xref: /openbmc/linux/drivers/rtc/rtc-rx8025.c (revision b6dcefde)
1 /*
2  * Driver for Epson's RTC module RX-8025 SA/NB
3  *
4  * Copyright (C) 2009 Wolfgang Grandegger <wg@grandegger.com>
5  *
6  * Copyright (C) 2005 by Digi International Inc.
7  * All rights reserved.
8  *
9  * Modified by fengjh at rising.com.cn
10  * <http://lists.lm-sensors.org/mailman/listinfo/lm-sensors>
11  * 2006.11
12  *
13  * Code cleanup by Sergei Poselenov, <sposelenov@emcraft.com>
14  * Converted to new style by Wolfgang Grandegger <wg@grandegger.com>
15  * Alarm and periodic interrupt added by Dmitry Rakhchev <rda@emcraft.com>
16  *
17  * This program is free software; you can redistribute it and/or
18  * modify it under the terms of the GNU General Public License
19  * version 2 as published by the Free Software Foundation.
20  */
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/init.h>
24 #include <linux/bcd.h>
25 #include <linux/i2c.h>
26 #include <linux/list.h>
27 #include <linux/rtc.h>
28 
29 /* Register definitions */
30 #define RX8025_REG_SEC		0x00
31 #define RX8025_REG_MIN		0x01
32 #define RX8025_REG_HOUR		0x02
33 #define RX8025_REG_WDAY		0x03
34 #define RX8025_REG_MDAY		0x04
35 #define RX8025_REG_MONTH	0x05
36 #define RX8025_REG_YEAR		0x06
37 #define RX8025_REG_DIGOFF	0x07
38 #define RX8025_REG_ALWMIN	0x08
39 #define RX8025_REG_ALWHOUR	0x09
40 #define RX8025_REG_ALWWDAY	0x0a
41 #define RX8025_REG_ALDMIN	0x0b
42 #define RX8025_REG_ALDHOUR	0x0c
43 /* 0x0d is reserved */
44 #define RX8025_REG_CTRL1	0x0e
45 #define RX8025_REG_CTRL2	0x0f
46 
47 #define RX8025_BIT_CTRL1_CT	(7 << 0)
48 /* 1 Hz periodic level irq */
49 #define RX8025_BIT_CTRL1_CT_1HZ	4
50 #define RX8025_BIT_CTRL1_TEST	(1 << 3)
51 #define RX8025_BIT_CTRL1_1224	(1 << 5)
52 #define RX8025_BIT_CTRL1_DALE	(1 << 6)
53 #define RX8025_BIT_CTRL1_WALE	(1 << 7)
54 
55 #define RX8025_BIT_CTRL2_DAFG	(1 << 0)
56 #define RX8025_BIT_CTRL2_WAFG	(1 << 1)
57 #define RX8025_BIT_CTRL2_CTFG	(1 << 2)
58 #define RX8025_BIT_CTRL2_PON	(1 << 4)
59 #define RX8025_BIT_CTRL2_XST	(1 << 5)
60 #define RX8025_BIT_CTRL2_VDET	(1 << 6)
61 
62 /* Clock precision adjustment */
63 #define RX8025_ADJ_RESOLUTION	3050 /* in ppb */
64 #define RX8025_ADJ_DATA_MAX	62
65 #define RX8025_ADJ_DATA_MIN	-62
66 
67 static const struct i2c_device_id rx8025_id[] = {
68 	{ "rx8025", 0 },
69 	{ }
70 };
71 MODULE_DEVICE_TABLE(i2c, rx8025_id);
72 
73 struct rx8025_data {
74 	struct i2c_client *client;
75 	struct rtc_device *rtc;
76 	struct work_struct work;
77 	u8 ctrl1;
78 	unsigned exiting:1;
79 };
80 
81 static int rx8025_read_reg(struct i2c_client *client, int number, u8 *value)
82 {
83 	int ret = i2c_smbus_read_byte_data(client, (number << 4) | 0x08);
84 
85 	if (ret < 0) {
86 		dev_err(&client->dev, "Unable to read register #%d\n", number);
87 		return ret;
88 	}
89 
90 	*value = ret;
91 	return 0;
92 }
93 
94 static int rx8025_read_regs(struct i2c_client *client,
95 			    int number, u8 length, u8 *values)
96 {
97 	int ret = i2c_smbus_read_i2c_block_data(client, (number << 4) | 0x08,
98 						length, values);
99 
100 	if (ret != length) {
101 		dev_err(&client->dev, "Unable to read registers #%d..#%d\n",
102 			number, number + length - 1);
103 		return ret < 0 ? ret : -EIO;
104 	}
105 
106 	return 0;
107 }
108 
109 static int rx8025_write_reg(struct i2c_client *client, int number, u8 value)
110 {
111 	int ret = i2c_smbus_write_byte_data(client, number << 4, value);
112 
113 	if (ret)
114 		dev_err(&client->dev, "Unable to write register #%d\n",
115 			number);
116 
117 	return ret;
118 }
119 
120 static int rx8025_write_regs(struct i2c_client *client,
121 			     int number, u8 length, u8 *values)
122 {
123 	int ret = i2c_smbus_write_i2c_block_data(client, (number << 4) | 0x08,
124 						 length, values);
125 
126 	if (ret)
127 		dev_err(&client->dev, "Unable to write registers #%d..#%d\n",
128 			number, number + length - 1);
129 
130 	return ret;
131 }
132 
133 static irqreturn_t rx8025_irq(int irq, void *dev_id)
134 {
135 	struct i2c_client *client = dev_id;
136 	struct rx8025_data *rx8025 = i2c_get_clientdata(client);
137 
138 	disable_irq_nosync(irq);
139 	schedule_work(&rx8025->work);
140 	return IRQ_HANDLED;
141 }
142 
143 static void rx8025_work(struct work_struct *work)
144 {
145 	struct rx8025_data *rx8025 = container_of(work, struct rx8025_data,
146 						  work);
147 	struct i2c_client *client = rx8025->client;
148 	struct mutex *lock = &rx8025->rtc->ops_lock;
149 	u8 status;
150 
151 	mutex_lock(lock);
152 
153 	if (rx8025_read_reg(client, RX8025_REG_CTRL2, &status))
154 		goto out;
155 
156 	if (!(status & RX8025_BIT_CTRL2_XST))
157 		dev_warn(&client->dev, "Oscillation stop was detected,"
158 			 "you may have to readjust the clock\n");
159 
160 	if (status & RX8025_BIT_CTRL2_CTFG) {
161 		/* periodic */
162 		status &= ~RX8025_BIT_CTRL2_CTFG;
163 		local_irq_disable();
164 		rtc_update_irq(rx8025->rtc, 1, RTC_PF | RTC_IRQF);
165 		local_irq_enable();
166 	}
167 
168 	if (status & RX8025_BIT_CTRL2_DAFG) {
169 		/* alarm */
170 		status &= RX8025_BIT_CTRL2_DAFG;
171 		if (rx8025_write_reg(client, RX8025_REG_CTRL1,
172 				     rx8025->ctrl1 & ~RX8025_BIT_CTRL1_DALE))
173 			goto out;
174 		local_irq_disable();
175 		rtc_update_irq(rx8025->rtc, 1, RTC_AF | RTC_IRQF);
176 		local_irq_enable();
177 	}
178 
179 	/* acknowledge IRQ */
180 	rx8025_write_reg(client, RX8025_REG_CTRL2,
181 			 status | RX8025_BIT_CTRL2_XST);
182 
183 out:
184 	if (!rx8025->exiting)
185 		enable_irq(client->irq);
186 
187 	mutex_unlock(lock);
188 }
189 
190 static int rx8025_get_time(struct device *dev, struct rtc_time *dt)
191 {
192 	struct rx8025_data *rx8025 = dev_get_drvdata(dev);
193 	u8 date[7];
194 	int err;
195 
196 	err = rx8025_read_regs(rx8025->client, RX8025_REG_SEC, 7, date);
197 	if (err)
198 		return err;
199 
200 	dev_dbg(dev, "%s: read 0x%02x 0x%02x "
201 		"0x%02x 0x%02x 0x%02x 0x%02x 0x%02x\n", __func__,
202 		date[0], date[1], date[2], date[3], date[4],
203 		date[5], date[6]);
204 
205 	dt->tm_sec = bcd2bin(date[RX8025_REG_SEC] & 0x7f);
206 	dt->tm_min = bcd2bin(date[RX8025_REG_MIN] & 0x7f);
207 	if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
208 		dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x3f);
209 	else
210 		dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x1f) % 12
211 			+ (date[RX8025_REG_HOUR] & 0x20 ? 12 : 0);
212 
213 	dt->tm_mday = bcd2bin(date[RX8025_REG_MDAY] & 0x3f);
214 	dt->tm_mon = bcd2bin(date[RX8025_REG_MONTH] & 0x1f) - 1;
215 	dt->tm_year = bcd2bin(date[RX8025_REG_YEAR]);
216 
217 	if (dt->tm_year < 70)
218 		dt->tm_year += 100;
219 
220 	dev_dbg(dev, "%s: date %ds %dm %dh %dmd %dm %dy\n", __func__,
221 		dt->tm_sec, dt->tm_min, dt->tm_hour,
222 		dt->tm_mday, dt->tm_mon, dt->tm_year);
223 
224 	return rtc_valid_tm(dt);
225 }
226 
227 static int rx8025_set_time(struct device *dev, struct rtc_time *dt)
228 {
229 	struct rx8025_data *rx8025 = dev_get_drvdata(dev);
230 	u8 date[7];
231 
232 	/*
233 	 * BUG: The HW assumes every year that is a multiple of 4 to be a leap
234 	 * year.  Next time this is wrong is 2100, which will not be a leap
235 	 * year.
236 	 */
237 
238 	/*
239 	 * Here the read-only bits are written as "0".  I'm not sure if that
240 	 * is sound.
241 	 */
242 	date[RX8025_REG_SEC] = bin2bcd(dt->tm_sec);
243 	date[RX8025_REG_MIN] = bin2bcd(dt->tm_min);
244 	if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
245 		date[RX8025_REG_HOUR] = bin2bcd(dt->tm_hour);
246 	else
247 		date[RX8025_REG_HOUR] = (dt->tm_hour >= 12 ? 0x20 : 0)
248 			| bin2bcd((dt->tm_hour + 11) % 12 + 1);
249 
250 	date[RX8025_REG_WDAY] = bin2bcd(dt->tm_wday);
251 	date[RX8025_REG_MDAY] = bin2bcd(dt->tm_mday);
252 	date[RX8025_REG_MONTH] = bin2bcd(dt->tm_mon + 1);
253 	date[RX8025_REG_YEAR] = bin2bcd(dt->tm_year % 100);
254 
255 	dev_dbg(dev,
256 		"%s: write 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x\n",
257 		__func__,
258 		date[0], date[1], date[2], date[3], date[4], date[5], date[6]);
259 
260 	return rx8025_write_regs(rx8025->client, RX8025_REG_SEC, 7, date);
261 }
262 
263 static int rx8025_init_client(struct i2c_client *client, int *need_reset)
264 {
265 	struct rx8025_data *rx8025 = i2c_get_clientdata(client);
266 	u8 ctrl[2], ctrl2;
267 	int need_clear = 0;
268 	int err;
269 
270 	err = rx8025_read_regs(rx8025->client, RX8025_REG_CTRL1, 2, ctrl);
271 	if (err)
272 		goto out;
273 
274 	/* Keep test bit zero ! */
275 	rx8025->ctrl1 = ctrl[0] & ~RX8025_BIT_CTRL1_TEST;
276 
277 	if (ctrl[1] & RX8025_BIT_CTRL2_PON) {
278 		dev_warn(&client->dev, "power-on reset was detected, "
279 			 "you may have to readjust the clock\n");
280 		*need_reset = 1;
281 	}
282 
283 	if (ctrl[1] & RX8025_BIT_CTRL2_VDET) {
284 		dev_warn(&client->dev, "a power voltage drop was detected, "
285 			 "you may have to readjust the clock\n");
286 		*need_reset = 1;
287 	}
288 
289 	if (!(ctrl[1] & RX8025_BIT_CTRL2_XST)) {
290 		dev_warn(&client->dev, "Oscillation stop was detected,"
291 			 "you may have to readjust the clock\n");
292 		*need_reset = 1;
293 	}
294 
295 	if (ctrl[1] & (RX8025_BIT_CTRL2_DAFG | RX8025_BIT_CTRL2_WAFG)) {
296 		dev_warn(&client->dev, "Alarm was detected\n");
297 		need_clear = 1;
298 	}
299 
300 	if (!(ctrl[1] & RX8025_BIT_CTRL2_CTFG))
301 		need_clear = 1;
302 
303 	if (*need_reset || need_clear) {
304 		ctrl2 = ctrl[0];
305 		ctrl2 &= ~(RX8025_BIT_CTRL2_PON | RX8025_BIT_CTRL2_VDET |
306 			   RX8025_BIT_CTRL2_CTFG | RX8025_BIT_CTRL2_WAFG |
307 			   RX8025_BIT_CTRL2_DAFG);
308 		ctrl2 |= RX8025_BIT_CTRL2_XST;
309 
310 		err = rx8025_write_reg(client, RX8025_REG_CTRL2, ctrl2);
311 	}
312 out:
313 	return err;
314 }
315 
316 /* Alarm support */
317 static int rx8025_read_alarm(struct device *dev, struct rtc_wkalrm *t)
318 {
319 	struct rx8025_data *rx8025 = dev_get_drvdata(dev);
320 	struct i2c_client *client = rx8025->client;
321 	u8 ctrl2, ald[2];
322 	int err;
323 
324 	if (client->irq <= 0)
325 		return -EINVAL;
326 
327 	err = rx8025_read_regs(client, RX8025_REG_ALDMIN, 2, ald);
328 	if (err)
329 		return err;
330 
331 	err = rx8025_read_reg(client, RX8025_REG_CTRL2, &ctrl2);
332 	if (err)
333 		return err;
334 
335 	dev_dbg(dev, "%s: read alarm 0x%02x 0x%02x ctrl2 %02x\n",
336 		__func__, ald[0], ald[1], ctrl2);
337 
338 	/* Hardware alarms precision is 1 minute! */
339 	t->time.tm_sec = 0;
340 	t->time.tm_min = bcd2bin(ald[0] & 0x7f);
341 	if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
342 		t->time.tm_hour = bcd2bin(ald[1] & 0x3f);
343 	else
344 		t->time.tm_hour = bcd2bin(ald[1] & 0x1f) % 12
345 			+ (ald[1] & 0x20 ? 12 : 0);
346 
347 	t->time.tm_wday = -1;
348 	t->time.tm_mday = -1;
349 	t->time.tm_mon = -1;
350 	t->time.tm_year = -1;
351 
352 	dev_dbg(dev, "%s: date: %ds %dm %dh %dmd %dm %dy\n",
353 		__func__,
354 		t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
355 		t->time.tm_mday, t->time.tm_mon, t->time.tm_year);
356 	t->enabled = !!(rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE);
357 	t->pending = (ctrl2 & RX8025_BIT_CTRL2_DAFG) && t->enabled;
358 
359 	return err;
360 }
361 
362 static int rx8025_set_alarm(struct device *dev, struct rtc_wkalrm *t)
363 {
364 	struct i2c_client *client = to_i2c_client(dev);
365 	struct rx8025_data *rx8025 = dev_get_drvdata(dev);
366 	u8 ald[2];
367 	int err;
368 
369 	if (client->irq <= 0)
370 		return -EINVAL;
371 
372 	/* Hardware alarm precision is 1 minute! */
373 	ald[0] = bin2bcd(t->time.tm_min);
374 	if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
375 		ald[1] = bin2bcd(t->time.tm_hour);
376 	else
377 		ald[1] = (t->time.tm_hour >= 12 ? 0x20 : 0)
378 			| bin2bcd((t->time.tm_hour + 11) % 12 + 1);
379 
380 	dev_dbg(dev, "%s: write 0x%02x 0x%02x\n", __func__, ald[0], ald[1]);
381 
382 	if (rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE) {
383 		rx8025->ctrl1 &= ~RX8025_BIT_CTRL1_DALE;
384 		err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
385 				       rx8025->ctrl1);
386 		if (err)
387 			return err;
388 	}
389 	err = rx8025_write_regs(rx8025->client, RX8025_REG_ALDMIN, 2, ald);
390 	if (err)
391 		return err;
392 
393 	if (t->enabled) {
394 		rx8025->ctrl1 |= RX8025_BIT_CTRL1_DALE;
395 		err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
396 				       rx8025->ctrl1);
397 		if (err)
398 			return err;
399 	}
400 
401 	return 0;
402 }
403 
404 static int rx8025_alarm_irq_enable(struct device *dev, unsigned int enabled)
405 {
406 	struct rx8025_data *rx8025 = dev_get_drvdata(dev);
407 	u8 ctrl1;
408 	int err;
409 
410 	ctrl1 = rx8025->ctrl1;
411 	if (enabled)
412 		ctrl1 |= RX8025_BIT_CTRL1_DALE;
413 	else
414 		ctrl1 &= ~RX8025_BIT_CTRL1_DALE;
415 
416 	if (ctrl1 != rx8025->ctrl1) {
417 		rx8025->ctrl1 = ctrl1;
418 		err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
419 				       rx8025->ctrl1);
420 		if (err)
421 			return err;
422 	}
423 	return 0;
424 }
425 
426 static int rx8025_irq_set_state(struct device *dev, int enabled)
427 {
428 	struct i2c_client *client = to_i2c_client(dev);
429 	struct rx8025_data *rx8025 = i2c_get_clientdata(client);
430 	int ctrl1;
431 	int err;
432 
433 	if (client->irq <= 0)
434 		return -ENXIO;
435 
436 	ctrl1 = rx8025->ctrl1 & ~RX8025_BIT_CTRL1_CT;
437 	if (enabled)
438 		ctrl1 |= RX8025_BIT_CTRL1_CT_1HZ;
439 	if (ctrl1 != rx8025->ctrl1) {
440 		rx8025->ctrl1 = ctrl1;
441 		err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
442 				       rx8025->ctrl1);
443 		if (err)
444 			return err;
445 	}
446 
447 	return 0;
448 }
449 
450 static struct rtc_class_ops rx8025_rtc_ops = {
451 	.read_time = rx8025_get_time,
452 	.set_time = rx8025_set_time,
453 	.read_alarm = rx8025_read_alarm,
454 	.set_alarm = rx8025_set_alarm,
455 	.alarm_irq_enable = rx8025_alarm_irq_enable,
456 	.irq_set_state  = rx8025_irq_set_state,
457 };
458 
459 /*
460  * Clock precision adjustment support
461  *
462  * According to the RX8025 SA/NB application manual the frequency and
463  * temperature charateristics can be approximated using the following
464  * equation:
465  *
466  *   df = a * (ut - t)**2
467  *
468  *   df: Frequency deviation in any temperature
469  *   a : Coefficient = (-35 +-5) * 10**-9
470  *   ut: Ultimate temperature in degree = +25 +-5 degree
471  *   t : Any temperature in degree
472  *
473  * Note that the clock adjustment in ppb must be entered (which is
474  * the negative value of the deviation).
475  */
476 static int rx8025_get_clock_adjust(struct device *dev, int *adj)
477 {
478 	struct i2c_client *client = to_i2c_client(dev);
479 	u8 digoff;
480 	int err;
481 
482 	err = rx8025_read_reg(client, RX8025_REG_DIGOFF, &digoff);
483 	if (err)
484 		return err;
485 
486 	*adj = digoff >= 64 ? digoff - 128 : digoff;
487 	if (*adj > 0)
488 		(*adj)--;
489 	*adj *= -RX8025_ADJ_RESOLUTION;
490 
491 	return 0;
492 }
493 
494 static int rx8025_set_clock_adjust(struct device *dev, int adj)
495 {
496 	struct i2c_client *client = to_i2c_client(dev);
497 	u8 digoff;
498 	int err;
499 
500 	adj /= -RX8025_ADJ_RESOLUTION;
501 	if (adj > RX8025_ADJ_DATA_MAX)
502 		adj = RX8025_ADJ_DATA_MAX;
503 	else if (adj < RX8025_ADJ_DATA_MIN)
504 		adj = RX8025_ADJ_DATA_MIN;
505 	else if (adj > 0)
506 		adj++;
507 	else if (adj < 0)
508 		adj += 128;
509 	digoff = adj;
510 
511 	err = rx8025_write_reg(client, RX8025_REG_DIGOFF, digoff);
512 	if (err)
513 		return err;
514 
515 	dev_dbg(dev, "%s: write 0x%02x\n", __func__, digoff);
516 
517 	return 0;
518 }
519 
520 static ssize_t rx8025_sysfs_show_clock_adjust(struct device *dev,
521 					      struct device_attribute *attr,
522 					      char *buf)
523 {
524 	int err, adj;
525 
526 	err = rx8025_get_clock_adjust(dev, &adj);
527 	if (err)
528 		return err;
529 
530 	return sprintf(buf, "%d\n", adj);
531 }
532 
533 static ssize_t rx8025_sysfs_store_clock_adjust(struct device *dev,
534 					       struct device_attribute *attr,
535 					       const char *buf, size_t count)
536 {
537 	int adj, err;
538 
539 	if (sscanf(buf, "%i", &adj) != 1)
540 		return -EINVAL;
541 
542 	err = rx8025_set_clock_adjust(dev, adj);
543 
544 	return err ? err : count;
545 }
546 
547 static DEVICE_ATTR(clock_adjust_ppb, S_IRUGO | S_IWUSR,
548 		   rx8025_sysfs_show_clock_adjust,
549 		   rx8025_sysfs_store_clock_adjust);
550 
551 static int rx8025_sysfs_register(struct device *dev)
552 {
553 	return device_create_file(dev, &dev_attr_clock_adjust_ppb);
554 }
555 
556 static void rx8025_sysfs_unregister(struct device *dev)
557 {
558 	device_remove_file(dev, &dev_attr_clock_adjust_ppb);
559 }
560 
561 static int __devinit rx8025_probe(struct i2c_client *client,
562 				  const struct i2c_device_id *id)
563 {
564 	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
565 	struct rx8025_data *rx8025;
566 	int err, need_reset = 0;
567 
568 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
569 				     | I2C_FUNC_SMBUS_I2C_BLOCK)) {
570 		dev_err(&adapter->dev,
571 			"doesn't support required functionality\n");
572 		err = -EIO;
573 		goto errout;
574 	}
575 
576 	rx8025 = kzalloc(sizeof(*rx8025), GFP_KERNEL);
577 	if (!rx8025) {
578 		dev_err(&adapter->dev, "failed to alloc memory\n");
579 		err = -ENOMEM;
580 		goto errout;
581 	}
582 
583 	rx8025->client = client;
584 	i2c_set_clientdata(client, rx8025);
585 	INIT_WORK(&rx8025->work, rx8025_work);
586 
587 	err = rx8025_init_client(client, &need_reset);
588 	if (err)
589 		goto errout_free;
590 
591 	if (need_reset) {
592 		struct rtc_time tm;
593 		dev_info(&client->dev,
594 			 "bad conditions detected, resetting date\n");
595 		rtc_time_to_tm(0, &tm);	/* 1970/1/1 */
596 		rx8025_set_time(&client->dev, &tm);
597 	}
598 
599 	rx8025->rtc = rtc_device_register(client->name, &client->dev,
600 					  &rx8025_rtc_ops, THIS_MODULE);
601 	if (IS_ERR(rx8025->rtc)) {
602 		err = PTR_ERR(rx8025->rtc);
603 		dev_err(&client->dev, "unable to register the class device\n");
604 		goto errout_free;
605 	}
606 
607 	if (client->irq > 0) {
608 		dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
609 		err = request_irq(client->irq, rx8025_irq,
610 				  0, "rx8025", client);
611 		if (err) {
612 			dev_err(&client->dev, "unable to request IRQ\n");
613 			goto errout_reg;
614 		}
615 	}
616 
617 	rx8025->rtc->irq_freq = 1;
618 	rx8025->rtc->max_user_freq = 1;
619 
620 	err = rx8025_sysfs_register(&client->dev);
621 	if (err)
622 		goto errout_irq;
623 
624 	return 0;
625 
626 errout_irq:
627 	if (client->irq > 0)
628 		free_irq(client->irq, client);
629 
630 errout_reg:
631 	rtc_device_unregister(rx8025->rtc);
632 
633 errout_free:
634 	i2c_set_clientdata(client, NULL);
635 	kfree(rx8025);
636 
637 errout:
638 	dev_err(&adapter->dev, "probing for rx8025 failed\n");
639 	return err;
640 }
641 
642 static int __devexit rx8025_remove(struct i2c_client *client)
643 {
644 	struct rx8025_data *rx8025 = i2c_get_clientdata(client);
645 	struct mutex *lock = &rx8025->rtc->ops_lock;
646 
647 	if (client->irq > 0) {
648 		mutex_lock(lock);
649 		rx8025->exiting = 1;
650 		mutex_unlock(lock);
651 
652 		free_irq(client->irq, client);
653 		flush_scheduled_work();
654 	}
655 
656 	rx8025_sysfs_unregister(&client->dev);
657 	rtc_device_unregister(rx8025->rtc);
658 	i2c_set_clientdata(client, NULL);
659 	kfree(rx8025);
660 	return 0;
661 }
662 
663 static struct i2c_driver rx8025_driver = {
664 	.driver = {
665 		.name = "rtc-rx8025",
666 		.owner = THIS_MODULE,
667 	},
668 	.probe		= rx8025_probe,
669 	.remove		= __devexit_p(rx8025_remove),
670 	.id_table	= rx8025_id,
671 };
672 
673 static int __init rx8025_init(void)
674 {
675 	return i2c_add_driver(&rx8025_driver);
676 }
677 
678 static void __exit rx8025_exit(void)
679 {
680 	i2c_del_driver(&rx8025_driver);
681 }
682 
683 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
684 MODULE_DESCRIPTION("RX-8025 SA/NB RTC driver");
685 MODULE_LICENSE("GPL");
686 
687 module_init(rx8025_init);
688 module_exit(rx8025_exit);
689