xref: /openbmc/linux/drivers/rtc/rtc-fm3130.c (revision 0abc9201)
1 /*
2  * rtc-fm3130.c - RTC driver for Ramtron FM3130 I2C chip.
3  *
4  *  Copyright (C) 2008 Sergey Lapin
5  *  Based on ds1307 driver by James Chapman and David Brownell
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/module.h>
13 #include <linux/i2c.h>
14 #include <linux/rtc.h>
15 #include <linux/bcd.h>
16 #include <linux/slab.h>
17 
18 #define FM3130_RTC_CONTROL	(0x0)
19 #define FM3130_CAL_CONTROL	(0x1)
20 #define FM3130_RTC_SECONDS	(0x2)
21 #define FM3130_RTC_MINUTES	(0x3)
22 #define FM3130_RTC_HOURS	(0x4)
23 #define FM3130_RTC_DAY		(0x5)
24 #define FM3130_RTC_DATE		(0x6)
25 #define FM3130_RTC_MONTHS	(0x7)
26 #define FM3130_RTC_YEARS	(0x8)
27 
28 #define FM3130_ALARM_SECONDS	(0x9)
29 #define FM3130_ALARM_MINUTES	(0xa)
30 #define FM3130_ALARM_HOURS	(0xb)
31 #define FM3130_ALARM_DATE	(0xc)
32 #define FM3130_ALARM_MONTHS	(0xd)
33 #define FM3130_ALARM_WP_CONTROL	(0xe)
34 
35 #define FM3130_CAL_CONTROL_BIT_nOSCEN (1 << 7) /* Osciallator enabled */
36 #define FM3130_RTC_CONTROL_BIT_LB (1 << 7) /* Low battery */
37 #define FM3130_RTC_CONTROL_BIT_AF (1 << 6) /* Alarm flag */
38 #define FM3130_RTC_CONTROL_BIT_CF (1 << 5) /* Century overflow */
39 #define FM3130_RTC_CONTROL_BIT_POR (1 << 4) /* Power on reset */
40 #define FM3130_RTC_CONTROL_BIT_AEN (1 << 3) /* Alarm enable */
41 #define FM3130_RTC_CONTROL_BIT_CAL (1 << 2) /* Calibration mode */
42 #define FM3130_RTC_CONTROL_BIT_WRITE (1 << 1) /* W=1 -> write mode W=0 normal */
43 #define FM3130_RTC_CONTROL_BIT_READ (1 << 0) /* R=1 -> read mode R=0 normal */
44 
45 #define FM3130_CLOCK_REGS 7
46 #define FM3130_ALARM_REGS 5
47 
48 struct fm3130 {
49 	u8			reg_addr_time;
50 	u8 			reg_addr_alarm;
51 	u8			regs[15];
52 	struct i2c_msg		msg[4];
53 	struct i2c_client	*client;
54 	struct rtc_device	*rtc;
55 	int			alarm_valid;
56 	int			data_valid;
57 };
58 static const struct i2c_device_id fm3130_id[] = {
59 	{ "fm3130", 0 },
60 	{ }
61 };
62 MODULE_DEVICE_TABLE(i2c, fm3130_id);
63 
64 #define FM3130_MODE_NORMAL		0
65 #define FM3130_MODE_WRITE		1
66 #define FM3130_MODE_READ		2
67 
68 static void fm3130_rtc_mode(struct device *dev, int mode)
69 {
70 	struct fm3130 *fm3130 = dev_get_drvdata(dev);
71 
72 	fm3130->regs[FM3130_RTC_CONTROL] =
73 		i2c_smbus_read_byte_data(fm3130->client, FM3130_RTC_CONTROL);
74 	switch (mode) {
75 	case FM3130_MODE_NORMAL:
76 		fm3130->regs[FM3130_RTC_CONTROL] &=
77 			~(FM3130_RTC_CONTROL_BIT_WRITE |
78 			FM3130_RTC_CONTROL_BIT_READ);
79 		break;
80 	case FM3130_MODE_WRITE:
81 		fm3130->regs[FM3130_RTC_CONTROL] |= FM3130_RTC_CONTROL_BIT_WRITE;
82 		break;
83 	case FM3130_MODE_READ:
84 		fm3130->regs[FM3130_RTC_CONTROL] |= FM3130_RTC_CONTROL_BIT_READ;
85 		break;
86 	default:
87 		dev_dbg(dev, "invalid mode %d\n", mode);
88 		break;
89 	}
90 
91 	i2c_smbus_write_byte_data(fm3130->client,
92 		 FM3130_RTC_CONTROL, fm3130->regs[FM3130_RTC_CONTROL]);
93 }
94 
95 static int fm3130_get_time(struct device *dev, struct rtc_time *t)
96 {
97 	struct fm3130 *fm3130 = dev_get_drvdata(dev);
98 	int		tmp;
99 
100 	if (!fm3130->data_valid) {
101 		/* We have invalid data in RTC, probably due
102 		to battery faults or other problems. Return EIO
103 		for now, it will allow us to set data later instead
104 		of error during probing which disables device */
105 		return -EIO;
106 	}
107 	fm3130_rtc_mode(dev, FM3130_MODE_READ);
108 
109 	/* read the RTC date and time registers all at once */
110 	tmp = i2c_transfer(to_i2c_adapter(fm3130->client->dev.parent),
111 			fm3130->msg, 2);
112 	if (tmp != 2) {
113 		dev_err(dev, "%s error %d\n", "read", tmp);
114 		return -EIO;
115 	}
116 
117 	fm3130_rtc_mode(dev, FM3130_MODE_NORMAL);
118 
119 	dev_dbg(dev, "%s: %02x %02x %02x %02x %02x %02x %02x %02x"
120 			"%02x %02x %02x %02x %02x %02x %02x\n",
121 			"read",
122 			fm3130->regs[0], fm3130->regs[1],
123 			fm3130->regs[2], fm3130->regs[3],
124 			fm3130->regs[4], fm3130->regs[5],
125 			fm3130->regs[6], fm3130->regs[7],
126 			fm3130->regs[8], fm3130->regs[9],
127 			fm3130->regs[0xa], fm3130->regs[0xb],
128 			fm3130->regs[0xc], fm3130->regs[0xd],
129 			fm3130->regs[0xe]);
130 
131 	t->tm_sec = bcd2bin(fm3130->regs[FM3130_RTC_SECONDS] & 0x7f);
132 	t->tm_min = bcd2bin(fm3130->regs[FM3130_RTC_MINUTES] & 0x7f);
133 	tmp = fm3130->regs[FM3130_RTC_HOURS] & 0x3f;
134 	t->tm_hour = bcd2bin(tmp);
135 	t->tm_wday = bcd2bin(fm3130->regs[FM3130_RTC_DAY] & 0x07) - 1;
136 	t->tm_mday = bcd2bin(fm3130->regs[FM3130_RTC_DATE] & 0x3f);
137 	tmp = fm3130->regs[FM3130_RTC_MONTHS] & 0x1f;
138 	t->tm_mon = bcd2bin(tmp) - 1;
139 
140 	/* assume 20YY not 19YY, and ignore CF bit */
141 	t->tm_year = bcd2bin(fm3130->regs[FM3130_RTC_YEARS]) + 100;
142 
143 	dev_dbg(dev, "%s secs=%d, mins=%d, "
144 		"hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
145 		"read", t->tm_sec, t->tm_min,
146 		t->tm_hour, t->tm_mday,
147 		t->tm_mon, t->tm_year, t->tm_wday);
148 
149 	/* initial clock setting can be undefined */
150 	return rtc_valid_tm(t);
151 }
152 
153 
154 static int fm3130_set_time(struct device *dev, struct rtc_time *t)
155 {
156 	struct fm3130 *fm3130 = dev_get_drvdata(dev);
157 	int		tmp, i;
158 	u8		*buf = fm3130->regs;
159 
160 	dev_dbg(dev, "%s secs=%d, mins=%d, "
161 		"hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
162 		"write", t->tm_sec, t->tm_min,
163 		t->tm_hour, t->tm_mday,
164 		t->tm_mon, t->tm_year, t->tm_wday);
165 
166 	/* first register addr */
167 	buf[FM3130_RTC_SECONDS] = bin2bcd(t->tm_sec);
168 	buf[FM3130_RTC_MINUTES] = bin2bcd(t->tm_min);
169 	buf[FM3130_RTC_HOURS] = bin2bcd(t->tm_hour);
170 	buf[FM3130_RTC_DAY] = bin2bcd(t->tm_wday + 1);
171 	buf[FM3130_RTC_DATE] = bin2bcd(t->tm_mday);
172 	buf[FM3130_RTC_MONTHS] = bin2bcd(t->tm_mon + 1);
173 
174 	/* assume 20YY not 19YY */
175 	tmp = t->tm_year - 100;
176 	buf[FM3130_RTC_YEARS] = bin2bcd(tmp);
177 
178 	dev_dbg(dev, "%s: %02x %02x %02x %02x %02x %02x %02x"
179 		"%02x %02x %02x %02x %02x %02x %02x %02x\n",
180 		"write", buf[0], buf[1], buf[2], buf[3],
181 		buf[4], buf[5], buf[6], buf[7],
182 		buf[8], buf[9], buf[0xa], buf[0xb],
183 		buf[0xc], buf[0xd], buf[0xe]);
184 
185 	fm3130_rtc_mode(dev, FM3130_MODE_WRITE);
186 
187 	/* Writing time registers, we don't support multibyte transfers */
188 	for (i = 0; i < FM3130_CLOCK_REGS; i++) {
189 		i2c_smbus_write_byte_data(fm3130->client,
190 					FM3130_RTC_SECONDS + i,
191 					fm3130->regs[FM3130_RTC_SECONDS + i]);
192 	}
193 
194 	fm3130_rtc_mode(dev, FM3130_MODE_NORMAL);
195 
196 	/* We assume here that data are valid once written */
197 	if (!fm3130->data_valid)
198 		fm3130->data_valid = 1;
199 	return 0;
200 }
201 
202 static int fm3130_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
203 {
204 	struct fm3130 *fm3130 = dev_get_drvdata(dev);
205 	int tmp;
206 	struct rtc_time *tm = &alrm->time;
207 
208 	if (!fm3130->alarm_valid) {
209 		/*
210 		 * We have invalid alarm in RTC, probably due to battery faults
211 		 * or other problems. Return EIO for now, it will allow us to
212 		 * set alarm value later instead of error during probing which
213 		 * disables device
214 		 */
215 		return -EIO;
216 	}
217 
218 	/* read the RTC alarm registers all at once */
219 	tmp = i2c_transfer(to_i2c_adapter(fm3130->client->dev.parent),
220 			&fm3130->msg[2], 2);
221 	if (tmp != 2) {
222 		dev_err(dev, "%s error %d\n", "read", tmp);
223 		return -EIO;
224 	}
225 	dev_dbg(dev, "alarm read %02x %02x %02x %02x %02x\n",
226 			fm3130->regs[FM3130_ALARM_SECONDS],
227 			fm3130->regs[FM3130_ALARM_MINUTES],
228 			fm3130->regs[FM3130_ALARM_HOURS],
229 			fm3130->regs[FM3130_ALARM_DATE],
230 			fm3130->regs[FM3130_ALARM_MONTHS]);
231 
232 	tm->tm_sec	= bcd2bin(fm3130->regs[FM3130_ALARM_SECONDS] & 0x7F);
233 	tm->tm_min	= bcd2bin(fm3130->regs[FM3130_ALARM_MINUTES] & 0x7F);
234 	tm->tm_hour	= bcd2bin(fm3130->regs[FM3130_ALARM_HOURS] & 0x3F);
235 	tm->tm_mday	= bcd2bin(fm3130->regs[FM3130_ALARM_DATE] & 0x3F);
236 	tm->tm_mon	= bcd2bin(fm3130->regs[FM3130_ALARM_MONTHS] & 0x1F);
237 
238 	if (tm->tm_mon > 0)
239 		tm->tm_mon -= 1; /* RTC is 1-12, tm_mon is 0-11 */
240 
241 	dev_dbg(dev, "%s secs=%d, mins=%d, "
242 		"hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
243 		"read alarm", tm->tm_sec, tm->tm_min,
244 		tm->tm_hour, tm->tm_mday,
245 		tm->tm_mon, tm->tm_year, tm->tm_wday);
246 
247 	/* check if alarm enabled */
248 	fm3130->regs[FM3130_RTC_CONTROL] =
249 		i2c_smbus_read_byte_data(fm3130->client, FM3130_RTC_CONTROL);
250 
251 	if ((fm3130->regs[FM3130_RTC_CONTROL] & FM3130_RTC_CONTROL_BIT_AEN) &&
252 		(~fm3130->regs[FM3130_RTC_CONTROL] &
253 			FM3130_RTC_CONTROL_BIT_CAL)) {
254 		alrm->enabled = 1;
255 	}
256 
257 	return 0;
258 }
259 
260 static int fm3130_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
261 {
262 	struct fm3130 *fm3130 = dev_get_drvdata(dev);
263 	struct rtc_time *tm = &alrm->time;
264 	int i;
265 
266 	dev_dbg(dev, "%s secs=%d, mins=%d, "
267 		"hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
268 		"write alarm", tm->tm_sec, tm->tm_min,
269 		tm->tm_hour, tm->tm_mday,
270 		tm->tm_mon, tm->tm_year, tm->tm_wday);
271 
272 	fm3130->regs[FM3130_ALARM_SECONDS] =
273 		(tm->tm_sec != -1) ? bin2bcd(tm->tm_sec) : 0x80;
274 
275 	fm3130->regs[FM3130_ALARM_MINUTES] =
276 		(tm->tm_min != -1) ? bin2bcd(tm->tm_min) : 0x80;
277 
278 	fm3130->regs[FM3130_ALARM_HOURS] =
279 		(tm->tm_hour != -1) ? bin2bcd(tm->tm_hour) : 0x80;
280 
281 	fm3130->regs[FM3130_ALARM_DATE] =
282 		(tm->tm_mday != -1) ? bin2bcd(tm->tm_mday) : 0x80;
283 
284 	fm3130->regs[FM3130_ALARM_MONTHS] =
285 		(tm->tm_mon != -1) ? bin2bcd(tm->tm_mon + 1) : 0x80;
286 
287 	dev_dbg(dev, "alarm write %02x %02x %02x %02x %02x\n",
288 			fm3130->regs[FM3130_ALARM_SECONDS],
289 			fm3130->regs[FM3130_ALARM_MINUTES],
290 			fm3130->regs[FM3130_ALARM_HOURS],
291 			fm3130->regs[FM3130_ALARM_DATE],
292 			fm3130->regs[FM3130_ALARM_MONTHS]);
293 	/* Writing time registers, we don't support multibyte transfers */
294 	for (i = 0; i < FM3130_ALARM_REGS; i++) {
295 		i2c_smbus_write_byte_data(fm3130->client,
296 					FM3130_ALARM_SECONDS + i,
297 					fm3130->regs[FM3130_ALARM_SECONDS + i]);
298 	}
299 	fm3130->regs[FM3130_RTC_CONTROL] =
300 		i2c_smbus_read_byte_data(fm3130->client, FM3130_RTC_CONTROL);
301 
302 	/* enable or disable alarm */
303 	if (alrm->enabled) {
304 		i2c_smbus_write_byte_data(fm3130->client, FM3130_RTC_CONTROL,
305 			(fm3130->regs[FM3130_RTC_CONTROL] &
306 				~(FM3130_RTC_CONTROL_BIT_CAL)) |
307 					FM3130_RTC_CONTROL_BIT_AEN);
308 	} else {
309 		i2c_smbus_write_byte_data(fm3130->client, FM3130_RTC_CONTROL,
310 			fm3130->regs[FM3130_RTC_CONTROL] &
311 				~(FM3130_RTC_CONTROL_BIT_CAL) &
312 					~(FM3130_RTC_CONTROL_BIT_AEN));
313 	}
314 
315 	/* We assume here that data is valid once written */
316 	if (!fm3130->alarm_valid)
317 		fm3130->alarm_valid = 1;
318 
319 	return 0;
320 }
321 
322 static int fm3130_alarm_irq_enable(struct device *dev, unsigned int enabled)
323 {
324 	struct fm3130 *fm3130 = dev_get_drvdata(dev);
325 	int ret = 0;
326 
327 	fm3130->regs[FM3130_RTC_CONTROL] =
328 		i2c_smbus_read_byte_data(fm3130->client, FM3130_RTC_CONTROL);
329 
330 	dev_dbg(dev, "alarm_irq_enable: enable=%d, FM3130_RTC_CONTROL=%02x\n",
331 		enabled, fm3130->regs[FM3130_RTC_CONTROL]);
332 
333 	switch (enabled) {
334 	case 0:		/* alarm off */
335 		ret = i2c_smbus_write_byte_data(fm3130->client,
336 			FM3130_RTC_CONTROL, fm3130->regs[FM3130_RTC_CONTROL] &
337 				~(FM3130_RTC_CONTROL_BIT_CAL) &
338 					~(FM3130_RTC_CONTROL_BIT_AEN));
339 		break;
340 	case 1:		/* alarm on */
341 		ret = i2c_smbus_write_byte_data(fm3130->client,
342 			FM3130_RTC_CONTROL, (fm3130->regs[FM3130_RTC_CONTROL] &
343 				~(FM3130_RTC_CONTROL_BIT_CAL)) |
344 					FM3130_RTC_CONTROL_BIT_AEN);
345 		break;
346 	default:
347 		ret = -EINVAL;
348 		break;
349 	}
350 
351 	return ret;
352 }
353 
354 static const struct rtc_class_ops fm3130_rtc_ops = {
355 	.read_time	= fm3130_get_time,
356 	.set_time	= fm3130_set_time,
357 	.read_alarm	= fm3130_read_alarm,
358 	.set_alarm	= fm3130_set_alarm,
359 	.alarm_irq_enable = fm3130_alarm_irq_enable,
360 };
361 
362 static struct i2c_driver fm3130_driver;
363 
364 static int __devinit fm3130_probe(struct i2c_client *client,
365 				  const struct i2c_device_id *id)
366 {
367 	struct fm3130		*fm3130;
368 	int			err = -ENODEV;
369 	int			tmp;
370 	struct i2c_adapter	*adapter = to_i2c_adapter(client->dev.parent);
371 
372 	if (!i2c_check_functionality(adapter,
373 			I2C_FUNC_I2C | I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
374 		return -EIO;
375 
376 	fm3130 = kzalloc(sizeof(struct fm3130), GFP_KERNEL);
377 
378 	if (!fm3130)
379 		return -ENOMEM;
380 
381 	fm3130->client = client;
382 	i2c_set_clientdata(client, fm3130);
383 	fm3130->reg_addr_time = FM3130_RTC_SECONDS;
384 	fm3130->reg_addr_alarm = FM3130_ALARM_SECONDS;
385 
386 	/* Messages to read time */
387 	fm3130->msg[0].addr = client->addr;
388 	fm3130->msg[0].flags = 0;
389 	fm3130->msg[0].len = 1;
390 	fm3130->msg[0].buf = &fm3130->reg_addr_time;
391 
392 	fm3130->msg[1].addr = client->addr;
393 	fm3130->msg[1].flags = I2C_M_RD;
394 	fm3130->msg[1].len = FM3130_CLOCK_REGS;
395 	fm3130->msg[1].buf = &fm3130->regs[FM3130_RTC_SECONDS];
396 
397 	/* Messages to read alarm */
398 	fm3130->msg[2].addr = client->addr;
399 	fm3130->msg[2].flags = 0;
400 	fm3130->msg[2].len = 1;
401 	fm3130->msg[2].buf = &fm3130->reg_addr_alarm;
402 
403 	fm3130->msg[3].addr = client->addr;
404 	fm3130->msg[3].flags = I2C_M_RD;
405 	fm3130->msg[3].len = FM3130_ALARM_REGS;
406 	fm3130->msg[3].buf = &fm3130->regs[FM3130_ALARM_SECONDS];
407 
408 	fm3130->alarm_valid = 0;
409 	fm3130->data_valid = 0;
410 
411 	tmp = i2c_transfer(adapter, fm3130->msg, 4);
412 	if (tmp != 4) {
413 		pr_debug("read error %d\n", tmp);
414 		err = -EIO;
415 		goto exit_free;
416 	}
417 
418 	fm3130->regs[FM3130_RTC_CONTROL] =
419 		i2c_smbus_read_byte_data(client, FM3130_RTC_CONTROL);
420 	fm3130->regs[FM3130_CAL_CONTROL] =
421 		i2c_smbus_read_byte_data(client, FM3130_CAL_CONTROL);
422 
423 	/* Disabling calibration mode */
424 	if (fm3130->regs[FM3130_RTC_CONTROL] & FM3130_RTC_CONTROL_BIT_CAL) {
425 		i2c_smbus_write_byte_data(client, FM3130_RTC_CONTROL,
426 			fm3130->regs[FM3130_RTC_CONTROL] &
427 				~(FM3130_RTC_CONTROL_BIT_CAL));
428 		dev_warn(&client->dev, "Disabling calibration mode!\n");
429 	}
430 
431 	/* Disabling read and write modes */
432 	if (fm3130->regs[FM3130_RTC_CONTROL] & FM3130_RTC_CONTROL_BIT_WRITE ||
433 	    fm3130->regs[FM3130_RTC_CONTROL] & FM3130_RTC_CONTROL_BIT_READ) {
434 		i2c_smbus_write_byte_data(client, FM3130_RTC_CONTROL,
435 			fm3130->regs[FM3130_RTC_CONTROL] &
436 				~(FM3130_RTC_CONTROL_BIT_READ |
437 					FM3130_RTC_CONTROL_BIT_WRITE));
438 		dev_warn(&client->dev, "Disabling READ or WRITE mode!\n");
439 	}
440 
441 	/* oscillator off?  turn it on, so clock can tick. */
442 	if (fm3130->regs[FM3130_CAL_CONTROL] & FM3130_CAL_CONTROL_BIT_nOSCEN)
443 		i2c_smbus_write_byte_data(client, FM3130_CAL_CONTROL,
444 			fm3130->regs[FM3130_CAL_CONTROL] &
445 				~(FM3130_CAL_CONTROL_BIT_nOSCEN));
446 
447 	/* low battery?  clear flag, and warn */
448 	if (fm3130->regs[FM3130_RTC_CONTROL] & FM3130_RTC_CONTROL_BIT_LB) {
449 		i2c_smbus_write_byte_data(client, FM3130_RTC_CONTROL,
450 			fm3130->regs[FM3130_RTC_CONTROL] &
451 				~(FM3130_RTC_CONTROL_BIT_LB));
452 		dev_warn(&client->dev, "Low battery!\n");
453 	}
454 
455 	/* check if Power On Reset bit is set */
456 	if (fm3130->regs[FM3130_RTC_CONTROL] & FM3130_RTC_CONTROL_BIT_POR) {
457 		i2c_smbus_write_byte_data(client, FM3130_RTC_CONTROL,
458 			fm3130->regs[FM3130_RTC_CONTROL] &
459 				~FM3130_RTC_CONTROL_BIT_POR);
460 		dev_dbg(&client->dev, "POR bit is set\n");
461 	}
462 	/* ACS is controlled by alarm */
463 	i2c_smbus_write_byte_data(client, FM3130_ALARM_WP_CONTROL, 0x80);
464 
465 	/* alarm registers sanity check */
466 	tmp = bcd2bin(fm3130->regs[FM3130_RTC_SECONDS] & 0x7f);
467 	if (tmp > 59)
468 		goto bad_alarm;
469 
470 	tmp = bcd2bin(fm3130->regs[FM3130_RTC_MINUTES] & 0x7f);
471 	if (tmp > 59)
472 		goto bad_alarm;
473 
474 	tmp = bcd2bin(fm3130->regs[FM3130_RTC_HOURS] & 0x3f);
475 	if (tmp > 23)
476 		goto bad_alarm;
477 
478 	tmp = bcd2bin(fm3130->regs[FM3130_RTC_DATE] & 0x3f);
479 	if (tmp == 0 || tmp > 31)
480 		goto bad_alarm;
481 
482 	tmp = bcd2bin(fm3130->regs[FM3130_RTC_MONTHS] & 0x1f);
483 	if (tmp == 0 || tmp > 12)
484 		goto bad_alarm;
485 
486 	fm3130->alarm_valid = 1;
487 
488 bad_alarm:
489 
490 	/* clock registers sanity chek */
491 	tmp = bcd2bin(fm3130->regs[FM3130_RTC_SECONDS] & 0x7f);
492 	if (tmp > 59)
493 		goto bad_clock;
494 
495 	tmp = bcd2bin(fm3130->regs[FM3130_RTC_MINUTES] & 0x7f);
496 	if (tmp > 59)
497 		goto bad_clock;
498 
499 	tmp = bcd2bin(fm3130->regs[FM3130_RTC_HOURS] & 0x3f);
500 	if (tmp > 23)
501 		goto bad_clock;
502 
503 	tmp = bcd2bin(fm3130->regs[FM3130_RTC_DAY] & 0x7);
504 	if (tmp == 0 || tmp > 7)
505 		goto bad_clock;
506 
507 	tmp = bcd2bin(fm3130->regs[FM3130_RTC_DATE] & 0x3f);
508 	if (tmp == 0 || tmp > 31)
509 		goto bad_clock;
510 
511 	tmp = bcd2bin(fm3130->regs[FM3130_RTC_MONTHS] & 0x1f);
512 	if (tmp == 0 || tmp > 12)
513 		goto bad_clock;
514 
515 	fm3130->data_valid = 1;
516 
517 bad_clock:
518 
519 	if (!fm3130->data_valid || !fm3130->alarm_valid)
520 		dev_dbg(&client->dev,
521 				"%s: %02x %02x %02x %02x %02x %02x %02x %02x"
522 				"%02x %02x %02x %02x %02x %02x %02x\n",
523 			"bogus registers",
524 			fm3130->regs[0], fm3130->regs[1],
525 			fm3130->regs[2], fm3130->regs[3],
526 			fm3130->regs[4], fm3130->regs[5],
527 			fm3130->regs[6], fm3130->regs[7],
528 			fm3130->regs[8], fm3130->regs[9],
529 			fm3130->regs[0xa], fm3130->regs[0xb],
530 			fm3130->regs[0xc], fm3130->regs[0xd],
531 			fm3130->regs[0xe]);
532 
533 	/* We won't bail out here because we just got invalid data.
534 	   Time setting from u-boot doesn't work anyway */
535 	fm3130->rtc = rtc_device_register(client->name, &client->dev,
536 				&fm3130_rtc_ops, THIS_MODULE);
537 	if (IS_ERR(fm3130->rtc)) {
538 		err = PTR_ERR(fm3130->rtc);
539 		dev_err(&client->dev,
540 			"unable to register the class device\n");
541 		goto exit_free;
542 	}
543 	return 0;
544 exit_free:
545 	kfree(fm3130);
546 	return err;
547 }
548 
549 static int __devexit fm3130_remove(struct i2c_client *client)
550 {
551 	struct fm3130 *fm3130 = i2c_get_clientdata(client);
552 
553 	rtc_device_unregister(fm3130->rtc);
554 	kfree(fm3130);
555 	return 0;
556 }
557 
558 static struct i2c_driver fm3130_driver = {
559 	.driver = {
560 		.name	= "rtc-fm3130",
561 		.owner	= THIS_MODULE,
562 	},
563 	.probe		= fm3130_probe,
564 	.remove		= __devexit_p(fm3130_remove),
565 	.id_table	= fm3130_id,
566 };
567 
568 module_i2c_driver(fm3130_driver);
569 
570 MODULE_DESCRIPTION("RTC driver for FM3130");
571 MODULE_AUTHOR("Sergey Lapin <slapin@ossfans.org>");
572 MODULE_LICENSE("GPL");
573 
574