drivers/hwmon/max1668.c

   1 /*
   2  * Copyright (c) 2011 David George <david.george@ska.ac.za>
   3  *
   4  * based on adm1021.c
   5  * some credit to Christoph Scheurer, but largely a rewrite
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/init.h>
  24 #include <linux/slab.h>
  25 #include <linux/jiffies.h>
  26 #include <linux/i2c.h>
  27 #include <linux/hwmon.h>
  28 #include <linux/hwmon-sysfs.h>
  29 #include <linux/err.h>
  30 #include <linux/mutex.h>
  31
  32 /* Addresses to scan */
  33 static unsigned short max1668_addr_list[] = {
  34         0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
  35
  36 /* max1668 registers */
  37
  38 #define MAX1668_REG_TEMP(nr)    (nr)
  39 #define MAX1668_REG_STAT1       0x05
  40 #define MAX1668_REG_STAT2       0x06
  41 #define MAX1668_REG_MAN_ID      0xfe
  42 #define MAX1668_REG_DEV_ID      0xff
  43
  44 /* limits */
  45
  46 /* write high limits */
  47 #define MAX1668_REG_LIMH_WR(nr) (0x13 + 2 * (nr))
  48 /* write low limits */
  49 #define MAX1668_REG_LIML_WR(nr) (0x14 + 2 * (nr))
  50 /* read high limits */
  51 #define MAX1668_REG_LIMH_RD(nr) (0x08 + 2 * (nr))
  52 /* read low limits */
  53 #define MAX1668_REG_LIML_RD(nr) (0x09 + 2 * (nr))
  54
  55 /* manufacturer and device ID Constants */
  56 #define MAN_ID_MAXIM            0x4d
  57 #define DEV_ID_MAX1668          0x3
  58 #define DEV_ID_MAX1805          0x5
  59 #define DEV_ID_MAX1989          0xb
  60
  61 /* read only mode module parameter */
  62 static bool read_only;
  63 module_param(read_only, bool, 0);
  64 MODULE_PARM_DESC(read_only, "Don't set any values, read only mode");
  65
  66 enum chips { max1668, max1805, max1989 };
  67
  68 struct max1668_data {
  69         struct device *hwmon_dev;
  70         enum chips type;
  71
  72         struct mutex update_lock;
  73         char valid;             /* !=0 if following fields are valid */
  74         unsigned long last_updated;     /* In jiffies */
  75
  76         /* 1x local and 4x remote */
  77         s8 temp_max[5];
  78         s8 temp_min[5];
  79         s8 temp[5];
  80         u16 alarms;
  81 };
  82
  83 static struct max1668_data *max1668_update_device(struct device *dev)
  84 {
  85         struct i2c_client *client = to_i2c_client(dev);
  86         struct max1668_data *data = i2c_get_clientdata(client);
  87         struct max1668_data *ret = data;
  88         s32 val;
  89         int i;
  90
  91         mutex_lock(&data->update_lock);
  92
  93         if (data->valid && !time_after(jiffies,
  94                         data->last_updated + HZ + HZ / 2))
  95                 goto abort;
  96
  97         for (i = 0; i < 5; i++) {
  98                 val = i2c_smbus_read_byte_data(client, MAX1668_REG_TEMP(i));
  99                 if (unlikely(val < 0)) {
 100                         ret = ERR_PTR(val);
 101                         goto abort;
 102                 }
 103                 data->temp[i] = (s8) val;
 104
 105                 val = i2c_smbus_read_byte_data(client, MAX1668_REG_LIMH_RD(i));
 106                 if (unlikely(val < 0)) {
 107                         ret = ERR_PTR(val);
 108                         goto abort;
 109                 }
 110                 data->temp_max[i] = (s8) val;
 111
 112                 val = i2c_smbus_read_byte_data(client, MAX1668_REG_LIML_RD(i));
 113                 if (unlikely(val < 0)) {
 114                         ret = ERR_PTR(val);
 115                         goto abort;
 116                 }
 117                 data->temp_min[i] = (s8) val;
 118         }
 119
 120         val = i2c_smbus_read_byte_data(client, MAX1668_REG_STAT1);
 121         if (unlikely(val < 0)) {
 122                 ret = ERR_PTR(val);
 123                 goto abort;
 124         }
 125         data->alarms = val << 8;
 126
 127         val = i2c_smbus_read_byte_data(client, MAX1668_REG_STAT2);
 128         if (unlikely(val < 0)) {
 129                 ret = ERR_PTR(val);
 130                 goto abort;
 131         }
 132         data->alarms |= val;
 133
 134         data->last_updated = jiffies;
 135         data->valid = 1;
 136 abort:
 137         mutex_unlock(&data->update_lock);
 138
 139         return ret;
 140 }
 141
 142 static ssize_t show_temp(struct device *dev,
 143                          struct device_attribute *devattr, char *buf)
 144 {
 145         int index = to_sensor_dev_attr(devattr)->index;
 146         struct max1668_data *data = max1668_update_device(dev);
 147
 148         if (IS_ERR(data))
 149                 return PTR_ERR(data);
 150
 151         return sprintf(buf, "%d\n", data->temp[index] * 1000);
 152 }
 153
 154 static ssize_t show_temp_max(struct device *dev,
 155                              struct device_attribute *devattr, char *buf)
 156 {
 157         int index = to_sensor_dev_attr(devattr)->index;
 158         struct max1668_data *data = max1668_update_device(dev);
 159
 160         if (IS_ERR(data))
 161                 return PTR_ERR(data);
 162
 163         return sprintf(buf, "%d\n", data->temp_max[index] * 1000);
 164 }
 165
 166 static ssize_t show_temp_min(struct device *dev,
 167                              struct device_attribute *devattr, char *buf)
 168 {
 169         int index = to_sensor_dev_attr(devattr)->index;
 170         struct max1668_data *data = max1668_update_device(dev);
 171
 172         if (IS_ERR(data))
 173                 return PTR_ERR(data);
 174
 175         return sprintf(buf, "%d\n", data->temp_min[index] * 1000);
 176 }
 177
 178 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
 179                           char *buf)
 180 {
 181         int index = to_sensor_dev_attr(attr)->index;
 182         struct max1668_data *data = max1668_update_device(dev);
 183
 184         if (IS_ERR(data))
 185                 return PTR_ERR(data);
 186
 187         return sprintf(buf, "%u\n", (data->alarms >> index) & 0x1);
 188 }
 189
 190 static ssize_t show_fault(struct device *dev,
 191                           struct device_attribute *devattr, char *buf)
 192 {
 193         int index = to_sensor_dev_attr(devattr)->index;
 194         struct max1668_data *data = max1668_update_device(dev);
 195
 196         if (IS_ERR(data))
 197                 return PTR_ERR(data);
 198
 199         return sprintf(buf, "%u\n",
 200                        (data->alarms & (1 << 12)) && data->temp[index] == 127);
 201 }
 202
 203 static ssize_t set_temp_max(struct device *dev,
 204                             struct device_attribute *devattr,
 205                             const char *buf, size_t count)
 206 {
 207         int index = to_sensor_dev_attr(devattr)->index;
 208         struct i2c_client *client = to_i2c_client(dev);
 209         struct max1668_data *data = i2c_get_clientdata(client);
 210         long temp;
 211         int ret;
 212
 213         ret = kstrtol(buf, 10, &temp);
 214         if (ret < 0)
 215                 return ret;
 216
 217         mutex_lock(&data->update_lock);
 218         data->temp_max[index] = clamp_val(temp/1000, -128, 127);
 219         if (i2c_smbus_write_byte_data(client,
 220                                         MAX1668_REG_LIMH_WR(index),
 221                                         data->temp_max[index]))
 222                 count = -EIO;
 223         mutex_unlock(&data->update_lock);
 224
 225         return count;
 226 }
 227
 228 static ssize_t set_temp_min(struct device *dev,
 229                             struct device_attribute *devattr,
 230                             const char *buf, size_t count)
 231 {
 232         int index = to_sensor_dev_attr(devattr)->index;
 233         struct i2c_client *client = to_i2c_client(dev);
 234         struct max1668_data *data = i2c_get_clientdata(client);
 235         long temp;
 236         int ret;
 237
 238         ret = kstrtol(buf, 10, &temp);
 239         if (ret < 0)
 240                 return ret;
 241
 242         mutex_lock(&data->update_lock);
 243         data->temp_min[index] = clamp_val(temp/1000, -128, 127);
 244         if (i2c_smbus_write_byte_data(client,
 245                                         MAX1668_REG_LIML_WR(index),
 246                                         data->temp_min[index]))
 247                 count = -EIO;
 248         mutex_unlock(&data->update_lock);
 249
 250         return count;
 251 }
 252
 253 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
 254 static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_temp_max,
 255                                 set_temp_max, 0);
 256 static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO, show_temp_min,
 257                                 set_temp_min, 0);
 258 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
 259 static SENSOR_DEVICE_ATTR(temp2_max, S_IRUGO, show_temp_max,
 260                                 set_temp_max, 1);
 261 static SENSOR_DEVICE_ATTR(temp2_min, S_IRUGO, show_temp_min,
 262                                 set_temp_min, 1);
 263 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
 264 static SENSOR_DEVICE_ATTR(temp3_max, S_IRUGO, show_temp_max,
 265                                 set_temp_max, 2);
 266 static SENSOR_DEVICE_ATTR(temp3_min, S_IRUGO, show_temp_min,
 267                                 set_temp_min, 2);
 268 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
 269 static SENSOR_DEVICE_ATTR(temp4_max, S_IRUGO, show_temp_max,
 270                                 set_temp_max, 3);
 271 static SENSOR_DEVICE_ATTR(temp4_min, S_IRUGO, show_temp_min,
 272                                 set_temp_min, 3);
 273 static SENSOR_DEVICE_ATTR(temp5_input, S_IRUGO, show_temp, NULL, 4);
 274 static SENSOR_DEVICE_ATTR(temp5_max, S_IRUGO, show_temp_max,
 275                                 set_temp_max, 4);
 276 static SENSOR_DEVICE_ATTR(temp5_min, S_IRUGO, show_temp_min,
 277                                 set_temp_min, 4);
 278
 279 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 14);
 280 static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 13);
 281 static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 7);
 282 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 6);
 283 static SENSOR_DEVICE_ATTR(temp3_min_alarm, S_IRUGO, show_alarm, NULL, 5);
 284 static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_alarm, NULL, 4);
 285 static SENSOR_DEVICE_ATTR(temp4_min_alarm, S_IRUGO, show_alarm, NULL, 3);
 286 static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_alarm, NULL, 2);
 287 static SENSOR_DEVICE_ATTR(temp5_min_alarm, S_IRUGO, show_alarm, NULL, 1);
 288 static SENSOR_DEVICE_ATTR(temp5_max_alarm, S_IRUGO, show_alarm, NULL, 0);
 289
 290 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_fault, NULL, 1);
 291 static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_fault, NULL, 2);
 292 static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_fault, NULL, 3);
 293 static SENSOR_DEVICE_ATTR(temp5_fault, S_IRUGO, show_fault, NULL, 4);
 294
 295 /* Attributes common to MAX1668, MAX1989 and MAX1805 */
 296 static struct attribute *max1668_attribute_common[] = {
 297         &sensor_dev_attr_temp1_max.dev_attr.attr,
 298         &sensor_dev_attr_temp1_min.dev_attr.attr,
 299         &sensor_dev_attr_temp1_input.dev_attr.attr,
 300         &sensor_dev_attr_temp2_max.dev_attr.attr,
 301         &sensor_dev_attr_temp2_min.dev_attr.attr,
 302         &sensor_dev_attr_temp2_input.dev_attr.attr,
 303         &sensor_dev_attr_temp3_max.dev_attr.attr,
 304         &sensor_dev_attr_temp3_min.dev_attr.attr,
 305         &sensor_dev_attr_temp3_input.dev_attr.attr,
 306
 307         &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 308         &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
 309         &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
 310         &sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
 311         &sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
 312         &sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
 313
 314         &sensor_dev_attr_temp2_fault.dev_attr.attr,
 315         &sensor_dev_attr_temp3_fault.dev_attr.attr,
 316         NULL
 317 };
 318
 319 /* Attributes not present on MAX1805 */
 320 static struct attribute *max1668_attribute_unique[] = {
 321         &sensor_dev_attr_temp4_max.dev_attr.attr,
 322         &sensor_dev_attr_temp4_min.dev_attr.attr,
 323         &sensor_dev_attr_temp4_input.dev_attr.attr,
 324         &sensor_dev_attr_temp5_max.dev_attr.attr,
 325         &sensor_dev_attr_temp5_min.dev_attr.attr,
 326         &sensor_dev_attr_temp5_input.dev_attr.attr,
 327
 328         &sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
 329         &sensor_dev_attr_temp4_min_alarm.dev_attr.attr,
 330         &sensor_dev_attr_temp5_max_alarm.dev_attr.attr,
 331         &sensor_dev_attr_temp5_min_alarm.dev_attr.attr,
 332
 333         &sensor_dev_attr_temp4_fault.dev_attr.attr,
 334         &sensor_dev_attr_temp5_fault.dev_attr.attr,
 335         NULL
 336 };
 337
 338 static umode_t max1668_attribute_mode(struct kobject *kobj,
 339                                      struct attribute *attr, int index)
 340 {
 341         umode_t ret = S_IRUGO;
 342         if (read_only)
 343                 return ret;
 344         if (attr == &sensor_dev_attr_temp1_max.dev_attr.attr ||
 345             attr == &sensor_dev_attr_temp2_max.dev_attr.attr ||
 346             attr == &sensor_dev_attr_temp3_max.dev_attr.attr ||
 347             attr == &sensor_dev_attr_temp4_max.dev_attr.attr ||
 348             attr == &sensor_dev_attr_temp5_max.dev_attr.attr ||
 349             attr == &sensor_dev_attr_temp1_min.dev_attr.attr ||
 350             attr == &sensor_dev_attr_temp2_min.dev_attr.attr ||
 351             attr == &sensor_dev_attr_temp3_min.dev_attr.attr ||
 352             attr == &sensor_dev_attr_temp4_min.dev_attr.attr ||
 353             attr == &sensor_dev_attr_temp5_min.dev_attr.attr)
 354                 ret |= S_IWUSR;
 355         return ret;
 356 }
 357
 358 static const struct attribute_group max1668_group_common = {
 359         .attrs = max1668_attribute_common,
 360         .is_visible = max1668_attribute_mode
 361 };
 362
 363 static const struct attribute_group max1668_group_unique = {
 364         .attrs = max1668_attribute_unique,
 365         .is_visible = max1668_attribute_mode
 366 };
 367
 368 /* Return 0 if detection is successful, -ENODEV otherwise */
 369 static int max1668_detect(struct i2c_client *client,
 370                           struct i2c_board_info *info)
 371 {
 372         struct i2c_adapter *adapter = client->adapter;
 373         const char *type_name;
 374         int man_id, dev_id;
 375
 376         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 377                 return -ENODEV;
 378
 379         /* Check for unsupported part */
 380         man_id = i2c_smbus_read_byte_data(client, MAX1668_REG_MAN_ID);
 381         if (man_id != MAN_ID_MAXIM)
 382                 return -ENODEV;
 383
 384         dev_id = i2c_smbus_read_byte_data(client, MAX1668_REG_DEV_ID);
 385         if (dev_id < 0)
 386                 return -ENODEV;
 387
 388         type_name = NULL;
 389         if (dev_id == DEV_ID_MAX1668)
 390                 type_name = "max1668";
 391         else if (dev_id == DEV_ID_MAX1805)
 392                 type_name = "max1805";
 393         else if (dev_id == DEV_ID_MAX1989)
 394                 type_name = "max1989";
 395
 396         if (!type_name)
 397                 return -ENODEV;
 398
 399         strlcpy(info->type, type_name, I2C_NAME_SIZE);
 400
 401         return 0;
 402 }
 403
 404 static int max1668_probe(struct i2c_client *client,
 405                          const struct i2c_device_id *id)
 406 {
 407         struct i2c_adapter *adapter = client->adapter;
 408         struct max1668_data *data;
 409         int err;
 410
 411         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 412                 return -ENODEV;
 413
 414         data = devm_kzalloc(&client->dev, sizeof(struct max1668_data),
 415                             GFP_KERNEL);
 416         if (!data)
 417                 return -ENOMEM;
 418
 419         i2c_set_clientdata(client, data);
 420         data->type = id->driver_data;
 421         mutex_init(&data->update_lock);
 422
 423         /* Register sysfs hooks */
 424         err = sysfs_create_group(&client->dev.kobj, &max1668_group_common);
 425         if (err)
 426                 return err;
 427
 428         if (data->type == max1668 || data->type == max1989) {
 429                 err = sysfs_create_group(&client->dev.kobj,
 430                                          &max1668_group_unique);
 431                 if (err)
 432                         goto error_sysrem0;
 433         }
 434
 435         data->hwmon_dev = hwmon_device_register(&client->dev);
 436         if (IS_ERR(data->hwmon_dev)) {
 437                 err = PTR_ERR(data->hwmon_dev);
 438                 goto error_sysrem1;
 439         }
 440
 441         return 0;
 442
 443 error_sysrem1:
 444         if (data->type == max1668 || data->type == max1989)
 445                 sysfs_remove_group(&client->dev.kobj, &max1668_group_unique);
 446 error_sysrem0:
 447         sysfs_remove_group(&client->dev.kobj, &max1668_group_common);
 448         return err;
 449 }
 450
 451 static int max1668_remove(struct i2c_client *client)
 452 {
 453         struct max1668_data *data = i2c_get_clientdata(client);
 454
 455         hwmon_device_unregister(data->hwmon_dev);
 456         if (data->type == max1668 || data->type == max1989)
 457                 sysfs_remove_group(&client->dev.kobj, &max1668_group_unique);
 458
 459         sysfs_remove_group(&client->dev.kobj, &max1668_group_common);
 460
 461         return 0;
 462 }
 463
 464 static const struct i2c_device_id max1668_id[] = {
 465         { "max1668", max1668 },
 466         { "max1805", max1805 },
 467         { "max1989", max1989 },
 468         { }
 469 };
 470 MODULE_DEVICE_TABLE(i2c, max1668_id);
 471
 472 /* This is the driver that will be inserted */
 473 static struct i2c_driver max1668_driver = {
 474         .class = I2C_CLASS_HWMON,
 475         .driver = {
 476                   .name = "max1668",
 477                   },
 478         .probe = max1668_probe,
 479         .remove = max1668_remove,
 480         .id_table = max1668_id,
 481         .detect = max1668_detect,
 482         .address_list = max1668_addr_list,
 483 };
 484
 485 module_i2c_driver(max1668_driver);
 486
 487 MODULE_AUTHOR("David George <david.george@ska.ac.za>");
 488 MODULE_DESCRIPTION("MAX1668 remote temperature sensor driver");
 489 MODULE_LICENSE("GPL");