linux/drivers/rtc/rtc-fm3130.c
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   1/*
   2 * rtc-fm3130.c - RTC driver for Ramtron FM3130 I2C chip.
   3 *
   4 *  Copyright (C) 2008 Sergey Lapin
   5 *  Based on ds1307 driver by James Chapman and David Brownell
   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 version 2 as
   9 * published by the Free Software Foundation.
  10 */
  11
  12#include <linux/module.h>
  13#include <linux/i2c.h>
  14#include <linux/rtc.h>
  15#include <linux/bcd.h>
  16#include <linux/slab.h>
  17
  18#define FM3130_RTC_CONTROL      (0x0)
  19#define FM3130_CAL_CONTROL      (0x1)
  20#define FM3130_RTC_SECONDS      (0x2)
  21#define FM3130_RTC_MINUTES      (0x3)
  22#define FM3130_RTC_HOURS        (0x4)
  23#define FM3130_RTC_DAY          (0x5)
  24#define FM3130_RTC_DATE         (0x6)
  25#define FM3130_RTC_MONTHS       (0x7)
  26#define FM3130_RTC_YEARS        (0x8)
  27
  28#define FM3130_ALARM_SECONDS    (0x9)
  29#define FM3130_ALARM_MINUTES    (0xa)
  30#define FM3130_ALARM_HOURS      (0xb)
  31#define FM3130_ALARM_DATE       (0xc)
  32#define FM3130_ALARM_MONTHS     (0xd)
  33#define FM3130_ALARM_WP_CONTROL (0xe)
  34
  35#define FM3130_CAL_CONTROL_BIT_nOSCEN (1 << 7) /* Osciallator enabled */
  36#define FM3130_RTC_CONTROL_BIT_LB (1 << 7) /* Low battery */
  37#define FM3130_RTC_CONTROL_BIT_AF (1 << 6) /* Alarm flag */
  38#define FM3130_RTC_CONTROL_BIT_CF (1 << 5) /* Century overflow */
  39#define FM3130_RTC_CONTROL_BIT_POR (1 << 4) /* Power on reset */
  40#define FM3130_RTC_CONTROL_BIT_AEN (1 << 3) /* Alarm enable */
  41#define FM3130_RTC_CONTROL_BIT_CAL (1 << 2) /* Calibration mode */
  42#define FM3130_RTC_CONTROL_BIT_WRITE (1 << 1) /* W=1 -> write mode W=0 normal */
  43#define FM3130_RTC_CONTROL_BIT_READ (1 << 0) /* R=1 -> read mode R=0 normal */
  44
  45#define FM3130_CLOCK_REGS 7
  46#define FM3130_ALARM_REGS 5
  47
  48struct fm3130 {
  49        u8                      reg_addr_time;
  50        u8                      reg_addr_alarm;
  51        u8                      regs[15];
  52        struct i2c_msg          msg[4];
  53        struct i2c_client       *client;
  54        struct rtc_device       *rtc;
  55        int                     alarm_valid;
  56        int                     data_valid;
  57};
  58static const struct i2c_device_id fm3130_id[] = {
  59        { "fm3130", 0 },
  60        { }
  61};
  62MODULE_DEVICE_TABLE(i2c, fm3130_id);
  63
  64#define FM3130_MODE_NORMAL              0
  65#define FM3130_MODE_WRITE               1
  66#define FM3130_MODE_READ                2
  67
  68static void fm3130_rtc_mode(struct device *dev, int mode)
  69{
  70        struct fm3130 *fm3130 = dev_get_drvdata(dev);
  71
  72        fm3130->regs[FM3130_RTC_CONTROL] =
  73                i2c_smbus_read_byte_data(fm3130->client, FM3130_RTC_CONTROL);
  74        switch (mode) {
  75        case FM3130_MODE_NORMAL:
  76                fm3130->regs[FM3130_RTC_CONTROL] &=
  77                        ~(FM3130_RTC_CONTROL_BIT_WRITE |
  78                        FM3130_RTC_CONTROL_BIT_READ);
  79                break;
  80        case FM3130_MODE_WRITE:
  81                fm3130->regs[FM3130_RTC_CONTROL] |= FM3130_RTC_CONTROL_BIT_WRITE;
  82                break;
  83        case FM3130_MODE_READ:
  84                fm3130->regs[FM3130_RTC_CONTROL] |= FM3130_RTC_CONTROL_BIT_READ;
  85                break;
  86        default:
  87                dev_dbg(dev, "invalid mode %d\n", mode);
  88                break;
  89        }
  90
  91        i2c_smbus_write_byte_data(fm3130->client,
  92                 FM3130_RTC_CONTROL, fm3130->regs[FM3130_RTC_CONTROL]);
  93}
  94
  95static int fm3130_get_time(struct device *dev, struct rtc_time *t)
  96{
  97        struct fm3130 *fm3130 = dev_get_drvdata(dev);
  98        int             tmp;
  99
 100        if (!fm3130->data_valid) {
 101                /* We have invalid data in RTC, probably due
 102                to battery faults or other problems. Return EIO
 103                for now, it will allow us to set data later instead
 104                of error during probing which disables device */
 105                return -EIO;
 106        }
 107        fm3130_rtc_mode(dev, FM3130_MODE_READ);
 108
 109        /* read the RTC date and time registers all at once */
 110        tmp = i2c_transfer(to_i2c_adapter(fm3130->client->dev.parent),
 111                        fm3130->msg, 2);
 112        if (tmp != 2) {
 113                dev_err(dev, "%s error %d\n", "read", tmp);
 114                return -EIO;
 115        }
 116
 117        fm3130_rtc_mode(dev, FM3130_MODE_NORMAL);
 118
 119        dev_dbg(dev, "%s: %15ph\n", "read", fm3130->regs);
 120
 121        t->tm_sec = bcd2bin(fm3130->regs[FM3130_RTC_SECONDS] & 0x7f);
 122        t->tm_min = bcd2bin(fm3130->regs[FM3130_RTC_MINUTES] & 0x7f);
 123        tmp = fm3130->regs[FM3130_RTC_HOURS] & 0x3f;
 124        t->tm_hour = bcd2bin(tmp);
 125        t->tm_wday = bcd2bin(fm3130->regs[FM3130_RTC_DAY] & 0x07) - 1;
 126        t->tm_mday = bcd2bin(fm3130->regs[FM3130_RTC_DATE] & 0x3f);
 127        tmp = fm3130->regs[FM3130_RTC_MONTHS] & 0x1f;
 128        t->tm_mon = bcd2bin(tmp) - 1;
 129
 130        /* assume 20YY not 19YY, and ignore CF bit */
 131        t->tm_year = bcd2bin(fm3130->regs[FM3130_RTC_YEARS]) + 100;
 132
 133        dev_dbg(dev, "%s secs=%d, mins=%d, "
 134                "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
 135                "read", t->tm_sec, t->tm_min,
 136                t->tm_hour, t->tm_mday,
 137                t->tm_mon, t->tm_year, t->tm_wday);
 138
 139        /* initial clock setting can be undefined */
 140        return rtc_valid_tm(t);
 141}
 142
 143
 144static int fm3130_set_time(struct device *dev, struct rtc_time *t)
 145{
 146        struct fm3130 *fm3130 = dev_get_drvdata(dev);
 147        int             tmp, i;
 148        u8              *buf = fm3130->regs;
 149
 150        dev_dbg(dev, "%s secs=%d, mins=%d, "
 151                "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
 152                "write", t->tm_sec, t->tm_min,
 153                t->tm_hour, t->tm_mday,
 154                t->tm_mon, t->tm_year, t->tm_wday);
 155
 156        /* first register addr */
 157        buf[FM3130_RTC_SECONDS] = bin2bcd(t->tm_sec);
 158        buf[FM3130_RTC_MINUTES] = bin2bcd(t->tm_min);
 159        buf[FM3130_RTC_HOURS] = bin2bcd(t->tm_hour);
 160        buf[FM3130_RTC_DAY] = bin2bcd(t->tm_wday + 1);
 161        buf[FM3130_RTC_DATE] = bin2bcd(t->tm_mday);
 162        buf[FM3130_RTC_MONTHS] = bin2bcd(t->tm_mon + 1);
 163
 164        /* assume 20YY not 19YY */
 165        tmp = t->tm_year - 100;
 166        buf[FM3130_RTC_YEARS] = bin2bcd(tmp);
 167
 168        dev_dbg(dev, "%s: %15ph\n", "write", buf);
 169
 170        fm3130_rtc_mode(dev, FM3130_MODE_WRITE);
 171
 172        /* Writing time registers, we don't support multibyte transfers */
 173        for (i = 0; i < FM3130_CLOCK_REGS; i++) {
 174                i2c_smbus_write_byte_data(fm3130->client,
 175                                        FM3130_RTC_SECONDS + i,
 176                                        fm3130->regs[FM3130_RTC_SECONDS + i]);
 177        }
 178
 179        fm3130_rtc_mode(dev, FM3130_MODE_NORMAL);
 180
 181        /* We assume here that data are valid once written */
 182        if (!fm3130->data_valid)
 183                fm3130->data_valid = 1;
 184        return 0;
 185}
 186
 187static int fm3130_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 188{
 189        struct fm3130 *fm3130 = dev_get_drvdata(dev);
 190        int tmp;
 191        struct rtc_time *tm = &alrm->time;
 192
 193        if (!fm3130->alarm_valid) {
 194                /*
 195                 * We have invalid alarm in RTC, probably due to battery faults
 196                 * or other problems. Return EIO for now, it will allow us to
 197                 * set alarm value later instead of error during probing which
 198                 * disables device
 199                 */
 200                return -EIO;
 201        }
 202
 203        /* read the RTC alarm registers all at once */
 204        tmp = i2c_transfer(to_i2c_adapter(fm3130->client->dev.parent),
 205                        &fm3130->msg[2], 2);
 206        if (tmp != 2) {
 207                dev_err(dev, "%s error %d\n", "read", tmp);
 208                return -EIO;
 209        }
 210        dev_dbg(dev, "alarm read %02x %02x %02x %02x %02x\n",
 211                        fm3130->regs[FM3130_ALARM_SECONDS],
 212                        fm3130->regs[FM3130_ALARM_MINUTES],
 213                        fm3130->regs[FM3130_ALARM_HOURS],
 214                        fm3130->regs[FM3130_ALARM_DATE],
 215                        fm3130->regs[FM3130_ALARM_MONTHS]);
 216
 217        tm->tm_sec      = bcd2bin(fm3130->regs[FM3130_ALARM_SECONDS] & 0x7F);
 218        tm->tm_min      = bcd2bin(fm3130->regs[FM3130_ALARM_MINUTES] & 0x7F);
 219        tm->tm_hour     = bcd2bin(fm3130->regs[FM3130_ALARM_HOURS] & 0x3F);
 220        tm->tm_mday     = bcd2bin(fm3130->regs[FM3130_ALARM_DATE] & 0x3F);
 221        tm->tm_mon      = bcd2bin(fm3130->regs[FM3130_ALARM_MONTHS] & 0x1F);
 222
 223        if (tm->tm_mon > 0)
 224                tm->tm_mon -= 1; /* RTC is 1-12, tm_mon is 0-11 */
 225
 226        dev_dbg(dev, "%s secs=%d, mins=%d, "
 227                "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
 228                "read alarm", tm->tm_sec, tm->tm_min,
 229                tm->tm_hour, tm->tm_mday,
 230                tm->tm_mon, tm->tm_year, tm->tm_wday);
 231
 232        /* check if alarm enabled */
 233        fm3130->regs[FM3130_RTC_CONTROL] =
 234                i2c_smbus_read_byte_data(fm3130->client, FM3130_RTC_CONTROL);
 235
 236        if ((fm3130->regs[FM3130_RTC_CONTROL] & FM3130_RTC_CONTROL_BIT_AEN) &&
 237                (~fm3130->regs[FM3130_RTC_CONTROL] &
 238                        FM3130_RTC_CONTROL_BIT_CAL)) {
 239                alrm->enabled = 1;
 240        }
 241
 242        return 0;
 243}
 244
 245static int fm3130_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 246{
 247        struct fm3130 *fm3130 = dev_get_drvdata(dev);
 248        struct rtc_time *tm = &alrm->time;
 249        int i;
 250
 251        dev_dbg(dev, "%s secs=%d, mins=%d, "
 252                "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
 253                "write alarm", tm->tm_sec, tm->tm_min,
 254                tm->tm_hour, tm->tm_mday,
 255                tm->tm_mon, tm->tm_year, tm->tm_wday);
 256
 257        fm3130->regs[FM3130_ALARM_SECONDS] =
 258                (tm->tm_sec != -1) ? bin2bcd(tm->tm_sec) : 0x80;
 259
 260        fm3130->regs[FM3130_ALARM_MINUTES] =
 261                (tm->tm_min != -1) ? bin2bcd(tm->tm_min) : 0x80;
 262
 263        fm3130->regs[FM3130_ALARM_HOURS] =
 264                (tm->tm_hour != -1) ? bin2bcd(tm->tm_hour) : 0x80;
 265
 266        fm3130->regs[FM3130_ALARM_DATE] =
 267                (tm->tm_mday != -1) ? bin2bcd(tm->tm_mday) : 0x80;
 268
 269        fm3130->regs[FM3130_ALARM_MONTHS] =
 270                (tm->tm_mon != -1) ? bin2bcd(tm->tm_mon + 1) : 0x80;
 271
 272        dev_dbg(dev, "alarm write %02x %02x %02x %02x %02x\n",
 273                        fm3130->regs[FM3130_ALARM_SECONDS],
 274                        fm3130->regs[FM3130_ALARM_MINUTES],
 275                        fm3130->regs[FM3130_ALARM_HOURS],
 276                        fm3130->regs[FM3130_ALARM_DATE],
 277                        fm3130->regs[FM3130_ALARM_MONTHS]);
 278        /* Writing time registers, we don't support multibyte transfers */
 279        for (i = 0; i < FM3130_ALARM_REGS; i++) {
 280                i2c_smbus_write_byte_data(fm3130->client,
 281                                        FM3130_ALARM_SECONDS + i,
 282                                        fm3130->regs[FM3130_ALARM_SECONDS + i]);
 283        }
 284        fm3130->regs[FM3130_RTC_CONTROL] =
 285                i2c_smbus_read_byte_data(fm3130->client, FM3130_RTC_CONTROL);
 286
 287        /* enable or disable alarm */
 288        if (alrm->enabled) {
 289                i2c_smbus_write_byte_data(fm3130->client, FM3130_RTC_CONTROL,
 290                        (fm3130->regs[FM3130_RTC_CONTROL] &
 291                                ~(FM3130_RTC_CONTROL_BIT_CAL)) |
 292                                        FM3130_RTC_CONTROL_BIT_AEN);
 293        } else {
 294                i2c_smbus_write_byte_data(fm3130->client, FM3130_RTC_CONTROL,
 295                        fm3130->regs[FM3130_RTC_CONTROL] &
 296                                ~(FM3130_RTC_CONTROL_BIT_CAL) &
 297                                        ~(FM3130_RTC_CONTROL_BIT_AEN));
 298        }
 299
 300        /* We assume here that data is valid once written */
 301        if (!fm3130->alarm_valid)
 302                fm3130->alarm_valid = 1;
 303
 304        return 0;
 305}
 306
 307static int fm3130_alarm_irq_enable(struct device *dev, unsigned int enabled)
 308{
 309        struct fm3130 *fm3130 = dev_get_drvdata(dev);
 310        int ret = 0;
 311
 312        fm3130->regs[FM3130_RTC_CONTROL] =
 313                i2c_smbus_read_byte_data(fm3130->client, FM3130_RTC_CONTROL);
 314
 315        dev_dbg(dev, "alarm_irq_enable: enable=%d, FM3130_RTC_CONTROL=%02x\n",
 316                enabled, fm3130->regs[FM3130_RTC_CONTROL]);
 317
 318        switch (enabled) {
 319        case 0:         /* alarm off */
 320                ret = i2c_smbus_write_byte_data(fm3130->client,
 321                        FM3130_RTC_CONTROL, fm3130->regs[FM3130_RTC_CONTROL] &
 322                                ~(FM3130_RTC_CONTROL_BIT_CAL) &
 323                                        ~(FM3130_RTC_CONTROL_BIT_AEN));
 324                break;
 325        case 1:         /* alarm on */
 326                ret = i2c_smbus_write_byte_data(fm3130->client,
 327                        FM3130_RTC_CONTROL, (fm3130->regs[FM3130_RTC_CONTROL] &
 328                                ~(FM3130_RTC_CONTROL_BIT_CAL)) |
 329                                        FM3130_RTC_CONTROL_BIT_AEN);
 330                break;
 331        default:
 332                ret = -EINVAL;
 333                break;
 334        }
 335
 336        return ret;
 337}
 338
 339static const struct rtc_class_ops fm3130_rtc_ops = {
 340        .read_time      = fm3130_get_time,
 341        .set_time       = fm3130_set_time,
 342        .read_alarm     = fm3130_read_alarm,
 343        .set_alarm      = fm3130_set_alarm,
 344        .alarm_irq_enable = fm3130_alarm_irq_enable,
 345};
 346
 347static struct i2c_driver fm3130_driver;
 348
 349static int fm3130_probe(struct i2c_client *client,
 350                        const struct i2c_device_id *id)
 351{
 352        struct fm3130           *fm3130;
 353        int                     err = -ENODEV;
 354        int                     tmp;
 355        struct i2c_adapter      *adapter = to_i2c_adapter(client->dev.parent);
 356
 357        if (!i2c_check_functionality(adapter,
 358                        I2C_FUNC_I2C | I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
 359                return -EIO;
 360
 361        fm3130 = devm_kzalloc(&client->dev, sizeof(struct fm3130), GFP_KERNEL);
 362
 363        if (!fm3130)
 364                return -ENOMEM;
 365
 366        fm3130->client = client;
 367        i2c_set_clientdata(client, fm3130);
 368        fm3130->reg_addr_time = FM3130_RTC_SECONDS;
 369        fm3130->reg_addr_alarm = FM3130_ALARM_SECONDS;
 370
 371        /* Messages to read time */
 372        fm3130->msg[0].addr = client->addr;
 373        fm3130->msg[0].flags = 0;
 374        fm3130->msg[0].len = 1;
 375        fm3130->msg[0].buf = &fm3130->reg_addr_time;
 376
 377        fm3130->msg[1].addr = client->addr;
 378        fm3130->msg[1].flags = I2C_M_RD;
 379        fm3130->msg[1].len = FM3130_CLOCK_REGS;
 380        fm3130->msg[1].buf = &fm3130->regs[FM3130_RTC_SECONDS];
 381
 382        /* Messages to read alarm */
 383        fm3130->msg[2].addr = client->addr;
 384        fm3130->msg[2].flags = 0;
 385        fm3130->msg[2].len = 1;
 386        fm3130->msg[2].buf = &fm3130->reg_addr_alarm;
 387
 388        fm3130->msg[3].addr = client->addr;
 389        fm3130->msg[3].flags = I2C_M_RD;
 390        fm3130->msg[3].len = FM3130_ALARM_REGS;
 391        fm3130->msg[3].buf = &fm3130->regs[FM3130_ALARM_SECONDS];
 392
 393        fm3130->alarm_valid = 0;
 394        fm3130->data_valid = 0;
 395
 396        tmp = i2c_transfer(adapter, fm3130->msg, 4);
 397        if (tmp != 4) {
 398                dev_dbg(&client->dev, "read error %d\n", tmp);
 399                err = -EIO;
 400                goto exit_free;
 401        }
 402
 403        fm3130->regs[FM3130_RTC_CONTROL] =
 404                i2c_smbus_read_byte_data(client, FM3130_RTC_CONTROL);
 405        fm3130->regs[FM3130_CAL_CONTROL] =
 406                i2c_smbus_read_byte_data(client, FM3130_CAL_CONTROL);
 407
 408        /* Disabling calibration mode */
 409        if (fm3130->regs[FM3130_RTC_CONTROL] & FM3130_RTC_CONTROL_BIT_CAL) {
 410                i2c_smbus_write_byte_data(client, FM3130_RTC_CONTROL,
 411                        fm3130->regs[FM3130_RTC_CONTROL] &
 412                                ~(FM3130_RTC_CONTROL_BIT_CAL));
 413                dev_warn(&client->dev, "Disabling calibration mode!\n");
 414        }
 415
 416        /* Disabling read and write modes */
 417        if (fm3130->regs[FM3130_RTC_CONTROL] & FM3130_RTC_CONTROL_BIT_WRITE ||
 418            fm3130->regs[FM3130_RTC_CONTROL] & FM3130_RTC_CONTROL_BIT_READ) {
 419                i2c_smbus_write_byte_data(client, FM3130_RTC_CONTROL,
 420                        fm3130->regs[FM3130_RTC_CONTROL] &
 421                                ~(FM3130_RTC_CONTROL_BIT_READ |
 422                                        FM3130_RTC_CONTROL_BIT_WRITE));
 423                dev_warn(&client->dev, "Disabling READ or WRITE mode!\n");
 424        }
 425
 426        /* oscillator off?  turn it on, so clock can tick. */
 427        if (fm3130->regs[FM3130_CAL_CONTROL] & FM3130_CAL_CONTROL_BIT_nOSCEN)
 428                i2c_smbus_write_byte_data(client, FM3130_CAL_CONTROL,
 429                        fm3130->regs[FM3130_CAL_CONTROL] &
 430                                ~(FM3130_CAL_CONTROL_BIT_nOSCEN));
 431
 432        /* low battery?  clear flag, and warn */
 433        if (fm3130->regs[FM3130_RTC_CONTROL] & FM3130_RTC_CONTROL_BIT_LB) {
 434                i2c_smbus_write_byte_data(client, FM3130_RTC_CONTROL,
 435                        fm3130->regs[FM3130_RTC_CONTROL] &
 436                                ~(FM3130_RTC_CONTROL_BIT_LB));
 437                dev_warn(&client->dev, "Low battery!\n");
 438        }
 439
 440        /* check if Power On Reset bit is set */
 441        if (fm3130->regs[FM3130_RTC_CONTROL] & FM3130_RTC_CONTROL_BIT_POR) {
 442                i2c_smbus_write_byte_data(client, FM3130_RTC_CONTROL,
 443                        fm3130->regs[FM3130_RTC_CONTROL] &
 444                                ~FM3130_RTC_CONTROL_BIT_POR);
 445                dev_dbg(&client->dev, "POR bit is set\n");
 446        }
 447        /* ACS is controlled by alarm */
 448        i2c_smbus_write_byte_data(client, FM3130_ALARM_WP_CONTROL, 0x80);
 449
 450        /* alarm registers sanity check */
 451        tmp = bcd2bin(fm3130->regs[FM3130_RTC_SECONDS] & 0x7f);
 452        if (tmp > 59)
 453                goto bad_alarm;
 454
 455        tmp = bcd2bin(fm3130->regs[FM3130_RTC_MINUTES] & 0x7f);
 456        if (tmp > 59)
 457                goto bad_alarm;
 458
 459        tmp = bcd2bin(fm3130->regs[FM3130_RTC_HOURS] & 0x3f);
 460        if (tmp > 23)
 461                goto bad_alarm;
 462
 463        tmp = bcd2bin(fm3130->regs[FM3130_RTC_DATE] & 0x3f);
 464        if (tmp == 0 || tmp > 31)
 465                goto bad_alarm;
 466
 467        tmp = bcd2bin(fm3130->regs[FM3130_RTC_MONTHS] & 0x1f);
 468        if (tmp == 0 || tmp > 12)
 469                goto bad_alarm;
 470
 471        fm3130->alarm_valid = 1;
 472
 473bad_alarm:
 474
 475        /* clock registers sanity chek */
 476        tmp = bcd2bin(fm3130->regs[FM3130_RTC_SECONDS] & 0x7f);
 477        if (tmp > 59)
 478                goto bad_clock;
 479
 480        tmp = bcd2bin(fm3130->regs[FM3130_RTC_MINUTES] & 0x7f);
 481        if (tmp > 59)
 482                goto bad_clock;
 483
 484        tmp = bcd2bin(fm3130->regs[FM3130_RTC_HOURS] & 0x3f);
 485        if (tmp > 23)
 486                goto bad_clock;
 487
 488        tmp = bcd2bin(fm3130->regs[FM3130_RTC_DAY] & 0x7);
 489        if (tmp == 0 || tmp > 7)
 490                goto bad_clock;
 491
 492        tmp = bcd2bin(fm3130->regs[FM3130_RTC_DATE] & 0x3f);
 493        if (tmp == 0 || tmp > 31)
 494                goto bad_clock;
 495
 496        tmp = bcd2bin(fm3130->regs[FM3130_RTC_MONTHS] & 0x1f);
 497        if (tmp == 0 || tmp > 12)
 498                goto bad_clock;
 499
 500        fm3130->data_valid = 1;
 501
 502bad_clock:
 503
 504        if (!fm3130->data_valid || !fm3130->alarm_valid)
 505                dev_dbg(&client->dev, "%s: %15ph\n", "bogus registers",
 506                        fm3130->regs);
 507
 508        /* We won't bail out here because we just got invalid data.
 509           Time setting from u-boot doesn't work anyway */
 510        fm3130->rtc = devm_rtc_device_register(&client->dev, client->name,
 511                                &fm3130_rtc_ops, THIS_MODULE);
 512        if (IS_ERR(fm3130->rtc)) {
 513                err = PTR_ERR(fm3130->rtc);
 514                dev_err(&client->dev,
 515                        "unable to register the class device\n");
 516                goto exit_free;
 517        }
 518        return 0;
 519exit_free:
 520        return err;
 521}
 522
 523static struct i2c_driver fm3130_driver = {
 524        .driver = {
 525                .name   = "rtc-fm3130",
 526                .owner  = THIS_MODULE,
 527        },
 528        .probe          = fm3130_probe,
 529        .id_table       = fm3130_id,
 530};
 531
 532module_i2c_driver(fm3130_driver);
 533
 534MODULE_DESCRIPTION("RTC driver for FM3130");
 535MODULE_AUTHOR("Sergey Lapin <slapin@ossfans.org>");
 536MODULE_LICENSE("GPL");
 537
 538