1 /* 2 * adt7x10.c - Part of lm_sensors, Linux kernel modules for hardware 3 * monitoring 4 * This driver handles the ADT7410 and compatible digital temperature sensors. 5 * Hartmut Knaack <knaack.h@gmx.de> 2012-07-22 6 * based on lm75.c by Frodo Looijaard <frodol@dds.nl> 7 * and adt7410.c from iio-staging by Sonic Zhang <sonic.zhang@analog.com> 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; either version 2 of the License, or 12 * (at your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 * GNU General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, write to the Free Software 21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 22 */ 23 24 #include <linux/module.h> 25 #include <linux/init.h> 26 #include <linux/slab.h> 27 #include <linux/jiffies.h> 28 #include <linux/hwmon.h> 29 #include <linux/hwmon-sysfs.h> 30 #include <linux/err.h> 31 #include <linux/mutex.h> 32 #include <linux/delay.h> 33 #include <linux/interrupt.h> 34 35 #include "adt7x10.h" 36 37 /* 38 * ADT7X10 status 39 */ 40 #define ADT7X10_STAT_T_LOW (1 << 4) 41 #define ADT7X10_STAT_T_HIGH (1 << 5) 42 #define ADT7X10_STAT_T_CRIT (1 << 6) 43 #define ADT7X10_STAT_NOT_RDY (1 << 7) 44 45 /* 46 * ADT7X10 config 47 */ 48 #define ADT7X10_FAULT_QUEUE_MASK (1 << 0 | 1 << 1) 49 #define ADT7X10_CT_POLARITY (1 << 2) 50 #define ADT7X10_INT_POLARITY (1 << 3) 51 #define ADT7X10_EVENT_MODE (1 << 4) 52 #define ADT7X10_MODE_MASK (1 << 5 | 1 << 6) 53 #define ADT7X10_FULL (0 << 5 | 0 << 6) 54 #define ADT7X10_PD (1 << 5 | 1 << 6) 55 #define ADT7X10_RESOLUTION (1 << 7) 56 57 /* 58 * ADT7X10 masks 59 */ 60 #define ADT7X10_T13_VALUE_MASK 0xFFF8 61 #define ADT7X10_T_HYST_MASK 0xF 62 63 /* straight from the datasheet */ 64 #define ADT7X10_TEMP_MIN (-55000) 65 #define ADT7X10_TEMP_MAX 150000 66 67 /* Each client has this additional data */ 68 struct adt7x10_data { 69 const struct adt7x10_ops *ops; 70 const char *name; 71 struct device *hwmon_dev; 72 struct mutex update_lock; 73 u8 config; 74 u8 oldconfig; 75 bool valid; /* true if registers valid */ 76 unsigned long last_updated; /* In jiffies */ 77 s16 temp[4]; /* Register values, 78 0 = input 79 1 = high 80 2 = low 81 3 = critical */ 82 u8 hyst; /* hysteresis offset */ 83 }; 84 85 static int adt7x10_read_byte(struct device *dev, u8 reg) 86 { 87 struct adt7x10_data *d = dev_get_drvdata(dev); 88 return d->ops->read_byte(dev, reg); 89 } 90 91 static int adt7x10_write_byte(struct device *dev, u8 reg, u8 data) 92 { 93 struct adt7x10_data *d = dev_get_drvdata(dev); 94 return d->ops->write_byte(dev, reg, data); 95 } 96 97 static int adt7x10_read_word(struct device *dev, u8 reg) 98 { 99 struct adt7x10_data *d = dev_get_drvdata(dev); 100 return d->ops->read_word(dev, reg); 101 } 102 103 static int adt7x10_write_word(struct device *dev, u8 reg, u16 data) 104 { 105 struct adt7x10_data *d = dev_get_drvdata(dev); 106 return d->ops->write_word(dev, reg, data); 107 } 108 109 static const u8 ADT7X10_REG_TEMP[4] = { 110 ADT7X10_TEMPERATURE, /* input */ 111 ADT7X10_T_ALARM_HIGH, /* high */ 112 ADT7X10_T_ALARM_LOW, /* low */ 113 ADT7X10_T_CRIT, /* critical */ 114 }; 115 116 static irqreturn_t adt7x10_irq_handler(int irq, void *private) 117 { 118 struct device *dev = private; 119 int status; 120 121 status = adt7x10_read_byte(dev, ADT7X10_STATUS); 122 if (status < 0) 123 return IRQ_HANDLED; 124 125 if (status & ADT7X10_STAT_T_HIGH) 126 sysfs_notify(&dev->kobj, NULL, "temp1_max_alarm"); 127 if (status & ADT7X10_STAT_T_LOW) 128 sysfs_notify(&dev->kobj, NULL, "temp1_min_alarm"); 129 if (status & ADT7X10_STAT_T_CRIT) 130 sysfs_notify(&dev->kobj, NULL, "temp1_crit_alarm"); 131 132 return IRQ_HANDLED; 133 } 134 135 static int adt7x10_temp_ready(struct device *dev) 136 { 137 int i, status; 138 139 for (i = 0; i < 6; i++) { 140 status = adt7x10_read_byte(dev, ADT7X10_STATUS); 141 if (status < 0) 142 return status; 143 if (!(status & ADT7X10_STAT_NOT_RDY)) 144 return 0; 145 msleep(60); 146 } 147 return -ETIMEDOUT; 148 } 149 150 static int adt7x10_update_temp(struct device *dev) 151 { 152 struct adt7x10_data *data = dev_get_drvdata(dev); 153 int ret = 0; 154 155 mutex_lock(&data->update_lock); 156 157 if (time_after(jiffies, data->last_updated + HZ + HZ / 2) 158 || !data->valid) { 159 int temp; 160 161 dev_dbg(dev, "Starting update\n"); 162 163 ret = adt7x10_temp_ready(dev); /* check for new value */ 164 if (ret) 165 goto abort; 166 167 temp = adt7x10_read_word(dev, ADT7X10_REG_TEMP[0]); 168 if (temp < 0) { 169 ret = temp; 170 dev_dbg(dev, "Failed to read value: reg %d, error %d\n", 171 ADT7X10_REG_TEMP[0], ret); 172 goto abort; 173 } 174 data->temp[0] = temp; 175 data->last_updated = jiffies; 176 data->valid = true; 177 } 178 179 abort: 180 mutex_unlock(&data->update_lock); 181 return ret; 182 } 183 184 static int adt7x10_fill_cache(struct device *dev) 185 { 186 struct adt7x10_data *data = dev_get_drvdata(dev); 187 int ret; 188 int i; 189 190 for (i = 1; i < ARRAY_SIZE(data->temp); i++) { 191 ret = adt7x10_read_word(dev, ADT7X10_REG_TEMP[i]); 192 if (ret < 0) { 193 dev_dbg(dev, "Failed to read value: reg %d, error %d\n", 194 ADT7X10_REG_TEMP[i], ret); 195 return ret; 196 } 197 data->temp[i] = ret; 198 } 199 200 ret = adt7x10_read_byte(dev, ADT7X10_T_HYST); 201 if (ret < 0) { 202 dev_dbg(dev, "Failed to read value: reg %d, error %d\n", 203 ADT7X10_T_HYST, ret); 204 return ret; 205 } 206 data->hyst = ret; 207 208 return 0; 209 } 210 211 static s16 ADT7X10_TEMP_TO_REG(long temp) 212 { 213 return DIV_ROUND_CLOSEST(clamp_val(temp, ADT7X10_TEMP_MIN, 214 ADT7X10_TEMP_MAX) * 128, 1000); 215 } 216 217 static int ADT7X10_REG_TO_TEMP(struct adt7x10_data *data, s16 reg) 218 { 219 /* in 13 bit mode, bits 0-2 are status flags - mask them out */ 220 if (!(data->config & ADT7X10_RESOLUTION)) 221 reg &= ADT7X10_T13_VALUE_MASK; 222 /* 223 * temperature is stored in twos complement format, in steps of 224 * 1/128°C 225 */ 226 return DIV_ROUND_CLOSEST(reg * 1000, 128); 227 } 228 229 /*-----------------------------------------------------------------------*/ 230 231 /* sysfs attributes for hwmon */ 232 233 static ssize_t adt7x10_show_temp(struct device *dev, 234 struct device_attribute *da, 235 char *buf) 236 { 237 struct sensor_device_attribute *attr = to_sensor_dev_attr(da); 238 struct adt7x10_data *data = dev_get_drvdata(dev); 239 240 241 if (attr->index == 0) { 242 int ret; 243 244 ret = adt7x10_update_temp(dev); 245 if (ret) 246 return ret; 247 } 248 249 return sprintf(buf, "%d\n", ADT7X10_REG_TO_TEMP(data, 250 data->temp[attr->index])); 251 } 252 253 static ssize_t adt7x10_set_temp(struct device *dev, 254 struct device_attribute *da, 255 const char *buf, size_t count) 256 { 257 struct sensor_device_attribute *attr = to_sensor_dev_attr(da); 258 struct adt7x10_data *data = dev_get_drvdata(dev); 259 int nr = attr->index; 260 long temp; 261 int ret; 262 263 ret = kstrtol(buf, 10, &temp); 264 if (ret) 265 return ret; 266 267 mutex_lock(&data->update_lock); 268 data->temp[nr] = ADT7X10_TEMP_TO_REG(temp); 269 ret = adt7x10_write_word(dev, ADT7X10_REG_TEMP[nr], data->temp[nr]); 270 if (ret) 271 count = ret; 272 mutex_unlock(&data->update_lock); 273 return count; 274 } 275 276 static ssize_t adt7x10_show_t_hyst(struct device *dev, 277 struct device_attribute *da, 278 char *buf) 279 { 280 struct sensor_device_attribute *attr = to_sensor_dev_attr(da); 281 struct adt7x10_data *data = dev_get_drvdata(dev); 282 int nr = attr->index; 283 int hyst; 284 285 hyst = (data->hyst & ADT7X10_T_HYST_MASK) * 1000; 286 287 /* 288 * hysteresis is stored as a 4 bit offset in the device, convert it 289 * to an absolute value 290 */ 291 if (nr == 2) /* min has positive offset, others have negative */ 292 hyst = -hyst; 293 return sprintf(buf, "%d\n", 294 ADT7X10_REG_TO_TEMP(data, data->temp[nr]) - hyst); 295 } 296 297 static ssize_t adt7x10_set_t_hyst(struct device *dev, 298 struct device_attribute *da, 299 const char *buf, size_t count) 300 { 301 struct adt7x10_data *data = dev_get_drvdata(dev); 302 int limit, ret; 303 long hyst; 304 305 ret = kstrtol(buf, 10, &hyst); 306 if (ret) 307 return ret; 308 /* convert absolute hysteresis value to a 4 bit delta value */ 309 limit = ADT7X10_REG_TO_TEMP(data, data->temp[1]); 310 hyst = clamp_val(hyst, ADT7X10_TEMP_MIN, ADT7X10_TEMP_MAX); 311 data->hyst = clamp_val(DIV_ROUND_CLOSEST(limit - hyst, 1000), 312 0, ADT7X10_T_HYST_MASK); 313 ret = adt7x10_write_byte(dev, ADT7X10_T_HYST, data->hyst); 314 if (ret) 315 return ret; 316 317 return count; 318 } 319 320 static ssize_t adt7x10_show_alarm(struct device *dev, 321 struct device_attribute *da, 322 char *buf) 323 { 324 struct sensor_device_attribute *attr = to_sensor_dev_attr(da); 325 int ret; 326 327 ret = adt7x10_read_byte(dev, ADT7X10_STATUS); 328 if (ret < 0) 329 return ret; 330 331 return sprintf(buf, "%d\n", !!(ret & attr->index)); 332 } 333 334 static ssize_t name_show(struct device *dev, struct device_attribute *da, 335 char *buf) 336 { 337 struct adt7x10_data *data = dev_get_drvdata(dev); 338 339 return sprintf(buf, "%s\n", data->name); 340 } 341 342 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, adt7x10_show_temp, NULL, 0); 343 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, 344 adt7x10_show_temp, adt7x10_set_temp, 1); 345 static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, 346 adt7x10_show_temp, adt7x10_set_temp, 2); 347 static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, 348 adt7x10_show_temp, adt7x10_set_temp, 3); 349 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, 350 adt7x10_show_t_hyst, adt7x10_set_t_hyst, 1); 351 static SENSOR_DEVICE_ATTR(temp1_min_hyst, S_IRUGO, 352 adt7x10_show_t_hyst, NULL, 2); 353 static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IRUGO, 354 adt7x10_show_t_hyst, NULL, 3); 355 static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, adt7x10_show_alarm, 356 NULL, ADT7X10_STAT_T_LOW); 357 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, adt7x10_show_alarm, 358 NULL, ADT7X10_STAT_T_HIGH); 359 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, adt7x10_show_alarm, 360 NULL, ADT7X10_STAT_T_CRIT); 361 static DEVICE_ATTR_RO(name); 362 363 static struct attribute *adt7x10_attributes[] = { 364 &sensor_dev_attr_temp1_input.dev_attr.attr, 365 &sensor_dev_attr_temp1_max.dev_attr.attr, 366 &sensor_dev_attr_temp1_min.dev_attr.attr, 367 &sensor_dev_attr_temp1_crit.dev_attr.attr, 368 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 369 &sensor_dev_attr_temp1_min_hyst.dev_attr.attr, 370 &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr, 371 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr, 372 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, 373 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, 374 NULL 375 }; 376 377 static const struct attribute_group adt7x10_group = { 378 .attrs = adt7x10_attributes, 379 }; 380 381 int adt7x10_probe(struct device *dev, const char *name, int irq, 382 const struct adt7x10_ops *ops) 383 { 384 struct adt7x10_data *data; 385 int ret; 386 387 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); 388 if (!data) 389 return -ENOMEM; 390 391 data->ops = ops; 392 data->name = name; 393 394 dev_set_drvdata(dev, data); 395 mutex_init(&data->update_lock); 396 397 /* configure as specified */ 398 ret = adt7x10_read_byte(dev, ADT7X10_CONFIG); 399 if (ret < 0) { 400 dev_dbg(dev, "Can't read config? %d\n", ret); 401 return ret; 402 } 403 data->oldconfig = ret; 404 405 /* 406 * Set to 16 bit resolution, continous conversion and comparator mode. 407 */ 408 data->config = data->oldconfig; 409 data->config &= ~(ADT7X10_MODE_MASK | ADT7X10_CT_POLARITY | 410 ADT7X10_INT_POLARITY); 411 data->config |= ADT7X10_FULL | ADT7X10_RESOLUTION | ADT7X10_EVENT_MODE; 412 413 if (data->config != data->oldconfig) { 414 ret = adt7x10_write_byte(dev, ADT7X10_CONFIG, data->config); 415 if (ret) 416 return ret; 417 } 418 dev_dbg(dev, "Config %02x\n", data->config); 419 420 ret = adt7x10_fill_cache(dev); 421 if (ret) 422 goto exit_restore; 423 424 /* Register sysfs hooks */ 425 ret = sysfs_create_group(&dev->kobj, &adt7x10_group); 426 if (ret) 427 goto exit_restore; 428 429 /* 430 * The I2C device will already have it's own 'name' attribute, but for 431 * the SPI device we need to register it. name will only be non NULL if 432 * the device doesn't register the 'name' attribute on its own. 433 */ 434 if (name) { 435 ret = device_create_file(dev, &dev_attr_name); 436 if (ret) 437 goto exit_remove; 438 } 439 440 data->hwmon_dev = hwmon_device_register(dev); 441 if (IS_ERR(data->hwmon_dev)) { 442 ret = PTR_ERR(data->hwmon_dev); 443 goto exit_remove_name; 444 } 445 446 if (irq > 0) { 447 ret = request_threaded_irq(irq, NULL, adt7x10_irq_handler, 448 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 449 dev_name(dev), dev); 450 if (ret) 451 goto exit_hwmon_device_unregister; 452 } 453 454 return 0; 455 456 exit_hwmon_device_unregister: 457 hwmon_device_unregister(data->hwmon_dev); 458 exit_remove_name: 459 if (name) 460 device_remove_file(dev, &dev_attr_name); 461 exit_remove: 462 sysfs_remove_group(&dev->kobj, &adt7x10_group); 463 exit_restore: 464 adt7x10_write_byte(dev, ADT7X10_CONFIG, data->oldconfig); 465 return ret; 466 } 467 EXPORT_SYMBOL_GPL(adt7x10_probe); 468 469 int adt7x10_remove(struct device *dev, int irq) 470 { 471 struct adt7x10_data *data = dev_get_drvdata(dev); 472 473 if (irq > 0) 474 free_irq(irq, dev); 475 476 hwmon_device_unregister(data->hwmon_dev); 477 if (data->name) 478 device_remove_file(dev, &dev_attr_name); 479 sysfs_remove_group(&dev->kobj, &adt7x10_group); 480 if (data->oldconfig != data->config) 481 adt7x10_write_byte(dev, ADT7X10_CONFIG, data->oldconfig); 482 return 0; 483 } 484 EXPORT_SYMBOL_GPL(adt7x10_remove); 485 486 #ifdef CONFIG_PM_SLEEP 487 488 static int adt7x10_suspend(struct device *dev) 489 { 490 struct adt7x10_data *data = dev_get_drvdata(dev); 491 492 return adt7x10_write_byte(dev, ADT7X10_CONFIG, 493 data->config | ADT7X10_PD); 494 } 495 496 static int adt7x10_resume(struct device *dev) 497 { 498 struct adt7x10_data *data = dev_get_drvdata(dev); 499 500 return adt7x10_write_byte(dev, ADT7X10_CONFIG, data->config); 501 } 502 503 SIMPLE_DEV_PM_OPS(adt7x10_dev_pm_ops, adt7x10_suspend, adt7x10_resume); 504 EXPORT_SYMBOL_GPL(adt7x10_dev_pm_ops); 505 506 #endif /* CONFIG_PM_SLEEP */ 507 508 MODULE_AUTHOR("Hartmut Knaack"); 509 MODULE_DESCRIPTION("ADT7410/ADT7420, ADT7310/ADT7320 common code"); 510 MODULE_LICENSE("GPL"); 511