linux/drivers/rtc/rtc-rs5c372.c
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   1/*
   2 * An I2C driver for Ricoh RS5C372, R2025S/D and RV5C38[67] RTCs
   3 *
   4 * Copyright (C) 2005 Pavel Mironchik <pmironchik@optifacio.net>
   5 * Copyright (C) 2006 Tower Technologies
   6 * Copyright (C) 2008 Paul Mundt
   7 *
   8 * This program is free software; you can redistribute it and/or modify
   9 * it under the terms of the GNU General Public License version 2 as
  10 * published by the Free Software Foundation.
  11 */
  12
  13#include <linux/i2c.h>
  14#include <linux/rtc.h>
  15#include <linux/bcd.h>
  16#include <linux/slab.h>
  17#include <linux/module.h>
  18
  19#define DRV_VERSION "0.6"
  20
  21
  22/*
  23 * Ricoh has a family of I2C based RTCs, which differ only slightly from
  24 * each other.  Differences center on pinout (e.g. how many interrupts,
  25 * output clock, etc) and how the control registers are used.  The '372
  26 * is significant only because that's the one this driver first supported.
  27 */
  28#define RS5C372_REG_SECS        0
  29#define RS5C372_REG_MINS        1
  30#define RS5C372_REG_HOURS       2
  31#define RS5C372_REG_WDAY        3
  32#define RS5C372_REG_DAY         4
  33#define RS5C372_REG_MONTH       5
  34#define RS5C372_REG_YEAR        6
  35#define RS5C372_REG_TRIM        7
  36#       define RS5C372_TRIM_XSL         0x80
  37#       define RS5C372_TRIM_MASK        0x7F
  38
  39#define RS5C_REG_ALARM_A_MIN    8                       /* or ALARM_W */
  40#define RS5C_REG_ALARM_A_HOURS  9
  41#define RS5C_REG_ALARM_A_WDAY   10
  42
  43#define RS5C_REG_ALARM_B_MIN    11                      /* or ALARM_D */
  44#define RS5C_REG_ALARM_B_HOURS  12
  45#define RS5C_REG_ALARM_B_WDAY   13                      /* (ALARM_B only) */
  46
  47#define RS5C_REG_CTRL1          14
  48#       define RS5C_CTRL1_AALE          (1 << 7)        /* or WALE */
  49#       define RS5C_CTRL1_BALE          (1 << 6)        /* or DALE */
  50#       define RV5C387_CTRL1_24         (1 << 5)
  51#       define RS5C372A_CTRL1_SL1       (1 << 5)
  52#       define RS5C_CTRL1_CT_MASK       (7 << 0)
  53#       define RS5C_CTRL1_CT0           (0 << 0)        /* no periodic irq */
  54#       define RS5C_CTRL1_CT4           (4 << 0)        /* 1 Hz level irq */
  55#define RS5C_REG_CTRL2          15
  56#       define RS5C372_CTRL2_24         (1 << 5)
  57#       define R2025_CTRL2_XST          (1 << 5)
  58#       define RS5C_CTRL2_XSTP          (1 << 4)        /* only if !R2025S/D */
  59#       define RS5C_CTRL2_CTFG          (1 << 2)
  60#       define RS5C_CTRL2_AAFG          (1 << 1)        /* or WAFG */
  61#       define RS5C_CTRL2_BAFG          (1 << 0)        /* or DAFG */
  62
  63
  64/* to read (style 1) or write registers starting at R */
  65#define RS5C_ADDR(R)            (((R) << 4) | 0)
  66
  67
  68enum rtc_type {
  69        rtc_undef = 0,
  70        rtc_r2025sd,
  71        rtc_rs5c372a,
  72        rtc_rs5c372b,
  73        rtc_rv5c386,
  74        rtc_rv5c387a,
  75};
  76
  77static const struct i2c_device_id rs5c372_id[] = {
  78        { "r2025sd", rtc_r2025sd },
  79        { "rs5c372a", rtc_rs5c372a },
  80        { "rs5c372b", rtc_rs5c372b },
  81        { "rv5c386", rtc_rv5c386 },
  82        { "rv5c387a", rtc_rv5c387a },
  83        { }
  84};
  85MODULE_DEVICE_TABLE(i2c, rs5c372_id);
  86
  87/* REVISIT:  this assumes that:
  88 *  - we're in the 21st century, so it's safe to ignore the century
  89 *    bit for rv5c38[67] (REG_MONTH bit 7);
  90 *  - we should use ALARM_A not ALARM_B (may be wrong on some boards)
  91 */
  92struct rs5c372 {
  93        struct i2c_client       *client;
  94        struct rtc_device       *rtc;
  95        enum rtc_type           type;
  96        unsigned                time24:1;
  97        unsigned                has_irq:1;
  98        unsigned                smbus:1;
  99        char                    buf[17];
 100        char                    *regs;
 101};
 102
 103static int rs5c_get_regs(struct rs5c372 *rs5c)
 104{
 105        struct i2c_client       *client = rs5c->client;
 106        struct i2c_msg          msgs[] = {
 107                {
 108                        .addr = client->addr,
 109                        .flags = I2C_M_RD,
 110                        .len = sizeof(rs5c->buf),
 111                        .buf = rs5c->buf
 112                },
 113        };
 114
 115        /* This implements the third reading method from the datasheet, using
 116         * an internal address that's reset after each transaction (by STOP)
 117         * to 0x0f ... so we read extra registers, and skip the first one.
 118         *
 119         * The first method doesn't work with the iop3xx adapter driver, on at
 120         * least 80219 chips; this works around that bug.
 121         *
 122         * The third method on the other hand doesn't work for the SMBus-only
 123         * configurations, so we use the the first method there, stripping off
 124         * the extra register in the process.
 125         */
 126        if (rs5c->smbus) {
 127                int addr = RS5C_ADDR(RS5C372_REG_SECS);
 128                int size = sizeof(rs5c->buf) - 1;
 129
 130                if (i2c_smbus_read_i2c_block_data(client, addr, size,
 131                                                  rs5c->buf + 1) != size) {
 132                        dev_warn(&client->dev, "can't read registers\n");
 133                        return -EIO;
 134                }
 135        } else {
 136                if ((i2c_transfer(client->adapter, msgs, 1)) != 1) {
 137                        dev_warn(&client->dev, "can't read registers\n");
 138                        return -EIO;
 139                }
 140        }
 141
 142        dev_dbg(&client->dev,
 143                "%02x %02x %02x (%02x) %02x %02x %02x (%02x), "
 144                "%02x %02x %02x, %02x %02x %02x; %02x %02x\n",
 145                rs5c->regs[0],  rs5c->regs[1],  rs5c->regs[2],  rs5c->regs[3],
 146                rs5c->regs[4],  rs5c->regs[5],  rs5c->regs[6],  rs5c->regs[7],
 147                rs5c->regs[8],  rs5c->regs[9],  rs5c->regs[10], rs5c->regs[11],
 148                rs5c->regs[12], rs5c->regs[13], rs5c->regs[14], rs5c->regs[15]);
 149
 150        return 0;
 151}
 152
 153static unsigned rs5c_reg2hr(struct rs5c372 *rs5c, unsigned reg)
 154{
 155        unsigned        hour;
 156
 157        if (rs5c->time24)
 158                return bcd2bin(reg & 0x3f);
 159
 160        hour = bcd2bin(reg & 0x1f);
 161        if (hour == 12)
 162                hour = 0;
 163        if (reg & 0x20)
 164                hour += 12;
 165        return hour;
 166}
 167
 168static unsigned rs5c_hr2reg(struct rs5c372 *rs5c, unsigned hour)
 169{
 170        if (rs5c->time24)
 171                return bin2bcd(hour);
 172
 173        if (hour > 12)
 174                return 0x20 | bin2bcd(hour - 12);
 175        if (hour == 12)
 176                return 0x20 | bin2bcd(12);
 177        if (hour == 0)
 178                return bin2bcd(12);
 179        return bin2bcd(hour);
 180}
 181
 182static int rs5c372_get_datetime(struct i2c_client *client, struct rtc_time *tm)
 183{
 184        struct rs5c372  *rs5c = i2c_get_clientdata(client);
 185        int             status = rs5c_get_regs(rs5c);
 186
 187        if (status < 0)
 188                return status;
 189
 190        tm->tm_sec = bcd2bin(rs5c->regs[RS5C372_REG_SECS] & 0x7f);
 191        tm->tm_min = bcd2bin(rs5c->regs[RS5C372_REG_MINS] & 0x7f);
 192        tm->tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C372_REG_HOURS]);
 193
 194        tm->tm_wday = bcd2bin(rs5c->regs[RS5C372_REG_WDAY] & 0x07);
 195        tm->tm_mday = bcd2bin(rs5c->regs[RS5C372_REG_DAY] & 0x3f);
 196
 197        /* tm->tm_mon is zero-based */
 198        tm->tm_mon = bcd2bin(rs5c->regs[RS5C372_REG_MONTH] & 0x1f) - 1;
 199
 200        /* year is 1900 + tm->tm_year */
 201        tm->tm_year = bcd2bin(rs5c->regs[RS5C372_REG_YEAR]) + 100;
 202
 203        dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
 204                "mday=%d, mon=%d, year=%d, wday=%d\n",
 205                __func__,
 206                tm->tm_sec, tm->tm_min, tm->tm_hour,
 207                tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
 208
 209        /* rtc might need initialization */
 210        return rtc_valid_tm(tm);
 211}
 212
 213static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm)
 214{
 215        struct rs5c372  *rs5c = i2c_get_clientdata(client);
 216        unsigned char   buf[7];
 217        int             addr;
 218
 219        dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d "
 220                "mday=%d, mon=%d, year=%d, wday=%d\n",
 221                __func__,
 222                tm->tm_sec, tm->tm_min, tm->tm_hour,
 223                tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
 224
 225        addr   = RS5C_ADDR(RS5C372_REG_SECS);
 226        buf[0] = bin2bcd(tm->tm_sec);
 227        buf[1] = bin2bcd(tm->tm_min);
 228        buf[2] = rs5c_hr2reg(rs5c, tm->tm_hour);
 229        buf[3] = bin2bcd(tm->tm_wday);
 230        buf[4] = bin2bcd(tm->tm_mday);
 231        buf[5] = bin2bcd(tm->tm_mon + 1);
 232        buf[6] = bin2bcd(tm->tm_year - 100);
 233
 234        if (i2c_smbus_write_i2c_block_data(client, addr, sizeof(buf), buf) < 0) {
 235                dev_err(&client->dev, "%s: write error\n", __func__);
 236                return -EIO;
 237        }
 238
 239        return 0;
 240}
 241
 242#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
 243#define NEED_TRIM
 244#endif
 245
 246#if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
 247#define NEED_TRIM
 248#endif
 249
 250#ifdef  NEED_TRIM
 251static int rs5c372_get_trim(struct i2c_client *client, int *osc, int *trim)
 252{
 253        struct rs5c372 *rs5c372 = i2c_get_clientdata(client);
 254        u8 tmp = rs5c372->regs[RS5C372_REG_TRIM];
 255
 256        if (osc)
 257                *osc = (tmp & RS5C372_TRIM_XSL) ? 32000 : 32768;
 258
 259        if (trim) {
 260                dev_dbg(&client->dev, "%s: raw trim=%x\n", __func__, tmp);
 261                tmp &= RS5C372_TRIM_MASK;
 262                if (tmp & 0x3e) {
 263                        int t = tmp & 0x3f;
 264
 265                        if (tmp & 0x40)
 266                                t = (~t | (s8)0xc0) + 1;
 267                        else
 268                                t = t - 1;
 269
 270                        tmp = t * 2;
 271                } else
 272                        tmp = 0;
 273                *trim = tmp;
 274        }
 275
 276        return 0;
 277}
 278#endif
 279
 280static int rs5c372_rtc_read_time(struct device *dev, struct rtc_time *tm)
 281{
 282        return rs5c372_get_datetime(to_i2c_client(dev), tm);
 283}
 284
 285static int rs5c372_rtc_set_time(struct device *dev, struct rtc_time *tm)
 286{
 287        return rs5c372_set_datetime(to_i2c_client(dev), tm);
 288}
 289
 290
 291static int rs5c_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
 292{
 293        struct i2c_client       *client = to_i2c_client(dev);
 294        struct rs5c372          *rs5c = i2c_get_clientdata(client);
 295        unsigned char           buf;
 296        int                     status, addr;
 297
 298        buf = rs5c->regs[RS5C_REG_CTRL1];
 299
 300        if (!rs5c->has_irq)
 301                return -EINVAL;
 302
 303        status = rs5c_get_regs(rs5c);
 304        if (status < 0)
 305                return status;
 306
 307        addr = RS5C_ADDR(RS5C_REG_CTRL1);
 308        if (enabled)
 309                buf |= RS5C_CTRL1_AALE;
 310        else
 311                buf &= ~RS5C_CTRL1_AALE;
 312
 313        if (i2c_smbus_write_byte_data(client, addr, buf) < 0) {
 314                dev_warn(dev, "can't update alarm\n");
 315                status = -EIO;
 316        } else
 317                rs5c->regs[RS5C_REG_CTRL1] = buf;
 318
 319        return status;
 320}
 321
 322
 323/* NOTE:  Since RTC_WKALM_{RD,SET} were originally defined for EFI,
 324 * which only exposes a polled programming interface; and since
 325 * these calls map directly to those EFI requests; we don't demand
 326 * we have an IRQ for this chip when we go through this API.
 327 *
 328 * The older x86_pc derived RTC_ALM_{READ,SET} calls require irqs
 329 * though, managed through RTC_AIE_{ON,OFF} requests.
 330 */
 331
 332static int rs5c_read_alarm(struct device *dev, struct rtc_wkalrm *t)
 333{
 334        struct i2c_client       *client = to_i2c_client(dev);
 335        struct rs5c372          *rs5c = i2c_get_clientdata(client);
 336        int                     status;
 337
 338        status = rs5c_get_regs(rs5c);
 339        if (status < 0)
 340                return status;
 341
 342        /* report alarm time */
 343        t->time.tm_sec = 0;
 344        t->time.tm_min = bcd2bin(rs5c->regs[RS5C_REG_ALARM_A_MIN] & 0x7f);
 345        t->time.tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C_REG_ALARM_A_HOURS]);
 346        t->time.tm_mday = -1;
 347        t->time.tm_mon = -1;
 348        t->time.tm_year = -1;
 349        t->time.tm_wday = -1;
 350        t->time.tm_yday = -1;
 351        t->time.tm_isdst = -1;
 352
 353        /* ... and status */
 354        t->enabled = !!(rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE);
 355        t->pending = !!(rs5c->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_AAFG);
 356
 357        return 0;
 358}
 359
 360static int rs5c_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 361{
 362        struct i2c_client       *client = to_i2c_client(dev);
 363        struct rs5c372          *rs5c = i2c_get_clientdata(client);
 364        int                     status, addr, i;
 365        unsigned char           buf[3];
 366
 367        /* only handle up to 24 hours in the future, like RTC_ALM_SET */
 368        if (t->time.tm_mday != -1
 369                        || t->time.tm_mon != -1
 370                        || t->time.tm_year != -1)
 371                return -EINVAL;
 372
 373        /* REVISIT: round up tm_sec */
 374
 375        /* if needed, disable irq (clears pending status) */
 376        status = rs5c_get_regs(rs5c);
 377        if (status < 0)
 378                return status;
 379        if (rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE) {
 380                addr = RS5C_ADDR(RS5C_REG_CTRL1);
 381                buf[0] = rs5c->regs[RS5C_REG_CTRL1] & ~RS5C_CTRL1_AALE;
 382                if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0) {
 383                        dev_dbg(dev, "can't disable alarm\n");
 384                        return -EIO;
 385                }
 386                rs5c->regs[RS5C_REG_CTRL1] = buf[0];
 387        }
 388
 389        /* set alarm */
 390        buf[0] = bin2bcd(t->time.tm_min);
 391        buf[1] = rs5c_hr2reg(rs5c, t->time.tm_hour);
 392        buf[2] = 0x7f;  /* any/all days */
 393
 394        for (i = 0; i < sizeof(buf); i++) {
 395                addr = RS5C_ADDR(RS5C_REG_ALARM_A_MIN + i);
 396                if (i2c_smbus_write_byte_data(client, addr, buf[i]) < 0) {
 397                        dev_dbg(dev, "can't set alarm time\n");
 398                        return -EIO;
 399                }
 400        }
 401
 402        /* ... and maybe enable its irq */
 403        if (t->enabled) {
 404                addr = RS5C_ADDR(RS5C_REG_CTRL1);
 405                buf[0] = rs5c->regs[RS5C_REG_CTRL1] | RS5C_CTRL1_AALE;
 406                if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0)
 407                        dev_warn(dev, "can't enable alarm\n");
 408                rs5c->regs[RS5C_REG_CTRL1] = buf[0];
 409        }
 410
 411        return 0;
 412}
 413
 414#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
 415
 416static int rs5c372_rtc_proc(struct device *dev, struct seq_file *seq)
 417{
 418        int err, osc, trim;
 419
 420        err = rs5c372_get_trim(to_i2c_client(dev), &osc, &trim);
 421        if (err == 0) {
 422                seq_printf(seq, "crystal\t\t: %d.%03d KHz\n",
 423                                osc / 1000, osc % 1000);
 424                seq_printf(seq, "trim\t\t: %d\n", trim);
 425        }
 426
 427        return 0;
 428}
 429
 430#else
 431#define rs5c372_rtc_proc        NULL
 432#endif
 433
 434static const struct rtc_class_ops rs5c372_rtc_ops = {
 435        .proc           = rs5c372_rtc_proc,
 436        .read_time      = rs5c372_rtc_read_time,
 437        .set_time       = rs5c372_rtc_set_time,
 438        .read_alarm     = rs5c_read_alarm,
 439        .set_alarm      = rs5c_set_alarm,
 440        .alarm_irq_enable = rs5c_rtc_alarm_irq_enable,
 441};
 442
 443#if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
 444
 445static ssize_t rs5c372_sysfs_show_trim(struct device *dev,
 446                                struct device_attribute *attr, char *buf)
 447{
 448        int err, trim;
 449
 450        err = rs5c372_get_trim(to_i2c_client(dev), NULL, &trim);
 451        if (err)
 452                return err;
 453
 454        return sprintf(buf, "%d\n", trim);
 455}
 456static DEVICE_ATTR(trim, S_IRUGO, rs5c372_sysfs_show_trim, NULL);
 457
 458static ssize_t rs5c372_sysfs_show_osc(struct device *dev,
 459                                struct device_attribute *attr, char *buf)
 460{
 461        int err, osc;
 462
 463        err = rs5c372_get_trim(to_i2c_client(dev), &osc, NULL);
 464        if (err)
 465                return err;
 466
 467        return sprintf(buf, "%d.%03d KHz\n", osc / 1000, osc % 1000);
 468}
 469static DEVICE_ATTR(osc, S_IRUGO, rs5c372_sysfs_show_osc, NULL);
 470
 471static int rs5c_sysfs_register(struct device *dev)
 472{
 473        int err;
 474
 475        err = device_create_file(dev, &dev_attr_trim);
 476        if (err)
 477                return err;
 478        err = device_create_file(dev, &dev_attr_osc);
 479        if (err)
 480                device_remove_file(dev, &dev_attr_trim);
 481
 482        return err;
 483}
 484
 485static void rs5c_sysfs_unregister(struct device *dev)
 486{
 487        device_remove_file(dev, &dev_attr_trim);
 488        device_remove_file(dev, &dev_attr_osc);
 489}
 490
 491#else
 492static int rs5c_sysfs_register(struct device *dev)
 493{
 494        return 0;
 495}
 496
 497static void rs5c_sysfs_unregister(struct device *dev)
 498{
 499        /* nothing */
 500}
 501#endif  /* SYSFS */
 502
 503static struct i2c_driver rs5c372_driver;
 504
 505static int rs5c_oscillator_setup(struct rs5c372 *rs5c372)
 506{
 507        unsigned char buf[2];
 508        int addr, i, ret = 0;
 509
 510        if (rs5c372->type == rtc_r2025sd) {
 511                if (!(rs5c372->regs[RS5C_REG_CTRL2] & R2025_CTRL2_XST))
 512                        return ret;
 513                rs5c372->regs[RS5C_REG_CTRL2] &= ~R2025_CTRL2_XST;
 514        } else {
 515                if (!(rs5c372->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_XSTP))
 516                        return ret;
 517                rs5c372->regs[RS5C_REG_CTRL2] &= ~RS5C_CTRL2_XSTP;
 518        }
 519
 520        addr   = RS5C_ADDR(RS5C_REG_CTRL1);
 521        buf[0] = rs5c372->regs[RS5C_REG_CTRL1];
 522        buf[1] = rs5c372->regs[RS5C_REG_CTRL2];
 523
 524        /* use 24hr mode */
 525        switch (rs5c372->type) {
 526        case rtc_rs5c372a:
 527        case rtc_rs5c372b:
 528                buf[1] |= RS5C372_CTRL2_24;
 529                rs5c372->time24 = 1;
 530                break;
 531        case rtc_r2025sd:
 532        case rtc_rv5c386:
 533        case rtc_rv5c387a:
 534                buf[0] |= RV5C387_CTRL1_24;
 535                rs5c372->time24 = 1;
 536                break;
 537        default:
 538                /* impossible */
 539                break;
 540        }
 541
 542        for (i = 0; i < sizeof(buf); i++) {
 543                addr = RS5C_ADDR(RS5C_REG_CTRL1 + i);
 544                ret = i2c_smbus_write_byte_data(rs5c372->client, addr, buf[i]);
 545                if (unlikely(ret < 0))
 546                        return ret;
 547        }
 548
 549        rs5c372->regs[RS5C_REG_CTRL1] = buf[0];
 550        rs5c372->regs[RS5C_REG_CTRL2] = buf[1];
 551
 552        return 0;
 553}
 554
 555static int rs5c372_probe(struct i2c_client *client,
 556                         const struct i2c_device_id *id)
 557{
 558        int err = 0;
 559        int smbus_mode = 0;
 560        struct rs5c372 *rs5c372;
 561        struct rtc_time tm;
 562
 563        dev_dbg(&client->dev, "%s\n", __func__);
 564
 565        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
 566                        I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK)) {
 567                /*
 568                 * If we don't have any master mode adapter, try breaking
 569                 * it down in to the barest of capabilities.
 570                 */
 571                if (i2c_check_functionality(client->adapter,
 572                                I2C_FUNC_SMBUS_BYTE_DATA |
 573                                I2C_FUNC_SMBUS_I2C_BLOCK))
 574                        smbus_mode = 1;
 575                else {
 576                        /* Still no good, give up */
 577                        err = -ENODEV;
 578                        goto exit;
 579                }
 580        }
 581
 582        if (!(rs5c372 = kzalloc(sizeof(struct rs5c372), GFP_KERNEL))) {
 583                err = -ENOMEM;
 584                goto exit;
 585        }
 586
 587        rs5c372->client = client;
 588        i2c_set_clientdata(client, rs5c372);
 589        rs5c372->type = id->driver_data;
 590
 591        /* we read registers 0x0f then 0x00-0x0f; skip the first one */
 592        rs5c372->regs = &rs5c372->buf[1];
 593        rs5c372->smbus = smbus_mode;
 594
 595        err = rs5c_get_regs(rs5c372);
 596        if (err < 0)
 597                goto exit_kfree;
 598
 599        /* clock may be set for am/pm or 24 hr time */
 600        switch (rs5c372->type) {
 601        case rtc_rs5c372a:
 602        case rtc_rs5c372b:
 603                /* alarm uses ALARM_A; and nINTRA on 372a, nINTR on 372b.
 604                 * so does periodic irq, except some 327a modes.
 605                 */
 606                if (rs5c372->regs[RS5C_REG_CTRL2] & RS5C372_CTRL2_24)
 607                        rs5c372->time24 = 1;
 608                break;
 609        case rtc_r2025sd:
 610        case rtc_rv5c386:
 611        case rtc_rv5c387a:
 612                if (rs5c372->regs[RS5C_REG_CTRL1] & RV5C387_CTRL1_24)
 613                        rs5c372->time24 = 1;
 614                /* alarm uses ALARM_W; and nINTRB for alarm and periodic
 615                 * irq, on both 386 and 387
 616                 */
 617                break;
 618        default:
 619                dev_err(&client->dev, "unknown RTC type\n");
 620                goto exit_kfree;
 621        }
 622
 623        /* if the oscillator lost power and no other software (like
 624         * the bootloader) set it up, do it here.
 625         *
 626         * The R2025S/D does this a little differently than the other
 627         * parts, so we special case that..
 628         */
 629        err = rs5c_oscillator_setup(rs5c372);
 630        if (unlikely(err < 0)) {
 631                dev_err(&client->dev, "setup error\n");
 632                goto exit_kfree;
 633        }
 634
 635        if (rs5c372_get_datetime(client, &tm) < 0)
 636                dev_warn(&client->dev, "clock needs to be set\n");
 637
 638        dev_info(&client->dev, "%s found, %s, driver version " DRV_VERSION "\n",
 639                        ({ char *s; switch (rs5c372->type) {
 640                        case rtc_r2025sd:       s = "r2025sd"; break;
 641                        case rtc_rs5c372a:      s = "rs5c372a"; break;
 642                        case rtc_rs5c372b:      s = "rs5c372b"; break;
 643                        case rtc_rv5c386:       s = "rv5c386"; break;
 644                        case rtc_rv5c387a:      s = "rv5c387a"; break;
 645                        default:                s = "chip"; break;
 646                        }; s;}),
 647                        rs5c372->time24 ? "24hr" : "am/pm"
 648                        );
 649
 650        /* REVISIT use client->irq to register alarm irq ... */
 651
 652        rs5c372->rtc = rtc_device_register(rs5c372_driver.driver.name,
 653                                &client->dev, &rs5c372_rtc_ops, THIS_MODULE);
 654
 655        if (IS_ERR(rs5c372->rtc)) {
 656                err = PTR_ERR(rs5c372->rtc);
 657                goto exit_kfree;
 658        }
 659
 660        err = rs5c_sysfs_register(&client->dev);
 661        if (err)
 662                goto exit_devreg;
 663
 664        return 0;
 665
 666exit_devreg:
 667        rtc_device_unregister(rs5c372->rtc);
 668
 669exit_kfree:
 670        kfree(rs5c372);
 671
 672exit:
 673        return err;
 674}
 675
 676static int rs5c372_remove(struct i2c_client *client)
 677{
 678        struct rs5c372 *rs5c372 = i2c_get_clientdata(client);
 679
 680        rtc_device_unregister(rs5c372->rtc);
 681        rs5c_sysfs_unregister(&client->dev);
 682        kfree(rs5c372);
 683        return 0;
 684}
 685
 686static struct i2c_driver rs5c372_driver = {
 687        .driver         = {
 688                .name   = "rtc-rs5c372",
 689        },
 690        .probe          = rs5c372_probe,
 691        .remove         = rs5c372_remove,
 692        .id_table       = rs5c372_id,
 693};
 694
 695module_i2c_driver(rs5c372_driver);
 696
 697MODULE_AUTHOR(
 698                "Pavel Mironchik <pmironchik@optifacio.net>, "
 699                "Alessandro Zummo <a.zummo@towertech.it>, "
 700                "Paul Mundt <lethal@linux-sh.org>");
 701MODULE_DESCRIPTION("Ricoh RS5C372 RTC driver");
 702MODULE_LICENSE("GPL");
 703MODULE_VERSION(DRV_VERSION);
 704
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