err.no Git - linux-2.6/blob - drivers/rtc/rtc-rs5c372.c

   1 /*
   2  * An I2C driver for Ricoh RS5C372 and RV5C38[67] RTCs
   3  *
   4  * Copyright (C) 2005 Pavel Mironchik <pmironchik@optifacio.net>
   5  * Copyright (C) 2006 Tower Technologies
   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/i2c.h>
  13 #include <linux/rtc.h>
  14 #include <linux/bcd.h>
  15
  16 #define DRV_VERSION "0.5"
  17
  18
  19 /*
  20  * Ricoh has a family of I2C based RTCs, which differ only slightly from
  21  * each other.  Differences center on pinout (e.g. how many interrupts,
  22  * output clock, etc) and how the control registers are used.  The '372
  23  * is significant only because that's the one this driver first supported.
  24  */
  25 #define RS5C372_REG_SECS        0
  26 #define RS5C372_REG_MINS        1
  27 #define RS5C372_REG_HOURS       2
  28 #define RS5C372_REG_WDAY        3
  29 #define RS5C372_REG_DAY         4
  30 #define RS5C372_REG_MONTH       5
  31 #define RS5C372_REG_YEAR        6
  32 #define RS5C372_REG_TRIM        7
  33 #       define RS5C372_TRIM_XSL         0x80
  34 #       define RS5C372_TRIM_MASK        0x7F
  35
  36 #define RS5C_REG_ALARM_A_MIN    8                       /* or ALARM_W */
  37 #define RS5C_REG_ALARM_A_HOURS  9
  38 #define RS5C_REG_ALARM_A_WDAY   10
  39
  40 #define RS5C_REG_ALARM_B_MIN    11                      /* or ALARM_D */
  41 #define RS5C_REG_ALARM_B_HOURS  12
  42 #define RS5C_REG_ALARM_B_WDAY   13                      /* (ALARM_B only) */
  43
  44 #define RS5C_REG_CTRL1          14
  45 #       define RS5C_CTRL1_AALE          (1 << 7)        /* or WALE */
  46 #       define RS5C_CTRL1_BALE          (1 << 6)        /* or DALE */
  47 #       define RV5C387_CTRL1_24         (1 << 5)
  48 #       define RS5C372A_CTRL1_SL1       (1 << 5)
  49 #       define RS5C_CTRL1_CT_MASK       (7 << 0)
  50 #       define RS5C_CTRL1_CT0           (0 << 0)        /* no periodic irq */
  51 #       define RS5C_CTRL1_CT4           (4 << 0)        /* 1 Hz level irq */
  52 #define RS5C_REG_CTRL2          15
  53 #       define RS5C372_CTRL2_24         (1 << 5)
  54 #       define RS5C_CTRL2_XSTP          (1 << 4)
  55 #       define RS5C_CTRL2_CTFG          (1 << 2)
  56 #       define RS5C_CTRL2_AAFG          (1 << 1)        /* or WAFG */
  57 #       define RS5C_CTRL2_BAFG          (1 << 0)        /* or DAFG */
  58
  59
  60 /* to read (style 1) or write registers starting at R */
  61 #define RS5C_ADDR(R)            (((R) << 4) | 0)
  62
  63
  64 enum rtc_type {
  65         rtc_undef = 0,
  66         rtc_rs5c372a,
  67         rtc_rs5c372b,
  68         rtc_rv5c386,
  69         rtc_rv5c387a,
  70 };
  71
  72 static const struct i2c_device_id rs5c372_id[] = {
  73         { "rs5c372a", rtc_rs5c372a },
  74         { "rs5c372b", rtc_rs5c372b },
  75         { "rv5c386", rtc_rv5c386 },
  76         { "rv5c387a", rtc_rv5c387a },
  77         { }
  78 };
  79 MODULE_DEVICE_TABLE(i2c, rs5c372_id);
  80
  81 /* REVISIT:  this assumes that:
  82  *  - we're in the 21st century, so it's safe to ignore the century
  83  *    bit for rv5c38[67] (REG_MONTH bit 7);
  84  *  - we should use ALARM_A not ALARM_B (may be wrong on some boards)
  85  */
  86 struct rs5c372 {
  87         struct i2c_client       *client;
  88         struct rtc_device       *rtc;
  89         enum rtc_type           type;
  90         unsigned                time24:1;
  91         unsigned                has_irq:1;
  92         char                    buf[17];
  93         char                    *regs;
  94 };
  95
  96 static int rs5c_get_regs(struct rs5c372 *rs5c)
  97 {
  98         struct i2c_client       *client = rs5c->client;
  99         struct i2c_msg          msgs[] = {
 100                 { client->addr, I2C_M_RD, sizeof rs5c->buf, rs5c->buf },
 101         };
 102
 103         /* This implements the third reading method from the datasheet, using
 104          * an internal address that's reset after each transaction (by STOP)
 105          * to 0x0f ... so we read extra registers, and skip the first one.
 106          *
 107          * The first method doesn't work with the iop3xx adapter driver, on at
 108          * least 80219 chips; this works around that bug.
 109          */
 110         if ((i2c_transfer(client->adapter, msgs, 1)) != 1) {
 111                 dev_warn(&client->dev, "can't read registers\n");
 112                 return -EIO;
 113         }
 114
 115         dev_dbg(&client->dev,
 116                 "%02x %02x %02x (%02x) %02x %02x %02x (%02x), "
 117                 "%02x %02x %02x, %02x %02x %02x; %02x %02x\n",
 118                 rs5c->regs[0],  rs5c->regs[1],  rs5c->regs[2],  rs5c->regs[3],
 119                 rs5c->regs[4],  rs5c->regs[5],  rs5c->regs[6],  rs5c->regs[7],
 120                 rs5c->regs[8],  rs5c->regs[9],  rs5c->regs[10], rs5c->regs[11],
 121                 rs5c->regs[12], rs5c->regs[13], rs5c->regs[14], rs5c->regs[15]);
 122
 123         return 0;
 124 }
 125
 126 static unsigned rs5c_reg2hr(struct rs5c372 *rs5c, unsigned reg)
 127 {
 128         unsigned        hour;
 129
 130         if (rs5c->time24)
 131                 return BCD2BIN(reg & 0x3f);
 132
 133         hour = BCD2BIN(reg & 0x1f);
 134         if (hour == 12)
 135                 hour = 0;
 136         if (reg & 0x20)
 137                 hour += 12;
 138         return hour;
 139 }
 140
 141 static unsigned rs5c_hr2reg(struct rs5c372 *rs5c, unsigned hour)
 142 {
 143         if (rs5c->time24)
 144                 return BIN2BCD(hour);
 145
 146         if (hour > 12)
 147                 return 0x20 | BIN2BCD(hour - 12);
 148         if (hour == 12)
 149                 return 0x20 | BIN2BCD(12);
 150         if (hour == 0)
 151                 return BIN2BCD(12);
 152         return BIN2BCD(hour);
 153 }
 154
 155 static int rs5c372_get_datetime(struct i2c_client *client, struct rtc_time *tm)
 156 {
 157         struct rs5c372  *rs5c = i2c_get_clientdata(client);
 158         int             status = rs5c_get_regs(rs5c);
 159
 160         if (status < 0)
 161                 return status;
 162
 163         tm->tm_sec = BCD2BIN(rs5c->regs[RS5C372_REG_SECS] & 0x7f);
 164         tm->tm_min = BCD2BIN(rs5c->regs[RS5C372_REG_MINS] & 0x7f);
 165         tm->tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C372_REG_HOURS]);
 166
 167         tm->tm_wday = BCD2BIN(rs5c->regs[RS5C372_REG_WDAY] & 0x07);
 168         tm->tm_mday = BCD2BIN(rs5c->regs[RS5C372_REG_DAY] & 0x3f);
 169
 170         /* tm->tm_mon is zero-based */
 171         tm->tm_mon = BCD2BIN(rs5c->regs[RS5C372_REG_MONTH] & 0x1f) - 1;
 172
 173         /* year is 1900 + tm->tm_year */
 174         tm->tm_year = BCD2BIN(rs5c->regs[RS5C372_REG_YEAR]) + 100;
 175
 176         dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
 177                 "mday=%d, mon=%d, year=%d, wday=%d\n",
 178                 __func__,
 179                 tm->tm_sec, tm->tm_min, tm->tm_hour,
 180                 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
 181
 182         /* rtc might need initialization */
 183         return rtc_valid_tm(tm);
 184 }
 185
 186 static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm)
 187 {
 188         struct rs5c372  *rs5c = i2c_get_clientdata(client);
 189         unsigned char   buf[8];
 190
 191         dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d "
 192                 "mday=%d, mon=%d, year=%d, wday=%d\n",
 193                 __func__,
 194                 tm->tm_sec, tm->tm_min, tm->tm_hour,
 195                 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
 196
 197         buf[0] = RS5C_ADDR(RS5C372_REG_SECS);
 198         buf[1] = BIN2BCD(tm->tm_sec);
 199         buf[2] = BIN2BCD(tm->tm_min);
 200         buf[3] = rs5c_hr2reg(rs5c, tm->tm_hour);
 201         buf[4] = BIN2BCD(tm->tm_wday);
 202         buf[5] = BIN2BCD(tm->tm_mday);
 203         buf[6] = BIN2BCD(tm->tm_mon + 1);
 204         buf[7] = BIN2BCD(tm->tm_year - 100);
 205
 206         if ((i2c_master_send(client, buf, 8)) != 8) {
 207                 dev_err(&client->dev, "%s: write error\n", __func__);
 208                 return -EIO;
 209         }
 210
 211         return 0;
 212 }
 213
 214 #if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
 215 #define NEED_TRIM
 216 #endif
 217
 218 #if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
 219 #define NEED_TRIM
 220 #endif
 221
 222 #ifdef  NEED_TRIM
 223 static int rs5c372_get_trim(struct i2c_client *client, int *osc, int *trim)
 224 {
 225         struct rs5c372 *rs5c372 = i2c_get_clientdata(client);
 226         u8 tmp = rs5c372->regs[RS5C372_REG_TRIM];
 227
 228         if (osc)
 229                 *osc = (tmp & RS5C372_TRIM_XSL) ? 32000 : 32768;
 230
 231         if (trim) {
 232                 dev_dbg(&client->dev, "%s: raw trim=%x\n", __func__, tmp);
 233                 tmp &= RS5C372_TRIM_MASK;
 234                 if (tmp & 0x3e) {
 235                         int t = tmp & 0x3f;
 236
 237                         if (tmp & 0x40)
 238                                 t = (~t | (s8)0xc0) + 1;
 239                         else
 240                                 t = t - 1;
 241
 242                         tmp = t * 2;
 243                 } else
 244                         tmp = 0;
 245                 *trim = tmp;
 246         }
 247
 248         return 0;
 249 }
 250 #endif
 251
 252 static int rs5c372_rtc_read_time(struct device *dev, struct rtc_time *tm)
 253 {
 254         return rs5c372_get_datetime(to_i2c_client(dev), tm);
 255 }
 256
 257 static int rs5c372_rtc_set_time(struct device *dev, struct rtc_time *tm)
 258 {
 259         return rs5c372_set_datetime(to_i2c_client(dev), tm);
 260 }
 261
 262 #if defined(CONFIG_RTC_INTF_DEV) || defined(CONFIG_RTC_INTF_DEV_MODULE)
 263
 264 static int
 265 rs5c_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
 266 {
 267         struct i2c_client       *client = to_i2c_client(dev);
 268         struct rs5c372          *rs5c = i2c_get_clientdata(client);
 269         unsigned char           buf[2];
 270         int                     status;
 271
 272         buf[1] = rs5c->regs[RS5C_REG_CTRL1];
 273         switch (cmd) {
 274         case RTC_UIE_OFF:
 275         case RTC_UIE_ON:
 276                 /* some 327a modes use a different IRQ pin for 1Hz irqs */
 277                 if (rs5c->type == rtc_rs5c372a
 278                                 && (buf[1] & RS5C372A_CTRL1_SL1))
 279                         return -ENOIOCTLCMD;
 280         case RTC_AIE_OFF:
 281         case RTC_AIE_ON:
 282                 /* these irq management calls only make sense for chips
 283                  * which are wired up to an IRQ.
 284                  */
 285                 if (!rs5c->has_irq)
 286                         return -ENOIOCTLCMD;
 287                 break;
 288         default:
 289                 return -ENOIOCTLCMD;
 290         }
 291
 292         status = rs5c_get_regs(rs5c);
 293         if (status < 0)
 294                 return status;
 295
 296         buf[0] = RS5C_ADDR(RS5C_REG_CTRL1);
 297         switch (cmd) {
 298         case RTC_AIE_OFF:       /* alarm off */
 299                 buf[1] &= ~RS5C_CTRL1_AALE;
 300                 break;
 301         case RTC_AIE_ON:        /* alarm on */
 302                 buf[1] |= RS5C_CTRL1_AALE;
 303                 break;
 304         case RTC_UIE_OFF:       /* update off */
 305                 buf[1] &= ~RS5C_CTRL1_CT_MASK;
 306                 break;
 307         case RTC_UIE_ON:        /* update on */
 308                 buf[1] &= ~RS5C_CTRL1_CT_MASK;
 309                 buf[1] |= RS5C_CTRL1_CT4;
 310                 break;
 311         }
 312         if ((i2c_master_send(client, buf, 2)) != 2) {
 313                 printk(KERN_WARNING "%s: can't update alarm\n",
 314                         rs5c->rtc->name);
 315                 status = -EIO;
 316         } else
 317                 rs5c->regs[RS5C_REG_CTRL1] = buf[1];
 318         return status;
 319 }
 320
 321 #else
 322 #define rs5c_rtc_ioctl  NULL
 323 #endif
 324
 325
 326 /* NOTE:  Since RTC_WKALM_{RD,SET} were originally defined for EFI,
 327  * which only exposes a polled programming interface; and since
 328  * these calls map directly to those EFI requests; we don't demand
 329  * we have an IRQ for this chip when we go through this API.
 330  *
 331  * The older x86_pc derived RTC_ALM_{READ,SET} calls require irqs
 332  * though, managed through RTC_AIE_{ON,OFF} requests.
 333  */
 334
 335 static int rs5c_read_alarm(struct device *dev, struct rtc_wkalrm *t)
 336 {
 337         struct i2c_client       *client = to_i2c_client(dev);
 338         struct rs5c372          *rs5c = i2c_get_clientdata(client);
 339         int                     status;
 340
 341         status = rs5c_get_regs(rs5c);
 342         if (status < 0)
 343                 return status;
 344
 345         /* report alarm time */
 346         t->time.tm_sec = 0;
 347         t->time.tm_min = BCD2BIN(rs5c->regs[RS5C_REG_ALARM_A_MIN] & 0x7f);
 348         t->time.tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C_REG_ALARM_A_HOURS]);
 349         t->time.tm_mday = -1;
 350         t->time.tm_mon = -1;
 351         t->time.tm_year = -1;
 352         t->time.tm_wday = -1;
 353         t->time.tm_yday = -1;
 354         t->time.tm_isdst = -1;
 355
 356         /* ... and status */
 357         t->enabled = !!(rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE);
 358         t->pending = !!(rs5c->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_AAFG);
 359
 360         return 0;
 361 }
 362
 363 static int rs5c_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 364 {
 365         struct i2c_client       *client = to_i2c_client(dev);
 366         struct rs5c372          *rs5c = i2c_get_clientdata(client);
 367         int                     status;
 368         unsigned char           buf[4];
 369
 370         /* only handle up to 24 hours in the future, like RTC_ALM_SET */
 371         if (t->time.tm_mday != -1
 372                         || t->time.tm_mon != -1
 373                         || t->time.tm_year != -1)
 374                 return -EINVAL;
 375
 376         /* REVISIT: round up tm_sec */
 377
 378         /* if needed, disable irq (clears pending status) */
 379         status = rs5c_get_regs(rs5c);
 380         if (status < 0)
 381                 return status;
 382         if (rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE) {
 383                 buf[0] = RS5C_ADDR(RS5C_REG_CTRL1);
 384                 buf[1] = rs5c->regs[RS5C_REG_CTRL1] & ~RS5C_CTRL1_AALE;
 385                 if (i2c_master_send(client, buf, 2) != 2) {
 386                         pr_debug("%s: can't disable alarm\n", rs5c->rtc->name);
 387                         return -EIO;
 388                 }
 389                 rs5c->regs[RS5C_REG_CTRL1] = buf[1];
 390         }
 391
 392         /* set alarm */
 393         buf[0] = RS5C_ADDR(RS5C_REG_ALARM_A_MIN);
 394         buf[1] = BIN2BCD(t->time.tm_min);
 395         buf[2] = rs5c_hr2reg(rs5c, t->time.tm_hour);
 396         buf[3] = 0x7f;  /* any/all days */
 397         if ((i2c_master_send(client, buf, 4)) != 4) {
 398                 pr_debug("%s: can't set alarm time\n", rs5c->rtc->name);
 399                 return -EIO;
 400         }
 401
 402         /* ... and maybe enable its irq */
 403         if (t->enabled) {
 404                 buf[0] = RS5C_ADDR(RS5C_REG_CTRL1);
 405                 buf[1] = rs5c->regs[RS5C_REG_CTRL1] | RS5C_CTRL1_AALE;
 406                 if ((i2c_master_send(client, buf, 2)) != 2)
 407                         printk(KERN_WARNING "%s: can't enable alarm\n",
 408                                 rs5c->rtc->name);
 409                 rs5c->regs[RS5C_REG_CTRL1] = buf[1];
 410         }
 411
 412         return 0;
 413 }
 414
 415 #if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
 416
 417 static int rs5c372_rtc_proc(struct device *dev, struct seq_file *seq)
 418 {
 419         int err, osc, trim;
 420
 421         err = rs5c372_get_trim(to_i2c_client(dev), &osc, &trim);
 422         if (err == 0) {
 423                 seq_printf(seq, "crystal\t\t: %d.%03d KHz\n",
 424                                 osc / 1000, osc % 1000);
 425                 seq_printf(seq, "trim\t\t: %d\n", trim);
 426         }
 427
 428         return 0;
 429 }
 430
 431 #else
 432 #define rs5c372_rtc_proc        NULL
 433 #endif
 434
 435 static const struct rtc_class_ops rs5c372_rtc_ops = {
 436         .proc           = rs5c372_rtc_proc,
 437         .ioctl          = rs5c_rtc_ioctl,
 438         .read_time      = rs5c372_rtc_read_time,
 439         .set_time       = rs5c372_rtc_set_time,
 440         .read_alarm     = rs5c_read_alarm,
 441         .set_alarm      = rs5c_set_alarm,
 442 };
 443
 444 #if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
 445
 446 static ssize_t rs5c372_sysfs_show_trim(struct device *dev,
 447                                 struct device_attribute *attr, char *buf)
 448 {
 449         int err, trim;
 450
 451         err = rs5c372_get_trim(to_i2c_client(dev), NULL, &trim);
 452         if (err)
 453                 return err;
 454
 455         return sprintf(buf, "%d\n", trim);
 456 }
 457 static DEVICE_ATTR(trim, S_IRUGO, rs5c372_sysfs_show_trim, NULL);
 458
 459 static ssize_t rs5c372_sysfs_show_osc(struct device *dev,
 460                                 struct device_attribute *attr, char *buf)
 461 {
 462         int err, osc;
 463
 464         err = rs5c372_get_trim(to_i2c_client(dev), &osc, NULL);
 465         if (err)
 466                 return err;
 467
 468         return sprintf(buf, "%d.%03d KHz\n", osc / 1000, osc % 1000);
 469 }
 470 static DEVICE_ATTR(osc, S_IRUGO, rs5c372_sysfs_show_osc, NULL);
 471
 472 static int rs5c_sysfs_register(struct device *dev)
 473 {
 474         int err;
 475
 476         err = device_create_file(dev, &dev_attr_trim);
 477         if (err)
 478                 return err;
 479         err = device_create_file(dev, &dev_attr_osc);
 480         if (err)
 481                 device_remove_file(dev, &dev_attr_trim);
 482
 483         return err;
 484 }
 485
 486 static void rs5c_sysfs_unregister(struct device *dev)
 487 {
 488         device_remove_file(dev, &dev_attr_trim);
 489         device_remove_file(dev, &dev_attr_osc);
 490 }
 491
 492 #else
 493 static int rs5c_sysfs_register(struct device *dev)
 494 {
 495         return 0;
 496 }
 497
 498 static void rs5c_sysfs_unregister(struct device *dev)
 499 {
 500         /* nothing */
 501 }
 502 #endif  /* SYSFS */
 503
 504 static struct i2c_driver rs5c372_driver;
 505
 506 static int rs5c372_probe(struct i2c_client *client,
 507                          const struct i2c_device_id *id)
 508 {
 509         int err = 0;
 510         struct rs5c372 *rs5c372;
 511         struct rtc_time tm;
 512
 513         dev_dbg(&client->dev, "%s\n", __func__);
 514
 515         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 516                 err = -ENODEV;
 517                 goto exit;
 518         }
 519
 520         if (!(rs5c372 = kzalloc(sizeof(struct rs5c372), GFP_KERNEL))) {
 521                 err = -ENOMEM;
 522                 goto exit;
 523         }
 524
 525         rs5c372->client = client;
 526         i2c_set_clientdata(client, rs5c372);
 527         rs5c372->type = id->driver_data;
 528
 529         /* we read registers 0x0f then 0x00-0x0f; skip the first one */
 530         rs5c372->regs = &rs5c372->buf[1];
 531
 532         err = rs5c_get_regs(rs5c372);
 533         if (err < 0)
 534                 goto exit_kfree;
 535
 536         /* clock may be set for am/pm or 24 hr time */
 537         switch (rs5c372->type) {
 538         case rtc_rs5c372a:
 539         case rtc_rs5c372b:
 540                 /* alarm uses ALARM_A; and nINTRA on 372a, nINTR on 372b.
 541                  * so does periodic irq, except some 327a modes.
 542                  */
 543                 if (rs5c372->regs[RS5C_REG_CTRL2] & RS5C372_CTRL2_24)
 544                         rs5c372->time24 = 1;
 545                 break;
 546         case rtc_rv5c386:
 547         case rtc_rv5c387a:
 548                 if (rs5c372->regs[RS5C_REG_CTRL1] & RV5C387_CTRL1_24)
 549                         rs5c372->time24 = 1;
 550                 /* alarm uses ALARM_W; and nINTRB for alarm and periodic
 551                  * irq, on both 386 and 387
 552                  */
 553                 break;
 554         default:
 555                 dev_err(&client->dev, "unknown RTC type\n");
 556                 goto exit_kfree;
 557         }
 558
 559         /* if the oscillator lost power and no other software (like
 560          * the bootloader) set it up, do it here.
 561          */
 562         if (rs5c372->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_XSTP) {
 563                 unsigned char buf[3];
 564
 565                 rs5c372->regs[RS5C_REG_CTRL2] &= ~RS5C_CTRL2_XSTP;
 566
 567                 buf[0] = RS5C_ADDR(RS5C_REG_CTRL1);
 568                 buf[1] = rs5c372->regs[RS5C_REG_CTRL1];
 569                 buf[2] = rs5c372->regs[RS5C_REG_CTRL2];
 570
 571                 /* use 24hr mode */
 572                 switch (rs5c372->type) {
 573                 case rtc_rs5c372a:
 574                 case rtc_rs5c372b:
 575                         buf[2] |= RS5C372_CTRL2_24;
 576                         rs5c372->time24 = 1;
 577                         break;
 578                 case rtc_rv5c386:
 579                 case rtc_rv5c387a:
 580                         buf[1] |= RV5C387_CTRL1_24;
 581                         rs5c372->time24 = 1;
 582                         break;
 583                 default:
 584                         /* impossible */
 585                         break;
 586                 }
 587
 588                 if ((i2c_master_send(client, buf, 3)) != 3) {
 589                         dev_err(&client->dev, "setup error\n");
 590                         goto exit_kfree;
 591                 }
 592                 rs5c372->regs[RS5C_REG_CTRL1] = buf[1];
 593                 rs5c372->regs[RS5C_REG_CTRL2] = buf[2];
 594         }
 595
 596         if (rs5c372_get_datetime(client, &tm) < 0)
 597                 dev_warn(&client->dev, "clock needs to be set\n");
 598
 599         dev_info(&client->dev, "%s found, %s, driver version " DRV_VERSION "\n",
 600                         ({ char *s; switch (rs5c372->type) {
 601                         case rtc_rs5c372a:      s = "rs5c372a"; break;
 602                         case rtc_rs5c372b:      s = "rs5c372b"; break;
 603                         case rtc_rv5c386:       s = "rv5c386"; break;
 604                         case rtc_rv5c387a:      s = "rv5c387a"; break;
 605                         default:                s = "chip"; break;
 606                         }; s;}),
 607                         rs5c372->time24 ? "24hr" : "am/pm"
 608                         );
 609
 610         /* REVISIT use client->irq to register alarm irq ... */
 611
 612         rs5c372->rtc = rtc_device_register(rs5c372_driver.driver.name,
 613                                 &client->dev, &rs5c372_rtc_ops, THIS_MODULE);
 614
 615         if (IS_ERR(rs5c372->rtc)) {
 616                 err = PTR_ERR(rs5c372->rtc);
 617                 goto exit_kfree;
 618         }
 619
 620         err = rs5c_sysfs_register(&client->dev);
 621         if (err)
 622                 goto exit_devreg;
 623
 624         return 0;
 625
 626 exit_devreg:
 627         rtc_device_unregister(rs5c372->rtc);
 628
 629 exit_kfree:
 630         kfree(rs5c372);
 631
 632 exit:
 633         return err;
 634 }
 635
 636 static int rs5c372_remove(struct i2c_client *client)
 637 {
 638         struct rs5c372 *rs5c372 = i2c_get_clientdata(client);
 639
 640         rtc_device_unregister(rs5c372->rtc);
 641         rs5c_sysfs_unregister(&client->dev);
 642         kfree(rs5c372);
 643         return 0;
 644 }
 645
 646 static struct i2c_driver rs5c372_driver = {
 647         .driver         = {
 648                 .name   = "rtc-rs5c372",
 649         },
 650         .probe          = rs5c372_probe,
 651         .remove         = rs5c372_remove,
 652         .id_table       = rs5c372_id,
 653 };
 654
 655 static __init int rs5c372_init(void)
 656 {
 657         return i2c_add_driver(&rs5c372_driver);
 658 }
 659
 660 static __exit void rs5c372_exit(void)
 661 {
 662         i2c_del_driver(&rs5c372_driver);
 663 }
 664
 665 module_init(rs5c372_init);
 666 module_exit(rs5c372_exit);
 667
 668 MODULE_AUTHOR(
 669                 "Pavel Mironchik <pmironchik@optifacio.net>, "
 670                 "Alessandro Zummo <a.zummo@towertech.it>");
 671 MODULE_DESCRIPTION("Ricoh RS5C372 RTC driver");
 672 MODULE_LICENSE("GPL");
 673 MODULE_VERSION(DRV_VERSION);