1 /* 2 * jc42.c - driver for Jedec JC42.4 compliant temperature sensors 3 * 4 * Copyright (c) 2010 Ericsson AB. 5 * 6 * Derived from lm77.c by Andras BALI <drewie@freemail.hu>. 7 * 8 * JC42.4 compliant temperature sensors are typically used on memory modules. 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License as published by 12 * the Free Software Foundation; either version 2 of the License, or 13 * (at your option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 * GNU General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public License 21 * along with this program; if not, write to the Free Software 22 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 23 */ 24 25 #include <linux/module.h> 26 #include <linux/init.h> 27 #include <linux/slab.h> 28 #include <linux/jiffies.h> 29 #include <linux/i2c.h> 30 #include <linux/hwmon.h> 31 #include <linux/hwmon-sysfs.h> 32 #include <linux/err.h> 33 #include <linux/mutex.h> 34 35 /* Addresses to scan */ 36 static const unsigned short normal_i2c[] = { 37 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, I2C_CLIENT_END }; 38 39 /* JC42 registers. All registers are 16 bit. */ 40 #define JC42_REG_CAP 0x00 41 #define JC42_REG_CONFIG 0x01 42 #define JC42_REG_TEMP_UPPER 0x02 43 #define JC42_REG_TEMP_LOWER 0x03 44 #define JC42_REG_TEMP_CRITICAL 0x04 45 #define JC42_REG_TEMP 0x05 46 #define JC42_REG_MANID 0x06 47 #define JC42_REG_DEVICEID 0x07 48 49 /* Status bits in temperature register */ 50 #define JC42_ALARM_CRIT_BIT 15 51 #define JC42_ALARM_MAX_BIT 14 52 #define JC42_ALARM_MIN_BIT 13 53 54 /* Configuration register defines */ 55 #define JC42_CFG_CRIT_ONLY (1 << 2) 56 #define JC42_CFG_TCRIT_LOCK (1 << 6) 57 #define JC42_CFG_EVENT_LOCK (1 << 7) 58 #define JC42_CFG_SHUTDOWN (1 << 8) 59 #define JC42_CFG_HYST_SHIFT 9 60 #define JC42_CFG_HYST_MASK (0x03 << 9) 61 62 /* Capabilities */ 63 #define JC42_CAP_RANGE (1 << 2) 64 65 /* Manufacturer IDs */ 66 #define ADT_MANID 0x11d4 /* Analog Devices */ 67 #define ATMEL_MANID 0x001f /* Atmel */ 68 #define ATMEL_MANID2 0x1114 /* Atmel */ 69 #define MAX_MANID 0x004d /* Maxim */ 70 #define IDT_MANID 0x00b3 /* IDT */ 71 #define MCP_MANID 0x0054 /* Microchip */ 72 #define NXP_MANID 0x1131 /* NXP Semiconductors */ 73 #define ONS_MANID 0x1b09 /* ON Semiconductor */ 74 #define STM_MANID 0x104a /* ST Microelectronics */ 75 76 /* Supported chips */ 77 78 /* Analog Devices */ 79 #define ADT7408_DEVID 0x0801 80 #define ADT7408_DEVID_MASK 0xffff 81 82 /* Atmel */ 83 #define AT30TS00_DEVID 0x8201 84 #define AT30TS00_DEVID_MASK 0xffff 85 86 #define AT30TSE004_DEVID 0x2200 87 #define AT30TSE004_DEVID_MASK 0xffff 88 89 /* IDT */ 90 #define TS3000B3_DEVID 0x2903 /* Also matches TSE2002B3 */ 91 #define TS3000B3_DEVID_MASK 0xffff 92 93 #define TS3000GB2_DEVID 0x2912 /* Also matches TSE2002GB2 */ 94 #define TS3000GB2_DEVID_MASK 0xffff 95 96 /* Maxim */ 97 #define MAX6604_DEVID 0x3e00 98 #define MAX6604_DEVID_MASK 0xffff 99 100 /* Microchip */ 101 #define MCP9804_DEVID 0x0200 102 #define MCP9804_DEVID_MASK 0xfffc 103 104 #define MCP98242_DEVID 0x2000 105 #define MCP98242_DEVID_MASK 0xfffc 106 107 #define MCP98243_DEVID 0x2100 108 #define MCP98243_DEVID_MASK 0xfffc 109 110 #define MCP98244_DEVID 0x2200 111 #define MCP98244_DEVID_MASK 0xfffc 112 113 #define MCP9843_DEVID 0x0000 /* Also matches mcp9805 */ 114 #define MCP9843_DEVID_MASK 0xfffe 115 116 /* NXP */ 117 #define SE97_DEVID 0xa200 118 #define SE97_DEVID_MASK 0xfffc 119 120 #define SE98_DEVID 0xa100 121 #define SE98_DEVID_MASK 0xfffc 122 123 /* ON Semiconductor */ 124 #define CAT6095_DEVID 0x0800 /* Also matches CAT34TS02 */ 125 #define CAT6095_DEVID_MASK 0xffe0 126 127 /* ST Microelectronics */ 128 #define STTS424_DEVID 0x0101 129 #define STTS424_DEVID_MASK 0xffff 130 131 #define STTS424E_DEVID 0x0000 132 #define STTS424E_DEVID_MASK 0xfffe 133 134 #define STTS2002_DEVID 0x0300 135 #define STTS2002_DEVID_MASK 0xffff 136 137 #define STTS2004_DEVID 0x2201 138 #define STTS2004_DEVID_MASK 0xffff 139 140 #define STTS3000_DEVID 0x0200 141 #define STTS3000_DEVID_MASK 0xffff 142 143 static u16 jc42_hysteresis[] = { 0, 1500, 3000, 6000 }; 144 145 struct jc42_chips { 146 u16 manid; 147 u16 devid; 148 u16 devid_mask; 149 }; 150 151 static struct jc42_chips jc42_chips[] = { 152 { ADT_MANID, ADT7408_DEVID, ADT7408_DEVID_MASK }, 153 { ATMEL_MANID, AT30TS00_DEVID, AT30TS00_DEVID_MASK }, 154 { ATMEL_MANID2, AT30TSE004_DEVID, AT30TSE004_DEVID_MASK }, 155 { IDT_MANID, TS3000B3_DEVID, TS3000B3_DEVID_MASK }, 156 { IDT_MANID, TS3000GB2_DEVID, TS3000GB2_DEVID_MASK }, 157 { MAX_MANID, MAX6604_DEVID, MAX6604_DEVID_MASK }, 158 { MCP_MANID, MCP9804_DEVID, MCP9804_DEVID_MASK }, 159 { MCP_MANID, MCP98242_DEVID, MCP98242_DEVID_MASK }, 160 { MCP_MANID, MCP98243_DEVID, MCP98243_DEVID_MASK }, 161 { MCP_MANID, MCP98244_DEVID, MCP98244_DEVID_MASK }, 162 { MCP_MANID, MCP9843_DEVID, MCP9843_DEVID_MASK }, 163 { NXP_MANID, SE97_DEVID, SE97_DEVID_MASK }, 164 { ONS_MANID, CAT6095_DEVID, CAT6095_DEVID_MASK }, 165 { NXP_MANID, SE98_DEVID, SE98_DEVID_MASK }, 166 { STM_MANID, STTS424_DEVID, STTS424_DEVID_MASK }, 167 { STM_MANID, STTS424E_DEVID, STTS424E_DEVID_MASK }, 168 { STM_MANID, STTS2002_DEVID, STTS2002_DEVID_MASK }, 169 { STM_MANID, STTS2004_DEVID, STTS2004_DEVID_MASK }, 170 { STM_MANID, STTS3000_DEVID, STTS3000_DEVID_MASK }, 171 }; 172 173 enum temp_index { 174 t_input = 0, 175 t_crit, 176 t_min, 177 t_max, 178 t_num_temp 179 }; 180 181 static const u8 temp_regs[t_num_temp] = { 182 [t_input] = JC42_REG_TEMP, 183 [t_crit] = JC42_REG_TEMP_CRITICAL, 184 [t_min] = JC42_REG_TEMP_LOWER, 185 [t_max] = JC42_REG_TEMP_UPPER, 186 }; 187 188 /* Each client has this additional data */ 189 struct jc42_data { 190 struct i2c_client *client; 191 struct mutex update_lock; /* protect register access */ 192 bool extended; /* true if extended range supported */ 193 bool valid; 194 unsigned long last_updated; /* In jiffies */ 195 u16 orig_config; /* original configuration */ 196 u16 config; /* current configuration */ 197 u16 temp[t_num_temp];/* Temperatures */ 198 }; 199 200 #define JC42_TEMP_MIN_EXTENDED (-40000) 201 #define JC42_TEMP_MIN 0 202 #define JC42_TEMP_MAX 125000 203 204 static u16 jc42_temp_to_reg(int temp, bool extended) 205 { 206 int ntemp = clamp_val(temp, 207 extended ? JC42_TEMP_MIN_EXTENDED : 208 JC42_TEMP_MIN, JC42_TEMP_MAX); 209 210 /* convert from 0.001 to 0.0625 resolution */ 211 return (ntemp * 2 / 125) & 0x1fff; 212 } 213 214 static int jc42_temp_from_reg(s16 reg) 215 { 216 reg &= 0x1fff; 217 218 /* sign extend register */ 219 if (reg & 0x1000) 220 reg |= 0xf000; 221 222 /* convert from 0.0625 to 0.001 resolution */ 223 return reg * 125 / 2; 224 } 225 226 static struct jc42_data *jc42_update_device(struct device *dev) 227 { 228 struct jc42_data *data = dev_get_drvdata(dev); 229 struct i2c_client *client = data->client; 230 struct jc42_data *ret = data; 231 int i, val; 232 233 mutex_lock(&data->update_lock); 234 235 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) { 236 for (i = 0; i < t_num_temp; i++) { 237 val = i2c_smbus_read_word_swapped(client, temp_regs[i]); 238 if (val < 0) { 239 ret = ERR_PTR(val); 240 goto abort; 241 } 242 data->temp[i] = val; 243 } 244 data->last_updated = jiffies; 245 data->valid = true; 246 } 247 abort: 248 mutex_unlock(&data->update_lock); 249 return ret; 250 } 251 252 /* sysfs functions */ 253 254 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, 255 char *buf) 256 { 257 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 258 struct jc42_data *data = jc42_update_device(dev); 259 if (IS_ERR(data)) 260 return PTR_ERR(data); 261 return sprintf(buf, "%d\n", 262 jc42_temp_from_reg(data->temp[attr->index])); 263 } 264 265 static ssize_t show_temp_hyst(struct device *dev, 266 struct device_attribute *devattr, char *buf) 267 { 268 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 269 struct jc42_data *data = jc42_update_device(dev); 270 int temp, hyst; 271 272 if (IS_ERR(data)) 273 return PTR_ERR(data); 274 275 temp = jc42_temp_from_reg(data->temp[attr->index]); 276 hyst = jc42_hysteresis[(data->config & JC42_CFG_HYST_MASK) 277 >> JC42_CFG_HYST_SHIFT]; 278 return sprintf(buf, "%d\n", temp - hyst); 279 } 280 281 static ssize_t set_temp(struct device *dev, struct device_attribute *devattr, 282 const char *buf, size_t count) 283 { 284 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 285 struct jc42_data *data = dev_get_drvdata(dev); 286 int err, ret = count; 287 int nr = attr->index; 288 long val; 289 290 if (kstrtol(buf, 10, &val) < 0) 291 return -EINVAL; 292 mutex_lock(&data->update_lock); 293 data->temp[nr] = jc42_temp_to_reg(val, data->extended); 294 err = i2c_smbus_write_word_swapped(data->client, temp_regs[nr], 295 data->temp[nr]); 296 if (err < 0) 297 ret = err; 298 mutex_unlock(&data->update_lock); 299 return ret; 300 } 301 302 /* 303 * JC42.4 compliant chips only support four hysteresis values. 304 * Pick best choice and go from there. 305 */ 306 static ssize_t set_temp_crit_hyst(struct device *dev, 307 struct device_attribute *attr, 308 const char *buf, size_t count) 309 { 310 struct jc42_data *data = dev_get_drvdata(dev); 311 unsigned long val; 312 int diff, hyst; 313 int err; 314 int ret = count; 315 316 if (kstrtoul(buf, 10, &val) < 0) 317 return -EINVAL; 318 319 diff = jc42_temp_from_reg(data->temp[t_crit]) - val; 320 hyst = 0; 321 if (diff > 0) { 322 if (diff < 2250) 323 hyst = 1; /* 1.5 degrees C */ 324 else if (diff < 4500) 325 hyst = 2; /* 3.0 degrees C */ 326 else 327 hyst = 3; /* 6.0 degrees C */ 328 } 329 330 mutex_lock(&data->update_lock); 331 data->config = (data->config & ~JC42_CFG_HYST_MASK) 332 | (hyst << JC42_CFG_HYST_SHIFT); 333 err = i2c_smbus_write_word_swapped(data->client, JC42_REG_CONFIG, 334 data->config); 335 if (err < 0) 336 ret = err; 337 mutex_unlock(&data->update_lock); 338 return ret; 339 } 340 341 static ssize_t show_alarm(struct device *dev, 342 struct device_attribute *attr, char *buf) 343 { 344 u16 bit = to_sensor_dev_attr(attr)->index; 345 struct jc42_data *data = jc42_update_device(dev); 346 u16 val; 347 348 if (IS_ERR(data)) 349 return PTR_ERR(data); 350 351 val = data->temp[t_input]; 352 if (bit != JC42_ALARM_CRIT_BIT && (data->config & JC42_CFG_CRIT_ONLY)) 353 val = 0; 354 return sprintf(buf, "%u\n", (val >> bit) & 1); 355 } 356 357 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, t_input); 358 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, set_temp, t_crit); 359 static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO, show_temp, set_temp, t_min); 360 static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp, set_temp, t_max); 361 362 static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IRUGO, show_temp_hyst, 363 set_temp_crit_hyst, t_crit); 364 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IRUGO, show_temp_hyst, NULL, t_max); 365 366 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 367 JC42_ALARM_CRIT_BIT); 368 static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 369 JC42_ALARM_MIN_BIT); 370 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 371 JC42_ALARM_MAX_BIT); 372 373 static struct attribute *jc42_attributes[] = { 374 &sensor_dev_attr_temp1_input.dev_attr.attr, 375 &sensor_dev_attr_temp1_crit.dev_attr.attr, 376 &sensor_dev_attr_temp1_min.dev_attr.attr, 377 &sensor_dev_attr_temp1_max.dev_attr.attr, 378 &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr, 379 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 380 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, 381 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr, 382 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, 383 NULL 384 }; 385 386 static umode_t jc42_attribute_mode(struct kobject *kobj, 387 struct attribute *attr, int index) 388 { 389 struct device *dev = container_of(kobj, struct device, kobj); 390 struct jc42_data *data = dev_get_drvdata(dev); 391 unsigned int config = data->config; 392 bool readonly; 393 394 if (attr == &sensor_dev_attr_temp1_crit.dev_attr.attr) 395 readonly = config & JC42_CFG_TCRIT_LOCK; 396 else if (attr == &sensor_dev_attr_temp1_min.dev_attr.attr || 397 attr == &sensor_dev_attr_temp1_max.dev_attr.attr) 398 readonly = config & JC42_CFG_EVENT_LOCK; 399 else if (attr == &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr) 400 readonly = config & (JC42_CFG_EVENT_LOCK | JC42_CFG_TCRIT_LOCK); 401 else 402 readonly = true; 403 404 return S_IRUGO | (readonly ? 0 : S_IWUSR); 405 } 406 407 static const struct attribute_group jc42_group = { 408 .attrs = jc42_attributes, 409 .is_visible = jc42_attribute_mode, 410 }; 411 __ATTRIBUTE_GROUPS(jc42); 412 413 /* Return 0 if detection is successful, -ENODEV otherwise */ 414 static int jc42_detect(struct i2c_client *client, struct i2c_board_info *info) 415 { 416 struct i2c_adapter *adapter = client->adapter; 417 int i, config, cap, manid, devid; 418 419 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | 420 I2C_FUNC_SMBUS_WORD_DATA)) 421 return -ENODEV; 422 423 cap = i2c_smbus_read_word_swapped(client, JC42_REG_CAP); 424 config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG); 425 manid = i2c_smbus_read_word_swapped(client, JC42_REG_MANID); 426 devid = i2c_smbus_read_word_swapped(client, JC42_REG_DEVICEID); 427 428 if (cap < 0 || config < 0 || manid < 0 || devid < 0) 429 return -ENODEV; 430 431 if ((cap & 0xff00) || (config & 0xf800)) 432 return -ENODEV; 433 434 for (i = 0; i < ARRAY_SIZE(jc42_chips); i++) { 435 struct jc42_chips *chip = &jc42_chips[i]; 436 if (manid == chip->manid && 437 (devid & chip->devid_mask) == chip->devid) { 438 strlcpy(info->type, "jc42", I2C_NAME_SIZE); 439 return 0; 440 } 441 } 442 return -ENODEV; 443 } 444 445 static int jc42_probe(struct i2c_client *client, const struct i2c_device_id *id) 446 { 447 struct device *dev = &client->dev; 448 struct device *hwmon_dev; 449 struct jc42_data *data; 450 int config, cap; 451 452 data = devm_kzalloc(dev, sizeof(struct jc42_data), GFP_KERNEL); 453 if (!data) 454 return -ENOMEM; 455 456 data->client = client; 457 i2c_set_clientdata(client, data); 458 mutex_init(&data->update_lock); 459 460 cap = i2c_smbus_read_word_swapped(client, JC42_REG_CAP); 461 if (cap < 0) 462 return cap; 463 464 data->extended = !!(cap & JC42_CAP_RANGE); 465 466 config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG); 467 if (config < 0) 468 return config; 469 470 data->orig_config = config; 471 if (config & JC42_CFG_SHUTDOWN) { 472 config &= ~JC42_CFG_SHUTDOWN; 473 i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, config); 474 } 475 data->config = config; 476 477 hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, 478 data, 479 jc42_groups); 480 return PTR_ERR_OR_ZERO(hwmon_dev); 481 } 482 483 static int jc42_remove(struct i2c_client *client) 484 { 485 struct jc42_data *data = i2c_get_clientdata(client); 486 487 /* Restore original configuration except hysteresis */ 488 if ((data->config & ~JC42_CFG_HYST_MASK) != 489 (data->orig_config & ~JC42_CFG_HYST_MASK)) { 490 int config; 491 492 config = (data->orig_config & ~JC42_CFG_HYST_MASK) 493 | (data->config & JC42_CFG_HYST_MASK); 494 i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, config); 495 } 496 return 0; 497 } 498 499 #ifdef CONFIG_PM 500 501 static int jc42_suspend(struct device *dev) 502 { 503 struct jc42_data *data = dev_get_drvdata(dev); 504 505 data->config |= JC42_CFG_SHUTDOWN; 506 i2c_smbus_write_word_swapped(data->client, JC42_REG_CONFIG, 507 data->config); 508 return 0; 509 } 510 511 static int jc42_resume(struct device *dev) 512 { 513 struct jc42_data *data = dev_get_drvdata(dev); 514 515 data->config &= ~JC42_CFG_SHUTDOWN; 516 i2c_smbus_write_word_swapped(data->client, JC42_REG_CONFIG, 517 data->config); 518 return 0; 519 } 520 521 static const struct dev_pm_ops jc42_dev_pm_ops = { 522 .suspend = jc42_suspend, 523 .resume = jc42_resume, 524 }; 525 526 #define JC42_DEV_PM_OPS (&jc42_dev_pm_ops) 527 #else 528 #define JC42_DEV_PM_OPS NULL 529 #endif /* CONFIG_PM */ 530 531 static const struct i2c_device_id jc42_id[] = { 532 { "jc42", 0 }, 533 { } 534 }; 535 MODULE_DEVICE_TABLE(i2c, jc42_id); 536 537 static struct i2c_driver jc42_driver = { 538 .class = I2C_CLASS_SPD, 539 .driver = { 540 .name = "jc42", 541 .pm = JC42_DEV_PM_OPS, 542 }, 543 .probe = jc42_probe, 544 .remove = jc42_remove, 545 .id_table = jc42_id, 546 .detect = jc42_detect, 547 .address_list = normal_i2c, 548 }; 549 550 module_i2c_driver(jc42_driver); 551 552 MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>"); 553 MODULE_DESCRIPTION("JC42 driver"); 554 MODULE_LICENSE("GPL"); 555