1 /* 2 * lm83.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 * 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 44 /* 45 * Addresses to scan 46 * Address is selected using 2 three-level pins, resulting in 9 possible 47 * addresses. 48 */ 49 50 static unsigned short normal_i2c[] = { 0x18, 0x19, 0x1a, 51 0x29, 0x2a, 0x2b, 52 0x4c, 0x4d, 0x4e, 53 I2C_CLIENT_END }; 54 55 /* 56 * Insmod parameters 57 */ 58 59 I2C_CLIENT_INSMOD_2(lm83, lm82); 60 61 /* 62 * The LM83 registers 63 * Manufacturer ID is 0x01 for National Semiconductor. 64 */ 65 66 #define LM83_REG_R_MAN_ID 0xFE 67 #define LM83_REG_R_CHIP_ID 0xFF 68 #define LM83_REG_R_CONFIG 0x03 69 #define LM83_REG_W_CONFIG 0x09 70 #define LM83_REG_R_STATUS1 0x02 71 #define LM83_REG_R_STATUS2 0x35 72 #define LM83_REG_R_LOCAL_TEMP 0x00 73 #define LM83_REG_R_LOCAL_HIGH 0x05 74 #define LM83_REG_W_LOCAL_HIGH 0x0B 75 #define LM83_REG_R_REMOTE1_TEMP 0x30 76 #define LM83_REG_R_REMOTE1_HIGH 0x38 77 #define LM83_REG_W_REMOTE1_HIGH 0x50 78 #define LM83_REG_R_REMOTE2_TEMP 0x01 79 #define LM83_REG_R_REMOTE2_HIGH 0x07 80 #define LM83_REG_W_REMOTE2_HIGH 0x0D 81 #define LM83_REG_R_REMOTE3_TEMP 0x31 82 #define LM83_REG_R_REMOTE3_HIGH 0x3A 83 #define LM83_REG_W_REMOTE3_HIGH 0x52 84 #define LM83_REG_R_TCRIT 0x42 85 #define LM83_REG_W_TCRIT 0x5A 86 87 /* 88 * Conversions and various macros 89 * The LM83 uses signed 8-bit values with LSB = 1 degree Celsius. 90 */ 91 92 #define TEMP_FROM_REG(val) ((val) * 1000) 93 #define TEMP_TO_REG(val) ((val) <= -128000 ? -128 : \ 94 (val) >= 127000 ? 127 : \ 95 (val) < 0 ? ((val) - 500) / 1000 : \ 96 ((val) + 500) / 1000) 97 98 static const u8 LM83_REG_R_TEMP[] = { 99 LM83_REG_R_LOCAL_TEMP, 100 LM83_REG_R_REMOTE1_TEMP, 101 LM83_REG_R_REMOTE2_TEMP, 102 LM83_REG_R_REMOTE3_TEMP, 103 LM83_REG_R_LOCAL_HIGH, 104 LM83_REG_R_REMOTE1_HIGH, 105 LM83_REG_R_REMOTE2_HIGH, 106 LM83_REG_R_REMOTE3_HIGH, 107 LM83_REG_R_TCRIT, 108 }; 109 110 static const u8 LM83_REG_W_HIGH[] = { 111 LM83_REG_W_LOCAL_HIGH, 112 LM83_REG_W_REMOTE1_HIGH, 113 LM83_REG_W_REMOTE2_HIGH, 114 LM83_REG_W_REMOTE3_HIGH, 115 LM83_REG_W_TCRIT, 116 }; 117 118 /* 119 * Functions declaration 120 */ 121 122 static int lm83_attach_adapter(struct i2c_adapter *adapter); 123 static int lm83_detect(struct i2c_adapter *adapter, int address, int kind); 124 static int lm83_detach_client(struct i2c_client *client); 125 static struct lm83_data *lm83_update_device(struct device *dev); 126 127 /* 128 * Driver data (common to all clients) 129 */ 130 131 static struct i2c_driver lm83_driver = { 132 .driver = { 133 .name = "lm83", 134 }, 135 .id = I2C_DRIVERID_LM83, 136 .attach_adapter = lm83_attach_adapter, 137 .detach_client = lm83_detach_client, 138 }; 139 140 /* 141 * Client data (each client gets its own) 142 */ 143 144 struct lm83_data { 145 struct i2c_client client; 146 struct class_device *class_dev; 147 struct mutex update_lock; 148 char valid; /* zero until following fields are valid */ 149 unsigned long last_updated; /* in jiffies */ 150 151 /* registers values */ 152 s8 temp[9]; /* 0..3: input 1-4, 153 4..7: high limit 1-4, 154 8 : critical limit */ 155 u16 alarms; /* bitvector, combined */ 156 }; 157 158 /* 159 * Sysfs stuff 160 */ 161 162 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, 163 char *buf) 164 { 165 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 166 struct lm83_data *data = lm83_update_device(dev); 167 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index])); 168 } 169 170 static ssize_t set_temp(struct device *dev, struct device_attribute *devattr, 171 const char *buf, size_t count) 172 { 173 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 174 struct i2c_client *client = to_i2c_client(dev); 175 struct lm83_data *data = i2c_get_clientdata(client); 176 long val = simple_strtol(buf, NULL, 10); 177 int nr = attr->index; 178 179 mutex_lock(&data->update_lock); 180 data->temp[nr] = TEMP_TO_REG(val); 181 i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr - 4], 182 data->temp[nr]); 183 mutex_unlock(&data->update_lock); 184 return count; 185 } 186 187 static ssize_t show_alarms(struct device *dev, struct device_attribute *dummy, 188 char *buf) 189 { 190 struct lm83_data *data = lm83_update_device(dev); 191 return sprintf(buf, "%d\n", data->alarms); 192 } 193 194 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0); 195 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1); 196 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2); 197 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3); 198 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp, 199 set_temp, 4); 200 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp, 201 set_temp, 5); 202 static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_temp, 203 set_temp, 6); 204 static SENSOR_DEVICE_ATTR(temp4_max, S_IWUSR | S_IRUGO, show_temp, 205 set_temp, 7); 206 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, 8); 207 static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO, show_temp, NULL, 8); 208 static SENSOR_DEVICE_ATTR(temp3_crit, S_IWUSR | S_IRUGO, show_temp, 209 set_temp, 8); 210 static SENSOR_DEVICE_ATTR(temp4_crit, S_IRUGO, show_temp, NULL, 8); 211 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL); 212 213 /* 214 * Real code 215 */ 216 217 static int lm83_attach_adapter(struct i2c_adapter *adapter) 218 { 219 if (!(adapter->class & I2C_CLASS_HWMON)) 220 return 0; 221 return i2c_probe(adapter, &addr_data, lm83_detect); 222 } 223 224 /* 225 * The following function does more than just detection. If detection 226 * succeeds, it also registers the new chip. 227 */ 228 static int lm83_detect(struct i2c_adapter *adapter, int address, int kind) 229 { 230 struct i2c_client *new_client; 231 struct lm83_data *data; 232 int err = 0; 233 const char *name = ""; 234 235 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 236 goto exit; 237 238 if (!(data = kzalloc(sizeof(struct lm83_data), GFP_KERNEL))) { 239 err = -ENOMEM; 240 goto exit; 241 } 242 243 /* The common I2C client data is placed right after the 244 * LM83-specific data. */ 245 new_client = &data->client; 246 i2c_set_clientdata(new_client, data); 247 new_client->addr = address; 248 new_client->adapter = adapter; 249 new_client->driver = &lm83_driver; 250 new_client->flags = 0; 251 252 /* Now we do the detection and identification. A negative kind 253 * means that the driver was loaded with no force parameter 254 * (default), so we must both detect and identify the chip 255 * (actually there is only one possible kind of chip for now, LM83). 256 * A zero kind means that the driver was loaded with the force 257 * parameter, the detection step shall be skipped. A positive kind 258 * means that the driver was loaded with the force parameter and a 259 * given kind of chip is requested, so both the detection and the 260 * identification steps are skipped. */ 261 262 /* Default to an LM83 if forced */ 263 if (kind == 0) 264 kind = lm83; 265 266 if (kind < 0) { /* detection */ 267 if (((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1) 268 & 0xA8) != 0x00) || 269 ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2) 270 & 0x48) != 0x00) || 271 ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG) 272 & 0x41) != 0x00)) { 273 dev_dbg(&adapter->dev, 274 "LM83 detection failed at 0x%02x.\n", address); 275 goto exit_free; 276 } 277 } 278 279 if (kind <= 0) { /* identification */ 280 u8 man_id, chip_id; 281 282 man_id = i2c_smbus_read_byte_data(new_client, 283 LM83_REG_R_MAN_ID); 284 chip_id = i2c_smbus_read_byte_data(new_client, 285 LM83_REG_R_CHIP_ID); 286 287 if (man_id == 0x01) { /* National Semiconductor */ 288 if (chip_id == 0x03) { 289 kind = lm83; 290 } else 291 if (chip_id == 0x01) { 292 kind = lm82; 293 } 294 } 295 296 if (kind <= 0) { /* identification failed */ 297 dev_info(&adapter->dev, 298 "Unsupported chip (man_id=0x%02X, " 299 "chip_id=0x%02X).\n", man_id, chip_id); 300 goto exit_free; 301 } 302 } 303 304 if (kind == lm83) { 305 name = "lm83"; 306 } else 307 if (kind == lm82) { 308 name = "lm82"; 309 } 310 311 /* We can fill in the remaining client fields */ 312 strlcpy(new_client->name, name, I2C_NAME_SIZE); 313 data->valid = 0; 314 mutex_init(&data->update_lock); 315 316 /* Tell the I2C layer a new client has arrived */ 317 if ((err = i2c_attach_client(new_client))) 318 goto exit_free; 319 320 /* 321 * Initialize the LM83 chip 322 * (Nothing to do for this one.) 323 */ 324 325 /* Register sysfs hooks */ 326 data->class_dev = hwmon_device_register(&new_client->dev); 327 if (IS_ERR(data->class_dev)) { 328 err = PTR_ERR(data->class_dev); 329 goto exit_detach; 330 } 331 332 /* 333 * The LM82 can only monitor one external diode which is 334 * at the same register as the LM83 temp3 entry - so we 335 * declare 1 and 3 common, and then 2 and 4 only for the LM83. 336 */ 337 338 device_create_file(&new_client->dev, 339 &sensor_dev_attr_temp1_input.dev_attr); 340 device_create_file(&new_client->dev, 341 &sensor_dev_attr_temp3_input.dev_attr); 342 343 device_create_file(&new_client->dev, 344 &sensor_dev_attr_temp1_max.dev_attr); 345 device_create_file(&new_client->dev, 346 &sensor_dev_attr_temp3_max.dev_attr); 347 348 device_create_file(&new_client->dev, 349 &sensor_dev_attr_temp1_crit.dev_attr); 350 device_create_file(&new_client->dev, 351 &sensor_dev_attr_temp3_crit.dev_attr); 352 353 device_create_file(&new_client->dev, &dev_attr_alarms); 354 355 if (kind == lm83) { 356 device_create_file(&new_client->dev, 357 &sensor_dev_attr_temp2_input.dev_attr); 358 device_create_file(&new_client->dev, 359 &sensor_dev_attr_temp4_input.dev_attr); 360 361 device_create_file(&new_client->dev, 362 &sensor_dev_attr_temp2_max.dev_attr); 363 device_create_file(&new_client->dev, 364 &sensor_dev_attr_temp4_max.dev_attr); 365 366 device_create_file(&new_client->dev, 367 &sensor_dev_attr_temp2_crit.dev_attr); 368 device_create_file(&new_client->dev, 369 &sensor_dev_attr_temp4_crit.dev_attr); 370 } 371 372 return 0; 373 374 exit_detach: 375 i2c_detach_client(new_client); 376 exit_free: 377 kfree(data); 378 exit: 379 return err; 380 } 381 382 static int lm83_detach_client(struct i2c_client *client) 383 { 384 struct lm83_data *data = i2c_get_clientdata(client); 385 int err; 386 387 hwmon_device_unregister(data->class_dev); 388 389 if ((err = i2c_detach_client(client))) 390 return err; 391 392 kfree(data); 393 return 0; 394 } 395 396 static struct lm83_data *lm83_update_device(struct device *dev) 397 { 398 struct i2c_client *client = to_i2c_client(dev); 399 struct lm83_data *data = i2c_get_clientdata(client); 400 401 mutex_lock(&data->update_lock); 402 403 if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) { 404 int nr; 405 406 dev_dbg(&client->dev, "Updating lm83 data.\n"); 407 for (nr = 0; nr < 9; nr++) { 408 data->temp[nr] = 409 i2c_smbus_read_byte_data(client, 410 LM83_REG_R_TEMP[nr]); 411 } 412 data->alarms = 413 i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1) 414 + (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2) 415 << 8); 416 417 data->last_updated = jiffies; 418 data->valid = 1; 419 } 420 421 mutex_unlock(&data->update_lock); 422 423 return data; 424 } 425 426 static int __init sensors_lm83_init(void) 427 { 428 return i2c_add_driver(&lm83_driver); 429 } 430 431 static void __exit sensors_lm83_exit(void) 432 { 433 i2c_del_driver(&lm83_driver); 434 } 435 436 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>"); 437 MODULE_DESCRIPTION("LM83 driver"); 438 MODULE_LICENSE("GPL"); 439 440 module_init(sensors_lm83_init); 441 module_exit(sensors_lm83_exit); 442