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/bitops.h>
  26 #include <linux/module.h>
  27 #include <linux/init.h>
  28 #include <linux/slab.h>
  29 #include <linux/jiffies.h>
  30 #include <linux/i2c.h>
  31 #include <linux/hwmon.h>
  32 #include <linux/err.h>
  33 #include <linux/mutex.h>
  34 #include <linux/of.h>
  35
  36 /* Addresses to scan */
  37 static const unsigned short normal_i2c[] = {
  38         0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, I2C_CLIENT_END };
  39
  40 /* JC42 registers. All registers are 16 bit. */
  41 #define JC42_REG_CAP            0x00
  42 #define JC42_REG_CONFIG         0x01
  43 #define JC42_REG_TEMP_UPPER     0x02
  44 #define JC42_REG_TEMP_LOWER     0x03
  45 #define JC42_REG_TEMP_CRITICAL  0x04
  46 #define JC42_REG_TEMP           0x05
  47 #define JC42_REG_MANID          0x06
  48 #define JC42_REG_DEVICEID       0x07
  49 #define JC42_REG_SMBUS          0x22 /* NXP and Atmel, possibly others? */
  50
  51 /* Status bits in temperature register */
  52 #define JC42_ALARM_CRIT_BIT     15
  53 #define JC42_ALARM_MAX_BIT      14
  54 #define JC42_ALARM_MIN_BIT      13
  55
  56 /* Configuration register defines */
  57 #define JC42_CFG_CRIT_ONLY      (1 << 2)
  58 #define JC42_CFG_TCRIT_LOCK     (1 << 6)
  59 #define JC42_CFG_EVENT_LOCK     (1 << 7)
  60 #define JC42_CFG_SHUTDOWN       (1 << 8)
  61 #define JC42_CFG_HYST_SHIFT     9
  62 #define JC42_CFG_HYST_MASK      (0x03 << 9)
  63
  64 /* Capabilities */
  65 #define JC42_CAP_RANGE          (1 << 2)
  66
  67 /* Manufacturer IDs */
  68 #define ADT_MANID               0x11d4  /* Analog Devices */
  69 #define ATMEL_MANID             0x001f  /* Atmel */
  70 #define ATMEL_MANID2            0x1114  /* Atmel */
  71 #define MAX_MANID               0x004d  /* Maxim */
  72 #define IDT_MANID               0x00b3  /* IDT */
  73 #define MCP_MANID               0x0054  /* Microchip */
  74 #define NXP_MANID               0x1131  /* NXP Semiconductors */
  75 #define ONS_MANID               0x1b09  /* ON Semiconductor */
  76 #define STM_MANID               0x104a  /* ST Microelectronics */
  77 #define GT_MANID                0x1c68  /* Giantec */
  78 #define GT_MANID2               0x132d  /* Giantec, 2nd mfg ID */
  79
  80 /* SMBUS register */
  81 #define SMBUS_STMOUT            BIT(7)  /* SMBus time-out, active low */
  82
  83 /* Supported chips */
  84
  85 /* Analog Devices */
  86 #define ADT7408_DEVID           0x0801
  87 #define ADT7408_DEVID_MASK      0xffff
  88
  89 /* Atmel */
  90 #define AT30TS00_DEVID          0x8201
  91 #define AT30TS00_DEVID_MASK     0xffff
  92
  93 #define AT30TSE004_DEVID        0x2200
  94 #define AT30TSE004_DEVID_MASK   0xffff
  95
  96 /* Giantec */
  97 #define GT30TS00_DEVID          0x2200
  98 #define GT30TS00_DEVID_MASK     0xff00
  99
 100 #define GT34TS02_DEVID          0x3300
 101 #define GT34TS02_DEVID_MASK     0xff00
 102
 103 /* IDT */
 104 #define TSE2004_DEVID           0x2200
 105 #define TSE2004_DEVID_MASK      0xff00
 106
 107 #define TS3000_DEVID            0x2900  /* Also matches TSE2002 */
 108 #define TS3000_DEVID_MASK       0xff00
 109
 110 #define TS3001_DEVID            0x3000
 111 #define TS3001_DEVID_MASK       0xff00
 112
 113 /* Maxim */
 114 #define MAX6604_DEVID           0x3e00
 115 #define MAX6604_DEVID_MASK      0xffff
 116
 117 /* Microchip */
 118 #define MCP9804_DEVID           0x0200
 119 #define MCP9804_DEVID_MASK      0xfffc
 120
 121 #define MCP9808_DEVID           0x0400
 122 #define MCP9808_DEVID_MASK      0xfffc
 123
 124 #define MCP98242_DEVID          0x2000
 125 #define MCP98242_DEVID_MASK     0xfffc
 126
 127 #define MCP98243_DEVID          0x2100
 128 #define MCP98243_DEVID_MASK     0xfffc
 129
 130 #define MCP98244_DEVID          0x2200
 131 #define MCP98244_DEVID_MASK     0xfffc
 132
 133 #define MCP9843_DEVID           0x0000  /* Also matches mcp9805 */
 134 #define MCP9843_DEVID_MASK      0xfffe
 135
 136 /* NXP */
 137 #define SE97_DEVID              0xa200
 138 #define SE97_DEVID_MASK         0xfffc
 139
 140 #define SE98_DEVID              0xa100
 141 #define SE98_DEVID_MASK         0xfffc
 142
 143 /* ON Semiconductor */
 144 #define CAT6095_DEVID           0x0800  /* Also matches CAT34TS02 */
 145 #define CAT6095_DEVID_MASK      0xffe0
 146
 147 #define CAT34TS02C_DEVID        0x0a00
 148 #define CAT34TS02C_DEVID_MASK   0xfff0
 149
 150 #define CAT34TS04_DEVID         0x2200
 151 #define CAT34TS04_DEVID_MASK    0xfff0
 152
 153 /* ST Microelectronics */
 154 #define STTS424_DEVID           0x0101
 155 #define STTS424_DEVID_MASK      0xffff
 156
 157 #define STTS424E_DEVID          0x0000
 158 #define STTS424E_DEVID_MASK     0xfffe
 159
 160 #define STTS2002_DEVID          0x0300
 161 #define STTS2002_DEVID_MASK     0xffff
 162
 163 #define STTS2004_DEVID          0x2201
 164 #define STTS2004_DEVID_MASK     0xffff
 165
 166 #define STTS3000_DEVID          0x0200
 167 #define STTS3000_DEVID_MASK     0xffff
 168
 169 static u16 jc42_hysteresis[] = { 0, 1500, 3000, 6000 };
 170
 171 struct jc42_chips {
 172         u16 manid;
 173         u16 devid;
 174         u16 devid_mask;
 175 };
 176
 177 static struct jc42_chips jc42_chips[] = {
 178         { ADT_MANID, ADT7408_DEVID, ADT7408_DEVID_MASK },
 179         { ATMEL_MANID, AT30TS00_DEVID, AT30TS00_DEVID_MASK },
 180         { ATMEL_MANID2, AT30TSE004_DEVID, AT30TSE004_DEVID_MASK },
 181         { GT_MANID, GT30TS00_DEVID, GT30TS00_DEVID_MASK },
 182         { GT_MANID2, GT34TS02_DEVID, GT34TS02_DEVID_MASK },
 183         { IDT_MANID, TSE2004_DEVID, TSE2004_DEVID_MASK },
 184         { IDT_MANID, TS3000_DEVID, TS3000_DEVID_MASK },
 185         { IDT_MANID, TS3001_DEVID, TS3001_DEVID_MASK },
 186         { MAX_MANID, MAX6604_DEVID, MAX6604_DEVID_MASK },
 187         { MCP_MANID, MCP9804_DEVID, MCP9804_DEVID_MASK },
 188         { MCP_MANID, MCP9808_DEVID, MCP9808_DEVID_MASK },
 189         { MCP_MANID, MCP98242_DEVID, MCP98242_DEVID_MASK },
 190         { MCP_MANID, MCP98243_DEVID, MCP98243_DEVID_MASK },
 191         { MCP_MANID, MCP98244_DEVID, MCP98244_DEVID_MASK },
 192         { MCP_MANID, MCP9843_DEVID, MCP9843_DEVID_MASK },
 193         { NXP_MANID, SE97_DEVID, SE97_DEVID_MASK },
 194         { ONS_MANID, CAT6095_DEVID, CAT6095_DEVID_MASK },
 195         { ONS_MANID, CAT34TS02C_DEVID, CAT34TS02C_DEVID_MASK },
 196         { ONS_MANID, CAT34TS04_DEVID, CAT34TS04_DEVID_MASK },
 197         { NXP_MANID, SE98_DEVID, SE98_DEVID_MASK },
 198         { STM_MANID, STTS424_DEVID, STTS424_DEVID_MASK },
 199         { STM_MANID, STTS424E_DEVID, STTS424E_DEVID_MASK },
 200         { STM_MANID, STTS2002_DEVID, STTS2002_DEVID_MASK },
 201         { STM_MANID, STTS2004_DEVID, STTS2004_DEVID_MASK },
 202         { STM_MANID, STTS3000_DEVID, STTS3000_DEVID_MASK },
 203 };
 204
 205 enum temp_index {
 206         t_input = 0,
 207         t_crit,
 208         t_min,
 209         t_max,
 210         t_num_temp
 211 };
 212
 213 static const u8 temp_regs[t_num_temp] = {
 214         [t_input] = JC42_REG_TEMP,
 215         [t_crit] = JC42_REG_TEMP_CRITICAL,
 216         [t_min] = JC42_REG_TEMP_LOWER,
 217         [t_max] = JC42_REG_TEMP_UPPER,
 218 };
 219
 220 /* Each client has this additional data */
 221 struct jc42_data {
 222         struct i2c_client *client;
 223         struct mutex    update_lock;    /* protect register access */
 224         bool            extended;       /* true if extended range supported */
 225         bool            valid;
 226         unsigned long   last_updated;   /* In jiffies */
 227         u16             orig_config;    /* original configuration */
 228         u16             config;         /* current configuration */
 229         u16             temp[t_num_temp];/* Temperatures */
 230 };
 231
 232 #define JC42_TEMP_MIN_EXTENDED  (-40000)
 233 #define JC42_TEMP_MIN           0
 234 #define JC42_TEMP_MAX           125000
 235
 236 static u16 jc42_temp_to_reg(long temp, bool extended)
 237 {
 238         int ntemp = clamp_val(temp,
 239                               extended ? JC42_TEMP_MIN_EXTENDED :
 240                               JC42_TEMP_MIN, JC42_TEMP_MAX);
 241
 242         /* convert from 0.001 to 0.0625 resolution */
 243         return (ntemp * 2 / 125) & 0x1fff;
 244 }
 245
 246 static int jc42_temp_from_reg(s16 reg)
 247 {
 248         reg = sign_extend32(reg, 12);
 249
 250         /* convert from 0.0625 to 0.001 resolution */
 251         return reg * 125 / 2;
 252 }
 253
 254 static struct jc42_data *jc42_update_device(struct device *dev)
 255 {
 256         struct jc42_data *data = dev_get_drvdata(dev);
 257         struct i2c_client *client = data->client;
 258         struct jc42_data *ret = data;
 259         int i, val;
 260
 261         mutex_lock(&data->update_lock);
 262
 263         if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
 264                 for (i = 0; i < t_num_temp; i++) {
 265                         val = i2c_smbus_read_word_swapped(client, temp_regs[i]);
 266                         if (val < 0) {
 267                                 ret = ERR_PTR(val);
 268                                 goto abort;
 269                         }
 270                         data->temp[i] = val;
 271                 }
 272                 data->last_updated = jiffies;
 273                 data->valid = true;
 274         }
 275 abort:
 276         mutex_unlock(&data->update_lock);
 277         return ret;
 278 }
 279
 280 static int jc42_read(struct device *dev, enum hwmon_sensor_types type,
 281                      u32 attr, int channel, long *val)
 282 {
 283         struct jc42_data *data = jc42_update_device(dev);
 284         int temp, hyst;
 285
 286         if (IS_ERR(data))
 287                 return PTR_ERR(data);
 288
 289         switch (attr) {
 290         case hwmon_temp_input:
 291                 *val = jc42_temp_from_reg(data->temp[t_input]);
 292                 return 0;
 293         case hwmon_temp_min:
 294                 *val = jc42_temp_from_reg(data->temp[t_min]);
 295                 return 0;
 296         case hwmon_temp_max:
 297                 *val = jc42_temp_from_reg(data->temp[t_max]);
 298                 return 0;
 299         case hwmon_temp_crit:
 300                 *val = jc42_temp_from_reg(data->temp[t_crit]);
 301                 return 0;
 302         case hwmon_temp_max_hyst:
 303                 temp = jc42_temp_from_reg(data->temp[t_max]);
 304                 hyst = jc42_hysteresis[(data->config & JC42_CFG_HYST_MASK)
 305                                                 >> JC42_CFG_HYST_SHIFT];
 306                 *val = temp - hyst;
 307                 return 0;
 308         case hwmon_temp_crit_hyst:
 309                 temp = jc42_temp_from_reg(data->temp[t_crit]);
 310                 hyst = jc42_hysteresis[(data->config & JC42_CFG_HYST_MASK)
 311                                                 >> JC42_CFG_HYST_SHIFT];
 312                 *val = temp - hyst;
 313                 return 0;
 314         case hwmon_temp_min_alarm:
 315                 *val = (data->temp[t_input] >> JC42_ALARM_MIN_BIT) & 1;
 316                 return 0;
 317         case hwmon_temp_max_alarm:
 318                 *val = (data->temp[t_input] >> JC42_ALARM_MAX_BIT) & 1;
 319                 return 0;
 320         case hwmon_temp_crit_alarm:
 321                 *val = (data->temp[t_input] >> JC42_ALARM_CRIT_BIT) & 1;
 322                 return 0;
 323         default:
 324                 return -EOPNOTSUPP;
 325         }
 326 }
 327
 328 static int jc42_write(struct device *dev, enum hwmon_sensor_types type,
 329                       u32 attr, int channel, long val)
 330 {
 331         struct jc42_data *data = dev_get_drvdata(dev);
 332         struct i2c_client *client = data->client;
 333         int diff, hyst;
 334         int ret;
 335
 336         mutex_lock(&data->update_lock);
 337
 338         switch (attr) {
 339         case hwmon_temp_min:
 340                 data->temp[t_min] = jc42_temp_to_reg(val, data->extended);
 341                 ret = i2c_smbus_write_word_swapped(client, temp_regs[t_min],
 342                                                    data->temp[t_min]);
 343                 break;
 344         case hwmon_temp_max:
 345                 data->temp[t_max] = jc42_temp_to_reg(val, data->extended);
 346                 ret = i2c_smbus_write_word_swapped(client, temp_regs[t_max],
 347                                                    data->temp[t_max]);
 348                 break;
 349         case hwmon_temp_crit:
 350                 data->temp[t_crit] = jc42_temp_to_reg(val, data->extended);
 351                 ret = i2c_smbus_write_word_swapped(client, temp_regs[t_crit],
 352                                                    data->temp[t_crit]);
 353                 break;
 354         case hwmon_temp_crit_hyst:
 355                 /*
 356                  * JC42.4 compliant chips only support four hysteresis values.
 357                  * Pick best choice and go from there.
 358                  */
 359                 val = clamp_val(val, (data->extended ? JC42_TEMP_MIN_EXTENDED
 360                                                      : JC42_TEMP_MIN) - 6000,
 361                                 JC42_TEMP_MAX);
 362                 diff = jc42_temp_from_reg(data->temp[t_crit]) - val;
 363                 hyst = 0;
 364                 if (diff > 0) {
 365                         if (diff < 2250)
 366                                 hyst = 1;       /* 1.5 degrees C */
 367                         else if (diff < 4500)
 368                                 hyst = 2;       /* 3.0 degrees C */
 369                         else
 370                                 hyst = 3;       /* 6.0 degrees C */
 371                 }
 372                 data->config = (data->config & ~JC42_CFG_HYST_MASK) |
 373                                 (hyst << JC42_CFG_HYST_SHIFT);
 374                 ret = i2c_smbus_write_word_swapped(data->client,
 375                                                    JC42_REG_CONFIG,
 376                                                    data->config);
 377                 break;
 378         default:
 379                 ret = -EOPNOTSUPP;
 380                 break;
 381         }
 382
 383         mutex_unlock(&data->update_lock);
 384
 385         return ret;
 386 }
 387
 388 static umode_t jc42_is_visible(const void *_data, enum hwmon_sensor_types type,
 389                                u32 attr, int channel)
 390 {
 391         const struct jc42_data *data = _data;
 392         unsigned int config = data->config;
 393         umode_t mode = S_IRUGO;
 394
 395         switch (attr) {
 396         case hwmon_temp_min:
 397         case hwmon_temp_max:
 398                 if (!(config & JC42_CFG_EVENT_LOCK))
 399                         mode |= S_IWUSR;
 400                 break;
 401         case hwmon_temp_crit:
 402                 if (!(config & JC42_CFG_TCRIT_LOCK))
 403                         mode |= S_IWUSR;
 404                 break;
 405         case hwmon_temp_crit_hyst:
 406                 if (!(config & (JC42_CFG_EVENT_LOCK | JC42_CFG_TCRIT_LOCK)))
 407                         mode |= S_IWUSR;
 408                 break;
 409         case hwmon_temp_input:
 410         case hwmon_temp_max_hyst:
 411         case hwmon_temp_min_alarm:
 412         case hwmon_temp_max_alarm:
 413         case hwmon_temp_crit_alarm:
 414                 break;
 415         default:
 416                 mode = 0;
 417                 break;
 418         }
 419         return mode;
 420 }
 421
 422 /* Return 0 if detection is successful, -ENODEV otherwise */
 423 static int jc42_detect(struct i2c_client *client, struct i2c_board_info *info)
 424 {
 425         struct i2c_adapter *adapter = client->adapter;
 426         int i, config, cap, manid, devid;
 427
 428         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
 429                                      I2C_FUNC_SMBUS_WORD_DATA))
 430                 return -ENODEV;
 431
 432         cap = i2c_smbus_read_word_swapped(client, JC42_REG_CAP);
 433         config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG);
 434         manid = i2c_smbus_read_word_swapped(client, JC42_REG_MANID);
 435         devid = i2c_smbus_read_word_swapped(client, JC42_REG_DEVICEID);
 436
 437         if (cap < 0 || config < 0 || manid < 0 || devid < 0)
 438                 return -ENODEV;
 439
 440         if ((cap & 0xff00) || (config & 0xf800))
 441                 return -ENODEV;
 442
 443         for (i = 0; i < ARRAY_SIZE(jc42_chips); i++) {
 444                 struct jc42_chips *chip = &jc42_chips[i];
 445                 if (manid == chip->manid &&
 446                     (devid & chip->devid_mask) == chip->devid) {
 447                         strlcpy(info->type, "jc42", I2C_NAME_SIZE);
 448                         return 0;
 449                 }
 450         }
 451         return -ENODEV;
 452 }
 453
 454 static const u32 jc42_temp_config[] = {
 455         HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX | HWMON_T_CRIT |
 456         HWMON_T_MAX_HYST | HWMON_T_CRIT_HYST |
 457         HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM,
 458         0
 459 };
 460
 461 static const struct hwmon_channel_info jc42_temp = {
 462         .type = hwmon_temp,
 463         .config = jc42_temp_config,
 464 };
 465
 466 static const struct hwmon_channel_info *jc42_info[] = {
 467         &jc42_temp,
 468         NULL
 469 };
 470
 471 static const struct hwmon_ops jc42_hwmon_ops = {
 472         .is_visible = jc42_is_visible,
 473         .read = jc42_read,
 474         .write = jc42_write,
 475 };
 476
 477 static const struct hwmon_chip_info jc42_chip_info = {
 478         .ops = &jc42_hwmon_ops,
 479         .info = jc42_info,
 480 };
 481
 482 static int jc42_probe(struct i2c_client *client, const struct i2c_device_id *id)
 483 {
 484         struct device *dev = &client->dev;
 485         struct device *hwmon_dev;
 486         struct jc42_data *data;
 487         int config, cap;
 488
 489         data = devm_kzalloc(dev, sizeof(struct jc42_data), GFP_KERNEL);
 490         if (!data)
 491                 return -ENOMEM;
 492
 493         data->client = client;
 494         i2c_set_clientdata(client, data);
 495         mutex_init(&data->update_lock);
 496
 497         cap = i2c_smbus_read_word_swapped(client, JC42_REG_CAP);
 498         if (cap < 0)
 499                 return cap;
 500
 501         data->extended = !!(cap & JC42_CAP_RANGE);
 502
 503         if (device_property_read_bool(dev, "smbus-timeout-disable")) {
 504                 int smbus;
 505
 506                 /*
 507                  * Not all chips support this register, but from a
 508                  * quick read of various datasheets no chip appears
 509                  * incompatible with the below attempt to disable
 510                  * the timeout. And the whole thing is opt-in...
 511                  */
 512                 smbus = i2c_smbus_read_word_swapped(client, JC42_REG_SMBUS);
 513                 if (smbus < 0)
 514                         return smbus;
 515                 i2c_smbus_write_word_swapped(client, JC42_REG_SMBUS,
 516                                              smbus | SMBUS_STMOUT);
 517         }
 518
 519         config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG);
 520         if (config < 0)
 521                 return config;
 522
 523         data->orig_config = config;
 524         if (config & JC42_CFG_SHUTDOWN) {
 525                 config &= ~JC42_CFG_SHUTDOWN;
 526                 i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, config);
 527         }
 528         data->config = config;
 529
 530         hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
 531                                                          data, &jc42_chip_info,
 532                                                          NULL);
 533         return PTR_ERR_OR_ZERO(hwmon_dev);
 534 }
 535
 536 static int jc42_remove(struct i2c_client *client)
 537 {
 538         struct jc42_data *data = i2c_get_clientdata(client);
 539
 540         /* Restore original configuration except hysteresis */
 541         if ((data->config & ~JC42_CFG_HYST_MASK) !=
 542             (data->orig_config & ~JC42_CFG_HYST_MASK)) {
 543                 int config;
 544
 545                 config = (data->orig_config & ~JC42_CFG_HYST_MASK)
 546                   | (data->config & JC42_CFG_HYST_MASK);
 547                 i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, config);
 548         }
 549         return 0;
 550 }
 551
 552 #ifdef CONFIG_PM
 553
 554 static int jc42_suspend(struct device *dev)
 555 {
 556         struct jc42_data *data = dev_get_drvdata(dev);
 557
 558         data->config |= JC42_CFG_SHUTDOWN;
 559         i2c_smbus_write_word_swapped(data->client, JC42_REG_CONFIG,
 560                                      data->config);
 561         return 0;
 562 }
 563
 564 static int jc42_resume(struct device *dev)
 565 {
 566         struct jc42_data *data = dev_get_drvdata(dev);
 567
 568         data->config &= ~JC42_CFG_SHUTDOWN;
 569         i2c_smbus_write_word_swapped(data->client, JC42_REG_CONFIG,
 570                                      data->config);
 571         return 0;
 572 }
 573
 574 static const struct dev_pm_ops jc42_dev_pm_ops = {
 575         .suspend = jc42_suspend,
 576         .resume = jc42_resume,
 577 };
 578
 579 #define JC42_DEV_PM_OPS (&jc42_dev_pm_ops)
 580 #else
 581 #define JC42_DEV_PM_OPS NULL
 582 #endif /* CONFIG_PM */
 583
 584 static const struct i2c_device_id jc42_id[] = {
 585         { "jc42", 0 },
 586         { }
 587 };
 588 MODULE_DEVICE_TABLE(i2c, jc42_id);
 589
 590 #ifdef CONFIG_OF
 591 static const struct of_device_id jc42_of_ids[] = {
 592         { .compatible = "jedec,jc-42.4-temp", },
 593         { }
 594 };
 595 MODULE_DEVICE_TABLE(of, jc42_of_ids);
 596 #endif
 597
 598 static struct i2c_driver jc42_driver = {
 599         .class          = I2C_CLASS_SPD | I2C_CLASS_HWMON,
 600         .driver = {
 601                 .name   = "jc42",
 602                 .pm = JC42_DEV_PM_OPS,
 603                 .of_match_table = of_match_ptr(jc42_of_ids),
 604         },
 605         .probe          = jc42_probe,
 606         .remove         = jc42_remove,
 607         .id_table       = jc42_id,
 608         .detect         = jc42_detect,
 609         .address_list   = normal_i2c,
 610 };
 611
 612 module_i2c_driver(jc42_driver);
 613
 614 MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
 615 MODULE_DESCRIPTION("JC42 driver");
 616 MODULE_LICENSE("GPL");