Lars-Peter Clausen | 51c2a48 | 2013-03-12 11:38:46 +0100 | [diff] [blame^] | 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 | |
| 34 | #include "adt7x10.h" |
| 35 | |
| 36 | /* |
| 37 | * ADT7X10 status |
| 38 | */ |
| 39 | #define ADT7X10_STAT_T_LOW (1 << 4) |
| 40 | #define ADT7X10_STAT_T_HIGH (1 << 5) |
| 41 | #define ADT7X10_STAT_T_CRIT (1 << 6) |
| 42 | #define ADT7X10_STAT_NOT_RDY (1 << 7) |
| 43 | |
| 44 | /* |
| 45 | * ADT7X10 config |
| 46 | */ |
| 47 | #define ADT7X10_FAULT_QUEUE_MASK (1 << 0 | 1 << 1) |
| 48 | #define ADT7X10_CT_POLARITY (1 << 2) |
| 49 | #define ADT7X10_INT_POLARITY (1 << 3) |
| 50 | #define ADT7X10_EVENT_MODE (1 << 4) |
| 51 | #define ADT7X10_MODE_MASK (1 << 5 | 1 << 6) |
| 52 | #define ADT7X10_FULL (0 << 5 | 0 << 6) |
| 53 | #define ADT7X10_PD (1 << 5 | 1 << 6) |
| 54 | #define ADT7X10_RESOLUTION (1 << 7) |
| 55 | |
| 56 | /* |
| 57 | * ADT7X10 masks |
| 58 | */ |
| 59 | #define ADT7X10_T13_VALUE_MASK 0xFFF8 |
| 60 | #define ADT7X10_T_HYST_MASK 0xF |
| 61 | |
| 62 | /* straight from the datasheet */ |
| 63 | #define ADT7X10_TEMP_MIN (-55000) |
| 64 | #define ADT7X10_TEMP_MAX 150000 |
| 65 | |
| 66 | /* Each client has this additional data */ |
| 67 | struct adt7x10_data { |
| 68 | const struct adt7x10_ops *ops; |
| 69 | const char *name; |
| 70 | struct device *hwmon_dev; |
| 71 | struct mutex update_lock; |
| 72 | u8 config; |
| 73 | u8 oldconfig; |
| 74 | bool valid; /* true if registers valid */ |
| 75 | unsigned long last_updated; /* In jiffies */ |
| 76 | s16 temp[4]; /* Register values, |
| 77 | 0 = input |
| 78 | 1 = high |
| 79 | 2 = low |
| 80 | 3 = critical */ |
| 81 | u8 hyst; /* hysteresis offset */ |
| 82 | }; |
| 83 | |
| 84 | static int adt7x10_read_byte(struct device *dev, u8 reg) |
| 85 | { |
| 86 | struct adt7x10_data *d = dev_get_drvdata(dev); |
| 87 | return d->ops->read_byte(dev, reg); |
| 88 | } |
| 89 | |
| 90 | static int adt7x10_write_byte(struct device *dev, u8 reg, u8 data) |
| 91 | { |
| 92 | struct adt7x10_data *d = dev_get_drvdata(dev); |
| 93 | return d->ops->write_byte(dev, reg, data); |
| 94 | } |
| 95 | |
| 96 | static int adt7x10_read_word(struct device *dev, u8 reg) |
| 97 | { |
| 98 | struct adt7x10_data *d = dev_get_drvdata(dev); |
| 99 | return d->ops->read_word(dev, reg); |
| 100 | } |
| 101 | |
| 102 | static int adt7x10_write_word(struct device *dev, u8 reg, u16 data) |
| 103 | { |
| 104 | struct adt7x10_data *d = dev_get_drvdata(dev); |
| 105 | return d->ops->write_word(dev, reg, data); |
| 106 | } |
| 107 | |
| 108 | static const u8 ADT7X10_REG_TEMP[4] = { |
| 109 | ADT7X10_TEMPERATURE, /* input */ |
| 110 | ADT7X10_T_ALARM_HIGH, /* high */ |
| 111 | ADT7X10_T_ALARM_LOW, /* low */ |
| 112 | ADT7X10_T_CRIT, /* critical */ |
| 113 | }; |
| 114 | |
| 115 | static int adt7x10_temp_ready(struct device *dev) |
| 116 | { |
| 117 | int i, status; |
| 118 | |
| 119 | for (i = 0; i < 6; i++) { |
| 120 | status = adt7x10_read_byte(dev, ADT7X10_STATUS); |
| 121 | if (status < 0) |
| 122 | return status; |
| 123 | if (!(status & ADT7X10_STAT_NOT_RDY)) |
| 124 | return 0; |
| 125 | msleep(60); |
| 126 | } |
| 127 | return -ETIMEDOUT; |
| 128 | } |
| 129 | |
| 130 | static int adt7x10_update_temp(struct device *dev) |
| 131 | { |
| 132 | struct adt7x10_data *data = dev_get_drvdata(dev); |
| 133 | int ret = 0; |
| 134 | |
| 135 | mutex_lock(&data->update_lock); |
| 136 | |
| 137 | if (time_after(jiffies, data->last_updated + HZ + HZ / 2) |
| 138 | || !data->valid) { |
| 139 | int temp; |
| 140 | |
| 141 | dev_dbg(dev, "Starting update\n"); |
| 142 | |
| 143 | ret = adt7x10_temp_ready(dev); /* check for new value */ |
| 144 | if (ret) |
| 145 | goto abort; |
| 146 | |
| 147 | temp = adt7x10_read_word(dev, ADT7X10_REG_TEMP[0]); |
| 148 | if (temp < 0) { |
| 149 | ret = temp; |
| 150 | dev_dbg(dev, "Failed to read value: reg %d, error %d\n", |
| 151 | ADT7X10_REG_TEMP[0], ret); |
| 152 | goto abort; |
| 153 | } |
| 154 | data->temp[0] = temp; |
| 155 | data->last_updated = jiffies; |
| 156 | data->valid = true; |
| 157 | } |
| 158 | |
| 159 | abort: |
| 160 | mutex_unlock(&data->update_lock); |
| 161 | return ret; |
| 162 | } |
| 163 | |
| 164 | static int adt7x10_fill_cache(struct device *dev) |
| 165 | { |
| 166 | struct adt7x10_data *data = dev_get_drvdata(dev); |
| 167 | int ret; |
| 168 | int i; |
| 169 | |
| 170 | for (i = 1; i < ARRAY_SIZE(data->temp); i++) { |
| 171 | ret = adt7x10_read_word(dev, ADT7X10_REG_TEMP[i]); |
| 172 | if (ret < 0) { |
| 173 | dev_dbg(dev, "Failed to read value: reg %d, error %d\n", |
| 174 | ADT7X10_REG_TEMP[i], ret); |
| 175 | return ret; |
| 176 | } |
| 177 | data->temp[i] = ret; |
| 178 | } |
| 179 | |
| 180 | ret = adt7x10_read_byte(dev, ADT7X10_T_HYST); |
| 181 | if (ret < 0) { |
| 182 | dev_dbg(dev, "Failed to read value: reg %d, error %d\n", |
| 183 | ADT7X10_T_HYST, ret); |
| 184 | return ret; |
| 185 | } |
| 186 | data->hyst = ret; |
| 187 | |
| 188 | return 0; |
| 189 | } |
| 190 | |
| 191 | static s16 ADT7X10_TEMP_TO_REG(long temp) |
| 192 | { |
| 193 | return DIV_ROUND_CLOSEST(clamp_val(temp, ADT7X10_TEMP_MIN, |
| 194 | ADT7X10_TEMP_MAX) * 128, 1000); |
| 195 | } |
| 196 | |
| 197 | static int ADT7X10_REG_TO_TEMP(struct adt7x10_data *data, s16 reg) |
| 198 | { |
| 199 | /* in 13 bit mode, bits 0-2 are status flags - mask them out */ |
| 200 | if (!(data->config & ADT7X10_RESOLUTION)) |
| 201 | reg &= ADT7X10_T13_VALUE_MASK; |
| 202 | /* |
| 203 | * temperature is stored in twos complement format, in steps of |
| 204 | * 1/128°C |
| 205 | */ |
| 206 | return DIV_ROUND_CLOSEST(reg * 1000, 128); |
| 207 | } |
| 208 | |
| 209 | /*-----------------------------------------------------------------------*/ |
| 210 | |
| 211 | /* sysfs attributes for hwmon */ |
| 212 | |
| 213 | static ssize_t adt7x10_show_temp(struct device *dev, |
| 214 | struct device_attribute *da, |
| 215 | char *buf) |
| 216 | { |
| 217 | struct sensor_device_attribute *attr = to_sensor_dev_attr(da); |
| 218 | struct adt7x10_data *data = dev_get_drvdata(dev); |
| 219 | |
| 220 | |
| 221 | if (attr->index == 0) { |
| 222 | int ret; |
| 223 | |
| 224 | ret = adt7x10_update_temp(dev); |
| 225 | if (ret) |
| 226 | return ret; |
| 227 | } |
| 228 | |
| 229 | return sprintf(buf, "%d\n", ADT7X10_REG_TO_TEMP(data, |
| 230 | data->temp[attr->index])); |
| 231 | } |
| 232 | |
| 233 | static ssize_t adt7x10_set_temp(struct device *dev, |
| 234 | struct device_attribute *da, |
| 235 | const char *buf, size_t count) |
| 236 | { |
| 237 | struct sensor_device_attribute *attr = to_sensor_dev_attr(da); |
| 238 | struct adt7x10_data *data = dev_get_drvdata(dev); |
| 239 | int nr = attr->index; |
| 240 | long temp; |
| 241 | int ret; |
| 242 | |
| 243 | ret = kstrtol(buf, 10, &temp); |
| 244 | if (ret) |
| 245 | return ret; |
| 246 | |
| 247 | mutex_lock(&data->update_lock); |
| 248 | data->temp[nr] = ADT7X10_TEMP_TO_REG(temp); |
| 249 | ret = adt7x10_write_word(dev, ADT7X10_REG_TEMP[nr], data->temp[nr]); |
| 250 | if (ret) |
| 251 | count = ret; |
| 252 | mutex_unlock(&data->update_lock); |
| 253 | return count; |
| 254 | } |
| 255 | |
| 256 | static ssize_t adt7x10_show_t_hyst(struct device *dev, |
| 257 | struct device_attribute *da, |
| 258 | char *buf) |
| 259 | { |
| 260 | struct sensor_device_attribute *attr = to_sensor_dev_attr(da); |
| 261 | struct adt7x10_data *data = dev_get_drvdata(dev); |
| 262 | int nr = attr->index; |
| 263 | int hyst; |
| 264 | |
| 265 | hyst = (data->hyst & ADT7X10_T_HYST_MASK) * 1000; |
| 266 | |
| 267 | /* |
| 268 | * hysteresis is stored as a 4 bit offset in the device, convert it |
| 269 | * to an absolute value |
| 270 | */ |
| 271 | if (nr == 2) /* min has positive offset, others have negative */ |
| 272 | hyst = -hyst; |
| 273 | return sprintf(buf, "%d\n", |
| 274 | ADT7X10_REG_TO_TEMP(data, data->temp[nr]) - hyst); |
| 275 | } |
| 276 | |
| 277 | static ssize_t adt7x10_set_t_hyst(struct device *dev, |
| 278 | struct device_attribute *da, |
| 279 | const char *buf, size_t count) |
| 280 | { |
| 281 | struct adt7x10_data *data = dev_get_drvdata(dev); |
| 282 | int limit, ret; |
| 283 | long hyst; |
| 284 | |
| 285 | ret = kstrtol(buf, 10, &hyst); |
| 286 | if (ret) |
| 287 | return ret; |
| 288 | /* convert absolute hysteresis value to a 4 bit delta value */ |
| 289 | limit = ADT7X10_REG_TO_TEMP(data, data->temp[1]); |
| 290 | hyst = clamp_val(hyst, ADT7X10_TEMP_MIN, ADT7X10_TEMP_MAX); |
| 291 | data->hyst = clamp_val(DIV_ROUND_CLOSEST(limit - hyst, 1000), |
| 292 | 0, ADT7X10_T_HYST_MASK); |
| 293 | ret = adt7x10_write_byte(dev, ADT7X10_T_HYST, data->hyst); |
| 294 | if (ret) |
| 295 | return ret; |
| 296 | |
| 297 | return count; |
| 298 | } |
| 299 | |
| 300 | static ssize_t adt7x10_show_alarm(struct device *dev, |
| 301 | struct device_attribute *da, |
| 302 | char *buf) |
| 303 | { |
| 304 | struct sensor_device_attribute *attr = to_sensor_dev_attr(da); |
| 305 | int ret; |
| 306 | |
| 307 | ret = adt7x10_read_byte(dev, ADT7X10_STATUS); |
| 308 | if (ret < 0) |
| 309 | return ret; |
| 310 | |
| 311 | return sprintf(buf, "%d\n", !!(ret & attr->index)); |
| 312 | } |
| 313 | |
| 314 | static ssize_t adt7x10_show_name(struct device *dev, |
| 315 | struct device_attribute *da, |
| 316 | char *buf) |
| 317 | { |
| 318 | struct adt7x10_data *data = dev_get_drvdata(dev); |
| 319 | |
| 320 | return sprintf(buf, "%s\n", data->name); |
| 321 | } |
| 322 | |
| 323 | static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, adt7x10_show_temp, NULL, 0); |
| 324 | static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, |
| 325 | adt7x10_show_temp, adt7x10_set_temp, 1); |
| 326 | static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, |
| 327 | adt7x10_show_temp, adt7x10_set_temp, 2); |
| 328 | static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, |
| 329 | adt7x10_show_temp, adt7x10_set_temp, 3); |
| 330 | static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, |
| 331 | adt7x10_show_t_hyst, adt7x10_set_t_hyst, 1); |
| 332 | static SENSOR_DEVICE_ATTR(temp1_min_hyst, S_IRUGO, |
| 333 | adt7x10_show_t_hyst, NULL, 2); |
| 334 | static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IRUGO, |
| 335 | adt7x10_show_t_hyst, NULL, 3); |
| 336 | static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, adt7x10_show_alarm, |
| 337 | NULL, ADT7X10_STAT_T_LOW); |
| 338 | static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, adt7x10_show_alarm, |
| 339 | NULL, ADT7X10_STAT_T_HIGH); |
| 340 | static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, adt7x10_show_alarm, |
| 341 | NULL, ADT7X10_STAT_T_CRIT); |
| 342 | static DEVICE_ATTR(name, S_IRUGO, adt7x10_show_name, NULL); |
| 343 | |
| 344 | static struct attribute *adt7x10_attributes[] = { |
| 345 | &sensor_dev_attr_temp1_input.dev_attr.attr, |
| 346 | &sensor_dev_attr_temp1_max.dev_attr.attr, |
| 347 | &sensor_dev_attr_temp1_min.dev_attr.attr, |
| 348 | &sensor_dev_attr_temp1_crit.dev_attr.attr, |
| 349 | &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, |
| 350 | &sensor_dev_attr_temp1_min_hyst.dev_attr.attr, |
| 351 | &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr, |
| 352 | &sensor_dev_attr_temp1_min_alarm.dev_attr.attr, |
| 353 | &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, |
| 354 | &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, |
| 355 | NULL |
| 356 | }; |
| 357 | |
| 358 | static const struct attribute_group adt7x10_group = { |
| 359 | .attrs = adt7x10_attributes, |
| 360 | }; |
| 361 | |
| 362 | int adt7x10_probe(struct device *dev, const char *name, |
| 363 | const struct adt7x10_ops *ops) |
| 364 | { |
| 365 | struct adt7x10_data *data; |
| 366 | int ret; |
| 367 | |
| 368 | data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); |
| 369 | if (!data) |
| 370 | return -ENOMEM; |
| 371 | |
| 372 | data->ops = ops; |
| 373 | data->name = name; |
| 374 | |
| 375 | dev_set_drvdata(dev, data); |
| 376 | mutex_init(&data->update_lock); |
| 377 | |
| 378 | /* configure as specified */ |
| 379 | ret = adt7x10_read_byte(dev, ADT7X10_CONFIG); |
| 380 | if (ret < 0) { |
| 381 | dev_dbg(dev, "Can't read config? %d\n", ret); |
| 382 | return ret; |
| 383 | } |
| 384 | data->oldconfig = ret; |
| 385 | |
| 386 | /* |
| 387 | * Set to 16 bit resolution, continous conversion and comparator mode. |
| 388 | */ |
| 389 | data->config = data->oldconfig; |
| 390 | data->config &= ~ADT7X10_MODE_MASK; |
| 391 | data->config |= ADT7X10_FULL | ADT7X10_RESOLUTION | ADT7X10_EVENT_MODE; |
| 392 | if (data->config != data->oldconfig) { |
| 393 | ret = adt7x10_write_byte(dev, ADT7X10_CONFIG, data->config); |
| 394 | if (ret) |
| 395 | return ret; |
| 396 | } |
| 397 | dev_dbg(dev, "Config %02x\n", data->config); |
| 398 | |
| 399 | ret = adt7x10_fill_cache(dev); |
| 400 | if (ret) |
| 401 | goto exit_restore; |
| 402 | |
| 403 | /* Register sysfs hooks */ |
| 404 | ret = sysfs_create_group(&dev->kobj, &adt7x10_group); |
| 405 | if (ret) |
| 406 | goto exit_restore; |
| 407 | |
| 408 | /* |
| 409 | * The I2C device will already have it's own 'name' attribute, but for |
| 410 | * the SPI device we need to register it. name will only be non NULL if |
| 411 | * the device doesn't register the 'name' attribute on its own. |
| 412 | */ |
| 413 | if (name) { |
| 414 | ret = device_create_file(dev, &dev_attr_name); |
| 415 | if (ret) |
| 416 | goto exit_remove; |
| 417 | } |
| 418 | |
| 419 | data->hwmon_dev = hwmon_device_register(dev); |
| 420 | if (IS_ERR(data->hwmon_dev)) { |
| 421 | ret = PTR_ERR(data->hwmon_dev); |
| 422 | goto exit_remove_name; |
| 423 | } |
| 424 | |
| 425 | return 0; |
| 426 | |
| 427 | exit_remove_name: |
| 428 | if (name) |
| 429 | device_remove_file(dev, &dev_attr_name); |
| 430 | exit_remove: |
| 431 | sysfs_remove_group(&dev->kobj, &adt7x10_group); |
| 432 | exit_restore: |
| 433 | adt7x10_write_byte(dev, ADT7X10_CONFIG, data->oldconfig); |
| 434 | return ret; |
| 435 | } |
| 436 | EXPORT_SYMBOL_GPL(adt7x10_probe); |
| 437 | |
| 438 | int adt7x10_remove(struct device *dev) |
| 439 | { |
| 440 | struct adt7x10_data *data = dev_get_drvdata(dev); |
| 441 | |
| 442 | hwmon_device_unregister(data->hwmon_dev); |
| 443 | if (data->name) |
| 444 | device_remove_file(dev, &dev_attr_name); |
| 445 | sysfs_remove_group(&dev->kobj, &adt7x10_group); |
| 446 | if (data->oldconfig != data->config) |
| 447 | adt7x10_write_byte(dev, ADT7X10_CONFIG, data->oldconfig); |
| 448 | return 0; |
| 449 | } |
| 450 | EXPORT_SYMBOL_GPL(adt7x10_remove); |
| 451 | |
| 452 | #ifdef CONFIG_PM_SLEEP |
| 453 | |
| 454 | static int adt7x10_suspend(struct device *dev) |
| 455 | { |
| 456 | struct adt7x10_data *data = dev_get_drvdata(dev); |
| 457 | |
| 458 | return adt7x10_write_byte(dev, ADT7X10_CONFIG, |
| 459 | data->config | ADT7X10_PD); |
| 460 | } |
| 461 | |
| 462 | static int adt7x10_resume(struct device *dev) |
| 463 | { |
| 464 | struct adt7x10_data *data = dev_get_drvdata(dev); |
| 465 | |
| 466 | return adt7x10_write_byte(dev, ADT7X10_CONFIG, data->config); |
| 467 | } |
| 468 | |
| 469 | SIMPLE_DEV_PM_OPS(adt7x10_dev_pm_ops, adt7x10_suspend, adt7x10_resume); |
| 470 | EXPORT_SYMBOL_GPL(adt7x10_dev_pm_ops); |
| 471 | |
| 472 | #endif /* CONFIG_PM_SLEEP */ |
| 473 | |
| 474 | MODULE_AUTHOR("Hartmut Knaack"); |
| 475 | MODULE_DESCRIPTION("ADT7410/ADT7420, ADT7310/ADT7320 common code"); |
| 476 | MODULE_LICENSE("GPL"); |