xref: /linux/drivers/rtc/rtc-max77686.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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 i2c_client	*rtc;
89 	struct rtc_device	*rtc_dev;
90 	struct mutex		lock;
91 
92 	struct regmap		*regmap;
93 	struct regmap		*rtc_regmap;
94 
95 	const struct max77686_rtc_driver_data *drv_data;
96 	struct regmap_irq_chip_data *rtc_irq_data;
97 
98 	int rtc_irq;
99 	int virq;
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_MONTHDAY,
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_MONTHDAY]   = MAX77686_RTC_MONTHDAY,
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_irq_chip max77714_rtc_irq_chip = {
205 	.name		= "max77714-rtc",
206 	.status_base	= MAX77686_RTC_INT,
207 	.mask_base	= MAX77686_RTC_INTM,
208 	.num_regs	= 1,
209 	.irqs		= max77686_rtc_irqs,
210 	.num_irqs	= ARRAY_SIZE(max77686_rtc_irqs) - 1, /* no WTSR on 77714 */
211 };
212 
213 static const struct max77686_rtc_driver_data max77714_drv_data = {
214 	.delay = 16000,
215 	.mask  = 0x7f,
216 	.map   = max77686_map,
217 	.alarm_enable_reg = false,
218 	.rtc_irq_from_platform = false,
219 	/* On MAX77714 RTCA1 is BIT 1 of RTCINT (0x00). Not supported by this driver. */
220 	.alarm_pending_status_reg = MAX77686_INVALID_REG,
221 	.rtc_i2c_addr = MAX77714_I2C_ADDR_RTC,
222 	.rtc_irq_chip = &max77714_rtc_irq_chip,
223 	.regmap_config = &max77686_rtc_regmap_config,
224 };
225 
226 static const struct regmap_config max77620_rtc_regmap_config = {
227 	.reg_bits = 8,
228 	.val_bits = 8,
229 	.use_single_write = true,
230 };
231 
232 static const struct max77686_rtc_driver_data max77620_drv_data = {
233 	.delay = 16000,
234 	.mask  = 0x7f,
235 	.map   = max77686_map,
236 	.alarm_enable_reg  = false,
237 	.rtc_irq_from_platform = true,
238 	.alarm_pending_status_reg = MAX77686_INVALID_REG,
239 	.rtc_i2c_addr = MAX77620_I2C_ADDR_RTC,
240 	.rtc_irq_chip = &max77686_rtc_irq_chip,
241 	.regmap_config = &max77620_rtc_regmap_config,
242 };
243 
244 static const unsigned int max77802_map[REG_RTC_END] = {
245 	[REG_RTC_CONTROLM]   = MAX77802_RTC_CONTROLM,
246 	[REG_RTC_CONTROL]    = MAX77802_RTC_CONTROL,
247 	[REG_RTC_UPDATE0]    = MAX77802_RTC_UPDATE0,
248 	[REG_WTSR_SMPL_CNTL] = MAX77802_WTSR_SMPL_CNTL,
249 	[REG_RTC_SEC]        = MAX77802_RTC_SEC,
250 	[REG_RTC_MIN]        = MAX77802_RTC_MIN,
251 	[REG_RTC_HOUR]       = MAX77802_RTC_HOUR,
252 	[REG_RTC_WEEKDAY]    = MAX77802_RTC_WEEKDAY,
253 	[REG_RTC_MONTH]      = MAX77802_RTC_MONTH,
254 	[REG_RTC_YEAR]       = MAX77802_RTC_YEAR,
255 	[REG_RTC_MONTHDAY]   = MAX77802_RTC_MONTHDAY,
256 	[REG_ALARM1_SEC]     = MAX77802_ALARM1_SEC,
257 	[REG_ALARM1_MIN]     = MAX77802_ALARM1_MIN,
258 	[REG_ALARM1_HOUR]    = MAX77802_ALARM1_HOUR,
259 	[REG_ALARM1_WEEKDAY] = MAX77802_ALARM1_WEEKDAY,
260 	[REG_ALARM1_MONTH]   = MAX77802_ALARM1_MONTH,
261 	[REG_ALARM1_YEAR]    = MAX77802_ALARM1_YEAR,
262 	[REG_ALARM1_DATE]    = MAX77802_ALARM1_DATE,
263 	[REG_ALARM2_SEC]     = MAX77802_ALARM2_SEC,
264 	[REG_ALARM2_MIN]     = MAX77802_ALARM2_MIN,
265 	[REG_ALARM2_HOUR]    = MAX77802_ALARM2_HOUR,
266 	[REG_ALARM2_WEEKDAY] = MAX77802_ALARM2_WEEKDAY,
267 	[REG_ALARM2_MONTH]   = MAX77802_ALARM2_MONTH,
268 	[REG_ALARM2_YEAR]    = MAX77802_ALARM2_YEAR,
269 	[REG_ALARM2_DATE]    = MAX77802_ALARM2_DATE,
270 	[REG_RTC_AE1]	     = MAX77802_RTC_AE1,
271 };
272 
273 static const struct regmap_irq_chip max77802_rtc_irq_chip = {
274 	.name		= "max77802-rtc",
275 	.status_base	= MAX77802_RTC_INT,
276 	.mask_base	= MAX77802_RTC_INTM,
277 	.num_regs	= 1,
278 	.irqs		= max77686_rtc_irqs, /* same masks as 77686 */
279 	.num_irqs	= ARRAY_SIZE(max77686_rtc_irqs),
280 };
281 
282 static const struct max77686_rtc_driver_data max77802_drv_data = {
283 	.delay = 200,
284 	.mask  = 0xff,
285 	.map   = max77802_map,
286 	.alarm_enable_reg  = true,
287 	.rtc_irq_from_platform = false,
288 	.alarm_pending_status_reg = MAX77686_REG_STATUS2,
289 	.rtc_i2c_addr = MAX77686_INVALID_I2C_ADDR,
290 	.rtc_irq_chip = &max77802_rtc_irq_chip,
291 };
292 
293 static void max77686_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
294 				    struct max77686_rtc_info *info)
295 {
296 	u8 mask = info->drv_data->mask;
297 
298 	tm->tm_sec = data[RTC_SEC] & mask;
299 	tm->tm_min = data[RTC_MIN] & mask;
300 	tm->tm_hour = data[RTC_HOUR] & 0x1f;
301 
302 	/* Only a single bit is set in data[], so fls() would be equivalent */
303 	tm->tm_wday = ffs(data[RTC_WEEKDAY] & mask) - 1;
304 	tm->tm_mday = data[RTC_MONTHDAY] & 0x1f;
305 	tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1;
306 	tm->tm_year = data[RTC_YEAR] & mask;
307 	tm->tm_yday = 0;
308 	tm->tm_isdst = 0;
309 
310 	/*
311 	 * MAX77686 uses 1 bit from sec/min/hour/etc RTC registers and the
312 	 * year values are just 0..99 so add 100 to support up to 2099.
313 	 */
314 	if (!info->drv_data->alarm_enable_reg)
315 		tm->tm_year += 100;
316 }
317 
318 static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data,
319 				   struct max77686_rtc_info *info)
320 {
321 	data[RTC_SEC] = tm->tm_sec;
322 	data[RTC_MIN] = tm->tm_min;
323 	data[RTC_HOUR] = tm->tm_hour;
324 	data[RTC_WEEKDAY] = 1 << tm->tm_wday;
325 	data[RTC_MONTHDAY] = tm->tm_mday;
326 	data[RTC_MONTH] = tm->tm_mon + 1;
327 
328 	if (info->drv_data->alarm_enable_reg) {
329 		data[RTC_YEAR] = tm->tm_year;
330 		return 0;
331 	}
332 
333 	data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
334 
335 	if (tm->tm_year < 100) {
336 		dev_err(info->dev, "RTC cannot handle the year %d.\n",
337 			1900 + tm->tm_year);
338 		return -EINVAL;
339 	}
340 
341 	return 0;
342 }
343 
344 static int max77686_rtc_update(struct max77686_rtc_info *info,
345 			       enum MAX77686_RTC_OP op)
346 {
347 	int ret;
348 	unsigned int data;
349 	unsigned long delay = info->drv_data->delay;
350 
351 	if (op == MAX77686_RTC_WRITE)
352 		data = 1 << RTC_UDR_SHIFT;
353 	else
354 		data = 1 << RTC_RBUDR_SHIFT;
355 
356 	ret = regmap_update_bits(info->rtc_regmap,
357 				 info->drv_data->map[REG_RTC_UPDATE0],
358 				 data, data);
359 	if (ret < 0)
360 		dev_err(info->dev, "Fail to write update reg(ret=%d, data=0x%x)\n",
361 			ret, data);
362 	else {
363 		/* Minimum delay required before RTC update. */
364 		usleep_range(delay, delay * 2);
365 	}
366 
367 	return ret;
368 }
369 
370 static int max77686_rtc_read_time(struct device *dev, struct rtc_time *tm)
371 {
372 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
373 	u8 data[RTC_NR_TIME];
374 	int ret;
375 
376 	mutex_lock(&info->lock);
377 
378 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
379 	if (ret < 0)
380 		goto out;
381 
382 	ret = regmap_bulk_read(info->rtc_regmap,
383 			       info->drv_data->map[REG_RTC_SEC],
384 			       data, ARRAY_SIZE(data));
385 	if (ret < 0) {
386 		dev_err(info->dev, "Fail to read time reg(%d)\n", ret);
387 		goto out;
388 	}
389 
390 	max77686_rtc_data_to_tm(data, tm, info);
391 
392 out:
393 	mutex_unlock(&info->lock);
394 	return ret;
395 }
396 
397 static int max77686_rtc_set_time(struct device *dev, struct rtc_time *tm)
398 {
399 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
400 	u8 data[RTC_NR_TIME];
401 	int ret;
402 
403 	ret = max77686_rtc_tm_to_data(tm, data, info);
404 	if (ret < 0)
405 		return ret;
406 
407 	mutex_lock(&info->lock);
408 
409 	ret = regmap_bulk_write(info->rtc_regmap,
410 				info->drv_data->map[REG_RTC_SEC],
411 				data, ARRAY_SIZE(data));
412 	if (ret < 0) {
413 		dev_err(info->dev, "Fail to write time reg(%d)\n", ret);
414 		goto out;
415 	}
416 
417 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
418 
419 out:
420 	mutex_unlock(&info->lock);
421 	return ret;
422 }
423 
424 static int max77686_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
425 {
426 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
427 	u8 data[RTC_NR_TIME];
428 	unsigned int val;
429 	const unsigned int *map = info->drv_data->map;
430 	int i, ret;
431 
432 	mutex_lock(&info->lock);
433 
434 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
435 	if (ret < 0)
436 		goto out;
437 
438 	ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
439 			       data, ARRAY_SIZE(data));
440 	if (ret < 0) {
441 		dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
442 		goto out;
443 	}
444 
445 	max77686_rtc_data_to_tm(data, &alrm->time, info);
446 
447 	alrm->enabled = 0;
448 
449 	if (info->drv_data->alarm_enable_reg) {
450 		if (map[REG_RTC_AE1] == REG_RTC_NONE) {
451 			ret = -EINVAL;
452 			dev_err(info->dev,
453 				"alarm enable register not set(%d)\n", ret);
454 			goto out;
455 		}
456 
457 		ret = regmap_read(info->rtc_regmap, map[REG_RTC_AE1], &val);
458 		if (ret < 0) {
459 			dev_err(info->dev,
460 				"fail to read alarm enable(%d)\n", ret);
461 			goto out;
462 		}
463 
464 		if (val)
465 			alrm->enabled = 1;
466 	} else {
467 		for (i = 0; i < ARRAY_SIZE(data); i++) {
468 			if (data[i] & ALARM_ENABLE_MASK) {
469 				alrm->enabled = 1;
470 				break;
471 			}
472 		}
473 	}
474 
475 	alrm->pending = 0;
476 
477 	if (info->drv_data->alarm_pending_status_reg == MAX77686_INVALID_REG)
478 		goto out;
479 
480 	ret = regmap_read(info->regmap,
481 			  info->drv_data->alarm_pending_status_reg, &val);
482 	if (ret < 0) {
483 		dev_err(info->dev,
484 			"Fail to read alarm pending status reg(%d)\n", ret);
485 		goto out;
486 	}
487 
488 	if (val & (1 << 4)) /* RTCA1 */
489 		alrm->pending = 1;
490 
491 out:
492 	mutex_unlock(&info->lock);
493 	return ret;
494 }
495 
496 static int max77686_rtc_stop_alarm(struct max77686_rtc_info *info)
497 {
498 	u8 data[RTC_NR_TIME];
499 	int ret, i;
500 	struct rtc_time tm;
501 	const unsigned int *map = info->drv_data->map;
502 
503 	if (!mutex_is_locked(&info->lock))
504 		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
505 
506 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
507 	if (ret < 0)
508 		goto out;
509 
510 	if (info->drv_data->alarm_enable_reg) {
511 		if (map[REG_RTC_AE1] == REG_RTC_NONE) {
512 			ret = -EINVAL;
513 			dev_err(info->dev,
514 				"alarm enable register not set(%d)\n", ret);
515 			goto out;
516 		}
517 
518 		ret = regmap_write(info->rtc_regmap, map[REG_RTC_AE1], 0);
519 	} else {
520 		ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
521 				       data, ARRAY_SIZE(data));
522 		if (ret < 0) {
523 			dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
524 			goto out;
525 		}
526 
527 		max77686_rtc_data_to_tm(data, &tm, info);
528 
529 		for (i = 0; i < ARRAY_SIZE(data); i++)
530 			data[i] &= ~ALARM_ENABLE_MASK;
531 
532 		ret = regmap_bulk_write(info->rtc_regmap, map[REG_ALARM1_SEC],
533 					data, ARRAY_SIZE(data));
534 	}
535 
536 	if (ret < 0) {
537 		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
538 		goto out;
539 	}
540 
541 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
542 out:
543 	return ret;
544 }
545 
546 static int max77686_rtc_start_alarm(struct max77686_rtc_info *info)
547 {
548 	u8 data[RTC_NR_TIME];
549 	int ret;
550 	struct rtc_time tm;
551 	const unsigned int *map = info->drv_data->map;
552 
553 	if (!mutex_is_locked(&info->lock))
554 		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
555 
556 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
557 	if (ret < 0)
558 		goto out;
559 
560 	if (info->drv_data->alarm_enable_reg) {
561 		ret = regmap_write(info->rtc_regmap, map[REG_RTC_AE1],
562 				   MAX77802_ALARM_ENABLE_VALUE);
563 	} else {
564 		ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
565 				       data, ARRAY_SIZE(data));
566 		if (ret < 0) {
567 			dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
568 			goto out;
569 		}
570 
571 		max77686_rtc_data_to_tm(data, &tm, info);
572 
573 		data[RTC_SEC] |= (1 << ALARM_ENABLE_SHIFT);
574 		data[RTC_MIN] |= (1 << ALARM_ENABLE_SHIFT);
575 		data[RTC_HOUR] |= (1 << ALARM_ENABLE_SHIFT);
576 		data[RTC_WEEKDAY] &= ~ALARM_ENABLE_MASK;
577 		if (data[RTC_MONTH] & 0xf)
578 			data[RTC_MONTH] |= (1 << ALARM_ENABLE_SHIFT);
579 		if (data[RTC_YEAR] & info->drv_data->mask)
580 			data[RTC_YEAR] |= (1 << ALARM_ENABLE_SHIFT);
581 		if (data[RTC_MONTHDAY] & 0x1f)
582 			data[RTC_MONTHDAY] |= (1 << ALARM_ENABLE_SHIFT);
583 
584 		ret = regmap_bulk_write(info->rtc_regmap, map[REG_ALARM1_SEC],
585 					data, ARRAY_SIZE(data));
586 	}
587 
588 	if (ret < 0) {
589 		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
590 		goto out;
591 	}
592 
593 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
594 out:
595 	return ret;
596 }
597 
598 static int max77686_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
599 {
600 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
601 	u8 data[RTC_NR_TIME];
602 	int ret;
603 
604 	ret = max77686_rtc_tm_to_data(&alrm->time, data, info);
605 	if (ret < 0)
606 		return ret;
607 
608 	mutex_lock(&info->lock);
609 
610 	ret = max77686_rtc_stop_alarm(info);
611 	if (ret < 0)
612 		goto out;
613 
614 	ret = regmap_bulk_write(info->rtc_regmap,
615 				info->drv_data->map[REG_ALARM1_SEC],
616 				data, ARRAY_SIZE(data));
617 
618 	if (ret < 0) {
619 		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
620 		goto out;
621 	}
622 
623 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
624 	if (ret < 0)
625 		goto out;
626 
627 	if (alrm->enabled)
628 		ret = max77686_rtc_start_alarm(info);
629 out:
630 	mutex_unlock(&info->lock);
631 	return ret;
632 }
633 
634 static int max77686_rtc_alarm_irq_enable(struct device *dev,
635 					 unsigned int enabled)
636 {
637 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
638 	int ret;
639 
640 	mutex_lock(&info->lock);
641 	if (enabled)
642 		ret = max77686_rtc_start_alarm(info);
643 	else
644 		ret = max77686_rtc_stop_alarm(info);
645 	mutex_unlock(&info->lock);
646 
647 	return ret;
648 }
649 
650 static irqreturn_t max77686_rtc_alarm_irq(int irq, void *data)
651 {
652 	struct max77686_rtc_info *info = data;
653 
654 	dev_dbg(info->dev, "RTC alarm IRQ: %d\n", irq);
655 
656 	rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
657 
658 	return IRQ_HANDLED;
659 }
660 
661 static const struct rtc_class_ops max77686_rtc_ops = {
662 	.read_time = max77686_rtc_read_time,
663 	.set_time = max77686_rtc_set_time,
664 	.read_alarm = max77686_rtc_read_alarm,
665 	.set_alarm = max77686_rtc_set_alarm,
666 	.alarm_irq_enable = max77686_rtc_alarm_irq_enable,
667 };
668 
669 static int max77686_rtc_init_reg(struct max77686_rtc_info *info)
670 {
671 	u8 data[2];
672 	int ret;
673 
674 	/* Set RTC control register : Binary mode, 24hour mdoe */
675 	data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
676 	data[1] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
677 
678 	ret = regmap_bulk_write(info->rtc_regmap,
679 				info->drv_data->map[REG_RTC_CONTROLM],
680 				data, ARRAY_SIZE(data));
681 	if (ret < 0) {
682 		dev_err(info->dev, "Fail to write controlm reg(%d)\n", ret);
683 		return ret;
684 	}
685 
686 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
687 	return ret;
688 }
689 
690 static int max77686_init_rtc_regmap(struct max77686_rtc_info *info)
691 {
692 	struct device *parent = info->dev->parent;
693 	struct i2c_client *parent_i2c = to_i2c_client(parent);
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 		dev_err(info->dev, "Failed to get rtc regmap\n");
709 		return -ENODEV;
710 	}
711 
712 	if (info->drv_data->rtc_i2c_addr == MAX77686_INVALID_I2C_ADDR) {
713 		info->rtc_regmap = info->regmap;
714 		goto add_rtc_irq;
715 	}
716 
717 	info->rtc = devm_i2c_new_dummy_device(info->dev, parent_i2c->adapter,
718 					      info->drv_data->rtc_i2c_addr);
719 	if (IS_ERR(info->rtc)) {
720 		dev_err(info->dev, "Failed to allocate I2C device for RTC\n");
721 		return PTR_ERR(info->rtc);
722 	}
723 
724 	info->rtc_regmap = devm_regmap_init_i2c(info->rtc,
725 						info->drv_data->regmap_config);
726 	if (IS_ERR(info->rtc_regmap)) {
727 		ret = PTR_ERR(info->rtc_regmap);
728 		dev_err(info->dev, "Failed to allocate RTC regmap: %d\n", ret);
729 		return ret;
730 	}
731 
732 add_rtc_irq:
733 	ret = regmap_add_irq_chip(info->rtc_regmap, info->rtc_irq,
734 				  IRQF_ONESHOT | IRQF_SHARED,
735 				  0, info->drv_data->rtc_irq_chip,
736 				  &info->rtc_irq_data);
737 	if (ret < 0) {
738 		dev_err(info->dev, "Failed to add RTC irq chip: %d\n", ret);
739 		return ret;
740 	}
741 
742 	return 0;
743 }
744 
745 static int max77686_rtc_probe(struct platform_device *pdev)
746 {
747 	struct max77686_rtc_info *info;
748 	const struct platform_device_id *id = platform_get_device_id(pdev);
749 	int ret;
750 
751 	info = devm_kzalloc(&pdev->dev, sizeof(struct max77686_rtc_info),
752 			    GFP_KERNEL);
753 	if (!info)
754 		return -ENOMEM;
755 
756 	mutex_init(&info->lock);
757 	info->dev = &pdev->dev;
758 	info->drv_data = (const struct max77686_rtc_driver_data *)
759 		id->driver_data;
760 
761 	ret = max77686_init_rtc_regmap(info);
762 	if (ret < 0)
763 		return ret;
764 
765 	platform_set_drvdata(pdev, info);
766 
767 	ret = max77686_rtc_init_reg(info);
768 	if (ret < 0) {
769 		dev_err(&pdev->dev, "Failed to initialize RTC reg:%d\n", ret);
770 		goto err_rtc;
771 	}
772 
773 	device_init_wakeup(&pdev->dev, 1);
774 
775 	info->rtc_dev = devm_rtc_device_register(&pdev->dev, id->name,
776 					&max77686_rtc_ops, THIS_MODULE);
777 
778 	if (IS_ERR(info->rtc_dev)) {
779 		ret = PTR_ERR(info->rtc_dev);
780 		dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
781 		if (ret == 0)
782 			ret = -EINVAL;
783 		goto err_rtc;
784 	}
785 
786 	info->virq = regmap_irq_get_virq(info->rtc_irq_data,
787 					 MAX77686_RTCIRQ_RTCA1);
788 	if (info->virq <= 0) {
789 		ret = -ENXIO;
790 		goto err_rtc;
791 	}
792 
793 	ret = request_threaded_irq(info->virq, NULL, max77686_rtc_alarm_irq, 0,
794 				   "rtc-alarm1", info);
795 	if (ret < 0) {
796 		dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
797 			info->virq, ret);
798 		goto err_rtc;
799 	}
800 
801 	return 0;
802 
803 err_rtc:
804 	regmap_del_irq_chip(info->rtc_irq, info->rtc_irq_data);
805 
806 	return ret;
807 }
808 
809 static void max77686_rtc_remove(struct platform_device *pdev)
810 {
811 	struct max77686_rtc_info *info = platform_get_drvdata(pdev);
812 
813 	free_irq(info->virq, info);
814 	regmap_del_irq_chip(info->rtc_irq, info->rtc_irq_data);
815 }
816 
817 #ifdef CONFIG_PM_SLEEP
818 static int max77686_rtc_suspend(struct device *dev)
819 {
820 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
821 	int ret = 0;
822 
823 	if (device_may_wakeup(dev)) {
824 		struct max77686_rtc_info *info = dev_get_drvdata(dev);
825 
826 		ret = enable_irq_wake(info->virq);
827 	}
828 
829 	/*
830 	 * If the main IRQ (not virtual) is the parent IRQ, then it must be
831 	 * disabled during suspend because if it happens while suspended it
832 	 * will be handled before resuming I2C.
833 	 *
834 	 * Since Main IRQ is shared, all its users should disable it to be sure
835 	 * it won't fire while one of them is still suspended.
836 	 */
837 	if (!info->drv_data->rtc_irq_from_platform)
838 		disable_irq(info->rtc_irq);
839 
840 	return ret;
841 }
842 
843 static int max77686_rtc_resume(struct device *dev)
844 {
845 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
846 
847 	if (!info->drv_data->rtc_irq_from_platform)
848 		enable_irq(info->rtc_irq);
849 
850 	if (device_may_wakeup(dev)) {
851 		struct max77686_rtc_info *info = dev_get_drvdata(dev);
852 
853 		return disable_irq_wake(info->virq);
854 	}
855 
856 	return 0;
857 }
858 #endif
859 
860 static SIMPLE_DEV_PM_OPS(max77686_rtc_pm_ops,
861 			 max77686_rtc_suspend, max77686_rtc_resume);
862 
863 static const struct platform_device_id rtc_id[] = {
864 	{ "max77686-rtc", .driver_data = (kernel_ulong_t)&max77686_drv_data, },
865 	{ "max77802-rtc", .driver_data = (kernel_ulong_t)&max77802_drv_data, },
866 	{ "max77620-rtc", .driver_data = (kernel_ulong_t)&max77620_drv_data, },
867 	{ "max77714-rtc", .driver_data = (kernel_ulong_t)&max77714_drv_data, },
868 	{},
869 };
870 MODULE_DEVICE_TABLE(platform, rtc_id);
871 
872 static struct platform_driver max77686_rtc_driver = {
873 	.driver		= {
874 		.name	= "max77686-rtc",
875 		.pm	= &max77686_rtc_pm_ops,
876 	},
877 	.probe		= max77686_rtc_probe,
878 	.remove		= max77686_rtc_remove,
879 	.id_table	= rtc_id,
880 };
881 
882 module_platform_driver(max77686_rtc_driver);
883 
884 MODULE_DESCRIPTION("Maxim MAX77686 RTC driver");
885 MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
886 MODULE_LICENSE("GPL");
887