xref: /linux/drivers/rtc/rtc-s5m.c (revision 30e48a75df9c6ead93866bdf1511ca6ecfe17fbe)
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // Copyright (c) 2013-2014 Samsung Electronics Co., Ltd
4 //	http://www.samsung.com
5 //
6 //  Copyright (C) 2013 Google, Inc
7 
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9 
10 #include <linux/module.h>
11 #include <linux/i2c.h>
12 #include <linux/bcd.h>
13 #include <linux/regmap.h>
14 #include <linux/rtc.h>
15 #include <linux/platform_device.h>
16 #include <linux/mfd/samsung/core.h>
17 #include <linux/mfd/samsung/irq.h>
18 #include <linux/mfd/samsung/rtc.h>
19 #include <linux/mfd/samsung/s2mps14.h>
20 
21 /*
22  * Maximum number of retries for checking changes in UDR field
23  * of S5M_RTC_UDR_CON register (to limit possible endless loop).
24  *
25  * After writing to RTC registers (setting time or alarm) read the UDR field
26  * in S5M_RTC_UDR_CON register. UDR is auto-cleared when data have
27  * been transferred.
28  */
29 #define UDR_READ_RETRY_CNT	5
30 
31 enum {
32 	RTC_SEC = 0,
33 	RTC_MIN,
34 	RTC_HOUR,
35 	RTC_WEEKDAY,
36 	RTC_DATE,
37 	RTC_MONTH,
38 	RTC_YEAR1,
39 	RTC_YEAR2,
40 	/* Make sure this is always the last enum name. */
41 	RTC_MAX_NUM_TIME_REGS
42 };
43 
44 /*
45  * Registers used by the driver which are different between chipsets.
46  *
47  * Operations like read time and write alarm/time require updating
48  * specific fields in UDR register. These fields usually are auto-cleared
49  * (with some exceptions).
50  *
51  * Table of operations per device:
52  *
53  * Device     | Write time | Read time | Write alarm
54  * =================================================
55  * S5M8767    | UDR + TIME |           | UDR
56  * S2MPS11/14 | WUDR       | RUDR      | WUDR + RUDR
57  * S2MPS13    | WUDR       | RUDR      | WUDR + AUDR
58  * S2MPS15    | WUDR       | RUDR      | AUDR
59  */
60 struct s5m_rtc_reg_config {
61 	/* Number of registers used for setting time/alarm0/alarm1 */
62 	unsigned int regs_count;
63 	/* First register for time, seconds */
64 	unsigned int time;
65 	/* RTC control register */
66 	unsigned int ctrl;
67 	/* First register for alarm 0, seconds */
68 	unsigned int alarm0;
69 	/* First register for alarm 1, seconds */
70 	unsigned int alarm1;
71 	/*
72 	 * Register for update flag (UDR). Typically setting UDR field to 1
73 	 * will enable update of time or alarm register. Then it will be
74 	 * auto-cleared after successful update.
75 	 */
76 	unsigned int udr_update;
77 	/* Auto-cleared mask in UDR field for writing time and alarm */
78 	unsigned int autoclear_udr_mask;
79 	/*
80 	 * Masks in UDR field for time and alarm operations.
81 	 * The read time mask can be 0. Rest should not.
82 	 */
83 	unsigned int read_time_udr_mask;
84 	unsigned int write_time_udr_mask;
85 	unsigned int write_alarm_udr_mask;
86 };
87 
88 /* Register map for S5M8767 */
89 static const struct s5m_rtc_reg_config s5m_rtc_regs = {
90 	.regs_count		= 8,
91 	.time			= S5M_RTC_SEC,
92 	.ctrl			= S5M_ALARM1_CONF,
93 	.alarm0			= S5M_ALARM0_SEC,
94 	.alarm1			= S5M_ALARM1_SEC,
95 	.udr_update		= S5M_RTC_UDR_CON,
96 	.autoclear_udr_mask	= S5M_RTC_UDR_MASK,
97 	.read_time_udr_mask	= 0, /* Not needed */
98 	.write_time_udr_mask	= S5M_RTC_UDR_MASK | S5M_RTC_TIME_EN_MASK,
99 	.write_alarm_udr_mask	= S5M_RTC_UDR_MASK,
100 };
101 
102 /* Register map for S2MPS13 */
103 static const struct s5m_rtc_reg_config s2mps13_rtc_regs = {
104 	.regs_count		= 7,
105 	.time			= S2MPS_RTC_SEC,
106 	.ctrl			= S2MPS_RTC_CTRL,
107 	.alarm0			= S2MPS_ALARM0_SEC,
108 	.alarm1			= S2MPS_ALARM1_SEC,
109 	.udr_update		= S2MPS_RTC_UDR_CON,
110 	.autoclear_udr_mask	= S2MPS_RTC_WUDR_MASK,
111 	.read_time_udr_mask	= S2MPS_RTC_RUDR_MASK,
112 	.write_time_udr_mask	= S2MPS_RTC_WUDR_MASK,
113 	.write_alarm_udr_mask	= S2MPS_RTC_WUDR_MASK | S2MPS13_RTC_AUDR_MASK,
114 };
115 
116 /* Register map for S2MPS11/14 */
117 static const struct s5m_rtc_reg_config s2mps14_rtc_regs = {
118 	.regs_count		= 7,
119 	.time			= S2MPS_RTC_SEC,
120 	.ctrl			= S2MPS_RTC_CTRL,
121 	.alarm0			= S2MPS_ALARM0_SEC,
122 	.alarm1			= S2MPS_ALARM1_SEC,
123 	.udr_update		= S2MPS_RTC_UDR_CON,
124 	.autoclear_udr_mask	= S2MPS_RTC_WUDR_MASK,
125 	.read_time_udr_mask	= S2MPS_RTC_RUDR_MASK,
126 	.write_time_udr_mask	= S2MPS_RTC_WUDR_MASK,
127 	.write_alarm_udr_mask	= S2MPS_RTC_WUDR_MASK | S2MPS_RTC_RUDR_MASK,
128 };
129 
130 /*
131  * Register map for S2MPS15 - in comparison to S2MPS14 the WUDR and AUDR bits
132  * are swapped.
133  */
134 static const struct s5m_rtc_reg_config s2mps15_rtc_regs = {
135 	.regs_count		= 7,
136 	.time			= S2MPS_RTC_SEC,
137 	.ctrl			= S2MPS_RTC_CTRL,
138 	.alarm0			= S2MPS_ALARM0_SEC,
139 	.alarm1			= S2MPS_ALARM1_SEC,
140 	.udr_update		= S2MPS_RTC_UDR_CON,
141 	.autoclear_udr_mask	= S2MPS_RTC_WUDR_MASK,
142 	.read_time_udr_mask	= S2MPS_RTC_RUDR_MASK,
143 	.write_time_udr_mask	= S2MPS15_RTC_WUDR_MASK,
144 	.write_alarm_udr_mask	= S2MPS15_RTC_AUDR_MASK,
145 };
146 
147 struct s5m_rtc_info {
148 	struct device *dev;
149 	struct i2c_client *i2c;
150 	struct sec_pmic_dev *s5m87xx;
151 	struct regmap *regmap;
152 	struct rtc_device *rtc_dev;
153 	int irq;
154 	enum sec_device_type device_type;
155 	int rtc_24hr_mode;
156 	const struct s5m_rtc_reg_config	*regs;
157 };
158 
159 static const struct regmap_config s5m_rtc_regmap_config = {
160 	.reg_bits = 8,
161 	.val_bits = 8,
162 
163 	.max_register = S5M_RTC_REG_MAX,
164 };
165 
166 static const struct regmap_config s2mps14_rtc_regmap_config = {
167 	.reg_bits = 8,
168 	.val_bits = 8,
169 
170 	.max_register = S2MPS_RTC_REG_MAX,
171 };
172 
173 static void s5m8767_data_to_tm(u8 *data, struct rtc_time *tm,
174 			       int rtc_24hr_mode)
175 {
176 	tm->tm_sec = data[RTC_SEC] & 0x7f;
177 	tm->tm_min = data[RTC_MIN] & 0x7f;
178 	if (rtc_24hr_mode) {
179 		tm->tm_hour = data[RTC_HOUR] & 0x1f;
180 	} else {
181 		tm->tm_hour = data[RTC_HOUR] & 0x0f;
182 		if (data[RTC_HOUR] & HOUR_PM_MASK)
183 			tm->tm_hour += 12;
184 	}
185 
186 	tm->tm_wday = ffs(data[RTC_WEEKDAY] & 0x7f);
187 	tm->tm_mday = data[RTC_DATE] & 0x1f;
188 	tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1;
189 	tm->tm_year = (data[RTC_YEAR1] & 0x7f) + 100;
190 	tm->tm_yday = 0;
191 	tm->tm_isdst = 0;
192 }
193 
194 static int s5m8767_tm_to_data(struct rtc_time *tm, u8 *data)
195 {
196 	data[RTC_SEC] = tm->tm_sec;
197 	data[RTC_MIN] = tm->tm_min;
198 
199 	if (tm->tm_hour >= 12)
200 		data[RTC_HOUR] = tm->tm_hour | HOUR_PM_MASK;
201 	else
202 		data[RTC_HOUR] = tm->tm_hour & ~HOUR_PM_MASK;
203 
204 	data[RTC_WEEKDAY] = 1 << tm->tm_wday;
205 	data[RTC_DATE] = tm->tm_mday;
206 	data[RTC_MONTH] = tm->tm_mon + 1;
207 	data[RTC_YEAR1] = tm->tm_year - 100;
208 
209 	return 0;
210 }
211 
212 /*
213  * Read RTC_UDR_CON register and wait till UDR field is cleared.
214  * This indicates that time/alarm update ended.
215  */
216 static int s5m8767_wait_for_udr_update(struct s5m_rtc_info *info)
217 {
218 	int ret, retry = UDR_READ_RETRY_CNT;
219 	unsigned int data;
220 
221 	do {
222 		ret = regmap_read(info->regmap, info->regs->udr_update, &data);
223 	} while (--retry && (data & info->regs->autoclear_udr_mask) && !ret);
224 
225 	if (!retry)
226 		dev_err(info->dev, "waiting for UDR update, reached max number of retries\n");
227 
228 	return ret;
229 }
230 
231 static int s5m_check_peding_alarm_interrupt(struct s5m_rtc_info *info,
232 		struct rtc_wkalrm *alarm)
233 {
234 	int ret;
235 	unsigned int val;
236 
237 	switch (info->device_type) {
238 	case S5M8767X:
239 		ret = regmap_read(info->regmap, S5M_RTC_STATUS, &val);
240 		val &= S5M_ALARM0_STATUS;
241 		break;
242 	case S2MPS15X:
243 	case S2MPS14X:
244 	case S2MPS13X:
245 		ret = regmap_read(info->s5m87xx->regmap_pmic, S2MPS14_REG_ST2,
246 				&val);
247 		val &= S2MPS_ALARM0_STATUS;
248 		break;
249 	default:
250 		return -EINVAL;
251 	}
252 	if (ret < 0)
253 		return ret;
254 
255 	if (val)
256 		alarm->pending = 1;
257 	else
258 		alarm->pending = 0;
259 
260 	return 0;
261 }
262 
263 static int s5m8767_rtc_set_time_reg(struct s5m_rtc_info *info)
264 {
265 	int ret;
266 	unsigned int data;
267 
268 	ret = regmap_read(info->regmap, info->regs->udr_update, &data);
269 	if (ret < 0) {
270 		dev_err(info->dev, "failed to read update reg(%d)\n", ret);
271 		return ret;
272 	}
273 
274 	data |= info->regs->write_time_udr_mask;
275 
276 	ret = regmap_write(info->regmap, info->regs->udr_update, data);
277 	if (ret < 0) {
278 		dev_err(info->dev, "failed to write update reg(%d)\n", ret);
279 		return ret;
280 	}
281 
282 	ret = s5m8767_wait_for_udr_update(info);
283 
284 	return ret;
285 }
286 
287 static int s5m8767_rtc_set_alarm_reg(struct s5m_rtc_info *info)
288 {
289 	int ret;
290 	unsigned int data;
291 
292 	ret = regmap_read(info->regmap, info->regs->udr_update, &data);
293 	if (ret < 0) {
294 		dev_err(info->dev, "%s: fail to read update reg(%d)\n",
295 			__func__, ret);
296 		return ret;
297 	}
298 
299 	data |= info->regs->write_alarm_udr_mask;
300 	switch (info->device_type) {
301 	case S5M8767X:
302 		data &= ~S5M_RTC_TIME_EN_MASK;
303 		break;
304 	case S2MPS15X:
305 	case S2MPS14X:
306 	case S2MPS13X:
307 		/* No exceptions needed */
308 		break;
309 	default:
310 		return -EINVAL;
311 	}
312 
313 	ret = regmap_write(info->regmap, info->regs->udr_update, data);
314 	if (ret < 0) {
315 		dev_err(info->dev, "%s: fail to write update reg(%d)\n",
316 			__func__, ret);
317 		return ret;
318 	}
319 
320 	ret = s5m8767_wait_for_udr_update(info);
321 
322 	/* On S2MPS13 the AUDR is not auto-cleared */
323 	if (info->device_type == S2MPS13X)
324 		regmap_update_bits(info->regmap, info->regs->udr_update,
325 				   S2MPS13_RTC_AUDR_MASK, 0);
326 
327 	return ret;
328 }
329 
330 static int s5m_rtc_read_time(struct device *dev, struct rtc_time *tm)
331 {
332 	struct s5m_rtc_info *info = dev_get_drvdata(dev);
333 	u8 data[RTC_MAX_NUM_TIME_REGS];
334 	int ret;
335 
336 	if (info->regs->read_time_udr_mask) {
337 		ret = regmap_update_bits(info->regmap,
338 				info->regs->udr_update,
339 				info->regs->read_time_udr_mask,
340 				info->regs->read_time_udr_mask);
341 		if (ret) {
342 			dev_err(dev,
343 				"Failed to prepare registers for time reading: %d\n",
344 				ret);
345 			return ret;
346 		}
347 	}
348 	ret = regmap_bulk_read(info->regmap, info->regs->time, data,
349 			info->regs->regs_count);
350 	if (ret < 0)
351 		return ret;
352 
353 	switch (info->device_type) {
354 	case S5M8767X:
355 	case S2MPS15X:
356 	case S2MPS14X:
357 	case S2MPS13X:
358 		s5m8767_data_to_tm(data, tm, info->rtc_24hr_mode);
359 		break;
360 
361 	default:
362 		return -EINVAL;
363 	}
364 
365 	dev_dbg(dev, "%s: %ptR(%d)\n", __func__, tm, tm->tm_wday);
366 
367 	return 0;
368 }
369 
370 static int s5m_rtc_set_time(struct device *dev, struct rtc_time *tm)
371 {
372 	struct s5m_rtc_info *info = dev_get_drvdata(dev);
373 	u8 data[RTC_MAX_NUM_TIME_REGS];
374 	int ret = 0;
375 
376 	switch (info->device_type) {
377 	case S5M8767X:
378 	case S2MPS15X:
379 	case S2MPS14X:
380 	case S2MPS13X:
381 		ret = s5m8767_tm_to_data(tm, data);
382 		break;
383 	default:
384 		return -EINVAL;
385 	}
386 
387 	if (ret < 0)
388 		return ret;
389 
390 	dev_dbg(dev, "%s: %ptR(%d)\n", __func__, tm, tm->tm_wday);
391 
392 	ret = regmap_raw_write(info->regmap, info->regs->time, data,
393 			info->regs->regs_count);
394 	if (ret < 0)
395 		return ret;
396 
397 	ret = s5m8767_rtc_set_time_reg(info);
398 
399 	return ret;
400 }
401 
402 static int s5m_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
403 {
404 	struct s5m_rtc_info *info = dev_get_drvdata(dev);
405 	u8 data[RTC_MAX_NUM_TIME_REGS];
406 	int ret, i;
407 
408 	ret = regmap_bulk_read(info->regmap, info->regs->alarm0, data,
409 			info->regs->regs_count);
410 	if (ret < 0)
411 		return ret;
412 
413 	switch (info->device_type) {
414 	case S5M8767X:
415 	case S2MPS15X:
416 	case S2MPS14X:
417 	case S2MPS13X:
418 		s5m8767_data_to_tm(data, &alrm->time, info->rtc_24hr_mode);
419 		alrm->enabled = 0;
420 		for (i = 0; i < info->regs->regs_count; i++) {
421 			if (data[i] & ALARM_ENABLE_MASK) {
422 				alrm->enabled = 1;
423 				break;
424 			}
425 		}
426 		break;
427 
428 	default:
429 		return -EINVAL;
430 	}
431 
432 	dev_dbg(dev, "%s: %ptR(%d)\n", __func__, &alrm->time, alrm->time.tm_wday);
433 
434 	return s5m_check_peding_alarm_interrupt(info, alrm);
435 }
436 
437 static int s5m_rtc_stop_alarm(struct s5m_rtc_info *info)
438 {
439 	u8 data[RTC_MAX_NUM_TIME_REGS];
440 	int ret, i;
441 	struct rtc_time tm;
442 
443 	ret = regmap_bulk_read(info->regmap, info->regs->alarm0, data,
444 			info->regs->regs_count);
445 	if (ret < 0)
446 		return ret;
447 
448 	s5m8767_data_to_tm(data, &tm, info->rtc_24hr_mode);
449 	dev_dbg(info->dev, "%s: %ptR(%d)\n", __func__, &tm, tm.tm_wday);
450 
451 	switch (info->device_type) {
452 	case S5M8767X:
453 	case S2MPS15X:
454 	case S2MPS14X:
455 	case S2MPS13X:
456 		for (i = 0; i < info->regs->regs_count; i++)
457 			data[i] &= ~ALARM_ENABLE_MASK;
458 
459 		ret = regmap_raw_write(info->regmap, info->regs->alarm0, data,
460 				info->regs->regs_count);
461 		if (ret < 0)
462 			return ret;
463 
464 		ret = s5m8767_rtc_set_alarm_reg(info);
465 
466 		break;
467 
468 	default:
469 		return -EINVAL;
470 	}
471 
472 	return ret;
473 }
474 
475 static int s5m_rtc_start_alarm(struct s5m_rtc_info *info)
476 {
477 	int ret;
478 	u8 data[RTC_MAX_NUM_TIME_REGS];
479 	struct rtc_time tm;
480 
481 	ret = regmap_bulk_read(info->regmap, info->regs->alarm0, data,
482 			info->regs->regs_count);
483 	if (ret < 0)
484 		return ret;
485 
486 	s5m8767_data_to_tm(data, &tm, info->rtc_24hr_mode);
487 	dev_dbg(info->dev, "%s: %ptR(%d)\n", __func__, &tm, tm.tm_wday);
488 
489 	switch (info->device_type) {
490 	case S5M8767X:
491 	case S2MPS15X:
492 	case S2MPS14X:
493 	case S2MPS13X:
494 		data[RTC_SEC] |= ALARM_ENABLE_MASK;
495 		data[RTC_MIN] |= ALARM_ENABLE_MASK;
496 		data[RTC_HOUR] |= ALARM_ENABLE_MASK;
497 		data[RTC_WEEKDAY] &= ~ALARM_ENABLE_MASK;
498 		if (data[RTC_DATE] & 0x1f)
499 			data[RTC_DATE] |= ALARM_ENABLE_MASK;
500 		if (data[RTC_MONTH] & 0xf)
501 			data[RTC_MONTH] |= ALARM_ENABLE_MASK;
502 		if (data[RTC_YEAR1] & 0x7f)
503 			data[RTC_YEAR1] |= ALARM_ENABLE_MASK;
504 
505 		ret = regmap_raw_write(info->regmap, info->regs->alarm0, data,
506 				info->regs->regs_count);
507 		if (ret < 0)
508 			return ret;
509 		ret = s5m8767_rtc_set_alarm_reg(info);
510 
511 		break;
512 
513 	default:
514 		return -EINVAL;
515 	}
516 
517 	return ret;
518 }
519 
520 static int s5m_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
521 {
522 	struct s5m_rtc_info *info = dev_get_drvdata(dev);
523 	u8 data[RTC_MAX_NUM_TIME_REGS];
524 	int ret;
525 
526 	switch (info->device_type) {
527 	case S5M8767X:
528 	case S2MPS15X:
529 	case S2MPS14X:
530 	case S2MPS13X:
531 		s5m8767_tm_to_data(&alrm->time, data);
532 		break;
533 
534 	default:
535 		return -EINVAL;
536 	}
537 
538 	dev_dbg(dev, "%s: %ptR(%d)\n", __func__, &alrm->time, alrm->time.tm_wday);
539 
540 	ret = s5m_rtc_stop_alarm(info);
541 	if (ret < 0)
542 		return ret;
543 
544 	ret = regmap_raw_write(info->regmap, info->regs->alarm0, data,
545 			info->regs->regs_count);
546 	if (ret < 0)
547 		return ret;
548 
549 	ret = s5m8767_rtc_set_alarm_reg(info);
550 	if (ret < 0)
551 		return ret;
552 
553 	if (alrm->enabled)
554 		ret = s5m_rtc_start_alarm(info);
555 
556 	return ret;
557 }
558 
559 static int s5m_rtc_alarm_irq_enable(struct device *dev,
560 				    unsigned int enabled)
561 {
562 	struct s5m_rtc_info *info = dev_get_drvdata(dev);
563 
564 	if (enabled)
565 		return s5m_rtc_start_alarm(info);
566 	else
567 		return s5m_rtc_stop_alarm(info);
568 }
569 
570 static irqreturn_t s5m_rtc_alarm_irq(int irq, void *data)
571 {
572 	struct s5m_rtc_info *info = data;
573 
574 	rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
575 
576 	return IRQ_HANDLED;
577 }
578 
579 static const struct rtc_class_ops s5m_rtc_ops = {
580 	.read_time = s5m_rtc_read_time,
581 	.set_time = s5m_rtc_set_time,
582 	.read_alarm = s5m_rtc_read_alarm,
583 	.set_alarm = s5m_rtc_set_alarm,
584 	.alarm_irq_enable = s5m_rtc_alarm_irq_enable,
585 };
586 
587 static int s5m8767_rtc_init_reg(struct s5m_rtc_info *info)
588 {
589 	u8 data[2];
590 	int ret;
591 
592 	switch (info->device_type) {
593 	case S5M8767X:
594 		/* UDR update time. Default of 7.32 ms is too long. */
595 		ret = regmap_update_bits(info->regmap, S5M_RTC_UDR_CON,
596 				S5M_RTC_UDR_T_MASK, S5M_RTC_UDR_T_450_US);
597 		if (ret < 0)
598 			dev_err(info->dev, "%s: fail to change UDR time: %d\n",
599 					__func__, ret);
600 
601 		/* Set RTC control register : Binary mode, 24hour mode */
602 		data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
603 		data[1] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
604 
605 		ret = regmap_raw_write(info->regmap, S5M_ALARM0_CONF, data, 2);
606 		break;
607 
608 	case S2MPS15X:
609 	case S2MPS14X:
610 	case S2MPS13X:
611 		data[0] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
612 		ret = regmap_write(info->regmap, info->regs->ctrl, data[0]);
613 		if (ret < 0)
614 			break;
615 
616 		/*
617 		 * Should set WUDR & (RUDR or AUDR) bits to high after writing
618 		 * RTC_CTRL register like writing Alarm registers. We can't find
619 		 * the description from datasheet but vendor code does that
620 		 * really.
621 		 */
622 		ret = s5m8767_rtc_set_alarm_reg(info);
623 		break;
624 
625 	default:
626 		return -EINVAL;
627 	}
628 
629 	info->rtc_24hr_mode = 1;
630 	if (ret < 0) {
631 		dev_err(info->dev, "%s: fail to write controlm reg(%d)\n",
632 			__func__, ret);
633 		return ret;
634 	}
635 
636 	return ret;
637 }
638 
639 static int s5m_rtc_probe(struct platform_device *pdev)
640 {
641 	struct sec_pmic_dev *s5m87xx = dev_get_drvdata(pdev->dev.parent);
642 	struct s5m_rtc_info *info;
643 	const struct regmap_config *regmap_cfg;
644 	int ret, alarm_irq;
645 
646 	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
647 	if (!info)
648 		return -ENOMEM;
649 
650 	switch (platform_get_device_id(pdev)->driver_data) {
651 	case S2MPS15X:
652 		regmap_cfg = &s2mps14_rtc_regmap_config;
653 		info->regs = &s2mps15_rtc_regs;
654 		alarm_irq = S2MPS14_IRQ_RTCA0;
655 		break;
656 	case S2MPS14X:
657 		regmap_cfg = &s2mps14_rtc_regmap_config;
658 		info->regs = &s2mps14_rtc_regs;
659 		alarm_irq = S2MPS14_IRQ_RTCA0;
660 		break;
661 	case S2MPS13X:
662 		regmap_cfg = &s2mps14_rtc_regmap_config;
663 		info->regs = &s2mps13_rtc_regs;
664 		alarm_irq = S2MPS14_IRQ_RTCA0;
665 		break;
666 	case S5M8767X:
667 		regmap_cfg = &s5m_rtc_regmap_config;
668 		info->regs = &s5m_rtc_regs;
669 		alarm_irq = S5M8767_IRQ_RTCA1;
670 		break;
671 	default:
672 		dev_err(&pdev->dev,
673 				"Device type %lu is not supported by RTC driver\n",
674 				platform_get_device_id(pdev)->driver_data);
675 		return -ENODEV;
676 	}
677 
678 	info->i2c = devm_i2c_new_dummy_device(&pdev->dev, s5m87xx->i2c->adapter,
679 					      RTC_I2C_ADDR);
680 	if (IS_ERR(info->i2c)) {
681 		dev_err(&pdev->dev, "Failed to allocate I2C for RTC\n");
682 		return PTR_ERR(info->i2c);
683 	}
684 
685 	info->regmap = devm_regmap_init_i2c(info->i2c, regmap_cfg);
686 	if (IS_ERR(info->regmap)) {
687 		ret = PTR_ERR(info->regmap);
688 		dev_err(&pdev->dev, "Failed to allocate RTC register map: %d\n",
689 				ret);
690 		return ret;
691 	}
692 
693 	info->dev = &pdev->dev;
694 	info->s5m87xx = s5m87xx;
695 	info->device_type = platform_get_device_id(pdev)->driver_data;
696 
697 	if (s5m87xx->irq_data) {
698 		info->irq = regmap_irq_get_virq(s5m87xx->irq_data, alarm_irq);
699 		if (info->irq <= 0) {
700 			dev_err(&pdev->dev, "Failed to get virtual IRQ %d\n",
701 				alarm_irq);
702 			return -EINVAL;
703 		}
704 	}
705 
706 	platform_set_drvdata(pdev, info);
707 
708 	ret = s5m8767_rtc_init_reg(info);
709 	if (ret)
710 		return ret;
711 
712 	info->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
713 	if (IS_ERR(info->rtc_dev))
714 		return PTR_ERR(info->rtc_dev);
715 
716 	info->rtc_dev->ops = &s5m_rtc_ops;
717 
718 	info->rtc_dev->range_min = RTC_TIMESTAMP_BEGIN_2000;
719 	info->rtc_dev->range_max = RTC_TIMESTAMP_END_2099;
720 
721 	if (!info->irq) {
722 		clear_bit(RTC_FEATURE_ALARM, info->rtc_dev->features);
723 	} else {
724 		ret = devm_request_threaded_irq(&pdev->dev, info->irq, NULL,
725 						s5m_rtc_alarm_irq, 0, "rtc-alarm0",
726 						info);
727 		if (ret < 0) {
728 			dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
729 				info->irq, ret);
730 			return ret;
731 		}
732 		device_init_wakeup(&pdev->dev, 1);
733 	}
734 
735 	return devm_rtc_register_device(info->rtc_dev);
736 }
737 
738 #ifdef CONFIG_PM_SLEEP
739 static int s5m_rtc_resume(struct device *dev)
740 {
741 	struct s5m_rtc_info *info = dev_get_drvdata(dev);
742 	int ret = 0;
743 
744 	if (info->irq && device_may_wakeup(dev))
745 		ret = disable_irq_wake(info->irq);
746 
747 	return ret;
748 }
749 
750 static int s5m_rtc_suspend(struct device *dev)
751 {
752 	struct s5m_rtc_info *info = dev_get_drvdata(dev);
753 	int ret = 0;
754 
755 	if (info->irq && device_may_wakeup(dev))
756 		ret = enable_irq_wake(info->irq);
757 
758 	return ret;
759 }
760 #endif /* CONFIG_PM_SLEEP */
761 
762 static SIMPLE_DEV_PM_OPS(s5m_rtc_pm_ops, s5m_rtc_suspend, s5m_rtc_resume);
763 
764 static const struct platform_device_id s5m_rtc_id[] = {
765 	{ "s5m-rtc",		S5M8767X },
766 	{ "s2mps13-rtc",	S2MPS13X },
767 	{ "s2mps14-rtc",	S2MPS14X },
768 	{ "s2mps15-rtc",	S2MPS15X },
769 	{ },
770 };
771 MODULE_DEVICE_TABLE(platform, s5m_rtc_id);
772 
773 static struct platform_driver s5m_rtc_driver = {
774 	.driver		= {
775 		.name	= "s5m-rtc",
776 		.pm	= &s5m_rtc_pm_ops,
777 	},
778 	.probe		= s5m_rtc_probe,
779 	.id_table	= s5m_rtc_id,
780 };
781 
782 module_platform_driver(s5m_rtc_driver);
783 
784 /* Module information */
785 MODULE_AUTHOR("Sangbeom Kim <sbkim73@samsung.com>");
786 MODULE_DESCRIPTION("Samsung S5M/S2MPS14 RTC driver");
787 MODULE_LICENSE("GPL");
788