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