drivers/rtc/rtc-rv8803.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * RTC driver for the Micro Crystal RV8803
   4  *
   5  * Copyright (C) 2015 Micro Crystal SA
   6  * Alexandre Belloni <alexandre.belloni@bootlin.com>
   7  *
   8  */
   9
  10 #include <linux/bcd.h>
  11 #include <linux/bitops.h>
  12 #include <linux/log2.h>
  13 #include <linux/i2c.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/of_device.h>
  18 #include <linux/rtc.h>
  19
  20 #define RV8803_I2C_TRY_COUNT            4
  21
  22 #define RV8803_SEC                      0x00
  23 #define RV8803_MIN                      0x01
  24 #define RV8803_HOUR                     0x02
  25 #define RV8803_WEEK                     0x03
  26 #define RV8803_DAY                      0x04
  27 #define RV8803_MONTH                    0x05
  28 #define RV8803_YEAR                     0x06
  29 #define RV8803_RAM                      0x07
  30 #define RV8803_ALARM_MIN                0x08
  31 #define RV8803_ALARM_HOUR               0x09
  32 #define RV8803_ALARM_WEEK_OR_DAY        0x0A
  33 #define RV8803_EXT                      0x0D
  34 #define RV8803_FLAG                     0x0E
  35 #define RV8803_CTRL                     0x0F
  36
  37 #define RV8803_EXT_WADA                 BIT(6)
  38
  39 #define RV8803_FLAG_V1F                 BIT(0)
  40 #define RV8803_FLAG_V2F                 BIT(1)
  41 #define RV8803_FLAG_AF                  BIT(3)
  42 #define RV8803_FLAG_TF                  BIT(4)
  43 #define RV8803_FLAG_UF                  BIT(5)
  44
  45 #define RV8803_CTRL_RESET               BIT(0)
  46
  47 #define RV8803_CTRL_EIE                 BIT(2)
  48 #define RV8803_CTRL_AIE                 BIT(3)
  49 #define RV8803_CTRL_TIE                 BIT(4)
  50 #define RV8803_CTRL_UIE                 BIT(5)
  51
  52 #define RX8900_BACKUP_CTRL              0x18
  53 #define RX8900_FLAG_SWOFF               BIT(2)
  54 #define RX8900_FLAG_VDETOFF             BIT(3)
  55
  56 enum rv8803_type {
  57         rv_8803,
  58         rx_8900
  59 };
  60
  61 struct rv8803_data {
  62         struct i2c_client *client;
  63         struct rtc_device *rtc;
  64         struct mutex flags_lock;
  65         u8 ctrl;
  66         enum rv8803_type type;
  67 };
  68
  69 static int rv8803_read_reg(const struct i2c_client *client, u8 reg)
  70 {
  71         int try = RV8803_I2C_TRY_COUNT;
  72         s32 ret;
  73
  74         /*
  75          * There is a 61µs window during which the RTC does not acknowledge I2C
  76          * transfers. In that case, ensure that there are multiple attempts.
  77          */
  78         do
  79                 ret = i2c_smbus_read_byte_data(client, reg);
  80         while ((ret == -ENXIO || ret == -EIO) && --try);
  81         if (ret < 0)
  82                 dev_err(&client->dev, "Unable to read register 0x%02x\n", reg);
  83
  84         return ret;
  85 }
  86
  87 static int rv8803_read_regs(const struct i2c_client *client,
  88                             u8 reg, u8 count, u8 *values)
  89 {
  90         int try = RV8803_I2C_TRY_COUNT;
  91         s32 ret;
  92
  93         do
  94                 ret = i2c_smbus_read_i2c_block_data(client, reg, count, values);
  95         while ((ret == -ENXIO || ret == -EIO) && --try);
  96         if (ret != count) {
  97                 dev_err(&client->dev,
  98                         "Unable to read registers 0x%02x..0x%02x\n",
  99                         reg, reg + count - 1);
 100                 return ret < 0 ? ret : -EIO;
 101         }
 102
 103         return 0;
 104 }
 105
 106 static int rv8803_write_reg(const struct i2c_client *client, u8 reg, u8 value)
 107 {
 108         int try = RV8803_I2C_TRY_COUNT;
 109         s32 ret;
 110
 111         do
 112                 ret = i2c_smbus_write_byte_data(client, reg, value);
 113         while ((ret == -ENXIO || ret == -EIO) && --try);
 114         if (ret)
 115                 dev_err(&client->dev, "Unable to write register 0x%02x\n", reg);
 116
 117         return ret;
 118 }
 119
 120 static int rv8803_write_regs(const struct i2c_client *client,
 121                              u8 reg, u8 count, const u8 *values)
 122 {
 123         int try = RV8803_I2C_TRY_COUNT;
 124         s32 ret;
 125
 126         do
 127                 ret = i2c_smbus_write_i2c_block_data(client, reg, count,
 128                                                      values);
 129         while ((ret == -ENXIO || ret == -EIO) && --try);
 130         if (ret)
 131                 dev_err(&client->dev,
 132                         "Unable to write registers 0x%02x..0x%02x\n",
 133                         reg, reg + count - 1);
 134
 135         return ret;
 136 }
 137
 138 static irqreturn_t rv8803_handle_irq(int irq, void *dev_id)
 139 {
 140         struct i2c_client *client = dev_id;
 141         struct rv8803_data *rv8803 = i2c_get_clientdata(client);
 142         unsigned long events = 0;
 143         int flags;
 144
 145         mutex_lock(&rv8803->flags_lock);
 146
 147         flags = rv8803_read_reg(client, RV8803_FLAG);
 148         if (flags <= 0) {
 149                 mutex_unlock(&rv8803->flags_lock);
 150                 return IRQ_NONE;
 151         }
 152
 153         if (flags & RV8803_FLAG_V1F)
 154                 dev_warn(&client->dev, "Voltage low, temperature compensation stopped.\n");
 155
 156         if (flags & RV8803_FLAG_V2F)
 157                 dev_warn(&client->dev, "Voltage low, data loss detected.\n");
 158
 159         if (flags & RV8803_FLAG_TF) {
 160                 flags &= ~RV8803_FLAG_TF;
 161                 rv8803->ctrl &= ~RV8803_CTRL_TIE;
 162                 events |= RTC_PF;
 163         }
 164
 165         if (flags & RV8803_FLAG_AF) {
 166                 flags &= ~RV8803_FLAG_AF;
 167                 rv8803->ctrl &= ~RV8803_CTRL_AIE;
 168                 events |= RTC_AF;
 169         }
 170
 171         if (flags & RV8803_FLAG_UF) {
 172                 flags &= ~RV8803_FLAG_UF;
 173                 rv8803->ctrl &= ~RV8803_CTRL_UIE;
 174                 events |= RTC_UF;
 175         }
 176
 177         if (events) {
 178                 rtc_update_irq(rv8803->rtc, 1, events);
 179                 rv8803_write_reg(client, RV8803_FLAG, flags);
 180                 rv8803_write_reg(rv8803->client, RV8803_CTRL, rv8803->ctrl);
 181         }
 182
 183         mutex_unlock(&rv8803->flags_lock);
 184
 185         return IRQ_HANDLED;
 186 }
 187
 188 static int rv8803_get_time(struct device *dev, struct rtc_time *tm)
 189 {
 190         struct rv8803_data *rv8803 = dev_get_drvdata(dev);
 191         u8 date1[7];
 192         u8 date2[7];
 193         u8 *date = date1;
 194         int ret, flags;
 195
 196         flags = rv8803_read_reg(rv8803->client, RV8803_FLAG);
 197         if (flags < 0)
 198                 return flags;
 199
 200         if (flags & RV8803_FLAG_V2F) {
 201                 dev_warn(dev, "Voltage low, data is invalid.\n");
 202                 return -EINVAL;
 203         }
 204
 205         ret = rv8803_read_regs(rv8803->client, RV8803_SEC, 7, date);
 206         if (ret)
 207                 return ret;
 208
 209         if ((date1[RV8803_SEC] & 0x7f) == bin2bcd(59)) {
 210                 ret = rv8803_read_regs(rv8803->client, RV8803_SEC, 7, date2);
 211                 if (ret)
 212                         return ret;
 213
 214                 if ((date2[RV8803_SEC] & 0x7f) != bin2bcd(59))
 215                         date = date2;
 216         }
 217
 218         tm->tm_sec  = bcd2bin(date[RV8803_SEC] & 0x7f);
 219         tm->tm_min  = bcd2bin(date[RV8803_MIN] & 0x7f);
 220         tm->tm_hour = bcd2bin(date[RV8803_HOUR] & 0x3f);
 221         tm->tm_wday = ilog2(date[RV8803_WEEK] & 0x7f);
 222         tm->tm_mday = bcd2bin(date[RV8803_DAY] & 0x3f);
 223         tm->tm_mon  = bcd2bin(date[RV8803_MONTH] & 0x1f) - 1;
 224         tm->tm_year = bcd2bin(date[RV8803_YEAR]) + 100;
 225
 226         return 0;
 227 }
 228
 229 static int rv8803_set_time(struct device *dev, struct rtc_time *tm)
 230 {
 231         struct rv8803_data *rv8803 = dev_get_drvdata(dev);
 232         u8 date[7];
 233         int ctrl, flags, ret;
 234
 235         ctrl = rv8803_read_reg(rv8803->client, RV8803_CTRL);
 236         if (ctrl < 0)
 237                 return ctrl;
 238
 239         /* Stop the clock */
 240         ret = rv8803_write_reg(rv8803->client, RV8803_CTRL,
 241                                ctrl | RV8803_CTRL_RESET);
 242         if (ret)
 243                 return ret;
 244
 245         date[RV8803_SEC]   = bin2bcd(tm->tm_sec);
 246         date[RV8803_MIN]   = bin2bcd(tm->tm_min);
 247         date[RV8803_HOUR]  = bin2bcd(tm->tm_hour);
 248         date[RV8803_WEEK]  = 1 << (tm->tm_wday);
 249         date[RV8803_DAY]   = bin2bcd(tm->tm_mday);
 250         date[RV8803_MONTH] = bin2bcd(tm->tm_mon + 1);
 251         date[RV8803_YEAR]  = bin2bcd(tm->tm_year - 100);
 252
 253         ret = rv8803_write_regs(rv8803->client, RV8803_SEC, 7, date);
 254         if (ret)
 255                 return ret;
 256
 257         /* Restart the clock */
 258         ret = rv8803_write_reg(rv8803->client, RV8803_CTRL,
 259                                ctrl & ~RV8803_CTRL_RESET);
 260         if (ret)
 261                 return ret;
 262
 263         mutex_lock(&rv8803->flags_lock);
 264
 265         flags = rv8803_read_reg(rv8803->client, RV8803_FLAG);
 266         if (flags < 0) {
 267                 mutex_unlock(&rv8803->flags_lock);
 268                 return flags;
 269         }
 270
 271         ret = rv8803_write_reg(rv8803->client, RV8803_FLAG,
 272                                flags & ~(RV8803_FLAG_V1F | RV8803_FLAG_V2F));
 273
 274         mutex_unlock(&rv8803->flags_lock);
 275
 276         return ret;
 277 }
 278
 279 static int rv8803_get_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 280 {
 281         struct rv8803_data *rv8803 = dev_get_drvdata(dev);
 282         struct i2c_client *client = rv8803->client;
 283         u8 alarmvals[3];
 284         int flags, ret;
 285
 286         ret = rv8803_read_regs(client, RV8803_ALARM_MIN, 3, alarmvals);
 287         if (ret)
 288                 return ret;
 289
 290         flags = rv8803_read_reg(client, RV8803_FLAG);
 291         if (flags < 0)
 292                 return flags;
 293
 294         alrm->time.tm_sec  = 0;
 295         alrm->time.tm_min  = bcd2bin(alarmvals[0] & 0x7f);
 296         alrm->time.tm_hour = bcd2bin(alarmvals[1] & 0x3f);
 297         alrm->time.tm_mday = bcd2bin(alarmvals[2] & 0x3f);
 298
 299         alrm->enabled = !!(rv8803->ctrl & RV8803_CTRL_AIE);
 300         alrm->pending = (flags & RV8803_FLAG_AF) && alrm->enabled;
 301
 302         return 0;
 303 }
 304
 305 static int rv8803_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 306 {
 307         struct i2c_client *client = to_i2c_client(dev);
 308         struct rv8803_data *rv8803 = dev_get_drvdata(dev);
 309         u8 alarmvals[3];
 310         u8 ctrl[2];
 311         int ret, err;
 312
 313         /* The alarm has no seconds, round up to nearest minute */
 314         if (alrm->time.tm_sec) {
 315                 time64_t alarm_time = rtc_tm_to_time64(&alrm->time);
 316
 317                 alarm_time += 60 - alrm->time.tm_sec;
 318                 rtc_time64_to_tm(alarm_time, &alrm->time);
 319         }
 320
 321         mutex_lock(&rv8803->flags_lock);
 322
 323         ret = rv8803_read_regs(client, RV8803_FLAG, 2, ctrl);
 324         if (ret) {
 325                 mutex_unlock(&rv8803->flags_lock);
 326                 return ret;
 327         }
 328
 329         alarmvals[0] = bin2bcd(alrm->time.tm_min);
 330         alarmvals[1] = bin2bcd(alrm->time.tm_hour);
 331         alarmvals[2] = bin2bcd(alrm->time.tm_mday);
 332
 333         if (rv8803->ctrl & (RV8803_CTRL_AIE | RV8803_CTRL_UIE)) {
 334                 rv8803->ctrl &= ~(RV8803_CTRL_AIE | RV8803_CTRL_UIE);
 335                 err = rv8803_write_reg(rv8803->client, RV8803_CTRL,
 336                                        rv8803->ctrl);
 337                 if (err) {
 338                         mutex_unlock(&rv8803->flags_lock);
 339                         return err;
 340                 }
 341         }
 342
 343         ctrl[1] &= ~RV8803_FLAG_AF;
 344         err = rv8803_write_reg(rv8803->client, RV8803_FLAG, ctrl[1]);
 345         mutex_unlock(&rv8803->flags_lock);
 346         if (err)
 347                 return err;
 348
 349         err = rv8803_write_regs(rv8803->client, RV8803_ALARM_MIN, 3, alarmvals);
 350         if (err)
 351                 return err;
 352
 353         if (alrm->enabled) {
 354                 if (rv8803->rtc->uie_rtctimer.enabled)
 355                         rv8803->ctrl |= RV8803_CTRL_UIE;
 356                 if (rv8803->rtc->aie_timer.enabled)
 357                         rv8803->ctrl |= RV8803_CTRL_AIE;
 358
 359                 err = rv8803_write_reg(rv8803->client, RV8803_CTRL,
 360                                        rv8803->ctrl);
 361                 if (err)
 362                         return err;
 363         }
 364
 365         return 0;
 366 }
 367
 368 static int rv8803_alarm_irq_enable(struct device *dev, unsigned int enabled)
 369 {
 370         struct i2c_client *client = to_i2c_client(dev);
 371         struct rv8803_data *rv8803 = dev_get_drvdata(dev);
 372         int ctrl, flags, err;
 373
 374         ctrl = rv8803->ctrl;
 375
 376         if (enabled) {
 377                 if (rv8803->rtc->uie_rtctimer.enabled)
 378                         ctrl |= RV8803_CTRL_UIE;
 379                 if (rv8803->rtc->aie_timer.enabled)
 380                         ctrl |= RV8803_CTRL_AIE;
 381         } else {
 382                 if (!rv8803->rtc->uie_rtctimer.enabled)
 383                         ctrl &= ~RV8803_CTRL_UIE;
 384                 if (!rv8803->rtc->aie_timer.enabled)
 385                         ctrl &= ~RV8803_CTRL_AIE;
 386         }
 387
 388         mutex_lock(&rv8803->flags_lock);
 389         flags = rv8803_read_reg(client, RV8803_FLAG);
 390         if (flags < 0) {
 391                 mutex_unlock(&rv8803->flags_lock);
 392                 return flags;
 393         }
 394         flags &= ~(RV8803_FLAG_AF | RV8803_FLAG_UF);
 395         err = rv8803_write_reg(client, RV8803_FLAG, flags);
 396         mutex_unlock(&rv8803->flags_lock);
 397         if (err)
 398                 return err;
 399
 400         if (ctrl != rv8803->ctrl) {
 401                 rv8803->ctrl = ctrl;
 402                 err = rv8803_write_reg(client, RV8803_CTRL, rv8803->ctrl);
 403                 if (err)
 404                         return err;
 405         }
 406
 407         return 0;
 408 }
 409
 410 static int rv8803_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
 411 {
 412         struct i2c_client *client = to_i2c_client(dev);
 413         struct rv8803_data *rv8803 = dev_get_drvdata(dev);
 414         unsigned int vl = 0;
 415         int flags, ret = 0;
 416
 417         switch (cmd) {
 418         case RTC_VL_READ:
 419                 flags = rv8803_read_reg(client, RV8803_FLAG);
 420                 if (flags < 0)
 421                         return flags;
 422
 423                 if (flags & RV8803_FLAG_V1F) {
 424                         dev_warn(&client->dev, "Voltage low, temperature compensation stopped.\n");
 425                         vl = RTC_VL_ACCURACY_LOW;
 426                 }
 427
 428                 if (flags & RV8803_FLAG_V2F)
 429                         vl |= RTC_VL_DATA_INVALID;
 430
 431                 return put_user(vl, (unsigned int __user *)arg);
 432
 433         case RTC_VL_CLR:
 434                 mutex_lock(&rv8803->flags_lock);
 435                 flags = rv8803_read_reg(client, RV8803_FLAG);
 436                 if (flags < 0) {
 437                         mutex_unlock(&rv8803->flags_lock);
 438                         return flags;
 439                 }
 440
 441                 flags &= ~RV8803_FLAG_V1F;
 442                 ret = rv8803_write_reg(client, RV8803_FLAG, flags);
 443                 mutex_unlock(&rv8803->flags_lock);
 444                 if (ret)
 445                         return ret;
 446
 447                 return 0;
 448
 449         default:
 450                 return -ENOIOCTLCMD;
 451         }
 452 }
 453
 454 static int rv8803_nvram_write(void *priv, unsigned int offset, void *val,
 455                               size_t bytes)
 456 {
 457         return rv8803_write_reg(priv, RV8803_RAM, *(u8 *)val);
 458 }
 459
 460 static int rv8803_nvram_read(void *priv, unsigned int offset,
 461                              void *val, size_t bytes)
 462 {
 463         int ret;
 464
 465         ret = rv8803_read_reg(priv, RV8803_RAM);
 466         if (ret < 0)
 467                 return ret;
 468
 469         *(u8 *)val = ret;
 470
 471         return 0;
 472 }
 473
 474 static struct rtc_class_ops rv8803_rtc_ops = {
 475         .read_time = rv8803_get_time,
 476         .set_time = rv8803_set_time,
 477         .ioctl = rv8803_ioctl,
 478 };
 479
 480 static int rx8900_trickle_charger_init(struct rv8803_data *rv8803)
 481 {
 482         struct i2c_client *client = rv8803->client;
 483         struct device_node *node = client->dev.of_node;
 484         int err;
 485         u8 flags;
 486
 487         if (!node)
 488                 return 0;
 489
 490         if (rv8803->type != rx_8900)
 491                 return 0;
 492
 493         err = i2c_smbus_read_byte_data(rv8803->client, RX8900_BACKUP_CTRL);
 494         if (err < 0)
 495                 return err;
 496
 497         flags = ~(RX8900_FLAG_VDETOFF | RX8900_FLAG_SWOFF) & (u8)err;
 498
 499         if (of_property_read_bool(node, "epson,vdet-disable"))
 500                 flags |= RX8900_FLAG_VDETOFF;
 501
 502         if (of_property_read_bool(node, "trickle-diode-disable"))
 503                 flags |= RX8900_FLAG_SWOFF;
 504
 505         return i2c_smbus_write_byte_data(rv8803->client, RX8900_BACKUP_CTRL,
 506                                          flags);
 507 }
 508
 509 static int rv8803_probe(struct i2c_client *client,
 510                         const struct i2c_device_id *id)
 511 {
 512         struct i2c_adapter *adapter = client->adapter;
 513         struct rv8803_data *rv8803;
 514         int err, flags;
 515         struct nvmem_config nvmem_cfg = {
 516                 .name = "rv8803_nvram",
 517                 .word_size = 1,
 518                 .stride = 1,
 519                 .size = 1,
 520                 .reg_read = rv8803_nvram_read,
 521                 .reg_write = rv8803_nvram_write,
 522                 .priv = client,
 523         };
 524
 525         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
 526                                      I2C_FUNC_SMBUS_I2C_BLOCK)) {
 527                 dev_err(&adapter->dev, "doesn't support I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK\n");
 528                 return -EIO;
 529         }
 530
 531         rv8803 = devm_kzalloc(&client->dev, sizeof(struct rv8803_data),
 532                               GFP_KERNEL);
 533         if (!rv8803)
 534                 return -ENOMEM;
 535
 536         mutex_init(&rv8803->flags_lock);
 537         rv8803->client = client;
 538         if (client->dev.of_node)
 539                 rv8803->type = (enum rv8803_type)
 540                         of_device_get_match_data(&client->dev);
 541         else
 542                 rv8803->type = id->driver_data;
 543         i2c_set_clientdata(client, rv8803);
 544
 545         flags = rv8803_read_reg(client, RV8803_FLAG);
 546         if (flags < 0)
 547                 return flags;
 548
 549         if (flags & RV8803_FLAG_V1F)
 550                 dev_warn(&client->dev, "Voltage low, temperature compensation stopped.\n");
 551
 552         if (flags & RV8803_FLAG_V2F)
 553                 dev_warn(&client->dev, "Voltage low, data loss detected.\n");
 554
 555         if (flags & RV8803_FLAG_AF)
 556                 dev_warn(&client->dev, "An alarm maybe have been missed.\n");
 557
 558         rv8803->rtc = devm_rtc_allocate_device(&client->dev);
 559         if (IS_ERR(rv8803->rtc))
 560                 return PTR_ERR(rv8803->rtc);
 561
 562         if (client->irq > 0) {
 563                 err = devm_request_threaded_irq(&client->dev, client->irq,
 564                                                 NULL, rv8803_handle_irq,
 565                                                 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
 566                                                 "rv8803", client);
 567                 if (err) {
 568                         dev_warn(&client->dev, "unable to request IRQ, alarms disabled\n");
 569                         client->irq = 0;
 570                 } else {
 571                         rv8803_rtc_ops.read_alarm = rv8803_get_alarm;
 572                         rv8803_rtc_ops.set_alarm = rv8803_set_alarm;
 573                         rv8803_rtc_ops.alarm_irq_enable = rv8803_alarm_irq_enable;
 574                 }
 575         }
 576
 577         err = rv8803_write_reg(rv8803->client, RV8803_EXT, RV8803_EXT_WADA);
 578         if (err)
 579                 return err;
 580
 581         err = rx8900_trickle_charger_init(rv8803);
 582         if (err) {
 583                 dev_err(&client->dev, "failed to init charger\n");
 584                 return err;
 585         }
 586
 587         rv8803->rtc->ops = &rv8803_rtc_ops;
 588         rv8803->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 589         rv8803->rtc->range_max = RTC_TIMESTAMP_END_2099;
 590         err = devm_rtc_register_device(rv8803->rtc);
 591         if (err)
 592                 return err;
 593
 594         devm_rtc_nvmem_register(rv8803->rtc, &nvmem_cfg);
 595
 596         rv8803->rtc->max_user_freq = 1;
 597
 598         return 0;
 599 }
 600
 601 static const struct i2c_device_id rv8803_id[] = {
 602         { "rv8803", rv_8803 },
 603         { "rx8803", rv_8803 },
 604         { "rx8900", rx_8900 },
 605         { }
 606 };
 607 MODULE_DEVICE_TABLE(i2c, rv8803_id);
 608
 609 static const struct of_device_id rv8803_of_match[] = {
 610         {
 611                 .compatible = "microcrystal,rv8803",
 612                 .data = (void *)rv_8803
 613         },
 614         {
 615                 .compatible = "epson,rx8803",
 616                 .data = (void *)rv_8803
 617         },
 618         {
 619                 .compatible = "epson,rx8900",
 620                 .data = (void *)rx_8900
 621         },
 622         { }
 623 };
 624 MODULE_DEVICE_TABLE(of, rv8803_of_match);
 625
 626 static struct i2c_driver rv8803_driver = {
 627         .driver = {
 628                 .name = "rtc-rv8803",
 629                 .of_match_table = of_match_ptr(rv8803_of_match),
 630         },
 631         .probe          = rv8803_probe,
 632         .id_table       = rv8803_id,
 633 };
 634 module_i2c_driver(rv8803_driver);
 635
 636 MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>");
 637 MODULE_DESCRIPTION("Micro Crystal RV8803 RTC driver");
 638 MODULE_LICENSE("GPL v2");