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_temp_show(struct device *dev, 234 struct device_attribute *da, char *buf) 235 { 236 struct sensor_device_attribute *attr = to_sensor_dev_attr(da); 237 struct adt7x10_data *data = dev_get_drvdata(dev); 238 239 240 if (attr->index == 0) { 241 int ret; 242 243 ret = adt7x10_update_temp(dev); 244 if (ret) 245 return ret; 246 } 247 248 return sprintf(buf, "%d\n", ADT7X10_REG_TO_TEMP(data, 249 data->temp[attr->index])); 250 } 251 252 static ssize_t adt7x10_temp_store(struct device *dev, 253 struct device_attribute *da, 254 const char *buf, size_t count) 255 { 256 struct sensor_device_attribute *attr = to_sensor_dev_attr(da); 257 struct adt7x10_data *data = dev_get_drvdata(dev); 258 int nr = attr->index; 259 long temp; 260 int ret; 261 262 ret = kstrtol(buf, 10, &temp); 263 if (ret) 264 return ret; 265 266 mutex_lock(&data->update_lock); 267 data->temp[nr] = ADT7X10_TEMP_TO_REG(temp); 268 ret = adt7x10_write_word(dev, ADT7X10_REG_TEMP[nr], data->temp[nr]); 269 if (ret) 270 count = ret; 271 mutex_unlock(&data->update_lock); 272 return count; 273 } 274 275 static ssize_t adt7x10_t_hyst_show(struct device *dev, 276 struct device_attribute *da, char *buf) 277 { 278 struct sensor_device_attribute *attr = to_sensor_dev_attr(da); 279 struct adt7x10_data *data = dev_get_drvdata(dev); 280 int nr = attr->index; 281 int hyst; 282 283 hyst = (data->hyst & ADT7X10_T_HYST_MASK) * 1000; 284 285 /* 286 * hysteresis is stored as a 4 bit offset in the device, convert it 287 * to an absolute value 288 */ 289 if (nr == 2) /* min has positive offset, others have negative */ 290 hyst = -hyst; 291 return sprintf(buf, "%d\n", 292 ADT7X10_REG_TO_TEMP(data, data->temp[nr]) - hyst); 293 } 294 295 static ssize_t adt7x10_t_hyst_store(struct device *dev, 296 struct device_attribute *da, 297 const char *buf, size_t count) 298 { 299 struct adt7x10_data *data = dev_get_drvdata(dev); 300 int limit, ret; 301 long hyst; 302 303 ret = kstrtol(buf, 10, &hyst); 304 if (ret) 305 return ret; 306 /* convert absolute hysteresis value to a 4 bit delta value */ 307 limit = ADT7X10_REG_TO_TEMP(data, data->temp[1]); 308 hyst = clamp_val(hyst, ADT7X10_TEMP_MIN, ADT7X10_TEMP_MAX); 309 data->hyst = clamp_val(DIV_ROUND_CLOSEST(limit - hyst, 1000), 310 0, ADT7X10_T_HYST_MASK); 311 ret = adt7x10_write_byte(dev, ADT7X10_T_HYST, data->hyst); 312 if (ret) 313 return ret; 314 315 return count; 316 } 317 318 static ssize_t adt7x10_alarm_show(struct device *dev, 319 struct device_attribute *da, char *buf) 320 { 321 struct sensor_device_attribute *attr = to_sensor_dev_attr(da); 322 int ret; 323 324 ret = adt7x10_read_byte(dev, ADT7X10_STATUS); 325 if (ret < 0) 326 return ret; 327 328 return sprintf(buf, "%d\n", !!(ret & attr->index)); 329 } 330 331 static ssize_t name_show(struct device *dev, struct device_attribute *da, 332 char *buf) 333 { 334 struct adt7x10_data *data = dev_get_drvdata(dev); 335 336 return sprintf(buf, "%s\n", data->name); 337 } 338 339 static SENSOR_DEVICE_ATTR_RO(temp1_input, adt7x10_temp, 0); 340 static SENSOR_DEVICE_ATTR_RW(temp1_max, adt7x10_temp, 1); 341 static SENSOR_DEVICE_ATTR_RW(temp1_min, adt7x10_temp, 2); 342 static SENSOR_DEVICE_ATTR_RW(temp1_crit, adt7x10_temp, 3); 343 static SENSOR_DEVICE_ATTR_RW(temp1_max_hyst, adt7x10_t_hyst, 1); 344 static SENSOR_DEVICE_ATTR_RO(temp1_min_hyst, adt7x10_t_hyst, 2); 345 static SENSOR_DEVICE_ATTR_RO(temp1_crit_hyst, adt7x10_t_hyst, 3); 346 static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, adt7x10_alarm, 347 ADT7X10_STAT_T_LOW); 348 static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, adt7x10_alarm, 349 ADT7X10_STAT_T_HIGH); 350 static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, adt7x10_alarm, 351 ADT7X10_STAT_T_CRIT); 352 static DEVICE_ATTR_RO(name); 353 354 static struct attribute *adt7x10_attributes[] = { 355 &sensor_dev_attr_temp1_input.dev_attr.attr, 356 &sensor_dev_attr_temp1_max.dev_attr.attr, 357 &sensor_dev_attr_temp1_min.dev_attr.attr, 358 &sensor_dev_attr_temp1_crit.dev_attr.attr, 359 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 360 &sensor_dev_attr_temp1_min_hyst.dev_attr.attr, 361 &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr, 362 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr, 363 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, 364 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, 365 NULL 366 }; 367 368 static const struct attribute_group adt7x10_group = { 369 .attrs = adt7x10_attributes, 370 }; 371 372 int adt7x10_probe(struct device *dev, const char *name, int irq, 373 const struct adt7x10_ops *ops) 374 { 375 struct adt7x10_data *data; 376 int ret; 377 378 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); 379 if (!data) 380 return -ENOMEM; 381 382 data->ops = ops; 383 data->name = name; 384 385 dev_set_drvdata(dev, data); 386 mutex_init(&data->update_lock); 387 388 /* configure as specified */ 389 ret = adt7x10_read_byte(dev, ADT7X10_CONFIG); 390 if (ret < 0) { 391 dev_dbg(dev, "Can't read config? %d\n", ret); 392 return ret; 393 } 394 data->oldconfig = ret; 395 396 /* 397 * Set to 16 bit resolution, continous conversion and comparator mode. 398 */ 399 data->config = data->oldconfig; 400 data->config &= ~(ADT7X10_MODE_MASK | ADT7X10_CT_POLARITY | 401 ADT7X10_INT_POLARITY); 402 data->config |= ADT7X10_FULL | ADT7X10_RESOLUTION | ADT7X10_EVENT_MODE; 403 404 if (data->config != data->oldconfig) { 405 ret = adt7x10_write_byte(dev, ADT7X10_CONFIG, data->config); 406 if (ret) 407 return ret; 408 } 409 dev_dbg(dev, "Config %02x\n", data->config); 410 411 ret = adt7x10_fill_cache(dev); 412 if (ret) 413 goto exit_restore; 414 415 /* Register sysfs hooks */ 416 ret = sysfs_create_group(&dev->kobj, &adt7x10_group); 417 if (ret) 418 goto exit_restore; 419 420 /* 421 * The I2C device will already have it's own 'name' attribute, but for 422 * the SPI device we need to register it. name will only be non NULL if 423 * the device doesn't register the 'name' attribute on its own. 424 */ 425 if (name) { 426 ret = device_create_file(dev, &dev_attr_name); 427 if (ret) 428 goto exit_remove; 429 } 430 431 data->hwmon_dev = hwmon_device_register(dev); 432 if (IS_ERR(data->hwmon_dev)) { 433 ret = PTR_ERR(data->hwmon_dev); 434 goto exit_remove_name; 435 } 436 437 if (irq > 0) { 438 ret = request_threaded_irq(irq, NULL, adt7x10_irq_handler, 439 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 440 dev_name(dev), dev); 441 if (ret) 442 goto exit_hwmon_device_unregister; 443 } 444 445 return 0; 446 447 exit_hwmon_device_unregister: 448 hwmon_device_unregister(data->hwmon_dev); 449 exit_remove_name: 450 if (name) 451 device_remove_file(dev, &dev_attr_name); 452 exit_remove: 453 sysfs_remove_group(&dev->kobj, &adt7x10_group); 454 exit_restore: 455 adt7x10_write_byte(dev, ADT7X10_CONFIG, data->oldconfig); 456 return ret; 457 } 458 EXPORT_SYMBOL_GPL(adt7x10_probe); 459 460 int adt7x10_remove(struct device *dev, int irq) 461 { 462 struct adt7x10_data *data = dev_get_drvdata(dev); 463 464 if (irq > 0) 465 free_irq(irq, dev); 466 467 hwmon_device_unregister(data->hwmon_dev); 468 if (data->name) 469 device_remove_file(dev, &dev_attr_name); 470 sysfs_remove_group(&dev->kobj, &adt7x10_group); 471 if (data->oldconfig != data->config) 472 adt7x10_write_byte(dev, ADT7X10_CONFIG, data->oldconfig); 473 return 0; 474 } 475 EXPORT_SYMBOL_GPL(adt7x10_remove); 476 477 #ifdef CONFIG_PM_SLEEP 478 479 static int adt7x10_suspend(struct device *dev) 480 { 481 struct adt7x10_data *data = dev_get_drvdata(dev); 482 483 return adt7x10_write_byte(dev, ADT7X10_CONFIG, 484 data->config | ADT7X10_PD); 485 } 486 487 static int adt7x10_resume(struct device *dev) 488 { 489 struct adt7x10_data *data = dev_get_drvdata(dev); 490 491 return adt7x10_write_byte(dev, ADT7X10_CONFIG, data->config); 492 } 493 494 SIMPLE_DEV_PM_OPS(adt7x10_dev_pm_ops, adt7x10_suspend, adt7x10_resume); 495 EXPORT_SYMBOL_GPL(adt7x10_dev_pm_ops); 496 497 #endif /* CONFIG_PM_SLEEP */ 498 499 MODULE_AUTHOR("Hartmut Knaack"); 500 MODULE_DESCRIPTION("ADT7410/ADT7420, ADT7310/ADT7320 common code"); 501 MODULE_LICENSE("GPL"); 502