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1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Driver for Epson's RTC module RX-8025 SA/NB
4  *
5  * Copyright (C) 2009 Wolfgang Grandegger <wg@grandegger.com>
6  *
7  * Copyright (C) 2005 by Digi International Inc.
8  * All rights reserved.
9  *
10  * Modified by fengjh at rising.com.cn
11  * <lm-sensors@lm-sensors.org>
12  * 2006.11
13  *
14  * Code cleanup by Sergei Poselenov, <sposelenov@emcraft.com>
15  * Converted to new style by Wolfgang Grandegger <wg@grandegger.com>
16  * Alarm and periodic interrupt added by Dmitry Rakhchev <rda@emcraft.com>
17  */
18 #include <linux/bcd.h>
19 #include <linux/bitops.h>
20 #include <linux/i2c.h>
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/rtc.h>
24 
25 /* Register definitions */
26 #define RX8025_REG_SEC		0x00
27 #define RX8025_REG_MIN		0x01
28 #define RX8025_REG_HOUR		0x02
29 #define RX8025_REG_WDAY		0x03
30 #define RX8025_REG_MDAY		0x04
31 #define RX8025_REG_MONTH	0x05
32 #define RX8025_REG_YEAR		0x06
33 #define RX8025_REG_DIGOFF	0x07
34 #define RX8025_REG_ALWMIN	0x08
35 #define RX8025_REG_ALWHOUR	0x09
36 #define RX8025_REG_ALWWDAY	0x0a
37 #define RX8025_REG_ALDMIN	0x0b
38 #define RX8025_REG_ALDHOUR	0x0c
39 /* 0x0d is reserved */
40 #define RX8025_REG_CTRL1	0x0e
41 #define RX8025_REG_CTRL2	0x0f
42 
43 #define RX8025_BIT_CTRL1_CT	(7 << 0)
44 /* 1 Hz periodic level irq */
45 #define RX8025_BIT_CTRL1_CT_1HZ	4
46 #define RX8025_BIT_CTRL1_TEST	BIT(3)
47 #define RX8025_BIT_CTRL1_1224	BIT(5)
48 #define RX8025_BIT_CTRL1_DALE	BIT(6)
49 #define RX8025_BIT_CTRL1_WALE	BIT(7)
50 
51 #define RX8025_BIT_CTRL2_DAFG	BIT(0)
52 #define RX8025_BIT_CTRL2_WAFG	BIT(1)
53 #define RX8025_BIT_CTRL2_CTFG	BIT(2)
54 #define RX8025_BIT_CTRL2_PON	BIT(4)
55 #define RX8025_BIT_CTRL2_XST	BIT(5)
56 #define RX8025_BIT_CTRL2_VDET	BIT(6)
57 
58 #define RX8035_BIT_HOUR_1224	BIT(7)
59 
60 /* Clock precision adjustment */
61 #define RX8025_ADJ_RESOLUTION	3050 /* in ppb */
62 #define RX8025_ADJ_DATA_MAX	62
63 #define RX8025_ADJ_DATA_MIN	-62
64 
65 enum rx_model {
66 	model_rx_unknown,
67 	model_rx_8025,
68 	model_rx_8035,
69 	model_last
70 };
71 
72 static const struct i2c_device_id rx8025_id[] = {
73 	{ "rx8025", model_rx_8025 },
74 	{ "rx8035", model_rx_8035 },
75 	{ }
76 };
77 MODULE_DEVICE_TABLE(i2c, rx8025_id);
78 
79 struct rx8025_data {
80 	struct rtc_device *rtc;
81 	enum rx_model model;
82 	u8 ctrl1;
83 	int is_24;
84 };
85 
rx8025_read_reg(const struct i2c_client * client,u8 number)86 static s32 rx8025_read_reg(const struct i2c_client *client, u8 number)
87 {
88 	return i2c_smbus_read_byte_data(client, number << 4);
89 }
90 
rx8025_read_regs(const struct i2c_client * client,u8 number,u8 length,u8 * values)91 static int rx8025_read_regs(const struct i2c_client *client,
92 			    u8 number, u8 length, u8 *values)
93 {
94 	int ret = i2c_smbus_read_i2c_block_data(client, number << 4, length,
95 						values);
96 	if (ret != length)
97 		return ret < 0 ? ret : -EIO;
98 
99 	return 0;
100 }
101 
rx8025_write_reg(const struct i2c_client * client,u8 number,u8 value)102 static s32 rx8025_write_reg(const struct i2c_client *client, u8 number,
103 			    u8 value)
104 {
105 	return i2c_smbus_write_byte_data(client, number << 4, value);
106 }
107 
rx8025_write_regs(const struct i2c_client * client,u8 number,u8 length,const u8 * values)108 static s32 rx8025_write_regs(const struct i2c_client *client,
109 			     u8 number, u8 length, const u8 *values)
110 {
111 	return i2c_smbus_write_i2c_block_data(client, number << 4,
112 					      length, values);
113 }
114 
rx8025_is_osc_stopped(enum rx_model model,int ctrl2)115 static int rx8025_is_osc_stopped(enum rx_model model, int ctrl2)
116 {
117 	int xstp = ctrl2 & RX8025_BIT_CTRL2_XST;
118 	/* XSTP bit has different polarity on RX-8025 vs RX-8035.
119 	 * RX-8025: 0 == oscillator stopped
120 	 * RX-8035: 1 == oscillator stopped
121 	 */
122 
123 	if (model == model_rx_8025)
124 		xstp = !xstp;
125 
126 	return xstp;
127 }
128 
rx8025_check_validity(struct device * dev)129 static int rx8025_check_validity(struct device *dev)
130 {
131 	struct i2c_client *client = to_i2c_client(dev);
132 	struct rx8025_data *drvdata = dev_get_drvdata(dev);
133 	int ctrl2;
134 	int xstp;
135 
136 	ctrl2 = rx8025_read_reg(client, RX8025_REG_CTRL2);
137 	if (ctrl2 < 0)
138 		return ctrl2;
139 
140 	if (ctrl2 & RX8025_BIT_CTRL2_VDET)
141 		dev_warn(dev, "power voltage drop detected\n");
142 
143 	if (ctrl2 & RX8025_BIT_CTRL2_PON) {
144 		dev_warn(dev, "power-on reset detected, date is invalid\n");
145 		return -EINVAL;
146 	}
147 
148 	xstp = rx8025_is_osc_stopped(drvdata->model, ctrl2);
149 	if (xstp) {
150 		dev_warn(dev, "crystal stopped, date is invalid\n");
151 		return -EINVAL;
152 	}
153 
154 	return 0;
155 }
156 
rx8025_reset_validity(struct i2c_client * client)157 static int rx8025_reset_validity(struct i2c_client *client)
158 {
159 	struct rx8025_data *drvdata = i2c_get_clientdata(client);
160 	int ctrl2 = rx8025_read_reg(client, RX8025_REG_CTRL2);
161 
162 	if (ctrl2 < 0)
163 		return ctrl2;
164 
165 	ctrl2 &= ~(RX8025_BIT_CTRL2_PON | RX8025_BIT_CTRL2_VDET);
166 
167 	if (drvdata->model == model_rx_8025)
168 		ctrl2 |= RX8025_BIT_CTRL2_XST;
169 	else
170 		ctrl2 &= ~(RX8025_BIT_CTRL2_XST);
171 
172 	return rx8025_write_reg(client, RX8025_REG_CTRL2,
173 				ctrl2);
174 }
175 
rx8025_handle_irq(int irq,void * dev_id)176 static irqreturn_t rx8025_handle_irq(int irq, void *dev_id)
177 {
178 	struct i2c_client *client = dev_id;
179 	struct rx8025_data *rx8025 = i2c_get_clientdata(client);
180 	int status, xstp;
181 
182 	rtc_lock(rx8025->rtc);
183 	status = rx8025_read_reg(client, RX8025_REG_CTRL2);
184 	if (status < 0)
185 		goto out;
186 
187 	xstp = rx8025_is_osc_stopped(rx8025->model, status);
188 	if (xstp)
189 		dev_warn(&client->dev, "Oscillation stop was detected,"
190 			 "you may have to readjust the clock\n");
191 
192 	if (status & RX8025_BIT_CTRL2_CTFG) {
193 		/* periodic */
194 		status &= ~RX8025_BIT_CTRL2_CTFG;
195 		rtc_update_irq(rx8025->rtc, 1, RTC_PF | RTC_IRQF);
196 	}
197 
198 	if (status & RX8025_BIT_CTRL2_DAFG) {
199 		/* alarm */
200 		status &= RX8025_BIT_CTRL2_DAFG;
201 		if (rx8025_write_reg(client, RX8025_REG_CTRL1,
202 				     rx8025->ctrl1 & ~RX8025_BIT_CTRL1_DALE))
203 			goto out;
204 		rtc_update_irq(rx8025->rtc, 1, RTC_AF | RTC_IRQF);
205 	}
206 
207 out:
208 	rtc_unlock(rx8025->rtc);
209 
210 	return IRQ_HANDLED;
211 }
212 
rx8025_get_time(struct device * dev,struct rtc_time * dt)213 static int rx8025_get_time(struct device *dev, struct rtc_time *dt)
214 {
215 	struct i2c_client *client = to_i2c_client(dev);
216 	struct rx8025_data *rx8025 = dev_get_drvdata(dev);
217 	u8 date[7];
218 	int err;
219 
220 	err = rx8025_check_validity(dev);
221 	if (err)
222 		return err;
223 
224 	err = rx8025_read_regs(client, RX8025_REG_SEC, 7, date);
225 	if (err)
226 		return err;
227 
228 	dev_dbg(dev, "%s: read %7ph\n", __func__, date);
229 
230 	dt->tm_sec = bcd2bin(date[RX8025_REG_SEC] & 0x7f);
231 	dt->tm_min = bcd2bin(date[RX8025_REG_MIN] & 0x7f);
232 	if (rx8025->is_24)
233 		dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x3f);
234 	else
235 		dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x1f) % 12
236 			+ (date[RX8025_REG_HOUR] & 0x20 ? 12 : 0);
237 
238 	dt->tm_mday = bcd2bin(date[RX8025_REG_MDAY] & 0x3f);
239 	dt->tm_mon = bcd2bin(date[RX8025_REG_MONTH] & 0x1f) - 1;
240 	dt->tm_year = bcd2bin(date[RX8025_REG_YEAR]) + 100;
241 
242 	dev_dbg(dev, "%s: date %ptRr\n", __func__, dt);
243 
244 	return 0;
245 }
246 
rx8025_set_time(struct device * dev,struct rtc_time * dt)247 static int rx8025_set_time(struct device *dev, struct rtc_time *dt)
248 {
249 	struct i2c_client *client = to_i2c_client(dev);
250 	struct rx8025_data *rx8025 = dev_get_drvdata(dev);
251 	u8 date[7];
252 	int ret;
253 
254 	if ((dt->tm_year < 100) || (dt->tm_year > 199))
255 		return -EINVAL;
256 
257 	/*
258 	 * Here the read-only bits are written as "0".  I'm not sure if that
259 	 * is sound.
260 	 */
261 	date[RX8025_REG_SEC] = bin2bcd(dt->tm_sec);
262 	date[RX8025_REG_MIN] = bin2bcd(dt->tm_min);
263 	if (rx8025->is_24)
264 		date[RX8025_REG_HOUR] = bin2bcd(dt->tm_hour);
265 	else
266 		date[RX8025_REG_HOUR] = (dt->tm_hour >= 12 ? 0x20 : 0)
267 			| bin2bcd((dt->tm_hour + 11) % 12 + 1);
268 
269 	date[RX8025_REG_WDAY] = bin2bcd(dt->tm_wday);
270 	date[RX8025_REG_MDAY] = bin2bcd(dt->tm_mday);
271 	date[RX8025_REG_MONTH] = bin2bcd(dt->tm_mon + 1);
272 	date[RX8025_REG_YEAR] = bin2bcd(dt->tm_year - 100);
273 
274 	dev_dbg(dev, "%s: write %7ph\n", __func__, date);
275 
276 	ret = rx8025_write_regs(client, RX8025_REG_SEC, 7, date);
277 	if (ret < 0)
278 		return ret;
279 
280 	return rx8025_reset_validity(client);
281 }
282 
rx8025_init_client(struct i2c_client * client)283 static int rx8025_init_client(struct i2c_client *client)
284 {
285 	struct rx8025_data *rx8025 = i2c_get_clientdata(client);
286 	u8 ctrl[2], ctrl2;
287 	int need_clear = 0;
288 	int hour_reg;
289 	int err;
290 
291 	err = rx8025_read_regs(client, RX8025_REG_CTRL1, 2, ctrl);
292 	if (err)
293 		goto out;
294 
295 	/* Keep test bit zero ! */
296 	rx8025->ctrl1 = ctrl[0] & ~RX8025_BIT_CTRL1_TEST;
297 
298 	if (ctrl[1] & (RX8025_BIT_CTRL2_DAFG | RX8025_BIT_CTRL2_WAFG)) {
299 		dev_warn(&client->dev, "Alarm was detected\n");
300 		need_clear = 1;
301 	}
302 
303 	if (ctrl[1] & RX8025_BIT_CTRL2_CTFG)
304 		need_clear = 1;
305 
306 	if (need_clear) {
307 		ctrl2 = ctrl[1];
308 		ctrl2 &= ~(RX8025_BIT_CTRL2_CTFG | RX8025_BIT_CTRL2_WAFG |
309 			   RX8025_BIT_CTRL2_DAFG);
310 
311 		err = rx8025_write_reg(client, RX8025_REG_CTRL2, ctrl2);
312 	}
313 
314 	if (rx8025->model == model_rx_8035) {
315 		/* In RX-8035, 12/24 flag is in the hour register */
316 		hour_reg = rx8025_read_reg(client, RX8025_REG_HOUR);
317 		if (hour_reg < 0)
318 			return hour_reg;
319 		rx8025->is_24 = (hour_reg & RX8035_BIT_HOUR_1224);
320 	} else {
321 		rx8025->is_24 = (ctrl[1] & RX8025_BIT_CTRL1_1224);
322 	}
323 out:
324 	return err;
325 }
326 
327 /* Alarm support */
rx8025_read_alarm(struct device * dev,struct rtc_wkalrm * t)328 static int rx8025_read_alarm(struct device *dev, struct rtc_wkalrm *t)
329 {
330 	struct i2c_client *client = to_i2c_client(dev);
331 	struct rx8025_data *rx8025 = dev_get_drvdata(dev);
332 	u8 ald[2];
333 	int ctrl2, err;
334 
335 	if (client->irq <= 0)
336 		return -EINVAL;
337 
338 	err = rx8025_read_regs(client, RX8025_REG_ALDMIN, 2, ald);
339 	if (err)
340 		return err;
341 
342 	ctrl2 = rx8025_read_reg(client, RX8025_REG_CTRL2);
343 	if (ctrl2 < 0)
344 		return ctrl2;
345 
346 	dev_dbg(dev, "%s: read alarm 0x%02x 0x%02x ctrl2 %02x\n",
347 		__func__, ald[0], ald[1], ctrl2);
348 
349 	/* Hardware alarms precision is 1 minute! */
350 	t->time.tm_sec = 0;
351 	t->time.tm_min = bcd2bin(ald[0] & 0x7f);
352 	if (rx8025->is_24)
353 		t->time.tm_hour = bcd2bin(ald[1] & 0x3f);
354 	else
355 		t->time.tm_hour = bcd2bin(ald[1] & 0x1f) % 12
356 			+ (ald[1] & 0x20 ? 12 : 0);
357 
358 	dev_dbg(dev, "%s: date: %ptRr\n", __func__, &t->time);
359 	t->enabled = !!(rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE);
360 	t->pending = (ctrl2 & RX8025_BIT_CTRL2_DAFG) && t->enabled;
361 
362 	return err;
363 }
364 
rx8025_set_alarm(struct device * dev,struct rtc_wkalrm * t)365 static int rx8025_set_alarm(struct device *dev, struct rtc_wkalrm *t)
366 {
367 	struct i2c_client *client = to_i2c_client(dev);
368 	struct rx8025_data *rx8025 = dev_get_drvdata(dev);
369 	u8 ald[2];
370 	int err;
371 
372 	if (client->irq <= 0)
373 		return -EINVAL;
374 
375 	/*
376 	 * Hardware alarm precision is 1 minute!
377 	 * round up to nearest minute
378 	 */
379 	if (t->time.tm_sec) {
380 		time64_t alarm_time = rtc_tm_to_time64(&t->time);
381 
382 		alarm_time += 60 - t->time.tm_sec;
383 		rtc_time64_to_tm(alarm_time, &t->time);
384 	}
385 
386 	ald[0] = bin2bcd(t->time.tm_min);
387 	if (rx8025->is_24)
388 		ald[1] = bin2bcd(t->time.tm_hour);
389 	else
390 		ald[1] = (t->time.tm_hour >= 12 ? 0x20 : 0)
391 			| bin2bcd((t->time.tm_hour + 11) % 12 + 1);
392 
393 	dev_dbg(dev, "%s: write 0x%02x 0x%02x\n", __func__, ald[0], ald[1]);
394 
395 	if (rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE) {
396 		rx8025->ctrl1 &= ~RX8025_BIT_CTRL1_DALE;
397 		err = rx8025_write_reg(client, RX8025_REG_CTRL1,
398 				       rx8025->ctrl1);
399 		if (err)
400 			return err;
401 	}
402 	err = rx8025_write_regs(client, RX8025_REG_ALDMIN, 2, ald);
403 	if (err)
404 		return err;
405 
406 	if (t->enabled) {
407 		rx8025->ctrl1 |= RX8025_BIT_CTRL1_DALE;
408 		err = rx8025_write_reg(client, RX8025_REG_CTRL1,
409 				       rx8025->ctrl1);
410 		if (err)
411 			return err;
412 	}
413 
414 	return 0;
415 }
416 
rx8025_alarm_irq_enable(struct device * dev,unsigned int enabled)417 static int rx8025_alarm_irq_enable(struct device *dev, unsigned int enabled)
418 {
419 	struct i2c_client *client = to_i2c_client(dev);
420 	struct rx8025_data *rx8025 = dev_get_drvdata(dev);
421 	u8 ctrl1;
422 	int err;
423 
424 	ctrl1 = rx8025->ctrl1;
425 	if (enabled)
426 		ctrl1 |= RX8025_BIT_CTRL1_DALE;
427 	else
428 		ctrl1 &= ~RX8025_BIT_CTRL1_DALE;
429 
430 	if (ctrl1 != rx8025->ctrl1) {
431 		rx8025->ctrl1 = ctrl1;
432 		err = rx8025_write_reg(client, RX8025_REG_CTRL1,
433 				       rx8025->ctrl1);
434 		if (err)
435 			return err;
436 	}
437 	return 0;
438 }
439 
440 static const struct rtc_class_ops rx8025_rtc_ops = {
441 	.read_time = rx8025_get_time,
442 	.set_time = rx8025_set_time,
443 	.read_alarm = rx8025_read_alarm,
444 	.set_alarm = rx8025_set_alarm,
445 	.alarm_irq_enable = rx8025_alarm_irq_enable,
446 };
447 
448 /*
449  * Clock precision adjustment support
450  *
451  * According to the RX8025 SA/NB application manual the frequency and
452  * temperature characteristics can be approximated using the following
453  * equation:
454  *
455  *   df = a * (ut - t)**2
456  *
457  *   df: Frequency deviation in any temperature
458  *   a : Coefficient = (-35 +-5) * 10**-9
459  *   ut: Ultimate temperature in degree = +25 +-5 degree
460  *   t : Any temperature in degree
461  *
462  * Note that the clock adjustment in ppb must be entered (which is
463  * the negative value of the deviation).
464  */
rx8025_get_clock_adjust(struct device * dev,int * adj)465 static int rx8025_get_clock_adjust(struct device *dev, int *adj)
466 {
467 	struct i2c_client *client = to_i2c_client(dev);
468 	int digoff;
469 
470 	digoff = rx8025_read_reg(client, RX8025_REG_DIGOFF);
471 	if (digoff < 0)
472 		return digoff;
473 
474 	*adj = digoff >= 64 ? digoff - 128 : digoff;
475 	if (*adj > 0)
476 		(*adj)--;
477 	*adj *= -RX8025_ADJ_RESOLUTION;
478 
479 	return 0;
480 }
481 
rx8025_set_clock_adjust(struct device * dev,int adj)482 static int rx8025_set_clock_adjust(struct device *dev, int adj)
483 {
484 	struct i2c_client *client = to_i2c_client(dev);
485 	u8 digoff;
486 	int err;
487 
488 	adj /= -RX8025_ADJ_RESOLUTION;
489 	if (adj > RX8025_ADJ_DATA_MAX)
490 		adj = RX8025_ADJ_DATA_MAX;
491 	else if (adj < RX8025_ADJ_DATA_MIN)
492 		adj = RX8025_ADJ_DATA_MIN;
493 	else if (adj > 0)
494 		adj++;
495 	else if (adj < 0)
496 		adj += 128;
497 	digoff = adj;
498 
499 	err = rx8025_write_reg(client, RX8025_REG_DIGOFF, digoff);
500 	if (err)
501 		return err;
502 
503 	dev_dbg(dev, "%s: write 0x%02x\n", __func__, digoff);
504 
505 	return 0;
506 }
507 
rx8025_sysfs_show_clock_adjust(struct device * dev,struct device_attribute * attr,char * buf)508 static ssize_t rx8025_sysfs_show_clock_adjust(struct device *dev,
509 					      struct device_attribute *attr,
510 					      char *buf)
511 {
512 	int err, adj;
513 
514 	err = rx8025_get_clock_adjust(dev, &adj);
515 	if (err)
516 		return err;
517 
518 	return sprintf(buf, "%d\n", adj);
519 }
520 
rx8025_sysfs_store_clock_adjust(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)521 static ssize_t rx8025_sysfs_store_clock_adjust(struct device *dev,
522 					       struct device_attribute *attr,
523 					       const char *buf, size_t count)
524 {
525 	int adj, err;
526 
527 	if (sscanf(buf, "%i", &adj) != 1)
528 		return -EINVAL;
529 
530 	err = rx8025_set_clock_adjust(dev, adj);
531 
532 	return err ? err : count;
533 }
534 
535 static DEVICE_ATTR(clock_adjust_ppb, S_IRUGO | S_IWUSR,
536 		   rx8025_sysfs_show_clock_adjust,
537 		   rx8025_sysfs_store_clock_adjust);
538 
rx8025_sysfs_register(struct device * dev)539 static int rx8025_sysfs_register(struct device *dev)
540 {
541 	return device_create_file(dev, &dev_attr_clock_adjust_ppb);
542 }
543 
rx8025_sysfs_unregister(struct device * dev)544 static void rx8025_sysfs_unregister(struct device *dev)
545 {
546 	device_remove_file(dev, &dev_attr_clock_adjust_ppb);
547 }
548 
rx8025_probe(struct i2c_client * client,const struct i2c_device_id * id)549 static int rx8025_probe(struct i2c_client *client,
550 			const struct i2c_device_id *id)
551 {
552 	struct i2c_adapter *adapter = client->adapter;
553 	struct rx8025_data *rx8025;
554 	int err = 0;
555 
556 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
557 				     | I2C_FUNC_SMBUS_I2C_BLOCK)) {
558 		dev_err(&adapter->dev,
559 			"doesn't support required functionality\n");
560 		return -EIO;
561 	}
562 
563 	rx8025 = devm_kzalloc(&client->dev, sizeof(*rx8025), GFP_KERNEL);
564 	if (!rx8025)
565 		return -ENOMEM;
566 
567 	i2c_set_clientdata(client, rx8025);
568 
569 	if (id)
570 		rx8025->model = id->driver_data;
571 
572 	err = rx8025_init_client(client);
573 	if (err)
574 		return err;
575 
576 	rx8025->rtc = devm_rtc_device_register(&client->dev, client->name,
577 					  &rx8025_rtc_ops, THIS_MODULE);
578 	if (IS_ERR(rx8025->rtc)) {
579 		dev_err(&client->dev, "unable to register the class device\n");
580 		return PTR_ERR(rx8025->rtc);
581 	}
582 
583 	if (client->irq > 0) {
584 		dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
585 		err = devm_request_threaded_irq(&client->dev, client->irq, NULL,
586 						rx8025_handle_irq,
587 						IRQF_ONESHOT,
588 						"rx8025", client);
589 		if (err) {
590 			dev_err(&client->dev, "unable to request IRQ, alarms disabled\n");
591 			client->irq = 0;
592 		}
593 	}
594 
595 	rx8025->rtc->max_user_freq = 1;
596 
597 	/* the rx8025 alarm only supports a minute accuracy */
598 	rx8025->rtc->uie_unsupported = 1;
599 
600 	err = rx8025_sysfs_register(&client->dev);
601 	return err;
602 }
603 
rx8025_remove(struct i2c_client * client)604 static int rx8025_remove(struct i2c_client *client)
605 {
606 	rx8025_sysfs_unregister(&client->dev);
607 	return 0;
608 }
609 
610 static struct i2c_driver rx8025_driver = {
611 	.driver = {
612 		.name = "rtc-rx8025",
613 	},
614 	.probe		= rx8025_probe,
615 	.remove		= rx8025_remove,
616 	.id_table	= rx8025_id,
617 };
618 
619 module_i2c_driver(rx8025_driver);
620 
621 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
622 MODULE_DESCRIPTION("RX-8025 SA/NB RTC driver");
623 MODULE_LICENSE("GPL");
624