GNU Linux-libre 4.4.289-gnu1
[releases.git] / drivers / rtc / rtc-rs5c372.c
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
68 enum rtc_type {
69         rtc_undef = 0,
70         rtc_r2025sd,
71         rtc_r2221tl,
72         rtc_rs5c372a,
73         rtc_rs5c372b,
74         rtc_rv5c386,
75         rtc_rv5c387a,
76 };
77
78 static const struct i2c_device_id rs5c372_id[] = {
79         { "r2025sd", rtc_r2025sd },
80         { "r2221tl", rtc_r2221tl },
81         { "rs5c372a", rtc_rs5c372a },
82         { "rs5c372b", rtc_rs5c372b },
83         { "rv5c386", rtc_rv5c386 },
84         { "rv5c387a", rtc_rv5c387a },
85         { }
86 };
87 MODULE_DEVICE_TABLE(i2c, rs5c372_id);
88
89 /* REVISIT:  this assumes that:
90  *  - we're in the 21st century, so it's safe to ignore the century
91  *    bit for rv5c38[67] (REG_MONTH bit 7);
92  *  - we should use ALARM_A not ALARM_B (may be wrong on some boards)
93  */
94 struct rs5c372 {
95         struct i2c_client       *client;
96         struct rtc_device       *rtc;
97         enum rtc_type           type;
98         unsigned                time24:1;
99         unsigned                has_irq:1;
100         unsigned                smbus:1;
101         char                    buf[17];
102         char                    *regs;
103 };
104
105 static int rs5c_get_regs(struct rs5c372 *rs5c)
106 {
107         struct i2c_client       *client = rs5c->client;
108         struct i2c_msg          msgs[] = {
109                 {
110                         .addr = client->addr,
111                         .flags = I2C_M_RD,
112                         .len = sizeof(rs5c->buf),
113                         .buf = rs5c->buf
114                 },
115         };
116
117         /* This implements the third reading method from the datasheet, using
118          * an internal address that's reset after each transaction (by STOP)
119          * to 0x0f ... so we read extra registers, and skip the first one.
120          *
121          * The first method doesn't work with the iop3xx adapter driver, on at
122          * least 80219 chips; this works around that bug.
123          *
124          * The third method on the other hand doesn't work for the SMBus-only
125          * configurations, so we use the the first method there, stripping off
126          * the extra register in the process.
127          */
128         if (rs5c->smbus) {
129                 int addr = RS5C_ADDR(RS5C372_REG_SECS);
130                 int size = sizeof(rs5c->buf) - 1;
131
132                 if (i2c_smbus_read_i2c_block_data(client, addr, size,
133                                                   rs5c->buf + 1) != size) {
134                         dev_warn(&client->dev, "can't read registers\n");
135                         return -EIO;
136                 }
137         } else {
138                 if ((i2c_transfer(client->adapter, msgs, 1)) != 1) {
139                         dev_warn(&client->dev, "can't read registers\n");
140                         return -EIO;
141                 }
142         }
143
144         dev_dbg(&client->dev,
145                 "%3ph (%02x) %3ph (%02x), %3ph, %3ph; %02x %02x\n",
146                 rs5c->regs + 0, rs5c->regs[3],
147                 rs5c->regs + 4, rs5c->regs[7],
148                 rs5c->regs + 8, rs5c->regs + 11,
149                 rs5c->regs[14], rs5c->regs[15]);
150
151         return 0;
152 }
153
154 static unsigned rs5c_reg2hr(struct rs5c372 *rs5c, unsigned reg)
155 {
156         unsigned        hour;
157
158         if (rs5c->time24)
159                 return bcd2bin(reg & 0x3f);
160
161         hour = bcd2bin(reg & 0x1f);
162         if (hour == 12)
163                 hour = 0;
164         if (reg & 0x20)
165                 hour += 12;
166         return hour;
167 }
168
169 static unsigned rs5c_hr2reg(struct rs5c372 *rs5c, unsigned hour)
170 {
171         if (rs5c->time24)
172                 return bin2bcd(hour);
173
174         if (hour > 12)
175                 return 0x20 | bin2bcd(hour - 12);
176         if (hour == 12)
177                 return 0x20 | bin2bcd(12);
178         if (hour == 0)
179                 return bin2bcd(12);
180         return bin2bcd(hour);
181 }
182
183 static int rs5c372_get_datetime(struct i2c_client *client, struct rtc_time *tm)
184 {
185         struct rs5c372  *rs5c = i2c_get_clientdata(client);
186         int             status = rs5c_get_regs(rs5c);
187
188         if (status < 0)
189                 return status;
190
191         tm->tm_sec = bcd2bin(rs5c->regs[RS5C372_REG_SECS] & 0x7f);
192         tm->tm_min = bcd2bin(rs5c->regs[RS5C372_REG_MINS] & 0x7f);
193         tm->tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C372_REG_HOURS]);
194
195         tm->tm_wday = bcd2bin(rs5c->regs[RS5C372_REG_WDAY] & 0x07);
196         tm->tm_mday = bcd2bin(rs5c->regs[RS5C372_REG_DAY] & 0x3f);
197
198         /* tm->tm_mon is zero-based */
199         tm->tm_mon = bcd2bin(rs5c->regs[RS5C372_REG_MONTH] & 0x1f) - 1;
200
201         /* year is 1900 + tm->tm_year */
202         tm->tm_year = bcd2bin(rs5c->regs[RS5C372_REG_YEAR]) + 100;
203
204         dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
205                 "mday=%d, mon=%d, year=%d, wday=%d\n",
206                 __func__,
207                 tm->tm_sec, tm->tm_min, tm->tm_hour,
208                 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
209
210         /* rtc might need initialization */
211         return rtc_valid_tm(tm);
212 }
213
214 static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm)
215 {
216         struct rs5c372  *rs5c = i2c_get_clientdata(client);
217         unsigned char   buf[7];
218         int             addr;
219
220         dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d "
221                 "mday=%d, mon=%d, year=%d, wday=%d\n",
222                 __func__,
223                 tm->tm_sec, tm->tm_min, tm->tm_hour,
224                 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
225
226         addr   = RS5C_ADDR(RS5C372_REG_SECS);
227         buf[0] = bin2bcd(tm->tm_sec);
228         buf[1] = bin2bcd(tm->tm_min);
229         buf[2] = rs5c_hr2reg(rs5c, tm->tm_hour);
230         buf[3] = bin2bcd(tm->tm_wday);
231         buf[4] = bin2bcd(tm->tm_mday);
232         buf[5] = bin2bcd(tm->tm_mon + 1);
233         buf[6] = bin2bcd(tm->tm_year - 100);
234
235         if (i2c_smbus_write_i2c_block_data(client, addr, sizeof(buf), buf) < 0) {
236                 dev_err(&client->dev, "%s: write error\n", __func__);
237                 return -EIO;
238         }
239
240         return 0;
241 }
242
243 #if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
244 #define NEED_TRIM
245 #endif
246
247 #if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
248 #define NEED_TRIM
249 #endif
250
251 #ifdef  NEED_TRIM
252 static int rs5c372_get_trim(struct i2c_client *client, int *osc, int *trim)
253 {
254         struct rs5c372 *rs5c372 = i2c_get_clientdata(client);
255         u8 tmp = rs5c372->regs[RS5C372_REG_TRIM];
256
257         if (osc)
258                 *osc = (tmp & RS5C372_TRIM_XSL) ? 32000 : 32768;
259
260         if (trim) {
261                 dev_dbg(&client->dev, "%s: raw trim=%x\n", __func__, tmp);
262                 tmp &= RS5C372_TRIM_MASK;
263                 if (tmp & 0x3e) {
264                         int t = tmp & 0x3f;
265
266                         if (tmp & 0x40)
267                                 t = (~t | (s8)0xc0) + 1;
268                         else
269                                 t = t - 1;
270
271                         tmp = t * 2;
272                 } else
273                         tmp = 0;
274                 *trim = tmp;
275         }
276
277         return 0;
278 }
279 #endif
280
281 static int rs5c372_rtc_read_time(struct device *dev, struct rtc_time *tm)
282 {
283         return rs5c372_get_datetime(to_i2c_client(dev), tm);
284 }
285
286 static int rs5c372_rtc_set_time(struct device *dev, struct rtc_time *tm)
287 {
288         return rs5c372_set_datetime(to_i2c_client(dev), tm);
289 }
290
291
292 static int rs5c_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
293 {
294         struct i2c_client       *client = to_i2c_client(dev);
295         struct rs5c372          *rs5c = i2c_get_clientdata(client);
296         unsigned char           buf;
297         int                     status, addr;
298
299         buf = rs5c->regs[RS5C_REG_CTRL1];
300
301         if (!rs5c->has_irq)
302                 return -EINVAL;
303
304         status = rs5c_get_regs(rs5c);
305         if (status < 0)
306                 return status;
307
308         addr = RS5C_ADDR(RS5C_REG_CTRL1);
309         if (enabled)
310                 buf |= RS5C_CTRL1_AALE;
311         else
312                 buf &= ~RS5C_CTRL1_AALE;
313
314         if (i2c_smbus_write_byte_data(client, addr, buf) < 0) {
315                 dev_warn(dev, "can't update alarm\n");
316                 status = -EIO;
317         } else
318                 rs5c->regs[RS5C_REG_CTRL1] = buf;
319
320         return status;
321 }
322
323
324 /* NOTE:  Since RTC_WKALM_{RD,SET} were originally defined for EFI,
325  * which only exposes a polled programming interface; and since
326  * these calls map directly to those EFI requests; we don't demand
327  * we have an IRQ for this chip when we go through this API.
328  *
329  * The older x86_pc derived RTC_ALM_{READ,SET} calls require irqs
330  * though, managed through RTC_AIE_{ON,OFF} requests.
331  */
332
333 static int rs5c_read_alarm(struct device *dev, struct rtc_wkalrm *t)
334 {
335         struct i2c_client       *client = to_i2c_client(dev);
336         struct rs5c372          *rs5c = i2c_get_clientdata(client);
337         int                     status;
338
339         status = rs5c_get_regs(rs5c);
340         if (status < 0)
341                 return status;
342
343         /* report alarm time */
344         t->time.tm_sec = 0;
345         t->time.tm_min = bcd2bin(rs5c->regs[RS5C_REG_ALARM_A_MIN] & 0x7f);
346         t->time.tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C_REG_ALARM_A_HOURS]);
347         t->time.tm_mday = -1;
348         t->time.tm_mon = -1;
349         t->time.tm_year = -1;
350         t->time.tm_wday = -1;
351         t->time.tm_yday = -1;
352         t->time.tm_isdst = -1;
353
354         /* ... and status */
355         t->enabled = !!(rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE);
356         t->pending = !!(rs5c->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_AAFG);
357
358         return 0;
359 }
360
361 static int rs5c_set_alarm(struct device *dev, struct rtc_wkalrm *t)
362 {
363         struct i2c_client       *client = to_i2c_client(dev);
364         struct rs5c372          *rs5c = i2c_get_clientdata(client);
365         int                     status, addr, i;
366         unsigned char           buf[3];
367
368         /* only handle up to 24 hours in the future, like RTC_ALM_SET */
369         if (t->time.tm_mday != -1
370                         || t->time.tm_mon != -1
371                         || t->time.tm_year != -1)
372                 return -EINVAL;
373
374         /* REVISIT: round up tm_sec */
375
376         /* if needed, disable irq (clears pending status) */
377         status = rs5c_get_regs(rs5c);
378         if (status < 0)
379                 return status;
380         if (rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE) {
381                 addr = RS5C_ADDR(RS5C_REG_CTRL1);
382                 buf[0] = rs5c->regs[RS5C_REG_CTRL1] & ~RS5C_CTRL1_AALE;
383                 if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0) {
384                         dev_dbg(dev, "can't disable alarm\n");
385                         return -EIO;
386                 }
387                 rs5c->regs[RS5C_REG_CTRL1] = buf[0];
388         }
389
390         /* set alarm */
391         buf[0] = bin2bcd(t->time.tm_min);
392         buf[1] = rs5c_hr2reg(rs5c, t->time.tm_hour);
393         buf[2] = 0x7f;  /* any/all days */
394
395         for (i = 0; i < sizeof(buf); i++) {
396                 addr = RS5C_ADDR(RS5C_REG_ALARM_A_MIN + i);
397                 if (i2c_smbus_write_byte_data(client, addr, buf[i]) < 0) {
398                         dev_dbg(dev, "can't set alarm time\n");
399                         return -EIO;
400                 }
401         }
402
403         /* ... and maybe enable its irq */
404         if (t->enabled) {
405                 addr = RS5C_ADDR(RS5C_REG_CTRL1);
406                 buf[0] = rs5c->regs[RS5C_REG_CTRL1] | RS5C_CTRL1_AALE;
407                 if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0)
408                         dev_warn(dev, "can't enable alarm\n");
409                 rs5c->regs[RS5C_REG_CTRL1] = buf[0];
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         .read_time      = rs5c372_rtc_read_time,
438         .set_time       = rs5c372_rtc_set_time,
439         .read_alarm     = rs5c_read_alarm,
440         .set_alarm      = rs5c_set_alarm,
441         .alarm_irq_enable = rs5c_rtc_alarm_irq_enable,
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 rs5c_oscillator_setup(struct rs5c372 *rs5c372)
507 {
508         unsigned char buf[2];
509         int addr, i, ret = 0;
510
511         if (rs5c372->type == rtc_r2025sd) {
512                 if (!(rs5c372->regs[RS5C_REG_CTRL2] & R2025_CTRL2_XST))
513                         return ret;
514                 rs5c372->regs[RS5C_REG_CTRL2] &= ~R2025_CTRL2_XST;
515         } else {
516                 if (!(rs5c372->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_XSTP))
517                         return ret;
518                 rs5c372->regs[RS5C_REG_CTRL2] &= ~RS5C_CTRL2_XSTP;
519         }
520
521         addr   = RS5C_ADDR(RS5C_REG_CTRL1);
522         buf[0] = rs5c372->regs[RS5C_REG_CTRL1];
523         buf[1] = rs5c372->regs[RS5C_REG_CTRL2];
524
525         /* use 24hr mode */
526         switch (rs5c372->type) {
527         case rtc_rs5c372a:
528         case rtc_rs5c372b:
529                 buf[1] |= RS5C372_CTRL2_24;
530                 rs5c372->time24 = 1;
531                 break;
532         case rtc_r2025sd:
533         case rtc_r2221tl:
534         case rtc_rv5c386:
535         case rtc_rv5c387a:
536                 buf[0] |= RV5C387_CTRL1_24;
537                 rs5c372->time24 = 1;
538                 break;
539         default:
540                 /* impossible */
541                 break;
542         }
543
544         for (i = 0; i < sizeof(buf); i++) {
545                 addr = RS5C_ADDR(RS5C_REG_CTRL1 + i);
546                 ret = i2c_smbus_write_byte_data(rs5c372->client, addr, buf[i]);
547                 if (unlikely(ret < 0))
548                         return ret;
549         }
550
551         rs5c372->regs[RS5C_REG_CTRL1] = buf[0];
552         rs5c372->regs[RS5C_REG_CTRL2] = buf[1];
553
554         return 0;
555 }
556
557 static int rs5c372_probe(struct i2c_client *client,
558                          const struct i2c_device_id *id)
559 {
560         int err = 0;
561         int smbus_mode = 0;
562         struct rs5c372 *rs5c372;
563         struct rtc_time tm;
564
565         dev_dbg(&client->dev, "%s\n", __func__);
566
567         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
568                         I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK)) {
569                 /*
570                  * If we don't have any master mode adapter, try breaking
571                  * it down in to the barest of capabilities.
572                  */
573                 if (i2c_check_functionality(client->adapter,
574                                 I2C_FUNC_SMBUS_BYTE_DATA |
575                                 I2C_FUNC_SMBUS_I2C_BLOCK))
576                         smbus_mode = 1;
577                 else {
578                         /* Still no good, give up */
579                         err = -ENODEV;
580                         goto exit;
581                 }
582         }
583
584         rs5c372 = devm_kzalloc(&client->dev, sizeof(struct rs5c372),
585                                 GFP_KERNEL);
586         if (!rs5c372) {
587                 err = -ENOMEM;
588                 goto exit;
589         }
590
591         rs5c372->client = client;
592         i2c_set_clientdata(client, rs5c372);
593         rs5c372->type = id->driver_data;
594
595         /* we read registers 0x0f then 0x00-0x0f; skip the first one */
596         rs5c372->regs = &rs5c372->buf[1];
597         rs5c372->smbus = smbus_mode;
598
599         err = rs5c_get_regs(rs5c372);
600         if (err < 0)
601                 goto exit;
602
603         /* clock may be set for am/pm or 24 hr time */
604         switch (rs5c372->type) {
605         case rtc_rs5c372a:
606         case rtc_rs5c372b:
607                 /* alarm uses ALARM_A; and nINTRA on 372a, nINTR on 372b.
608                  * so does periodic irq, except some 327a modes.
609                  */
610                 if (rs5c372->regs[RS5C_REG_CTRL2] & RS5C372_CTRL2_24)
611                         rs5c372->time24 = 1;
612                 break;
613         case rtc_r2025sd:
614         case rtc_r2221tl:
615         case rtc_rv5c386:
616         case rtc_rv5c387a:
617                 if (rs5c372->regs[RS5C_REG_CTRL1] & RV5C387_CTRL1_24)
618                         rs5c372->time24 = 1;
619                 /* alarm uses ALARM_W; and nINTRB for alarm and periodic
620                  * irq, on both 386 and 387
621                  */
622                 break;
623         default:
624                 dev_err(&client->dev, "unknown RTC type\n");
625                 goto exit;
626         }
627
628         /* if the oscillator lost power and no other software (like
629          * the bootloader) set it up, do it here.
630          *
631          * The R2025S/D does this a little differently than the other
632          * parts, so we special case that..
633          */
634         err = rs5c_oscillator_setup(rs5c372);
635         if (unlikely(err < 0)) {
636                 dev_err(&client->dev, "setup error\n");
637                 goto exit;
638         }
639
640         if (rs5c372_get_datetime(client, &tm) < 0)
641                 dev_warn(&client->dev, "clock needs to be set\n");
642
643         dev_info(&client->dev, "%s found, %s, driver version " DRV_VERSION "\n",
644                         ({ char *s; switch (rs5c372->type) {
645                         case rtc_r2025sd:       s = "r2025sd"; break;
646                         case rtc_r2221tl:       s = "r2221tl"; break;
647                         case rtc_rs5c372a:      s = "rs5c372a"; break;
648                         case rtc_rs5c372b:      s = "rs5c372b"; break;
649                         case rtc_rv5c386:       s = "rv5c386"; break;
650                         case rtc_rv5c387a:      s = "rv5c387a"; break;
651                         default:                s = "chip"; break;
652                         }; s;}),
653                         rs5c372->time24 ? "24hr" : "am/pm"
654                         );
655
656         /* REVISIT use client->irq to register alarm irq ... */
657         rs5c372->rtc = devm_rtc_device_register(&client->dev,
658                                         rs5c372_driver.driver.name,
659                                         &rs5c372_rtc_ops, THIS_MODULE);
660
661         if (IS_ERR(rs5c372->rtc)) {
662                 err = PTR_ERR(rs5c372->rtc);
663                 goto exit;
664         }
665
666         err = rs5c_sysfs_register(&client->dev);
667         if (err)
668                 goto exit;
669
670         return 0;
671
672 exit:
673         return err;
674 }
675
676 static int rs5c372_remove(struct i2c_client *client)
677 {
678         rs5c_sysfs_unregister(&client->dev);
679         return 0;
680 }
681
682 static struct i2c_driver rs5c372_driver = {
683         .driver         = {
684                 .name   = "rtc-rs5c372",
685         },
686         .probe          = rs5c372_probe,
687         .remove         = rs5c372_remove,
688         .id_table       = rs5c372_id,
689 };
690
691 module_i2c_driver(rs5c372_driver);
692
693 MODULE_AUTHOR(
694                 "Pavel Mironchik <pmironchik@optifacio.net>, "
695                 "Alessandro Zummo <a.zummo@towertech.it>, "
696                 "Paul Mundt <lethal@linux-sh.org>");
697 MODULE_DESCRIPTION("Ricoh RS5C372 RTC driver");
698 MODULE_LICENSE("GPL");
699 MODULE_VERSION(DRV_VERSION);