1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * lm83.c - Part of lm_sensors, Linux kernel modules for hardware 4 * monitoring 5 * Copyright (C) 2003-2009 Jean Delvare <jdelvare@suse.de> 6 * 7 * Heavily inspired from the lm78, lm75 and adm1021 drivers. The LM83 is 8 * a sensor chip made by National Semiconductor. It reports up to four 9 * temperatures (its own plus up to three external ones) with a 1 deg 10 * resolution and a 3-4 deg accuracy. Complete datasheet can be obtained 11 * from National's website at: 12 * http://www.national.com/pf/LM/LM83.html 13 * Since the datasheet omits to give the chip stepping code, I give it 14 * here: 0x03 (at register 0xff). 15 * 16 * Also supports the LM82 temp sensor, which is basically a stripped down 17 * model of the LM83. Datasheet is here: 18 * http://www.national.com/pf/LM/LM82.html 19 */ 20 21 #include <linux/module.h> 22 #include <linux/init.h> 23 #include <linux/slab.h> 24 #include <linux/jiffies.h> 25 #include <linux/i2c.h> 26 #include <linux/hwmon-sysfs.h> 27 #include <linux/hwmon.h> 28 #include <linux/err.h> 29 #include <linux/mutex.h> 30 #include <linux/sysfs.h> 31 32 /* 33 * Addresses to scan 34 * Address is selected using 2 three-level pins, resulting in 9 possible 35 * addresses. 36 */ 37 38 static const unsigned short normal_i2c[] = { 39 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END }; 40 41 enum chips { lm83, lm82 }; 42 43 /* 44 * The LM83 registers 45 * Manufacturer ID is 0x01 for National Semiconductor. 46 */ 47 48 #define LM83_REG_R_MAN_ID 0xFE 49 #define LM83_REG_R_CHIP_ID 0xFF 50 #define LM83_REG_R_CONFIG 0x03 51 #define LM83_REG_W_CONFIG 0x09 52 #define LM83_REG_R_STATUS1 0x02 53 #define LM83_REG_R_STATUS2 0x35 54 #define LM83_REG_R_LOCAL_TEMP 0x00 55 #define LM83_REG_R_LOCAL_HIGH 0x05 56 #define LM83_REG_W_LOCAL_HIGH 0x0B 57 #define LM83_REG_R_REMOTE1_TEMP 0x30 58 #define LM83_REG_R_REMOTE1_HIGH 0x38 59 #define LM83_REG_W_REMOTE1_HIGH 0x50 60 #define LM83_REG_R_REMOTE2_TEMP 0x01 61 #define LM83_REG_R_REMOTE2_HIGH 0x07 62 #define LM83_REG_W_REMOTE2_HIGH 0x0D 63 #define LM83_REG_R_REMOTE3_TEMP 0x31 64 #define LM83_REG_R_REMOTE3_HIGH 0x3A 65 #define LM83_REG_W_REMOTE3_HIGH 0x52 66 #define LM83_REG_R_TCRIT 0x42 67 #define LM83_REG_W_TCRIT 0x5A 68 69 /* 70 * Conversions and various macros 71 * The LM83 uses signed 8-bit values with LSB = 1 degree Celsius. 72 */ 73 74 #define TEMP_FROM_REG(val) ((val) * 1000) 75 #define TEMP_TO_REG(val) ((val) <= -128000 ? -128 : \ 76 (val) >= 127000 ? 127 : \ 77 (val) < 0 ? ((val) - 500) / 1000 : \ 78 ((val) + 500) / 1000) 79 80 static const u8 LM83_REG_R_TEMP[] = { 81 LM83_REG_R_LOCAL_TEMP, 82 LM83_REG_R_REMOTE1_TEMP, 83 LM83_REG_R_REMOTE2_TEMP, 84 LM83_REG_R_REMOTE3_TEMP, 85 LM83_REG_R_LOCAL_HIGH, 86 LM83_REG_R_REMOTE1_HIGH, 87 LM83_REG_R_REMOTE2_HIGH, 88 LM83_REG_R_REMOTE3_HIGH, 89 LM83_REG_R_TCRIT, 90 }; 91 92 static const u8 LM83_REG_W_HIGH[] = { 93 LM83_REG_W_LOCAL_HIGH, 94 LM83_REG_W_REMOTE1_HIGH, 95 LM83_REG_W_REMOTE2_HIGH, 96 LM83_REG_W_REMOTE3_HIGH, 97 LM83_REG_W_TCRIT, 98 }; 99 100 /* 101 * Client data (each client gets its own) 102 */ 103 104 struct lm83_data { 105 struct i2c_client *client; 106 const struct attribute_group *groups[3]; 107 struct mutex update_lock; 108 bool valid; /* false until following fields are valid */ 109 unsigned long last_updated; /* in jiffies */ 110 111 /* registers values */ 112 s8 temp[9]; /* 0..3: input 1-4, 113 4..7: high limit 1-4, 114 8 : critical limit */ 115 u16 alarms; /* bitvector, combined */ 116 }; 117 118 static struct lm83_data *lm83_update_device(struct device *dev) 119 { 120 struct lm83_data *data = dev_get_drvdata(dev); 121 struct i2c_client *client = data->client; 122 123 mutex_lock(&data->update_lock); 124 125 if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) { 126 int nr; 127 128 dev_dbg(&client->dev, "Updating lm83 data.\n"); 129 for (nr = 0; nr < 9; nr++) { 130 data->temp[nr] = 131 i2c_smbus_read_byte_data(client, 132 LM83_REG_R_TEMP[nr]); 133 } 134 data->alarms = 135 i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1) 136 + (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2) 137 << 8); 138 139 data->last_updated = jiffies; 140 data->valid = true; 141 } 142 143 mutex_unlock(&data->update_lock); 144 145 return data; 146 } 147 148 /* 149 * Sysfs stuff 150 */ 151 152 static ssize_t temp_show(struct device *dev, struct device_attribute *devattr, 153 char *buf) 154 { 155 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 156 struct lm83_data *data = lm83_update_device(dev); 157 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index])); 158 } 159 160 static ssize_t temp_store(struct device *dev, 161 struct device_attribute *devattr, const char *buf, 162 size_t count) 163 { 164 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 165 struct lm83_data *data = dev_get_drvdata(dev); 166 struct i2c_client *client = data->client; 167 long val; 168 int nr = attr->index; 169 int err; 170 171 err = kstrtol(buf, 10, &val); 172 if (err < 0) 173 return err; 174 175 mutex_lock(&data->update_lock); 176 data->temp[nr] = TEMP_TO_REG(val); 177 i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr - 4], 178 data->temp[nr]); 179 mutex_unlock(&data->update_lock); 180 return count; 181 } 182 183 static ssize_t alarms_show(struct device *dev, struct device_attribute *dummy, 184 char *buf) 185 { 186 struct lm83_data *data = lm83_update_device(dev); 187 return sprintf(buf, "%d\n", data->alarms); 188 } 189 190 static ssize_t alarm_show(struct device *dev, 191 struct device_attribute *devattr, char *buf) 192 { 193 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 194 struct lm83_data *data = lm83_update_device(dev); 195 int bitnr = attr->index; 196 197 return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1); 198 } 199 200 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, 0); 201 static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, 1); 202 static SENSOR_DEVICE_ATTR_RO(temp3_input, temp, 2); 203 static SENSOR_DEVICE_ATTR_RO(temp4_input, temp, 3); 204 static SENSOR_DEVICE_ATTR_RW(temp1_max, temp, 4); 205 static SENSOR_DEVICE_ATTR_RW(temp2_max, temp, 5); 206 static SENSOR_DEVICE_ATTR_RW(temp3_max, temp, 6); 207 static SENSOR_DEVICE_ATTR_RW(temp4_max, temp, 7); 208 static SENSOR_DEVICE_ATTR_RO(temp1_crit, temp, 8); 209 static SENSOR_DEVICE_ATTR_RO(temp2_crit, temp, 8); 210 static SENSOR_DEVICE_ATTR_RW(temp3_crit, temp, 8); 211 static SENSOR_DEVICE_ATTR_RO(temp4_crit, temp, 8); 212 213 /* Individual alarm files */ 214 static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, alarm, 0); 215 static SENSOR_DEVICE_ATTR_RO(temp3_crit_alarm, alarm, 1); 216 static SENSOR_DEVICE_ATTR_RO(temp3_fault, alarm, 2); 217 static SENSOR_DEVICE_ATTR_RO(temp3_max_alarm, alarm, 4); 218 static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, alarm, 6); 219 static SENSOR_DEVICE_ATTR_RO(temp2_crit_alarm, alarm, 8); 220 static SENSOR_DEVICE_ATTR_RO(temp4_crit_alarm, alarm, 9); 221 static SENSOR_DEVICE_ATTR_RO(temp4_fault, alarm, 10); 222 static SENSOR_DEVICE_ATTR_RO(temp4_max_alarm, alarm, 12); 223 static SENSOR_DEVICE_ATTR_RO(temp2_fault, alarm, 13); 224 static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, alarm, 15); 225 /* Raw alarm file for compatibility */ 226 static DEVICE_ATTR_RO(alarms); 227 228 static struct attribute *lm83_attributes[] = { 229 &sensor_dev_attr_temp1_input.dev_attr.attr, 230 &sensor_dev_attr_temp3_input.dev_attr.attr, 231 &sensor_dev_attr_temp1_max.dev_attr.attr, 232 &sensor_dev_attr_temp3_max.dev_attr.attr, 233 &sensor_dev_attr_temp1_crit.dev_attr.attr, 234 &sensor_dev_attr_temp3_crit.dev_attr.attr, 235 236 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, 237 &sensor_dev_attr_temp3_crit_alarm.dev_attr.attr, 238 &sensor_dev_attr_temp3_fault.dev_attr.attr, 239 &sensor_dev_attr_temp3_max_alarm.dev_attr.attr, 240 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, 241 &dev_attr_alarms.attr, 242 NULL 243 }; 244 245 static const struct attribute_group lm83_group = { 246 .attrs = lm83_attributes, 247 }; 248 249 static struct attribute *lm83_attributes_opt[] = { 250 &sensor_dev_attr_temp2_input.dev_attr.attr, 251 &sensor_dev_attr_temp4_input.dev_attr.attr, 252 &sensor_dev_attr_temp2_max.dev_attr.attr, 253 &sensor_dev_attr_temp4_max.dev_attr.attr, 254 &sensor_dev_attr_temp2_crit.dev_attr.attr, 255 &sensor_dev_attr_temp4_crit.dev_attr.attr, 256 257 &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr, 258 &sensor_dev_attr_temp4_crit_alarm.dev_attr.attr, 259 &sensor_dev_attr_temp4_fault.dev_attr.attr, 260 &sensor_dev_attr_temp4_max_alarm.dev_attr.attr, 261 &sensor_dev_attr_temp2_fault.dev_attr.attr, 262 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr, 263 NULL 264 }; 265 266 static const struct attribute_group lm83_group_opt = { 267 .attrs = lm83_attributes_opt, 268 }; 269 270 /* 271 * Real code 272 */ 273 274 /* Return 0 if detection is successful, -ENODEV otherwise */ 275 static int lm83_detect(struct i2c_client *new_client, 276 struct i2c_board_info *info) 277 { 278 struct i2c_adapter *adapter = new_client->adapter; 279 const char *name; 280 u8 man_id, chip_id; 281 282 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 283 return -ENODEV; 284 285 /* Detection */ 286 if ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1) & 0xA8) || 287 (i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2) & 0x48) || 288 (i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG) & 0x41)) { 289 dev_dbg(&adapter->dev, "LM83 detection failed at 0x%02x\n", 290 new_client->addr); 291 return -ENODEV; 292 } 293 294 /* Identification */ 295 man_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_MAN_ID); 296 if (man_id != 0x01) /* National Semiconductor */ 297 return -ENODEV; 298 299 chip_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_CHIP_ID); 300 switch (chip_id) { 301 case 0x03: 302 name = "lm83"; 303 break; 304 case 0x01: 305 name = "lm82"; 306 break; 307 default: 308 /* identification failed */ 309 dev_info(&adapter->dev, 310 "Unsupported chip (man_id=0x%02X, chip_id=0x%02X)\n", 311 man_id, chip_id); 312 return -ENODEV; 313 } 314 315 strlcpy(info->type, name, I2C_NAME_SIZE); 316 317 return 0; 318 } 319 320 static const struct i2c_device_id lm83_id[]; 321 322 static int lm83_probe(struct i2c_client *new_client) 323 { 324 struct device *hwmon_dev; 325 struct lm83_data *data; 326 327 data = devm_kzalloc(&new_client->dev, sizeof(struct lm83_data), 328 GFP_KERNEL); 329 if (!data) 330 return -ENOMEM; 331 332 data->client = new_client; 333 mutex_init(&data->update_lock); 334 335 /* 336 * Register sysfs hooks 337 * The LM82 can only monitor one external diode which is 338 * at the same register as the LM83 temp3 entry - so we 339 * declare 1 and 3 common, and then 2 and 4 only for the LM83. 340 */ 341 data->groups[0] = &lm83_group; 342 if (i2c_match_id(lm83_id, new_client)->driver_data == lm83) 343 data->groups[1] = &lm83_group_opt; 344 345 hwmon_dev = devm_hwmon_device_register_with_groups(&new_client->dev, 346 new_client->name, 347 data, data->groups); 348 return PTR_ERR_OR_ZERO(hwmon_dev); 349 } 350 351 /* 352 * Driver data (common to all clients) 353 */ 354 355 static const struct i2c_device_id lm83_id[] = { 356 { "lm83", lm83 }, 357 { "lm82", lm82 }, 358 { } 359 }; 360 MODULE_DEVICE_TABLE(i2c, lm83_id); 361 362 static struct i2c_driver lm83_driver = { 363 .class = I2C_CLASS_HWMON, 364 .driver = { 365 .name = "lm83", 366 }, 367 .probe_new = lm83_probe, 368 .id_table = lm83_id, 369 .detect = lm83_detect, 370 .address_list = normal_i2c, 371 }; 372 373 module_i2c_driver(lm83_driver); 374 375 MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>"); 376 MODULE_DESCRIPTION("LM83 driver"); 377 MODULE_LICENSE("GPL"); 378