xref: /openbmc/linux/drivers/rtc/rtc-max77686.c (revision 8730046c)
1 /*
2  * RTC driver for Maxim MAX77686 and MAX77802
3  *
4  * Copyright (C) 2012 Samsung Electronics Co.Ltd
5  *
6  *  based on rtc-max8997.c
7  *
8  *  This program is free software; you can redistribute  it and/or modify it
9  *  under  the terms of  the GNU General  Public License as published by the
10  *  Free Software Foundation;  either version 2 of the  License, or (at your
11  *  option) any later version.
12  *
13  */
14 
15 #include <linux/i2c.h>
16 #include <linux/slab.h>
17 #include <linux/rtc.h>
18 #include <linux/delay.h>
19 #include <linux/mutex.h>
20 #include <linux/module.h>
21 #include <linux/platform_device.h>
22 #include <linux/mfd/max77686-private.h>
23 #include <linux/irqdomain.h>
24 #include <linux/regmap.h>
25 
26 #define MAX77686_I2C_ADDR_RTC		(0x0C >> 1)
27 #define MAX77620_I2C_ADDR_RTC		0x68
28 #define MAX77686_INVALID_I2C_ADDR	(-1)
29 
30 /* Define non existing register */
31 #define MAX77686_INVALID_REG		(-1)
32 
33 /* RTC Control Register */
34 #define BCD_EN_SHIFT			0
35 #define BCD_EN_MASK			BIT(BCD_EN_SHIFT)
36 #define MODEL24_SHIFT			1
37 #define MODEL24_MASK			BIT(MODEL24_SHIFT)
38 /* RTC Update Register1 */
39 #define RTC_UDR_SHIFT			0
40 #define RTC_UDR_MASK			BIT(RTC_UDR_SHIFT)
41 #define RTC_RBUDR_SHIFT			4
42 #define RTC_RBUDR_MASK			BIT(RTC_RBUDR_SHIFT)
43 /* RTC Hour register */
44 #define HOUR_PM_SHIFT			6
45 #define HOUR_PM_MASK			BIT(HOUR_PM_SHIFT)
46 /* RTC Alarm Enable */
47 #define ALARM_ENABLE_SHIFT		7
48 #define ALARM_ENABLE_MASK		BIT(ALARM_ENABLE_SHIFT)
49 
50 #define REG_RTC_NONE			0xdeadbeef
51 
52 /*
53  * MAX77802 has separate register (RTCAE1) for alarm enable instead
54  * using 1 bit from registers RTC{SEC,MIN,HOUR,DAY,MONTH,YEAR,DATE}
55  * as in done in MAX77686.
56  */
57 #define MAX77802_ALARM_ENABLE_VALUE	0x77
58 
59 enum {
60 	RTC_SEC = 0,
61 	RTC_MIN,
62 	RTC_HOUR,
63 	RTC_WEEKDAY,
64 	RTC_MONTH,
65 	RTC_YEAR,
66 	RTC_DATE,
67 	RTC_NR_TIME
68 };
69 
70 struct max77686_rtc_driver_data {
71 	/* Minimum usecs needed for a RTC update */
72 	unsigned long		delay;
73 	/* Mask used to read RTC registers value */
74 	u8			mask;
75 	/* Registers offset to I2C addresses map */
76 	const unsigned int	*map;
77 	/* Has a separate alarm enable register? */
78 	bool			alarm_enable_reg;
79 	/* I2C address for RTC block */
80 	int			rtc_i2c_addr;
81 	/* RTC interrupt via platform resource */
82 	bool			rtc_irq_from_platform;
83 	/* Pending alarm status register */
84 	int			alarm_pending_status_reg;
85 	/* RTC IRQ CHIP for regmap */
86 	const struct regmap_irq_chip *rtc_irq_chip;
87 };
88 
89 struct max77686_rtc_info {
90 	struct device		*dev;
91 	struct i2c_client	*rtc;
92 	struct rtc_device	*rtc_dev;
93 	struct mutex		lock;
94 
95 	struct regmap		*regmap;
96 	struct regmap		*rtc_regmap;
97 
98 	const struct max77686_rtc_driver_data *drv_data;
99 	struct regmap_irq_chip_data *rtc_irq_data;
100 
101 	int rtc_irq;
102 	int virq;
103 	int rtc_24hr_mode;
104 };
105 
106 enum MAX77686_RTC_OP {
107 	MAX77686_RTC_WRITE,
108 	MAX77686_RTC_READ,
109 };
110 
111 /* These are not registers but just offsets that are mapped to addresses */
112 enum max77686_rtc_reg_offset {
113 	REG_RTC_CONTROLM = 0,
114 	REG_RTC_CONTROL,
115 	REG_RTC_UPDATE0,
116 	REG_WTSR_SMPL_CNTL,
117 	REG_RTC_SEC,
118 	REG_RTC_MIN,
119 	REG_RTC_HOUR,
120 	REG_RTC_WEEKDAY,
121 	REG_RTC_MONTH,
122 	REG_RTC_YEAR,
123 	REG_RTC_DATE,
124 	REG_ALARM1_SEC,
125 	REG_ALARM1_MIN,
126 	REG_ALARM1_HOUR,
127 	REG_ALARM1_WEEKDAY,
128 	REG_ALARM1_MONTH,
129 	REG_ALARM1_YEAR,
130 	REG_ALARM1_DATE,
131 	REG_ALARM2_SEC,
132 	REG_ALARM2_MIN,
133 	REG_ALARM2_HOUR,
134 	REG_ALARM2_WEEKDAY,
135 	REG_ALARM2_MONTH,
136 	REG_ALARM2_YEAR,
137 	REG_ALARM2_DATE,
138 	REG_RTC_AE1,
139 	REG_RTC_END,
140 };
141 
142 /* Maps RTC registers offset to the MAX77686 register addresses */
143 static const unsigned int max77686_map[REG_RTC_END] = {
144 	[REG_RTC_CONTROLM]   = MAX77686_RTC_CONTROLM,
145 	[REG_RTC_CONTROL]    = MAX77686_RTC_CONTROL,
146 	[REG_RTC_UPDATE0]    = MAX77686_RTC_UPDATE0,
147 	[REG_WTSR_SMPL_CNTL] = MAX77686_WTSR_SMPL_CNTL,
148 	[REG_RTC_SEC]        = MAX77686_RTC_SEC,
149 	[REG_RTC_MIN]        = MAX77686_RTC_MIN,
150 	[REG_RTC_HOUR]       = MAX77686_RTC_HOUR,
151 	[REG_RTC_WEEKDAY]    = MAX77686_RTC_WEEKDAY,
152 	[REG_RTC_MONTH]      = MAX77686_RTC_MONTH,
153 	[REG_RTC_YEAR]       = MAX77686_RTC_YEAR,
154 	[REG_RTC_DATE]       = MAX77686_RTC_DATE,
155 	[REG_ALARM1_SEC]     = MAX77686_ALARM1_SEC,
156 	[REG_ALARM1_MIN]     = MAX77686_ALARM1_MIN,
157 	[REG_ALARM1_HOUR]    = MAX77686_ALARM1_HOUR,
158 	[REG_ALARM1_WEEKDAY] = MAX77686_ALARM1_WEEKDAY,
159 	[REG_ALARM1_MONTH]   = MAX77686_ALARM1_MONTH,
160 	[REG_ALARM1_YEAR]    = MAX77686_ALARM1_YEAR,
161 	[REG_ALARM1_DATE]    = MAX77686_ALARM1_DATE,
162 	[REG_ALARM2_SEC]     = MAX77686_ALARM2_SEC,
163 	[REG_ALARM2_MIN]     = MAX77686_ALARM2_MIN,
164 	[REG_ALARM2_HOUR]    = MAX77686_ALARM2_HOUR,
165 	[REG_ALARM2_WEEKDAY] = MAX77686_ALARM2_WEEKDAY,
166 	[REG_ALARM2_MONTH]   = MAX77686_ALARM2_MONTH,
167 	[REG_ALARM2_YEAR]    = MAX77686_ALARM2_YEAR,
168 	[REG_ALARM2_DATE]    = MAX77686_ALARM2_DATE,
169 	[REG_RTC_AE1]	     = REG_RTC_NONE,
170 };
171 
172 static const struct regmap_irq max77686_rtc_irqs[] = {
173 	/* RTC interrupts */
174 	REGMAP_IRQ_REG(0, 0, MAX77686_RTCINT_RTC60S_MSK),
175 	REGMAP_IRQ_REG(1, 0, MAX77686_RTCINT_RTCA1_MSK),
176 	REGMAP_IRQ_REG(2, 0, MAX77686_RTCINT_RTCA2_MSK),
177 	REGMAP_IRQ_REG(3, 0, MAX77686_RTCINT_SMPL_MSK),
178 	REGMAP_IRQ_REG(4, 0, MAX77686_RTCINT_RTC1S_MSK),
179 	REGMAP_IRQ_REG(5, 0, MAX77686_RTCINT_WTSR_MSK),
180 };
181 
182 static const struct regmap_irq_chip max77686_rtc_irq_chip = {
183 	.name		= "max77686-rtc",
184 	.status_base	= MAX77686_RTC_INT,
185 	.mask_base	= MAX77686_RTC_INTM,
186 	.num_regs	= 1,
187 	.irqs		= max77686_rtc_irqs,
188 	.num_irqs	= ARRAY_SIZE(max77686_rtc_irqs),
189 };
190 
191 static const struct max77686_rtc_driver_data max77686_drv_data = {
192 	.delay = 16000,
193 	.mask  = 0x7f,
194 	.map   = max77686_map,
195 	.alarm_enable_reg  = false,
196 	.rtc_irq_from_platform = false,
197 	.alarm_pending_status_reg = MAX77686_REG_STATUS2,
198 	.rtc_i2c_addr = MAX77686_I2C_ADDR_RTC,
199 	.rtc_irq_chip = &max77686_rtc_irq_chip,
200 };
201 
202 static const struct max77686_rtc_driver_data max77620_drv_data = {
203 	.delay = 16000,
204 	.mask  = 0x7f,
205 	.map   = max77686_map,
206 	.alarm_enable_reg  = false,
207 	.rtc_irq_from_platform = true,
208 	.alarm_pending_status_reg = MAX77686_INVALID_REG,
209 	.rtc_i2c_addr = MAX77620_I2C_ADDR_RTC,
210 	.rtc_irq_chip = &max77686_rtc_irq_chip,
211 };
212 
213 static const unsigned int max77802_map[REG_RTC_END] = {
214 	[REG_RTC_CONTROLM]   = MAX77802_RTC_CONTROLM,
215 	[REG_RTC_CONTROL]    = MAX77802_RTC_CONTROL,
216 	[REG_RTC_UPDATE0]    = MAX77802_RTC_UPDATE0,
217 	[REG_WTSR_SMPL_CNTL] = MAX77802_WTSR_SMPL_CNTL,
218 	[REG_RTC_SEC]        = MAX77802_RTC_SEC,
219 	[REG_RTC_MIN]        = MAX77802_RTC_MIN,
220 	[REG_RTC_HOUR]       = MAX77802_RTC_HOUR,
221 	[REG_RTC_WEEKDAY]    = MAX77802_RTC_WEEKDAY,
222 	[REG_RTC_MONTH]      = MAX77802_RTC_MONTH,
223 	[REG_RTC_YEAR]       = MAX77802_RTC_YEAR,
224 	[REG_RTC_DATE]       = MAX77802_RTC_DATE,
225 	[REG_ALARM1_SEC]     = MAX77802_ALARM1_SEC,
226 	[REG_ALARM1_MIN]     = MAX77802_ALARM1_MIN,
227 	[REG_ALARM1_HOUR]    = MAX77802_ALARM1_HOUR,
228 	[REG_ALARM1_WEEKDAY] = MAX77802_ALARM1_WEEKDAY,
229 	[REG_ALARM1_MONTH]   = MAX77802_ALARM1_MONTH,
230 	[REG_ALARM1_YEAR]    = MAX77802_ALARM1_YEAR,
231 	[REG_ALARM1_DATE]    = MAX77802_ALARM1_DATE,
232 	[REG_ALARM2_SEC]     = MAX77802_ALARM2_SEC,
233 	[REG_ALARM2_MIN]     = MAX77802_ALARM2_MIN,
234 	[REG_ALARM2_HOUR]    = MAX77802_ALARM2_HOUR,
235 	[REG_ALARM2_WEEKDAY] = MAX77802_ALARM2_WEEKDAY,
236 	[REG_ALARM2_MONTH]   = MAX77802_ALARM2_MONTH,
237 	[REG_ALARM2_YEAR]    = MAX77802_ALARM2_YEAR,
238 	[REG_ALARM2_DATE]    = MAX77802_ALARM2_DATE,
239 	[REG_RTC_AE1]	     = MAX77802_RTC_AE1,
240 };
241 
242 static const struct regmap_irq_chip max77802_rtc_irq_chip = {
243 	.name		= "max77802-rtc",
244 	.status_base	= MAX77802_RTC_INT,
245 	.mask_base	= MAX77802_RTC_INTM,
246 	.num_regs	= 1,
247 	.irqs		= max77686_rtc_irqs, /* same masks as 77686 */
248 	.num_irqs	= ARRAY_SIZE(max77686_rtc_irqs),
249 };
250 
251 static const struct max77686_rtc_driver_data max77802_drv_data = {
252 	.delay = 200,
253 	.mask  = 0xff,
254 	.map   = max77802_map,
255 	.alarm_enable_reg  = true,
256 	.rtc_irq_from_platform = false,
257 	.alarm_pending_status_reg = MAX77686_REG_STATUS2,
258 	.rtc_i2c_addr = MAX77686_INVALID_I2C_ADDR,
259 	.rtc_irq_chip = &max77802_rtc_irq_chip,
260 };
261 
262 static void max77686_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
263 				    struct max77686_rtc_info *info)
264 {
265 	u8 mask = info->drv_data->mask;
266 
267 	tm->tm_sec = data[RTC_SEC] & mask;
268 	tm->tm_min = data[RTC_MIN] & mask;
269 	if (info->rtc_24hr_mode) {
270 		tm->tm_hour = data[RTC_HOUR] & 0x1f;
271 	} else {
272 		tm->tm_hour = data[RTC_HOUR] & 0x0f;
273 		if (data[RTC_HOUR] & HOUR_PM_MASK)
274 			tm->tm_hour += 12;
275 	}
276 
277 	/* Only a single bit is set in data[], so fls() would be equivalent */
278 	tm->tm_wday = ffs(data[RTC_WEEKDAY] & mask) - 1;
279 	tm->tm_mday = data[RTC_DATE] & 0x1f;
280 	tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1;
281 	tm->tm_year = data[RTC_YEAR] & mask;
282 	tm->tm_yday = 0;
283 	tm->tm_isdst = 0;
284 
285 	/*
286 	 * MAX77686 uses 1 bit from sec/min/hour/etc RTC registers and the
287 	 * year values are just 0..99 so add 100 to support up to 2099.
288 	 */
289 	if (!info->drv_data->alarm_enable_reg)
290 		tm->tm_year += 100;
291 }
292 
293 static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data,
294 				   struct max77686_rtc_info *info)
295 {
296 	data[RTC_SEC] = tm->tm_sec;
297 	data[RTC_MIN] = tm->tm_min;
298 	data[RTC_HOUR] = tm->tm_hour;
299 	data[RTC_WEEKDAY] = 1 << tm->tm_wday;
300 	data[RTC_DATE] = tm->tm_mday;
301 	data[RTC_MONTH] = tm->tm_mon + 1;
302 
303 	if (info->drv_data->alarm_enable_reg) {
304 		data[RTC_YEAR] = tm->tm_year;
305 		return 0;
306 	}
307 
308 	data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
309 
310 	if (tm->tm_year < 100) {
311 		dev_err(info->dev, "RTC cannot handle the year %d.\n",
312 			1900 + tm->tm_year);
313 		return -EINVAL;
314 	}
315 
316 	return 0;
317 }
318 
319 static int max77686_rtc_update(struct max77686_rtc_info *info,
320 			       enum MAX77686_RTC_OP op)
321 {
322 	int ret;
323 	unsigned int data;
324 	unsigned long delay = info->drv_data->delay;
325 
326 	if (op == MAX77686_RTC_WRITE)
327 		data = 1 << RTC_UDR_SHIFT;
328 	else
329 		data = 1 << RTC_RBUDR_SHIFT;
330 
331 	ret = regmap_update_bits(info->rtc_regmap,
332 				 info->drv_data->map[REG_RTC_UPDATE0],
333 				 data, data);
334 	if (ret < 0)
335 		dev_err(info->dev, "Fail to write update reg(ret=%d, data=0x%x)\n",
336 			ret, data);
337 	else {
338 		/* Minimum delay required before RTC update. */
339 		usleep_range(delay, delay * 2);
340 	}
341 
342 	return ret;
343 }
344 
345 static int max77686_rtc_read_time(struct device *dev, struct rtc_time *tm)
346 {
347 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
348 	u8 data[RTC_NR_TIME];
349 	int ret;
350 
351 	mutex_lock(&info->lock);
352 
353 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
354 	if (ret < 0)
355 		goto out;
356 
357 	ret = regmap_bulk_read(info->rtc_regmap,
358 			       info->drv_data->map[REG_RTC_SEC],
359 			       data, ARRAY_SIZE(data));
360 	if (ret < 0) {
361 		dev_err(info->dev, "Fail to read time reg(%d)\n", ret);
362 		goto out;
363 	}
364 
365 	max77686_rtc_data_to_tm(data, tm, info);
366 
367 	ret = rtc_valid_tm(tm);
368 
369 out:
370 	mutex_unlock(&info->lock);
371 	return ret;
372 }
373 
374 static int max77686_rtc_set_time(struct device *dev, struct rtc_time *tm)
375 {
376 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
377 	u8 data[RTC_NR_TIME];
378 	int ret;
379 
380 	ret = max77686_rtc_tm_to_data(tm, data, info);
381 	if (ret < 0)
382 		return ret;
383 
384 	mutex_lock(&info->lock);
385 
386 	ret = regmap_bulk_write(info->rtc_regmap,
387 				info->drv_data->map[REG_RTC_SEC],
388 				data, ARRAY_SIZE(data));
389 	if (ret < 0) {
390 		dev_err(info->dev, "Fail to write time reg(%d)\n", ret);
391 		goto out;
392 	}
393 
394 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
395 
396 out:
397 	mutex_unlock(&info->lock);
398 	return ret;
399 }
400 
401 static int max77686_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
402 {
403 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
404 	u8 data[RTC_NR_TIME];
405 	unsigned int val;
406 	const unsigned int *map = info->drv_data->map;
407 	int i, ret;
408 
409 	mutex_lock(&info->lock);
410 
411 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
412 	if (ret < 0)
413 		goto out;
414 
415 	ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
416 			       data, ARRAY_SIZE(data));
417 	if (ret < 0) {
418 		dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
419 		goto out;
420 	}
421 
422 	max77686_rtc_data_to_tm(data, &alrm->time, info);
423 
424 	alrm->enabled = 0;
425 
426 	if (info->drv_data->alarm_enable_reg) {
427 		if (map[REG_RTC_AE1] == REG_RTC_NONE) {
428 			ret = -EINVAL;
429 			dev_err(info->dev,
430 				"alarm enable register not set(%d)\n", ret);
431 			goto out;
432 		}
433 
434 		ret = regmap_read(info->rtc_regmap, map[REG_RTC_AE1], &val);
435 		if (ret < 0) {
436 			dev_err(info->dev,
437 				"fail to read alarm enable(%d)\n", ret);
438 			goto out;
439 		}
440 
441 		if (val)
442 			alrm->enabled = 1;
443 	} else {
444 		for (i = 0; i < ARRAY_SIZE(data); i++) {
445 			if (data[i] & ALARM_ENABLE_MASK) {
446 				alrm->enabled = 1;
447 				break;
448 			}
449 		}
450 	}
451 
452 	alrm->pending = 0;
453 
454 	if (info->drv_data->alarm_pending_status_reg == MAX77686_INVALID_REG)
455 		goto out;
456 
457 	ret = regmap_read(info->regmap,
458 			  info->drv_data->alarm_pending_status_reg, &val);
459 	if (ret < 0) {
460 		dev_err(info->dev,
461 			"Fail to read alarm pending status reg(%d)\n", ret);
462 		goto out;
463 	}
464 
465 	if (val & (1 << 4)) /* RTCA1 */
466 		alrm->pending = 1;
467 
468 out:
469 	mutex_unlock(&info->lock);
470 	return ret;
471 }
472 
473 static int max77686_rtc_stop_alarm(struct max77686_rtc_info *info)
474 {
475 	u8 data[RTC_NR_TIME];
476 	int ret, i;
477 	struct rtc_time tm;
478 	const unsigned int *map = info->drv_data->map;
479 
480 	if (!mutex_is_locked(&info->lock))
481 		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
482 
483 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
484 	if (ret < 0)
485 		goto out;
486 
487 	if (info->drv_data->alarm_enable_reg) {
488 		if (map[REG_RTC_AE1] == REG_RTC_NONE) {
489 			ret = -EINVAL;
490 			dev_err(info->dev,
491 				"alarm enable register not set(%d)\n", ret);
492 			goto out;
493 		}
494 
495 		ret = regmap_write(info->rtc_regmap, map[REG_RTC_AE1], 0);
496 	} else {
497 		ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
498 				       data, ARRAY_SIZE(data));
499 		if (ret < 0) {
500 			dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
501 			goto out;
502 		}
503 
504 		max77686_rtc_data_to_tm(data, &tm, info);
505 
506 		for (i = 0; i < ARRAY_SIZE(data); i++)
507 			data[i] &= ~ALARM_ENABLE_MASK;
508 
509 		ret = regmap_bulk_write(info->rtc_regmap, map[REG_ALARM1_SEC],
510 					data, ARRAY_SIZE(data));
511 	}
512 
513 	if (ret < 0) {
514 		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
515 		goto out;
516 	}
517 
518 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
519 out:
520 	return ret;
521 }
522 
523 static int max77686_rtc_start_alarm(struct max77686_rtc_info *info)
524 {
525 	u8 data[RTC_NR_TIME];
526 	int ret;
527 	struct rtc_time tm;
528 	const unsigned int *map = info->drv_data->map;
529 
530 	if (!mutex_is_locked(&info->lock))
531 		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
532 
533 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
534 	if (ret < 0)
535 		goto out;
536 
537 	if (info->drv_data->alarm_enable_reg) {
538 		ret = regmap_write(info->rtc_regmap, map[REG_RTC_AE1],
539 				   MAX77802_ALARM_ENABLE_VALUE);
540 	} else {
541 		ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
542 				       data, ARRAY_SIZE(data));
543 		if (ret < 0) {
544 			dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
545 			goto out;
546 		}
547 
548 		max77686_rtc_data_to_tm(data, &tm, info);
549 
550 		data[RTC_SEC] |= (1 << ALARM_ENABLE_SHIFT);
551 		data[RTC_MIN] |= (1 << ALARM_ENABLE_SHIFT);
552 		data[RTC_HOUR] |= (1 << ALARM_ENABLE_SHIFT);
553 		data[RTC_WEEKDAY] &= ~ALARM_ENABLE_MASK;
554 		if (data[RTC_MONTH] & 0xf)
555 			data[RTC_MONTH] |= (1 << ALARM_ENABLE_SHIFT);
556 		if (data[RTC_YEAR] & info->drv_data->mask)
557 			data[RTC_YEAR] |= (1 << ALARM_ENABLE_SHIFT);
558 		if (data[RTC_DATE] & 0x1f)
559 			data[RTC_DATE] |= (1 << ALARM_ENABLE_SHIFT);
560 
561 		ret = regmap_bulk_write(info->rtc_regmap, map[REG_ALARM1_SEC],
562 					data, ARRAY_SIZE(data));
563 	}
564 
565 	if (ret < 0) {
566 		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
567 		goto out;
568 	}
569 
570 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
571 out:
572 	return ret;
573 }
574 
575 static int max77686_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
576 {
577 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
578 	u8 data[RTC_NR_TIME];
579 	int ret;
580 
581 	ret = max77686_rtc_tm_to_data(&alrm->time, data, info);
582 	if (ret < 0)
583 		return ret;
584 
585 	mutex_lock(&info->lock);
586 
587 	ret = max77686_rtc_stop_alarm(info);
588 	if (ret < 0)
589 		goto out;
590 
591 	ret = regmap_bulk_write(info->rtc_regmap,
592 				info->drv_data->map[REG_ALARM1_SEC],
593 				data, ARRAY_SIZE(data));
594 
595 	if (ret < 0) {
596 		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
597 		goto out;
598 	}
599 
600 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
601 	if (ret < 0)
602 		goto out;
603 
604 	if (alrm->enabled)
605 		ret = max77686_rtc_start_alarm(info);
606 out:
607 	mutex_unlock(&info->lock);
608 	return ret;
609 }
610 
611 static int max77686_rtc_alarm_irq_enable(struct device *dev,
612 					 unsigned int enabled)
613 {
614 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
615 	int ret;
616 
617 	mutex_lock(&info->lock);
618 	if (enabled)
619 		ret = max77686_rtc_start_alarm(info);
620 	else
621 		ret = max77686_rtc_stop_alarm(info);
622 	mutex_unlock(&info->lock);
623 
624 	return ret;
625 }
626 
627 static irqreturn_t max77686_rtc_alarm_irq(int irq, void *data)
628 {
629 	struct max77686_rtc_info *info = data;
630 
631 	dev_dbg(info->dev, "RTC alarm IRQ: %d\n", irq);
632 
633 	rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
634 
635 	return IRQ_HANDLED;
636 }
637 
638 static const struct rtc_class_ops max77686_rtc_ops = {
639 	.read_time = max77686_rtc_read_time,
640 	.set_time = max77686_rtc_set_time,
641 	.read_alarm = max77686_rtc_read_alarm,
642 	.set_alarm = max77686_rtc_set_alarm,
643 	.alarm_irq_enable = max77686_rtc_alarm_irq_enable,
644 };
645 
646 static int max77686_rtc_init_reg(struct max77686_rtc_info *info)
647 {
648 	u8 data[2];
649 	int ret;
650 
651 	/* Set RTC control register : Binary mode, 24hour mdoe */
652 	data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
653 	data[1] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
654 
655 	info->rtc_24hr_mode = 1;
656 
657 	ret = regmap_bulk_write(info->rtc_regmap,
658 				info->drv_data->map[REG_RTC_CONTROLM],
659 				data, ARRAY_SIZE(data));
660 	if (ret < 0) {
661 		dev_err(info->dev, "Fail to write controlm reg(%d)\n", ret);
662 		return ret;
663 	}
664 
665 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
666 	return ret;
667 }
668 
669 static const struct regmap_config max77686_rtc_regmap_config = {
670 	.reg_bits = 8,
671 	.val_bits = 8,
672 };
673 
674 static int max77686_init_rtc_regmap(struct max77686_rtc_info *info)
675 {
676 	struct device *parent = info->dev->parent;
677 	struct i2c_client *parent_i2c = to_i2c_client(parent);
678 	int ret;
679 
680 	if (info->drv_data->rtc_irq_from_platform) {
681 		struct platform_device *pdev = to_platform_device(info->dev);
682 
683 		info->rtc_irq = platform_get_irq(pdev, 0);
684 		if (info->rtc_irq < 0) {
685 			dev_err(info->dev, "Failed to get rtc interrupts: %d\n",
686 				info->rtc_irq);
687 			return info->rtc_irq;
688 		}
689 	} else {
690 		info->rtc_irq =  parent_i2c->irq;
691 	}
692 
693 	info->regmap = dev_get_regmap(parent, NULL);
694 	if (!info->regmap) {
695 		dev_err(info->dev, "Failed to get rtc regmap\n");
696 		return -ENODEV;
697 	}
698 
699 	if (info->drv_data->rtc_i2c_addr == MAX77686_INVALID_I2C_ADDR) {
700 		info->rtc_regmap = info->regmap;
701 		goto add_rtc_irq;
702 	}
703 
704 	info->rtc = i2c_new_dummy(parent_i2c->adapter,
705 				  info->drv_data->rtc_i2c_addr);
706 	if (!info->rtc) {
707 		dev_err(info->dev, "Failed to allocate I2C device for RTC\n");
708 		return -ENODEV;
709 	}
710 
711 	info->rtc_regmap = devm_regmap_init_i2c(info->rtc,
712 						&max77686_rtc_regmap_config);
713 	if (IS_ERR(info->rtc_regmap)) {
714 		ret = PTR_ERR(info->rtc_regmap);
715 		dev_err(info->dev, "Failed to allocate RTC regmap: %d\n", ret);
716 		goto err_unregister_i2c;
717 	}
718 
719 add_rtc_irq:
720 	ret = regmap_add_irq_chip(info->rtc_regmap, info->rtc_irq,
721 				  IRQF_TRIGGER_FALLING | IRQF_ONESHOT |
722 				  IRQF_SHARED, 0, info->drv_data->rtc_irq_chip,
723 				  &info->rtc_irq_data);
724 	if (ret < 0) {
725 		dev_err(info->dev, "Failed to add RTC irq chip: %d\n", ret);
726 		goto err_unregister_i2c;
727 	}
728 
729 	return 0;
730 
731 err_unregister_i2c:
732 	if (info->rtc)
733 		i2c_unregister_device(info->rtc);
734 	return ret;
735 }
736 
737 static int max77686_rtc_probe(struct platform_device *pdev)
738 {
739 	struct max77686_rtc_info *info;
740 	const struct platform_device_id *id = platform_get_device_id(pdev);
741 	int ret;
742 
743 	info = devm_kzalloc(&pdev->dev, sizeof(struct max77686_rtc_info),
744 			    GFP_KERNEL);
745 	if (!info)
746 		return -ENOMEM;
747 
748 	mutex_init(&info->lock);
749 	info->dev = &pdev->dev;
750 	info->drv_data = (const struct max77686_rtc_driver_data *)
751 		id->driver_data;
752 
753 	ret = max77686_init_rtc_regmap(info);
754 	if (ret < 0)
755 		return ret;
756 
757 	platform_set_drvdata(pdev, info);
758 
759 	ret = max77686_rtc_init_reg(info);
760 	if (ret < 0) {
761 		dev_err(&pdev->dev, "Failed to initialize RTC reg:%d\n", ret);
762 		goto err_rtc;
763 	}
764 
765 	device_init_wakeup(&pdev->dev, 1);
766 
767 	info->rtc_dev = devm_rtc_device_register(&pdev->dev, id->name,
768 					&max77686_rtc_ops, THIS_MODULE);
769 
770 	if (IS_ERR(info->rtc_dev)) {
771 		ret = PTR_ERR(info->rtc_dev);
772 		dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
773 		if (ret == 0)
774 			ret = -EINVAL;
775 		goto err_rtc;
776 	}
777 
778 	info->virq = regmap_irq_get_virq(info->rtc_irq_data,
779 					 MAX77686_RTCIRQ_RTCA1);
780 	if (info->virq <= 0) {
781 		ret = -ENXIO;
782 		goto err_rtc;
783 	}
784 
785 	ret = request_threaded_irq(info->virq, NULL, max77686_rtc_alarm_irq, 0,
786 				   "rtc-alarm1", info);
787 	if (ret < 0) {
788 		dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
789 			info->virq, ret);
790 		goto err_rtc;
791 	}
792 
793 	return 0;
794 
795 err_rtc:
796 	regmap_del_irq_chip(info->rtc_irq, info->rtc_irq_data);
797 	if (info->rtc)
798 		i2c_unregister_device(info->rtc);
799 
800 	return ret;
801 }
802 
803 static int max77686_rtc_remove(struct platform_device *pdev)
804 {
805 	struct max77686_rtc_info *info = platform_get_drvdata(pdev);
806 
807 	free_irq(info->virq, info);
808 	regmap_del_irq_chip(info->rtc_irq, info->rtc_irq_data);
809 	if (info->rtc)
810 		i2c_unregister_device(info->rtc);
811 
812 	return 0;
813 }
814 
815 #ifdef CONFIG_PM_SLEEP
816 static int max77686_rtc_suspend(struct device *dev)
817 {
818 	if (device_may_wakeup(dev)) {
819 		struct max77686_rtc_info *info = dev_get_drvdata(dev);
820 
821 		return enable_irq_wake(info->virq);
822 	}
823 
824 	return 0;
825 }
826 
827 static int max77686_rtc_resume(struct device *dev)
828 {
829 	if (device_may_wakeup(dev)) {
830 		struct max77686_rtc_info *info = dev_get_drvdata(dev);
831 
832 		return disable_irq_wake(info->virq);
833 	}
834 
835 	return 0;
836 }
837 #endif
838 
839 static SIMPLE_DEV_PM_OPS(max77686_rtc_pm_ops,
840 			 max77686_rtc_suspend, max77686_rtc_resume);
841 
842 static const struct platform_device_id rtc_id[] = {
843 	{ "max77686-rtc", .driver_data = (kernel_ulong_t)&max77686_drv_data, },
844 	{ "max77802-rtc", .driver_data = (kernel_ulong_t)&max77802_drv_data, },
845 	{ "max77620-rtc", .driver_data = (kernel_ulong_t)&max77620_drv_data, },
846 	{},
847 };
848 MODULE_DEVICE_TABLE(platform, rtc_id);
849 
850 static struct platform_driver max77686_rtc_driver = {
851 	.driver		= {
852 		.name	= "max77686-rtc",
853 		.pm	= &max77686_rtc_pm_ops,
854 	},
855 	.probe		= max77686_rtc_probe,
856 	.remove		= max77686_rtc_remove,
857 	.id_table	= rtc_id,
858 };
859 
860 module_platform_driver(max77686_rtc_driver);
861 
862 MODULE_DESCRIPTION("Maxim MAX77686 RTC driver");
863 MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
864 MODULE_LICENSE("GPL");
865