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 * This program is free software; you can redistribute it and/or modify 16 * it under the terms of the GNU General Public License as published by 17 * the Free Software Foundation; either version 2 of the License, or 18 * (at your option) any later version. 19 * 20 * This program is distributed in the hope that it will be useful, 21 * but WITHOUT ANY WARRANTY; without even the implied warranty of 22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 23 * GNU General Public License for more details. 24 * 25 * You should have received a copy of the GNU General Public License 26 * along with this program; if not, write to the Free Software 27 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 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 39 /* 40 * Addresses to scan 41 * Address is selected using 2 three-level pins, resulting in 9 possible 42 * addresses. 43 */ 44 45 static unsigned short normal_i2c[] = { 0x18, 0x19, 0x1a, 46 0x29, 0x2a, 0x2b, 47 0x4c, 0x4d, 0x4e, 48 I2C_CLIENT_END }; 49 50 /* 51 * Insmod parameters 52 */ 53 54 I2C_CLIENT_INSMOD_1(lm83); 55 56 /* 57 * The LM83 registers 58 * Manufacturer ID is 0x01 for National Semiconductor. 59 */ 60 61 #define LM83_REG_R_MAN_ID 0xFE 62 #define LM83_REG_R_CHIP_ID 0xFF 63 #define LM83_REG_R_CONFIG 0x03 64 #define LM83_REG_W_CONFIG 0x09 65 #define LM83_REG_R_STATUS1 0x02 66 #define LM83_REG_R_STATUS2 0x35 67 #define LM83_REG_R_LOCAL_TEMP 0x00 68 #define LM83_REG_R_LOCAL_HIGH 0x05 69 #define LM83_REG_W_LOCAL_HIGH 0x0B 70 #define LM83_REG_R_REMOTE1_TEMP 0x30 71 #define LM83_REG_R_REMOTE1_HIGH 0x38 72 #define LM83_REG_W_REMOTE1_HIGH 0x50 73 #define LM83_REG_R_REMOTE2_TEMP 0x01 74 #define LM83_REG_R_REMOTE2_HIGH 0x07 75 #define LM83_REG_W_REMOTE2_HIGH 0x0D 76 #define LM83_REG_R_REMOTE3_TEMP 0x31 77 #define LM83_REG_R_REMOTE3_HIGH 0x3A 78 #define LM83_REG_W_REMOTE3_HIGH 0x52 79 #define LM83_REG_R_TCRIT 0x42 80 #define LM83_REG_W_TCRIT 0x5A 81 82 /* 83 * Conversions and various macros 84 * The LM83 uses signed 8-bit values with LSB = 1 degree Celsius. 85 */ 86 87 #define TEMP_FROM_REG(val) ((val) * 1000) 88 #define TEMP_TO_REG(val) ((val) <= -128000 ? -128 : \ 89 (val) >= 127000 ? 127 : \ 90 (val) < 0 ? ((val) - 500) / 1000 : \ 91 ((val) + 500) / 1000) 92 93 static const u8 LM83_REG_R_TEMP[] = { 94 LM83_REG_R_LOCAL_TEMP, 95 LM83_REG_R_REMOTE1_TEMP, 96 LM83_REG_R_REMOTE2_TEMP, 97 LM83_REG_R_REMOTE3_TEMP, 98 LM83_REG_R_LOCAL_HIGH, 99 LM83_REG_R_REMOTE1_HIGH, 100 LM83_REG_R_REMOTE2_HIGH, 101 LM83_REG_R_REMOTE3_HIGH, 102 LM83_REG_R_TCRIT, 103 }; 104 105 static const u8 LM83_REG_W_HIGH[] = { 106 LM83_REG_W_LOCAL_HIGH, 107 LM83_REG_W_REMOTE1_HIGH, 108 LM83_REG_W_REMOTE2_HIGH, 109 LM83_REG_W_REMOTE3_HIGH, 110 LM83_REG_W_TCRIT, 111 }; 112 113 /* 114 * Functions declaration 115 */ 116 117 static int lm83_attach_adapter(struct i2c_adapter *adapter); 118 static int lm83_detect(struct i2c_adapter *adapter, int address, int kind); 119 static int lm83_detach_client(struct i2c_client *client); 120 static struct lm83_data *lm83_update_device(struct device *dev); 121 122 /* 123 * Driver data (common to all clients) 124 */ 125 126 static struct i2c_driver lm83_driver = { 127 .owner = THIS_MODULE, 128 .name = "lm83", 129 .id = I2C_DRIVERID_LM83, 130 .flags = I2C_DF_NOTIFY, 131 .attach_adapter = lm83_attach_adapter, 132 .detach_client = lm83_detach_client, 133 }; 134 135 /* 136 * Client data (each client gets its own) 137 */ 138 139 struct lm83_data { 140 struct i2c_client client; 141 struct class_device *class_dev; 142 struct semaphore update_lock; 143 char valid; /* zero until following fields are valid */ 144 unsigned long last_updated; /* in jiffies */ 145 146 /* registers values */ 147 s8 temp[9]; /* 0..3: input 1-4, 148 4..7: high limit 1-4, 149 8 : critical limit */ 150 u16 alarms; /* bitvector, combined */ 151 }; 152 153 /* 154 * Sysfs stuff 155 */ 156 157 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, 158 char *buf) 159 { 160 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 161 struct lm83_data *data = lm83_update_device(dev); 162 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index])); 163 } 164 165 static ssize_t set_temp(struct device *dev, struct device_attribute *devattr, 166 const char *buf, size_t count) 167 { 168 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 169 struct i2c_client *client = to_i2c_client(dev); 170 struct lm83_data *data = i2c_get_clientdata(client); 171 long val = simple_strtol(buf, NULL, 10); 172 int nr = attr->index; 173 174 down(&data->update_lock); 175 data->temp[nr] = TEMP_TO_REG(val); 176 i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr - 4], 177 data->temp[nr]); 178 up(&data->update_lock); 179 return count; 180 } 181 182 static ssize_t show_alarms(struct device *dev, struct device_attribute *dummy, 183 char *buf) 184 { 185 struct lm83_data *data = lm83_update_device(dev); 186 return sprintf(buf, "%d\n", data->alarms); 187 } 188 189 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0); 190 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1); 191 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2); 192 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3); 193 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp, 194 set_temp, 4); 195 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp, 196 set_temp, 5); 197 static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_temp, 198 set_temp, 6); 199 static SENSOR_DEVICE_ATTR(temp4_max, S_IWUSR | S_IRUGO, show_temp, 200 set_temp, 7); 201 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, 8); 202 static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO, show_temp, NULL, 8); 203 static SENSOR_DEVICE_ATTR(temp3_crit, S_IWUSR | S_IRUGO, show_temp, 204 set_temp, 8); 205 static SENSOR_DEVICE_ATTR(temp4_crit, S_IRUGO, show_temp, NULL, 8); 206 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL); 207 208 /* 209 * Real code 210 */ 211 212 static int lm83_attach_adapter(struct i2c_adapter *adapter) 213 { 214 if (!(adapter->class & I2C_CLASS_HWMON)) 215 return 0; 216 return i2c_probe(adapter, &addr_data, lm83_detect); 217 } 218 219 /* 220 * The following function does more than just detection. If detection 221 * succeeds, it also registers the new chip. 222 */ 223 static int lm83_detect(struct i2c_adapter *adapter, int address, int kind) 224 { 225 struct i2c_client *new_client; 226 struct lm83_data *data; 227 int err = 0; 228 const char *name = ""; 229 230 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 231 goto exit; 232 233 if (!(data = kmalloc(sizeof(struct lm83_data), GFP_KERNEL))) { 234 err = -ENOMEM; 235 goto exit; 236 } 237 memset(data, 0, sizeof(struct lm83_data)); 238 239 /* The common I2C client data is placed right after the 240 * LM83-specific data. */ 241 new_client = &data->client; 242 i2c_set_clientdata(new_client, data); 243 new_client->addr = address; 244 new_client->adapter = adapter; 245 new_client->driver = &lm83_driver; 246 new_client->flags = 0; 247 248 /* Now we do the detection and identification. A negative kind 249 * means that the driver was loaded with no force parameter 250 * (default), so we must both detect and identify the chip 251 * (actually there is only one possible kind of chip for now, LM83). 252 * A zero kind means that the driver was loaded with the force 253 * parameter, the detection step shall be skipped. A positive kind 254 * means that the driver was loaded with the force parameter and a 255 * given kind of chip is requested, so both the detection and the 256 * identification steps are skipped. */ 257 258 /* Default to an LM83 if forced */ 259 if (kind == 0) 260 kind = lm83; 261 262 if (kind < 0) { /* detection */ 263 if (((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1) 264 & 0xA8) != 0x00) || 265 ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2) 266 & 0x48) != 0x00) || 267 ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG) 268 & 0x41) != 0x00)) { 269 dev_dbg(&adapter->dev, 270 "LM83 detection failed at 0x%02x.\n", address); 271 goto exit_free; 272 } 273 } 274 275 if (kind <= 0) { /* identification */ 276 u8 man_id, chip_id; 277 278 man_id = i2c_smbus_read_byte_data(new_client, 279 LM83_REG_R_MAN_ID); 280 chip_id = i2c_smbus_read_byte_data(new_client, 281 LM83_REG_R_CHIP_ID); 282 283 if (man_id == 0x01) { /* National Semiconductor */ 284 if (chip_id == 0x03) { 285 kind = lm83; 286 } 287 } 288 289 if (kind <= 0) { /* identification failed */ 290 dev_info(&adapter->dev, 291 "Unsupported chip (man_id=0x%02X, " 292 "chip_id=0x%02X).\n", man_id, chip_id); 293 goto exit_free; 294 } 295 } 296 297 if (kind == lm83) { 298 name = "lm83"; 299 } 300 301 /* We can fill in the remaining client fields */ 302 strlcpy(new_client->name, name, I2C_NAME_SIZE); 303 data->valid = 0; 304 init_MUTEX(&data->update_lock); 305 306 /* Tell the I2C layer a new client has arrived */ 307 if ((err = i2c_attach_client(new_client))) 308 goto exit_free; 309 310 /* 311 * Initialize the LM83 chip 312 * (Nothing to do for this one.) 313 */ 314 315 /* Register sysfs hooks */ 316 data->class_dev = hwmon_device_register(&new_client->dev); 317 if (IS_ERR(data->class_dev)) { 318 err = PTR_ERR(data->class_dev); 319 goto exit_detach; 320 } 321 322 device_create_file(&new_client->dev, 323 &sensor_dev_attr_temp1_input.dev_attr); 324 device_create_file(&new_client->dev, 325 &sensor_dev_attr_temp2_input.dev_attr); 326 device_create_file(&new_client->dev, 327 &sensor_dev_attr_temp3_input.dev_attr); 328 device_create_file(&new_client->dev, 329 &sensor_dev_attr_temp4_input.dev_attr); 330 device_create_file(&new_client->dev, 331 &sensor_dev_attr_temp1_max.dev_attr); 332 device_create_file(&new_client->dev, 333 &sensor_dev_attr_temp2_max.dev_attr); 334 device_create_file(&new_client->dev, 335 &sensor_dev_attr_temp3_max.dev_attr); 336 device_create_file(&new_client->dev, 337 &sensor_dev_attr_temp4_max.dev_attr); 338 device_create_file(&new_client->dev, 339 &sensor_dev_attr_temp1_crit.dev_attr); 340 device_create_file(&new_client->dev, 341 &sensor_dev_attr_temp2_crit.dev_attr); 342 device_create_file(&new_client->dev, 343 &sensor_dev_attr_temp3_crit.dev_attr); 344 device_create_file(&new_client->dev, 345 &sensor_dev_attr_temp4_crit.dev_attr); 346 device_create_file(&new_client->dev, &dev_attr_alarms); 347 348 return 0; 349 350 exit_detach: 351 i2c_detach_client(new_client); 352 exit_free: 353 kfree(data); 354 exit: 355 return err; 356 } 357 358 static int lm83_detach_client(struct i2c_client *client) 359 { 360 struct lm83_data *data = i2c_get_clientdata(client); 361 int err; 362 363 hwmon_device_unregister(data->class_dev); 364 365 if ((err = i2c_detach_client(client))) 366 return err; 367 368 kfree(data); 369 return 0; 370 } 371 372 static struct lm83_data *lm83_update_device(struct device *dev) 373 { 374 struct i2c_client *client = to_i2c_client(dev); 375 struct lm83_data *data = i2c_get_clientdata(client); 376 377 down(&data->update_lock); 378 379 if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) { 380 int nr; 381 382 dev_dbg(&client->dev, "Updating lm83 data.\n"); 383 for (nr = 0; nr < 9; nr++) { 384 data->temp[nr] = 385 i2c_smbus_read_byte_data(client, 386 LM83_REG_R_TEMP[nr]); 387 } 388 data->alarms = 389 i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1) 390 + (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2) 391 << 8); 392 393 data->last_updated = jiffies; 394 data->valid = 1; 395 } 396 397 up(&data->update_lock); 398 399 return data; 400 } 401 402 static int __init sensors_lm83_init(void) 403 { 404 return i2c_add_driver(&lm83_driver); 405 } 406 407 static void __exit sensors_lm83_exit(void) 408 { 409 i2c_del_driver(&lm83_driver); 410 } 411 412 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>"); 413 MODULE_DESCRIPTION("LM83 driver"); 414 MODULE_LICENSE("GPL"); 415 416 module_init(sensors_lm83_init); 417 module_exit(sensors_lm83_exit); 418