xref: /linux/drivers/rtc/rtc-ds1343.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /* rtc-ds1343.c
2  *
3  * Driver for Dallas Semiconductor DS1343 Low Current, SPI Compatible
4  * Real Time Clock
5  *
6  * Author : Raghavendra Chandra Ganiga <ravi23ganiga@gmail.com>
7  *	    Ankur Srivastava <sankurece@gmail.com> : DS1343 Nvram Support
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  *
13  */
14 
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/interrupt.h>
18 #include <linux/device.h>
19 #include <linux/spi/spi.h>
20 #include <linux/regmap.h>
21 #include <linux/rtc.h>
22 #include <linux/bcd.h>
23 #include <linux/pm.h>
24 #include <linux/slab.h>
25 
26 #define DS1343_DRV_VERSION	"01.00"
27 #define DALLAS_MAXIM_DS1343	0
28 #define DALLAS_MAXIM_DS1344	1
29 
30 /* RTC DS1343 Registers */
31 #define DS1343_SECONDS_REG	0x00
32 #define DS1343_MINUTES_REG	0x01
33 #define DS1343_HOURS_REG	0x02
34 #define DS1343_DAY_REG		0x03
35 #define DS1343_DATE_REG		0x04
36 #define DS1343_MONTH_REG	0x05
37 #define DS1343_YEAR_REG		0x06
38 #define DS1343_ALM0_SEC_REG	0x07
39 #define DS1343_ALM0_MIN_REG	0x08
40 #define DS1343_ALM0_HOUR_REG	0x09
41 #define DS1343_ALM0_DAY_REG	0x0A
42 #define DS1343_ALM1_SEC_REG	0x0B
43 #define DS1343_ALM1_MIN_REG	0x0C
44 #define DS1343_ALM1_HOUR_REG	0x0D
45 #define DS1343_ALM1_DAY_REG	0x0E
46 #define DS1343_CONTROL_REG	0x0F
47 #define DS1343_STATUS_REG	0x10
48 #define DS1343_TRICKLE_REG	0x11
49 #define DS1343_NVRAM		0x20
50 
51 #define DS1343_NVRAM_LEN	96
52 
53 /* DS1343 Control Registers bits */
54 #define DS1343_EOSC		0x80
55 #define DS1343_DOSF		0x20
56 #define DS1343_EGFIL		0x10
57 #define DS1343_SQW		0x08
58 #define DS1343_INTCN		0x04
59 #define DS1343_A1IE		0x02
60 #define DS1343_A0IE		0x01
61 
62 /* DS1343 Status Registers bits */
63 #define DS1343_OSF		0x80
64 #define DS1343_IRQF1		0x02
65 #define DS1343_IRQF0		0x01
66 
67 /* DS1343 Trickle Charger Registers bits */
68 #define DS1343_TRICKLE_MAGIC	0xa0
69 #define DS1343_TRICKLE_DS1	0x08
70 #define DS1343_TRICKLE_1K	0x01
71 #define DS1343_TRICKLE_2K	0x02
72 #define DS1343_TRICKLE_4K	0x03
73 
74 static const struct spi_device_id ds1343_id[] = {
75 	{ "ds1343", DALLAS_MAXIM_DS1343 },
76 	{ "ds1344", DALLAS_MAXIM_DS1344 },
77 	{ }
78 };
79 MODULE_DEVICE_TABLE(spi, ds1343_id);
80 
81 struct ds1343_priv {
82 	struct spi_device *spi;
83 	struct rtc_device *rtc;
84 	struct regmap *map;
85 	struct mutex mutex;
86 	unsigned int irqen;
87 	int irq;
88 	int alarm_sec;
89 	int alarm_min;
90 	int alarm_hour;
91 	int alarm_mday;
92 };
93 
94 static int ds1343_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
95 {
96 	switch (cmd) {
97 #ifdef RTC_SET_CHARGE
98 	case RTC_SET_CHARGE:
99 	{
100 		int val;
101 
102 		if (copy_from_user(&val, (int __user *)arg, sizeof(int)))
103 			return -EFAULT;
104 
105 		return regmap_write(priv->map, DS1343_TRICKLE_REG, val);
106 	}
107 	break;
108 #endif
109 	}
110 
111 	return -ENOIOCTLCMD;
112 }
113 
114 static ssize_t ds1343_show_glitchfilter(struct device *dev,
115 				struct device_attribute *attr, char *buf)
116 {
117 	struct ds1343_priv *priv = dev_get_drvdata(dev);
118 	int glitch_filt_status, data;
119 
120 	regmap_read(priv->map, DS1343_CONTROL_REG, &data);
121 
122 	glitch_filt_status = !!(data & DS1343_EGFIL);
123 
124 	if (glitch_filt_status)
125 		return sprintf(buf, "enabled\n");
126 	else
127 		return sprintf(buf, "disabled\n");
128 }
129 
130 static ssize_t ds1343_store_glitchfilter(struct device *dev,
131 					struct device_attribute *attr,
132 					const char *buf, size_t count)
133 {
134 	struct ds1343_priv *priv = dev_get_drvdata(dev);
135 	int data;
136 
137 	regmap_read(priv->map, DS1343_CONTROL_REG, &data);
138 
139 	if (strncmp(buf, "enabled", 7) == 0)
140 		data |= DS1343_EGFIL;
141 
142 	else if (strncmp(buf, "disabled", 8) == 0)
143 		data &= ~(DS1343_EGFIL);
144 
145 	else
146 		return -EINVAL;
147 
148 	regmap_write(priv->map, DS1343_CONTROL_REG, data);
149 
150 	return count;
151 }
152 
153 static DEVICE_ATTR(glitch_filter, S_IRUGO | S_IWUSR, ds1343_show_glitchfilter,
154 			ds1343_store_glitchfilter);
155 
156 static ssize_t ds1343_nvram_write(struct file *filp, struct kobject *kobj,
157 			struct bin_attribute *attr,
158 			char *buf, loff_t off, size_t count)
159 {
160 	int ret;
161 	unsigned char address;
162 	struct device *dev = kobj_to_dev(kobj);
163 	struct ds1343_priv *priv = dev_get_drvdata(dev);
164 
165 	address = DS1343_NVRAM + off;
166 
167 	ret = regmap_bulk_write(priv->map, address, buf, count);
168 	if (ret < 0)
169 		dev_err(&priv->spi->dev, "Error in nvram write %d", ret);
170 
171 	return (ret < 0) ? ret : count;
172 }
173 
174 
175 static ssize_t ds1343_nvram_read(struct file *filp, struct kobject *kobj,
176 				struct bin_attribute *attr,
177 				char *buf, loff_t off, size_t count)
178 {
179 	int ret;
180 	unsigned char address;
181 	struct device *dev = kobj_to_dev(kobj);
182 	struct ds1343_priv *priv = dev_get_drvdata(dev);
183 
184 	address = DS1343_NVRAM + off;
185 
186 	ret = regmap_bulk_read(priv->map, address, buf, count);
187 	if (ret < 0)
188 		dev_err(&priv->spi->dev, "Error in nvram read %d\n", ret);
189 
190 	return (ret < 0) ? ret : count;
191 }
192 
193 
194 static struct bin_attribute nvram_attr = {
195 	.attr.name	= "nvram",
196 	.attr.mode	= S_IRUGO | S_IWUSR,
197 	.read		= ds1343_nvram_read,
198 	.write		= ds1343_nvram_write,
199 	.size		= DS1343_NVRAM_LEN,
200 };
201 
202 static ssize_t ds1343_show_alarmstatus(struct device *dev,
203 				struct device_attribute *attr, char *buf)
204 {
205 	struct ds1343_priv *priv = dev_get_drvdata(dev);
206 	int alarmstatus, data;
207 
208 	regmap_read(priv->map, DS1343_CONTROL_REG, &data);
209 
210 	alarmstatus = !!(data & DS1343_A0IE);
211 
212 	if (alarmstatus)
213 		return sprintf(buf, "enabled\n");
214 	else
215 		return sprintf(buf, "disabled\n");
216 }
217 
218 static DEVICE_ATTR(alarm_status, S_IRUGO, ds1343_show_alarmstatus, NULL);
219 
220 static ssize_t ds1343_show_alarmmode(struct device *dev,
221 				struct device_attribute *attr, char *buf)
222 {
223 	struct ds1343_priv *priv = dev_get_drvdata(dev);
224 	int alarm_mode, data;
225 	char *alarm_str;
226 
227 	regmap_read(priv->map, DS1343_ALM0_SEC_REG, &data);
228 	alarm_mode = (data & 0x80) >> 4;
229 
230 	regmap_read(priv->map, DS1343_ALM0_MIN_REG, &data);
231 	alarm_mode |= (data & 0x80) >> 5;
232 
233 	regmap_read(priv->map, DS1343_ALM0_HOUR_REG, &data);
234 	alarm_mode |= (data & 0x80) >> 6;
235 
236 	regmap_read(priv->map, DS1343_ALM0_DAY_REG, &data);
237 	alarm_mode |= (data & 0x80) >> 7;
238 
239 	switch (alarm_mode) {
240 	case 15:
241 		alarm_str = "each second";
242 		break;
243 
244 	case 7:
245 		alarm_str = "seconds match";
246 		break;
247 
248 	case 3:
249 		alarm_str = "minutes and seconds match";
250 		break;
251 
252 	case 1:
253 		alarm_str = "hours, minutes and seconds match";
254 		break;
255 
256 	case 0:
257 		alarm_str = "day, hours, minutes and seconds match";
258 		break;
259 
260 	default:
261 		alarm_str = "invalid";
262 		break;
263 	}
264 
265 	return sprintf(buf, "%s\n", alarm_str);
266 }
267 
268 static DEVICE_ATTR(alarm_mode, S_IRUGO, ds1343_show_alarmmode, NULL);
269 
270 static ssize_t ds1343_show_tricklecharger(struct device *dev,
271 				struct device_attribute *attr, char *buf)
272 {
273 	struct ds1343_priv *priv = dev_get_drvdata(dev);
274 	int data;
275 	char *diodes = "disabled", *resistors = " ";
276 
277 	regmap_read(priv->map, DS1343_TRICKLE_REG, &data);
278 
279 	if ((data & 0xf0) == DS1343_TRICKLE_MAGIC) {
280 		switch (data & 0x0c) {
281 		case DS1343_TRICKLE_DS1:
282 			diodes = "one diode,";
283 			break;
284 
285 		default:
286 			diodes = "no diode,";
287 			break;
288 		}
289 
290 		switch (data & 0x03) {
291 		case DS1343_TRICKLE_1K:
292 			resistors = "1k Ohm";
293 			break;
294 
295 		case DS1343_TRICKLE_2K:
296 			resistors = "2k Ohm";
297 			break;
298 
299 		case DS1343_TRICKLE_4K:
300 			resistors = "4k Ohm";
301 			break;
302 
303 		default:
304 			diodes = "disabled";
305 			break;
306 		}
307 	}
308 
309 	return sprintf(buf, "%s %s\n", diodes, resistors);
310 }
311 
312 static DEVICE_ATTR(trickle_charger, S_IRUGO, ds1343_show_tricklecharger, NULL);
313 
314 static int ds1343_sysfs_register(struct device *dev)
315 {
316 	struct ds1343_priv *priv = dev_get_drvdata(dev);
317 	int err;
318 
319 	err = device_create_file(dev, &dev_attr_glitch_filter);
320 	if (err)
321 		return err;
322 
323 	err = device_create_file(dev, &dev_attr_trickle_charger);
324 	if (err)
325 		goto error1;
326 
327 	err = device_create_bin_file(dev, &nvram_attr);
328 	if (err)
329 		goto error2;
330 
331 	if (priv->irq <= 0)
332 		return err;
333 
334 	err = device_create_file(dev, &dev_attr_alarm_mode);
335 	if (err)
336 		goto error3;
337 
338 	err = device_create_file(dev, &dev_attr_alarm_status);
339 	if (!err)
340 		return err;
341 
342 	device_remove_file(dev, &dev_attr_alarm_mode);
343 
344 error3:
345 	device_remove_bin_file(dev, &nvram_attr);
346 
347 error2:
348 	device_remove_file(dev, &dev_attr_trickle_charger);
349 
350 error1:
351 	device_remove_file(dev, &dev_attr_glitch_filter);
352 
353 	return err;
354 }
355 
356 static void ds1343_sysfs_unregister(struct device *dev)
357 {
358 	struct ds1343_priv *priv = dev_get_drvdata(dev);
359 
360 	device_remove_file(dev, &dev_attr_glitch_filter);
361 	device_remove_file(dev, &dev_attr_trickle_charger);
362 	device_remove_bin_file(dev, &nvram_attr);
363 
364 	if (priv->irq <= 0)
365 		return;
366 
367 	device_remove_file(dev, &dev_attr_alarm_status);
368 	device_remove_file(dev, &dev_attr_alarm_mode);
369 }
370 
371 static int ds1343_read_time(struct device *dev, struct rtc_time *dt)
372 {
373 	struct ds1343_priv *priv = dev_get_drvdata(dev);
374 	unsigned char buf[7];
375 	int res;
376 
377 	res = regmap_bulk_read(priv->map, DS1343_SECONDS_REG, buf, 7);
378 	if (res)
379 		return res;
380 
381 	dt->tm_sec	= bcd2bin(buf[0]);
382 	dt->tm_min	= bcd2bin(buf[1]);
383 	dt->tm_hour	= bcd2bin(buf[2] & 0x3F);
384 	dt->tm_wday	= bcd2bin(buf[3]) - 1;
385 	dt->tm_mday	= bcd2bin(buf[4]);
386 	dt->tm_mon	= bcd2bin(buf[5] & 0x1F) - 1;
387 	dt->tm_year	= bcd2bin(buf[6]) + 100; /* year offset from 1900 */
388 
389 	return rtc_valid_tm(dt);
390 }
391 
392 static int ds1343_set_time(struct device *dev, struct rtc_time *dt)
393 {
394 	struct ds1343_priv *priv = dev_get_drvdata(dev);
395 	int res;
396 
397 	res = regmap_write(priv->map, DS1343_SECONDS_REG,
398 				bin2bcd(dt->tm_sec));
399 	if (res)
400 		return res;
401 
402 	res = regmap_write(priv->map, DS1343_MINUTES_REG,
403 				bin2bcd(dt->tm_min));
404 	if (res)
405 		return res;
406 
407 	res = regmap_write(priv->map, DS1343_HOURS_REG,
408 				bin2bcd(dt->tm_hour) & 0x3F);
409 	if (res)
410 		return res;
411 
412 	res = regmap_write(priv->map, DS1343_DAY_REG,
413 				bin2bcd(dt->tm_wday + 1));
414 	if (res)
415 		return res;
416 
417 	res = regmap_write(priv->map, DS1343_DATE_REG,
418 				bin2bcd(dt->tm_mday));
419 	if (res)
420 		return res;
421 
422 	res = regmap_write(priv->map, DS1343_MONTH_REG,
423 				bin2bcd(dt->tm_mon + 1));
424 	if (res)
425 		return res;
426 
427 	dt->tm_year %= 100;
428 
429 	res = regmap_write(priv->map, DS1343_YEAR_REG,
430 				bin2bcd(dt->tm_year));
431 	if (res)
432 		return res;
433 
434 	return 0;
435 }
436 
437 static int ds1343_update_alarm(struct device *dev)
438 {
439 	struct ds1343_priv *priv = dev_get_drvdata(dev);
440 	unsigned int control, stat;
441 	unsigned char buf[4];
442 	int res = 0;
443 
444 	res = regmap_read(priv->map, DS1343_CONTROL_REG, &control);
445 	if (res)
446 		return res;
447 
448 	res = regmap_read(priv->map, DS1343_STATUS_REG, &stat);
449 	if (res)
450 		return res;
451 
452 	control &= ~(DS1343_A0IE);
453 	stat &= ~(DS1343_IRQF0);
454 
455 	res = regmap_write(priv->map, DS1343_CONTROL_REG, control);
456 	if (res)
457 		return res;
458 
459 	res = regmap_write(priv->map, DS1343_STATUS_REG, stat);
460 	if (res)
461 		return res;
462 
463 	buf[0] = priv->alarm_sec < 0 || (priv->irqen & RTC_UF) ?
464 		0x80 : bin2bcd(priv->alarm_sec) & 0x7F;
465 	buf[1] = priv->alarm_min < 0 || (priv->irqen & RTC_UF) ?
466 		0x80 : bin2bcd(priv->alarm_min) & 0x7F;
467 	buf[2] = priv->alarm_hour < 0 || (priv->irqen & RTC_UF) ?
468 		0x80 : bin2bcd(priv->alarm_hour) & 0x3F;
469 	buf[3] = priv->alarm_mday < 0 || (priv->irqen & RTC_UF) ?
470 		0x80 : bin2bcd(priv->alarm_mday) & 0x7F;
471 
472 	res = regmap_bulk_write(priv->map, DS1343_ALM0_SEC_REG, buf, 4);
473 	if (res)
474 		return res;
475 
476 	if (priv->irqen) {
477 		control |= DS1343_A0IE;
478 		res = regmap_write(priv->map, DS1343_CONTROL_REG, control);
479 	}
480 
481 	return res;
482 }
483 
484 static int ds1343_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
485 {
486 	struct ds1343_priv *priv = dev_get_drvdata(dev);
487 	int res = 0;
488 	unsigned int stat;
489 
490 	if (priv->irq <= 0)
491 		return -EINVAL;
492 
493 	mutex_lock(&priv->mutex);
494 
495 	res = regmap_read(priv->map, DS1343_STATUS_REG, &stat);
496 	if (res)
497 		goto out;
498 
499 	alarm->enabled = !!(priv->irqen & RTC_AF);
500 	alarm->pending = !!(stat & DS1343_IRQF0);
501 
502 	alarm->time.tm_sec = priv->alarm_sec < 0 ? 0 : priv->alarm_sec;
503 	alarm->time.tm_min = priv->alarm_min < 0 ? 0 : priv->alarm_min;
504 	alarm->time.tm_hour = priv->alarm_hour < 0 ? 0 : priv->alarm_hour;
505 	alarm->time.tm_mday = priv->alarm_mday < 0 ? 0 : priv->alarm_mday;
506 
507 	alarm->time.tm_mon = -1;
508 	alarm->time.tm_year = -1;
509 	alarm->time.tm_wday = -1;
510 	alarm->time.tm_yday = -1;
511 	alarm->time.tm_isdst = -1;
512 
513 out:
514 	mutex_unlock(&priv->mutex);
515 	return res;
516 }
517 
518 static int ds1343_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
519 {
520 	struct ds1343_priv *priv = dev_get_drvdata(dev);
521 	int res = 0;
522 
523 	if (priv->irq <= 0)
524 		return -EINVAL;
525 
526 	mutex_lock(&priv->mutex);
527 
528 	priv->alarm_sec = alarm->time.tm_sec;
529 	priv->alarm_min = alarm->time.tm_min;
530 	priv->alarm_hour = alarm->time.tm_hour;
531 	priv->alarm_mday = alarm->time.tm_mday;
532 
533 	if (alarm->enabled)
534 		priv->irqen |= RTC_AF;
535 
536 	res = ds1343_update_alarm(dev);
537 
538 	mutex_unlock(&priv->mutex);
539 
540 	return res;
541 }
542 
543 static int ds1343_alarm_irq_enable(struct device *dev, unsigned int enabled)
544 {
545 	struct ds1343_priv *priv = dev_get_drvdata(dev);
546 	int res = 0;
547 
548 	if (priv->irq <= 0)
549 		return -EINVAL;
550 
551 	mutex_lock(&priv->mutex);
552 
553 	if (enabled)
554 		priv->irqen |= RTC_AF;
555 	else
556 		priv->irqen &= ~RTC_AF;
557 
558 	res = ds1343_update_alarm(dev);
559 
560 	mutex_unlock(&priv->mutex);
561 
562 	return res;
563 }
564 
565 static irqreturn_t ds1343_thread(int irq, void *dev_id)
566 {
567 	struct ds1343_priv *priv = dev_id;
568 	unsigned int stat, control;
569 	int res = 0;
570 
571 	mutex_lock(&priv->mutex);
572 
573 	res = regmap_read(priv->map, DS1343_STATUS_REG, &stat);
574 	if (res)
575 		goto out;
576 
577 	if (stat & DS1343_IRQF0) {
578 		stat &= ~DS1343_IRQF0;
579 		regmap_write(priv->map, DS1343_STATUS_REG, stat);
580 
581 		res = regmap_read(priv->map, DS1343_CONTROL_REG, &control);
582 		if (res)
583 			goto out;
584 
585 		control &= ~DS1343_A0IE;
586 		regmap_write(priv->map, DS1343_CONTROL_REG, control);
587 
588 		rtc_update_irq(priv->rtc, 1, RTC_AF | RTC_IRQF);
589 	}
590 
591 out:
592 	mutex_unlock(&priv->mutex);
593 	return IRQ_HANDLED;
594 }
595 
596 static const struct rtc_class_ops ds1343_rtc_ops = {
597 	.ioctl		= ds1343_ioctl,
598 	.read_time	= ds1343_read_time,
599 	.set_time	= ds1343_set_time,
600 	.read_alarm	= ds1343_read_alarm,
601 	.set_alarm	= ds1343_set_alarm,
602 	.alarm_irq_enable = ds1343_alarm_irq_enable,
603 };
604 
605 static int ds1343_probe(struct spi_device *spi)
606 {
607 	struct ds1343_priv *priv;
608 	struct regmap_config config;
609 	unsigned int data;
610 	int res;
611 
612 	memset(&config, 0, sizeof(config));
613 	config.reg_bits = 8;
614 	config.val_bits = 8;
615 	config.write_flag_mask = 0x80;
616 
617 	priv = devm_kzalloc(&spi->dev, sizeof(struct ds1343_priv), GFP_KERNEL);
618 	if (!priv)
619 		return -ENOMEM;
620 
621 	priv->spi = spi;
622 	mutex_init(&priv->mutex);
623 
624 	/* RTC DS1347 works in spi mode 3 and
625 	 * its chip select is active high
626 	 */
627 	spi->mode = SPI_MODE_3 | SPI_CS_HIGH;
628 	spi->bits_per_word = 8;
629 	res = spi_setup(spi);
630 	if (res)
631 		return res;
632 
633 	spi_set_drvdata(spi, priv);
634 
635 	priv->map = devm_regmap_init_spi(spi, &config);
636 
637 	if (IS_ERR(priv->map)) {
638 		dev_err(&spi->dev, "spi regmap init failed for rtc ds1343\n");
639 		return PTR_ERR(priv->map);
640 	}
641 
642 	res = regmap_read(priv->map, DS1343_SECONDS_REG, &data);
643 	if (res)
644 		return res;
645 
646 	regmap_read(priv->map, DS1343_CONTROL_REG, &data);
647 	data |= DS1343_INTCN;
648 	data &= ~(DS1343_EOSC | DS1343_A1IE | DS1343_A0IE);
649 	regmap_write(priv->map, DS1343_CONTROL_REG, data);
650 
651 	regmap_read(priv->map, DS1343_STATUS_REG, &data);
652 	data &= ~(DS1343_OSF | DS1343_IRQF1 | DS1343_IRQF0);
653 	regmap_write(priv->map, DS1343_STATUS_REG, data);
654 
655 	priv->rtc = devm_rtc_device_register(&spi->dev, "ds1343",
656 					&ds1343_rtc_ops, THIS_MODULE);
657 	if (IS_ERR(priv->rtc)) {
658 		dev_err(&spi->dev, "unable to register rtc ds1343\n");
659 		return PTR_ERR(priv->rtc);
660 	}
661 
662 	priv->irq = spi->irq;
663 
664 	if (priv->irq >= 0) {
665 		res = devm_request_threaded_irq(&spi->dev, spi->irq, NULL,
666 						ds1343_thread,
667 						IRQF_NO_SUSPEND | IRQF_ONESHOT,
668 						"ds1343", priv);
669 		if (res) {
670 			priv->irq = -1;
671 			dev_err(&spi->dev,
672 				"unable to request irq for rtc ds1343\n");
673 		} else {
674 			device_set_wakeup_capable(&spi->dev, 1);
675 		}
676 	}
677 
678 	res = ds1343_sysfs_register(&spi->dev);
679 	if (res)
680 		dev_err(&spi->dev,
681 			"unable to create sysfs entries for rtc ds1343\n");
682 
683 	return 0;
684 }
685 
686 static int ds1343_remove(struct spi_device *spi)
687 {
688 	struct ds1343_priv *priv = spi_get_drvdata(spi);
689 
690 	if (spi->irq) {
691 		mutex_lock(&priv->mutex);
692 		priv->irqen &= ~RTC_AF;
693 		mutex_unlock(&priv->mutex);
694 
695 		devm_free_irq(&spi->dev, spi->irq, priv);
696 	}
697 
698 	spi_set_drvdata(spi, NULL);
699 
700 	ds1343_sysfs_unregister(&spi->dev);
701 
702 	return 0;
703 }
704 
705 #ifdef CONFIG_PM_SLEEP
706 
707 static int ds1343_suspend(struct device *dev)
708 {
709 	struct spi_device *spi = to_spi_device(dev);
710 
711 	if (spi->irq >= 0 && device_may_wakeup(dev))
712 		enable_irq_wake(spi->irq);
713 
714 	return 0;
715 }
716 
717 static int ds1343_resume(struct device *dev)
718 {
719 	struct spi_device *spi = to_spi_device(dev);
720 
721 	if (spi->irq >= 0 && device_may_wakeup(dev))
722 		disable_irq_wake(spi->irq);
723 
724 	return 0;
725 }
726 
727 #endif
728 
729 static SIMPLE_DEV_PM_OPS(ds1343_pm, ds1343_suspend, ds1343_resume);
730 
731 static struct spi_driver ds1343_driver = {
732 	.driver = {
733 		.name = "ds1343",
734 		.owner = THIS_MODULE,
735 		.pm = &ds1343_pm,
736 	},
737 	.probe = ds1343_probe,
738 	.remove = ds1343_remove,
739 	.id_table = ds1343_id,
740 };
741 
742 module_spi_driver(ds1343_driver);
743 
744 MODULE_DESCRIPTION("DS1343 RTC SPI Driver");
745 MODULE_AUTHOR("Raghavendra Chandra Ganiga <ravi23ganiga@gmail.com>,"
746 		"Ankur Srivastava <sankurece@gmail.com>");
747 MODULE_LICENSE("GPL v2");
748 MODULE_VERSION(DS1343_DRV_VERSION);
749