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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_r2221tl,
72 rtc_rs5c372a,
73 rtc_rs5c372b,
74 rtc_rv5c386,
75 rtc_rv5c387a,
76};
77
78static 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};
87MODULE_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 */
94struct 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
105static 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
154static 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
169static 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
183static 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
214static 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
252static 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
281static 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
286static 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
292static 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
333static 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
361static 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
417static 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
435static 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
446static 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}
457static DEVICE_ATTR(trim, S_IRUGO, rs5c372_sysfs_show_trim, NULL);
458
459static 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}
470static DEVICE_ATTR(osc, S_IRUGO, rs5c372_sysfs_show_osc, NULL);
471
472static 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
486static 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
493static int rs5c_sysfs_register(struct device *dev)
494{
495 return 0;
496}
497
498static void rs5c_sysfs_unregister(struct device *dev)
499{
500 /* nothing */
501}
502#endif /* SYSFS */
503
504static struct i2c_driver rs5c372_driver;
505
506static 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
557static 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
672exit:
673 return err;
674}
675
676static int rs5c372_remove(struct i2c_client *client)
677{
678 rs5c_sysfs_unregister(&client->dev);
679 return 0;
680}
681
682static 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
691module_i2c_driver(rs5c372_driver);
692
693MODULE_AUTHOR(
694 "Pavel Mironchik <pmironchik@optifacio.net>, "
695 "Alessandro Zummo <a.zummo@towertech.it>, "
696 "Paul Mundt <lethal@linux-sh.org>");
697MODULE_DESCRIPTION("Ricoh RS5C372 RTC driver");
698MODULE_LICENSE("GPL");
699MODULE_VERSION(DRV_VERSION);
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/*
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 R2025_CTRL2_XST (1 << 5)
55# define RS5C_CTRL2_XSTP (1 << 4) /* only if !R2025S/D */
56# define RS5C_CTRL2_CTFG (1 << 2)
57# define RS5C_CTRL2_AAFG (1 << 1) /* or WAFG */
58# define RS5C_CTRL2_BAFG (1 << 0) /* or DAFG */
59
60
61/* to read (style 1) or write registers starting at R */
62#define RS5C_ADDR(R) (((R) << 4) | 0)
63
64
65enum rtc_type {
66 rtc_undef = 0,
67 rtc_r2025sd,
68 rtc_r2221tl,
69 rtc_rs5c372a,
70 rtc_rs5c372b,
71 rtc_rv5c386,
72 rtc_rv5c387a,
73};
74
75static const struct i2c_device_id rs5c372_id[] = {
76 { "r2025sd", rtc_r2025sd },
77 { "r2221tl", rtc_r2221tl },
78 { "rs5c372a", rtc_rs5c372a },
79 { "rs5c372b", rtc_rs5c372b },
80 { "rv5c386", rtc_rv5c386 },
81 { "rv5c387a", rtc_rv5c387a },
82 { }
83};
84MODULE_DEVICE_TABLE(i2c, rs5c372_id);
85
86/* REVISIT: this assumes that:
87 * - we're in the 21st century, so it's safe to ignore the century
88 * bit for rv5c38[67] (REG_MONTH bit 7);
89 * - we should use ALARM_A not ALARM_B (may be wrong on some boards)
90 */
91struct rs5c372 {
92 struct i2c_client *client;
93 struct rtc_device *rtc;
94 enum rtc_type type;
95 unsigned time24:1;
96 unsigned has_irq:1;
97 unsigned smbus:1;
98 char buf[17];
99 char *regs;
100};
101
102static int rs5c_get_regs(struct rs5c372 *rs5c)
103{
104 struct i2c_client *client = rs5c->client;
105 struct i2c_msg msgs[] = {
106 {
107 .addr = client->addr,
108 .flags = I2C_M_RD,
109 .len = sizeof(rs5c->buf),
110 .buf = rs5c->buf
111 },
112 };
113
114 /* This implements the third reading method from the datasheet, using
115 * an internal address that's reset after each transaction (by STOP)
116 * to 0x0f ... so we read extra registers, and skip the first one.
117 *
118 * The first method doesn't work with the iop3xx adapter driver, on at
119 * least 80219 chips; this works around that bug.
120 *
121 * The third method on the other hand doesn't work for the SMBus-only
122 * configurations, so we use the the first method there, stripping off
123 * the extra register in the process.
124 */
125 if (rs5c->smbus) {
126 int addr = RS5C_ADDR(RS5C372_REG_SECS);
127 int size = sizeof(rs5c->buf) - 1;
128
129 if (i2c_smbus_read_i2c_block_data(client, addr, size,
130 rs5c->buf + 1) != size) {
131 dev_warn(&client->dev, "can't read registers\n");
132 return -EIO;
133 }
134 } else {
135 if ((i2c_transfer(client->adapter, msgs, 1)) != 1) {
136 dev_warn(&client->dev, "can't read registers\n");
137 return -EIO;
138 }
139 }
140
141 dev_dbg(&client->dev,
142 "%3ph (%02x) %3ph (%02x), %3ph, %3ph; %02x %02x\n",
143 rs5c->regs + 0, rs5c->regs[3],
144 rs5c->regs + 4, rs5c->regs[7],
145 rs5c->regs + 8, rs5c->regs + 11,
146 rs5c->regs[14], rs5c->regs[15]);
147
148 return 0;
149}
150
151static unsigned rs5c_reg2hr(struct rs5c372 *rs5c, unsigned reg)
152{
153 unsigned hour;
154
155 if (rs5c->time24)
156 return bcd2bin(reg & 0x3f);
157
158 hour = bcd2bin(reg & 0x1f);
159 if (hour == 12)
160 hour = 0;
161 if (reg & 0x20)
162 hour += 12;
163 return hour;
164}
165
166static unsigned rs5c_hr2reg(struct rs5c372 *rs5c, unsigned hour)
167{
168 if (rs5c->time24)
169 return bin2bcd(hour);
170
171 if (hour > 12)
172 return 0x20 | bin2bcd(hour - 12);
173 if (hour == 12)
174 return 0x20 | bin2bcd(12);
175 if (hour == 0)
176 return bin2bcd(12);
177 return bin2bcd(hour);
178}
179
180static int rs5c372_get_datetime(struct i2c_client *client, struct rtc_time *tm)
181{
182 struct rs5c372 *rs5c = i2c_get_clientdata(client);
183 int status = rs5c_get_regs(rs5c);
184
185 if (status < 0)
186 return status;
187
188 tm->tm_sec = bcd2bin(rs5c->regs[RS5C372_REG_SECS] & 0x7f);
189 tm->tm_min = bcd2bin(rs5c->regs[RS5C372_REG_MINS] & 0x7f);
190 tm->tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C372_REG_HOURS]);
191
192 tm->tm_wday = bcd2bin(rs5c->regs[RS5C372_REG_WDAY] & 0x07);
193 tm->tm_mday = bcd2bin(rs5c->regs[RS5C372_REG_DAY] & 0x3f);
194
195 /* tm->tm_mon is zero-based */
196 tm->tm_mon = bcd2bin(rs5c->regs[RS5C372_REG_MONTH] & 0x1f) - 1;
197
198 /* year is 1900 + tm->tm_year */
199 tm->tm_year = bcd2bin(rs5c->regs[RS5C372_REG_YEAR]) + 100;
200
201 dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
202 "mday=%d, mon=%d, year=%d, wday=%d\n",
203 __func__,
204 tm->tm_sec, tm->tm_min, tm->tm_hour,
205 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
206
207 /* rtc might need initialization */
208 return rtc_valid_tm(tm);
209}
210
211static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm)
212{
213 struct rs5c372 *rs5c = i2c_get_clientdata(client);
214 unsigned char buf[7];
215 int addr;
216
217 dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d "
218 "mday=%d, mon=%d, year=%d, wday=%d\n",
219 __func__,
220 tm->tm_sec, tm->tm_min, tm->tm_hour,
221 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
222
223 addr = RS5C_ADDR(RS5C372_REG_SECS);
224 buf[0] = bin2bcd(tm->tm_sec);
225 buf[1] = bin2bcd(tm->tm_min);
226 buf[2] = rs5c_hr2reg(rs5c, tm->tm_hour);
227 buf[3] = bin2bcd(tm->tm_wday);
228 buf[4] = bin2bcd(tm->tm_mday);
229 buf[5] = bin2bcd(tm->tm_mon + 1);
230 buf[6] = bin2bcd(tm->tm_year - 100);
231
232 if (i2c_smbus_write_i2c_block_data(client, addr, sizeof(buf), buf) < 0) {
233 dev_err(&client->dev, "%s: write error\n", __func__);
234 return -EIO;
235 }
236
237 return 0;
238}
239
240#if IS_ENABLED(CONFIG_RTC_INTF_PROC)
241#define NEED_TRIM
242#endif
243
244#if IS_ENABLED(CONFIG_RTC_INTF_SYSFS)
245#define NEED_TRIM
246#endif
247
248#ifdef NEED_TRIM
249static int rs5c372_get_trim(struct i2c_client *client, int *osc, int *trim)
250{
251 struct rs5c372 *rs5c372 = i2c_get_clientdata(client);
252 u8 tmp = rs5c372->regs[RS5C372_REG_TRIM];
253
254 if (osc)
255 *osc = (tmp & RS5C372_TRIM_XSL) ? 32000 : 32768;
256
257 if (trim) {
258 dev_dbg(&client->dev, "%s: raw trim=%x\n", __func__, tmp);
259 tmp &= RS5C372_TRIM_MASK;
260 if (tmp & 0x3e) {
261 int t = tmp & 0x3f;
262
263 if (tmp & 0x40)
264 t = (~t | (s8)0xc0) + 1;
265 else
266 t = t - 1;
267
268 tmp = t * 2;
269 } else
270 tmp = 0;
271 *trim = tmp;
272 }
273
274 return 0;
275}
276#endif
277
278static int rs5c372_rtc_read_time(struct device *dev, struct rtc_time *tm)
279{
280 return rs5c372_get_datetime(to_i2c_client(dev), tm);
281}
282
283static int rs5c372_rtc_set_time(struct device *dev, struct rtc_time *tm)
284{
285 return rs5c372_set_datetime(to_i2c_client(dev), tm);
286}
287
288
289static int rs5c_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
290{
291 struct i2c_client *client = to_i2c_client(dev);
292 struct rs5c372 *rs5c = i2c_get_clientdata(client);
293 unsigned char buf;
294 int status, addr;
295
296 buf = rs5c->regs[RS5C_REG_CTRL1];
297
298 if (!rs5c->has_irq)
299 return -EINVAL;
300
301 status = rs5c_get_regs(rs5c);
302 if (status < 0)
303 return status;
304
305 addr = RS5C_ADDR(RS5C_REG_CTRL1);
306 if (enabled)
307 buf |= RS5C_CTRL1_AALE;
308 else
309 buf &= ~RS5C_CTRL1_AALE;
310
311 if (i2c_smbus_write_byte_data(client, addr, buf) < 0) {
312 dev_warn(dev, "can't update alarm\n");
313 status = -EIO;
314 } else
315 rs5c->regs[RS5C_REG_CTRL1] = buf;
316
317 return status;
318}
319
320
321/* NOTE: Since RTC_WKALM_{RD,SET} were originally defined for EFI,
322 * which only exposes a polled programming interface; and since
323 * these calls map directly to those EFI requests; we don't demand
324 * we have an IRQ for this chip when we go through this API.
325 *
326 * The older x86_pc derived RTC_ALM_{READ,SET} calls require irqs
327 * though, managed through RTC_AIE_{ON,OFF} requests.
328 */
329
330static int rs5c_read_alarm(struct device *dev, struct rtc_wkalrm *t)
331{
332 struct i2c_client *client = to_i2c_client(dev);
333 struct rs5c372 *rs5c = i2c_get_clientdata(client);
334 int status;
335
336 status = rs5c_get_regs(rs5c);
337 if (status < 0)
338 return status;
339
340 /* report alarm time */
341 t->time.tm_sec = 0;
342 t->time.tm_min = bcd2bin(rs5c->regs[RS5C_REG_ALARM_A_MIN] & 0x7f);
343 t->time.tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C_REG_ALARM_A_HOURS]);
344
345 /* ... and status */
346 t->enabled = !!(rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE);
347 t->pending = !!(rs5c->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_AAFG);
348
349 return 0;
350}
351
352static int rs5c_set_alarm(struct device *dev, struct rtc_wkalrm *t)
353{
354 struct i2c_client *client = to_i2c_client(dev);
355 struct rs5c372 *rs5c = i2c_get_clientdata(client);
356 int status, addr, i;
357 unsigned char buf[3];
358
359 /* only handle up to 24 hours in the future, like RTC_ALM_SET */
360 if (t->time.tm_mday != -1
361 || t->time.tm_mon != -1
362 || t->time.tm_year != -1)
363 return -EINVAL;
364
365 /* REVISIT: round up tm_sec */
366
367 /* if needed, disable irq (clears pending status) */
368 status = rs5c_get_regs(rs5c);
369 if (status < 0)
370 return status;
371 if (rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE) {
372 addr = RS5C_ADDR(RS5C_REG_CTRL1);
373 buf[0] = rs5c->regs[RS5C_REG_CTRL1] & ~RS5C_CTRL1_AALE;
374 if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0) {
375 dev_dbg(dev, "can't disable alarm\n");
376 return -EIO;
377 }
378 rs5c->regs[RS5C_REG_CTRL1] = buf[0];
379 }
380
381 /* set alarm */
382 buf[0] = bin2bcd(t->time.tm_min);
383 buf[1] = rs5c_hr2reg(rs5c, t->time.tm_hour);
384 buf[2] = 0x7f; /* any/all days */
385
386 for (i = 0; i < sizeof(buf); i++) {
387 addr = RS5C_ADDR(RS5C_REG_ALARM_A_MIN + i);
388 if (i2c_smbus_write_byte_data(client, addr, buf[i]) < 0) {
389 dev_dbg(dev, "can't set alarm time\n");
390 return -EIO;
391 }
392 }
393
394 /* ... and maybe enable its irq */
395 if (t->enabled) {
396 addr = RS5C_ADDR(RS5C_REG_CTRL1);
397 buf[0] = rs5c->regs[RS5C_REG_CTRL1] | RS5C_CTRL1_AALE;
398 if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0)
399 dev_warn(dev, "can't enable alarm\n");
400 rs5c->regs[RS5C_REG_CTRL1] = buf[0];
401 }
402
403 return 0;
404}
405
406#if IS_ENABLED(CONFIG_RTC_INTF_PROC)
407
408static 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
426static const struct rtc_class_ops rs5c372_rtc_ops = {
427 .proc = rs5c372_rtc_proc,
428 .read_time = rs5c372_rtc_read_time,
429 .set_time = rs5c372_rtc_set_time,
430 .read_alarm = rs5c_read_alarm,
431 .set_alarm = rs5c_set_alarm,
432 .alarm_irq_enable = rs5c_rtc_alarm_irq_enable,
433};
434
435#if IS_ENABLED(CONFIG_RTC_INTF_SYSFS)
436
437static 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}
448static DEVICE_ATTR(trim, S_IRUGO, rs5c372_sysfs_show_trim, NULL);
449
450static 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}
461static DEVICE_ATTR(osc, S_IRUGO, rs5c372_sysfs_show_osc, NULL);
462
463static 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
477static 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
484static int rs5c_sysfs_register(struct device *dev)
485{
486 return 0;
487}
488
489static void rs5c_sysfs_unregister(struct device *dev)
490{
491 /* nothing */
492}
493#endif /* SYSFS */
494
495static struct i2c_driver rs5c372_driver;
496
497static int rs5c_oscillator_setup(struct rs5c372 *rs5c372)
498{
499 unsigned char buf[2];
500 int addr, i, ret = 0;
501
502 if (rs5c372->type == rtc_r2025sd) {
503 if (rs5c372->regs[RS5C_REG_CTRL2] & R2025_CTRL2_XST)
504 return ret;
505 rs5c372->regs[RS5C_REG_CTRL2] |= R2025_CTRL2_XST;
506 } else {
507 if (!(rs5c372->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_XSTP))
508 return ret;
509 rs5c372->regs[RS5C_REG_CTRL2] &= ~RS5C_CTRL2_XSTP;
510 }
511
512 addr = RS5C_ADDR(RS5C_REG_CTRL1);
513 buf[0] = rs5c372->regs[RS5C_REG_CTRL1];
514 buf[1] = rs5c372->regs[RS5C_REG_CTRL2];
515
516 /* use 24hr mode */
517 switch (rs5c372->type) {
518 case rtc_rs5c372a:
519 case rtc_rs5c372b:
520 buf[1] |= RS5C372_CTRL2_24;
521 rs5c372->time24 = 1;
522 break;
523 case rtc_r2025sd:
524 case rtc_r2221tl:
525 case rtc_rv5c386:
526 case rtc_rv5c387a:
527 buf[0] |= RV5C387_CTRL1_24;
528 rs5c372->time24 = 1;
529 break;
530 default:
531 /* impossible */
532 break;
533 }
534
535 for (i = 0; i < sizeof(buf); i++) {
536 addr = RS5C_ADDR(RS5C_REG_CTRL1 + i);
537 ret = i2c_smbus_write_byte_data(rs5c372->client, addr, buf[i]);
538 if (unlikely(ret < 0))
539 return ret;
540 }
541
542 rs5c372->regs[RS5C_REG_CTRL1] = buf[0];
543 rs5c372->regs[RS5C_REG_CTRL2] = buf[1];
544
545 return 0;
546}
547
548static int rs5c372_probe(struct i2c_client *client,
549 const struct i2c_device_id *id)
550{
551 int err = 0;
552 int smbus_mode = 0;
553 struct rs5c372 *rs5c372;
554 struct rtc_time tm;
555
556 dev_dbg(&client->dev, "%s\n", __func__);
557
558 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
559 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK)) {
560 /*
561 * If we don't have any master mode adapter, try breaking
562 * it down in to the barest of capabilities.
563 */
564 if (i2c_check_functionality(client->adapter,
565 I2C_FUNC_SMBUS_BYTE_DATA |
566 I2C_FUNC_SMBUS_I2C_BLOCK))
567 smbus_mode = 1;
568 else {
569 /* Still no good, give up */
570 err = -ENODEV;
571 goto exit;
572 }
573 }
574
575 rs5c372 = devm_kzalloc(&client->dev, sizeof(struct rs5c372),
576 GFP_KERNEL);
577 if (!rs5c372) {
578 err = -ENOMEM;
579 goto exit;
580 }
581
582 rs5c372->client = client;
583 i2c_set_clientdata(client, rs5c372);
584 rs5c372->type = id->driver_data;
585
586 /* we read registers 0x0f then 0x00-0x0f; skip the first one */
587 rs5c372->regs = &rs5c372->buf[1];
588 rs5c372->smbus = smbus_mode;
589
590 err = rs5c_get_regs(rs5c372);
591 if (err < 0)
592 goto exit;
593
594 /* clock may be set for am/pm or 24 hr time */
595 switch (rs5c372->type) {
596 case rtc_rs5c372a:
597 case rtc_rs5c372b:
598 /* alarm uses ALARM_A; and nINTRA on 372a, nINTR on 372b.
599 * so does periodic irq, except some 327a modes.
600 */
601 if (rs5c372->regs[RS5C_REG_CTRL2] & RS5C372_CTRL2_24)
602 rs5c372->time24 = 1;
603 break;
604 case rtc_r2025sd:
605 case rtc_r2221tl:
606 case rtc_rv5c386:
607 case rtc_rv5c387a:
608 if (rs5c372->regs[RS5C_REG_CTRL1] & RV5C387_CTRL1_24)
609 rs5c372->time24 = 1;
610 /* alarm uses ALARM_W; and nINTRB for alarm and periodic
611 * irq, on both 386 and 387
612 */
613 break;
614 default:
615 dev_err(&client->dev, "unknown RTC type\n");
616 goto exit;
617 }
618
619 /* if the oscillator lost power and no other software (like
620 * the bootloader) set it up, do it here.
621 *
622 * The R2025S/D does this a little differently than the other
623 * parts, so we special case that..
624 */
625 err = rs5c_oscillator_setup(rs5c372);
626 if (unlikely(err < 0)) {
627 dev_err(&client->dev, "setup error\n");
628 goto exit;
629 }
630
631 if (rs5c372_get_datetime(client, &tm) < 0)
632 dev_warn(&client->dev, "clock needs to be set\n");
633
634 dev_info(&client->dev, "%s found, %s\n",
635 ({ char *s; switch (rs5c372->type) {
636 case rtc_r2025sd: s = "r2025sd"; break;
637 case rtc_r2221tl: s = "r2221tl"; break;
638 case rtc_rs5c372a: s = "rs5c372a"; break;
639 case rtc_rs5c372b: s = "rs5c372b"; break;
640 case rtc_rv5c386: s = "rv5c386"; break;
641 case rtc_rv5c387a: s = "rv5c387a"; break;
642 default: s = "chip"; break;
643 }; s;}),
644 rs5c372->time24 ? "24hr" : "am/pm"
645 );
646
647 /* REVISIT use client->irq to register alarm irq ... */
648 rs5c372->rtc = devm_rtc_device_register(&client->dev,
649 rs5c372_driver.driver.name,
650 &rs5c372_rtc_ops, THIS_MODULE);
651
652 if (IS_ERR(rs5c372->rtc)) {
653 err = PTR_ERR(rs5c372->rtc);
654 goto exit;
655 }
656
657 err = rs5c_sysfs_register(&client->dev);
658 if (err)
659 goto exit;
660
661 return 0;
662
663exit:
664 return err;
665}
666
667static int rs5c372_remove(struct i2c_client *client)
668{
669 rs5c_sysfs_unregister(&client->dev);
670 return 0;
671}
672
673static struct i2c_driver rs5c372_driver = {
674 .driver = {
675 .name = "rtc-rs5c372",
676 },
677 .probe = rs5c372_probe,
678 .remove = rs5c372_remove,
679 .id_table = rs5c372_id,
680};
681
682module_i2c_driver(rs5c372_driver);
683
684MODULE_AUTHOR(
685 "Pavel Mironchik <pmironchik@optifacio.net>, "
686 "Alessandro Zummo <a.zummo@towertech.it>, "
687 "Paul Mundt <lethal@linux-sh.org>");
688MODULE_DESCRIPTION("Ricoh RS5C372 RTC driver");
689MODULE_LICENSE("GPL");