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 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 MAX_MANID 0x004d /* Maxim */ 69 #define IDT_MANID 0x00b3 /* IDT */ 70 #define MCP_MANID 0x0054 /* Microchip */ 71 #define NXP_MANID 0x1131 /* NXP Semiconductors */ 72 #define ONS_MANID 0x1b09 /* ON Semiconductor */ 73 #define STM_MANID 0x104a /* ST Microelectronics */ 74 75 /* Supported chips */ 76 77 /* Analog Devices */ 78 #define ADT7408_DEVID 0x0801 79 #define ADT7408_DEVID_MASK 0xffff 80 81 /* Atmel */ 82 #define AT30TS00_DEVID 0x8201 83 #define AT30TS00_DEVID_MASK 0xffff 84 85 /* IDT */ 86 #define TS3000B3_DEVID 0x2903 /* Also matches TSE2002B3 */ 87 #define TS3000B3_DEVID_MASK 0xffff 88 89 #define TS3000GB2_DEVID 0x2912 /* Also matches TSE2002GB2 */ 90 #define TS3000GB2_DEVID_MASK 0xffff 91 92 /* Maxim */ 93 #define MAX6604_DEVID 0x3e00 94 #define MAX6604_DEVID_MASK 0xffff 95 96 /* Microchip */ 97 #define MCP9804_DEVID 0x0200 98 #define MCP9804_DEVID_MASK 0xfffc 99 100 #define MCP98242_DEVID 0x2000 101 #define MCP98242_DEVID_MASK 0xfffc 102 103 #define MCP98243_DEVID 0x2100 104 #define MCP98243_DEVID_MASK 0xfffc 105 106 #define MCP9843_DEVID 0x0000 /* Also matches mcp9805 */ 107 #define MCP9843_DEVID_MASK 0xfffe 108 109 /* NXP */ 110 #define SE97_DEVID 0xa200 111 #define SE97_DEVID_MASK 0xfffc 112 113 #define SE98_DEVID 0xa100 114 #define SE98_DEVID_MASK 0xfffc 115 116 /* ON Semiconductor */ 117 #define CAT6095_DEVID 0x0800 /* Also matches CAT34TS02 */ 118 #define CAT6095_DEVID_MASK 0xffe0 119 120 /* ST Microelectronics */ 121 #define STTS424_DEVID 0x0101 122 #define STTS424_DEVID_MASK 0xffff 123 124 #define STTS424E_DEVID 0x0000 125 #define STTS424E_DEVID_MASK 0xfffe 126 127 #define STTS2002_DEVID 0x0300 128 #define STTS2002_DEVID_MASK 0xffff 129 130 #define STTS3000_DEVID 0x0200 131 #define STTS3000_DEVID_MASK 0xffff 132 133 static u16 jc42_hysteresis[] = { 0, 1500, 3000, 6000 }; 134 135 struct jc42_chips { 136 u16 manid; 137 u16 devid; 138 u16 devid_mask; 139 }; 140 141 static struct jc42_chips jc42_chips[] = { 142 { ADT_MANID, ADT7408_DEVID, ADT7408_DEVID_MASK }, 143 { ATMEL_MANID, AT30TS00_DEVID, AT30TS00_DEVID_MASK }, 144 { IDT_MANID, TS3000B3_DEVID, TS3000B3_DEVID_MASK }, 145 { IDT_MANID, TS3000GB2_DEVID, TS3000GB2_DEVID_MASK }, 146 { MAX_MANID, MAX6604_DEVID, MAX6604_DEVID_MASK }, 147 { MCP_MANID, MCP9804_DEVID, MCP9804_DEVID_MASK }, 148 { MCP_MANID, MCP98242_DEVID, MCP98242_DEVID_MASK }, 149 { MCP_MANID, MCP98243_DEVID, MCP98243_DEVID_MASK }, 150 { MCP_MANID, MCP9843_DEVID, MCP9843_DEVID_MASK }, 151 { NXP_MANID, SE97_DEVID, SE97_DEVID_MASK }, 152 { ONS_MANID, CAT6095_DEVID, CAT6095_DEVID_MASK }, 153 { NXP_MANID, SE98_DEVID, SE98_DEVID_MASK }, 154 { STM_MANID, STTS424_DEVID, STTS424_DEVID_MASK }, 155 { STM_MANID, STTS424E_DEVID, STTS424E_DEVID_MASK }, 156 { STM_MANID, STTS2002_DEVID, STTS2002_DEVID_MASK }, 157 { STM_MANID, STTS3000_DEVID, STTS3000_DEVID_MASK }, 158 }; 159 160 /* Each client has this additional data */ 161 struct jc42_data { 162 struct device *hwmon_dev; 163 struct mutex update_lock; /* protect register access */ 164 bool extended; /* true if extended range supported */ 165 bool valid; 166 unsigned long last_updated; /* In jiffies */ 167 u16 orig_config; /* original configuration */ 168 u16 config; /* current configuration */ 169 u16 temp_input; /* Temperatures */ 170 u16 temp_crit; 171 u16 temp_min; 172 u16 temp_max; 173 }; 174 175 static int jc42_probe(struct i2c_client *client, 176 const struct i2c_device_id *id); 177 static int jc42_detect(struct i2c_client *client, struct i2c_board_info *info); 178 static int jc42_remove(struct i2c_client *client); 179 180 static struct jc42_data *jc42_update_device(struct device *dev); 181 182 static const struct i2c_device_id jc42_id[] = { 183 { "jc42", 0 }, 184 { } 185 }; 186 MODULE_DEVICE_TABLE(i2c, jc42_id); 187 188 #ifdef CONFIG_PM 189 190 static int jc42_suspend(struct device *dev) 191 { 192 struct i2c_client *client = to_i2c_client(dev); 193 struct jc42_data *data = i2c_get_clientdata(client); 194 195 data->config |= JC42_CFG_SHUTDOWN; 196 i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, data->config); 197 return 0; 198 } 199 200 static int jc42_resume(struct device *dev) 201 { 202 struct i2c_client *client = to_i2c_client(dev); 203 struct jc42_data *data = i2c_get_clientdata(client); 204 205 data->config &= ~JC42_CFG_SHUTDOWN; 206 i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, data->config); 207 return 0; 208 } 209 210 static const struct dev_pm_ops jc42_dev_pm_ops = { 211 .suspend = jc42_suspend, 212 .resume = jc42_resume, 213 }; 214 215 #define JC42_DEV_PM_OPS (&jc42_dev_pm_ops) 216 #else 217 #define JC42_DEV_PM_OPS NULL 218 #endif /* CONFIG_PM */ 219 220 /* This is the driver that will be inserted */ 221 static struct i2c_driver jc42_driver = { 222 .class = I2C_CLASS_SPD, 223 .driver = { 224 .name = "jc42", 225 .pm = JC42_DEV_PM_OPS, 226 }, 227 .probe = jc42_probe, 228 .remove = jc42_remove, 229 .id_table = jc42_id, 230 .detect = jc42_detect, 231 .address_list = normal_i2c, 232 }; 233 234 #define JC42_TEMP_MIN_EXTENDED (-40000) 235 #define JC42_TEMP_MIN 0 236 #define JC42_TEMP_MAX 125000 237 238 static u16 jc42_temp_to_reg(int temp, bool extended) 239 { 240 int ntemp = SENSORS_LIMIT(temp, 241 extended ? JC42_TEMP_MIN_EXTENDED : 242 JC42_TEMP_MIN, JC42_TEMP_MAX); 243 244 /* convert from 0.001 to 0.0625 resolution */ 245 return (ntemp * 2 / 125) & 0x1fff; 246 } 247 248 static int jc42_temp_from_reg(s16 reg) 249 { 250 reg &= 0x1fff; 251 252 /* sign extend register */ 253 if (reg & 0x1000) 254 reg |= 0xf000; 255 256 /* convert from 0.0625 to 0.001 resolution */ 257 return reg * 125 / 2; 258 } 259 260 /* sysfs stuff */ 261 262 /* read routines for temperature limits */ 263 #define show(value) \ 264 static ssize_t show_##value(struct device *dev, \ 265 struct device_attribute *attr, \ 266 char *buf) \ 267 { \ 268 struct jc42_data *data = jc42_update_device(dev); \ 269 if (IS_ERR(data)) \ 270 return PTR_ERR(data); \ 271 return sprintf(buf, "%d\n", jc42_temp_from_reg(data->value)); \ 272 } 273 274 show(temp_input); 275 show(temp_crit); 276 show(temp_min); 277 show(temp_max); 278 279 /* read routines for hysteresis values */ 280 static ssize_t show_temp_crit_hyst(struct device *dev, 281 struct device_attribute *attr, char *buf) 282 { 283 struct jc42_data *data = jc42_update_device(dev); 284 int temp, hyst; 285 286 if (IS_ERR(data)) 287 return PTR_ERR(data); 288 289 temp = jc42_temp_from_reg(data->temp_crit); 290 hyst = jc42_hysteresis[(data->config >> JC42_CFG_HYST_SHIFT) 291 & JC42_CFG_HYST_MASK]; 292 return sprintf(buf, "%d\n", temp - hyst); 293 } 294 295 static ssize_t show_temp_max_hyst(struct device *dev, 296 struct device_attribute *attr, char *buf) 297 { 298 struct jc42_data *data = jc42_update_device(dev); 299 int temp, hyst; 300 301 if (IS_ERR(data)) 302 return PTR_ERR(data); 303 304 temp = jc42_temp_from_reg(data->temp_max); 305 hyst = jc42_hysteresis[(data->config >> JC42_CFG_HYST_SHIFT) 306 & JC42_CFG_HYST_MASK]; 307 return sprintf(buf, "%d\n", temp - hyst); 308 } 309 310 /* write routines */ 311 #define set(value, reg) \ 312 static ssize_t set_##value(struct device *dev, \ 313 struct device_attribute *attr, \ 314 const char *buf, size_t count) \ 315 { \ 316 struct i2c_client *client = to_i2c_client(dev); \ 317 struct jc42_data *data = i2c_get_clientdata(client); \ 318 int err, ret = count; \ 319 long val; \ 320 if (kstrtol(buf, 10, &val) < 0) \ 321 return -EINVAL; \ 322 mutex_lock(&data->update_lock); \ 323 data->value = jc42_temp_to_reg(val, data->extended); \ 324 err = i2c_smbus_write_word_swapped(client, reg, data->value); \ 325 if (err < 0) \ 326 ret = err; \ 327 mutex_unlock(&data->update_lock); \ 328 return ret; \ 329 } 330 331 set(temp_min, JC42_REG_TEMP_LOWER); 332 set(temp_max, JC42_REG_TEMP_UPPER); 333 set(temp_crit, JC42_REG_TEMP_CRITICAL); 334 335 /* 336 * JC42.4 compliant chips only support four hysteresis values. 337 * Pick best choice and go from there. 338 */ 339 static ssize_t set_temp_crit_hyst(struct device *dev, 340 struct device_attribute *attr, 341 const char *buf, size_t count) 342 { 343 struct i2c_client *client = to_i2c_client(dev); 344 struct jc42_data *data = i2c_get_clientdata(client); 345 unsigned long val; 346 int diff, hyst; 347 int err; 348 int ret = count; 349 350 if (kstrtoul(buf, 10, &val) < 0) 351 return -EINVAL; 352 353 diff = jc42_temp_from_reg(data->temp_crit) - val; 354 hyst = 0; 355 if (diff > 0) { 356 if (diff < 2250) 357 hyst = 1; /* 1.5 degrees C */ 358 else if (diff < 4500) 359 hyst = 2; /* 3.0 degrees C */ 360 else 361 hyst = 3; /* 6.0 degrees C */ 362 } 363 364 mutex_lock(&data->update_lock); 365 data->config = (data->config 366 & ~(JC42_CFG_HYST_MASK << JC42_CFG_HYST_SHIFT)) 367 | (hyst << JC42_CFG_HYST_SHIFT); 368 err = i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, 369 data->config); 370 if (err < 0) 371 ret = err; 372 mutex_unlock(&data->update_lock); 373 return ret; 374 } 375 376 static ssize_t show_alarm(struct device *dev, 377 struct device_attribute *attr, char *buf) 378 { 379 u16 bit = to_sensor_dev_attr(attr)->index; 380 struct jc42_data *data = jc42_update_device(dev); 381 u16 val; 382 383 if (IS_ERR(data)) 384 return PTR_ERR(data); 385 386 val = data->temp_input; 387 if (bit != JC42_ALARM_CRIT_BIT && (data->config & JC42_CFG_CRIT_ONLY)) 388 val = 0; 389 return sprintf(buf, "%u\n", (val >> bit) & 1); 390 } 391 392 static DEVICE_ATTR(temp1_input, S_IRUGO, 393 show_temp_input, NULL); 394 static DEVICE_ATTR(temp1_crit, S_IRUGO, 395 show_temp_crit, set_temp_crit); 396 static DEVICE_ATTR(temp1_min, S_IRUGO, 397 show_temp_min, set_temp_min); 398 static DEVICE_ATTR(temp1_max, S_IRUGO, 399 show_temp_max, set_temp_max); 400 401 static DEVICE_ATTR(temp1_crit_hyst, S_IRUGO, 402 show_temp_crit_hyst, set_temp_crit_hyst); 403 static DEVICE_ATTR(temp1_max_hyst, S_IRUGO, 404 show_temp_max_hyst, NULL); 405 406 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 407 JC42_ALARM_CRIT_BIT); 408 static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 409 JC42_ALARM_MIN_BIT); 410 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 411 JC42_ALARM_MAX_BIT); 412 413 static struct attribute *jc42_attributes[] = { 414 &dev_attr_temp1_input.attr, 415 &dev_attr_temp1_crit.attr, 416 &dev_attr_temp1_min.attr, 417 &dev_attr_temp1_max.attr, 418 &dev_attr_temp1_crit_hyst.attr, 419 &dev_attr_temp1_max_hyst.attr, 420 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, 421 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr, 422 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, 423 NULL 424 }; 425 426 static umode_t jc42_attribute_mode(struct kobject *kobj, 427 struct attribute *attr, int index) 428 { 429 struct device *dev = container_of(kobj, struct device, kobj); 430 struct i2c_client *client = to_i2c_client(dev); 431 struct jc42_data *data = i2c_get_clientdata(client); 432 unsigned int config = data->config; 433 bool readonly; 434 435 if (attr == &dev_attr_temp1_crit.attr) 436 readonly = config & JC42_CFG_TCRIT_LOCK; 437 else if (attr == &dev_attr_temp1_min.attr || 438 attr == &dev_attr_temp1_max.attr) 439 readonly = config & JC42_CFG_EVENT_LOCK; 440 else if (attr == &dev_attr_temp1_crit_hyst.attr) 441 readonly = config & (JC42_CFG_EVENT_LOCK | JC42_CFG_TCRIT_LOCK); 442 else 443 readonly = true; 444 445 return S_IRUGO | (readonly ? 0 : S_IWUSR); 446 } 447 448 static const struct attribute_group jc42_group = { 449 .attrs = jc42_attributes, 450 .is_visible = jc42_attribute_mode, 451 }; 452 453 /* Return 0 if detection is successful, -ENODEV otherwise */ 454 static int jc42_detect(struct i2c_client *client, struct i2c_board_info *info) 455 { 456 struct i2c_adapter *adapter = client->adapter; 457 int i, config, cap, manid, devid; 458 459 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | 460 I2C_FUNC_SMBUS_WORD_DATA)) 461 return -ENODEV; 462 463 cap = i2c_smbus_read_word_swapped(client, JC42_REG_CAP); 464 config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG); 465 manid = i2c_smbus_read_word_swapped(client, JC42_REG_MANID); 466 devid = i2c_smbus_read_word_swapped(client, JC42_REG_DEVICEID); 467 468 if (cap < 0 || config < 0 || manid < 0 || devid < 0) 469 return -ENODEV; 470 471 if ((cap & 0xff00) || (config & 0xf800)) 472 return -ENODEV; 473 474 for (i = 0; i < ARRAY_SIZE(jc42_chips); i++) { 475 struct jc42_chips *chip = &jc42_chips[i]; 476 if (manid == chip->manid && 477 (devid & chip->devid_mask) == chip->devid) { 478 strlcpy(info->type, "jc42", I2C_NAME_SIZE); 479 return 0; 480 } 481 } 482 return -ENODEV; 483 } 484 485 static int jc42_probe(struct i2c_client *client, const struct i2c_device_id *id) 486 { 487 struct jc42_data *data; 488 int config, cap, err; 489 struct device *dev = &client->dev; 490 491 data = devm_kzalloc(dev, sizeof(struct jc42_data), GFP_KERNEL); 492 if (!data) 493 return -ENOMEM; 494 495 i2c_set_clientdata(client, data); 496 mutex_init(&data->update_lock); 497 498 cap = i2c_smbus_read_word_swapped(client, JC42_REG_CAP); 499 if (cap < 0) 500 return cap; 501 502 data->extended = !!(cap & JC42_CAP_RANGE); 503 504 config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG); 505 if (config < 0) 506 return config; 507 508 data->orig_config = config; 509 if (config & JC42_CFG_SHUTDOWN) { 510 config &= ~JC42_CFG_SHUTDOWN; 511 i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, config); 512 } 513 data->config = config; 514 515 /* Register sysfs hooks */ 516 err = sysfs_create_group(&dev->kobj, &jc42_group); 517 if (err) 518 return err; 519 520 data->hwmon_dev = hwmon_device_register(dev); 521 if (IS_ERR(data->hwmon_dev)) { 522 err = PTR_ERR(data->hwmon_dev); 523 goto exit_remove; 524 } 525 526 return 0; 527 528 exit_remove: 529 sysfs_remove_group(&dev->kobj, &jc42_group); 530 return err; 531 } 532 533 static int jc42_remove(struct i2c_client *client) 534 { 535 struct jc42_data *data = i2c_get_clientdata(client); 536 hwmon_device_unregister(data->hwmon_dev); 537 sysfs_remove_group(&client->dev.kobj, &jc42_group); 538 if (data->config != data->orig_config) 539 i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, 540 data->orig_config); 541 return 0; 542 } 543 544 static struct jc42_data *jc42_update_device(struct device *dev) 545 { 546 struct i2c_client *client = to_i2c_client(dev); 547 struct jc42_data *data = i2c_get_clientdata(client); 548 struct jc42_data *ret = data; 549 int val; 550 551 mutex_lock(&data->update_lock); 552 553 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) { 554 val = i2c_smbus_read_word_swapped(client, JC42_REG_TEMP); 555 if (val < 0) { 556 ret = ERR_PTR(val); 557 goto abort; 558 } 559 data->temp_input = val; 560 561 val = i2c_smbus_read_word_swapped(client, 562 JC42_REG_TEMP_CRITICAL); 563 if (val < 0) { 564 ret = ERR_PTR(val); 565 goto abort; 566 } 567 data->temp_crit = val; 568 569 val = i2c_smbus_read_word_swapped(client, JC42_REG_TEMP_LOWER); 570 if (val < 0) { 571 ret = ERR_PTR(val); 572 goto abort; 573 } 574 data->temp_min = val; 575 576 val = i2c_smbus_read_word_swapped(client, JC42_REG_TEMP_UPPER); 577 if (val < 0) { 578 ret = ERR_PTR(val); 579 goto abort; 580 } 581 data->temp_max = val; 582 583 data->last_updated = jiffies; 584 data->valid = true; 585 } 586 abort: 587 mutex_unlock(&data->update_lock); 588 return ret; 589 } 590 591 module_i2c_driver(jc42_driver); 592 593 MODULE_AUTHOR("Guenter Roeck <guenter.roeck@ericsson.com>"); 594 MODULE_DESCRIPTION("JC42 driver"); 595 MODULE_LICENSE("GPL"); 596