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v3.5.6
  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_rs5c372a,
 72	rtc_rs5c372b,
 73	rtc_rv5c386,
 74	rtc_rv5c387a,
 75};
 76
 77static const struct i2c_device_id rs5c372_id[] = {
 78	{ "r2025sd", rtc_r2025sd },
 
 79	{ "rs5c372a", rtc_rs5c372a },
 80	{ "rs5c372b", rtc_rs5c372b },
 81	{ "rv5c386", rtc_rv5c386 },
 82	{ "rv5c387a", rtc_rv5c387a },
 83	{ }
 84};
 85MODULE_DEVICE_TABLE(i2c, rs5c372_id);
 86
 87/* REVISIT:  this assumes that:
 88 *  - we're in the 21st century, so it's safe to ignore the century
 89 *    bit for rv5c38[67] (REG_MONTH bit 7);
 90 *  - we should use ALARM_A not ALARM_B (may be wrong on some boards)
 91 */
 92struct rs5c372 {
 93	struct i2c_client	*client;
 94	struct rtc_device	*rtc;
 95	enum rtc_type		type;
 96	unsigned		time24:1;
 97	unsigned		has_irq:1;
 98	unsigned		smbus:1;
 99	char			buf[17];
100	char			*regs;
101};
102
103static int rs5c_get_regs(struct rs5c372 *rs5c)
104{
105	struct i2c_client	*client = rs5c->client;
106	struct i2c_msg		msgs[] = {
107		{ client->addr, I2C_M_RD, sizeof rs5c->buf, rs5c->buf },
 
 
 
 
 
108	};
109
110	/* This implements the third reading method from the datasheet, using
111	 * an internal address that's reset after each transaction (by STOP)
112	 * to 0x0f ... so we read extra registers, and skip the first one.
113	 *
114	 * The first method doesn't work with the iop3xx adapter driver, on at
115	 * least 80219 chips; this works around that bug.
116	 *
117	 * The third method on the other hand doesn't work for the SMBus-only
118	 * configurations, so we use the the first method there, stripping off
119	 * the extra register in the process.
120	 */
121	if (rs5c->smbus) {
122		int addr = RS5C_ADDR(RS5C372_REG_SECS);
123		int size = sizeof(rs5c->buf) - 1;
124
125		if (i2c_smbus_read_i2c_block_data(client, addr, size,
126						  rs5c->buf + 1) != size) {
127			dev_warn(&client->dev, "can't read registers\n");
128			return -EIO;
129		}
130	} else {
131		if ((i2c_transfer(client->adapter, msgs, 1)) != 1) {
132			dev_warn(&client->dev, "can't read registers\n");
133			return -EIO;
134		}
135	}
136
137	dev_dbg(&client->dev,
138		"%02x %02x %02x (%02x) %02x %02x %02x (%02x), "
139		"%02x %02x %02x, %02x %02x %02x; %02x %02x\n",
140		rs5c->regs[0],  rs5c->regs[1],  rs5c->regs[2],  rs5c->regs[3],
141		rs5c->regs[4],  rs5c->regs[5],  rs5c->regs[6],  rs5c->regs[7],
142		rs5c->regs[8],  rs5c->regs[9],  rs5c->regs[10], rs5c->regs[11],
143		rs5c->regs[12], rs5c->regs[13], rs5c->regs[14], rs5c->regs[15]);
144
145	return 0;
146}
147
148static unsigned rs5c_reg2hr(struct rs5c372 *rs5c, unsigned reg)
149{
150	unsigned	hour;
151
152	if (rs5c->time24)
153		return bcd2bin(reg & 0x3f);
154
155	hour = bcd2bin(reg & 0x1f);
156	if (hour == 12)
157		hour = 0;
158	if (reg & 0x20)
159		hour += 12;
160	return hour;
161}
162
163static unsigned rs5c_hr2reg(struct rs5c372 *rs5c, unsigned hour)
164{
165	if (rs5c->time24)
166		return bin2bcd(hour);
167
168	if (hour > 12)
169		return 0x20 | bin2bcd(hour - 12);
170	if (hour == 12)
171		return 0x20 | bin2bcd(12);
172	if (hour == 0)
173		return bin2bcd(12);
174	return bin2bcd(hour);
175}
176
177static int rs5c372_get_datetime(struct i2c_client *client, struct rtc_time *tm)
178{
179	struct rs5c372	*rs5c = i2c_get_clientdata(client);
180	int		status = rs5c_get_regs(rs5c);
181
182	if (status < 0)
183		return status;
184
185	tm->tm_sec = bcd2bin(rs5c->regs[RS5C372_REG_SECS] & 0x7f);
186	tm->tm_min = bcd2bin(rs5c->regs[RS5C372_REG_MINS] & 0x7f);
187	tm->tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C372_REG_HOURS]);
188
189	tm->tm_wday = bcd2bin(rs5c->regs[RS5C372_REG_WDAY] & 0x07);
190	tm->tm_mday = bcd2bin(rs5c->regs[RS5C372_REG_DAY] & 0x3f);
191
192	/* tm->tm_mon is zero-based */
193	tm->tm_mon = bcd2bin(rs5c->regs[RS5C372_REG_MONTH] & 0x1f) - 1;
194
195	/* year is 1900 + tm->tm_year */
196	tm->tm_year = bcd2bin(rs5c->regs[RS5C372_REG_YEAR]) + 100;
197
198	dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
199		"mday=%d, mon=%d, year=%d, wday=%d\n",
200		__func__,
201		tm->tm_sec, tm->tm_min, tm->tm_hour,
202		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
203
204	/* rtc might need initialization */
205	return rtc_valid_tm(tm);
206}
207
208static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm)
209{
210	struct rs5c372	*rs5c = i2c_get_clientdata(client);
211	unsigned char	buf[7];
212	int		addr;
213
214	dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d "
215		"mday=%d, mon=%d, year=%d, wday=%d\n",
216		__func__,
217		tm->tm_sec, tm->tm_min, tm->tm_hour,
218		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
219
220	addr   = RS5C_ADDR(RS5C372_REG_SECS);
221	buf[0] = bin2bcd(tm->tm_sec);
222	buf[1] = bin2bcd(tm->tm_min);
223	buf[2] = rs5c_hr2reg(rs5c, tm->tm_hour);
224	buf[3] = bin2bcd(tm->tm_wday);
225	buf[4] = bin2bcd(tm->tm_mday);
226	buf[5] = bin2bcd(tm->tm_mon + 1);
227	buf[6] = bin2bcd(tm->tm_year - 100);
228
229	if (i2c_smbus_write_i2c_block_data(client, addr, sizeof(buf), buf) < 0) {
230		dev_err(&client->dev, "%s: write error\n", __func__);
231		return -EIO;
232	}
233
234	return 0;
235}
236
237#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
238#define	NEED_TRIM
239#endif
240
241#if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
242#define	NEED_TRIM
243#endif
244
245#ifdef	NEED_TRIM
246static int rs5c372_get_trim(struct i2c_client *client, int *osc, int *trim)
247{
248	struct rs5c372 *rs5c372 = i2c_get_clientdata(client);
249	u8 tmp = rs5c372->regs[RS5C372_REG_TRIM];
250
251	if (osc)
252		*osc = (tmp & RS5C372_TRIM_XSL) ? 32000 : 32768;
253
254	if (trim) {
255		dev_dbg(&client->dev, "%s: raw trim=%x\n", __func__, tmp);
256		tmp &= RS5C372_TRIM_MASK;
257		if (tmp & 0x3e) {
258			int t = tmp & 0x3f;
259
260			if (tmp & 0x40)
261				t = (~t | (s8)0xc0) + 1;
262			else
263				t = t - 1;
264
265			tmp = t * 2;
266		} else
267			tmp = 0;
268		*trim = tmp;
269	}
270
271	return 0;
272}
273#endif
274
275static int rs5c372_rtc_read_time(struct device *dev, struct rtc_time *tm)
276{
277	return rs5c372_get_datetime(to_i2c_client(dev), tm);
278}
279
280static int rs5c372_rtc_set_time(struct device *dev, struct rtc_time *tm)
281{
282	return rs5c372_set_datetime(to_i2c_client(dev), tm);
283}
284
285
286static int rs5c_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
287{
288	struct i2c_client	*client = to_i2c_client(dev);
289	struct rs5c372		*rs5c = i2c_get_clientdata(client);
290	unsigned char		buf;
291	int			status, addr;
292
293	buf = rs5c->regs[RS5C_REG_CTRL1];
294
295	if (!rs5c->has_irq)
296		return -EINVAL;
297
298	status = rs5c_get_regs(rs5c);
299	if (status < 0)
300		return status;
301
302	addr = RS5C_ADDR(RS5C_REG_CTRL1);
303	if (enabled)
304		buf |= RS5C_CTRL1_AALE;
305	else
306		buf &= ~RS5C_CTRL1_AALE;
307
308	if (i2c_smbus_write_byte_data(client, addr, buf) < 0) {
309		printk(KERN_WARNING "%s: can't update alarm\n",
310			rs5c->rtc->name);
311		status = -EIO;
312	} else
313		rs5c->regs[RS5C_REG_CTRL1] = buf;
314
315	return status;
316}
317
318
319/* NOTE:  Since RTC_WKALM_{RD,SET} were originally defined for EFI,
320 * which only exposes a polled programming interface; and since
321 * these calls map directly to those EFI requests; we don't demand
322 * we have an IRQ for this chip when we go through this API.
323 *
324 * The older x86_pc derived RTC_ALM_{READ,SET} calls require irqs
325 * though, managed through RTC_AIE_{ON,OFF} requests.
326 */
327
328static int rs5c_read_alarm(struct device *dev, struct rtc_wkalrm *t)
329{
330	struct i2c_client	*client = to_i2c_client(dev);
331	struct rs5c372		*rs5c = i2c_get_clientdata(client);
332	int			status;
333
334	status = rs5c_get_regs(rs5c);
335	if (status < 0)
336		return status;
337
338	/* report alarm time */
339	t->time.tm_sec = 0;
340	t->time.tm_min = bcd2bin(rs5c->regs[RS5C_REG_ALARM_A_MIN] & 0x7f);
341	t->time.tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C_REG_ALARM_A_HOURS]);
342	t->time.tm_mday = -1;
343	t->time.tm_mon = -1;
344	t->time.tm_year = -1;
345	t->time.tm_wday = -1;
346	t->time.tm_yday = -1;
347	t->time.tm_isdst = -1;
348
349	/* ... and status */
350	t->enabled = !!(rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE);
351	t->pending = !!(rs5c->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_AAFG);
352
353	return 0;
354}
355
356static int rs5c_set_alarm(struct device *dev, struct rtc_wkalrm *t)
357{
358	struct i2c_client	*client = to_i2c_client(dev);
359	struct rs5c372		*rs5c = i2c_get_clientdata(client);
360	int			status, addr, i;
361	unsigned char		buf[3];
362
363	/* only handle up to 24 hours in the future, like RTC_ALM_SET */
364	if (t->time.tm_mday != -1
365			|| t->time.tm_mon != -1
366			|| t->time.tm_year != -1)
367		return -EINVAL;
368
369	/* REVISIT: round up tm_sec */
370
371	/* if needed, disable irq (clears pending status) */
372	status = rs5c_get_regs(rs5c);
373	if (status < 0)
374		return status;
375	if (rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE) {
376		addr = RS5C_ADDR(RS5C_REG_CTRL1);
377		buf[0] = rs5c->regs[RS5C_REG_CTRL1] & ~RS5C_CTRL1_AALE;
378		if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0) {
379			pr_debug("%s: can't disable alarm\n", rs5c->rtc->name);
380			return -EIO;
381		}
382		rs5c->regs[RS5C_REG_CTRL1] = buf[0];
383	}
384
385	/* set alarm */
386	buf[0] = bin2bcd(t->time.tm_min);
387	buf[1] = rs5c_hr2reg(rs5c, t->time.tm_hour);
388	buf[2] = 0x7f;	/* any/all days */
389
390	for (i = 0; i < sizeof(buf); i++) {
391		addr = RS5C_ADDR(RS5C_REG_ALARM_A_MIN + i);
392		if (i2c_smbus_write_byte_data(client, addr, buf[i]) < 0) {
393			pr_debug("%s: can't set alarm time\n", rs5c->rtc->name);
394			return -EIO;
395		}
396	}
397
398	/* ... and maybe enable its irq */
399	if (t->enabled) {
400		addr = RS5C_ADDR(RS5C_REG_CTRL1);
401		buf[0] = rs5c->regs[RS5C_REG_CTRL1] | RS5C_CTRL1_AALE;
402		if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0)
403			printk(KERN_WARNING "%s: can't enable alarm\n",
404				rs5c->rtc->name);
405		rs5c->regs[RS5C_REG_CTRL1] = buf[0];
406	}
407
408	return 0;
409}
410
411#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
412
413static int rs5c372_rtc_proc(struct device *dev, struct seq_file *seq)
414{
415	int err, osc, trim;
416
417	err = rs5c372_get_trim(to_i2c_client(dev), &osc, &trim);
418	if (err == 0) {
419		seq_printf(seq, "crystal\t\t: %d.%03d KHz\n",
420				osc / 1000, osc % 1000);
421		seq_printf(seq, "trim\t\t: %d\n", trim);
422	}
423
424	return 0;
425}
426
427#else
428#define	rs5c372_rtc_proc	NULL
429#endif
430
431static const struct rtc_class_ops rs5c372_rtc_ops = {
432	.proc		= rs5c372_rtc_proc,
433	.read_time	= rs5c372_rtc_read_time,
434	.set_time	= rs5c372_rtc_set_time,
435	.read_alarm	= rs5c_read_alarm,
436	.set_alarm	= rs5c_set_alarm,
437	.alarm_irq_enable = rs5c_rtc_alarm_irq_enable,
438};
439
440#if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
441
442static ssize_t rs5c372_sysfs_show_trim(struct device *dev,
443				struct device_attribute *attr, char *buf)
444{
445	int err, trim;
446
447	err = rs5c372_get_trim(to_i2c_client(dev), NULL, &trim);
448	if (err)
449		return err;
450
451	return sprintf(buf, "%d\n", trim);
452}
453static DEVICE_ATTR(trim, S_IRUGO, rs5c372_sysfs_show_trim, NULL);
454
455static ssize_t rs5c372_sysfs_show_osc(struct device *dev,
456				struct device_attribute *attr, char *buf)
457{
458	int err, osc;
459
460	err = rs5c372_get_trim(to_i2c_client(dev), &osc, NULL);
461	if (err)
462		return err;
463
464	return sprintf(buf, "%d.%03d KHz\n", osc / 1000, osc % 1000);
465}
466static DEVICE_ATTR(osc, S_IRUGO, rs5c372_sysfs_show_osc, NULL);
467
468static int rs5c_sysfs_register(struct device *dev)
469{
470	int err;
471
472	err = device_create_file(dev, &dev_attr_trim);
473	if (err)
474		return err;
475	err = device_create_file(dev, &dev_attr_osc);
476	if (err)
477		device_remove_file(dev, &dev_attr_trim);
478
479	return err;
480}
481
482static void rs5c_sysfs_unregister(struct device *dev)
483{
484	device_remove_file(dev, &dev_attr_trim);
485	device_remove_file(dev, &dev_attr_osc);
486}
487
488#else
489static int rs5c_sysfs_register(struct device *dev)
490{
491	return 0;
492}
493
494static void rs5c_sysfs_unregister(struct device *dev)
495{
496	/* nothing */
497}
498#endif	/* SYSFS */
499
500static struct i2c_driver rs5c372_driver;
501
502static int rs5c_oscillator_setup(struct rs5c372 *rs5c372)
503{
504	unsigned char buf[2];
505	int addr, i, ret = 0;
506
507	if (rs5c372->type == rtc_r2025sd) {
508		if (!(rs5c372->regs[RS5C_REG_CTRL2] & R2025_CTRL2_XST))
509			return ret;
510		rs5c372->regs[RS5C_REG_CTRL2] &= ~R2025_CTRL2_XST;
511	} else {
512		if (!(rs5c372->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_XSTP))
513			return ret;
514		rs5c372->regs[RS5C_REG_CTRL2] &= ~RS5C_CTRL2_XSTP;
515	}
516
517	addr   = RS5C_ADDR(RS5C_REG_CTRL1);
518	buf[0] = rs5c372->regs[RS5C_REG_CTRL1];
519	buf[1] = rs5c372->regs[RS5C_REG_CTRL2];
520
521	/* use 24hr mode */
522	switch (rs5c372->type) {
523	case rtc_rs5c372a:
524	case rtc_rs5c372b:
525		buf[1] |= RS5C372_CTRL2_24;
526		rs5c372->time24 = 1;
527		break;
528	case rtc_r2025sd:
 
529	case rtc_rv5c386:
530	case rtc_rv5c387a:
531		buf[0] |= RV5C387_CTRL1_24;
532		rs5c372->time24 = 1;
533		break;
534	default:
535		/* impossible */
536		break;
537	}
538
539	for (i = 0; i < sizeof(buf); i++) {
540		addr = RS5C_ADDR(RS5C_REG_CTRL1 + i);
541		ret = i2c_smbus_write_byte_data(rs5c372->client, addr, buf[i]);
542		if (unlikely(ret < 0))
543			return ret;
544	}
545
546	rs5c372->regs[RS5C_REG_CTRL1] = buf[0];
547	rs5c372->regs[RS5C_REG_CTRL2] = buf[1];
548
549	return 0;
550}
551
552static int rs5c372_probe(struct i2c_client *client,
553			 const struct i2c_device_id *id)
554{
555	int err = 0;
556	int smbus_mode = 0;
557	struct rs5c372 *rs5c372;
558	struct rtc_time tm;
559
560	dev_dbg(&client->dev, "%s\n", __func__);
561
562	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
563			I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK)) {
564		/*
565		 * If we don't have any master mode adapter, try breaking
566		 * it down in to the barest of capabilities.
567		 */
568		if (i2c_check_functionality(client->adapter,
569				I2C_FUNC_SMBUS_BYTE_DATA |
570				I2C_FUNC_SMBUS_I2C_BLOCK))
571			smbus_mode = 1;
572		else {
573			/* Still no good, give up */
574			err = -ENODEV;
575			goto exit;
576		}
577	}
578
579	if (!(rs5c372 = kzalloc(sizeof(struct rs5c372), GFP_KERNEL))) {
 
 
580		err = -ENOMEM;
581		goto exit;
582	}
583
584	rs5c372->client = client;
585	i2c_set_clientdata(client, rs5c372);
586	rs5c372->type = id->driver_data;
587
588	/* we read registers 0x0f then 0x00-0x0f; skip the first one */
589	rs5c372->regs = &rs5c372->buf[1];
590	rs5c372->smbus = smbus_mode;
591
592	err = rs5c_get_regs(rs5c372);
593	if (err < 0)
594		goto exit_kfree;
595
596	/* clock may be set for am/pm or 24 hr time */
597	switch (rs5c372->type) {
598	case rtc_rs5c372a:
599	case rtc_rs5c372b:
600		/* alarm uses ALARM_A; and nINTRA on 372a, nINTR on 372b.
601		 * so does periodic irq, except some 327a modes.
602		 */
603		if (rs5c372->regs[RS5C_REG_CTRL2] & RS5C372_CTRL2_24)
604			rs5c372->time24 = 1;
605		break;
606	case rtc_r2025sd:
 
607	case rtc_rv5c386:
608	case rtc_rv5c387a:
609		if (rs5c372->regs[RS5C_REG_CTRL1] & RV5C387_CTRL1_24)
610			rs5c372->time24 = 1;
611		/* alarm uses ALARM_W; and nINTRB for alarm and periodic
612		 * irq, on both 386 and 387
613		 */
614		break;
615	default:
616		dev_err(&client->dev, "unknown RTC type\n");
617		goto exit_kfree;
618	}
619
620	/* if the oscillator lost power and no other software (like
621	 * the bootloader) set it up, do it here.
622	 *
623	 * The R2025S/D does this a little differently than the other
624	 * parts, so we special case that..
625	 */
626	err = rs5c_oscillator_setup(rs5c372);
627	if (unlikely(err < 0)) {
628		dev_err(&client->dev, "setup error\n");
629		goto exit_kfree;
630	}
631
632	if (rs5c372_get_datetime(client, &tm) < 0)
633		dev_warn(&client->dev, "clock needs to be set\n");
634
635	dev_info(&client->dev, "%s found, %s, driver version " DRV_VERSION "\n",
636			({ char *s; switch (rs5c372->type) {
637			case rtc_r2025sd:	s = "r2025sd"; 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
649	rs5c372->rtc = rtc_device_register(rs5c372_driver.driver.name,
650				&client->dev, &rs5c372_rtc_ops, THIS_MODULE);
651
652	if (IS_ERR(rs5c372->rtc)) {
653		err = PTR_ERR(rs5c372->rtc);
654		goto exit_kfree;
655	}
656
657	err = rs5c_sysfs_register(&client->dev);
658	if (err)
659		goto exit_devreg;
660
661	return 0;
662
663exit_devreg:
664	rtc_device_unregister(rs5c372->rtc);
665
666exit_kfree:
667	kfree(rs5c372);
668
669exit:
670	return err;
671}
672
673static int rs5c372_remove(struct i2c_client *client)
674{
675	struct rs5c372 *rs5c372 = i2c_get_clientdata(client);
676
677	rtc_device_unregister(rs5c372->rtc);
678	rs5c_sysfs_unregister(&client->dev);
679	kfree(rs5c372);
680	return 0;
681}
682
683static struct i2c_driver rs5c372_driver = {
684	.driver		= {
685		.name	= "rtc-rs5c372",
686	},
687	.probe		= rs5c372_probe,
688	.remove		= rs5c372_remove,
689	.id_table	= rs5c372_id,
690};
691
692module_i2c_driver(rs5c372_driver);
693
694MODULE_AUTHOR(
695		"Pavel Mironchik <pmironchik@optifacio.net>, "
696		"Alessandro Zummo <a.zummo@towertech.it>, "
697		"Paul Mundt <lethal@linux-sh.org>");
698MODULE_DESCRIPTION("Ricoh RS5C372 RTC driver");
699MODULE_LICENSE("GPL");
700MODULE_VERSION(DRV_VERSION);
v4.6
  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);