drivers/hwmon/adt7410.c

   1 /*
   2  * adt7410.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/i2c.h>
  29 #include <linux/hwmon.h>
  30 #include <linux/hwmon-sysfs.h>
  31 #include <linux/err.h>
  32 #include <linux/mutex.h>
  33 #include <linux/delay.h>
  34
  35 /*
  36  * ADT7410 registers definition
  37  */
  38
  39 #define ADT7410_TEMPERATURE             0
  40 #define ADT7410_STATUS                  2
  41 #define ADT7410_CONFIG                  3
  42 #define ADT7410_T_ALARM_HIGH            4
  43 #define ADT7410_T_ALARM_LOW             6
  44 #define ADT7410_T_CRIT                  8
  45 #define ADT7410_T_HYST                  0xA
  46
  47 /*
  48  * ADT7410 status
  49  */
  50 #define ADT7410_STAT_T_LOW              (1 << 4)
  51 #define ADT7410_STAT_T_HIGH             (1 << 5)
  52 #define ADT7410_STAT_T_CRIT             (1 << 6)
  53 #define ADT7410_STAT_NOT_RDY            (1 << 7)
  54
  55 /*
  56  * ADT7410 config
  57  */
  58 #define ADT7410_FAULT_QUEUE_MASK        (1 << 0 | 1 << 1)
  59 #define ADT7410_CT_POLARITY             (1 << 2)
  60 #define ADT7410_INT_POLARITY            (1 << 3)
  61 #define ADT7410_EVENT_MODE              (1 << 4)
  62 #define ADT7410_MODE_MASK               (1 << 5 | 1 << 6)
  63 #define ADT7410_FULL                    (0 << 5 | 0 << 6)
  64 #define ADT7410_PD                      (1 << 5 | 1 << 6)
  65 #define ADT7410_RESOLUTION              (1 << 7)
  66
  67 /*
  68  * ADT7410 masks
  69  */
  70 #define ADT7410_T13_VALUE_MASK                  0xFFF8
  71 #define ADT7410_T_HYST_MASK                     0xF
  72
  73 /* straight from the datasheet */
  74 #define ADT7410_TEMP_MIN (-55000)
  75 #define ADT7410_TEMP_MAX 150000
  76
  77 enum adt7410_type {             /* keep sorted in alphabetical order */
  78         adt7410,
  79 };
  80
  81 static const u8 ADT7410_REG_TEMP[4] = {
  82         ADT7410_TEMPERATURE,            /* input */
  83         ADT7410_T_ALARM_HIGH,           /* high */
  84         ADT7410_T_ALARM_LOW,            /* low */
  85         ADT7410_T_CRIT,                 /* critical */
  86 };
  87
  88 /* Each client has this additional data */
  89 struct adt7410_data {
  90         struct device           *hwmon_dev;
  91         struct mutex            update_lock;
  92         u8                      config;
  93         u8                      oldconfig;
  94         bool                    valid;          /* true if registers valid */
  95         unsigned long           last_updated;   /* In jiffies */
  96         s16                     temp[4];        /* Register values,
  97                                                    0 = input
  98                                                    1 = high
  99                                                    2 = low
 100                                                    3 = critical */
 101         u8                      hyst;           /* hysteresis offset */
 102 };
 103
 104 /*
 105  * adt7410 register access by I2C
 106  */
 107 static int adt7410_temp_ready(struct i2c_client *client)
 108 {
 109         int i, status;
 110
 111         for (i = 0; i < 6; i++) {
 112                 status = i2c_smbus_read_byte_data(client, ADT7410_STATUS);
 113                 if (status < 0)
 114                         return status;
 115                 if (!(status & ADT7410_STAT_NOT_RDY))
 116                         return 0;
 117                 msleep(60);
 118         }
 119         return -ETIMEDOUT;
 120 }
 121
 122 static struct adt7410_data *adt7410_update_device(struct device *dev)
 123 {
 124         struct i2c_client *client = to_i2c_client(dev);
 125         struct adt7410_data *data = i2c_get_clientdata(client);
 126         struct adt7410_data *ret = data;
 127         mutex_lock(&data->update_lock);
 128
 129         if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
 130             || !data->valid) {
 131                 int i, status;
 132
 133                 dev_dbg(&client->dev, "Starting update\n");
 134
 135                 status = adt7410_temp_ready(client); /* check for new value */
 136                 if (unlikely(status)) {
 137                         ret = ERR_PTR(status);
 138                         goto abort;
 139                 }
 140                 for (i = 0; i < ARRAY_SIZE(data->temp); i++) {
 141                         status = i2c_smbus_read_word_swapped(client,
 142                                                         ADT7410_REG_TEMP[i]);
 143                         if (unlikely(status < 0)) {
 144                                 dev_dbg(dev,
 145                                         "Failed to read value: reg %d, error %d\n",
 146                                         ADT7410_REG_TEMP[i], status);
 147                                 ret = ERR_PTR(status);
 148                                 goto abort;
 149                         }
 150                         data->temp[i] = status;
 151                 }
 152                 status = i2c_smbus_read_byte_data(client, ADT7410_T_HYST);
 153                 if (unlikely(status < 0)) {
 154                         dev_dbg(dev,
 155                                 "Failed to read value: reg %d, error %d\n",
 156                                 ADT7410_T_HYST, status);
 157                         ret = ERR_PTR(status);
 158                         goto abort;
 159                 }
 160                 data->hyst = status;
 161                 data->last_updated = jiffies;
 162                 data->valid = true;
 163         }
 164
 165 abort:
 166         mutex_unlock(&data->update_lock);
 167         return ret;
 168 }
 169
 170 static s16 ADT7410_TEMP_TO_REG(long temp)
 171 {
 172         return DIV_ROUND_CLOSEST(clamp_val(temp, ADT7410_TEMP_MIN,
 173                                            ADT7410_TEMP_MAX) * 128, 1000);
 174 }
 175
 176 static int ADT7410_REG_TO_TEMP(struct adt7410_data *data, s16 reg)
 177 {
 178         /* in 13 bit mode, bits 0-2 are status flags - mask them out */
 179         if (!(data->config & ADT7410_RESOLUTION))
 180                 reg &= ADT7410_T13_VALUE_MASK;
 181         /*
 182          * temperature is stored in twos complement format, in steps of
 183          * 1/128°C
 184          */
 185         return DIV_ROUND_CLOSEST(reg * 1000, 128);
 186 }
 187
 188 /*-----------------------------------------------------------------------*/
 189
 190 /* sysfs attributes for hwmon */
 191
 192 static ssize_t adt7410_show_temp(struct device *dev,
 193                                  struct device_attribute *da, char *buf)
 194 {
 195         struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
 196         struct adt7410_data *data = adt7410_update_device(dev);
 197
 198         if (IS_ERR(data))
 199                 return PTR_ERR(data);
 200
 201         return sprintf(buf, "%d\n", ADT7410_REG_TO_TEMP(data,
 202                        data->temp[attr->index]));
 203 }
 204
 205 static ssize_t adt7410_set_temp(struct device *dev,
 206                                 struct device_attribute *da,
 207                                 const char *buf, size_t count)
 208 {
 209         struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
 210         struct i2c_client *client = to_i2c_client(dev);
 211         struct adt7410_data *data = i2c_get_clientdata(client);
 212         int nr = attr->index;
 213         long temp;
 214         int ret;
 215
 216         ret = kstrtol(buf, 10, &temp);
 217         if (ret)
 218                 return ret;
 219
 220         mutex_lock(&data->update_lock);
 221         data->temp[nr] = ADT7410_TEMP_TO_REG(temp);
 222         ret = i2c_smbus_write_word_swapped(client, ADT7410_REG_TEMP[nr],
 223                                            data->temp[nr]);
 224         if (ret)
 225                 count = ret;
 226         mutex_unlock(&data->update_lock);
 227         return count;
 228 }
 229
 230 static ssize_t adt7410_show_t_hyst(struct device *dev,
 231                                    struct device_attribute *da,
 232                                    char *buf)
 233 {
 234         struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
 235         struct adt7410_data *data;
 236         int nr = attr->index;
 237         int hyst;
 238
 239         data = adt7410_update_device(dev);
 240         if (IS_ERR(data))
 241                 return PTR_ERR(data);
 242         hyst = (data->hyst & ADT7410_T_HYST_MASK) * 1000;
 243
 244         /*
 245          * hysteresis is stored as a 4 bit offset in the device, convert it
 246          * to an absolute value
 247          */
 248         if (nr == 2)    /* min has positive offset, others have negative */
 249                 hyst = -hyst;
 250         return sprintf(buf, "%d\n",
 251                        ADT7410_REG_TO_TEMP(data, data->temp[nr]) - hyst);
 252 }
 253
 254 static ssize_t adt7410_set_t_hyst(struct device *dev,
 255                                   struct device_attribute *da,
 256                                   const char *buf, size_t count)
 257 {
 258         struct i2c_client *client = to_i2c_client(dev);
 259         struct adt7410_data *data = i2c_get_clientdata(client);
 260         int limit, ret;
 261         long hyst;
 262
 263         ret = kstrtol(buf, 10, &hyst);
 264         if (ret)
 265                 return ret;
 266         /* convert absolute hysteresis value to a 4 bit delta value */
 267         limit = ADT7410_REG_TO_TEMP(data, data->temp[1]);
 268         hyst = clamp_val(hyst, ADT7410_TEMP_MIN, ADT7410_TEMP_MAX);
 269         data->hyst = clamp_val(DIV_ROUND_CLOSEST(limit - hyst, 1000), 0,
 270                                ADT7410_T_HYST_MASK);
 271         ret = i2c_smbus_write_byte_data(client, ADT7410_T_HYST, data->hyst);
 272         if (ret)
 273                 return ret;
 274
 275         return count;
 276 }
 277
 278 static ssize_t adt7410_show_alarm(struct device *dev,
 279                                   struct device_attribute *da,
 280                                   char *buf)
 281 {
 282         struct i2c_client *client = to_i2c_client(dev);
 283         struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
 284         int ret;
 285
 286         ret = i2c_smbus_read_byte_data(client, ADT7410_STATUS);
 287         if (ret < 0)
 288                 return ret;
 289
 290         return sprintf(buf, "%d\n", !!(ret & attr->index));
 291 }
 292
 293 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, adt7410_show_temp, NULL, 0);
 294 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
 295                           adt7410_show_temp, adt7410_set_temp, 1);
 296 static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO,
 297                           adt7410_show_temp, adt7410_set_temp, 2);
 298 static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO,
 299                           adt7410_show_temp, adt7410_set_temp, 3);
 300 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
 301                           adt7410_show_t_hyst, adt7410_set_t_hyst, 1);
 302 static SENSOR_DEVICE_ATTR(temp1_min_hyst, S_IRUGO,
 303                           adt7410_show_t_hyst, NULL, 2);
 304 static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IRUGO,
 305                           adt7410_show_t_hyst, NULL, 3);
 306 static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, adt7410_show_alarm,
 307                           NULL, ADT7410_STAT_T_LOW);
 308 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, adt7410_show_alarm,
 309                           NULL, ADT7410_STAT_T_HIGH);
 310 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, adt7410_show_alarm,
 311                           NULL, ADT7410_STAT_T_CRIT);
 312
 313 static struct attribute *adt7410_attributes[] = {
 314         &sensor_dev_attr_temp1_input.dev_attr.attr,
 315         &sensor_dev_attr_temp1_max.dev_attr.attr,
 316         &sensor_dev_attr_temp1_min.dev_attr.attr,
 317         &sensor_dev_attr_temp1_crit.dev_attr.attr,
 318         &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
 319         &sensor_dev_attr_temp1_min_hyst.dev_attr.attr,
 320         &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr,
 321         &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
 322         &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 323         &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
 324         NULL
 325 };
 326
 327 static const struct attribute_group adt7410_group = {
 328         .attrs = adt7410_attributes,
 329 };
 330
 331 /*-----------------------------------------------------------------------*/
 332
 333 /* device probe and removal */
 334
 335 static int adt7410_probe(struct i2c_client *client,
 336                          const struct i2c_device_id *id)
 337 {
 338         struct adt7410_data *data;
 339         int ret;
 340
 341         if (!i2c_check_functionality(client->adapter,
 342                         I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
 343                 return -ENODEV;
 344
 345         data = devm_kzalloc(&client->dev, sizeof(struct adt7410_data),
 346                             GFP_KERNEL);
 347         if (!data)
 348                 return -ENOMEM;
 349
 350         i2c_set_clientdata(client, data);
 351         mutex_init(&data->update_lock);
 352
 353         /* configure as specified */
 354         ret = i2c_smbus_read_byte_data(client, ADT7410_CONFIG);
 355         if (ret < 0) {
 356                 dev_dbg(&client->dev, "Can't read config? %d\n", ret);
 357                 return ret;
 358         }
 359         data->oldconfig = ret;
 360         /*
 361          * Set to 16 bit resolution, continous conversion and comparator mode.
 362          */
 363         ret &= ~ADT7410_MODE_MASK;
 364         data->config = ret | ADT7410_FULL | ADT7410_RESOLUTION |
 365                         ADT7410_EVENT_MODE;
 366         if (data->config != data->oldconfig) {
 367                 ret = i2c_smbus_write_byte_data(client, ADT7410_CONFIG,
 368                                                 data->config);
 369                 if (ret)
 370                         return ret;
 371         }
 372         dev_dbg(&client->dev, "Config %02x\n", data->config);
 373
 374         /* Register sysfs hooks */
 375         ret = sysfs_create_group(&client->dev.kobj, &adt7410_group);
 376         if (ret)
 377                 goto exit_restore;
 378
 379         data->hwmon_dev = hwmon_device_register(&client->dev);
 380         if (IS_ERR(data->hwmon_dev)) {
 381                 ret = PTR_ERR(data->hwmon_dev);
 382                 goto exit_remove;
 383         }
 384
 385         dev_info(&client->dev, "sensor '%s'\n", client->name);
 386
 387         return 0;
 388
 389 exit_remove:
 390         sysfs_remove_group(&client->dev.kobj, &adt7410_group);
 391 exit_restore:
 392         i2c_smbus_write_byte_data(client, ADT7410_CONFIG, data->oldconfig);
 393         return ret;
 394 }
 395
 396 static int adt7410_remove(struct i2c_client *client)
 397 {
 398         struct adt7410_data *data = i2c_get_clientdata(client);
 399
 400         hwmon_device_unregister(data->hwmon_dev);
 401         sysfs_remove_group(&client->dev.kobj, &adt7410_group);
 402         if (data->oldconfig != data->config)
 403                 i2c_smbus_write_byte_data(client, ADT7410_CONFIG,
 404                                           data->oldconfig);
 405         return 0;
 406 }
 407
 408 static const struct i2c_device_id adt7410_ids[] = {
 409         { "adt7410", adt7410, },
 410         { "adt7420", adt7410, },
 411         { /* LIST END */ }
 412 };
 413 MODULE_DEVICE_TABLE(i2c, adt7410_ids);
 414
 415 #ifdef CONFIG_PM_SLEEP
 416 static int adt7410_suspend(struct device *dev)
 417 {
 418         int ret;
 419         struct i2c_client *client = to_i2c_client(dev);
 420         struct adt7410_data *data = i2c_get_clientdata(client);
 421
 422         ret = i2c_smbus_write_byte_data(client, ADT7410_CONFIG,
 423                                         data->config | ADT7410_PD);
 424         return ret;
 425 }
 426
 427 static int adt7410_resume(struct device *dev)
 428 {
 429         int ret;
 430         struct i2c_client *client = to_i2c_client(dev);
 431         struct adt7410_data *data = i2c_get_clientdata(client);
 432
 433         ret = i2c_smbus_write_byte_data(client, ADT7410_CONFIG, data->config);
 434         return ret;
 435 }
 436
 437 static SIMPLE_DEV_PM_OPS(adt7410_dev_pm_ops, adt7410_suspend, adt7410_resume);
 438
 439 #define ADT7410_DEV_PM_OPS (&adt7410_dev_pm_ops)
 440 #else
 441 #define ADT7410_DEV_PM_OPS NULL
 442 #endif /* CONFIG_PM */
 443
 444 static struct i2c_driver adt7410_driver = {
 445         .class          = I2C_CLASS_HWMON,
 446         .driver = {
 447                 .name   = "adt7410",
 448                 .pm     = ADT7410_DEV_PM_OPS,
 449         },
 450         .probe          = adt7410_probe,
 451         .remove         = adt7410_remove,
 452         .id_table       = adt7410_ids,
 453         .address_list   = I2C_ADDRS(0x48, 0x49, 0x4a, 0x4b),
 454 };
 455
 456 module_i2c_driver(adt7410_driver);
 457
 458 MODULE_AUTHOR("Hartmut Knaack");
 459 MODULE_DESCRIPTION("ADT7410/ADT7420 driver");
 460 MODULE_LICENSE("GPL");