1/* 2 * lm83.c - Part of lm_sensors, Linux kernel modules for hardware 3 * monitoring 4 * Copyright (C) 2003-2009 Jean Delvare <jdelvare@suse.de> 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 30#include <linux/module.h> 31#include <linux/init.h> 32#include <linux/slab.h> 33#include <linux/jiffies.h> 34#include <linux/i2c.h> 35#include <linux/hwmon-sysfs.h> 36#include <linux/hwmon.h> 37#include <linux/err.h> 38#include <linux/mutex.h> 39#include <linux/sysfs.h> 40 41/* 42 * Addresses to scan 43 * Address is selected using 2 three-level pins, resulting in 9 possible 44 * addresses. 45 */ 46 47static const unsigned short normal_i2c[] = { 48 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END }; 49 50enum chips { lm83, lm82 }; 51 52/* 53 * The LM83 registers 54 * Manufacturer ID is 0x01 for National Semiconductor. 55 */ 56 57#define LM83_REG_R_MAN_ID 0xFE 58#define LM83_REG_R_CHIP_ID 0xFF 59#define LM83_REG_R_CONFIG 0x03 60#define LM83_REG_W_CONFIG 0x09 61#define LM83_REG_R_STATUS1 0x02 62#define LM83_REG_R_STATUS2 0x35 63#define LM83_REG_R_LOCAL_TEMP 0x00 64#define LM83_REG_R_LOCAL_HIGH 0x05 65#define LM83_REG_W_LOCAL_HIGH 0x0B 66#define LM83_REG_R_REMOTE1_TEMP 0x30 67#define LM83_REG_R_REMOTE1_HIGH 0x38 68#define LM83_REG_W_REMOTE1_HIGH 0x50 69#define LM83_REG_R_REMOTE2_TEMP 0x01 70#define LM83_REG_R_REMOTE2_HIGH 0x07 71#define LM83_REG_W_REMOTE2_HIGH 0x0D 72#define LM83_REG_R_REMOTE3_TEMP 0x31 73#define LM83_REG_R_REMOTE3_HIGH 0x3A 74#define LM83_REG_W_REMOTE3_HIGH 0x52 75#define LM83_REG_R_TCRIT 0x42 76#define LM83_REG_W_TCRIT 0x5A 77 78/* 79 * Conversions and various macros 80 * The LM83 uses signed 8-bit values with LSB = 1 degree Celsius. 81 */ 82 83#define TEMP_FROM_REG(val) ((val) * 1000) 84#define TEMP_TO_REG(val) ((val) <= -128000 ? -128 : \ 85 (val) >= 127000 ? 127 : \ 86 (val) < 0 ? ((val) - 500) / 1000 : \ 87 ((val) + 500) / 1000) 88 89static const u8 LM83_REG_R_TEMP[] = { 90 LM83_REG_R_LOCAL_TEMP, 91 LM83_REG_R_REMOTE1_TEMP, 92 LM83_REG_R_REMOTE2_TEMP, 93 LM83_REG_R_REMOTE3_TEMP, 94 LM83_REG_R_LOCAL_HIGH, 95 LM83_REG_R_REMOTE1_HIGH, 96 LM83_REG_R_REMOTE2_HIGH, 97 LM83_REG_R_REMOTE3_HIGH, 98 LM83_REG_R_TCRIT, 99}; 100 101static const u8 LM83_REG_W_HIGH[] = { 102 LM83_REG_W_LOCAL_HIGH, 103 LM83_REG_W_REMOTE1_HIGH, 104 LM83_REG_W_REMOTE2_HIGH, 105 LM83_REG_W_REMOTE3_HIGH, 106 LM83_REG_W_TCRIT, 107}; 108 109/* 110 * Client data (each client gets its own) 111 */ 112 113struct lm83_data { 114 struct i2c_client *client; 115 const struct attribute_group *groups[3]; 116 struct mutex update_lock; 117 char valid; /* zero until following fields are valid */ 118 unsigned long last_updated; /* in jiffies */ 119 120 /* registers values */ 121 s8 temp[9]; /* 0..3: input 1-4, 122 4..7: high limit 1-4, 123 8 : critical limit */ 124 u16 alarms; /* bitvector, combined */ 125}; 126 127static struct lm83_data *lm83_update_device(struct device *dev) 128{ 129 struct lm83_data *data = dev_get_drvdata(dev); 130 struct i2c_client *client = data->client; 131 132 mutex_lock(&data->update_lock); 133 134 if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) { 135 int nr; 136 137 dev_dbg(&client->dev, "Updating lm83 data.\n"); 138 for (nr = 0; nr < 9; nr++) { 139 data->temp[nr] = 140 i2c_smbus_read_byte_data(client, 141 LM83_REG_R_TEMP[nr]); 142 } 143 data->alarms = 144 i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1) 145 + (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2) 146 << 8); 147 148 data->last_updated = jiffies; 149 data->valid = 1; 150 } 151 152 mutex_unlock(&data->update_lock); 153 154 return data; 155} 156 157/* 158 * Sysfs stuff 159 */ 160 161static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, 162 char *buf) 163{ 164 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 165 struct lm83_data *data = lm83_update_device(dev); 166 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index])); 167} 168 169static ssize_t set_temp(struct device *dev, struct device_attribute *devattr, 170 const char *buf, size_t count) 171{ 172 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 173 struct lm83_data *data = dev_get_drvdata(dev); 174 struct i2c_client *client = data->client; 175 long val; 176 int nr = attr->index; 177 int err; 178 179 err = kstrtol(buf, 10, &val); 180 if (err < 0) 181 return err; 182 183 mutex_lock(&data->update_lock); 184 data->temp[nr] = TEMP_TO_REG(val); 185 i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr - 4], 186 data->temp[nr]); 187 mutex_unlock(&data->update_lock); 188 return count; 189} 190 191static ssize_t show_alarms(struct device *dev, struct device_attribute *dummy, 192 char *buf) 193{ 194 struct lm83_data *data = lm83_update_device(dev); 195 return sprintf(buf, "%d\n", data->alarms); 196} 197 198static ssize_t show_alarm(struct device *dev, struct device_attribute 199 *devattr, char *buf) 200{ 201 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 202 struct lm83_data *data = lm83_update_device(dev); 203 int bitnr = attr->index; 204 205 return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1); 206} 207 208static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0); 209static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1); 210static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2); 211static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3); 212static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp, 213 set_temp, 4); 214static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp, 215 set_temp, 5); 216static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_temp, 217 set_temp, 6); 218static SENSOR_DEVICE_ATTR(temp4_max, S_IWUSR | S_IRUGO, show_temp, 219 set_temp, 7); 220static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, 8); 221static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO, show_temp, NULL, 8); 222static SENSOR_DEVICE_ATTR(temp3_crit, S_IWUSR | S_IRUGO, show_temp, 223 set_temp, 8); 224static SENSOR_DEVICE_ATTR(temp4_crit, S_IRUGO, show_temp, NULL, 8); 225 226/* Individual alarm files */ 227static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 0); 228static SENSOR_DEVICE_ATTR(temp3_crit_alarm, S_IRUGO, show_alarm, NULL, 1); 229static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_alarm, NULL, 2); 230static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_alarm, NULL, 4); 231static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 6); 232static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 8); 233static SENSOR_DEVICE_ATTR(temp4_crit_alarm, S_IRUGO, show_alarm, NULL, 9); 234static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_alarm, NULL, 10); 235static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_alarm, NULL, 12); 236static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 13); 237static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 15); 238/* Raw alarm file for compatibility */ 239static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL); 240 241static struct attribute *lm83_attributes[] = { 242 &sensor_dev_attr_temp1_input.dev_attr.attr, 243 &sensor_dev_attr_temp3_input.dev_attr.attr, 244 &sensor_dev_attr_temp1_max.dev_attr.attr, 245 &sensor_dev_attr_temp3_max.dev_attr.attr, 246 &sensor_dev_attr_temp1_crit.dev_attr.attr, 247 &sensor_dev_attr_temp3_crit.dev_attr.attr, 248 249 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, 250 &sensor_dev_attr_temp3_crit_alarm.dev_attr.attr, 251 &sensor_dev_attr_temp3_fault.dev_attr.attr, 252 &sensor_dev_attr_temp3_max_alarm.dev_attr.attr, 253 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, 254 &dev_attr_alarms.attr, 255 NULL 256}; 257 258static const struct attribute_group lm83_group = { 259 .attrs = lm83_attributes, 260}; 261 262static struct attribute *lm83_attributes_opt[] = { 263 &sensor_dev_attr_temp2_input.dev_attr.attr, 264 &sensor_dev_attr_temp4_input.dev_attr.attr, 265 &sensor_dev_attr_temp2_max.dev_attr.attr, 266 &sensor_dev_attr_temp4_max.dev_attr.attr, 267 &sensor_dev_attr_temp2_crit.dev_attr.attr, 268 &sensor_dev_attr_temp4_crit.dev_attr.attr, 269 270 &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr, 271 &sensor_dev_attr_temp4_crit_alarm.dev_attr.attr, 272 &sensor_dev_attr_temp4_fault.dev_attr.attr, 273 &sensor_dev_attr_temp4_max_alarm.dev_attr.attr, 274 &sensor_dev_attr_temp2_fault.dev_attr.attr, 275 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr, 276 NULL 277}; 278 279static const struct attribute_group lm83_group_opt = { 280 .attrs = lm83_attributes_opt, 281}; 282 283/* 284 * Real code 285 */ 286 287/* Return 0 if detection is successful, -ENODEV otherwise */ 288static int lm83_detect(struct i2c_client *new_client, 289 struct i2c_board_info *info) 290{ 291 struct i2c_adapter *adapter = new_client->adapter; 292 const char *name; 293 u8 man_id, chip_id; 294 295 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 296 return -ENODEV; 297 298 /* Detection */ 299 if ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1) & 0xA8) || 300 (i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2) & 0x48) || 301 (i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG) & 0x41)) { 302 dev_dbg(&adapter->dev, "LM83 detection failed at 0x%02x\n", 303 new_client->addr); 304 return -ENODEV; 305 } 306 307 /* Identification */ 308 man_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_MAN_ID); 309 if (man_id != 0x01) /* National Semiconductor */ 310 return -ENODEV; 311 312 chip_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_CHIP_ID); 313 switch (chip_id) { 314 case 0x03: 315 name = "lm83"; 316 break; 317 case 0x01: 318 name = "lm82"; 319 break; 320 default: 321 /* identification failed */ 322 dev_info(&adapter->dev, 323 "Unsupported chip (man_id=0x%02X, chip_id=0x%02X)\n", 324 man_id, chip_id); 325 return -ENODEV; 326 } 327 328 strlcpy(info->type, name, I2C_NAME_SIZE); 329 330 return 0; 331} 332 333static int lm83_probe(struct i2c_client *new_client, 334 const struct i2c_device_id *id) 335{ 336 struct device *hwmon_dev; 337 struct lm83_data *data; 338 339 data = devm_kzalloc(&new_client->dev, sizeof(struct lm83_data), 340 GFP_KERNEL); 341 if (!data) 342 return -ENOMEM; 343 344 data->client = new_client; 345 mutex_init(&data->update_lock); 346 347 /* 348 * Register sysfs hooks 349 * The LM82 can only monitor one external diode which is 350 * at the same register as the LM83 temp3 entry - so we 351 * declare 1 and 3 common, and then 2 and 4 only for the LM83. 352 */ 353 data->groups[0] = &lm83_group; 354 if (id->driver_data == lm83) 355 data->groups[1] = &lm83_group_opt; 356 357 hwmon_dev = devm_hwmon_device_register_with_groups(&new_client->dev, 358 new_client->name, 359 data, data->groups); 360 return PTR_ERR_OR_ZERO(hwmon_dev); 361} 362 363/* 364 * Driver data (common to all clients) 365 */ 366 367static const struct i2c_device_id lm83_id[] = { 368 { "lm83", lm83 }, 369 { "lm82", lm82 }, 370 { } 371}; 372MODULE_DEVICE_TABLE(i2c, lm83_id); 373 374static struct i2c_driver lm83_driver = { 375 .class = I2C_CLASS_HWMON, 376 .driver = { 377 .name = "lm83", 378 }, 379 .probe = lm83_probe, 380 .id_table = lm83_id, 381 .detect = lm83_detect, 382 .address_list = normal_i2c, 383}; 384 385module_i2c_driver(lm83_driver); 386 387MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>"); 388MODULE_DESCRIPTION("LM83 driver"); 389MODULE_LICENSE("GPL"); 390