xref: /linux/drivers/rtc/rtc-max77686.c (revision 37744feebc086908fd89760650f458ab19071750)
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 };
82 
83 struct max77686_rtc_info {
84 	struct device		*dev;
85 	struct i2c_client	*rtc;
86 	struct rtc_device	*rtc_dev;
87 	struct mutex		lock;
88 
89 	struct regmap		*regmap;
90 	struct regmap		*rtc_regmap;
91 
92 	const struct max77686_rtc_driver_data *drv_data;
93 	struct regmap_irq_chip_data *rtc_irq_data;
94 
95 	int rtc_irq;
96 	int virq;
97 	int rtc_24hr_mode;
98 };
99 
100 enum MAX77686_RTC_OP {
101 	MAX77686_RTC_WRITE,
102 	MAX77686_RTC_READ,
103 };
104 
105 /* These are not registers but just offsets that are mapped to addresses */
106 enum max77686_rtc_reg_offset {
107 	REG_RTC_CONTROLM = 0,
108 	REG_RTC_CONTROL,
109 	REG_RTC_UPDATE0,
110 	REG_WTSR_SMPL_CNTL,
111 	REG_RTC_SEC,
112 	REG_RTC_MIN,
113 	REG_RTC_HOUR,
114 	REG_RTC_WEEKDAY,
115 	REG_RTC_MONTH,
116 	REG_RTC_YEAR,
117 	REG_RTC_DATE,
118 	REG_ALARM1_SEC,
119 	REG_ALARM1_MIN,
120 	REG_ALARM1_HOUR,
121 	REG_ALARM1_WEEKDAY,
122 	REG_ALARM1_MONTH,
123 	REG_ALARM1_YEAR,
124 	REG_ALARM1_DATE,
125 	REG_ALARM2_SEC,
126 	REG_ALARM2_MIN,
127 	REG_ALARM2_HOUR,
128 	REG_ALARM2_WEEKDAY,
129 	REG_ALARM2_MONTH,
130 	REG_ALARM2_YEAR,
131 	REG_ALARM2_DATE,
132 	REG_RTC_AE1,
133 	REG_RTC_END,
134 };
135 
136 /* Maps RTC registers offset to the MAX77686 register addresses */
137 static const unsigned int max77686_map[REG_RTC_END] = {
138 	[REG_RTC_CONTROLM]   = MAX77686_RTC_CONTROLM,
139 	[REG_RTC_CONTROL]    = MAX77686_RTC_CONTROL,
140 	[REG_RTC_UPDATE0]    = MAX77686_RTC_UPDATE0,
141 	[REG_WTSR_SMPL_CNTL] = MAX77686_WTSR_SMPL_CNTL,
142 	[REG_RTC_SEC]        = MAX77686_RTC_SEC,
143 	[REG_RTC_MIN]        = MAX77686_RTC_MIN,
144 	[REG_RTC_HOUR]       = MAX77686_RTC_HOUR,
145 	[REG_RTC_WEEKDAY]    = MAX77686_RTC_WEEKDAY,
146 	[REG_RTC_MONTH]      = MAX77686_RTC_MONTH,
147 	[REG_RTC_YEAR]       = MAX77686_RTC_YEAR,
148 	[REG_RTC_DATE]       = MAX77686_RTC_DATE,
149 	[REG_ALARM1_SEC]     = MAX77686_ALARM1_SEC,
150 	[REG_ALARM1_MIN]     = MAX77686_ALARM1_MIN,
151 	[REG_ALARM1_HOUR]    = MAX77686_ALARM1_HOUR,
152 	[REG_ALARM1_WEEKDAY] = MAX77686_ALARM1_WEEKDAY,
153 	[REG_ALARM1_MONTH]   = MAX77686_ALARM1_MONTH,
154 	[REG_ALARM1_YEAR]    = MAX77686_ALARM1_YEAR,
155 	[REG_ALARM1_DATE]    = MAX77686_ALARM1_DATE,
156 	[REG_ALARM2_SEC]     = MAX77686_ALARM2_SEC,
157 	[REG_ALARM2_MIN]     = MAX77686_ALARM2_MIN,
158 	[REG_ALARM2_HOUR]    = MAX77686_ALARM2_HOUR,
159 	[REG_ALARM2_WEEKDAY] = MAX77686_ALARM2_WEEKDAY,
160 	[REG_ALARM2_MONTH]   = MAX77686_ALARM2_MONTH,
161 	[REG_ALARM2_YEAR]    = MAX77686_ALARM2_YEAR,
162 	[REG_ALARM2_DATE]    = MAX77686_ALARM2_DATE,
163 	[REG_RTC_AE1]	     = REG_RTC_NONE,
164 };
165 
166 static const struct regmap_irq max77686_rtc_irqs[] = {
167 	/* RTC interrupts */
168 	REGMAP_IRQ_REG(0, 0, MAX77686_RTCINT_RTC60S_MSK),
169 	REGMAP_IRQ_REG(1, 0, MAX77686_RTCINT_RTCA1_MSK),
170 	REGMAP_IRQ_REG(2, 0, MAX77686_RTCINT_RTCA2_MSK),
171 	REGMAP_IRQ_REG(3, 0, MAX77686_RTCINT_SMPL_MSK),
172 	REGMAP_IRQ_REG(4, 0, MAX77686_RTCINT_RTC1S_MSK),
173 	REGMAP_IRQ_REG(5, 0, MAX77686_RTCINT_WTSR_MSK),
174 };
175 
176 static const struct regmap_irq_chip max77686_rtc_irq_chip = {
177 	.name		= "max77686-rtc",
178 	.status_base	= MAX77686_RTC_INT,
179 	.mask_base	= MAX77686_RTC_INTM,
180 	.num_regs	= 1,
181 	.irqs		= max77686_rtc_irqs,
182 	.num_irqs	= ARRAY_SIZE(max77686_rtc_irqs),
183 };
184 
185 static const struct max77686_rtc_driver_data max77686_drv_data = {
186 	.delay = 16000,
187 	.mask  = 0x7f,
188 	.map   = max77686_map,
189 	.alarm_enable_reg  = false,
190 	.rtc_irq_from_platform = false,
191 	.alarm_pending_status_reg = MAX77686_REG_STATUS2,
192 	.rtc_i2c_addr = MAX77686_I2C_ADDR_RTC,
193 	.rtc_irq_chip = &max77686_rtc_irq_chip,
194 };
195 
196 static const struct max77686_rtc_driver_data max77620_drv_data = {
197 	.delay = 16000,
198 	.mask  = 0x7f,
199 	.map   = max77686_map,
200 	.alarm_enable_reg  = false,
201 	.rtc_irq_from_platform = true,
202 	.alarm_pending_status_reg = MAX77686_INVALID_REG,
203 	.rtc_i2c_addr = MAX77620_I2C_ADDR_RTC,
204 	.rtc_irq_chip = &max77686_rtc_irq_chip,
205 };
206 
207 static const unsigned int max77802_map[REG_RTC_END] = {
208 	[REG_RTC_CONTROLM]   = MAX77802_RTC_CONTROLM,
209 	[REG_RTC_CONTROL]    = MAX77802_RTC_CONTROL,
210 	[REG_RTC_UPDATE0]    = MAX77802_RTC_UPDATE0,
211 	[REG_WTSR_SMPL_CNTL] = MAX77802_WTSR_SMPL_CNTL,
212 	[REG_RTC_SEC]        = MAX77802_RTC_SEC,
213 	[REG_RTC_MIN]        = MAX77802_RTC_MIN,
214 	[REG_RTC_HOUR]       = MAX77802_RTC_HOUR,
215 	[REG_RTC_WEEKDAY]    = MAX77802_RTC_WEEKDAY,
216 	[REG_RTC_MONTH]      = MAX77802_RTC_MONTH,
217 	[REG_RTC_YEAR]       = MAX77802_RTC_YEAR,
218 	[REG_RTC_DATE]       = MAX77802_RTC_DATE,
219 	[REG_ALARM1_SEC]     = MAX77802_ALARM1_SEC,
220 	[REG_ALARM1_MIN]     = MAX77802_ALARM1_MIN,
221 	[REG_ALARM1_HOUR]    = MAX77802_ALARM1_HOUR,
222 	[REG_ALARM1_WEEKDAY] = MAX77802_ALARM1_WEEKDAY,
223 	[REG_ALARM1_MONTH]   = MAX77802_ALARM1_MONTH,
224 	[REG_ALARM1_YEAR]    = MAX77802_ALARM1_YEAR,
225 	[REG_ALARM1_DATE]    = MAX77802_ALARM1_DATE,
226 	[REG_ALARM2_SEC]     = MAX77802_ALARM2_SEC,
227 	[REG_ALARM2_MIN]     = MAX77802_ALARM2_MIN,
228 	[REG_ALARM2_HOUR]    = MAX77802_ALARM2_HOUR,
229 	[REG_ALARM2_WEEKDAY] = MAX77802_ALARM2_WEEKDAY,
230 	[REG_ALARM2_MONTH]   = MAX77802_ALARM2_MONTH,
231 	[REG_ALARM2_YEAR]    = MAX77802_ALARM2_YEAR,
232 	[REG_ALARM2_DATE]    = MAX77802_ALARM2_DATE,
233 	[REG_RTC_AE1]	     = MAX77802_RTC_AE1,
234 };
235 
236 static const struct regmap_irq_chip max77802_rtc_irq_chip = {
237 	.name		= "max77802-rtc",
238 	.status_base	= MAX77802_RTC_INT,
239 	.mask_base	= MAX77802_RTC_INTM,
240 	.num_regs	= 1,
241 	.irqs		= max77686_rtc_irqs, /* same masks as 77686 */
242 	.num_irqs	= ARRAY_SIZE(max77686_rtc_irqs),
243 };
244 
245 static const struct max77686_rtc_driver_data max77802_drv_data = {
246 	.delay = 200,
247 	.mask  = 0xff,
248 	.map   = max77802_map,
249 	.alarm_enable_reg  = true,
250 	.rtc_irq_from_platform = false,
251 	.alarm_pending_status_reg = MAX77686_REG_STATUS2,
252 	.rtc_i2c_addr = MAX77686_INVALID_I2C_ADDR,
253 	.rtc_irq_chip = &max77802_rtc_irq_chip,
254 };
255 
256 static void max77686_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
257 				    struct max77686_rtc_info *info)
258 {
259 	u8 mask = info->drv_data->mask;
260 
261 	tm->tm_sec = data[RTC_SEC] & mask;
262 	tm->tm_min = data[RTC_MIN] & mask;
263 	if (info->rtc_24hr_mode) {
264 		tm->tm_hour = data[RTC_HOUR] & 0x1f;
265 	} else {
266 		tm->tm_hour = data[RTC_HOUR] & 0x0f;
267 		if (data[RTC_HOUR] & HOUR_PM_MASK)
268 			tm->tm_hour += 12;
269 	}
270 
271 	/* Only a single bit is set in data[], so fls() would be equivalent */
272 	tm->tm_wday = ffs(data[RTC_WEEKDAY] & mask) - 1;
273 	tm->tm_mday = data[RTC_DATE] & 0x1f;
274 	tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1;
275 	tm->tm_year = data[RTC_YEAR] & mask;
276 	tm->tm_yday = 0;
277 	tm->tm_isdst = 0;
278 
279 	/*
280 	 * MAX77686 uses 1 bit from sec/min/hour/etc RTC registers and the
281 	 * year values are just 0..99 so add 100 to support up to 2099.
282 	 */
283 	if (!info->drv_data->alarm_enable_reg)
284 		tm->tm_year += 100;
285 }
286 
287 static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data,
288 				   struct max77686_rtc_info *info)
289 {
290 	data[RTC_SEC] = tm->tm_sec;
291 	data[RTC_MIN] = tm->tm_min;
292 	data[RTC_HOUR] = tm->tm_hour;
293 	data[RTC_WEEKDAY] = 1 << tm->tm_wday;
294 	data[RTC_DATE] = tm->tm_mday;
295 	data[RTC_MONTH] = tm->tm_mon + 1;
296 
297 	if (info->drv_data->alarm_enable_reg) {
298 		data[RTC_YEAR] = tm->tm_year;
299 		return 0;
300 	}
301 
302 	data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
303 
304 	if (tm->tm_year < 100) {
305 		dev_err(info->dev, "RTC cannot handle the year %d.\n",
306 			1900 + tm->tm_year);
307 		return -EINVAL;
308 	}
309 
310 	return 0;
311 }
312 
313 static int max77686_rtc_update(struct max77686_rtc_info *info,
314 			       enum MAX77686_RTC_OP op)
315 {
316 	int ret;
317 	unsigned int data;
318 	unsigned long delay = info->drv_data->delay;
319 
320 	if (op == MAX77686_RTC_WRITE)
321 		data = 1 << RTC_UDR_SHIFT;
322 	else
323 		data = 1 << RTC_RBUDR_SHIFT;
324 
325 	ret = regmap_update_bits(info->rtc_regmap,
326 				 info->drv_data->map[REG_RTC_UPDATE0],
327 				 data, data);
328 	if (ret < 0)
329 		dev_err(info->dev, "Fail to write update reg(ret=%d, data=0x%x)\n",
330 			ret, data);
331 	else {
332 		/* Minimum delay required before RTC update. */
333 		usleep_range(delay, delay * 2);
334 	}
335 
336 	return ret;
337 }
338 
339 static int max77686_rtc_read_time(struct device *dev, struct rtc_time *tm)
340 {
341 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
342 	u8 data[RTC_NR_TIME];
343 	int ret;
344 
345 	mutex_lock(&info->lock);
346 
347 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
348 	if (ret < 0)
349 		goto out;
350 
351 	ret = regmap_bulk_read(info->rtc_regmap,
352 			       info->drv_data->map[REG_RTC_SEC],
353 			       data, ARRAY_SIZE(data));
354 	if (ret < 0) {
355 		dev_err(info->dev, "Fail to read time reg(%d)\n", ret);
356 		goto out;
357 	}
358 
359 	max77686_rtc_data_to_tm(data, tm, info);
360 
361 out:
362 	mutex_unlock(&info->lock);
363 	return ret;
364 }
365 
366 static int max77686_rtc_set_time(struct device *dev, struct rtc_time *tm)
367 {
368 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
369 	u8 data[RTC_NR_TIME];
370 	int ret;
371 
372 	ret = max77686_rtc_tm_to_data(tm, data, info);
373 	if (ret < 0)
374 		return ret;
375 
376 	mutex_lock(&info->lock);
377 
378 	ret = regmap_bulk_write(info->rtc_regmap,
379 				info->drv_data->map[REG_RTC_SEC],
380 				data, ARRAY_SIZE(data));
381 	if (ret < 0) {
382 		dev_err(info->dev, "Fail to write time reg(%d)\n", ret);
383 		goto out;
384 	}
385 
386 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
387 
388 out:
389 	mutex_unlock(&info->lock);
390 	return ret;
391 }
392 
393 static int max77686_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
394 {
395 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
396 	u8 data[RTC_NR_TIME];
397 	unsigned int val;
398 	const unsigned int *map = info->drv_data->map;
399 	int i, ret;
400 
401 	mutex_lock(&info->lock);
402 
403 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
404 	if (ret < 0)
405 		goto out;
406 
407 	ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
408 			       data, ARRAY_SIZE(data));
409 	if (ret < 0) {
410 		dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
411 		goto out;
412 	}
413 
414 	max77686_rtc_data_to_tm(data, &alrm->time, info);
415 
416 	alrm->enabled = 0;
417 
418 	if (info->drv_data->alarm_enable_reg) {
419 		if (map[REG_RTC_AE1] == REG_RTC_NONE) {
420 			ret = -EINVAL;
421 			dev_err(info->dev,
422 				"alarm enable register not set(%d)\n", ret);
423 			goto out;
424 		}
425 
426 		ret = regmap_read(info->rtc_regmap, map[REG_RTC_AE1], &val);
427 		if (ret < 0) {
428 			dev_err(info->dev,
429 				"fail to read alarm enable(%d)\n", ret);
430 			goto out;
431 		}
432 
433 		if (val)
434 			alrm->enabled = 1;
435 	} else {
436 		for (i = 0; i < ARRAY_SIZE(data); i++) {
437 			if (data[i] & ALARM_ENABLE_MASK) {
438 				alrm->enabled = 1;
439 				break;
440 			}
441 		}
442 	}
443 
444 	alrm->pending = 0;
445 
446 	if (info->drv_data->alarm_pending_status_reg == MAX77686_INVALID_REG)
447 		goto out;
448 
449 	ret = regmap_read(info->regmap,
450 			  info->drv_data->alarm_pending_status_reg, &val);
451 	if (ret < 0) {
452 		dev_err(info->dev,
453 			"Fail to read alarm pending status reg(%d)\n", ret);
454 		goto out;
455 	}
456 
457 	if (val & (1 << 4)) /* RTCA1 */
458 		alrm->pending = 1;
459 
460 out:
461 	mutex_unlock(&info->lock);
462 	return ret;
463 }
464 
465 static int max77686_rtc_stop_alarm(struct max77686_rtc_info *info)
466 {
467 	u8 data[RTC_NR_TIME];
468 	int ret, i;
469 	struct rtc_time tm;
470 	const unsigned int *map = info->drv_data->map;
471 
472 	if (!mutex_is_locked(&info->lock))
473 		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
474 
475 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
476 	if (ret < 0)
477 		goto out;
478 
479 	if (info->drv_data->alarm_enable_reg) {
480 		if (map[REG_RTC_AE1] == REG_RTC_NONE) {
481 			ret = -EINVAL;
482 			dev_err(info->dev,
483 				"alarm enable register not set(%d)\n", ret);
484 			goto out;
485 		}
486 
487 		ret = regmap_write(info->rtc_regmap, map[REG_RTC_AE1], 0);
488 	} else {
489 		ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
490 				       data, ARRAY_SIZE(data));
491 		if (ret < 0) {
492 			dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
493 			goto out;
494 		}
495 
496 		max77686_rtc_data_to_tm(data, &tm, info);
497 
498 		for (i = 0; i < ARRAY_SIZE(data); i++)
499 			data[i] &= ~ALARM_ENABLE_MASK;
500 
501 		ret = regmap_bulk_write(info->rtc_regmap, map[REG_ALARM1_SEC],
502 					data, ARRAY_SIZE(data));
503 	}
504 
505 	if (ret < 0) {
506 		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
507 		goto out;
508 	}
509 
510 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
511 out:
512 	return ret;
513 }
514 
515 static int max77686_rtc_start_alarm(struct max77686_rtc_info *info)
516 {
517 	u8 data[RTC_NR_TIME];
518 	int ret;
519 	struct rtc_time tm;
520 	const unsigned int *map = info->drv_data->map;
521 
522 	if (!mutex_is_locked(&info->lock))
523 		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
524 
525 	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
526 	if (ret < 0)
527 		goto out;
528 
529 	if (info->drv_data->alarm_enable_reg) {
530 		ret = regmap_write(info->rtc_regmap, map[REG_RTC_AE1],
531 				   MAX77802_ALARM_ENABLE_VALUE);
532 	} else {
533 		ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
534 				       data, ARRAY_SIZE(data));
535 		if (ret < 0) {
536 			dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
537 			goto out;
538 		}
539 
540 		max77686_rtc_data_to_tm(data, &tm, info);
541 
542 		data[RTC_SEC] |= (1 << ALARM_ENABLE_SHIFT);
543 		data[RTC_MIN] |= (1 << ALARM_ENABLE_SHIFT);
544 		data[RTC_HOUR] |= (1 << ALARM_ENABLE_SHIFT);
545 		data[RTC_WEEKDAY] &= ~ALARM_ENABLE_MASK;
546 		if (data[RTC_MONTH] & 0xf)
547 			data[RTC_MONTH] |= (1 << ALARM_ENABLE_SHIFT);
548 		if (data[RTC_YEAR] & info->drv_data->mask)
549 			data[RTC_YEAR] |= (1 << ALARM_ENABLE_SHIFT);
550 		if (data[RTC_DATE] & 0x1f)
551 			data[RTC_DATE] |= (1 << ALARM_ENABLE_SHIFT);
552 
553 		ret = regmap_bulk_write(info->rtc_regmap, map[REG_ALARM1_SEC],
554 					data, ARRAY_SIZE(data));
555 	}
556 
557 	if (ret < 0) {
558 		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
559 		goto out;
560 	}
561 
562 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
563 out:
564 	return ret;
565 }
566 
567 static int max77686_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
568 {
569 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
570 	u8 data[RTC_NR_TIME];
571 	int ret;
572 
573 	ret = max77686_rtc_tm_to_data(&alrm->time, data, info);
574 	if (ret < 0)
575 		return ret;
576 
577 	mutex_lock(&info->lock);
578 
579 	ret = max77686_rtc_stop_alarm(info);
580 	if (ret < 0)
581 		goto out;
582 
583 	ret = regmap_bulk_write(info->rtc_regmap,
584 				info->drv_data->map[REG_ALARM1_SEC],
585 				data, ARRAY_SIZE(data));
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 	if (ret < 0)
594 		goto out;
595 
596 	if (alrm->enabled)
597 		ret = max77686_rtc_start_alarm(info);
598 out:
599 	mutex_unlock(&info->lock);
600 	return ret;
601 }
602 
603 static int max77686_rtc_alarm_irq_enable(struct device *dev,
604 					 unsigned int enabled)
605 {
606 	struct max77686_rtc_info *info = dev_get_drvdata(dev);
607 	int ret;
608 
609 	mutex_lock(&info->lock);
610 	if (enabled)
611 		ret = max77686_rtc_start_alarm(info);
612 	else
613 		ret = max77686_rtc_stop_alarm(info);
614 	mutex_unlock(&info->lock);
615 
616 	return ret;
617 }
618 
619 static irqreturn_t max77686_rtc_alarm_irq(int irq, void *data)
620 {
621 	struct max77686_rtc_info *info = data;
622 
623 	dev_dbg(info->dev, "RTC alarm IRQ: %d\n", irq);
624 
625 	rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
626 
627 	return IRQ_HANDLED;
628 }
629 
630 static const struct rtc_class_ops max77686_rtc_ops = {
631 	.read_time = max77686_rtc_read_time,
632 	.set_time = max77686_rtc_set_time,
633 	.read_alarm = max77686_rtc_read_alarm,
634 	.set_alarm = max77686_rtc_set_alarm,
635 	.alarm_irq_enable = max77686_rtc_alarm_irq_enable,
636 };
637 
638 static int max77686_rtc_init_reg(struct max77686_rtc_info *info)
639 {
640 	u8 data[2];
641 	int ret;
642 
643 	/* Set RTC control register : Binary mode, 24hour mdoe */
644 	data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
645 	data[1] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
646 
647 	info->rtc_24hr_mode = 1;
648 
649 	ret = regmap_bulk_write(info->rtc_regmap,
650 				info->drv_data->map[REG_RTC_CONTROLM],
651 				data, ARRAY_SIZE(data));
652 	if (ret < 0) {
653 		dev_err(info->dev, "Fail to write controlm reg(%d)\n", ret);
654 		return ret;
655 	}
656 
657 	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
658 	return ret;
659 }
660 
661 static const struct regmap_config max77686_rtc_regmap_config = {
662 	.reg_bits = 8,
663 	.val_bits = 8,
664 };
665 
666 static int max77686_init_rtc_regmap(struct max77686_rtc_info *info)
667 {
668 	struct device *parent = info->dev->parent;
669 	struct i2c_client *parent_i2c = to_i2c_client(parent);
670 	int ret;
671 
672 	if (info->drv_data->rtc_irq_from_platform) {
673 		struct platform_device *pdev = to_platform_device(info->dev);
674 
675 		info->rtc_irq = platform_get_irq(pdev, 0);
676 		if (info->rtc_irq < 0)
677 			return info->rtc_irq;
678 	} else {
679 		info->rtc_irq =  parent_i2c->irq;
680 	}
681 
682 	info->regmap = dev_get_regmap(parent, NULL);
683 	if (!info->regmap) {
684 		dev_err(info->dev, "Failed to get rtc regmap\n");
685 		return -ENODEV;
686 	}
687 
688 	if (info->drv_data->rtc_i2c_addr == MAX77686_INVALID_I2C_ADDR) {
689 		info->rtc_regmap = info->regmap;
690 		goto add_rtc_irq;
691 	}
692 
693 	info->rtc = devm_i2c_new_dummy_device(info->dev, parent_i2c->adapter,
694 					      info->drv_data->rtc_i2c_addr);
695 	if (IS_ERR(info->rtc)) {
696 		dev_err(info->dev, "Failed to allocate I2C device for RTC\n");
697 		return PTR_ERR(info->rtc);
698 	}
699 
700 	info->rtc_regmap = devm_regmap_init_i2c(info->rtc,
701 						&max77686_rtc_regmap_config);
702 	if (IS_ERR(info->rtc_regmap)) {
703 		ret = PTR_ERR(info->rtc_regmap);
704 		dev_err(info->dev, "Failed to allocate RTC regmap: %d\n", ret);
705 		return ret;
706 	}
707 
708 add_rtc_irq:
709 	ret = regmap_add_irq_chip(info->rtc_regmap, info->rtc_irq,
710 				  IRQF_TRIGGER_FALLING | IRQF_ONESHOT |
711 				  IRQF_SHARED, 0, info->drv_data->rtc_irq_chip,
712 				  &info->rtc_irq_data);
713 	if (ret < 0) {
714 		dev_err(info->dev, "Failed to add RTC irq chip: %d\n", ret);
715 		return ret;
716 	}
717 
718 	return 0;
719 }
720 
721 static int max77686_rtc_probe(struct platform_device *pdev)
722 {
723 	struct max77686_rtc_info *info;
724 	const struct platform_device_id *id = platform_get_device_id(pdev);
725 	int ret;
726 
727 	info = devm_kzalloc(&pdev->dev, sizeof(struct max77686_rtc_info),
728 			    GFP_KERNEL);
729 	if (!info)
730 		return -ENOMEM;
731 
732 	mutex_init(&info->lock);
733 	info->dev = &pdev->dev;
734 	info->drv_data = (const struct max77686_rtc_driver_data *)
735 		id->driver_data;
736 
737 	ret = max77686_init_rtc_regmap(info);
738 	if (ret < 0)
739 		return ret;
740 
741 	platform_set_drvdata(pdev, info);
742 
743 	ret = max77686_rtc_init_reg(info);
744 	if (ret < 0) {
745 		dev_err(&pdev->dev, "Failed to initialize RTC reg:%d\n", ret);
746 		goto err_rtc;
747 	}
748 
749 	device_init_wakeup(&pdev->dev, 1);
750 
751 	info->rtc_dev = devm_rtc_device_register(&pdev->dev, id->name,
752 					&max77686_rtc_ops, THIS_MODULE);
753 
754 	if (IS_ERR(info->rtc_dev)) {
755 		ret = PTR_ERR(info->rtc_dev);
756 		dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
757 		if (ret == 0)
758 			ret = -EINVAL;
759 		goto err_rtc;
760 	}
761 
762 	info->virq = regmap_irq_get_virq(info->rtc_irq_data,
763 					 MAX77686_RTCIRQ_RTCA1);
764 	if (info->virq <= 0) {
765 		ret = -ENXIO;
766 		goto err_rtc;
767 	}
768 
769 	ret = request_threaded_irq(info->virq, NULL, max77686_rtc_alarm_irq, 0,
770 				   "rtc-alarm1", info);
771 	if (ret < 0) {
772 		dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
773 			info->virq, ret);
774 		goto err_rtc;
775 	}
776 
777 	return 0;
778 
779 err_rtc:
780 	regmap_del_irq_chip(info->rtc_irq, info->rtc_irq_data);
781 
782 	return ret;
783 }
784 
785 static int max77686_rtc_remove(struct platform_device *pdev)
786 {
787 	struct max77686_rtc_info *info = platform_get_drvdata(pdev);
788 
789 	free_irq(info->virq, info);
790 	regmap_del_irq_chip(info->rtc_irq, info->rtc_irq_data);
791 
792 	return 0;
793 }
794 
795 #ifdef CONFIG_PM_SLEEP
796 static int max77686_rtc_suspend(struct device *dev)
797 {
798 	if (device_may_wakeup(dev)) {
799 		struct max77686_rtc_info *info = dev_get_drvdata(dev);
800 
801 		return enable_irq_wake(info->virq);
802 	}
803 
804 	return 0;
805 }
806 
807 static int max77686_rtc_resume(struct device *dev)
808 {
809 	if (device_may_wakeup(dev)) {
810 		struct max77686_rtc_info *info = dev_get_drvdata(dev);
811 
812 		return disable_irq_wake(info->virq);
813 	}
814 
815 	return 0;
816 }
817 #endif
818 
819 static SIMPLE_DEV_PM_OPS(max77686_rtc_pm_ops,
820 			 max77686_rtc_suspend, max77686_rtc_resume);
821 
822 static const struct platform_device_id rtc_id[] = {
823 	{ "max77686-rtc", .driver_data = (kernel_ulong_t)&max77686_drv_data, },
824 	{ "max77802-rtc", .driver_data = (kernel_ulong_t)&max77802_drv_data, },
825 	{ "max77620-rtc", .driver_data = (kernel_ulong_t)&max77620_drv_data, },
826 	{},
827 };
828 MODULE_DEVICE_TABLE(platform, rtc_id);
829 
830 static struct platform_driver max77686_rtc_driver = {
831 	.driver		= {
832 		.name	= "max77686-rtc",
833 		.pm	= &max77686_rtc_pm_ops,
834 	},
835 	.probe		= max77686_rtc_probe,
836 	.remove		= max77686_rtc_remove,
837 	.id_table	= rtc_id,
838 };
839 
840 module_platform_driver(max77686_rtc_driver);
841 
842 MODULE_DESCRIPTION("Maxim MAX77686 RTC driver");
843 MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
844 MODULE_LICENSE("GPL");
845