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 TSE2004_DEVID 0x2200 91 #define TSE2004_DEVID_MASK 0xff00 92 93 #define TS3000_DEVID 0x2900 /* Also matches TSE2002 */ 94 #define TS3000_DEVID_MASK 0xff00 95 96 #define TS3001_DEVID 0x3000 97 #define TS3001_DEVID_MASK 0xff00 98 99 /* Maxim */ 100 #define MAX6604_DEVID 0x3e00 101 #define MAX6604_DEVID_MASK 0xffff 102 103 /* Microchip */ 104 #define MCP9804_DEVID 0x0200 105 #define MCP9804_DEVID_MASK 0xfffc 106 107 #define MCP98242_DEVID 0x2000 108 #define MCP98242_DEVID_MASK 0xfffc 109 110 #define MCP98243_DEVID 0x2100 111 #define MCP98243_DEVID_MASK 0xfffc 112 113 #define MCP98244_DEVID 0x2200 114 #define MCP98244_DEVID_MASK 0xfffc 115 116 #define MCP9843_DEVID 0x0000 /* Also matches mcp9805 */ 117 #define MCP9843_DEVID_MASK 0xfffe 118 119 /* NXP */ 120 #define SE97_DEVID 0xa200 121 #define SE97_DEVID_MASK 0xfffc 122 123 #define SE98_DEVID 0xa100 124 #define SE98_DEVID_MASK 0xfffc 125 126 /* ON Semiconductor */ 127 #define CAT6095_DEVID 0x0800 /* Also matches CAT34TS02 */ 128 #define CAT6095_DEVID_MASK 0xffe0 129 130 /* ST Microelectronics */ 131 #define STTS424_DEVID 0x0101 132 #define STTS424_DEVID_MASK 0xffff 133 134 #define STTS424E_DEVID 0x0000 135 #define STTS424E_DEVID_MASK 0xfffe 136 137 #define STTS2002_DEVID 0x0300 138 #define STTS2002_DEVID_MASK 0xffff 139 140 #define STTS2004_DEVID 0x2201 141 #define STTS2004_DEVID_MASK 0xffff 142 143 #define STTS3000_DEVID 0x0200 144 #define STTS3000_DEVID_MASK 0xffff 145 146 static u16 jc42_hysteresis[] = { 0, 1500, 3000, 6000 }; 147 148 struct jc42_chips { 149 u16 manid; 150 u16 devid; 151 u16 devid_mask; 152 }; 153 154 static struct jc42_chips jc42_chips[] = { 155 { ADT_MANID, ADT7408_DEVID, ADT7408_DEVID_MASK }, 156 { ATMEL_MANID, AT30TS00_DEVID, AT30TS00_DEVID_MASK }, 157 { ATMEL_MANID2, AT30TSE004_DEVID, AT30TSE004_DEVID_MASK }, 158 { IDT_MANID, TSE2004_DEVID, TSE2004_DEVID_MASK }, 159 { IDT_MANID, TS3000_DEVID, TS3000_DEVID_MASK }, 160 { IDT_MANID, TS3001_DEVID, TS3001_DEVID_MASK }, 161 { MAX_MANID, MAX6604_DEVID, MAX6604_DEVID_MASK }, 162 { MCP_MANID, MCP9804_DEVID, MCP9804_DEVID_MASK }, 163 { MCP_MANID, MCP98242_DEVID, MCP98242_DEVID_MASK }, 164 { MCP_MANID, MCP98243_DEVID, MCP98243_DEVID_MASK }, 165 { MCP_MANID, MCP98244_DEVID, MCP98244_DEVID_MASK }, 166 { MCP_MANID, MCP9843_DEVID, MCP9843_DEVID_MASK }, 167 { NXP_MANID, SE97_DEVID, SE97_DEVID_MASK }, 168 { ONS_MANID, CAT6095_DEVID, CAT6095_DEVID_MASK }, 169 { NXP_MANID, SE98_DEVID, SE98_DEVID_MASK }, 170 { STM_MANID, STTS424_DEVID, STTS424_DEVID_MASK }, 171 { STM_MANID, STTS424E_DEVID, STTS424E_DEVID_MASK }, 172 { STM_MANID, STTS2002_DEVID, STTS2002_DEVID_MASK }, 173 { STM_MANID, STTS2004_DEVID, STTS2004_DEVID_MASK }, 174 { STM_MANID, STTS3000_DEVID, STTS3000_DEVID_MASK }, 175 }; 176 177 enum temp_index { 178 t_input = 0, 179 t_crit, 180 t_min, 181 t_max, 182 t_num_temp 183 }; 184 185 static const u8 temp_regs[t_num_temp] = { 186 [t_input] = JC42_REG_TEMP, 187 [t_crit] = JC42_REG_TEMP_CRITICAL, 188 [t_min] = JC42_REG_TEMP_LOWER, 189 [t_max] = JC42_REG_TEMP_UPPER, 190 }; 191 192 /* Each client has this additional data */ 193 struct jc42_data { 194 struct i2c_client *client; 195 struct mutex update_lock; /* protect register access */ 196 bool extended; /* true if extended range supported */ 197 bool valid; 198 unsigned long last_updated; /* In jiffies */ 199 u16 orig_config; /* original configuration */ 200 u16 config; /* current configuration */ 201 u16 temp[t_num_temp];/* Temperatures */ 202 }; 203 204 #define JC42_TEMP_MIN_EXTENDED (-40000) 205 #define JC42_TEMP_MIN 0 206 #define JC42_TEMP_MAX 125000 207 208 static u16 jc42_temp_to_reg(long temp, bool extended) 209 { 210 int ntemp = clamp_val(temp, 211 extended ? JC42_TEMP_MIN_EXTENDED : 212 JC42_TEMP_MIN, JC42_TEMP_MAX); 213 214 /* convert from 0.001 to 0.0625 resolution */ 215 return (ntemp * 2 / 125) & 0x1fff; 216 } 217 218 static int jc42_temp_from_reg(s16 reg) 219 { 220 reg = sign_extend32(reg, 12); 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 long val; 312 int diff, hyst; 313 int err; 314 int ret = count; 315 316 if (kstrtol(buf, 10, &val) < 0) 317 return -EINVAL; 318 319 val = clamp_val(val, (data->extended ? JC42_TEMP_MIN_EXTENDED : 320 JC42_TEMP_MIN) - 6000, JC42_TEMP_MAX); 321 diff = jc42_temp_from_reg(data->temp[t_crit]) - val; 322 323 hyst = 0; 324 if (diff > 0) { 325 if (diff < 2250) 326 hyst = 1; /* 1.5 degrees C */ 327 else if (diff < 4500) 328 hyst = 2; /* 3.0 degrees C */ 329 else 330 hyst = 3; /* 6.0 degrees C */ 331 } 332 333 mutex_lock(&data->update_lock); 334 data->config = (data->config & ~JC42_CFG_HYST_MASK) 335 | (hyst << JC42_CFG_HYST_SHIFT); 336 err = i2c_smbus_write_word_swapped(data->client, JC42_REG_CONFIG, 337 data->config); 338 if (err < 0) 339 ret = err; 340 mutex_unlock(&data->update_lock); 341 return ret; 342 } 343 344 static ssize_t show_alarm(struct device *dev, 345 struct device_attribute *attr, char *buf) 346 { 347 u16 bit = to_sensor_dev_attr(attr)->index; 348 struct jc42_data *data = jc42_update_device(dev); 349 u16 val; 350 351 if (IS_ERR(data)) 352 return PTR_ERR(data); 353 354 val = data->temp[t_input]; 355 if (bit != JC42_ALARM_CRIT_BIT && (data->config & JC42_CFG_CRIT_ONLY)) 356 val = 0; 357 return sprintf(buf, "%u\n", (val >> bit) & 1); 358 } 359 360 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, t_input); 361 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, set_temp, t_crit); 362 static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO, show_temp, set_temp, t_min); 363 static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp, set_temp, t_max); 364 365 static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IRUGO, show_temp_hyst, 366 set_temp_crit_hyst, t_crit); 367 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IRUGO, show_temp_hyst, NULL, t_max); 368 369 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 370 JC42_ALARM_CRIT_BIT); 371 static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 372 JC42_ALARM_MIN_BIT); 373 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 374 JC42_ALARM_MAX_BIT); 375 376 static struct attribute *jc42_attributes[] = { 377 &sensor_dev_attr_temp1_input.dev_attr.attr, 378 &sensor_dev_attr_temp1_crit.dev_attr.attr, 379 &sensor_dev_attr_temp1_min.dev_attr.attr, 380 &sensor_dev_attr_temp1_max.dev_attr.attr, 381 &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr, 382 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 383 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, 384 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr, 385 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, 386 NULL 387 }; 388 389 static umode_t jc42_attribute_mode(struct kobject *kobj, 390 struct attribute *attr, int index) 391 { 392 struct device *dev = container_of(kobj, struct device, kobj); 393 struct jc42_data *data = dev_get_drvdata(dev); 394 unsigned int config = data->config; 395 bool readonly; 396 397 if (attr == &sensor_dev_attr_temp1_crit.dev_attr.attr) 398 readonly = config & JC42_CFG_TCRIT_LOCK; 399 else if (attr == &sensor_dev_attr_temp1_min.dev_attr.attr || 400 attr == &sensor_dev_attr_temp1_max.dev_attr.attr) 401 readonly = config & JC42_CFG_EVENT_LOCK; 402 else if (attr == &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr) 403 readonly = config & (JC42_CFG_EVENT_LOCK | JC42_CFG_TCRIT_LOCK); 404 else 405 readonly = true; 406 407 return S_IRUGO | (readonly ? 0 : S_IWUSR); 408 } 409 410 static const struct attribute_group jc42_group = { 411 .attrs = jc42_attributes, 412 .is_visible = jc42_attribute_mode, 413 }; 414 __ATTRIBUTE_GROUPS(jc42); 415 416 /* Return 0 if detection is successful, -ENODEV otherwise */ 417 static int jc42_detect(struct i2c_client *client, struct i2c_board_info *info) 418 { 419 struct i2c_adapter *adapter = client->adapter; 420 int i, config, cap, manid, devid; 421 422 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | 423 I2C_FUNC_SMBUS_WORD_DATA)) 424 return -ENODEV; 425 426 cap = i2c_smbus_read_word_swapped(client, JC42_REG_CAP); 427 config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG); 428 manid = i2c_smbus_read_word_swapped(client, JC42_REG_MANID); 429 devid = i2c_smbus_read_word_swapped(client, JC42_REG_DEVICEID); 430 431 if (cap < 0 || config < 0 || manid < 0 || devid < 0) 432 return -ENODEV; 433 434 if ((cap & 0xff00) || (config & 0xf800)) 435 return -ENODEV; 436 437 for (i = 0; i < ARRAY_SIZE(jc42_chips); i++) { 438 struct jc42_chips *chip = &jc42_chips[i]; 439 if (manid == chip->manid && 440 (devid & chip->devid_mask) == chip->devid) { 441 strlcpy(info->type, "jc42", I2C_NAME_SIZE); 442 return 0; 443 } 444 } 445 return -ENODEV; 446 } 447 448 static int jc42_probe(struct i2c_client *client, const struct i2c_device_id *id) 449 { 450 struct device *dev = &client->dev; 451 struct device *hwmon_dev; 452 struct jc42_data *data; 453 int config, cap; 454 455 data = devm_kzalloc(dev, sizeof(struct jc42_data), GFP_KERNEL); 456 if (!data) 457 return -ENOMEM; 458 459 data->client = client; 460 i2c_set_clientdata(client, data); 461 mutex_init(&data->update_lock); 462 463 cap = i2c_smbus_read_word_swapped(client, JC42_REG_CAP); 464 if (cap < 0) 465 return cap; 466 467 data->extended = !!(cap & JC42_CAP_RANGE); 468 469 config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG); 470 if (config < 0) 471 return config; 472 473 data->orig_config = config; 474 if (config & JC42_CFG_SHUTDOWN) { 475 config &= ~JC42_CFG_SHUTDOWN; 476 i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, config); 477 } 478 data->config = config; 479 480 hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, 481 data, 482 jc42_groups); 483 return PTR_ERR_OR_ZERO(hwmon_dev); 484 } 485 486 static int jc42_remove(struct i2c_client *client) 487 { 488 struct jc42_data *data = i2c_get_clientdata(client); 489 490 /* Restore original configuration except hysteresis */ 491 if ((data->config & ~JC42_CFG_HYST_MASK) != 492 (data->orig_config & ~JC42_CFG_HYST_MASK)) { 493 int config; 494 495 config = (data->orig_config & ~JC42_CFG_HYST_MASK) 496 | (data->config & JC42_CFG_HYST_MASK); 497 i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, config); 498 } 499 return 0; 500 } 501 502 #ifdef CONFIG_PM 503 504 static int jc42_suspend(struct device *dev) 505 { 506 struct jc42_data *data = dev_get_drvdata(dev); 507 508 data->config |= JC42_CFG_SHUTDOWN; 509 i2c_smbus_write_word_swapped(data->client, JC42_REG_CONFIG, 510 data->config); 511 return 0; 512 } 513 514 static int jc42_resume(struct device *dev) 515 { 516 struct jc42_data *data = dev_get_drvdata(dev); 517 518 data->config &= ~JC42_CFG_SHUTDOWN; 519 i2c_smbus_write_word_swapped(data->client, JC42_REG_CONFIG, 520 data->config); 521 return 0; 522 } 523 524 static const struct dev_pm_ops jc42_dev_pm_ops = { 525 .suspend = jc42_suspend, 526 .resume = jc42_resume, 527 }; 528 529 #define JC42_DEV_PM_OPS (&jc42_dev_pm_ops) 530 #else 531 #define JC42_DEV_PM_OPS NULL 532 #endif /* CONFIG_PM */ 533 534 static const struct i2c_device_id jc42_id[] = { 535 { "jc42", 0 }, 536 { } 537 }; 538 MODULE_DEVICE_TABLE(i2c, jc42_id); 539 540 static struct i2c_driver jc42_driver = { 541 .class = I2C_CLASS_SPD, 542 .driver = { 543 .name = "jc42", 544 .pm = JC42_DEV_PM_OPS, 545 }, 546 .probe = jc42_probe, 547 .remove = jc42_remove, 548 .id_table = jc42_id, 549 .detect = jc42_detect, 550 .address_list = normal_i2c, 551 }; 552 553 module_i2c_driver(jc42_driver); 554 555 MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>"); 556 MODULE_DESCRIPTION("JC42 driver"); 557 MODULE_LICENSE("GPL"); 558