 #define LM83_REG_W_REMOTE3_HIGH 0x52 83 #define LM83_REG_R_TCRIT 0x42 84 #define LM83_REG_W_TCRIT 0x5A 85 86 /* 87 * Conversions and various macros 88 * The LM83 uses signed 8-bit values with LSB = 1 degree Celsius. 89 */ 90 91 #define TEMP_FROM_REG(val) ((val) * 1000) 92 #define TEMP_TO_REG(val) ((val) <= -128000 ? -128 : \ 93 (val) >= 127000 ? 127 : \ 94 (val) < 0 ? ((val) - 500) / 1000 : \ 95 ((val) + 500) / 1000) 96 97 static const u8 LM83_REG_R_TEMP[] = { 98 LM83_REG_R_LOCAL_TEMP, 99 LM83_REG_R_REMOTE1_TEMP, 100 LM83_REG_R_REMOTE2_TEMP, 101 LM83_REG_R_REMOTE3_TEMP, 102 LM83_REG_R_LOCAL_HIGH, 103 LM83_REG_R_REMOTE1_HIGH, 104 LM83_REG_R_REMOTE2_HIGH, 105 LM83_REG_R_REMOTE3_HIGH, 106 LM83_REG_R_TCRIT, 107 }; 108 109 static const u8 LM83_REG_W_HIGH[] = { 110 LM83_REG_W_LOCAL_HIGH, 111 LM83_REG_W_REMOTE1_HIGH, 112 LM83_REG_W_REMOTE2_HIGH, 113 LM83_REG_W_REMOTE3_HIGH, 114 LM83_REG_W_TCRIT, 115 }; 116 117 /* 118 * Functions declaration 119 */ 120 121 static int lm83_attach_adapter(struct i2c_adapter *adapter); 122 static int lm83_detect(struct i2c_adapter *adapter, int address, int kind); 123 static int lm83_detach_client(struct i2c_client *client); 124 static struct lm83_data *lm83_update_device(struct device *dev); 125 126 /* 127 * Driver data (common to all clients) 128 */ 129 130 static struct i2c_driver lm83_driver = { 131 .driver = { 132 .name = "lm83", 133 }, 134 .attach_adapter = lm83_attach_adapter, 135 .detach_client = lm83_detach_client, 136 }; 137 138 /* 139 * Client data (each client gets its own) 140 */ 141 142 struct lm83_data { 143 struct i2c_client client; 144 struct device *hwmon_dev; 145 struct mutex update_lock; 146 char valid; /* zero until following fields are valid */ 147 unsigned long last_updated; /* in jiffies */ 148 149 /* registers values */ 150 s8 temp[9]; /* 0..3: input 1-4, 151 4..7: high limit 1-4, 152 8 : critical limit */ 153 u16 alarms; /* bitvector, combined */ 154 }; 155 156 /* 157 * Sysfs stuff 158 */ 159 160 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, 161 char *buf) 162 { 163 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 164 struct lm83_data *data = lm83_update_device(dev); 165 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index])); 166 } 167 168 static ssize_t set_temp(struct device *dev, struct device_attribute *devattr, 169 const char *buf, size_t count) 170 { 171 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 172 struct i2c_client *client = to_i2c_client(dev); 173 struct lm83_data *data = i2c_get_clientdata(client); 174 long val = simple_strtol(buf, NULL, 10); 175 int nr = attr->index; 176 177 mutex_lock(&data->update_lock); 178 data->temp[nr] = TEMP_TO_REG(val); 179 i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr - 4], 180 data->temp[nr]); 181 mutex_unlock(&data->update_lock); 182 return count; 183 } 184 185 static ssize_t show_alarms(struct device *dev, struct device_attribute *dummy, 186 char *buf) 187 { 188 struct lm83_data *data = lm83_update_device(dev); 189 return sprintf(buf, "%d\n", data->alarms); 190 } 191 192 static ssize_t show_alarm(struct device *dev, struct device_attribute 193 *devattr, char *buf) 194 { 195 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 196 struct lm83_data *data = lm83_update_device(dev); 197 int bitnr = attr->index; 198 199 return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1); 200 } 201 202 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0); 203 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1); 204 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2); 205 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3); 206 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp, 207 set_temp, 4); 208 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp, 209 set_temp, 5); 210 static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_temp, 211 set_temp, 6); 212 static SENSOR_DEVICE_ATTR(temp4_max, S_IWUSR | S_IRUGO, show_temp, 213 set_temp, 7); 214 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, 8); 215 static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO, show_temp, NULL, 8); 216 static SENSOR_DEVICE_ATTR(temp3_crit, S_IWUSR | S_IRUGO, show_temp, 217 set_temp, 8); 218 static SENSOR_DEVICE_ATTR(temp4_crit, S_IRUGO, show_temp, NULL, 8); 219 220 /* Individual alarm files */ 221 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 0); 222 static SENSOR_DEVICE_ATTR(temp3_crit_alarm, S_IRUGO, show_alarm, NULL, 1); 223 static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_alarm, NULL, 2); 224 static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_alarm, NULL, 4); 225 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 6); 226 static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 8); 227 static SENSOR_DEVICE_ATTR(temp4_crit_alarm, S_IRUGO, show_alarm, NULL, 9); 228 static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_alarm, NULL, 10); 229 static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_alarm, NULL, 12); 230 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 13); 231 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 15); 232 /* Raw alarm file for compatibility */ 233 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL); 234 235 static struct attribute *lm83_attributes[] = { 236 &sensor_dev_attr_temp1_input.dev_attr.attr, 237 &sensor_dev_attr_temp3_input.dev_attr.attr, 238 &sensor_dev_attr_temp1_max.dev_attr.attr, 239 &sensor_dev_attr_temp3_max.dev_attr.attr, 240 &sensor_dev_attr_temp1_crit.dev_attr.attr, 241 &sensor_dev_attr_temp3_crit.dev_attr.attr, 242 243 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, 244 &sensor_dev_attr_temp3_crit_alarm.dev_attr.attr, 245 &sensor_dev_attr_temp3_fault.dev_attr.attr, 246 &sensor_dev_attr_temp3_max_alarm.dev_attr.attr, 247 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, 248 &dev_attr_alarms.attr, 249 NULL 250 }; 251 252 static const struct attribute_group lm83_group = { 253 .attrs = lm83_attributes, 254 }; 255 256 static struct attribute *lm83_attributes_opt[] = { 257 &sensor_dev_attr_temp2_input.dev_attr.attr, 258 &sensor_dev_attr_temp4_input.dev_attr.attr, 259 &sensor_dev_attr_temp2_max.dev_attr.attr, 260 &sensor_dev_attr_temp4_max.dev_attr.attr, 261 &sensor_dev_attr_temp2_crit.dev_attr.attr, 262 &sensor_dev_attr_temp4_crit.dev_attr.attr, 263 264 &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr, 265 &sensor_dev_attr_temp4_crit_alarm.dev_attr.attr, 266 &sensor_dev_attr_temp4_fault.dev_attr.attr, 267 &sensor_dev_attr_temp4_max_alarm.dev_attr.attr, 268 &sensor_dev_attr_temp2_fault.dev_attr.attr, 269 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr, 270 NULL 271 }; 272 273 static const struct attribute_group lm83_group_opt = { 274 .attrs = lm83_attributes_opt, 275 }; 276 277 /* 278 * Real code 279 */ 280 281 static int lm83_attach_adapter(struct i2c_adapter *adapter) 282 { 283 if (!(adapter->class & I2C_CLASS_HWMON)) 284 return 0; 285 return i2c_probe(adapter, &addr_data, lm83_detect); 286 } 287 288 /* 289 * The following function does more than just detection. If detection 290 * succeeds, it also registers the new chip. 291 */ 292 static int lm83_detect(struct i2c_adapter *adapter, int address, int kind) 293 { 294 struct i2c_client *new_client; 295 struct lm83_data *data; 296 int err = 0; 297 const char *name = ""; 298 299 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 300 goto exit; 301 302 if (!(data = kzalloc(sizeof(struct lm83_data), GFP_KERNEL))) { 303 err = -ENOMEM; 304 goto exit; 305 } 306 307 /* The common I2C client data is placed right after the 308 * LM83-specific data. */ 309 new_client = &data->client; 310 i2c_set_clientdata(new_client, data); 311 new_client->addr = address; 312 new_client->adapter = adapter; 313 new_client->driver = &lm83_driver; 314 new_client->flags = 0; 315 316 /* Now we do the detection and identification. A negative kind 317 * means that the driver was loaded with no force parameter 318 * (default), so we must both detect and identify the chip 319 * (actually there is only one possible kind of chip for now, LM83). 320 * A zero kind means that the driver was loaded with the force 321 * parameter, the detection step shall be skipped. A positive kind 322 * means that the driver was loaded with the force parameter and a 323 * given kind of chip is requested, so both the detection and the 324 * identification steps are skipped. */ 325 326 /* Default to an LM83 if forced */ 327 if (kind == 0) 328 kind = lm83; 329 330 if (kind < 0) { /* detection */ 331 if (((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1) 332 & 0xA8) != 0x00) || 333 ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2) 334 & 0x48) != 0x00) || 335 ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG) 336 & 0x41) != 0x00)) { 337 dev_dbg(&adapter->dev, 338 "LM83 detection failed at 0x%02x.\n", address); 339 goto exit_free; 340 } 341 } 342 343 if (kind <= 0) { /* identification */ 344 u8 man_id, chip_id; 345 346 man_id = i2c_smbus_read_byte_data(new_client, 347 LM83_REG_R_MAN_ID); 348 chip_id = i2c_smbus_read_byte_data(new_client, 349 LM83_REG_R_CHIP_ID); 350 351 if (man_id == 0x01) { /* National Semiconductor */ 352 if (chip_id == 0x03) { 353 kind = lm83; 354 } else 355 if (chip_id == 0x01) { 356 kind = lm82; 357 } 358 } 359 360 if (kind <= 0) { /* identification failed */ 361 dev_info(&adapter->dev, 362 "Unsupported chip (man_id=0x%02X, " 363 "chip_id=0x%02X).\n", man_id, chip_id); 364 goto exit_free; 365 } 366 } 367 368 if (kind == lm83) { 369 name = "lm83"; 370 } else 371 if (kind == lm82) { 372 name = "lm82"; 373 } 374 375 /* We can fill in the remaining client fields */ 376 strlcpy(new_client->name, name, I2C_NAME_SIZE); 377 data->valid = 0; 378 mutex_init(&data->update_lock); 379 380 /* Tell the I2C layer a new client has arrived */ 381 if ((err = i2c_attach_client(new_client))) 382 goto exit_free; 383 384 /* 385 * Register sysfs hooks 386 * The LM82 can only monitor one external diode which is 387 * at the same register as the LM83 temp3 entry - so we 388 * declare 1 and 3 common, and then 2 and 4 only for the LM83. 389 */ 390 391 if ((err = sysfs_create_group(&new_client->dev.kobj, &lm83_group))) 392 goto exit_detach; 393 394 if (kind == lm83) { 395 if ((err = sysfs_create_group(&new_client->dev.kobj, 396 &lm83_group_opt))) 397 goto exit_remove_files; 398 } 399 400 data->hwmon_dev = hwmon_device_register(&new_client->dev); 401 if (IS_ERR(data->hwmon_dev)) { 402 err = PTR_ERR(data->hwmon_dev); 403 goto exit_remove_files; 404 } 405 406 return 0; 407 408 exit_remove_files: 409 sysfs_remove_group(&new_client->dev.kobj, &lm83_group); 410 sysfs_remove_group(&new_client->dev.kobj, &lm83_group_opt); 411 exit_detach: 412 i2c_detach_client(new_client); 413 exit_free: 414 kfree(data); 415 exit: 416 return err; 417 } 418 419 static int lm83_detach_client(struct i2c_client *client) 420 { 421 struct lm83_data *data = i2c_get_clientdata(client); 422 int err; 423 424 hwmon_device_unregister(data->hwmon_dev); 425 sysfs_remove_group(&client->dev.kobj, &lm83_group); 426 sysfs_remove_group(&client->dev.kobj, &lm83_group_opt); 427 428 if ((err = i2c_detach_client(client))) 429 return err; 430 431 kfree(data); 432 return 0; 433 } 434 435 static struct lm83_data *lm83_update_device(struct device *dev) 436 { 437 struct i2c_client *client = to_i2c_client(dev); 438 struct lm83_data *data = i2c_get_clientdata(client); 439 440 mutex_lock(&data->update_lock); 441 442 if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) { 443 int nr; 444 445 dev_dbg(&client->dev, "Updating lm83 data.\n"); 446 for (nr = 0; nr < 9; nr++) { 447 data->temp[nr] = 448 i2c_smbus_read_byte_data(client, 449 LM83_REG_R_TEMP[nr]); 450 } 451 data->alarms = 452 i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1) 453 + (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2) 454 << 8); 455 456 data->last_updated = jiffies; 457 data->valid = 1; 458 } 459 460 mutex_unlock(&data->update_lock); 461 462 return data; 463 } 464 465 static int __init sensors_lm83_init(void) 466 { 467 return i2c_add_driver(&lm83_driver); 468 } 469 470 static void __exit sensors_lm83_exit(void) 471 { 472 i2c_del_driver(&lm83_driver); 473 } 474 475 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>"); 476 MODULE_DESCRIPTION("LM83 driver"); 477 MODULE_LICENSE("GPL"); 478 479 module_init(sensors_lm83_init); 480 module_exit(sensors_lm83_exit); 481