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 MAX77714_I2C_ADDR_RTC		0x48
23 #define MAX77686_INVALID_I2C_ADDR	(-1)
24 
25 /* Define non existing register */
26 #define MAX77686_INVALID_REG		(-1)
27 
28 /* RTC Control Register */
29 #define BCD_EN_SHIFT			0
30 #define BCD_EN_MASK			BIT(BCD_EN_SHIFT)
31 #define MODEL24_SHIFT			1
32 #define MODEL24_MASK			BIT(MODEL24_SHIFT)
33 /* RTC Update Register1 */
34 #define RTC_UDR_SHIFT			0
35 #define RTC_UDR_MASK			BIT(RTC_UDR_SHIFT)
36 #define RTC_RBUDR_SHIFT			4
37 #define RTC_RBUDR_MASK			BIT(RTC_RBUDR_SHIFT)
38 /* RTC Alarm Enable */
39 #define ALARM_ENABLE_SHIFT		7
40 #define ALARM_ENABLE_MASK		BIT(ALARM_ENABLE_SHIFT)
41 
42 #define REG_RTC_NONE			0xdeadbeef
43 
44 /*
45  * MAX77802 has separate register (RTCAE1) for alarm enable instead
46  * using 1 bit from registers RTC{SEC,MIN,HOUR,DAY,MONTH,YEAR,DATE}
47  * as in done in MAX77686.
48  */
49 #define MAX77802_ALARM_ENABLE_VALUE	0x77
50 
51 enum {
52 	RTC_SEC = 0,
53 	RTC_MIN,
54 	RTC_HOUR,
55 	RTC_WEEKDAY,
56 	RTC_MONTH,
57 	RTC_YEAR,
58 	RTC_MONTHDAY,
59 	RTC_NR_TIME
60 };
61 
62 /**
63  * struct max77686_rtc_driver_data - model-specific configuration
64  * @delay: Minimum usecs needed for a RTC update
65  * @mask: Mask used to read RTC registers value
66  * @map: Registers offset to I2C addresses map
67  * @alarm_enable_reg: Has a separate alarm enable register?
68  * @rtc_i2c_addr: I2C address for RTC block
69  * @rtc_irq_from_platform: RTC interrupt via platform resource
70  * @alarm_pending_status_reg: Pending alarm status register
71  * @rtc_irq_chip: RTC IRQ CHIP for regmap
72  * @regmap_config: regmap configuration for the chip
73  */
74 struct max77686_rtc_driver_data {
75 	unsigned long		delay;
76 	u8			mask;
77 	const unsigned int	*map;
78 	bool			alarm_enable_reg;
79 	int			rtc_i2c_addr;
80 	bool			rtc_irq_from_platform;
81 	int			alarm_pending_status_reg;
82 	const struct regmap_irq_chip *rtc_irq_chip;
83 	const struct regmap_config *regmap_config;
84 };
85 
86 struct max77686_rtc_info {
87 	struct device		*dev;
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 };
100 
101 enum MAX77686_RTC_OP {
102 	MAX77686_RTC_WRITE,
103 	MAX77686_RTC_READ,
104 };
105 
106 /* These are not registers but just offsets that are mapped to addresses */
107 enum max77686_rtc_reg_offset {
108 	REG_RTC_CONTROLM = 0,
109 	REG_RTC_CONTROL,
110 	REG_RTC_UPDATE0,
111 	REG_WTSR_SMPL_CNTL,
112 	REG_RTC_SEC,
113 	REG_RTC_MIN,
114 	REG_RTC_HOUR,
115 	REG_RTC_WEEKDAY,
116 	REG_RTC_MONTH,
117 	REG_RTC_YEAR,
118 	REG_RTC_MONTHDAY,
119 	REG_ALARM1_SEC,
120 	REG_ALARM1_MIN,
121 	REG_ALARM1_HOUR,
122 	REG_ALARM1_WEEKDAY,
123 	REG_ALARM1_MONTH,
124 	REG_ALARM1_YEAR,
125 	REG_ALARM1_DATE,
126 	REG_ALARM2_SEC,
127 	REG_ALARM2_MIN,
128 	REG_ALARM2_HOUR,
129 	REG_ALARM2_WEEKDAY,
130 	REG_ALARM2_MONTH,
131 	REG_ALARM2_YEAR,
132 	REG_ALARM2_DATE,
133 	REG_RTC_AE1,
134 	REG_RTC_END,
135 };
136 
137 /* Maps RTC registers offset to the MAX77686 register addresses */
138 static const unsigned int max77686_map[REG_RTC_END] = {
139 	[REG_RTC_CONTROLM]   = MAX77686_RTC_CONTROLM,
140 	[REG_RTC_CONTROL]    = MAX77686_RTC_CONTROL,
141 	[REG_RTC_UPDATE0]    = MAX77686_RTC_UPDATE0,
142 	[REG_WTSR_SMPL_CNTL] = MAX77686_WTSR_SMPL_CNTL,
143 	[REG_RTC_SEC]        = MAX77686_RTC_SEC,
144 	[REG_RTC_MIN]        = MAX77686_RTC_MIN,
145 	[REG_RTC_HOUR]       = MAX77686_RTC_HOUR,
146 	[REG_RTC_WEEKDAY]    = MAX77686_RTC_WEEKDAY,
147 	[REG_RTC_MONTH]      = MAX77686_RTC_MONTH,
148 	[REG_RTC_YEAR]       = MAX77686_RTC_YEAR,
149 	[REG_RTC_MONTHDAY]   = MAX77686_RTC_MONTHDAY,
150 	[REG_ALARM1_SEC]     = MAX77686_ALARM1_SEC,
151 	[REG_ALARM1_MIN]     = MAX77686_ALARM1_MIN,
152 	[REG_ALARM1_HOUR]    = MAX77686_ALARM1_HOUR,
153 	[REG_ALARM1_WEEKDAY] = MAX77686_ALARM1_WEEKDAY,
154 	[REG_ALARM1_MONTH]   = MAX77686_ALARM1_MONTH,
155 	[REG_ALARM1_YEAR]    = MAX77686_ALARM1_YEAR,
156 	[REG_ALARM1_DATE]    = MAX77686_ALARM1_DATE,
157 	[REG_ALARM2_SEC]     = MAX77686_ALARM2_SEC,
158 	[REG_ALARM2_MIN]     = MAX77686_ALARM2_MIN,
159 	[REG_ALARM2_HOUR]    = MAX77686_ALARM2_HOUR,
160 	[REG_ALARM2_WEEKDAY] = MAX77686_ALARM2_WEEKDAY,
161 	[REG_ALARM2_MONTH]   = MAX77686_ALARM2_MONTH,
162 	[REG_ALARM2_YEAR]    = MAX77686_ALARM2_YEAR,
163 	[REG_ALARM2_DATE]    = MAX77686_ALARM2_DATE,
164 	[REG_RTC_AE1]	     = REG_RTC_NONE,
165 };
166 
167 static const struct regmap_irq max77686_rtc_irqs[] = {
168 	/* RTC interrupts */
169 	REGMAP_IRQ_REG(0, 0, MAX77686_RTCINT_RTC60S_MSK),
170 	REGMAP_IRQ_REG(1, 0, MAX77686_RTCINT_RTCA1_MSK),
171 	REGMAP_IRQ_REG(2, 0, MAX77686_RTCINT_RTCA2_MSK),
172 	REGMAP_IRQ_REG(3, 0, MAX77686_RTCINT_SMPL_MSK),
173 	REGMAP_IRQ_REG(4, 0, MAX77686_RTCINT_RTC1S_MSK),
174 	REGMAP_IRQ_REG(5, 0, MAX77686_RTCINT_WTSR_MSK),
175 };
176 
177 static const struct regmap_irq_chip max77686_rtc_irq_chip = {
178 	.name		= "max77686-rtc",
179 	.status_base	= MAX77686_RTC_INT,
180 	.mask_base	= MAX77686_RTC_INTM,
181 	.num_regs	= 1,
182 	.irqs		= max77686_rtc_irqs,
183 	.num_irqs	= ARRAY_SIZE(max77686_rtc_irqs),
184 };
185 
186 static const struct regmap_config max77686_rtc_regmap_config = {
187 	.reg_bits = 8,
188 	.val_bits = 8,
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 	.regmap_config = &max77686_rtc_regmap_config,
201 };
202 
203 static const struct regmap_irq_chip max77714_rtc_irq_chip = {
204 	.name		= "max77714-rtc",
205 	.status_base	= MAX77686_RTC_INT,
206 	.mask_base	= MAX77686_RTC_INTM,
207 	.num_regs	= 1,
208 	.irqs		= max77686_rtc_irqs,
209 	.num_irqs	= ARRAY_SIZE(max77686_rtc_irqs) - 1, /* no WTSR on 77714 */
210 };
211 
212 static const struct max77686_rtc_driver_data max77714_drv_data = {
213 	.delay = 16000,
214 	.mask  = 0x7f,
215 	.map   = max77686_map,
216 	.alarm_enable_reg = false,
217 	.rtc_irq_from_platform = false,
218 	/* On MAX77714 RTCA1 is BIT 1 of RTCINT (0x00). Not supported by this driver. */
219 	.alarm_pending_status_reg = MAX77686_INVALID_REG,
220 	.rtc_i2c_addr = MAX77714_I2C_ADDR_RTC,
221 	.rtc_irq_chip = &max77714_rtc_irq_chip,
222 	.regmap_config = &max77686_rtc_regmap_config,
223 };
224 
225 static const struct regmap_config max77620_rtc_regmap_config = {
226 	.reg_bits = 8,
227 	.val_bits = 8,
228 	.use_single_write = true,
229 };
230 
231 static const struct max77686_rtc_driver_data max77620_drv_data = {
232 	.delay = 16000,
233 	.mask  = 0x7f,
234 	.map   = max77686_map,
235 	.alarm_enable_reg  = false,
236 	.rtc_irq_from_platform = true,
237 	.alarm_pending_status_reg = MAX77686_INVALID_REG,
238 	.rtc_i2c_addr = MAX77620_I2C_ADDR_RTC,
239 	.rtc_irq_chip = &max77686_rtc_irq_chip,
240 	.regmap_config = &max77620_rtc_regmap_config,
241 };
242 
243 static const unsigned int max77802_map[REG_RTC_END] = {
244 	[REG_RTC_CONTROLM]   = MAX77802_RTC_CONTROLM,
245 	[REG_RTC_CONTROL]    = MAX77802_RTC_CONTROL,
246 	[REG_RTC_UPDATE0]    = MAX77802_RTC_UPDATE0,
247 	[REG_WTSR_SMPL_CNTL] = MAX77802_WTSR_SMPL_CNTL,
248 	[REG_RTC_SEC]        = MAX77802_RTC_SEC,
249 	[REG_RTC_MIN]        = MAX77802_RTC_MIN,
250 	[REG_RTC_HOUR]       = MAX77802_RTC_HOUR,
251 	[REG_RTC_WEEKDAY]    = MAX77802_RTC_WEEKDAY,
252 	[REG_RTC_MONTH]      = MAX77802_RTC_MONTH,
253 	[REG_RTC_YEAR]       = MAX77802_RTC_YEAR,
254 	[REG_RTC_MONTHDAY]   = MAX77802_RTC_MONTHDAY,
255 	[REG_ALARM1_SEC]     = MAX77802_ALARM1_SEC,
256 	[REG_ALARM1_MIN]     = MAX77802_ALARM1_MIN,
257 	[REG_ALARM1_HOUR]    = MAX77802_ALARM1_HOUR,
258 	[REG_ALARM1_WEEKDAY] = MAX77802_ALARM1_WEEKDAY,
259 	[REG_ALARM1_MONTH]   = MAX77802_ALARM1_MONTH,
260 	[REG_ALARM1_YEAR]    = MAX77802_ALARM1_YEAR,
261 	[REG_ALARM1_DATE]    = MAX77802_ALARM1_DATE,
262 	[REG_ALARM2_SEC]     = MAX77802_ALARM2_SEC,
263 	[REG_ALARM2_MIN]     = MAX77802_ALARM2_MIN,
264 	[REG_ALARM2_HOUR]    = MAX77802_ALARM2_HOUR,
265 	[REG_ALARM2_WEEKDAY] = MAX77802_ALARM2_WEEKDAY,
266 	[REG_ALARM2_MONTH]   = MAX77802_ALARM2_MONTH,
267 	[REG_ALARM2_YEAR]    = MAX77802_ALARM2_YEAR,
268 	[REG_ALARM2_DATE]    = MAX77802_ALARM2_DATE,
269 	[REG_RTC_AE1]	     = MAX77802_RTC_AE1,
270 };
271 
272 static const struct regmap_irq_chip max77802_rtc_irq_chip = {
273 	.name		= "max77802-rtc",
274 	.status_base	= MAX77802_RTC_INT,
275 	.mask_base	= MAX77802_RTC_INTM,
276 	.num_regs	= 1,
277 	.irqs		= max77686_rtc_irqs, /* same masks as 77686 */
278 	.num_irqs	= ARRAY_SIZE(max77686_rtc_irqs),
279 };
280 
281 static const struct max77686_rtc_driver_data max77802_drv_data = {
282 	.delay = 200,
283 	.mask  = 0xff,
284 	.map   = max77802_map,
285 	.alarm_enable_reg  = true,
286 	.rtc_irq_from_platform = false,
287 	.alarm_pending_status_reg = MAX77686_REG_STATUS2,
288 	.rtc_i2c_addr = MAX77686_INVALID_I2C_ADDR,
289 	.rtc_irq_chip = &max77802_rtc_irq_chip,
290 };
291 
292 static void max77686_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
293 				    struct max77686_rtc_info *info)
294 {
295 	u8 mask = info->drv_data->mask;
296 
297 	tm->tm_sec = data[RTC_SEC] & mask;
298 	tm->tm_min = data[RTC_MIN] & mask;
299 	tm->tm_hour = data[RTC_HOUR] & 0x1f;
300 
301 	/* Only a single bit is set in data[], so fls() would be equivalent */
302 	tm->tm_wday = ffs(data[RTC_WEEKDAY] & mask) - 1;
303 	tm->tm_mday = data[RTC_MONTHDAY] & 0x1f;
304 	tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1;
305 	tm->tm_year = data[RTC_YEAR] & mask;
306 	tm->tm_yday = 0;
307 	tm->tm_isdst = 0;
308 
309 	/*
310 	 * MAX77686 uses 1 bit from sec/min/hour/etc RTC registers and the
311 	 * year values are just 0..99 so add 100 to support up to 2099.
312 	 */
313 	if (!info->drv_data->alarm_enable_reg)
314 		tm->tm_year += 100;
315 }
316 
317 static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data,
318 				   struct max77686_rtc_info *info)
319 {
320 	data[RTC_SEC] = tm->tm_sec;
321 	data[RTC_MIN] = tm->tm_min;
322 	data[RTC_HOUR] = tm->tm_hour;
323 	data[RTC_WEEKDAY] = 1 << tm->tm_wday;
324 	data[RTC_MONTHDAY] = tm->tm_mday;
325 	data[RTC_MONTH] = tm->tm_mon + 1;
326 
327 	if (info->drv_data->alarm_enable_reg) {
328 		data[RTC_YEAR] = tm->tm_year;
329 		return 0;
330 	}
331 
332 	data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
333 
334 	if (tm->tm_year < 100) {
335 		dev_err(info->dev, "RTC cannot handle the year %d.\n",
336 			1900 + tm->tm_year);
337 		return -EINVAL;
338 	}
339 
340 	return 0;
341 }
342 
343 static int max77686_rtc_update(struct max77686_rtc_info *info,
344 			       enum MAX77686_RTC_OP op)
345 {
346 	int ret;
347 	unsigned int data;
348 	unsigned long delay = info->drv_data->delay;
349 
350 	if (op == MAX77686_RTC_WRITE)
351 		data = 1 << RTC_UDR_SHIFT;
352 	else
353 		data = 1 << RTC_RBUDR_SHIFT;
354 
355 	ret = regmap_update_bits(info->rtc_regmap,
356 				 info->drv_data->map[REG_RTC_UPDATE0],
357 				 data, data);
358 	if (ret < 0)
359 		dev_err(info->dev, "Fail to write update reg(ret=%d, data=0x%x)\n",
360 			ret, data);
361 	else {
362 		/* Minimum delay required before RTC update. */
363 		usleep_range(delay, delay * 2);
364 	}
365 
366 	return ret;
367 }
368 
369 static int max77686_rtc_read_time(struct device *dev, struct rtc_time *tm)
370 {
371 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
372 	u8 data[RTC_NR_TIME];
373 	int ret;
374 
375 	mutex_lock(&info->lock);
376 
377 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
378 	if (ret < 0)
379 		goto out;
380 
381 	ret = regmap_bulk_read(info->rtc_regmap,
382 			       info->drv_data->map[REG_RTC_SEC],
383 			       data, ARRAY_SIZE(data));
384 	if (ret < 0) {
385 		dev_err(info->dev, "Fail to read time reg(%d)\n", ret);
386 		goto out;
387 	}
388 
389 	max77686_rtc_data_to_tm(data, tm, info);
390 
391 out:
392 	mutex_unlock(&info->lock);
393 	return ret;
394 }
395 
396 static int max77686_rtc_set_time(struct device *dev, struct rtc_time *tm)
397 {
398 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
399 	u8 data[RTC_NR_TIME];
400 	int ret;
401 
402 	ret = max77686_rtc_tm_to_data(tm, data, info);
403 	if (ret < 0)
404 		return ret;
405 
406 	mutex_lock(&info->lock);
407 
408 	ret = regmap_bulk_write(info->rtc_regmap,
409 				info->drv_data->map[REG_RTC_SEC],
410 				data, ARRAY_SIZE(data));
411 	if (ret < 0) {
412 		dev_err(info->dev, "Fail to write time reg(%d)\n", ret);
413 		goto out;
414 	}
415 
416 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
417 
418 out:
419 	mutex_unlock(&info->lock);
420 	return ret;
421 }
422 
423 static int max77686_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
424 {
425 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
426 	u8 data[RTC_NR_TIME];
427 	unsigned int val;
428 	const unsigned int *map = info->drv_data->map;
429 	int i, ret;
430 
431 	mutex_lock(&info->lock);
432 
433 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
434 	if (ret < 0)
435 		goto out;
436 
437 	ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
438 			       data, ARRAY_SIZE(data));
439 	if (ret < 0) {
440 		dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
441 		goto out;
442 	}
443 
444 	max77686_rtc_data_to_tm(data, &alrm->time, info);
445 
446 	alrm->enabled = 0;
447 
448 	if (info->drv_data->alarm_enable_reg) {
449 		if (map[REG_RTC_AE1] == REG_RTC_NONE) {
450 			ret = -EINVAL;
451 			dev_err(info->dev,
452 				"alarm enable register not set(%d)\n", ret);
453 			goto out;
454 		}
455 
456 		ret = regmap_read(info->rtc_regmap, map[REG_RTC_AE1], &val);
457 		if (ret < 0) {
458 			dev_err(info->dev,
459 				"fail to read alarm enable(%d)\n", ret);
460 			goto out;
461 		}
462 
463 		if (val)
464 			alrm->enabled = 1;
465 	} else {
466 		for (i = 0; i < ARRAY_SIZE(data); i++) {
467 			if (data[i] & ALARM_ENABLE_MASK) {
468 				alrm->enabled = 1;
469 				break;
470 			}
471 		}
472 	}
473 
474 	alrm->pending = 0;
475 
476 	if (info->drv_data->alarm_pending_status_reg == MAX77686_INVALID_REG)
477 		goto out;
478 
479 	ret = regmap_read(info->regmap,
480 			  info->drv_data->alarm_pending_status_reg, &val);
481 	if (ret < 0) {
482 		dev_err(info->dev,
483 			"Fail to read alarm pending status reg(%d)\n", ret);
484 		goto out;
485 	}
486 
487 	if (val & (1 << 4)) /* RTCA1 */
488 		alrm->pending = 1;
489 
490 out:
491 	mutex_unlock(&info->lock);
492 	return ret;
493 }
494 
495 static int max77686_rtc_stop_alarm(struct max77686_rtc_info *info)
496 {
497 	u8 data[RTC_NR_TIME];
498 	int ret, i;
499 	struct rtc_time tm;
500 	const unsigned int *map = info->drv_data->map;
501 
502 	if (!mutex_is_locked(&info->lock))
503 		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
504 
505 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
506 	if (ret < 0)
507 		goto out;
508 
509 	if (info->drv_data->alarm_enable_reg) {
510 		if (map[REG_RTC_AE1] == REG_RTC_NONE) {
511 			ret = -EINVAL;
512 			dev_err(info->dev,
513 				"alarm enable register not set(%d)\n", ret);
514 			goto out;
515 		}
516 
517 		ret = regmap_write(info->rtc_regmap, map[REG_RTC_AE1], 0);
518 	} else {
519 		ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
520 				       data, ARRAY_SIZE(data));
521 		if (ret < 0) {
522 			dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
523 			goto out;
524 		}
525 
526 		max77686_rtc_data_to_tm(data, &tm, info);
527 
528 		for (i = 0; i < ARRAY_SIZE(data); i++)
529 			data[i] &= ~ALARM_ENABLE_MASK;
530 
531 		ret = regmap_bulk_write(info->rtc_regmap, map[REG_ALARM1_SEC],
532 					data, ARRAY_SIZE(data));
533 	}
534 
535 	if (ret < 0) {
536 		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
537 		goto out;
538 	}
539 
540 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
541 out:
542 	return ret;
543 }
544 
545 static int max77686_rtc_start_alarm(struct max77686_rtc_info *info)
546 {
547 	u8 data[RTC_NR_TIME];
548 	int ret;
549 	struct rtc_time tm;
550 	const unsigned int *map = info->drv_data->map;
551 
552 	if (!mutex_is_locked(&info->lock))
553 		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
554 
555 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
556 	if (ret < 0)
557 		goto out;
558 
559 	if (info->drv_data->alarm_enable_reg) {
560 		ret = regmap_write(info->rtc_regmap, map[REG_RTC_AE1],
561 				   MAX77802_ALARM_ENABLE_VALUE);
562 	} else {
563 		ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
564 				       data, ARRAY_SIZE(data));
565 		if (ret < 0) {
566 			dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
567 			goto out;
568 		}
569 
570 		max77686_rtc_data_to_tm(data, &tm, info);
571 
572 		data[RTC_SEC] |= (1 << ALARM_ENABLE_SHIFT);
573 		data[RTC_MIN] |= (1 << ALARM_ENABLE_SHIFT);
574 		data[RTC_HOUR] |= (1 << ALARM_ENABLE_SHIFT);
575 		data[RTC_WEEKDAY] &= ~ALARM_ENABLE_MASK;
576 		if (data[RTC_MONTH] & 0xf)
577 			data[RTC_MONTH] |= (1 << ALARM_ENABLE_SHIFT);
578 		if (data[RTC_YEAR] & info->drv_data->mask)
579 			data[RTC_YEAR] |= (1 << ALARM_ENABLE_SHIFT);
580 		if (data[RTC_MONTHDAY] & 0x1f)
581 			data[RTC_MONTHDAY] |= (1 << ALARM_ENABLE_SHIFT);
582 
583 		ret = regmap_bulk_write(info->rtc_regmap, map[REG_ALARM1_SEC],
584 					data, ARRAY_SIZE(data));
585 	}
586 
587 	if (ret < 0) {
588 		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
589 		goto out;
590 	}
591 
592 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
593 out:
594 	return ret;
595 }
596 
597 static int max77686_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
598 {
599 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
600 	u8 data[RTC_NR_TIME];
601 	int ret;
602 
603 	ret = max77686_rtc_tm_to_data(&alrm->time, data, info);
604 	if (ret < 0)
605 		return ret;
606 
607 	mutex_lock(&info->lock);
608 
609 	ret = max77686_rtc_stop_alarm(info);
610 	if (ret < 0)
611 		goto out;
612 
613 	ret = regmap_bulk_write(info->rtc_regmap,
614 				info->drv_data->map[REG_ALARM1_SEC],
615 				data, ARRAY_SIZE(data));
616 
617 	if (ret < 0) {
618 		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
619 		goto out;
620 	}
621 
622 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
623 	if (ret < 0)
624 		goto out;
625 
626 	if (alrm->enabled)
627 		ret = max77686_rtc_start_alarm(info);
628 out:
629 	mutex_unlock(&info->lock);
630 	return ret;
631 }
632 
633 static int max77686_rtc_alarm_irq_enable(struct device *dev,
634 					 unsigned int enabled)
635 {
636 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
637 	int ret;
638 
639 	mutex_lock(&info->lock);
640 	if (enabled)
641 		ret = max77686_rtc_start_alarm(info);
642 	else
643 		ret = max77686_rtc_stop_alarm(info);
644 	mutex_unlock(&info->lock);
645 
646 	return ret;
647 }
648 
649 static irqreturn_t max77686_rtc_alarm_irq(int irq, void *data)
650 {
651 	struct max77686_rtc_info *info = data;
652 
653 	dev_dbg(info->dev, "RTC alarm IRQ: %d\n", irq);
654 
655 	rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
656 
657 	return IRQ_HANDLED;
658 }
659 
660 static const struct rtc_class_ops max77686_rtc_ops = {
661 	.read_time = max77686_rtc_read_time,
662 	.set_time = max77686_rtc_set_time,
663 	.read_alarm = max77686_rtc_read_alarm,
664 	.set_alarm = max77686_rtc_set_alarm,
665 	.alarm_irq_enable = max77686_rtc_alarm_irq_enable,
666 };
667 
668 static int max77686_rtc_init_reg(struct max77686_rtc_info *info)
669 {
670 	u8 data[2];
671 	int ret;
672 
673 	/* Set RTC control register : Binary mode, 24hour mdoe */
674 	data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
675 	data[1] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
676 
677 	ret = regmap_bulk_write(info->rtc_regmap,
678 				info->drv_data->map[REG_RTC_CONTROLM],
679 				data, ARRAY_SIZE(data));
680 	if (ret < 0) {
681 		dev_err(info->dev, "Fail to write controlm reg(%d)\n", ret);
682 		return ret;
683 	}
684 
685 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
686 	return ret;
687 }
688 
689 static int max77686_init_rtc_regmap(struct max77686_rtc_info *info)
690 {
691 	struct device *parent = info->dev->parent;
692 	struct i2c_client *parent_i2c = to_i2c_client(parent);
693 	struct i2c_client *client;
694 	int ret;
695 
696 	if (info->drv_data->rtc_irq_from_platform) {
697 		struct platform_device *pdev = to_platform_device(info->dev);
698 
699 		info->rtc_irq = platform_get_irq(pdev, 0);
700 		if (info->rtc_irq < 0)
701 			return info->rtc_irq;
702 	} else {
703 		info->rtc_irq =  parent_i2c->irq;
704 	}
705 
706 	info->regmap = dev_get_regmap(parent, NULL);
707 	if (!info->regmap)
708 		return dev_err_probe(info->dev, -ENODEV,
709 				     "Failed to get rtc regmap\n");
710 
711 	if (info->drv_data->rtc_i2c_addr == MAX77686_INVALID_I2C_ADDR) {
712 		info->rtc_regmap = info->regmap;
713 		goto add_rtc_irq;
714 	}
715 
716 	client = devm_i2c_new_dummy_device(info->dev, parent_i2c->adapter,
717 					   info->drv_data->rtc_i2c_addr);
718 	if (IS_ERR(client))
719 		return dev_err_probe(info->dev, PTR_ERR(client),
720 				     "Failed to allocate I2C device for RTC\n");
721 
722 	info->rtc_regmap = devm_regmap_init_i2c(client,
723 						info->drv_data->regmap_config);
724 	if (IS_ERR(info->rtc_regmap))
725 		return dev_err_probe(info->dev, PTR_ERR(info->rtc_regmap),
726 				     "Failed to allocate RTC regmap\n");
727 
728 add_rtc_irq:
729 	ret = regmap_add_irq_chip(info->rtc_regmap, info->rtc_irq,
730 				  IRQF_ONESHOT | IRQF_SHARED,
731 				  0, info->drv_data->rtc_irq_chip,
732 				  &info->rtc_irq_data);
733 	if (ret < 0)
734 		return dev_err_probe(info->dev, ret,
735 				     "Failed to add RTC irq chip\n");
736 
737 	return 0;
738 }
739 
740 static int max77686_rtc_probe(struct platform_device *pdev)
741 {
742 	struct max77686_rtc_info *info;
743 	const struct platform_device_id *id = platform_get_device_id(pdev);
744 	int ret;
745 
746 	info = devm_kzalloc(&pdev->dev, sizeof(struct max77686_rtc_info),
747 			    GFP_KERNEL);
748 	if (!info)
749 		return -ENOMEM;
750 
751 	mutex_init(&info->lock);
752 	info->dev = &pdev->dev;
753 	info->drv_data = (const struct max77686_rtc_driver_data *)
754 		id->driver_data;
755 
756 	ret = max77686_init_rtc_regmap(info);
757 	if (ret < 0)
758 		return ret;
759 
760 	platform_set_drvdata(pdev, info);
761 
762 	ret = max77686_rtc_init_reg(info);
763 	if (ret < 0) {
764 		dev_err(&pdev->dev, "Failed to initialize RTC reg:%d\n", ret);
765 		goto err_rtc;
766 	}
767 
768 	device_init_wakeup(&pdev->dev, true);
769 
770 	info->rtc_dev = devm_rtc_device_register(&pdev->dev, id->name,
771 					&max77686_rtc_ops, THIS_MODULE);
772 
773 	if (IS_ERR(info->rtc_dev)) {
774 		ret = PTR_ERR(info->rtc_dev);
775 		dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
776 		if (ret == 0)
777 			ret = -EINVAL;
778 		goto err_rtc;
779 	}
780 
781 	info->virq = regmap_irq_get_virq(info->rtc_irq_data,
782 					 MAX77686_RTCIRQ_RTCA1);
783 	if (info->virq <= 0) {
784 		ret = -ENXIO;
785 		goto err_rtc;
786 	}
787 
788 	ret = request_threaded_irq(info->virq, NULL, max77686_rtc_alarm_irq, 0,
789 				   "rtc-alarm1", info);
790 	if (ret < 0) {
791 		dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
792 			info->virq, ret);
793 		goto err_rtc;
794 	}
795 
796 	return 0;
797 
798 err_rtc:
799 	regmap_del_irq_chip(info->rtc_irq, info->rtc_irq_data);
800 
801 	return ret;
802 }
803 
804 static void max77686_rtc_remove(struct platform_device *pdev)
805 {
806 	struct max77686_rtc_info *info = platform_get_drvdata(pdev);
807 
808 	free_irq(info->virq, info);
809 	regmap_del_irq_chip(info->rtc_irq, info->rtc_irq_data);
810 }
811 
812 #ifdef CONFIG_PM_SLEEP
813 static int max77686_rtc_suspend(struct device *dev)
814 {
815 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
816 	int ret = 0;
817 
818 	if (device_may_wakeup(dev)) {
819 		struct max77686_rtc_info *info = dev_get_drvdata(dev);
820 
821 		ret = enable_irq_wake(info->virq);
822 	}
823 
824 	/*
825 	 * If the main IRQ (not virtual) is the parent IRQ, then it must be
826 	 * disabled during suspend because if it happens while suspended it
827 	 * will be handled before resuming I2C.
828 	 *
829 	 * Since Main IRQ is shared, all its users should disable it to be sure
830 	 * it won't fire while one of them is still suspended.
831 	 */
832 	if (!info->drv_data->rtc_irq_from_platform)
833 		disable_irq(info->rtc_irq);
834 
835 	return ret;
836 }
837 
838 static int max77686_rtc_resume(struct device *dev)
839 {
840 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
841 
842 	if (!info->drv_data->rtc_irq_from_platform)
843 		enable_irq(info->rtc_irq);
844 
845 	if (device_may_wakeup(dev)) {
846 		struct max77686_rtc_info *info = dev_get_drvdata(dev);
847 
848 		return disable_irq_wake(info->virq);
849 	}
850 
851 	return 0;
852 }
853 #endif
854 
855 static SIMPLE_DEV_PM_OPS(max77686_rtc_pm_ops,
856 			 max77686_rtc_suspend, max77686_rtc_resume);
857 
858 static const struct platform_device_id rtc_id[] = {
859 	{ "max77686-rtc", .driver_data = (kernel_ulong_t)&max77686_drv_data, },
860 	{ "max77802-rtc", .driver_data = (kernel_ulong_t)&max77802_drv_data, },
861 	{ "max77620-rtc", .driver_data = (kernel_ulong_t)&max77620_drv_data, },
862 	{ "max77714-rtc", .driver_data = (kernel_ulong_t)&max77714_drv_data, },
863 	{},
864 };
865 MODULE_DEVICE_TABLE(platform, rtc_id);
866 
867 static struct platform_driver max77686_rtc_driver = {
868 	.driver		= {
869 		.name	= "max77686-rtc",
870 		.pm	= &max77686_rtc_pm_ops,
871 	},
872 	.probe		= max77686_rtc_probe,
873 	.remove		= max77686_rtc_remove,
874 	.id_table	= rtc_id,
875 };
876 
877 module_platform_driver(max77686_rtc_driver);
878 
879 MODULE_DESCRIPTION("Maxim MAX77686 RTC driver");
880 MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
881 MODULE_LICENSE("GPL");
882