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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/rtc/
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
18#define DRV_VERSION "0.6"
19
20
21/*
22 * Ricoh has a family of I2C based RTCs, which differ only slightly from
23 * each other.  Differences center on pinout (e.g. how many interrupts,
24 * output clock, etc) and how the control registers are used.  The '372
25 * is significant only because that's the one this driver first supported.
26 */
27#define RS5C372_REG_SECS	0
28#define RS5C372_REG_MINS	1
29#define RS5C372_REG_HOURS	2
30#define RS5C372_REG_WDAY	3
31#define RS5C372_REG_DAY		4
32#define RS5C372_REG_MONTH	5
33#define RS5C372_REG_YEAR	6
34#define RS5C372_REG_TRIM	7
35#	define RS5C372_TRIM_XSL		0x80
36#	define RS5C372_TRIM_MASK	0x7F
37
38#define RS5C_REG_ALARM_A_MIN	8			/* or ALARM_W */
39#define RS5C_REG_ALARM_A_HOURS	9
40#define RS5C_REG_ALARM_A_WDAY	10
41
42#define RS5C_REG_ALARM_B_MIN	11			/* or ALARM_D */
43#define RS5C_REG_ALARM_B_HOURS	12
44#define RS5C_REG_ALARM_B_WDAY	13			/* (ALARM_B only) */
45
46#define RS5C_REG_CTRL1		14
47#	define RS5C_CTRL1_AALE		(1 << 7)	/* or WALE */
48#	define RS5C_CTRL1_BALE		(1 << 6)	/* or DALE */
49#	define RV5C387_CTRL1_24		(1 << 5)
50#	define RS5C372A_CTRL1_SL1	(1 << 5)
51#	define RS5C_CTRL1_CT_MASK	(7 << 0)
52#	define RS5C_CTRL1_CT0		(0 << 0)	/* no periodic irq */
53#	define RS5C_CTRL1_CT4		(4 << 0)	/* 1 Hz level irq */
54#define RS5C_REG_CTRL2		15
55#	define RS5C372_CTRL2_24		(1 << 5)
56#	define R2025_CTRL2_XST		(1 << 5)
57#	define RS5C_CTRL2_XSTP		(1 << 4)	/* only if !R2025S/D */
58#	define RS5C_CTRL2_CTFG		(1 << 2)
59#	define RS5C_CTRL2_AAFG		(1 << 1)	/* or WAFG */
60#	define RS5C_CTRL2_BAFG		(1 << 0)	/* or DAFG */
61
62
63/* to read (style 1) or write registers starting at R */
64#define RS5C_ADDR(R)		(((R) << 4) | 0)
65
66
67enum rtc_type {
68	rtc_undef = 0,
69	rtc_r2025sd,
70	rtc_rs5c372a,
71	rtc_rs5c372b,
72	rtc_rv5c386,
73	rtc_rv5c387a,
74};
75
76static const struct i2c_device_id rs5c372_id[] = {
77	{ "r2025sd", rtc_r2025sd },
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		{ client->addr, I2C_M_RD, sizeof rs5c->buf, rs5c->buf },
107	};
108
109	/* This implements the third reading method from the datasheet, using
110	 * an internal address that's reset after each transaction (by STOP)
111	 * to 0x0f ... so we read extra registers, and skip the first one.
112	 *
113	 * The first method doesn't work with the iop3xx adapter driver, on at
114	 * least 80219 chips; this works around that bug.
115	 *
116	 * The third method on the other hand doesn't work for the SMBus-only
117	 * configurations, so we use the the first method there, stripping off
118	 * the extra register in the process.
119	 */
120	if (rs5c->smbus) {
121		int addr = RS5C_ADDR(RS5C372_REG_SECS);
122		int size = sizeof(rs5c->buf) - 1;
123
124		if (i2c_smbus_read_i2c_block_data(client, addr, size,
125						  rs5c->buf + 1) != size) {
126			dev_warn(&client->dev, "can't read registers\n");
127			return -EIO;
128		}
129	} else {
130		if ((i2c_transfer(client->adapter, msgs, 1)) != 1) {
131			dev_warn(&client->dev, "can't read registers\n");
132			return -EIO;
133		}
134	}
135
136	dev_dbg(&client->dev,
137		"%02x %02x %02x (%02x) %02x %02x %02x (%02x), "
138		"%02x %02x %02x, %02x %02x %02x; %02x %02x\n",
139		rs5c->regs[0],  rs5c->regs[1],  rs5c->regs[2],  rs5c->regs[3],
140		rs5c->regs[4],  rs5c->regs[5],  rs5c->regs[6],  rs5c->regs[7],
141		rs5c->regs[8],  rs5c->regs[9],  rs5c->regs[10], rs5c->regs[11],
142		rs5c->regs[12], rs5c->regs[13], rs5c->regs[14], rs5c->regs[15]);
143
144	return 0;
145}
146
147static unsigned rs5c_reg2hr(struct rs5c372 *rs5c, unsigned reg)
148{
149	unsigned	hour;
150
151	if (rs5c->time24)
152		return bcd2bin(reg & 0x3f);
153
154	hour = bcd2bin(reg & 0x1f);
155	if (hour == 12)
156		hour = 0;
157	if (reg & 0x20)
158		hour += 12;
159	return hour;
160}
161
162static unsigned rs5c_hr2reg(struct rs5c372 *rs5c, unsigned hour)
163{
164	if (rs5c->time24)
165		return bin2bcd(hour);
166
167	if (hour > 12)
168		return 0x20 | bin2bcd(hour - 12);
169	if (hour == 12)
170		return 0x20 | bin2bcd(12);
171	if (hour == 0)
172		return bin2bcd(12);
173	return bin2bcd(hour);
174}
175
176static int rs5c372_get_datetime(struct i2c_client *client, struct rtc_time *tm)
177{
178	struct rs5c372	*rs5c = i2c_get_clientdata(client);
179	int		status = rs5c_get_regs(rs5c);
180
181	if (status < 0)
182		return status;
183
184	tm->tm_sec = bcd2bin(rs5c->regs[RS5C372_REG_SECS] & 0x7f);
185	tm->tm_min = bcd2bin(rs5c->regs[RS5C372_REG_MINS] & 0x7f);
186	tm->tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C372_REG_HOURS]);
187
188	tm->tm_wday = bcd2bin(rs5c->regs[RS5C372_REG_WDAY] & 0x07);
189	tm->tm_mday = bcd2bin(rs5c->regs[RS5C372_REG_DAY] & 0x3f);
190
191	/* tm->tm_mon is zero-based */
192	tm->tm_mon = bcd2bin(rs5c->regs[RS5C372_REG_MONTH] & 0x1f) - 1;
193
194	/* year is 1900 + tm->tm_year */
195	tm->tm_year = bcd2bin(rs5c->regs[RS5C372_REG_YEAR]) + 100;
196
197	dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
198		"mday=%d, mon=%d, year=%d, wday=%d\n",
199		__func__,
200		tm->tm_sec, tm->tm_min, tm->tm_hour,
201		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
202
203	/* rtc might need initialization */
204	return rtc_valid_tm(tm);
205}
206
207static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm)
208{
209	struct rs5c372	*rs5c = i2c_get_clientdata(client);
210	unsigned char	buf[7];
211	int		addr;
212
213	dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d "
214		"mday=%d, mon=%d, year=%d, wday=%d\n",
215		__func__,
216		tm->tm_sec, tm->tm_min, tm->tm_hour,
217		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
218
219	addr   = RS5C_ADDR(RS5C372_REG_SECS);
220	buf[0] = bin2bcd(tm->tm_sec);
221	buf[1] = bin2bcd(tm->tm_min);
222	buf[2] = rs5c_hr2reg(rs5c, tm->tm_hour);
223	buf[3] = bin2bcd(tm->tm_wday);
224	buf[4] = bin2bcd(tm->tm_mday);
225	buf[5] = bin2bcd(tm->tm_mon + 1);
226	buf[6] = bin2bcd(tm->tm_year - 100);
227
228	if (i2c_smbus_write_i2c_block_data(client, addr, sizeof(buf), buf) < 0) {
229		dev_err(&client->dev, "%s: write error\n", __func__);
230		return -EIO;
231	}
232
233	return 0;
234}
235
236#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
237#define	NEED_TRIM
238#endif
239
240#if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
241#define	NEED_TRIM
242#endif
243
244#ifdef	NEED_TRIM
245static int rs5c372_get_trim(struct i2c_client *client, int *osc, int *trim)
246{
247	struct rs5c372 *rs5c372 = i2c_get_clientdata(client);
248	u8 tmp = rs5c372->regs[RS5C372_REG_TRIM];
249
250	if (osc)
251		*osc = (tmp & RS5C372_TRIM_XSL) ? 32000 : 32768;
252
253	if (trim) {
254		dev_dbg(&client->dev, "%s: raw trim=%x\n", __func__, tmp);
255		tmp &= RS5C372_TRIM_MASK;
256		if (tmp & 0x3e) {
257			int t = tmp & 0x3f;
258
259			if (tmp & 0x40)
260				t = (~t | (s8)0xc0) + 1;
261			else
262				t = t - 1;
263
264			tmp = t * 2;
265		} else
266			tmp = 0;
267		*trim = tmp;
268	}
269
270	return 0;
271}
272#endif
273
274static int rs5c372_rtc_read_time(struct device *dev, struct rtc_time *tm)
275{
276	return rs5c372_get_datetime(to_i2c_client(dev), tm);
277}
278
279static int rs5c372_rtc_set_time(struct device *dev, struct rtc_time *tm)
280{
281	return rs5c372_set_datetime(to_i2c_client(dev), tm);
282}
283
284#if defined(CONFIG_RTC_INTF_DEV) || defined(CONFIG_RTC_INTF_DEV_MODULE)
285
286static int
287rs5c_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
288{
289	struct i2c_client	*client = to_i2c_client(dev);
290	struct rs5c372		*rs5c = i2c_get_clientdata(client);
291	unsigned char		buf;
292	int			status, addr;
293
294	buf = rs5c->regs[RS5C_REG_CTRL1];
295	switch (cmd) {
296	case RTC_UIE_OFF:
297	case RTC_UIE_ON:
298		/* some 327a modes use a different IRQ pin for 1Hz irqs */
299		if (rs5c->type == rtc_rs5c372a
300				&& (buf & RS5C372A_CTRL1_SL1))
301			return -ENOIOCTLCMD;
302	case RTC_AIE_OFF:
303	case RTC_AIE_ON:
304		/* these irq management calls only make sense for chips
305		 * which are wired up to an IRQ.
306		 */
307		if (!rs5c->has_irq)
308			return -ENOIOCTLCMD;
309		break;
310	default:
311		return -ENOIOCTLCMD;
312	}
313
314	status = rs5c_get_regs(rs5c);
315	if (status < 0)
316		return status;
317
318	addr = RS5C_ADDR(RS5C_REG_CTRL1);
319	switch (cmd) {
320	case RTC_AIE_OFF:	/* alarm off */
321		buf &= ~RS5C_CTRL1_AALE;
322		break;
323	case RTC_AIE_ON:	/* alarm on */
324		buf |= RS5C_CTRL1_AALE;
325		break;
326	case RTC_UIE_OFF:	/* update off */
327		buf &= ~RS5C_CTRL1_CT_MASK;
328		break;
329	case RTC_UIE_ON:	/* update on */
330		buf &= ~RS5C_CTRL1_CT_MASK;
331		buf |= RS5C_CTRL1_CT4;
332		break;
333	}
334
335	if (i2c_smbus_write_byte_data(client, addr, buf) < 0) {
336		printk(KERN_WARNING "%s: can't update alarm\n",
337			rs5c->rtc->name);
338		status = -EIO;
339	} else
340		rs5c->regs[RS5C_REG_CTRL1] = buf;
341
342	return status;
343}
344
345#else
346#define	rs5c_rtc_ioctl	NULL
347#endif
348
349
350/* NOTE:  Since RTC_WKALM_{RD,SET} were originally defined for EFI,
351 * which only exposes a polled programming interface; and since
352 * these calls map directly to those EFI requests; we don't demand
353 * we have an IRQ for this chip when we go through this API.
354 *
355 * The older x86_pc derived RTC_ALM_{READ,SET} calls require irqs
356 * though, managed through RTC_AIE_{ON,OFF} requests.
357 */
358
359static int rs5c_read_alarm(struct device *dev, struct rtc_wkalrm *t)
360{
361	struct i2c_client	*client = to_i2c_client(dev);
362	struct rs5c372		*rs5c = i2c_get_clientdata(client);
363	int			status;
364
365	status = rs5c_get_regs(rs5c);
366	if (status < 0)
367		return status;
368
369	/* report alarm time */
370	t->time.tm_sec = 0;
371	t->time.tm_min = bcd2bin(rs5c->regs[RS5C_REG_ALARM_A_MIN] & 0x7f);
372	t->time.tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C_REG_ALARM_A_HOURS]);
373	t->time.tm_mday = -1;
374	t->time.tm_mon = -1;
375	t->time.tm_year = -1;
376	t->time.tm_wday = -1;
377	t->time.tm_yday = -1;
378	t->time.tm_isdst = -1;
379
380	/* ... and status */
381	t->enabled = !!(rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE);
382	t->pending = !!(rs5c->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_AAFG);
383
384	return 0;
385}
386
387static int rs5c_set_alarm(struct device *dev, struct rtc_wkalrm *t)
388{
389	struct i2c_client	*client = to_i2c_client(dev);
390	struct rs5c372		*rs5c = i2c_get_clientdata(client);
391	int			status, addr, i;
392	unsigned char		buf[3];
393
394	/* only handle up to 24 hours in the future, like RTC_ALM_SET */
395	if (t->time.tm_mday != -1
396			|| t->time.tm_mon != -1
397			|| t->time.tm_year != -1)
398		return -EINVAL;
399
400	/* REVISIT: round up tm_sec */
401
402	/* if needed, disable irq (clears pending status) */
403	status = rs5c_get_regs(rs5c);
404	if (status < 0)
405		return status;
406	if (rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE) {
407		addr = RS5C_ADDR(RS5C_REG_CTRL1);
408		buf[0] = rs5c->regs[RS5C_REG_CTRL1] & ~RS5C_CTRL1_AALE;
409		if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0) {
410			pr_debug("%s: can't disable alarm\n", rs5c->rtc->name);
411			return -EIO;
412		}
413		rs5c->regs[RS5C_REG_CTRL1] = buf[0];
414	}
415
416	/* set alarm */
417	buf[0] = bin2bcd(t->time.tm_min);
418	buf[1] = rs5c_hr2reg(rs5c, t->time.tm_hour);
419	buf[2] = 0x7f;	/* any/all days */
420
421	for (i = 0; i < sizeof(buf); i++) {
422		addr = RS5C_ADDR(RS5C_REG_ALARM_A_MIN + i);
423		if (i2c_smbus_write_byte_data(client, addr, buf[i]) < 0) {
424			pr_debug("%s: can't set alarm time\n", rs5c->rtc->name);
425			return -EIO;
426		}
427	}
428
429	/* ... and maybe enable its irq */
430	if (t->enabled) {
431		addr = RS5C_ADDR(RS5C_REG_CTRL1);
432		buf[0] = rs5c->regs[RS5C_REG_CTRL1] | RS5C_CTRL1_AALE;
433		if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0)
434			printk(KERN_WARNING "%s: can't enable alarm\n",
435				rs5c->rtc->name);
436		rs5c->regs[RS5C_REG_CTRL1] = buf[0];
437	}
438
439	return 0;
440}
441
442#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
443
444static int rs5c372_rtc_proc(struct device *dev, struct seq_file *seq)
445{
446	int err, osc, trim;
447
448	err = rs5c372_get_trim(to_i2c_client(dev), &osc, &trim);
449	if (err == 0) {
450		seq_printf(seq, "crystal\t\t: %d.%03d KHz\n",
451				osc / 1000, osc % 1000);
452		seq_printf(seq, "trim\t\t: %d\n", trim);
453	}
454
455	return 0;
456}
457
458#else
459#define	rs5c372_rtc_proc	NULL
460#endif
461
462static const struct rtc_class_ops rs5c372_rtc_ops = {
463	.proc		= rs5c372_rtc_proc,
464	.ioctl		= rs5c_rtc_ioctl,
465	.read_time	= rs5c372_rtc_read_time,
466	.set_time	= rs5c372_rtc_set_time,
467	.read_alarm	= rs5c_read_alarm,
468	.set_alarm	= rs5c_set_alarm,
469};
470
471#if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
472
473static ssize_t rs5c372_sysfs_show_trim(struct device *dev,
474				struct device_attribute *attr, char *buf)
475{
476	int err, trim;
477
478	err = rs5c372_get_trim(to_i2c_client(dev), NULL, &trim);
479	if (err)
480		return err;
481
482	return sprintf(buf, "%d\n", trim);
483}
484static DEVICE_ATTR(trim, S_IRUGO, rs5c372_sysfs_show_trim, NULL);
485
486static ssize_t rs5c372_sysfs_show_osc(struct device *dev,
487				struct device_attribute *attr, char *buf)
488{
489	int err, osc;
490
491	err = rs5c372_get_trim(to_i2c_client(dev), &osc, NULL);
492	if (err)
493		return err;
494
495	return sprintf(buf, "%d.%03d KHz\n", osc / 1000, osc % 1000);
496}
497static DEVICE_ATTR(osc, S_IRUGO, rs5c372_sysfs_show_osc, NULL);
498
499static int rs5c_sysfs_register(struct device *dev)
500{
501	int err;
502
503	err = device_create_file(dev, &dev_attr_trim);
504	if (err)
505		return err;
506	err = device_create_file(dev, &dev_attr_osc);
507	if (err)
508		device_remove_file(dev, &dev_attr_trim);
509
510	return err;
511}
512
513static void rs5c_sysfs_unregister(struct device *dev)
514{
515	device_remove_file(dev, &dev_attr_trim);
516	device_remove_file(dev, &dev_attr_osc);
517}
518
519#else
520static int rs5c_sysfs_register(struct device *dev)
521{
522	return 0;
523}
524
525static void rs5c_sysfs_unregister(struct device *dev)
526{
527	/* nothing */
528}
529#endif	/* SYSFS */
530
531static struct i2c_driver rs5c372_driver;
532
533static int rs5c_oscillator_setup(struct rs5c372 *rs5c372)
534{
535	unsigned char buf[2];
536	int addr, i, ret = 0;
537
538	if (rs5c372->type == rtc_r2025sd) {
539		if (!(rs5c372->regs[RS5C_REG_CTRL2] & R2025_CTRL2_XST))
540			return ret;
541		rs5c372->regs[RS5C_REG_CTRL2] &= ~R2025_CTRL2_XST;
542	} else {
543		if (!(rs5c372->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_XSTP))
544			return ret;
545		rs5c372->regs[RS5C_REG_CTRL2] &= ~RS5C_CTRL2_XSTP;
546	}
547
548	addr   = RS5C_ADDR(RS5C_REG_CTRL1);
549	buf[0] = rs5c372->regs[RS5C_REG_CTRL1];
550	buf[1] = rs5c372->regs[RS5C_REG_CTRL2];
551
552	/* use 24hr mode */
553	switch (rs5c372->type) {
554	case rtc_rs5c372a:
555	case rtc_rs5c372b:
556		buf[1] |= RS5C372_CTRL2_24;
557		rs5c372->time24 = 1;
558		break;
559	case rtc_r2025sd:
560	case rtc_rv5c386:
561	case rtc_rv5c387a:
562		buf[0] |= RV5C387_CTRL1_24;
563		rs5c372->time24 = 1;
564		break;
565	default:
566		/* impossible */
567		break;
568	}
569
570	for (i = 0; i < sizeof(buf); i++) {
571		addr = RS5C_ADDR(RS5C_REG_CTRL1 + i);
572		ret = i2c_smbus_write_byte_data(rs5c372->client, addr, buf[i]);
573		if (unlikely(ret < 0))
574			return ret;
575	}
576
577	rs5c372->regs[RS5C_REG_CTRL1] = buf[0];
578	rs5c372->regs[RS5C_REG_CTRL2] = buf[1];
579
580	return 0;
581}
582
583static int rs5c372_probe(struct i2c_client *client,
584			 const struct i2c_device_id *id)
585{
586	int err = 0;
587	int smbus_mode = 0;
588	struct rs5c372 *rs5c372;
589	struct rtc_time tm;
590
591	dev_dbg(&client->dev, "%s\n", __func__);
592
593	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
594			I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK)) {
595		/*
596		 * If we don't have any master mode adapter, try breaking
597		 * it down in to the barest of capabilities.
598		 */
599		if (i2c_check_functionality(client->adapter,
600				I2C_FUNC_SMBUS_BYTE_DATA |
601				I2C_FUNC_SMBUS_I2C_BLOCK))
602			smbus_mode = 1;
603		else {
604			/* Still no good, give up */
605			err = -ENODEV;
606			goto exit;
607		}
608	}
609
610	if (!(rs5c372 = kzalloc(sizeof(struct rs5c372), GFP_KERNEL))) {
611		err = -ENOMEM;
612		goto exit;
613	}
614
615	rs5c372->client = client;
616	i2c_set_clientdata(client, rs5c372);
617	rs5c372->type = id->driver_data;
618
619	/* we read registers 0x0f then 0x00-0x0f; skip the first one */
620	rs5c372->regs = &rs5c372->buf[1];
621	rs5c372->smbus = smbus_mode;
622
623	err = rs5c_get_regs(rs5c372);
624	if (err < 0)
625		goto exit_kfree;
626
627	/* clock may be set for am/pm or 24 hr time */
628	switch (rs5c372->type) {
629	case rtc_rs5c372a:
630	case rtc_rs5c372b:
631		/* alarm uses ALARM_A; and nINTRA on 372a, nINTR on 372b.
632		 * so does periodic irq, except some 327a modes.
633		 */
634		if (rs5c372->regs[RS5C_REG_CTRL2] & RS5C372_CTRL2_24)
635			rs5c372->time24 = 1;
636		break;
637	case rtc_r2025sd:
638	case rtc_rv5c386:
639	case rtc_rv5c387a:
640		if (rs5c372->regs[RS5C_REG_CTRL1] & RV5C387_CTRL1_24)
641			rs5c372->time24 = 1;
642		/* alarm uses ALARM_W; and nINTRB for alarm and periodic
643		 * irq, on both 386 and 387
644		 */
645		break;
646	default:
647		dev_err(&client->dev, "unknown RTC type\n");
648		goto exit_kfree;
649	}
650
651	/* if the oscillator lost power and no other software (like
652	 * the bootloader) set it up, do it here.
653	 *
654	 * The R2025S/D does this a little differently than the other
655	 * parts, so we special case that..
656	 */
657	err = rs5c_oscillator_setup(rs5c372);
658	if (unlikely(err < 0)) {
659		dev_err(&client->dev, "setup error\n");
660		goto exit_kfree;
661	}
662
663	if (rs5c372_get_datetime(client, &tm) < 0)
664		dev_warn(&client->dev, "clock needs to be set\n");
665
666	dev_info(&client->dev, "%s found, %s, driver version " DRV_VERSION "\n",
667			({ char *s; switch (rs5c372->type) {
668			case rtc_r2025sd:	s = "r2025sd"; break;
669			case rtc_rs5c372a:	s = "rs5c372a"; break;
670			case rtc_rs5c372b:	s = "rs5c372b"; break;
671			case rtc_rv5c386:	s = "rv5c386"; break;
672			case rtc_rv5c387a:	s = "rv5c387a"; break;
673			default:		s = "chip"; break;
674			}; s;}),
675			rs5c372->time24 ? "24hr" : "am/pm"
676			);
677
678	/* REVISIT use client->irq to register alarm irq ... */
679
680	rs5c372->rtc = rtc_device_register(rs5c372_driver.driver.name,
681				&client->dev, &rs5c372_rtc_ops, THIS_MODULE);
682
683	if (IS_ERR(rs5c372->rtc)) {
684		err = PTR_ERR(rs5c372->rtc);
685		goto exit_kfree;
686	}
687
688	err = rs5c_sysfs_register(&client->dev);
689	if (err)
690		goto exit_devreg;
691
692	return 0;
693
694exit_devreg:
695	rtc_device_unregister(rs5c372->rtc);
696
697exit_kfree:
698	kfree(rs5c372);
699
700exit:
701	return err;
702}
703
704static int rs5c372_remove(struct i2c_client *client)
705{
706	struct rs5c372 *rs5c372 = i2c_get_clientdata(client);
707
708	rtc_device_unregister(rs5c372->rtc);
709	rs5c_sysfs_unregister(&client->dev);
710	kfree(rs5c372);
711	return 0;
712}
713
714static struct i2c_driver rs5c372_driver = {
715	.driver		= {
716		.name	= "rtc-rs5c372",
717	},
718	.probe		= rs5c372_probe,
719	.remove		= rs5c372_remove,
720	.id_table	= rs5c372_id,
721};
722
723static __init int rs5c372_init(void)
724{
725	return i2c_add_driver(&rs5c372_driver);
726}
727
728static __exit void rs5c372_exit(void)
729{
730	i2c_del_driver(&rs5c372_driver);
731}
732
733module_init(rs5c372_init);
734module_exit(rs5c372_exit);
735
736MODULE_AUTHOR(
737		"Pavel Mironchik <pmironchik@optifacio.net>, "
738		"Alessandro Zummo <a.zummo@towertech.it>, "
739		"Paul Mundt <lethal@linux-sh.org>");
740MODULE_DESCRIPTION("Ricoh RS5C372 RTC driver");
741MODULE_LICENSE("GPL");
742MODULE_VERSION(DRV_VERSION);
743