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/i2c-sensor.h> 36 #include <linux/hwmon-sysfs.h> 37 38 /* 39 * Addresses to scan 40 * Address is selected using 2 three-level pins, resulting in 9 possible 41 * addresses. 42 */ 43 44 static unsigned short normal_i2c[] = { 0x18, 0x19, 0x1a, 45 0x29, 0x2a, 0x2b, 46 0x4c, 0x4d, 0x4e, 47 I2C_CLIENT_END }; 48 static unsigned int normal_isa[] = { I2C_CLIENT_ISA_END }; 49 50 /* 51 * Insmod parameters 52 */ 53 54 SENSORS_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 semaphore update_lock; 142 char valid; /* zero until following fields are valid */ 143 unsigned long last_updated; /* in jiffies */ 144 145 /* registers values */ 146 s8 temp[9]; /* 0..3: input 1-4, 147 4..7: high limit 1-4, 148 8 : critical limit */ 149 u16 alarms; /* bitvector, combined */ 150 }; 151 152 /* 153 * Sysfs stuff 154 */ 155 156 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, 157 char *buf) 158 { 159 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 160 struct lm83_data *data = lm83_update_device(dev); 161 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index])); 162 } 163 164 static ssize_t set_temp(struct device *dev, struct device_attribute *devattr, 165 const char *buf, size_t count) 166 { 167 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 168 struct i2c_client *client = to_i2c_client(dev); 169 struct lm83_data *data = i2c_get_clientdata(client); 170 long val = simple_strtol(buf, NULL, 10); 171 int nr = attr->index; 172 173 down(&data->update_lock); 174 data->temp[nr] = TEMP_TO_REG(val); 175 i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr - 4], 176 data->temp[nr]); 177 up(&data->update_lock); 178 return count; 179 } 180 181 static ssize_t show_alarms(struct device *dev, struct device_attribute *dummy, 182 char *buf) 183 { 184 struct lm83_data *data = lm83_update_device(dev); 185 return sprintf(buf, "%d\n", data->alarms); 186 } 187 188 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0); 189 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1); 190 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2); 191 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3); 192 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp, 193 set_temp, 4); 194 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp, 195 set_temp, 5); 196 static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_temp, 197 set_temp, 6); 198 static SENSOR_DEVICE_ATTR(temp4_max, S_IWUSR | S_IRUGO, show_temp, 199 set_temp, 7); 200 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, 8); 201 static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO, show_temp, NULL, 8); 202 static SENSOR_DEVICE_ATTR(temp3_crit, S_IWUSR | S_IRUGO, show_temp, 203 set_temp, 8); 204 static SENSOR_DEVICE_ATTR(temp4_crit, S_IRUGO, show_temp, NULL, 8); 205 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL); 206 207 /* 208 * Real code 209 */ 210 211 static int lm83_attach_adapter(struct i2c_adapter *adapter) 212 { 213 if (!(adapter->class & I2C_CLASS_HWMON)) 214 return 0; 215 return i2c_detect(adapter, &addr_data, lm83_detect); 216 } 217 218 /* 219 * The following function does more than just detection. If detection 220 * succeeds, it also registers the new chip. 221 */ 222 static int lm83_detect(struct i2c_adapter *adapter, int address, int kind) 223 { 224 struct i2c_client *new_client; 225 struct lm83_data *data; 226 int err = 0; 227 const char *name = ""; 228 229 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 230 goto exit; 231 232 if (!(data = kmalloc(sizeof(struct lm83_data), GFP_KERNEL))) { 233 err = -ENOMEM; 234 goto exit; 235 } 236 memset(data, 0, sizeof(struct lm83_data)); 237 238 /* The common I2C client data is placed right after the 239 * LM83-specific data. */ 240 new_client = &data->client; 241 i2c_set_clientdata(new_client, data); 242 new_client->addr = address; 243 new_client->adapter = adapter; 244 new_client->driver = &lm83_driver; 245 new_client->flags = 0; 246 247 /* Now we do the detection and identification. A negative kind 248 * means that the driver was loaded with no force parameter 249 * (default), so we must both detect and identify the chip 250 * (actually there is only one possible kind of chip for now, LM83). 251 * A zero kind means that the driver was loaded with the force 252 * parameter, the detection step shall be skipped. A positive kind 253 * means that the driver was loaded with the force parameter and a 254 * given kind of chip is requested, so both the detection and the 255 * identification steps are skipped. */ 256 257 /* Default to an LM83 if forced */ 258 if (kind == 0) 259 kind = lm83; 260 261 if (kind < 0) { /* detection */ 262 if (((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1) 263 & 0xA8) != 0x00) || 264 ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2) 265 & 0x48) != 0x00) || 266 ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG) 267 & 0x41) != 0x00)) { 268 dev_dbg(&adapter->dev, 269 "LM83 detection failed at 0x%02x.\n", address); 270 goto exit_free; 271 } 272 } 273 274 if (kind <= 0) { /* identification */ 275 u8 man_id, chip_id; 276 277 man_id = i2c_smbus_read_byte_data(new_client, 278 LM83_REG_R_MAN_ID); 279 chip_id = i2c_smbus_read_byte_data(new_client, 280 LM83_REG_R_CHIP_ID); 281 282 if (man_id == 0x01) { /* National Semiconductor */ 283 if (chip_id == 0x03) { 284 kind = lm83; 285 } 286 } 287 288 if (kind <= 0) { /* identification failed */ 289 dev_info(&adapter->dev, 290 "Unsupported chip (man_id=0x%02X, " 291 "chip_id=0x%02X).\n", man_id, chip_id); 292 goto exit_free; 293 } 294 } 295 296 if (kind == lm83) { 297 name = "lm83"; 298 } 299 300 /* We can fill in the remaining client fields */ 301 strlcpy(new_client->name, name, I2C_NAME_SIZE); 302 data->valid = 0; 303 init_MUTEX(&data->update_lock); 304 305 /* Tell the I2C layer a new client has arrived */ 306 if ((err = i2c_attach_client(new_client))) 307 goto exit_free; 308 309 /* 310 * Initialize the LM83 chip 311 * (Nothing to do for this one.) 312 */ 313 314 /* Register sysfs hooks */ 315 device_create_file(&new_client->dev, 316 &sensor_dev_attr_temp1_input.dev_attr); 317 device_create_file(&new_client->dev, 318 &sensor_dev_attr_temp2_input.dev_attr); 319 device_create_file(&new_client->dev, 320 &sensor_dev_attr_temp3_input.dev_attr); 321 device_create_file(&new_client->dev, 322 &sensor_dev_attr_temp4_input.dev_attr); 323 device_create_file(&new_client->dev, 324 &sensor_dev_attr_temp1_max.dev_attr); 325 device_create_file(&new_client->dev, 326 &sensor_dev_attr_temp2_max.dev_attr); 327 device_create_file(&new_client->dev, 328 &sensor_dev_attr_temp3_max.dev_attr); 329 device_create_file(&new_client->dev, 330 &sensor_dev_attr_temp4_max.dev_attr); 331 device_create_file(&new_client->dev, 332 &sensor_dev_attr_temp1_crit.dev_attr); 333 device_create_file(&new_client->dev, 334 &sensor_dev_attr_temp2_crit.dev_attr); 335 device_create_file(&new_client->dev, 336 &sensor_dev_attr_temp3_crit.dev_attr); 337 device_create_file(&new_client->dev, 338 &sensor_dev_attr_temp4_crit.dev_attr); 339 device_create_file(&new_client->dev, &dev_attr_alarms); 340 341 return 0; 342 343 exit_free: 344 kfree(data); 345 exit: 346 return err; 347 } 348 349 static int lm83_detach_client(struct i2c_client *client) 350 { 351 int err; 352 353 if ((err = i2c_detach_client(client))) { 354 dev_err(&client->dev, 355 "Client deregistration failed, client not detached.\n"); 356 return err; 357 } 358 359 kfree(i2c_get_clientdata(client)); 360 return 0; 361 } 362 363 static struct lm83_data *lm83_update_device(struct device *dev) 364 { 365 struct i2c_client *client = to_i2c_client(dev); 366 struct lm83_data *data = i2c_get_clientdata(client); 367 368 down(&data->update_lock); 369 370 if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) { 371 int nr; 372 373 dev_dbg(&client->dev, "Updating lm83 data.\n"); 374 for (nr = 0; nr < 9; nr++) { 375 data->temp[nr] = 376 i2c_smbus_read_byte_data(client, 377 LM83_REG_R_TEMP[nr]); 378 } 379 data->alarms = 380 i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1) 381 + (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2) 382 << 8); 383 384 data->last_updated = jiffies; 385 data->valid = 1; 386 } 387 388 up(&data->update_lock); 389 390 return data; 391 } 392 393 static int __init sensors_lm83_init(void) 394 { 395 return i2c_add_driver(&lm83_driver); 396 } 397 398 static void __exit sensors_lm83_exit(void) 399 { 400 i2c_del_driver(&lm83_driver); 401 } 402 403 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>"); 404 MODULE_DESCRIPTION("LM83 driver"); 405 MODULE_LICENSE("GPL"); 406 407 module_init(sensors_lm83_init); 408 module_exit(sensors_lm83_exit); 409