drivers/rtc/rtc-x1205.c

   1 /*
   2  * An i2c driver for the Xicor/Intersil X1205 RTC
   3  * Copyright 2004 Karen Spearel
   4  * Copyright 2005 Alessandro Zummo
   5  *
   6  * please send all reports to:
   7  *      Karen Spearel <kas111 at gmail dot com>
   8  *      Alessandro Zummo <a.zummo@towertech.it>
   9  *
  10  * based on a lot of other RTC drivers.
  11  *
  12  * Information and datasheet:
  13  * http://www.intersil.com/cda/deviceinfo/0,1477,X1205,00.html
  14  *
  15  * This program is free software; you can redistribute it and/or modify
  16  * it under the terms of the GNU General Public License version 2 as
  17  * published by the Free Software Foundation.
  18  */
  19
  20 #include <linux/i2c.h>
  21 #include <linux/bcd.h>
  22 #include <linux/rtc.h>
  23 #include <linux/delay.h>
  24
  25 #define DRV_VERSION "1.0.8"
  26
  27 /* offsets into CCR area */
  28
  29 #define CCR_SEC                 0
  30 #define CCR_MIN                 1
  31 #define CCR_HOUR                2
  32 #define CCR_MDAY                3
  33 #define CCR_MONTH               4
  34 #define CCR_YEAR                5
  35 #define CCR_WDAY                6
  36 #define CCR_Y2K                 7
  37
  38 #define X1205_REG_SR            0x3F    /* status register */
  39 #define X1205_REG_Y2K           0x37
  40 #define X1205_REG_DW            0x36
  41 #define X1205_REG_YR            0x35
  42 #define X1205_REG_MO            0x34
  43 #define X1205_REG_DT            0x33
  44 #define X1205_REG_HR            0x32
  45 #define X1205_REG_MN            0x31
  46 #define X1205_REG_SC            0x30
  47 #define X1205_REG_DTR           0x13
  48 #define X1205_REG_ATR           0x12
  49 #define X1205_REG_INT           0x11
  50 #define X1205_REG_0             0x10
  51 #define X1205_REG_Y2K1          0x0F
  52 #define X1205_REG_DWA1          0x0E
  53 #define X1205_REG_YRA1          0x0D
  54 #define X1205_REG_MOA1          0x0C
  55 #define X1205_REG_DTA1          0x0B
  56 #define X1205_REG_HRA1          0x0A
  57 #define X1205_REG_MNA1          0x09
  58 #define X1205_REG_SCA1          0x08
  59 #define X1205_REG_Y2K0          0x07
  60 #define X1205_REG_DWA0          0x06
  61 #define X1205_REG_YRA0          0x05
  62 #define X1205_REG_MOA0          0x04
  63 #define X1205_REG_DTA0          0x03
  64 #define X1205_REG_HRA0          0x02
  65 #define X1205_REG_MNA0          0x01
  66 #define X1205_REG_SCA0          0x00
  67
  68 #define X1205_CCR_BASE          0x30    /* Base address of CCR */
  69 #define X1205_ALM0_BASE         0x00    /* Base address of ALARM0 */
  70
  71 #define X1205_SR_RTCF           0x01    /* Clock failure */
  72 #define X1205_SR_WEL            0x02    /* Write Enable Latch */
  73 #define X1205_SR_RWEL           0x04    /* Register Write Enable */
  74 #define X1205_SR_AL0            0x20    /* Alarm 0 match */
  75
  76 #define X1205_DTR_DTR0          0x01
  77 #define X1205_DTR_DTR1          0x02
  78 #define X1205_DTR_DTR2          0x04
  79
  80 #define X1205_HR_MIL            0x80    /* Set in ccr.hour for 24 hr mode */
  81
  82 #define X1205_INT_AL0E          0x20    /* Alarm 0 enable */
  83
  84 static struct i2c_driver x1205_driver;
  85
  86 /*
  87  * In the routines that deal directly with the x1205 hardware, we use
  88  * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch
  89  * Epoch is initialized as 2000. Time is set to UTC.
  90  */
  91 static int x1205_get_datetime(struct i2c_client *client, struct rtc_time *tm,
  92                                 unsigned char reg_base)
  93 {
  94         unsigned char dt_addr[2] = { 0, reg_base };
  95         unsigned char buf[8];
  96         int i;
  97
  98         struct i2c_msg msgs[] = {
  99                 { client->addr, 0, 2, dt_addr },        /* setup read ptr */
 100                 { client->addr, I2C_M_RD, 8, buf },     /* read date */
 101         };
 102
 103         /* read date registers */
 104         if (i2c_transfer(client->adapter, &msgs[0], 2) != 2) {
 105                 dev_err(&client->dev, "%s: read error\n", __func__);
 106                 return -EIO;
 107         }
 108
 109         dev_dbg(&client->dev,
 110                 "%s: raw read data - sec=%02x, min=%02x, hr=%02x, "
 111                 "mday=%02x, mon=%02x, year=%02x, wday=%02x, y2k=%02x\n",
 112                 __func__,
 113                 buf[0], buf[1], buf[2], buf[3],
 114                 buf[4], buf[5], buf[6], buf[7]);
 115
 116         /* Mask out the enable bits if these are alarm registers */
 117         if (reg_base < X1205_CCR_BASE)
 118                 for (i = 0; i <= 4; i++)
 119                         buf[i] &= 0x7F;
 120
 121         tm->tm_sec = BCD2BIN(buf[CCR_SEC]);
 122         tm->tm_min = BCD2BIN(buf[CCR_MIN]);
 123         tm->tm_hour = BCD2BIN(buf[CCR_HOUR] & 0x3F); /* hr is 0-23 */
 124         tm->tm_mday = BCD2BIN(buf[CCR_MDAY]);
 125         tm->tm_mon = BCD2BIN(buf[CCR_MONTH]) - 1; /* mon is 0-11 */
 126         tm->tm_year = BCD2BIN(buf[CCR_YEAR])
 127                         + (BCD2BIN(buf[CCR_Y2K]) * 100) - 1900;
 128         tm->tm_wday = buf[CCR_WDAY];
 129
 130         dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
 131                 "mday=%d, mon=%d, year=%d, wday=%d\n",
 132                 __func__,
 133                 tm->tm_sec, tm->tm_min, tm->tm_hour,
 134                 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
 135
 136         return 0;
 137 }
 138
 139 static int x1205_get_status(struct i2c_client *client, unsigned char *sr)
 140 {
 141         static unsigned char sr_addr[2] = { 0, X1205_REG_SR };
 142
 143         struct i2c_msg msgs[] = {
 144                 { client->addr, 0, 2, sr_addr },        /* setup read ptr */
 145                 { client->addr, I2C_M_RD, 1, sr },      /* read status */
 146         };
 147
 148         /* read status register */
 149         if (i2c_transfer(client->adapter, &msgs[0], 2) != 2) {
 150                 dev_err(&client->dev, "%s: read error\n", __func__);
 151                 return -EIO;
 152         }
 153
 154         return 0;
 155 }
 156
 157 static int x1205_set_datetime(struct i2c_client *client, struct rtc_time *tm,
 158                         int datetoo, u8 reg_base, unsigned char alm_enable)
 159 {
 160         int i, xfer, nbytes;
 161         unsigned char buf[8];
 162         unsigned char rdata[10] = { 0, reg_base };
 163
 164         static const unsigned char wel[3] = { 0, X1205_REG_SR,
 165                                                 X1205_SR_WEL };
 166
 167         static const unsigned char rwel[3] = { 0, X1205_REG_SR,
 168                                                 X1205_SR_WEL | X1205_SR_RWEL };
 169
 170         static const unsigned char diswe[3] = { 0, X1205_REG_SR, 0 };
 171
 172         dev_dbg(&client->dev,
 173                 "%s: secs=%d, mins=%d, hours=%d\n",
 174                 __func__,
 175                 tm->tm_sec, tm->tm_min, tm->tm_hour);
 176
 177         buf[CCR_SEC] = BIN2BCD(tm->tm_sec);
 178         buf[CCR_MIN] = BIN2BCD(tm->tm_min);
 179
 180         /* set hour and 24hr bit */
 181         buf[CCR_HOUR] = BIN2BCD(tm->tm_hour) | X1205_HR_MIL;
 182
 183         /* should we also set the date? */
 184         if (datetoo) {
 185                 dev_dbg(&client->dev,
 186                         "%s: mday=%d, mon=%d, year=%d, wday=%d\n",
 187                         __func__,
 188                         tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
 189
 190                 buf[CCR_MDAY] = BIN2BCD(tm->tm_mday);
 191
 192                 /* month, 1 - 12 */
 193                 buf[CCR_MONTH] = BIN2BCD(tm->tm_mon + 1);
 194
 195                 /* year, since the rtc epoch*/
 196                 buf[CCR_YEAR] = BIN2BCD(tm->tm_year % 100);
 197                 buf[CCR_WDAY] = tm->tm_wday & 0x07;
 198                 buf[CCR_Y2K] = BIN2BCD(tm->tm_year / 100);
 199         }
 200
 201         /* If writing alarm registers, set compare bits on registers 0-4 */
 202         if (reg_base < X1205_CCR_BASE)
 203                 for (i = 0; i <= 4; i++)
 204                         buf[i] |= 0x80;
 205
 206         /* this sequence is required to unlock the chip */
 207         if ((xfer = i2c_master_send(client, wel, 3)) != 3) {
 208                 dev_err(&client->dev, "%s: wel - %d\n", __func__, xfer);
 209                 return -EIO;
 210         }
 211
 212         if ((xfer = i2c_master_send(client, rwel, 3)) != 3) {
 213                 dev_err(&client->dev, "%s: rwel - %d\n", __func__, xfer);
 214                 return -EIO;
 215         }
 216
 217
 218         /* write register's data */
 219         if (datetoo)
 220                 nbytes = 8;
 221         else
 222                 nbytes = 3;
 223         for (i = 0; i < nbytes; i++)
 224                 rdata[2+i] = buf[i];
 225
 226         xfer = i2c_master_send(client, rdata, nbytes+2);
 227         if (xfer != nbytes+2) {
 228                 dev_err(&client->dev,
 229                         "%s: result=%d addr=%02x, data=%02x\n",
 230                         __func__,
 231                          xfer, rdata[1], rdata[2]);
 232                 return -EIO;
 233         }
 234
 235         /* If we wrote to the nonvolatile region, wait 10msec for write cycle*/
 236         if (reg_base < X1205_CCR_BASE) {
 237                 unsigned char al0e[3] = { 0, X1205_REG_INT, 0 };
 238
 239                 msleep(10);
 240
 241                 /* ...and set or clear the AL0E bit in the INT register */
 242
 243                 /* Need to set RWEL again as the write has cleared it */
 244                 xfer = i2c_master_send(client, rwel, 3);
 245                 if (xfer != 3) {
 246                         dev_err(&client->dev,
 247                                 "%s: aloe rwel - %d\n",
 248                                 __func__,
 249                                 xfer);
 250                         return -EIO;
 251                 }
 252
 253                 if (alm_enable)
 254                         al0e[2] = X1205_INT_AL0E;
 255
 256                 xfer = i2c_master_send(client, al0e, 3);
 257                 if (xfer != 3) {
 258                         dev_err(&client->dev,
 259                                 "%s: al0e - %d\n",
 260                                 __func__,
 261                                 xfer);
 262                         return -EIO;
 263                 }
 264
 265                 /* and wait 10msec again for this write to complete */
 266                 msleep(10);
 267         }
 268
 269         /* disable further writes */
 270         if ((xfer = i2c_master_send(client, diswe, 3)) != 3) {
 271                 dev_err(&client->dev, "%s: diswe - %d\n", __func__, xfer);
 272                 return -EIO;
 273         }
 274
 275         return 0;
 276 }
 277
 278 static int x1205_fix_osc(struct i2c_client *client)
 279 {
 280         int err;
 281         struct rtc_time tm;
 282
 283         tm.tm_hour = tm.tm_min = tm.tm_sec = 0;
 284
 285         err = x1205_set_datetime(client, &tm, 0, X1205_CCR_BASE, 0);
 286         if (err < 0)
 287                 dev_err(&client->dev, "unable to restart the oscillator\n");
 288
 289         return err;
 290 }
 291
 292 static int x1205_get_dtrim(struct i2c_client *client, int *trim)
 293 {
 294         unsigned char dtr;
 295         static unsigned char dtr_addr[2] = { 0, X1205_REG_DTR };
 296
 297         struct i2c_msg msgs[] = {
 298                 { client->addr, 0, 2, dtr_addr },       /* setup read ptr */
 299                 { client->addr, I2C_M_RD, 1, &dtr },    /* read dtr */
 300         };
 301
 302         /* read dtr register */
 303         if (i2c_transfer(client->adapter, &msgs[0], 2) != 2) {
 304                 dev_err(&client->dev, "%s: read error\n", __func__);
 305                 return -EIO;
 306         }
 307
 308         dev_dbg(&client->dev, "%s: raw dtr=%x\n", __func__, dtr);
 309
 310         *trim = 0;
 311
 312         if (dtr & X1205_DTR_DTR0)
 313                 *trim += 20;
 314
 315         if (dtr & X1205_DTR_DTR1)
 316                 *trim += 10;
 317
 318         if (dtr & X1205_DTR_DTR2)
 319                 *trim = -*trim;
 320
 321         return 0;
 322 }
 323
 324 static int x1205_get_atrim(struct i2c_client *client, int *trim)
 325 {
 326         s8 atr;
 327         static unsigned char atr_addr[2] = { 0, X1205_REG_ATR };
 328
 329         struct i2c_msg msgs[] = {
 330                 { client->addr, 0, 2, atr_addr },       /* setup read ptr */
 331                 { client->addr, I2C_M_RD, 1, &atr },    /* read atr */
 332         };
 333
 334         /* read atr register */
 335         if (i2c_transfer(client->adapter, &msgs[0], 2) != 2) {
 336                 dev_err(&client->dev, "%s: read error\n", __func__);
 337                 return -EIO;
 338         }
 339
 340         dev_dbg(&client->dev, "%s: raw atr=%x\n", __func__, atr);
 341
 342         /* atr is a two's complement value on 6 bits,
 343          * perform sign extension. The formula is
 344          * Catr = (atr * 0.25pF) + 11.00pF.
 345          */
 346         if (atr & 0x20)
 347                 atr |= 0xC0;
 348
 349         dev_dbg(&client->dev, "%s: raw atr=%x (%d)\n", __func__, atr, atr);
 350
 351         *trim = (atr * 250) + 11000;
 352
 353         dev_dbg(&client->dev, "%s: real=%d\n", __func__, *trim);
 354
 355         return 0;
 356 }
 357
 358 struct x1205_limit
 359 {
 360         unsigned char reg, mask, min, max;
 361 };
 362
 363 static int x1205_validate_client(struct i2c_client *client)
 364 {
 365         int i, xfer;
 366
 367         /* Probe array. We will read the register at the specified
 368          * address and check if the given bits are zero.
 369          */
 370         static const unsigned char probe_zero_pattern[] = {
 371                 /* register, mask */
 372                 X1205_REG_SR,   0x18,
 373                 X1205_REG_DTR,  0xF8,
 374                 X1205_REG_ATR,  0xC0,
 375                 X1205_REG_INT,  0x18,
 376                 X1205_REG_0,    0xFF,
 377         };
 378
 379         static const struct x1205_limit probe_limits_pattern[] = {
 380                 /* register, mask, min, max */
 381                 { X1205_REG_Y2K,        0xFF,   19,     20      },
 382                 { X1205_REG_DW,         0xFF,   0,      6       },
 383                 { X1205_REG_YR,         0xFF,   0,      99      },
 384                 { X1205_REG_MO,         0xFF,   0,      12      },
 385                 { X1205_REG_DT,         0xFF,   0,      31      },
 386                 { X1205_REG_HR,         0x7F,   0,      23      },
 387                 { X1205_REG_MN,         0xFF,   0,      59      },
 388                 { X1205_REG_SC,         0xFF,   0,      59      },
 389                 { X1205_REG_Y2K1,       0xFF,   19,     20      },
 390                 { X1205_REG_Y2K0,       0xFF,   19,     20      },
 391         };
 392
 393         /* check that registers have bits a 0 where expected */
 394         for (i = 0; i < ARRAY_SIZE(probe_zero_pattern); i += 2) {
 395                 unsigned char buf;
 396
 397                 unsigned char addr[2] = { 0, probe_zero_pattern[i] };
 398
 399                 struct i2c_msg msgs[2] = {
 400                         { client->addr, 0, 2, addr },
 401                         { client->addr, I2C_M_RD, 1, &buf },
 402                 };
 403
 404                 if ((xfer = i2c_transfer(client->adapter, msgs, 2)) != 2) {
 405                         dev_err(&client->dev,
 406                                 "%s: could not read register %x\n",
 407                                 __func__, probe_zero_pattern[i]);
 408
 409                         return -EIO;
 410                 }
 411
 412                 if ((buf & probe_zero_pattern[i+1]) != 0) {
 413                         dev_err(&client->dev,
 414                                 "%s: register=%02x, zero pattern=%d, value=%x\n",
 415                                 __func__, probe_zero_pattern[i], i, buf);
 416
 417                         return -ENODEV;
 418                 }
 419         }
 420
 421         /* check limits (only registers with bcd values) */
 422         for (i = 0; i < ARRAY_SIZE(probe_limits_pattern); i++) {
 423                 unsigned char reg, value;
 424
 425                 unsigned char addr[2] = { 0, probe_limits_pattern[i].reg };
 426
 427                 struct i2c_msg msgs[2] = {
 428                         { client->addr, 0, 2, addr },
 429                         { client->addr, I2C_M_RD, 1, &reg },
 430                 };
 431
 432                 if ((xfer = i2c_transfer(client->adapter, msgs, 2)) != 2) {
 433                         dev_err(&client->dev,
 434                                 "%s: could not read register %x\n",
 435                                 __func__, probe_limits_pattern[i].reg);
 436
 437                         return -EIO;
 438                 }
 439
 440                 value = BCD2BIN(reg & probe_limits_pattern[i].mask);
 441
 442                 if (value > probe_limits_pattern[i].max ||
 443                         value < probe_limits_pattern[i].min) {
 444                         dev_dbg(&client->dev,
 445                                 "%s: register=%x, lim pattern=%d, value=%d\n",
 446                                 __func__, probe_limits_pattern[i].reg,
 447                                 i, value);
 448
 449                         return -ENODEV;
 450                 }
 451         }
 452
 453         return 0;
 454 }
 455
 456 static int x1205_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 457 {
 458         int err;
 459         unsigned char intreg, status;
 460         static unsigned char int_addr[2] = { 0, X1205_REG_INT };
 461         struct i2c_client *client = to_i2c_client(dev);
 462         struct i2c_msg msgs[] = {
 463                 { client->addr, 0, 2, int_addr },        /* setup read ptr */
 464                 { client->addr, I2C_M_RD, 1, &intreg },  /* read INT register */
 465         };
 466
 467         /* read interrupt register and status register */
 468         if (i2c_transfer(client->adapter, &msgs[0], 2) != 2) {
 469                 dev_err(&client->dev, "%s: read error\n", __func__);
 470                 return -EIO;
 471         }
 472         err = x1205_get_status(client, &status);
 473         if (err == 0) {
 474                 alrm->pending = (status & X1205_SR_AL0) ? 1 : 0;
 475                 alrm->enabled = (intreg & X1205_INT_AL0E) ? 1 : 0;
 476                 err = x1205_get_datetime(client, &alrm->time, X1205_ALM0_BASE);
 477         }
 478         return err;
 479 }
 480
 481 static int x1205_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 482 {
 483         return x1205_set_datetime(to_i2c_client(dev),
 484                 &alrm->time, 1, X1205_ALM0_BASE, alrm->enabled);
 485 }
 486
 487 static int x1205_rtc_read_time(struct device *dev, struct rtc_time *tm)
 488 {
 489         return x1205_get_datetime(to_i2c_client(dev),
 490                 tm, X1205_CCR_BASE);
 491 }
 492
 493 static int x1205_rtc_set_time(struct device *dev, struct rtc_time *tm)
 494 {
 495         return x1205_set_datetime(to_i2c_client(dev),
 496                 tm, 1, X1205_CCR_BASE, 0);
 497 }
 498
 499 static int x1205_rtc_proc(struct device *dev, struct seq_file *seq)
 500 {
 501         int err, dtrim, atrim;
 502
 503         if ((err = x1205_get_dtrim(to_i2c_client(dev), &dtrim)) == 0)
 504                 seq_printf(seq, "digital_trim\t: %d ppm\n", dtrim);
 505
 506         if ((err = x1205_get_atrim(to_i2c_client(dev), &atrim)) == 0)
 507                 seq_printf(seq, "analog_trim\t: %d.%02d pF\n",
 508                         atrim / 1000, atrim % 1000);
 509         return 0;
 510 }
 511
 512 static const struct rtc_class_ops x1205_rtc_ops = {
 513         .proc           = x1205_rtc_proc,
 514         .read_time      = x1205_rtc_read_time,
 515         .set_time       = x1205_rtc_set_time,
 516         .read_alarm     = x1205_rtc_read_alarm,
 517         .set_alarm      = x1205_rtc_set_alarm,
 518 };
 519
 520 static ssize_t x1205_sysfs_show_atrim(struct device *dev,
 521                                 struct device_attribute *attr, char *buf)
 522 {
 523         int err, atrim;
 524
 525         err = x1205_get_atrim(to_i2c_client(dev), &atrim);
 526         if (err)
 527                 return err;
 528
 529         return sprintf(buf, "%d.%02d pF\n", atrim / 1000, atrim % 1000);
 530 }
 531 static DEVICE_ATTR(atrim, S_IRUGO, x1205_sysfs_show_atrim, NULL);
 532
 533 static ssize_t x1205_sysfs_show_dtrim(struct device *dev,
 534                                 struct device_attribute *attr, char *buf)
 535 {
 536         int err, dtrim;
 537
 538         err = x1205_get_dtrim(to_i2c_client(dev), &dtrim);
 539         if (err)
 540                 return err;
 541
 542         return sprintf(buf, "%d ppm\n", dtrim);
 543 }
 544 static DEVICE_ATTR(dtrim, S_IRUGO, x1205_sysfs_show_dtrim, NULL);
 545
 546 static int x1205_sysfs_register(struct device *dev)
 547 {
 548         int err;
 549
 550         err = device_create_file(dev, &dev_attr_atrim);
 551         if (err)
 552                 return err;
 553
 554         err = device_create_file(dev, &dev_attr_dtrim);
 555         if (err)
 556                 device_remove_file(dev, &dev_attr_atrim);
 557
 558         return err;
 559 }
 560
 561 static void x1205_sysfs_unregister(struct device *dev)
 562 {
 563         device_remove_file(dev, &dev_attr_atrim);
 564         device_remove_file(dev, &dev_attr_dtrim);
 565 }
 566
 567
 568 static int x1205_probe(struct i2c_client *client,
 569                         const struct i2c_device_id *id)
 570 {
 571         int err = 0;
 572         unsigned char sr;
 573         struct rtc_device *rtc;
 574
 575         dev_dbg(&client->dev, "%s\n", __func__);
 576
 577         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
 578                 return -ENODEV;
 579
 580         if (x1205_validate_client(client) < 0)
 581                 return -ENODEV;
 582
 583         dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n");
 584
 585         rtc = rtc_device_register(x1205_driver.driver.name, &client->dev,
 586                                 &x1205_rtc_ops, THIS_MODULE);
 587
 588         if (IS_ERR(rtc))
 589                 return PTR_ERR(rtc);
 590
 591         i2c_set_clientdata(client, rtc);
 592
 593         /* Check for power failures and eventualy enable the osc */
 594         if ((err = x1205_get_status(client, &sr)) == 0) {
 595                 if (sr & X1205_SR_RTCF) {
 596                         dev_err(&client->dev,
 597                                 "power failure detected, "
 598                                 "please set the clock\n");
 599                         udelay(50);
 600                         x1205_fix_osc(client);
 601                 }
 602         }
 603         else
 604                 dev_err(&client->dev, "couldn't read status\n");
 605
 606         err = x1205_sysfs_register(&client->dev);
 607         if (err)
 608                 goto exit_devreg;
 609
 610         return 0;
 611
 612 exit_devreg:
 613         rtc_device_unregister(rtc);
 614
 615         return err;
 616 }
 617
 618 static int x1205_remove(struct i2c_client *client)
 619 {
 620         struct rtc_device *rtc = i2c_get_clientdata(client);
 621
 622         rtc_device_unregister(rtc);
 623         x1205_sysfs_unregister(&client->dev);
 624         return 0;
 625 }
 626
 627 static const struct i2c_device_id x1205_id[] = {
 628         { "x1205", 0 },
 629         { }
 630 };
 631 MODULE_DEVICE_TABLE(i2c, x1205_id);
 632
 633 static struct i2c_driver x1205_driver = {
 634         .driver         = {
 635                 .name   = "rtc-x1205",
 636         },
 637         .probe          = x1205_probe,
 638         .remove         = x1205_remove,
 639         .id_table       = x1205_id,
 640 };
 641
 642 static int __init x1205_init(void)
 643 {
 644         return i2c_add_driver(&x1205_driver);
 645 }
 646
 647 static void __exit x1205_exit(void)
 648 {
 649         i2c_del_driver(&x1205_driver);
 650 }
 651
 652 MODULE_AUTHOR(
 653         "Karen Spearel <kas111 at gmail dot com>, "
 654         "Alessandro Zummo <a.zummo@towertech.it>");
 655 MODULE_DESCRIPTION("Xicor/Intersil X1205 RTC driver");
 656 MODULE_LICENSE("GPL");
 657 MODULE_VERSION(DRV_VERSION);
 658
 659 module_init(x1205_init);
 660 module_exit(x1205_exit);