xref: /openbmc/linux/drivers/rtc/rtc-max77686.c (revision f7af616c)
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // RTC driver for Maxim MAX77686 and MAX77802
4 //
5 // Copyright (C) 2012 Samsung Electronics Co.Ltd
6 //
7 //  based on rtc-max8997.c
8 
9 #include <linux/i2c.h>
10 #include <linux/slab.h>
11 #include <linux/rtc.h>
12 #include <linux/delay.h>
13 #include <linux/mutex.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/mfd/max77686-private.h>
17 #include <linux/irqdomain.h>
18 #include <linux/regmap.h>
19 
20 #define MAX77686_I2C_ADDR_RTC		(0x0C >> 1)
21 #define MAX77620_I2C_ADDR_RTC		0x68
22 #define MAX77686_INVALID_I2C_ADDR	(-1)
23 
24 /* Define non existing register */
25 #define MAX77686_INVALID_REG		(-1)
26 
27 /* RTC Control Register */
28 #define BCD_EN_SHIFT			0
29 #define BCD_EN_MASK			BIT(BCD_EN_SHIFT)
30 #define MODEL24_SHIFT			1
31 #define MODEL24_MASK			BIT(MODEL24_SHIFT)
32 /* RTC Update Register1 */
33 #define RTC_UDR_SHIFT			0
34 #define RTC_UDR_MASK			BIT(RTC_UDR_SHIFT)
35 #define RTC_RBUDR_SHIFT			4
36 #define RTC_RBUDR_MASK			BIT(RTC_RBUDR_SHIFT)
37 /* RTC Hour register */
38 #define HOUR_PM_SHIFT			6
39 #define HOUR_PM_MASK			BIT(HOUR_PM_SHIFT)
40 /* RTC Alarm Enable */
41 #define ALARM_ENABLE_SHIFT		7
42 #define ALARM_ENABLE_MASK		BIT(ALARM_ENABLE_SHIFT)
43 
44 #define REG_RTC_NONE			0xdeadbeef
45 
46 /*
47  * MAX77802 has separate register (RTCAE1) for alarm enable instead
48  * using 1 bit from registers RTC{SEC,MIN,HOUR,DAY,MONTH,YEAR,DATE}
49  * as in done in MAX77686.
50  */
51 #define MAX77802_ALARM_ENABLE_VALUE	0x77
52 
53 enum {
54 	RTC_SEC = 0,
55 	RTC_MIN,
56 	RTC_HOUR,
57 	RTC_WEEKDAY,
58 	RTC_MONTH,
59 	RTC_YEAR,
60 	RTC_DATE,
61 	RTC_NR_TIME
62 };
63 
64 struct max77686_rtc_driver_data {
65 	/* Minimum usecs needed for a RTC update */
66 	unsigned long		delay;
67 	/* Mask used to read RTC registers value */
68 	u8			mask;
69 	/* Registers offset to I2C addresses map */
70 	const unsigned int	*map;
71 	/* Has a separate alarm enable register? */
72 	bool			alarm_enable_reg;
73 	/* I2C address for RTC block */
74 	int			rtc_i2c_addr;
75 	/* RTC interrupt via platform resource */
76 	bool			rtc_irq_from_platform;
77 	/* Pending alarm status register */
78 	int			alarm_pending_status_reg;
79 	/* RTC IRQ CHIP for regmap */
80 	const struct regmap_irq_chip *rtc_irq_chip;
81 	/* regmap configuration for the chip */
82 	const struct regmap_config *regmap_config;
83 };
84 
85 struct max77686_rtc_info {
86 	struct device		*dev;
87 	struct i2c_client	*rtc;
88 	struct rtc_device	*rtc_dev;
89 	struct mutex		lock;
90 
91 	struct regmap		*regmap;
92 	struct regmap		*rtc_regmap;
93 
94 	const struct max77686_rtc_driver_data *drv_data;
95 	struct regmap_irq_chip_data *rtc_irq_data;
96 
97 	int rtc_irq;
98 	int virq;
99 	int rtc_24hr_mode;
100 };
101 
102 enum MAX77686_RTC_OP {
103 	MAX77686_RTC_WRITE,
104 	MAX77686_RTC_READ,
105 };
106 
107 /* These are not registers but just offsets that are mapped to addresses */
108 enum max77686_rtc_reg_offset {
109 	REG_RTC_CONTROLM = 0,
110 	REG_RTC_CONTROL,
111 	REG_RTC_UPDATE0,
112 	REG_WTSR_SMPL_CNTL,
113 	REG_RTC_SEC,
114 	REG_RTC_MIN,
115 	REG_RTC_HOUR,
116 	REG_RTC_WEEKDAY,
117 	REG_RTC_MONTH,
118 	REG_RTC_YEAR,
119 	REG_RTC_DATE,
120 	REG_ALARM1_SEC,
121 	REG_ALARM1_MIN,
122 	REG_ALARM1_HOUR,
123 	REG_ALARM1_WEEKDAY,
124 	REG_ALARM1_MONTH,
125 	REG_ALARM1_YEAR,
126 	REG_ALARM1_DATE,
127 	REG_ALARM2_SEC,
128 	REG_ALARM2_MIN,
129 	REG_ALARM2_HOUR,
130 	REG_ALARM2_WEEKDAY,
131 	REG_ALARM2_MONTH,
132 	REG_ALARM2_YEAR,
133 	REG_ALARM2_DATE,
134 	REG_RTC_AE1,
135 	REG_RTC_END,
136 };
137 
138 /* Maps RTC registers offset to the MAX77686 register addresses */
139 static const unsigned int max77686_map[REG_RTC_END] = {
140 	[REG_RTC_CONTROLM]   = MAX77686_RTC_CONTROLM,
141 	[REG_RTC_CONTROL]    = MAX77686_RTC_CONTROL,
142 	[REG_RTC_UPDATE0]    = MAX77686_RTC_UPDATE0,
143 	[REG_WTSR_SMPL_CNTL] = MAX77686_WTSR_SMPL_CNTL,
144 	[REG_RTC_SEC]        = MAX77686_RTC_SEC,
145 	[REG_RTC_MIN]        = MAX77686_RTC_MIN,
146 	[REG_RTC_HOUR]       = MAX77686_RTC_HOUR,
147 	[REG_RTC_WEEKDAY]    = MAX77686_RTC_WEEKDAY,
148 	[REG_RTC_MONTH]      = MAX77686_RTC_MONTH,
149 	[REG_RTC_YEAR]       = MAX77686_RTC_YEAR,
150 	[REG_RTC_DATE]       = MAX77686_RTC_DATE,
151 	[REG_ALARM1_SEC]     = MAX77686_ALARM1_SEC,
152 	[REG_ALARM1_MIN]     = MAX77686_ALARM1_MIN,
153 	[REG_ALARM1_HOUR]    = MAX77686_ALARM1_HOUR,
154 	[REG_ALARM1_WEEKDAY] = MAX77686_ALARM1_WEEKDAY,
155 	[REG_ALARM1_MONTH]   = MAX77686_ALARM1_MONTH,
156 	[REG_ALARM1_YEAR]    = MAX77686_ALARM1_YEAR,
157 	[REG_ALARM1_DATE]    = MAX77686_ALARM1_DATE,
158 	[REG_ALARM2_SEC]     = MAX77686_ALARM2_SEC,
159 	[REG_ALARM2_MIN]     = MAX77686_ALARM2_MIN,
160 	[REG_ALARM2_HOUR]    = MAX77686_ALARM2_HOUR,
161 	[REG_ALARM2_WEEKDAY] = MAX77686_ALARM2_WEEKDAY,
162 	[REG_ALARM2_MONTH]   = MAX77686_ALARM2_MONTH,
163 	[REG_ALARM2_YEAR]    = MAX77686_ALARM2_YEAR,
164 	[REG_ALARM2_DATE]    = MAX77686_ALARM2_DATE,
165 	[REG_RTC_AE1]	     = REG_RTC_NONE,
166 };
167 
168 static const struct regmap_irq max77686_rtc_irqs[] = {
169 	/* RTC interrupts */
170 	REGMAP_IRQ_REG(0, 0, MAX77686_RTCINT_RTC60S_MSK),
171 	REGMAP_IRQ_REG(1, 0, MAX77686_RTCINT_RTCA1_MSK),
172 	REGMAP_IRQ_REG(2, 0, MAX77686_RTCINT_RTCA2_MSK),
173 	REGMAP_IRQ_REG(3, 0, MAX77686_RTCINT_SMPL_MSK),
174 	REGMAP_IRQ_REG(4, 0, MAX77686_RTCINT_RTC1S_MSK),
175 	REGMAP_IRQ_REG(5, 0, MAX77686_RTCINT_WTSR_MSK),
176 };
177 
178 static const struct regmap_irq_chip max77686_rtc_irq_chip = {
179 	.name		= "max77686-rtc",
180 	.status_base	= MAX77686_RTC_INT,
181 	.mask_base	= MAX77686_RTC_INTM,
182 	.num_regs	= 1,
183 	.irqs		= max77686_rtc_irqs,
184 	.num_irqs	= ARRAY_SIZE(max77686_rtc_irqs),
185 };
186 
187 static const struct regmap_config max77686_rtc_regmap_config = {
188 	.reg_bits = 8,
189 	.val_bits = 8,
190 };
191 
192 static const struct max77686_rtc_driver_data max77686_drv_data = {
193 	.delay = 16000,
194 	.mask  = 0x7f,
195 	.map   = max77686_map,
196 	.alarm_enable_reg  = false,
197 	.rtc_irq_from_platform = false,
198 	.alarm_pending_status_reg = MAX77686_REG_STATUS2,
199 	.rtc_i2c_addr = MAX77686_I2C_ADDR_RTC,
200 	.rtc_irq_chip = &max77686_rtc_irq_chip,
201 	.regmap_config = &max77686_rtc_regmap_config,
202 };
203 
204 static const struct regmap_config max77620_rtc_regmap_config = {
205 	.reg_bits = 8,
206 	.val_bits = 8,
207 	.use_single_write = true,
208 };
209 
210 static const struct max77686_rtc_driver_data max77620_drv_data = {
211 	.delay = 16000,
212 	.mask  = 0x7f,
213 	.map   = max77686_map,
214 	.alarm_enable_reg  = false,
215 	.rtc_irq_from_platform = true,
216 	.alarm_pending_status_reg = MAX77686_INVALID_REG,
217 	.rtc_i2c_addr = MAX77620_I2C_ADDR_RTC,
218 	.rtc_irq_chip = &max77686_rtc_irq_chip,
219 	.regmap_config = &max77620_rtc_regmap_config,
220 };
221 
222 static const unsigned int max77802_map[REG_RTC_END] = {
223 	[REG_RTC_CONTROLM]   = MAX77802_RTC_CONTROLM,
224 	[REG_RTC_CONTROL]    = MAX77802_RTC_CONTROL,
225 	[REG_RTC_UPDATE0]    = MAX77802_RTC_UPDATE0,
226 	[REG_WTSR_SMPL_CNTL] = MAX77802_WTSR_SMPL_CNTL,
227 	[REG_RTC_SEC]        = MAX77802_RTC_SEC,
228 	[REG_RTC_MIN]        = MAX77802_RTC_MIN,
229 	[REG_RTC_HOUR]       = MAX77802_RTC_HOUR,
230 	[REG_RTC_WEEKDAY]    = MAX77802_RTC_WEEKDAY,
231 	[REG_RTC_MONTH]      = MAX77802_RTC_MONTH,
232 	[REG_RTC_YEAR]       = MAX77802_RTC_YEAR,
233 	[REG_RTC_DATE]       = MAX77802_RTC_DATE,
234 	[REG_ALARM1_SEC]     = MAX77802_ALARM1_SEC,
235 	[REG_ALARM1_MIN]     = MAX77802_ALARM1_MIN,
236 	[REG_ALARM1_HOUR]    = MAX77802_ALARM1_HOUR,
237 	[REG_ALARM1_WEEKDAY] = MAX77802_ALARM1_WEEKDAY,
238 	[REG_ALARM1_MONTH]   = MAX77802_ALARM1_MONTH,
239 	[REG_ALARM1_YEAR]    = MAX77802_ALARM1_YEAR,
240 	[REG_ALARM1_DATE]    = MAX77802_ALARM1_DATE,
241 	[REG_ALARM2_SEC]     = MAX77802_ALARM2_SEC,
242 	[REG_ALARM2_MIN]     = MAX77802_ALARM2_MIN,
243 	[REG_ALARM2_HOUR]    = MAX77802_ALARM2_HOUR,
244 	[REG_ALARM2_WEEKDAY] = MAX77802_ALARM2_WEEKDAY,
245 	[REG_ALARM2_MONTH]   = MAX77802_ALARM2_MONTH,
246 	[REG_ALARM2_YEAR]    = MAX77802_ALARM2_YEAR,
247 	[REG_ALARM2_DATE]    = MAX77802_ALARM2_DATE,
248 	[REG_RTC_AE1]	     = MAX77802_RTC_AE1,
249 };
250 
251 static const struct regmap_irq_chip max77802_rtc_irq_chip = {
252 	.name		= "max77802-rtc",
253 	.status_base	= MAX77802_RTC_INT,
254 	.mask_base	= MAX77802_RTC_INTM,
255 	.num_regs	= 1,
256 	.irqs		= max77686_rtc_irqs, /* same masks as 77686 */
257 	.num_irqs	= ARRAY_SIZE(max77686_rtc_irqs),
258 };
259 
260 static const struct max77686_rtc_driver_data max77802_drv_data = {
261 	.delay = 200,
262 	.mask  = 0xff,
263 	.map   = max77802_map,
264 	.alarm_enable_reg  = true,
265 	.rtc_irq_from_platform = false,
266 	.alarm_pending_status_reg = MAX77686_REG_STATUS2,
267 	.rtc_i2c_addr = MAX77686_INVALID_I2C_ADDR,
268 	.rtc_irq_chip = &max77802_rtc_irq_chip,
269 };
270 
271 static void max77686_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
272 				    struct max77686_rtc_info *info)
273 {
274 	u8 mask = info->drv_data->mask;
275 
276 	tm->tm_sec = data[RTC_SEC] & mask;
277 	tm->tm_min = data[RTC_MIN] & mask;
278 	if (info->rtc_24hr_mode) {
279 		tm->tm_hour = data[RTC_HOUR] & 0x1f;
280 	} else {
281 		tm->tm_hour = data[RTC_HOUR] & 0x0f;
282 		if (data[RTC_HOUR] & HOUR_PM_MASK)
283 			tm->tm_hour += 12;
284 	}
285 
286 	/* Only a single bit is set in data[], so fls() would be equivalent */
287 	tm->tm_wday = ffs(data[RTC_WEEKDAY] & mask) - 1;
288 	tm->tm_mday = data[RTC_DATE] & 0x1f;
289 	tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1;
290 	tm->tm_year = data[RTC_YEAR] & mask;
291 	tm->tm_yday = 0;
292 	tm->tm_isdst = 0;
293 
294 	/*
295 	 * MAX77686 uses 1 bit from sec/min/hour/etc RTC registers and the
296 	 * year values are just 0..99 so add 100 to support up to 2099.
297 	 */
298 	if (!info->drv_data->alarm_enable_reg)
299 		tm->tm_year += 100;
300 }
301 
302 static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data,
303 				   struct max77686_rtc_info *info)
304 {
305 	data[RTC_SEC] = tm->tm_sec;
306 	data[RTC_MIN] = tm->tm_min;
307 	data[RTC_HOUR] = tm->tm_hour;
308 	data[RTC_WEEKDAY] = 1 << tm->tm_wday;
309 	data[RTC_DATE] = tm->tm_mday;
310 	data[RTC_MONTH] = tm->tm_mon + 1;
311 
312 	if (info->drv_data->alarm_enable_reg) {
313 		data[RTC_YEAR] = tm->tm_year;
314 		return 0;
315 	}
316 
317 	data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
318 
319 	if (tm->tm_year < 100) {
320 		dev_err(info->dev, "RTC cannot handle the year %d.\n",
321 			1900 + tm->tm_year);
322 		return -EINVAL;
323 	}
324 
325 	return 0;
326 }
327 
328 static int max77686_rtc_update(struct max77686_rtc_info *info,
329 			       enum MAX77686_RTC_OP op)
330 {
331 	int ret;
332 	unsigned int data;
333 	unsigned long delay = info->drv_data->delay;
334 
335 	if (op == MAX77686_RTC_WRITE)
336 		data = 1 << RTC_UDR_SHIFT;
337 	else
338 		data = 1 << RTC_RBUDR_SHIFT;
339 
340 	ret = regmap_update_bits(info->rtc_regmap,
341 				 info->drv_data->map[REG_RTC_UPDATE0],
342 				 data, data);
343 	if (ret < 0)
344 		dev_err(info->dev, "Fail to write update reg(ret=%d, data=0x%x)\n",
345 			ret, data);
346 	else {
347 		/* Minimum delay required before RTC update. */
348 		usleep_range(delay, delay * 2);
349 	}
350 
351 	return ret;
352 }
353 
354 static int max77686_rtc_read_time(struct device *dev, struct rtc_time *tm)
355 {
356 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
357 	u8 data[RTC_NR_TIME];
358 	int ret;
359 
360 	mutex_lock(&info->lock);
361 
362 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
363 	if (ret < 0)
364 		goto out;
365 
366 	ret = regmap_bulk_read(info->rtc_regmap,
367 			       info->drv_data->map[REG_RTC_SEC],
368 			       data, ARRAY_SIZE(data));
369 	if (ret < 0) {
370 		dev_err(info->dev, "Fail to read time reg(%d)\n", ret);
371 		goto out;
372 	}
373 
374 	max77686_rtc_data_to_tm(data, tm, info);
375 
376 out:
377 	mutex_unlock(&info->lock);
378 	return ret;
379 }
380 
381 static int max77686_rtc_set_time(struct device *dev, struct rtc_time *tm)
382 {
383 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
384 	u8 data[RTC_NR_TIME];
385 	int ret;
386 
387 	ret = max77686_rtc_tm_to_data(tm, data, info);
388 	if (ret < 0)
389 		return ret;
390 
391 	mutex_lock(&info->lock);
392 
393 	ret = regmap_bulk_write(info->rtc_regmap,
394 				info->drv_data->map[REG_RTC_SEC],
395 				data, ARRAY_SIZE(data));
396 	if (ret < 0) {
397 		dev_err(info->dev, "Fail to write time reg(%d)\n", ret);
398 		goto out;
399 	}
400 
401 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
402 
403 out:
404 	mutex_unlock(&info->lock);
405 	return ret;
406 }
407 
408 static int max77686_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
409 {
410 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
411 	u8 data[RTC_NR_TIME];
412 	unsigned int val;
413 	const unsigned int *map = info->drv_data->map;
414 	int i, ret;
415 
416 	mutex_lock(&info->lock);
417 
418 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
419 	if (ret < 0)
420 		goto out;
421 
422 	ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
423 			       data, ARRAY_SIZE(data));
424 	if (ret < 0) {
425 		dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
426 		goto out;
427 	}
428 
429 	max77686_rtc_data_to_tm(data, &alrm->time, info);
430 
431 	alrm->enabled = 0;
432 
433 	if (info->drv_data->alarm_enable_reg) {
434 		if (map[REG_RTC_AE1] == REG_RTC_NONE) {
435 			ret = -EINVAL;
436 			dev_err(info->dev,
437 				"alarm enable register not set(%d)\n", ret);
438 			goto out;
439 		}
440 
441 		ret = regmap_read(info->rtc_regmap, map[REG_RTC_AE1], &val);
442 		if (ret < 0) {
443 			dev_err(info->dev,
444 				"fail to read alarm enable(%d)\n", ret);
445 			goto out;
446 		}
447 
448 		if (val)
449 			alrm->enabled = 1;
450 	} else {
451 		for (i = 0; i < ARRAY_SIZE(data); i++) {
452 			if (data[i] & ALARM_ENABLE_MASK) {
453 				alrm->enabled = 1;
454 				break;
455 			}
456 		}
457 	}
458 
459 	alrm->pending = 0;
460 
461 	if (info->drv_data->alarm_pending_status_reg == MAX77686_INVALID_REG)
462 		goto out;
463 
464 	ret = regmap_read(info->regmap,
465 			  info->drv_data->alarm_pending_status_reg, &val);
466 	if (ret < 0) {
467 		dev_err(info->dev,
468 			"Fail to read alarm pending status reg(%d)\n", ret);
469 		goto out;
470 	}
471 
472 	if (val & (1 << 4)) /* RTCA1 */
473 		alrm->pending = 1;
474 
475 out:
476 	mutex_unlock(&info->lock);
477 	return ret;
478 }
479 
480 static int max77686_rtc_stop_alarm(struct max77686_rtc_info *info)
481 {
482 	u8 data[RTC_NR_TIME];
483 	int ret, i;
484 	struct rtc_time tm;
485 	const unsigned int *map = info->drv_data->map;
486 
487 	if (!mutex_is_locked(&info->lock))
488 		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
489 
490 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
491 	if (ret < 0)
492 		goto out;
493 
494 	if (info->drv_data->alarm_enable_reg) {
495 		if (map[REG_RTC_AE1] == REG_RTC_NONE) {
496 			ret = -EINVAL;
497 			dev_err(info->dev,
498 				"alarm enable register not set(%d)\n", ret);
499 			goto out;
500 		}
501 
502 		ret = regmap_write(info->rtc_regmap, map[REG_RTC_AE1], 0);
503 	} else {
504 		ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
505 				       data, ARRAY_SIZE(data));
506 		if (ret < 0) {
507 			dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
508 			goto out;
509 		}
510 
511 		max77686_rtc_data_to_tm(data, &tm, info);
512 
513 		for (i = 0; i < ARRAY_SIZE(data); i++)
514 			data[i] &= ~ALARM_ENABLE_MASK;
515 
516 		ret = regmap_bulk_write(info->rtc_regmap, map[REG_ALARM1_SEC],
517 					data, ARRAY_SIZE(data));
518 	}
519 
520 	if (ret < 0) {
521 		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
522 		goto out;
523 	}
524 
525 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
526 out:
527 	return ret;
528 }
529 
530 static int max77686_rtc_start_alarm(struct max77686_rtc_info *info)
531 {
532 	u8 data[RTC_NR_TIME];
533 	int ret;
534 	struct rtc_time tm;
535 	const unsigned int *map = info->drv_data->map;
536 
537 	if (!mutex_is_locked(&info->lock))
538 		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
539 
540 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
541 	if (ret < 0)
542 		goto out;
543 
544 	if (info->drv_data->alarm_enable_reg) {
545 		ret = regmap_write(info->rtc_regmap, map[REG_RTC_AE1],
546 				   MAX77802_ALARM_ENABLE_VALUE);
547 	} else {
548 		ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
549 				       data, ARRAY_SIZE(data));
550 		if (ret < 0) {
551 			dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
552 			goto out;
553 		}
554 
555 		max77686_rtc_data_to_tm(data, &tm, info);
556 
557 		data[RTC_SEC] |= (1 << ALARM_ENABLE_SHIFT);
558 		data[RTC_MIN] |= (1 << ALARM_ENABLE_SHIFT);
559 		data[RTC_HOUR] |= (1 << ALARM_ENABLE_SHIFT);
560 		data[RTC_WEEKDAY] &= ~ALARM_ENABLE_MASK;
561 		if (data[RTC_MONTH] & 0xf)
562 			data[RTC_MONTH] |= (1 << ALARM_ENABLE_SHIFT);
563 		if (data[RTC_YEAR] & info->drv_data->mask)
564 			data[RTC_YEAR] |= (1 << ALARM_ENABLE_SHIFT);
565 		if (data[RTC_DATE] & 0x1f)
566 			data[RTC_DATE] |= (1 << ALARM_ENABLE_SHIFT);
567 
568 		ret = regmap_bulk_write(info->rtc_regmap, map[REG_ALARM1_SEC],
569 					data, ARRAY_SIZE(data));
570 	}
571 
572 	if (ret < 0) {
573 		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
574 		goto out;
575 	}
576 
577 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
578 out:
579 	return ret;
580 }
581 
582 static int max77686_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
583 {
584 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
585 	u8 data[RTC_NR_TIME];
586 	int ret;
587 
588 	ret = max77686_rtc_tm_to_data(&alrm->time, data, info);
589 	if (ret < 0)
590 		return ret;
591 
592 	mutex_lock(&info->lock);
593 
594 	ret = max77686_rtc_stop_alarm(info);
595 	if (ret < 0)
596 		goto out;
597 
598 	ret = regmap_bulk_write(info->rtc_regmap,
599 				info->drv_data->map[REG_ALARM1_SEC],
600 				data, ARRAY_SIZE(data));
601 
602 	if (ret < 0) {
603 		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
604 		goto out;
605 	}
606 
607 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
608 	if (ret < 0)
609 		goto out;
610 
611 	if (alrm->enabled)
612 		ret = max77686_rtc_start_alarm(info);
613 out:
614 	mutex_unlock(&info->lock);
615 	return ret;
616 }
617 
618 static int max77686_rtc_alarm_irq_enable(struct device *dev,
619 					 unsigned int enabled)
620 {
621 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
622 	int ret;
623 
624 	mutex_lock(&info->lock);
625 	if (enabled)
626 		ret = max77686_rtc_start_alarm(info);
627 	else
628 		ret = max77686_rtc_stop_alarm(info);
629 	mutex_unlock(&info->lock);
630 
631 	return ret;
632 }
633 
634 static irqreturn_t max77686_rtc_alarm_irq(int irq, void *data)
635 {
636 	struct max77686_rtc_info *info = data;
637 
638 	dev_dbg(info->dev, "RTC alarm IRQ: %d\n", irq);
639 
640 	rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
641 
642 	return IRQ_HANDLED;
643 }
644 
645 static const struct rtc_class_ops max77686_rtc_ops = {
646 	.read_time = max77686_rtc_read_time,
647 	.set_time = max77686_rtc_set_time,
648 	.read_alarm = max77686_rtc_read_alarm,
649 	.set_alarm = max77686_rtc_set_alarm,
650 	.alarm_irq_enable = max77686_rtc_alarm_irq_enable,
651 };
652 
653 static int max77686_rtc_init_reg(struct max77686_rtc_info *info)
654 {
655 	u8 data[2];
656 	int ret;
657 
658 	/* Set RTC control register : Binary mode, 24hour mdoe */
659 	data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
660 	data[1] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
661 
662 	info->rtc_24hr_mode = 1;
663 
664 	ret = regmap_bulk_write(info->rtc_regmap,
665 				info->drv_data->map[REG_RTC_CONTROLM],
666 				data, ARRAY_SIZE(data));
667 	if (ret < 0) {
668 		dev_err(info->dev, "Fail to write controlm reg(%d)\n", ret);
669 		return ret;
670 	}
671 
672 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
673 	return ret;
674 }
675 
676 static int max77686_init_rtc_regmap(struct max77686_rtc_info *info)
677 {
678 	struct device *parent = info->dev->parent;
679 	struct i2c_client *parent_i2c = to_i2c_client(parent);
680 	int ret;
681 
682 	if (info->drv_data->rtc_irq_from_platform) {
683 		struct platform_device *pdev = to_platform_device(info->dev);
684 
685 		info->rtc_irq = platform_get_irq(pdev, 0);
686 		if (info->rtc_irq < 0)
687 			return info->rtc_irq;
688 	} else {
689 		info->rtc_irq =  parent_i2c->irq;
690 	}
691 
692 	info->regmap = dev_get_regmap(parent, NULL);
693 	if (!info->regmap) {
694 		dev_err(info->dev, "Failed to get rtc regmap\n");
695 		return -ENODEV;
696 	}
697 
698 	if (info->drv_data->rtc_i2c_addr == MAX77686_INVALID_I2C_ADDR) {
699 		info->rtc_regmap = info->regmap;
700 		goto add_rtc_irq;
701 	}
702 
703 	info->rtc = devm_i2c_new_dummy_device(info->dev, parent_i2c->adapter,
704 					      info->drv_data->rtc_i2c_addr);
705 	if (IS_ERR(info->rtc)) {
706 		dev_err(info->dev, "Failed to allocate I2C device for RTC\n");
707 		return PTR_ERR(info->rtc);
708 	}
709 
710 	info->rtc_regmap = devm_regmap_init_i2c(info->rtc,
711 						info->drv_data->regmap_config);
712 	if (IS_ERR(info->rtc_regmap)) {
713 		ret = PTR_ERR(info->rtc_regmap);
714 		dev_err(info->dev, "Failed to allocate RTC regmap: %d\n", ret);
715 		return ret;
716 	}
717 
718 add_rtc_irq:
719 	ret = regmap_add_irq_chip(info->rtc_regmap, info->rtc_irq,
720 				  IRQF_TRIGGER_FALLING | IRQF_ONESHOT |
721 				  IRQF_SHARED, 0, info->drv_data->rtc_irq_chip,
722 				  &info->rtc_irq_data);
723 	if (ret < 0) {
724 		dev_err(info->dev, "Failed to add RTC irq chip: %d\n", ret);
725 		return ret;
726 	}
727 
728 	return 0;
729 }
730 
731 static int max77686_rtc_probe(struct platform_device *pdev)
732 {
733 	struct max77686_rtc_info *info;
734 	const struct platform_device_id *id = platform_get_device_id(pdev);
735 	int ret;
736 
737 	info = devm_kzalloc(&pdev->dev, sizeof(struct max77686_rtc_info),
738 			    GFP_KERNEL);
739 	if (!info)
740 		return -ENOMEM;
741 
742 	mutex_init(&info->lock);
743 	info->dev = &pdev->dev;
744 	info->drv_data = (const struct max77686_rtc_driver_data *)
745 		id->driver_data;
746 
747 	ret = max77686_init_rtc_regmap(info);
748 	if (ret < 0)
749 		return ret;
750 
751 	platform_set_drvdata(pdev, info);
752 
753 	ret = max77686_rtc_init_reg(info);
754 	if (ret < 0) {
755 		dev_err(&pdev->dev, "Failed to initialize RTC reg:%d\n", ret);
756 		goto err_rtc;
757 	}
758 
759 	device_init_wakeup(&pdev->dev, 1);
760 
761 	info->rtc_dev = devm_rtc_device_register(&pdev->dev, id->name,
762 					&max77686_rtc_ops, THIS_MODULE);
763 
764 	if (IS_ERR(info->rtc_dev)) {
765 		ret = PTR_ERR(info->rtc_dev);
766 		dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
767 		if (ret == 0)
768 			ret = -EINVAL;
769 		goto err_rtc;
770 	}
771 
772 	info->virq = regmap_irq_get_virq(info->rtc_irq_data,
773 					 MAX77686_RTCIRQ_RTCA1);
774 	if (info->virq <= 0) {
775 		ret = -ENXIO;
776 		goto err_rtc;
777 	}
778 
779 	ret = request_threaded_irq(info->virq, NULL, max77686_rtc_alarm_irq, 0,
780 				   "rtc-alarm1", info);
781 	if (ret < 0) {
782 		dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
783 			info->virq, ret);
784 		goto err_rtc;
785 	}
786 
787 	return 0;
788 
789 err_rtc:
790 	regmap_del_irq_chip(info->rtc_irq, info->rtc_irq_data);
791 
792 	return ret;
793 }
794 
795 static int max77686_rtc_remove(struct platform_device *pdev)
796 {
797 	struct max77686_rtc_info *info = platform_get_drvdata(pdev);
798 
799 	free_irq(info->virq, info);
800 	regmap_del_irq_chip(info->rtc_irq, info->rtc_irq_data);
801 
802 	return 0;
803 }
804 
805 #ifdef CONFIG_PM_SLEEP
806 static int max77686_rtc_suspend(struct device *dev)
807 {
808 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
809 	int ret = 0;
810 
811 	if (device_may_wakeup(dev)) {
812 		struct max77686_rtc_info *info = dev_get_drvdata(dev);
813 
814 		ret = enable_irq_wake(info->virq);
815 	}
816 
817 	/*
818 	 * If the main IRQ (not virtual) is the parent IRQ, then it must be
819 	 * disabled during suspend because if it happens while suspended it
820 	 * will be handled before resuming I2C.
821 	 *
822 	 * Since Main IRQ is shared, all its users should disable it to be sure
823 	 * it won't fire while one of them is still suspended.
824 	 */
825 	if (!info->drv_data->rtc_irq_from_platform)
826 		disable_irq(info->rtc_irq);
827 
828 	return ret;
829 }
830 
831 static int max77686_rtc_resume(struct device *dev)
832 {
833 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
834 
835 	if (!info->drv_data->rtc_irq_from_platform)
836 		enable_irq(info->rtc_irq);
837 
838 	if (device_may_wakeup(dev)) {
839 		struct max77686_rtc_info *info = dev_get_drvdata(dev);
840 
841 		return disable_irq_wake(info->virq);
842 	}
843 
844 	return 0;
845 }
846 #endif
847 
848 static SIMPLE_DEV_PM_OPS(max77686_rtc_pm_ops,
849 			 max77686_rtc_suspend, max77686_rtc_resume);
850 
851 static const struct platform_device_id rtc_id[] = {
852 	{ "max77686-rtc", .driver_data = (kernel_ulong_t)&max77686_drv_data, },
853 	{ "max77802-rtc", .driver_data = (kernel_ulong_t)&max77802_drv_data, },
854 	{ "max77620-rtc", .driver_data = (kernel_ulong_t)&max77620_drv_data, },
855 	{},
856 };
857 MODULE_DEVICE_TABLE(platform, rtc_id);
858 
859 static struct platform_driver max77686_rtc_driver = {
860 	.driver		= {
861 		.name	= "max77686-rtc",
862 		.pm	= &max77686_rtc_pm_ops,
863 	},
864 	.probe		= max77686_rtc_probe,
865 	.remove		= max77686_rtc_remove,
866 	.id_table	= rtc_id,
867 };
868 
869 module_platform_driver(max77686_rtc_driver);
870 
871 MODULE_DESCRIPTION("Maxim MAX77686 RTC driver");
872 MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
873 MODULE_LICENSE("GPL");
874