linux/drivers/rtc/rtc-rx8025.c
<<
>>
Prefs
   1/*
   2 * Driver for Epson's RTC module RX-8025 SA/NB
   3 *
   4 * Copyright (C) 2009 Wolfgang Grandegger <wg@grandegger.com>
   5 *
   6 * Copyright (C) 2005 by Digi International Inc.
   7 * All rights reserved.
   8 *
   9 * Modified by fengjh at rising.com.cn
  10 * <http://lists.lm-sensors.org/mailman/listinfo/lm-sensors>
  11 * 2006.11
  12 *
  13 * Code cleanup by Sergei Poselenov, <sposelenov@emcraft.com>
  14 * Converted to new style by Wolfgang Grandegger <wg@grandegger.com>
  15 * Alarm and periodic interrupt added by Dmitry Rakhchev <rda@emcraft.com>
  16 *
  17 * This program is free software; you can redistribute it and/or
  18 * modify it under the terms of the GNU General Public License
  19 * version 2 as published by the Free Software Foundation.
  20 */
  21#include <linux/kernel.h>
  22#include <linux/module.h>
  23#include <linux/slab.h>
  24#include <linux/init.h>
  25#include <linux/bcd.h>
  26#include <linux/i2c.h>
  27#include <linux/list.h>
  28#include <linux/rtc.h>
  29
  30/* Register definitions */
  31#define RX8025_REG_SEC          0x00
  32#define RX8025_REG_MIN          0x01
  33#define RX8025_REG_HOUR         0x02
  34#define RX8025_REG_WDAY         0x03
  35#define RX8025_REG_MDAY         0x04
  36#define RX8025_REG_MONTH        0x05
  37#define RX8025_REG_YEAR         0x06
  38#define RX8025_REG_DIGOFF       0x07
  39#define RX8025_REG_ALWMIN       0x08
  40#define RX8025_REG_ALWHOUR      0x09
  41#define RX8025_REG_ALWWDAY      0x0a
  42#define RX8025_REG_ALDMIN       0x0b
  43#define RX8025_REG_ALDHOUR      0x0c
  44/* 0x0d is reserved */
  45#define RX8025_REG_CTRL1        0x0e
  46#define RX8025_REG_CTRL2        0x0f
  47
  48#define RX8025_BIT_CTRL1_CT     (7 << 0)
  49/* 1 Hz periodic level irq */
  50#define RX8025_BIT_CTRL1_CT_1HZ 4
  51#define RX8025_BIT_CTRL1_TEST   (1 << 3)
  52#define RX8025_BIT_CTRL1_1224   (1 << 5)
  53#define RX8025_BIT_CTRL1_DALE   (1 << 6)
  54#define RX8025_BIT_CTRL1_WALE   (1 << 7)
  55
  56#define RX8025_BIT_CTRL2_DAFG   (1 << 0)
  57#define RX8025_BIT_CTRL2_WAFG   (1 << 1)
  58#define RX8025_BIT_CTRL2_CTFG   (1 << 2)
  59#define RX8025_BIT_CTRL2_PON    (1 << 4)
  60#define RX8025_BIT_CTRL2_XST    (1 << 5)
  61#define RX8025_BIT_CTRL2_VDET   (1 << 6)
  62
  63/* Clock precision adjustment */
  64#define RX8025_ADJ_RESOLUTION   3050 /* in ppb */
  65#define RX8025_ADJ_DATA_MAX     62
  66#define RX8025_ADJ_DATA_MIN     -62
  67
  68static const struct i2c_device_id rx8025_id[] = {
  69        { "rx8025", 0 },
  70        { }
  71};
  72MODULE_DEVICE_TABLE(i2c, rx8025_id);
  73
  74struct rx8025_data {
  75        struct i2c_client *client;
  76        struct rtc_device *rtc;
  77        struct work_struct work;
  78        u8 ctrl1;
  79        unsigned exiting:1;
  80};
  81
  82static int rx8025_read_reg(struct i2c_client *client, int number, u8 *value)
  83{
  84        int ret = i2c_smbus_read_byte_data(client, (number << 4) | 0x08);
  85
  86        if (ret < 0) {
  87                dev_err(&client->dev, "Unable to read register #%d\n", number);
  88                return ret;
  89        }
  90
  91        *value = ret;
  92        return 0;
  93}
  94
  95static int rx8025_read_regs(struct i2c_client *client,
  96                            int number, u8 length, u8 *values)
  97{
  98        int ret = i2c_smbus_read_i2c_block_data(client, (number << 4) | 0x08,
  99                                                length, values);
 100
 101        if (ret != length) {
 102                dev_err(&client->dev, "Unable to read registers #%d..#%d\n",
 103                        number, number + length - 1);
 104                return ret < 0 ? ret : -EIO;
 105        }
 106
 107        return 0;
 108}
 109
 110static int rx8025_write_reg(struct i2c_client *client, int number, u8 value)
 111{
 112        int ret = i2c_smbus_write_byte_data(client, number << 4, value);
 113
 114        if (ret)
 115                dev_err(&client->dev, "Unable to write register #%d\n",
 116                        number);
 117
 118        return ret;
 119}
 120
 121static int rx8025_write_regs(struct i2c_client *client,
 122                             int number, u8 length, u8 *values)
 123{
 124        int ret = i2c_smbus_write_i2c_block_data(client, (number << 4) | 0x08,
 125                                                 length, values);
 126
 127        if (ret)
 128                dev_err(&client->dev, "Unable to write registers #%d..#%d\n",
 129                        number, number + length - 1);
 130
 131        return ret;
 132}
 133
 134static irqreturn_t rx8025_irq(int irq, void *dev_id)
 135{
 136        struct i2c_client *client = dev_id;
 137        struct rx8025_data *rx8025 = i2c_get_clientdata(client);
 138
 139        disable_irq_nosync(irq);
 140        schedule_work(&rx8025->work);
 141        return IRQ_HANDLED;
 142}
 143
 144static void rx8025_work(struct work_struct *work)
 145{
 146        struct rx8025_data *rx8025 = container_of(work, struct rx8025_data,
 147                                                  work);
 148        struct i2c_client *client = rx8025->client;
 149        struct mutex *lock = &rx8025->rtc->ops_lock;
 150        u8 status;
 151
 152        mutex_lock(lock);
 153
 154        if (rx8025_read_reg(client, RX8025_REG_CTRL2, &status))
 155                goto out;
 156
 157        if (!(status & RX8025_BIT_CTRL2_XST))
 158                dev_warn(&client->dev, "Oscillation stop was detected,"
 159                         "you may have to readjust the clock\n");
 160
 161        if (status & RX8025_BIT_CTRL2_CTFG) {
 162                /* periodic */
 163                status &= ~RX8025_BIT_CTRL2_CTFG;
 164                local_irq_disable();
 165                rtc_update_irq(rx8025->rtc, 1, RTC_PF | RTC_IRQF);
 166                local_irq_enable();
 167        }
 168
 169        if (status & RX8025_BIT_CTRL2_DAFG) {
 170                /* alarm */
 171                status &= RX8025_BIT_CTRL2_DAFG;
 172                if (rx8025_write_reg(client, RX8025_REG_CTRL1,
 173                                     rx8025->ctrl1 & ~RX8025_BIT_CTRL1_DALE))
 174                        goto out;
 175                local_irq_disable();
 176                rtc_update_irq(rx8025->rtc, 1, RTC_AF | RTC_IRQF);
 177                local_irq_enable();
 178        }
 179
 180        /* acknowledge IRQ */
 181        rx8025_write_reg(client, RX8025_REG_CTRL2,
 182                         status | RX8025_BIT_CTRL2_XST);
 183
 184out:
 185        if (!rx8025->exiting)
 186                enable_irq(client->irq);
 187
 188        mutex_unlock(lock);
 189}
 190
 191static int rx8025_get_time(struct device *dev, struct rtc_time *dt)
 192{
 193        struct rx8025_data *rx8025 = dev_get_drvdata(dev);
 194        u8 date[7];
 195        int err;
 196
 197        err = rx8025_read_regs(rx8025->client, RX8025_REG_SEC, 7, date);
 198        if (err)
 199                return err;
 200
 201        dev_dbg(dev, "%s: read 0x%02x 0x%02x "
 202                "0x%02x 0x%02x 0x%02x 0x%02x 0x%02x\n", __func__,
 203                date[0], date[1], date[2], date[3], date[4],
 204                date[5], date[6]);
 205
 206        dt->tm_sec = bcd2bin(date[RX8025_REG_SEC] & 0x7f);
 207        dt->tm_min = bcd2bin(date[RX8025_REG_MIN] & 0x7f);
 208        if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
 209                dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x3f);
 210        else
 211                dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x1f) % 12
 212                        + (date[RX8025_REG_HOUR] & 0x20 ? 12 : 0);
 213
 214        dt->tm_mday = bcd2bin(date[RX8025_REG_MDAY] & 0x3f);
 215        dt->tm_mon = bcd2bin(date[RX8025_REG_MONTH] & 0x1f) - 1;
 216        dt->tm_year = bcd2bin(date[RX8025_REG_YEAR]);
 217
 218        if (dt->tm_year < 70)
 219                dt->tm_year += 100;
 220
 221        dev_dbg(dev, "%s: date %ds %dm %dh %dmd %dm %dy\n", __func__,
 222                dt->tm_sec, dt->tm_min, dt->tm_hour,
 223                dt->tm_mday, dt->tm_mon, dt->tm_year);
 224
 225        return rtc_valid_tm(dt);
 226}
 227
 228static int rx8025_set_time(struct device *dev, struct rtc_time *dt)
 229{
 230        struct rx8025_data *rx8025 = dev_get_drvdata(dev);
 231        u8 date[7];
 232
 233        /*
 234         * BUG: The HW assumes every year that is a multiple of 4 to be a leap
 235         * year.  Next time this is wrong is 2100, which will not be a leap
 236         * year.
 237         */
 238
 239        /*
 240         * Here the read-only bits are written as "0".  I'm not sure if that
 241         * is sound.
 242         */
 243        date[RX8025_REG_SEC] = bin2bcd(dt->tm_sec);
 244        date[RX8025_REG_MIN] = bin2bcd(dt->tm_min);
 245        if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
 246                date[RX8025_REG_HOUR] = bin2bcd(dt->tm_hour);
 247        else
 248                date[RX8025_REG_HOUR] = (dt->tm_hour >= 12 ? 0x20 : 0)
 249                        | bin2bcd((dt->tm_hour + 11) % 12 + 1);
 250
 251        date[RX8025_REG_WDAY] = bin2bcd(dt->tm_wday);
 252        date[RX8025_REG_MDAY] = bin2bcd(dt->tm_mday);
 253        date[RX8025_REG_MONTH] = bin2bcd(dt->tm_mon + 1);
 254        date[RX8025_REG_YEAR] = bin2bcd(dt->tm_year % 100);
 255
 256        dev_dbg(dev,
 257                "%s: write 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x\n",
 258                __func__,
 259                date[0], date[1], date[2], date[3], date[4], date[5], date[6]);
 260
 261        return rx8025_write_regs(rx8025->client, RX8025_REG_SEC, 7, date);
 262}
 263
 264static int rx8025_init_client(struct i2c_client *client, int *need_reset)
 265{
 266        struct rx8025_data *rx8025 = i2c_get_clientdata(client);
 267        u8 ctrl[2], ctrl2;
 268        int need_clear = 0;
 269        int err;
 270
 271        err = rx8025_read_regs(rx8025->client, RX8025_REG_CTRL1, 2, ctrl);
 272        if (err)
 273                goto out;
 274
 275        /* Keep test bit zero ! */
 276        rx8025->ctrl1 = ctrl[0] & ~RX8025_BIT_CTRL1_TEST;
 277
 278        if (ctrl[1] & RX8025_BIT_CTRL2_PON) {
 279                dev_warn(&client->dev, "power-on reset was detected, "
 280                         "you may have to readjust the clock\n");
 281                *need_reset = 1;
 282        }
 283
 284        if (ctrl[1] & RX8025_BIT_CTRL2_VDET) {
 285                dev_warn(&client->dev, "a power voltage drop was detected, "
 286                         "you may have to readjust the clock\n");
 287                *need_reset = 1;
 288        }
 289
 290        if (!(ctrl[1] & RX8025_BIT_CTRL2_XST)) {
 291                dev_warn(&client->dev, "Oscillation stop was detected,"
 292                         "you may have to readjust the clock\n");
 293                *need_reset = 1;
 294        }
 295
 296        if (ctrl[1] & (RX8025_BIT_CTRL2_DAFG | RX8025_BIT_CTRL2_WAFG)) {
 297                dev_warn(&client->dev, "Alarm was detected\n");
 298                need_clear = 1;
 299        }
 300
 301        if (!(ctrl[1] & RX8025_BIT_CTRL2_CTFG))
 302                need_clear = 1;
 303
 304        if (*need_reset || need_clear) {
 305                ctrl2 = ctrl[0];
 306                ctrl2 &= ~(RX8025_BIT_CTRL2_PON | RX8025_BIT_CTRL2_VDET |
 307                           RX8025_BIT_CTRL2_CTFG | RX8025_BIT_CTRL2_WAFG |
 308                           RX8025_BIT_CTRL2_DAFG);
 309                ctrl2 |= RX8025_BIT_CTRL2_XST;
 310
 311                err = rx8025_write_reg(client, RX8025_REG_CTRL2, ctrl2);
 312        }
 313out:
 314        return err;
 315}
 316
 317/* Alarm support */
 318static int rx8025_read_alarm(struct device *dev, struct rtc_wkalrm *t)
 319{
 320        struct rx8025_data *rx8025 = dev_get_drvdata(dev);
 321        struct i2c_client *client = rx8025->client;
 322        u8 ctrl2, ald[2];
 323        int err;
 324
 325        if (client->irq <= 0)
 326                return -EINVAL;
 327
 328        err = rx8025_read_regs(client, RX8025_REG_ALDMIN, 2, ald);
 329        if (err)
 330                return err;
 331
 332        err = rx8025_read_reg(client, RX8025_REG_CTRL2, &ctrl2);
 333        if (err)
 334                return err;
 335
 336        dev_dbg(dev, "%s: read alarm 0x%02x 0x%02x ctrl2 %02x\n",
 337                __func__, ald[0], ald[1], ctrl2);
 338
 339        /* Hardware alarms precision is 1 minute! */
 340        t->time.tm_sec = 0;
 341        t->time.tm_min = bcd2bin(ald[0] & 0x7f);
 342        if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
 343                t->time.tm_hour = bcd2bin(ald[1] & 0x3f);
 344        else
 345                t->time.tm_hour = bcd2bin(ald[1] & 0x1f) % 12
 346                        + (ald[1] & 0x20 ? 12 : 0);
 347
 348        t->time.tm_wday = -1;
 349        t->time.tm_mday = -1;
 350        t->time.tm_mon = -1;
 351        t->time.tm_year = -1;
 352
 353        dev_dbg(dev, "%s: date: %ds %dm %dh %dmd %dm %dy\n",
 354                __func__,
 355                t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
 356                t->time.tm_mday, t->time.tm_mon, t->time.tm_year);
 357        t->enabled = !!(rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE);
 358        t->pending = (ctrl2 & RX8025_BIT_CTRL2_DAFG) && t->enabled;
 359
 360        return err;
 361}
 362
 363static int rx8025_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 364{
 365        struct i2c_client *client = to_i2c_client(dev);
 366        struct rx8025_data *rx8025 = dev_get_drvdata(dev);
 367        u8 ald[2];
 368        int err;
 369
 370        if (client->irq <= 0)
 371                return -EINVAL;
 372
 373        /* Hardware alarm precision is 1 minute! */
 374        ald[0] = bin2bcd(t->time.tm_min);
 375        if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
 376                ald[1] = bin2bcd(t->time.tm_hour);
 377        else
 378                ald[1] = (t->time.tm_hour >= 12 ? 0x20 : 0)
 379                        | bin2bcd((t->time.tm_hour + 11) % 12 + 1);
 380
 381        dev_dbg(dev, "%s: write 0x%02x 0x%02x\n", __func__, ald[0], ald[1]);
 382
 383        if (rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE) {
 384                rx8025->ctrl1 &= ~RX8025_BIT_CTRL1_DALE;
 385                err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
 386                                       rx8025->ctrl1);
 387                if (err)
 388                        return err;
 389        }
 390        err = rx8025_write_regs(rx8025->client, RX8025_REG_ALDMIN, 2, ald);
 391        if (err)
 392                return err;
 393
 394        if (t->enabled) {
 395                rx8025->ctrl1 |= RX8025_BIT_CTRL1_DALE;
 396                err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
 397                                       rx8025->ctrl1);
 398                if (err)
 399                        return err;
 400        }
 401
 402        return 0;
 403}
 404
 405static int rx8025_alarm_irq_enable(struct device *dev, unsigned int enabled)
 406{
 407        struct rx8025_data *rx8025 = dev_get_drvdata(dev);
 408        u8 ctrl1;
 409        int err;
 410
 411        ctrl1 = rx8025->ctrl1;
 412        if (enabled)
 413                ctrl1 |= RX8025_BIT_CTRL1_DALE;
 414        else
 415                ctrl1 &= ~RX8025_BIT_CTRL1_DALE;
 416
 417        if (ctrl1 != rx8025->ctrl1) {
 418                rx8025->ctrl1 = ctrl1;
 419                err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
 420                                       rx8025->ctrl1);
 421                if (err)
 422                        return err;
 423        }
 424        return 0;
 425}
 426
 427static struct rtc_class_ops rx8025_rtc_ops = {
 428        .read_time = rx8025_get_time,
 429        .set_time = rx8025_set_time,
 430        .read_alarm = rx8025_read_alarm,
 431        .set_alarm = rx8025_set_alarm,
 432        .alarm_irq_enable = rx8025_alarm_irq_enable,
 433};
 434
 435/*
 436 * Clock precision adjustment support
 437 *
 438 * According to the RX8025 SA/NB application manual the frequency and
 439 * temperature characteristics can be approximated using the following
 440 * equation:
 441 *
 442 *   df = a * (ut - t)**2
 443 *
 444 *   df: Frequency deviation in any temperature
 445 *   a : Coefficient = (-35 +-5) * 10**-9
 446 *   ut: Ultimate temperature in degree = +25 +-5 degree
 447 *   t : Any temperature in degree
 448 *
 449 * Note that the clock adjustment in ppb must be entered (which is
 450 * the negative value of the deviation).
 451 */
 452static int rx8025_get_clock_adjust(struct device *dev, int *adj)
 453{
 454        struct i2c_client *client = to_i2c_client(dev);
 455        u8 digoff;
 456        int err;
 457
 458        err = rx8025_read_reg(client, RX8025_REG_DIGOFF, &digoff);
 459        if (err)
 460                return err;
 461
 462        *adj = digoff >= 64 ? digoff - 128 : digoff;
 463        if (*adj > 0)
 464                (*adj)--;
 465        *adj *= -RX8025_ADJ_RESOLUTION;
 466
 467        return 0;
 468}
 469
 470static int rx8025_set_clock_adjust(struct device *dev, int adj)
 471{
 472        struct i2c_client *client = to_i2c_client(dev);
 473        u8 digoff;
 474        int err;
 475
 476        adj /= -RX8025_ADJ_RESOLUTION;
 477        if (adj > RX8025_ADJ_DATA_MAX)
 478                adj = RX8025_ADJ_DATA_MAX;
 479        else if (adj < RX8025_ADJ_DATA_MIN)
 480                adj = RX8025_ADJ_DATA_MIN;
 481        else if (adj > 0)
 482                adj++;
 483        else if (adj < 0)
 484                adj += 128;
 485        digoff = adj;
 486
 487        err = rx8025_write_reg(client, RX8025_REG_DIGOFF, digoff);
 488        if (err)
 489                return err;
 490
 491        dev_dbg(dev, "%s: write 0x%02x\n", __func__, digoff);
 492
 493        return 0;
 494}
 495
 496static ssize_t rx8025_sysfs_show_clock_adjust(struct device *dev,
 497                                              struct device_attribute *attr,
 498                                              char *buf)
 499{
 500        int err, adj;
 501
 502        err = rx8025_get_clock_adjust(dev, &adj);
 503        if (err)
 504                return err;
 505
 506        return sprintf(buf, "%d\n", adj);
 507}
 508
 509static ssize_t rx8025_sysfs_store_clock_adjust(struct device *dev,
 510                                               struct device_attribute *attr,
 511                                               const char *buf, size_t count)
 512{
 513        int adj, err;
 514
 515        if (sscanf(buf, "%i", &adj) != 1)
 516                return -EINVAL;
 517
 518        err = rx8025_set_clock_adjust(dev, adj);
 519
 520        return err ? err : count;
 521}
 522
 523static DEVICE_ATTR(clock_adjust_ppb, S_IRUGO | S_IWUSR,
 524                   rx8025_sysfs_show_clock_adjust,
 525                   rx8025_sysfs_store_clock_adjust);
 526
 527static int rx8025_sysfs_register(struct device *dev)
 528{
 529        return device_create_file(dev, &dev_attr_clock_adjust_ppb);
 530}
 531
 532static void rx8025_sysfs_unregister(struct device *dev)
 533{
 534        device_remove_file(dev, &dev_attr_clock_adjust_ppb);
 535}
 536
 537static int __devinit rx8025_probe(struct i2c_client *client,
 538                                  const struct i2c_device_id *id)
 539{
 540        struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
 541        struct rx8025_data *rx8025;
 542        int err, need_reset = 0;
 543
 544        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
 545                                     | I2C_FUNC_SMBUS_I2C_BLOCK)) {
 546                dev_err(&adapter->dev,
 547                        "doesn't support required functionality\n");
 548                err = -EIO;
 549                goto errout;
 550        }
 551
 552        rx8025 = kzalloc(sizeof(*rx8025), GFP_KERNEL);
 553        if (!rx8025) {
 554                dev_err(&adapter->dev, "failed to alloc memory\n");
 555                err = -ENOMEM;
 556                goto errout;
 557        }
 558
 559        rx8025->client = client;
 560        i2c_set_clientdata(client, rx8025);
 561        INIT_WORK(&rx8025->work, rx8025_work);
 562
 563        err = rx8025_init_client(client, &need_reset);
 564        if (err)
 565                goto errout_free;
 566
 567        if (need_reset) {
 568                struct rtc_time tm;
 569                dev_info(&client->dev,
 570                         "bad conditions detected, resetting date\n");
 571                rtc_time_to_tm(0, &tm); /* 1970/1/1 */
 572                rx8025_set_time(&client->dev, &tm);
 573        }
 574
 575        rx8025->rtc = rtc_device_register(client->name, &client->dev,
 576                                          &rx8025_rtc_ops, THIS_MODULE);
 577        if (IS_ERR(rx8025->rtc)) {
 578                err = PTR_ERR(rx8025->rtc);
 579                dev_err(&client->dev, "unable to register the class device\n");
 580                goto errout_free;
 581        }
 582
 583        if (client->irq > 0) {
 584                dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
 585                err = request_irq(client->irq, rx8025_irq,
 586                                  0, "rx8025", client);
 587                if (err) {
 588                        dev_err(&client->dev, "unable to request IRQ\n");
 589                        goto errout_reg;
 590                }
 591        }
 592
 593        rx8025->rtc->irq_freq = 1;
 594        rx8025->rtc->max_user_freq = 1;
 595
 596        err = rx8025_sysfs_register(&client->dev);
 597        if (err)
 598                goto errout_irq;
 599
 600        return 0;
 601
 602errout_irq:
 603        if (client->irq > 0)
 604                free_irq(client->irq, client);
 605
 606errout_reg:
 607        rtc_device_unregister(rx8025->rtc);
 608
 609errout_free:
 610        kfree(rx8025);
 611
 612errout:
 613        dev_err(&adapter->dev, "probing for rx8025 failed\n");
 614        return err;
 615}
 616
 617static int __devexit rx8025_remove(struct i2c_client *client)
 618{
 619        struct rx8025_data *rx8025 = i2c_get_clientdata(client);
 620        struct mutex *lock = &rx8025->rtc->ops_lock;
 621
 622        if (client->irq > 0) {
 623                mutex_lock(lock);
 624                rx8025->exiting = 1;
 625                mutex_unlock(lock);
 626
 627                free_irq(client->irq, client);
 628                cancel_work_sync(&rx8025->work);
 629        }
 630
 631        rx8025_sysfs_unregister(&client->dev);
 632        rtc_device_unregister(rx8025->rtc);
 633        kfree(rx8025);
 634        return 0;
 635}
 636
 637static struct i2c_driver rx8025_driver = {
 638        .driver = {
 639                .name = "rtc-rx8025",
 640                .owner = THIS_MODULE,
 641        },
 642        .probe          = rx8025_probe,
 643        .remove         = __devexit_p(rx8025_remove),
 644        .id_table       = rx8025_id,
 645};
 646
 647static int __init rx8025_init(void)
 648{
 649        return i2c_add_driver(&rx8025_driver);
 650}
 651
 652static void __exit rx8025_exit(void)
 653{
 654        i2c_del_driver(&rx8025_driver);
 655}
 656
 657MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
 658MODULE_DESCRIPTION("RX-8025 SA/NB RTC driver");
 659MODULE_LICENSE("GPL");
 660
 661module_init(rx8025_init);
 662module_exit(rx8025_exit);
 663