drivers/hwmon/jc42.c

   1 /*
   2  * jc42.c - driver for Jedec JC42.4 compliant temperature sensors
   3  *
   4  * Copyright (c) 2010  Ericsson AB.
   5  *
   6  * Derived from lm77.c by Andras BALI <drewie@freemail.hu>.
   7  *
   8  * JC42.4 compliant temperature sensors are typically used on memory modules.
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23  */
  24
  25 #include <linux/module.h>
  26 #include <linux/init.h>
  27 #include <linux/slab.h>
  28 #include <linux/jiffies.h>
  29 #include <linux/i2c.h>
  30 #include <linux/hwmon.h>
  31 #include <linux/hwmon-sysfs.h>
  32 #include <linux/err.h>
  33 #include <linux/mutex.h>
  34
  35 /* Addresses to scan */
  36 static const unsigned short normal_i2c[] = {
  37         0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, I2C_CLIENT_END };
  38
  39 /* JC42 registers. All registers are 16 bit. */
  40 #define JC42_REG_CAP            0x00
  41 #define JC42_REG_CONFIG         0x01
  42 #define JC42_REG_TEMP_UPPER     0x02
  43 #define JC42_REG_TEMP_LOWER     0x03
  44 #define JC42_REG_TEMP_CRITICAL  0x04
  45 #define JC42_REG_TEMP           0x05
  46 #define JC42_REG_MANID          0x06
  47 #define JC42_REG_DEVICEID       0x07
  48
  49 /* Status bits in temperature register */
  50 #define JC42_ALARM_CRIT_BIT     15
  51 #define JC42_ALARM_MAX_BIT      14
  52 #define JC42_ALARM_MIN_BIT      13
  53
  54 /* Configuration register defines */
  55 #define JC42_CFG_CRIT_ONLY      (1 << 2)
  56 #define JC42_CFG_TCRIT_LOCK     (1 << 6)
  57 #define JC42_CFG_EVENT_LOCK     (1 << 7)
  58 #define JC42_CFG_SHUTDOWN       (1 << 8)
  59 #define JC42_CFG_HYST_SHIFT     9
  60 #define JC42_CFG_HYST_MASK      (0x03 << 9)
  61
  62 /* Capabilities */
  63 #define JC42_CAP_RANGE          (1 << 2)
  64
  65 /* Manufacturer IDs */
  66 #define ADT_MANID               0x11d4  /* Analog Devices */
  67 #define ATMEL_MANID             0x001f  /* Atmel */
  68 #define MAX_MANID               0x004d  /* Maxim */
  69 #define IDT_MANID               0x00b3  /* IDT */
  70 #define MCP_MANID               0x0054  /* Microchip */
  71 #define NXP_MANID               0x1131  /* NXP Semiconductors */
  72 #define ONS_MANID               0x1b09  /* ON Semiconductor */
  73 #define STM_MANID               0x104a  /* ST Microelectronics */
  74
  75 /* Supported chips */
  76
  77 /* Analog Devices */
  78 #define ADT7408_DEVID           0x0801
  79 #define ADT7408_DEVID_MASK      0xffff
  80
  81 /* Atmel */
  82 #define AT30TS00_DEVID          0x8201
  83 #define AT30TS00_DEVID_MASK     0xffff
  84
  85 /* IDT */
  86 #define TS3000B3_DEVID          0x2903  /* Also matches TSE2002B3 */
  87 #define TS3000B3_DEVID_MASK     0xffff
  88
  89 #define TS3000GB2_DEVID         0x2912  /* Also matches TSE2002GB2 */
  90 #define TS3000GB2_DEVID_MASK    0xffff
  91
  92 /* Maxim */
  93 #define MAX6604_DEVID           0x3e00
  94 #define MAX6604_DEVID_MASK      0xffff
  95
  96 /* Microchip */
  97 #define MCP9804_DEVID           0x0200
  98 #define MCP9804_DEVID_MASK      0xfffc
  99
 100 #define MCP98242_DEVID          0x2000
 101 #define MCP98242_DEVID_MASK     0xfffc
 102
 103 #define MCP98243_DEVID          0x2100
 104 #define MCP98243_DEVID_MASK     0xfffc
 105
 106 #define MCP98244_DEVID          0x2200
 107 #define MCP98244_DEVID_MASK     0xfffc
 108
 109 #define MCP9843_DEVID           0x0000  /* Also matches mcp9805 */
 110 #define MCP9843_DEVID_MASK      0xfffe
 111
 112 /* NXP */
 113 #define SE97_DEVID              0xa200
 114 #define SE97_DEVID_MASK         0xfffc
 115
 116 #define SE98_DEVID              0xa100
 117 #define SE98_DEVID_MASK         0xfffc
 118
 119 /* ON Semiconductor */
 120 #define CAT6095_DEVID           0x0800  /* Also matches CAT34TS02 */
 121 #define CAT6095_DEVID_MASK      0xffe0
 122
 123 /* ST Microelectronics */
 124 #define STTS424_DEVID           0x0101
 125 #define STTS424_DEVID_MASK      0xffff
 126
 127 #define STTS424E_DEVID          0x0000
 128 #define STTS424E_DEVID_MASK     0xfffe
 129
 130 #define STTS2002_DEVID          0x0300
 131 #define STTS2002_DEVID_MASK     0xffff
 132
 133 #define STTS3000_DEVID          0x0200
 134 #define STTS3000_DEVID_MASK     0xffff
 135
 136 static u16 jc42_hysteresis[] = { 0, 1500, 3000, 6000 };
 137
 138 struct jc42_chips {
 139         u16 manid;
 140         u16 devid;
 141         u16 devid_mask;
 142 };
 143
 144 static struct jc42_chips jc42_chips[] = {
 145         { ADT_MANID, ADT7408_DEVID, ADT7408_DEVID_MASK },
 146         { ATMEL_MANID, AT30TS00_DEVID, AT30TS00_DEVID_MASK },
 147         { IDT_MANID, TS3000B3_DEVID, TS3000B3_DEVID_MASK },
 148         { IDT_MANID, TS3000GB2_DEVID, TS3000GB2_DEVID_MASK },
 149         { MAX_MANID, MAX6604_DEVID, MAX6604_DEVID_MASK },
 150         { MCP_MANID, MCP9804_DEVID, MCP9804_DEVID_MASK },
 151         { MCP_MANID, MCP98242_DEVID, MCP98242_DEVID_MASK },
 152         { MCP_MANID, MCP98243_DEVID, MCP98243_DEVID_MASK },
 153         { MCP_MANID, MCP98244_DEVID, MCP98244_DEVID_MASK },
 154         { MCP_MANID, MCP9843_DEVID, MCP9843_DEVID_MASK },
 155         { NXP_MANID, SE97_DEVID, SE97_DEVID_MASK },
 156         { ONS_MANID, CAT6095_DEVID, CAT6095_DEVID_MASK },
 157         { NXP_MANID, SE98_DEVID, SE98_DEVID_MASK },
 158         { STM_MANID, STTS424_DEVID, STTS424_DEVID_MASK },
 159         { STM_MANID, STTS424E_DEVID, STTS424E_DEVID_MASK },
 160         { STM_MANID, STTS2002_DEVID, STTS2002_DEVID_MASK },
 161         { STM_MANID, STTS3000_DEVID, STTS3000_DEVID_MASK },
 162 };
 163
 164 /* Each client has this additional data */
 165 struct jc42_data {
 166         struct i2c_client *client;
 167         struct mutex    update_lock;    /* protect register access */
 168         bool            extended;       /* true if extended range supported */
 169         bool            valid;
 170         unsigned long   last_updated;   /* In jiffies */
 171         u16             orig_config;    /* original configuration */
 172         u16             config;         /* current configuration */
 173         u16             temp_input;     /* Temperatures */
 174         u16             temp_crit;
 175         u16             temp_min;
 176         u16             temp_max;
 177 };
 178
 179 static int jc42_probe(struct i2c_client *client,
 180                       const struct i2c_device_id *id);
 181 static int jc42_detect(struct i2c_client *client, struct i2c_board_info *info);
 182 static int jc42_remove(struct i2c_client *client);
 183
 184 static struct jc42_data *jc42_update_device(struct device *dev);
 185
 186 static const struct i2c_device_id jc42_id[] = {
 187         { "jc42", 0 },
 188         { }
 189 };
 190 MODULE_DEVICE_TABLE(i2c, jc42_id);
 191
 192 #ifdef CONFIG_PM
 193
 194 static int jc42_suspend(struct device *dev)
 195 {
 196         struct jc42_data *data = dev_get_drvdata(dev);
 197
 198         data->config |= JC42_CFG_SHUTDOWN;
 199         i2c_smbus_write_word_swapped(data->client, JC42_REG_CONFIG,
 200                                      data->config);
 201         return 0;
 202 }
 203
 204 static int jc42_resume(struct device *dev)
 205 {
 206         struct jc42_data *data = dev_get_drvdata(dev);
 207
 208         data->config &= ~JC42_CFG_SHUTDOWN;
 209         i2c_smbus_write_word_swapped(data->client, JC42_REG_CONFIG,
 210                                      data->config);
 211         return 0;
 212 }
 213
 214 static const struct dev_pm_ops jc42_dev_pm_ops = {
 215         .suspend = jc42_suspend,
 216         .resume = jc42_resume,
 217 };
 218
 219 #define JC42_DEV_PM_OPS (&jc42_dev_pm_ops)
 220 #else
 221 #define JC42_DEV_PM_OPS NULL
 222 #endif /* CONFIG_PM */
 223
 224 /* This is the driver that will be inserted */
 225 static struct i2c_driver jc42_driver = {
 226         .class          = I2C_CLASS_SPD,
 227         .driver = {
 228                 .name   = "jc42",
 229                 .pm = JC42_DEV_PM_OPS,
 230         },
 231         .probe          = jc42_probe,
 232         .remove         = jc42_remove,
 233         .id_table       = jc42_id,
 234         .detect         = jc42_detect,
 235         .address_list   = normal_i2c,
 236 };
 237
 238 #define JC42_TEMP_MIN_EXTENDED  (-40000)
 239 #define JC42_TEMP_MIN           0
 240 #define JC42_TEMP_MAX           125000
 241
 242 static u16 jc42_temp_to_reg(int temp, bool extended)
 243 {
 244         int ntemp = clamp_val(temp,
 245                               extended ? JC42_TEMP_MIN_EXTENDED :
 246                               JC42_TEMP_MIN, JC42_TEMP_MAX);
 247
 248         /* convert from 0.001 to 0.0625 resolution */
 249         return (ntemp * 2 / 125) & 0x1fff;
 250 }
 251
 252 static int jc42_temp_from_reg(s16 reg)
 253 {
 254         reg &= 0x1fff;
 255
 256         /* sign extend register */
 257         if (reg & 0x1000)
 258                 reg |= 0xf000;
 259
 260         /* convert from 0.0625 to 0.001 resolution */
 261         return reg * 125 / 2;
 262 }
 263
 264 /* sysfs stuff */
 265
 266 /* read routines for temperature limits */
 267 #define show(value)     \
 268 static ssize_t show_##value(struct device *dev,                         \
 269                             struct device_attribute *attr,              \
 270                             char *buf)                                  \
 271 {                                                                       \
 272         struct jc42_data *data = jc42_update_device(dev);               \
 273         if (IS_ERR(data))                                               \
 274                 return PTR_ERR(data);                                   \
 275         return sprintf(buf, "%d\n", jc42_temp_from_reg(data->value));   \
 276 }
 277
 278 show(temp_input);
 279 show(temp_crit);
 280 show(temp_min);
 281 show(temp_max);
 282
 283 /* read routines for hysteresis values */
 284 static ssize_t show_temp_crit_hyst(struct device *dev,
 285                                    struct device_attribute *attr, char *buf)
 286 {
 287         struct jc42_data *data = jc42_update_device(dev);
 288         int temp, hyst;
 289
 290         if (IS_ERR(data))
 291                 return PTR_ERR(data);
 292
 293         temp = jc42_temp_from_reg(data->temp_crit);
 294         hyst = jc42_hysteresis[(data->config & JC42_CFG_HYST_MASK)
 295                                >> JC42_CFG_HYST_SHIFT];
 296         return sprintf(buf, "%d\n", temp - hyst);
 297 }
 298
 299 static ssize_t show_temp_max_hyst(struct device *dev,
 300                                   struct device_attribute *attr, char *buf)
 301 {
 302         struct jc42_data *data = jc42_update_device(dev);
 303         int temp, hyst;
 304
 305         if (IS_ERR(data))
 306                 return PTR_ERR(data);
 307
 308         temp = jc42_temp_from_reg(data->temp_max);
 309         hyst = jc42_hysteresis[(data->config & JC42_CFG_HYST_MASK)
 310                                >> JC42_CFG_HYST_SHIFT];
 311         return sprintf(buf, "%d\n", temp - hyst);
 312 }
 313
 314 /* write routines */
 315 #define set(value, reg) \
 316 static ssize_t set_##value(struct device *dev,                          \
 317                            struct device_attribute *attr,               \
 318                            const char *buf, size_t count)               \
 319 {                                                                       \
 320         struct jc42_data *data = dev_get_drvdata(dev);                  \
 321         int err, ret = count;                                           \
 322         long val;                                                       \
 323         if (kstrtol(buf, 10, &val) < 0)                                 \
 324                 return -EINVAL;                                         \
 325         mutex_lock(&data->update_lock);                                 \
 326         data->value = jc42_temp_to_reg(val, data->extended);            \
 327         err = i2c_smbus_write_word_swapped(data->client, reg, data->value); \
 328         if (err < 0)                                                    \
 329                 ret = err;                                              \
 330         mutex_unlock(&data->update_lock);                               \
 331         return ret;                                                     \
 332 }
 333
 334 set(temp_min, JC42_REG_TEMP_LOWER);
 335 set(temp_max, JC42_REG_TEMP_UPPER);
 336 set(temp_crit, JC42_REG_TEMP_CRITICAL);
 337
 338 /*
 339  * JC42.4 compliant chips only support four hysteresis values.
 340  * Pick best choice and go from there.
 341  */
 342 static ssize_t set_temp_crit_hyst(struct device *dev,
 343                                   struct device_attribute *attr,
 344                                   const char *buf, size_t count)
 345 {
 346         struct jc42_data *data = dev_get_drvdata(dev);
 347         unsigned long val;
 348         int diff, hyst;
 349         int err;
 350         int ret = count;
 351
 352         if (kstrtoul(buf, 10, &val) < 0)
 353                 return -EINVAL;
 354
 355         diff = jc42_temp_from_reg(data->temp_crit) - val;
 356         hyst = 0;
 357         if (diff > 0) {
 358                 if (diff < 2250)
 359                         hyst = 1;       /* 1.5 degrees C */
 360                 else if (diff < 4500)
 361                         hyst = 2;       /* 3.0 degrees C */
 362                 else
 363                         hyst = 3;       /* 6.0 degrees C */
 364         }
 365
 366         mutex_lock(&data->update_lock);
 367         data->config = (data->config & ~JC42_CFG_HYST_MASK)
 368           | (hyst << JC42_CFG_HYST_SHIFT);
 369         err = i2c_smbus_write_word_swapped(data->client, JC42_REG_CONFIG,
 370                                            data->config);
 371         if (err < 0)
 372                 ret = err;
 373         mutex_unlock(&data->update_lock);
 374         return ret;
 375 }
 376
 377 static ssize_t show_alarm(struct device *dev,
 378                           struct device_attribute *attr, char *buf)
 379 {
 380         u16 bit = to_sensor_dev_attr(attr)->index;
 381         struct jc42_data *data = jc42_update_device(dev);
 382         u16 val;
 383
 384         if (IS_ERR(data))
 385                 return PTR_ERR(data);
 386
 387         val = data->temp_input;
 388         if (bit != JC42_ALARM_CRIT_BIT && (data->config & JC42_CFG_CRIT_ONLY))
 389                 val = 0;
 390         return sprintf(buf, "%u\n", (val >> bit) & 1);
 391 }
 392
 393 static DEVICE_ATTR(temp1_input, S_IRUGO,
 394                    show_temp_input, NULL);
 395 static DEVICE_ATTR(temp1_crit, S_IRUGO,
 396                    show_temp_crit, set_temp_crit);
 397 static DEVICE_ATTR(temp1_min, S_IRUGO,
 398                    show_temp_min, set_temp_min);
 399 static DEVICE_ATTR(temp1_max, S_IRUGO,
 400                    show_temp_max, set_temp_max);
 401
 402 static DEVICE_ATTR(temp1_crit_hyst, S_IRUGO,
 403                    show_temp_crit_hyst, set_temp_crit_hyst);
 404 static DEVICE_ATTR(temp1_max_hyst, S_IRUGO,
 405                    show_temp_max_hyst, NULL);
 406
 407 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL,
 408                           JC42_ALARM_CRIT_BIT);
 409 static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL,
 410                           JC42_ALARM_MIN_BIT);
 411 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL,
 412                           JC42_ALARM_MAX_BIT);
 413
 414 static struct attribute *jc42_attributes[] = {
 415         &dev_attr_temp1_input.attr,
 416         &dev_attr_temp1_crit.attr,
 417         &dev_attr_temp1_min.attr,
 418         &dev_attr_temp1_max.attr,
 419         &dev_attr_temp1_crit_hyst.attr,
 420         &dev_attr_temp1_max_hyst.attr,
 421         &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
 422         &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
 423         &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 424         NULL
 425 };
 426
 427 static umode_t jc42_attribute_mode(struct kobject *kobj,
 428                                   struct attribute *attr, int index)
 429 {
 430         struct device *dev = container_of(kobj, struct device, kobj);
 431         struct jc42_data *data = dev_get_drvdata(dev);
 432         unsigned int config = data->config;
 433         bool readonly;
 434
 435         if (attr == &dev_attr_temp1_crit.attr)
 436                 readonly = config & JC42_CFG_TCRIT_LOCK;
 437         else if (attr == &dev_attr_temp1_min.attr ||
 438                  attr == &dev_attr_temp1_max.attr)
 439                 readonly = config & JC42_CFG_EVENT_LOCK;
 440         else if (attr == &dev_attr_temp1_crit_hyst.attr)
 441                 readonly = config & (JC42_CFG_EVENT_LOCK | JC42_CFG_TCRIT_LOCK);
 442         else
 443                 readonly = true;
 444
 445         return S_IRUGO | (readonly ? 0 : S_IWUSR);
 446 }
 447
 448 static const struct attribute_group jc42_group = {
 449         .attrs = jc42_attributes,
 450         .is_visible = jc42_attribute_mode,
 451 };
 452 __ATTRIBUTE_GROUPS(jc42);
 453
 454 /* Return 0 if detection is successful, -ENODEV otherwise */
 455 static int jc42_detect(struct i2c_client *client, struct i2c_board_info *info)
 456 {
 457         struct i2c_adapter *adapter = client->adapter;
 458         int i, config, cap, manid, devid;
 459
 460         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
 461                                      I2C_FUNC_SMBUS_WORD_DATA))
 462                 return -ENODEV;
 463
 464         cap = i2c_smbus_read_word_swapped(client, JC42_REG_CAP);
 465         config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG);
 466         manid = i2c_smbus_read_word_swapped(client, JC42_REG_MANID);
 467         devid = i2c_smbus_read_word_swapped(client, JC42_REG_DEVICEID);
 468
 469         if (cap < 0 || config < 0 || manid < 0 || devid < 0)
 470                 return -ENODEV;
 471
 472         if ((cap & 0xff00) || (config & 0xf800))
 473                 return -ENODEV;
 474
 475         for (i = 0; i < ARRAY_SIZE(jc42_chips); i++) {
 476                 struct jc42_chips *chip = &jc42_chips[i];
 477                 if (manid == chip->manid &&
 478                     (devid & chip->devid_mask) == chip->devid) {
 479                         strlcpy(info->type, "jc42", I2C_NAME_SIZE);
 480                         return 0;
 481                 }
 482         }
 483         return -ENODEV;
 484 }
 485
 486 static int jc42_probe(struct i2c_client *client, const struct i2c_device_id *id)
 487 {
 488         struct device *dev = &client->dev;
 489         struct device *hwmon_dev;
 490         struct jc42_data *data;
 491         int config, cap;
 492
 493         data = devm_kzalloc(dev, sizeof(struct jc42_data), GFP_KERNEL);
 494         if (!data)
 495                 return -ENOMEM;
 496
 497         data->client = client;
 498         i2c_set_clientdata(client, data);
 499         mutex_init(&data->update_lock);
 500
 501         cap = i2c_smbus_read_word_swapped(client, JC42_REG_CAP);
 502         if (cap < 0)
 503                 return cap;
 504
 505         data->extended = !!(cap & JC42_CAP_RANGE);
 506
 507         config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG);
 508         if (config < 0)
 509                 return config;
 510
 511         data->orig_config = config;
 512         if (config & JC42_CFG_SHUTDOWN) {
 513                 config &= ~JC42_CFG_SHUTDOWN;
 514                 i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, config);
 515         }
 516         data->config = config;
 517
 518         hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
 519                                                            data,
 520                                                            jc42_groups);
 521         return PTR_ERR_OR_ZERO(hwmon_dev);
 522 }
 523
 524 static int jc42_remove(struct i2c_client *client)
 525 {
 526         struct jc42_data *data = i2c_get_clientdata(client);
 527
 528         /* Restore original configuration except hysteresis */
 529         if ((data->config & ~JC42_CFG_HYST_MASK) !=
 530             (data->orig_config & ~JC42_CFG_HYST_MASK)) {
 531                 int config;
 532
 533                 config = (data->orig_config & ~JC42_CFG_HYST_MASK)
 534                   | (data->config & JC42_CFG_HYST_MASK);
 535                 i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, config);
 536         }
 537         return 0;
 538 }
 539
 540 static struct jc42_data *jc42_update_device(struct device *dev)
 541 {
 542         struct jc42_data *data = dev_get_drvdata(dev);
 543         struct i2c_client *client = data->client;
 544         struct jc42_data *ret = data;
 545         int val;
 546
 547         mutex_lock(&data->update_lock);
 548
 549         if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
 550                 val = i2c_smbus_read_word_swapped(client, JC42_REG_TEMP);
 551                 if (val < 0) {
 552                         ret = ERR_PTR(val);
 553                         goto abort;
 554                 }
 555                 data->temp_input = val;
 556
 557                 val = i2c_smbus_read_word_swapped(client,
 558                                                   JC42_REG_TEMP_CRITICAL);
 559                 if (val < 0) {
 560                         ret = ERR_PTR(val);
 561                         goto abort;
 562                 }
 563                 data->temp_crit = val;
 564
 565                 val = i2c_smbus_read_word_swapped(client, JC42_REG_TEMP_LOWER);
 566                 if (val < 0) {
 567                         ret = ERR_PTR(val);
 568                         goto abort;
 569                 }
 570                 data->temp_min = val;
 571
 572                 val = i2c_smbus_read_word_swapped(client, JC42_REG_TEMP_UPPER);
 573                 if (val < 0) {
 574                         ret = ERR_PTR(val);
 575                         goto abort;
 576                 }
 577                 data->temp_max = val;
 578
 579                 data->last_updated = jiffies;
 580                 data->valid = true;
 581         }
 582 abort:
 583         mutex_unlock(&data->update_lock);
 584         return ret;
 585 }
 586
 587 module_i2c_driver(jc42_driver);
 588
 589 MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
 590 MODULE_DESCRIPTION("JC42 driver");
 591 MODULE_LICENSE("GPL");