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v6.8
  1// SPDX-License-Identifier: GPL-2.0+
  2//
  3// RTC driver for Maxim MAX8997
  4//
  5// Copyright (C) 2013 Samsung Electronics Co.Ltd
  6//
  7//  based on rtc-max8998.c
 
 
 
 
 
 
  8
  9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 10
 11#include <linux/slab.h>
 12#include <linux/rtc.h>
 13#include <linux/delay.h>
 14#include <linux/mutex.h>
 15#include <linux/module.h>
 16#include <linux/platform_device.h>
 17#include <linux/mfd/max8997-private.h>
 18#include <linux/irqdomain.h>
 19
 20/* Module parameter for WTSR function control */
 21static int wtsr_en = 1;
 22module_param(wtsr_en, int, 0444);
 23MODULE_PARM_DESC(wtsr_en, "Watchdog Timeout & Software Reset (default=on)");
 24/* Module parameter for SMPL function control */
 25static int smpl_en = 1;
 26module_param(smpl_en, int, 0444);
 27MODULE_PARM_DESC(smpl_en, "Sudden Momentary Power Loss (default=on)");
 28
 29/* RTC Control Register */
 30#define BCD_EN_SHIFT			0
 31#define BCD_EN_MASK			(1 << BCD_EN_SHIFT)
 32#define MODEL24_SHIFT			1
 33#define MODEL24_MASK			(1 << MODEL24_SHIFT)
 34/* RTC Update Register1 */
 35#define RTC_UDR_SHIFT			0
 36#define RTC_UDR_MASK			(1 << RTC_UDR_SHIFT)
 37/* WTSR and SMPL Register */
 38#define WTSRT_SHIFT			0
 39#define SMPLT_SHIFT			2
 40#define WTSR_EN_SHIFT			6
 41#define SMPL_EN_SHIFT			7
 42#define WTSRT_MASK			(3 << WTSRT_SHIFT)
 43#define SMPLT_MASK			(3 << SMPLT_SHIFT)
 44#define WTSR_EN_MASK			(1 << WTSR_EN_SHIFT)
 45#define SMPL_EN_MASK			(1 << SMPL_EN_SHIFT)
 46/* RTC Hour register */
 47#define HOUR_PM_SHIFT			6
 48#define HOUR_PM_MASK			(1 << HOUR_PM_SHIFT)
 49/* RTC Alarm Enable */
 50#define ALARM_ENABLE_SHIFT		7
 51#define ALARM_ENABLE_MASK		(1 << ALARM_ENABLE_SHIFT)
 52
 53enum {
 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
 64struct max8997_rtc_info {
 65	struct device		*dev;
 66	struct max8997_dev	*max8997;
 67	struct i2c_client	*rtc;
 68	struct rtc_device	*rtc_dev;
 69	struct mutex		lock;
 70	int virq;
 71	int rtc_24hr_mode;
 72};
 73
 74static void max8997_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
 75				   int rtc_24hr_mode)
 76{
 77	tm->tm_sec = data[RTC_SEC] & 0x7f;
 78	tm->tm_min = data[RTC_MIN] & 0x7f;
 79	if (rtc_24hr_mode)
 80		tm->tm_hour = data[RTC_HOUR] & 0x1f;
 81	else {
 82		tm->tm_hour = data[RTC_HOUR] & 0x0f;
 83		if (data[RTC_HOUR] & HOUR_PM_MASK)
 84			tm->tm_hour += 12;
 85	}
 86
 87	tm->tm_wday = fls(data[RTC_WEEKDAY] & 0x7f) - 1;
 88	tm->tm_mday = data[RTC_DATE] & 0x1f;
 89	tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1;
 90	tm->tm_year = (data[RTC_YEAR] & 0x7f) + 100;
 91	tm->tm_yday = 0;
 92	tm->tm_isdst = 0;
 93}
 94
 95static int max8997_rtc_tm_to_data(struct rtc_time *tm, u8 *data)
 96{
 97	data[RTC_SEC] = tm->tm_sec;
 98	data[RTC_MIN] = tm->tm_min;
 99	data[RTC_HOUR] = tm->tm_hour;
100	data[RTC_WEEKDAY] = 1 << tm->tm_wday;
101	data[RTC_DATE] = tm->tm_mday;
102	data[RTC_MONTH] = tm->tm_mon + 1;
103	data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
104
105	if (tm->tm_year < 100) {
106		pr_warn("RTC cannot handle the year %d.  Assume it's 2000.\n",
107			1900 + tm->tm_year);
108		return -EINVAL;
109	}
110	return 0;
111}
112
113static inline int max8997_rtc_set_update_reg(struct max8997_rtc_info *info)
114{
115	int ret;
116
117	ret = max8997_write_reg(info->rtc, MAX8997_RTC_UPDATE1,
118						RTC_UDR_MASK);
119	if (ret < 0)
120		dev_err(info->dev, "%s: fail to write update reg(%d)\n",
121				__func__, ret);
122	else {
123		/* Minimum 16ms delay required before RTC update.
124		 * Otherwise, we may read and update based on out-of-date
125		 * value */
126		msleep(20);
127	}
128
129	return ret;
130}
131
132static int max8997_rtc_read_time(struct device *dev, struct rtc_time *tm)
133{
134	struct max8997_rtc_info *info = dev_get_drvdata(dev);
135	u8 data[RTC_NR_TIME];
136	int ret;
137
138	mutex_lock(&info->lock);
139	ret = max8997_bulk_read(info->rtc, MAX8997_RTC_SEC, RTC_NR_TIME, data);
140	mutex_unlock(&info->lock);
141
142	if (ret < 0) {
143		dev_err(info->dev, "%s: fail to read time reg(%d)\n", __func__,
144				ret);
145		return ret;
146	}
147
148	max8997_rtc_data_to_tm(data, tm, info->rtc_24hr_mode);
149
150	return 0;
151}
152
153static int max8997_rtc_set_time(struct device *dev, struct rtc_time *tm)
154{
155	struct max8997_rtc_info *info = dev_get_drvdata(dev);
156	u8 data[RTC_NR_TIME];
157	int ret;
158
159	ret = max8997_rtc_tm_to_data(tm, data);
160	if (ret < 0)
161		return ret;
162
163	mutex_lock(&info->lock);
164
165	ret = max8997_bulk_write(info->rtc, MAX8997_RTC_SEC, RTC_NR_TIME, data);
166	if (ret < 0) {
167		dev_err(info->dev, "%s: fail to write time reg(%d)\n", __func__,
168				ret);
169		goto out;
170	}
171
172	ret = max8997_rtc_set_update_reg(info);
173out:
174	mutex_unlock(&info->lock);
175	return ret;
176}
177
178static int max8997_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
179{
180	struct max8997_rtc_info *info = dev_get_drvdata(dev);
181	u8 data[RTC_NR_TIME];
182	u8 val;
183	int i, ret;
184
185	mutex_lock(&info->lock);
186
187	ret = max8997_bulk_read(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
188			data);
189	if (ret < 0) {
190		dev_err(info->dev, "%s:%d fail to read alarm reg(%d)\n",
191				__func__, __LINE__, ret);
192		goto out;
193	}
194
195	max8997_rtc_data_to_tm(data, &alrm->time, info->rtc_24hr_mode);
196
197	alrm->enabled = 0;
198	for (i = 0; i < RTC_NR_TIME; i++) {
199		if (data[i] & ALARM_ENABLE_MASK) {
200			alrm->enabled = 1;
201			break;
202		}
203	}
204
205	alrm->pending = 0;
206	ret = max8997_read_reg(info->max8997->i2c, MAX8997_REG_STATUS1, &val);
207	if (ret < 0) {
208		dev_err(info->dev, "%s:%d fail to read status1 reg(%d)\n",
209				__func__, __LINE__, ret);
210		goto out;
211	}
212
213	if (val & (1 << 4)) /* RTCA1 */
214		alrm->pending = 1;
215
216out:
217	mutex_unlock(&info->lock);
218	return ret;
219}
220
221static int max8997_rtc_stop_alarm(struct max8997_rtc_info *info)
222{
223	u8 data[RTC_NR_TIME];
224	int ret, i;
225
226	if (!mutex_is_locked(&info->lock))
227		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
228
229	ret = max8997_bulk_read(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
230				data);
231	if (ret < 0) {
232		dev_err(info->dev, "%s: fail to read alarm reg(%d)\n",
233				__func__, ret);
234		goto out;
235	}
236
237	for (i = 0; i < RTC_NR_TIME; i++)
238		data[i] &= ~ALARM_ENABLE_MASK;
239
240	ret = max8997_bulk_write(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
241				 data);
242	if (ret < 0) {
243		dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
244				__func__, ret);
245		goto out;
246	}
247
248	ret = max8997_rtc_set_update_reg(info);
249out:
250	return ret;
251}
252
253static int max8997_rtc_start_alarm(struct max8997_rtc_info *info)
254{
255	u8 data[RTC_NR_TIME];
256	int ret;
257
258	if (!mutex_is_locked(&info->lock))
259		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
260
261	ret = max8997_bulk_read(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
262				data);
263	if (ret < 0) {
264		dev_err(info->dev, "%s: fail to read alarm reg(%d)\n",
265				__func__, ret);
266		goto out;
267	}
268
269	data[RTC_SEC] |= (1 << ALARM_ENABLE_SHIFT);
270	data[RTC_MIN] |= (1 << ALARM_ENABLE_SHIFT);
271	data[RTC_HOUR] |= (1 << ALARM_ENABLE_SHIFT);
272	data[RTC_WEEKDAY] &= ~ALARM_ENABLE_MASK;
273	if (data[RTC_MONTH] & 0xf)
274		data[RTC_MONTH] |= (1 << ALARM_ENABLE_SHIFT);
275	if (data[RTC_YEAR] & 0x7f)
276		data[RTC_YEAR] |= (1 << ALARM_ENABLE_SHIFT);
277	if (data[RTC_DATE] & 0x1f)
278		data[RTC_DATE] |= (1 << ALARM_ENABLE_SHIFT);
279
280	ret = max8997_bulk_write(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
281				 data);
282	if (ret < 0) {
283		dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
284				__func__, ret);
285		goto out;
286	}
287
288	ret = max8997_rtc_set_update_reg(info);
289out:
290	return ret;
291}
292static int max8997_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
293{
294	struct max8997_rtc_info *info = dev_get_drvdata(dev);
295	u8 data[RTC_NR_TIME];
296	int ret;
297
298	ret = max8997_rtc_tm_to_data(&alrm->time, data);
299	if (ret < 0)
300		return ret;
301
302	dev_info(info->dev, "%s: %d-%02d-%02d %02d:%02d:%02d\n", __func__,
303			data[RTC_YEAR] + 2000, data[RTC_MONTH], data[RTC_DATE],
304			data[RTC_HOUR], data[RTC_MIN], data[RTC_SEC]);
305
306	mutex_lock(&info->lock);
307
308	ret = max8997_rtc_stop_alarm(info);
309	if (ret < 0)
310		goto out;
311
312	ret = max8997_bulk_write(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
313				data);
314	if (ret < 0) {
315		dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
316				__func__, ret);
317		goto out;
318	}
319
320	ret = max8997_rtc_set_update_reg(info);
321	if (ret < 0)
322		goto out;
323
324	if (alrm->enabled)
325		ret = max8997_rtc_start_alarm(info);
326out:
327	mutex_unlock(&info->lock);
328	return ret;
329}
330
331static int max8997_rtc_alarm_irq_enable(struct device *dev,
332					unsigned int enabled)
333{
334	struct max8997_rtc_info *info = dev_get_drvdata(dev);
335	int ret;
336
337	mutex_lock(&info->lock);
338	if (enabled)
339		ret = max8997_rtc_start_alarm(info);
340	else
341		ret = max8997_rtc_stop_alarm(info);
342	mutex_unlock(&info->lock);
343
344	return ret;
345}
346
347static irqreturn_t max8997_rtc_alarm_irq(int irq, void *data)
348{
349	struct max8997_rtc_info *info = data;
350
351	dev_info(info->dev, "%s:irq(%d)\n", __func__, irq);
352
353	rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
354
355	return IRQ_HANDLED;
356}
357
358static const struct rtc_class_ops max8997_rtc_ops = {
359	.read_time = max8997_rtc_read_time,
360	.set_time = max8997_rtc_set_time,
361	.read_alarm = max8997_rtc_read_alarm,
362	.set_alarm = max8997_rtc_set_alarm,
363	.alarm_irq_enable = max8997_rtc_alarm_irq_enable,
364};
365
366static void max8997_rtc_enable_wtsr(struct max8997_rtc_info *info, bool enable)
367{
368	int ret;
369	u8 val, mask;
370
371	if (!wtsr_en)
372		return;
373
374	if (enable)
375		val = (1 << WTSR_EN_SHIFT) | (3 << WTSRT_SHIFT);
376	else
377		val = 0;
378
379	mask = WTSR_EN_MASK | WTSRT_MASK;
380
381	dev_info(info->dev, "%s: %s WTSR\n", __func__,
382			enable ? "enable" : "disable");
383
384	ret = max8997_update_reg(info->rtc, MAX8997_RTC_WTSR_SMPL, val, mask);
385	if (ret < 0) {
386		dev_err(info->dev, "%s: fail to update WTSR reg(%d)\n",
387				__func__, ret);
388		return;
389	}
390
391	max8997_rtc_set_update_reg(info);
392}
393
394static void max8997_rtc_enable_smpl(struct max8997_rtc_info *info, bool enable)
395{
396	int ret;
397	u8 val, mask;
398
399	if (!smpl_en)
400		return;
401
402	if (enable)
403		val = (1 << SMPL_EN_SHIFT) | (0 << SMPLT_SHIFT);
404	else
405		val = 0;
406
407	mask = SMPL_EN_MASK | SMPLT_MASK;
408
409	dev_info(info->dev, "%s: %s SMPL\n", __func__,
410			enable ? "enable" : "disable");
411
412	ret = max8997_update_reg(info->rtc, MAX8997_RTC_WTSR_SMPL, val, mask);
413	if (ret < 0) {
414		dev_err(info->dev, "%s: fail to update SMPL reg(%d)\n",
415				__func__, ret);
416		return;
417	}
418
419	max8997_rtc_set_update_reg(info);
420
421	val = 0;
422	max8997_read_reg(info->rtc, MAX8997_RTC_WTSR_SMPL, &val);
423	pr_info("WTSR_SMPL(0x%02x)\n", val);
424}
425
426static int max8997_rtc_init_reg(struct max8997_rtc_info *info)
427{
428	u8 data[2];
429	int ret;
430
431	/* Set RTC control register : Binary mode, 24hour mdoe */
432	data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
433	data[1] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
434
435	info->rtc_24hr_mode = 1;
436
437	ret = max8997_bulk_write(info->rtc, MAX8997_RTC_CTRLMASK, 2, data);
438	if (ret < 0) {
439		dev_err(info->dev, "%s: fail to write controlm reg(%d)\n",
440				__func__, ret);
441		return ret;
442	}
443
444	ret = max8997_rtc_set_update_reg(info);
445	return ret;
446}
447
448static int max8997_rtc_probe(struct platform_device *pdev)
449{
450	struct max8997_dev *max8997 = dev_get_drvdata(pdev->dev.parent);
451	struct max8997_rtc_info *info;
452	int ret, virq;
453
454	info = devm_kzalloc(&pdev->dev, sizeof(struct max8997_rtc_info),
455			GFP_KERNEL);
456	if (!info)
457		return -ENOMEM;
458
459	mutex_init(&info->lock);
460	info->dev = &pdev->dev;
461	info->max8997 = max8997;
462	info->rtc = max8997->rtc;
463
464	platform_set_drvdata(pdev, info);
465
466	ret = max8997_rtc_init_reg(info);
467
468	if (ret < 0) {
469		dev_err(&pdev->dev, "Failed to initialize RTC reg:%d\n", ret);
470		return ret;
471	}
472
473	max8997_rtc_enable_wtsr(info, true);
474	max8997_rtc_enable_smpl(info, true);
475
476	device_init_wakeup(&pdev->dev, 1);
477
478	info->rtc_dev = devm_rtc_device_register(&pdev->dev, "max8997-rtc",
479					&max8997_rtc_ops, THIS_MODULE);
480
481	if (IS_ERR(info->rtc_dev)) {
482		ret = PTR_ERR(info->rtc_dev);
483		dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
484		return ret;
485	}
486
487	virq = irq_create_mapping(max8997->irq_domain, MAX8997_PMICIRQ_RTCA1);
488	if (!virq) {
489		dev_err(&pdev->dev, "Failed to create mapping alarm IRQ\n");
490		ret = -ENXIO;
491		goto err_out;
492	}
493	info->virq = virq;
494
495	ret = devm_request_threaded_irq(&pdev->dev, virq, NULL,
496				max8997_rtc_alarm_irq, 0,
497				"rtc-alarm0", info);
498	if (ret < 0)
499		dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
500			info->virq, ret);
501
502err_out:
503	return ret;
504}
505
506static void max8997_rtc_shutdown(struct platform_device *pdev)
507{
508	struct max8997_rtc_info *info = platform_get_drvdata(pdev);
509
510	max8997_rtc_enable_wtsr(info, false);
511	max8997_rtc_enable_smpl(info, false);
512}
513
514static const struct platform_device_id rtc_id[] = {
515	{ "max8997-rtc", 0 },
516	{},
517};
518MODULE_DEVICE_TABLE(platform, rtc_id);
519
520static struct platform_driver max8997_rtc_driver = {
521	.driver		= {
522		.name	= "max8997-rtc",
523	},
524	.probe		= max8997_rtc_probe,
525	.shutdown	= max8997_rtc_shutdown,
526	.id_table	= rtc_id,
527};
528
529module_platform_driver(max8997_rtc_driver);
530
531MODULE_DESCRIPTION("Maxim MAX8997 RTC driver");
532MODULE_AUTHOR("<ms925.kim@samsung.com>");
533MODULE_LICENSE("GPL");
v4.6
  1/*
  2 * RTC driver for Maxim MAX8997
  3 *
  4 * Copyright (C) 2013 Samsung Electronics Co.Ltd
  5 *
  6 *  based on rtc-max8998.c
  7 *
  8 *  This program is free software; you can redistribute  it and/or modify it
  9 *  under  the terms of  the GNU General  Public License as published by the
 10 *  Free Software Foundation;  either version 2 of the  License, or (at your
 11 *  option) any later version.
 12 *
 13 */
 14
 15#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 16
 17#include <linux/slab.h>
 18#include <linux/rtc.h>
 19#include <linux/delay.h>
 20#include <linux/mutex.h>
 21#include <linux/module.h>
 22#include <linux/platform_device.h>
 23#include <linux/mfd/max8997-private.h>
 24#include <linux/irqdomain.h>
 25
 26/* Module parameter for WTSR function control */
 27static int wtsr_en = 1;
 28module_param(wtsr_en, int, 0444);
 29MODULE_PARM_DESC(wtsr_en, "Watchdog Timeout & Software Reset (default=on)");
 30/* Module parameter for SMPL function control */
 31static int smpl_en = 1;
 32module_param(smpl_en, int, 0444);
 33MODULE_PARM_DESC(smpl_en, "Sudden Momentary Power Loss (default=on)");
 34
 35/* RTC Control Register */
 36#define BCD_EN_SHIFT			0
 37#define BCD_EN_MASK			(1 << BCD_EN_SHIFT)
 38#define MODEL24_SHIFT			1
 39#define MODEL24_MASK			(1 << MODEL24_SHIFT)
 40/* RTC Update Register1 */
 41#define RTC_UDR_SHIFT			0
 42#define RTC_UDR_MASK			(1 << RTC_UDR_SHIFT)
 43/* WTSR and SMPL Register */
 44#define WTSRT_SHIFT			0
 45#define SMPLT_SHIFT			2
 46#define WTSR_EN_SHIFT			6
 47#define SMPL_EN_SHIFT			7
 48#define WTSRT_MASK			(3 << WTSRT_SHIFT)
 49#define SMPLT_MASK			(3 << SMPLT_SHIFT)
 50#define WTSR_EN_MASK			(1 << WTSR_EN_SHIFT)
 51#define SMPL_EN_MASK			(1 << SMPL_EN_SHIFT)
 52/* RTC Hour register */
 53#define HOUR_PM_SHIFT			6
 54#define HOUR_PM_MASK			(1 << HOUR_PM_SHIFT)
 55/* RTC Alarm Enable */
 56#define ALARM_ENABLE_SHIFT		7
 57#define ALARM_ENABLE_MASK		(1 << ALARM_ENABLE_SHIFT)
 58
 59enum {
 60	RTC_SEC = 0,
 61	RTC_MIN,
 62	RTC_HOUR,
 63	RTC_WEEKDAY,
 64	RTC_MONTH,
 65	RTC_YEAR,
 66	RTC_DATE,
 67	RTC_NR_TIME
 68};
 69
 70struct max8997_rtc_info {
 71	struct device		*dev;
 72	struct max8997_dev	*max8997;
 73	struct i2c_client	*rtc;
 74	struct rtc_device	*rtc_dev;
 75	struct mutex		lock;
 76	int virq;
 77	int rtc_24hr_mode;
 78};
 79
 80static void max8997_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
 81				   int rtc_24hr_mode)
 82{
 83	tm->tm_sec = data[RTC_SEC] & 0x7f;
 84	tm->tm_min = data[RTC_MIN] & 0x7f;
 85	if (rtc_24hr_mode)
 86		tm->tm_hour = data[RTC_HOUR] & 0x1f;
 87	else {
 88		tm->tm_hour = data[RTC_HOUR] & 0x0f;
 89		if (data[RTC_HOUR] & HOUR_PM_MASK)
 90			tm->tm_hour += 12;
 91	}
 92
 93	tm->tm_wday = fls(data[RTC_WEEKDAY] & 0x7f) - 1;
 94	tm->tm_mday = data[RTC_DATE] & 0x1f;
 95	tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1;
 96	tm->tm_year = (data[RTC_YEAR] & 0x7f) + 100;
 97	tm->tm_yday = 0;
 98	tm->tm_isdst = 0;
 99}
100
101static int max8997_rtc_tm_to_data(struct rtc_time *tm, u8 *data)
102{
103	data[RTC_SEC] = tm->tm_sec;
104	data[RTC_MIN] = tm->tm_min;
105	data[RTC_HOUR] = tm->tm_hour;
106	data[RTC_WEEKDAY] = 1 << tm->tm_wday;
107	data[RTC_DATE] = tm->tm_mday;
108	data[RTC_MONTH] = tm->tm_mon + 1;
109	data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
110
111	if (tm->tm_year < 100) {
112		pr_warn("RTC cannot handle the year %d.  Assume it's 2000.\n",
113			1900 + tm->tm_year);
114		return -EINVAL;
115	}
116	return 0;
117}
118
119static inline int max8997_rtc_set_update_reg(struct max8997_rtc_info *info)
120{
121	int ret;
122
123	ret = max8997_write_reg(info->rtc, MAX8997_RTC_UPDATE1,
124						RTC_UDR_MASK);
125	if (ret < 0)
126		dev_err(info->dev, "%s: fail to write update reg(%d)\n",
127				__func__, ret);
128	else {
129		/* Minimum 16ms delay required before RTC update.
130		 * Otherwise, we may read and update based on out-of-date
131		 * value */
132		msleep(20);
133	}
134
135	return ret;
136}
137
138static int max8997_rtc_read_time(struct device *dev, struct rtc_time *tm)
139{
140	struct max8997_rtc_info *info = dev_get_drvdata(dev);
141	u8 data[RTC_NR_TIME];
142	int ret;
143
144	mutex_lock(&info->lock);
145	ret = max8997_bulk_read(info->rtc, MAX8997_RTC_SEC, RTC_NR_TIME, data);
146	mutex_unlock(&info->lock);
147
148	if (ret < 0) {
149		dev_err(info->dev, "%s: fail to read time reg(%d)\n", __func__,
150				ret);
151		return ret;
152	}
153
154	max8997_rtc_data_to_tm(data, tm, info->rtc_24hr_mode);
155
156	return rtc_valid_tm(tm);
157}
158
159static int max8997_rtc_set_time(struct device *dev, struct rtc_time *tm)
160{
161	struct max8997_rtc_info *info = dev_get_drvdata(dev);
162	u8 data[RTC_NR_TIME];
163	int ret;
164
165	ret = max8997_rtc_tm_to_data(tm, data);
166	if (ret < 0)
167		return ret;
168
169	mutex_lock(&info->lock);
170
171	ret = max8997_bulk_write(info->rtc, MAX8997_RTC_SEC, RTC_NR_TIME, data);
172	if (ret < 0) {
173		dev_err(info->dev, "%s: fail to write time reg(%d)\n", __func__,
174				ret);
175		goto out;
176	}
177
178	ret = max8997_rtc_set_update_reg(info);
179out:
180	mutex_unlock(&info->lock);
181	return ret;
182}
183
184static int max8997_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
185{
186	struct max8997_rtc_info *info = dev_get_drvdata(dev);
187	u8 data[RTC_NR_TIME];
188	u8 val;
189	int i, ret;
190
191	mutex_lock(&info->lock);
192
193	ret = max8997_bulk_read(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
194			data);
195	if (ret < 0) {
196		dev_err(info->dev, "%s:%d fail to read alarm reg(%d)\n",
197				__func__, __LINE__, ret);
198		goto out;
199	}
200
201	max8997_rtc_data_to_tm(data, &alrm->time, info->rtc_24hr_mode);
202
203	alrm->enabled = 0;
204	for (i = 0; i < RTC_NR_TIME; i++) {
205		if (data[i] & ALARM_ENABLE_MASK) {
206			alrm->enabled = 1;
207			break;
208		}
209	}
210
211	alrm->pending = 0;
212	ret = max8997_read_reg(info->max8997->i2c, MAX8997_REG_STATUS1, &val);
213	if (ret < 0) {
214		dev_err(info->dev, "%s:%d fail to read status1 reg(%d)\n",
215				__func__, __LINE__, ret);
216		goto out;
217	}
218
219	if (val & (1 << 4)) /* RTCA1 */
220		alrm->pending = 1;
221
222out:
223	mutex_unlock(&info->lock);
224	return 0;
225}
226
227static int max8997_rtc_stop_alarm(struct max8997_rtc_info *info)
228{
229	u8 data[RTC_NR_TIME];
230	int ret, i;
231
232	if (!mutex_is_locked(&info->lock))
233		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
234
235	ret = max8997_bulk_read(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
236				data);
237	if (ret < 0) {
238		dev_err(info->dev, "%s: fail to read alarm reg(%d)\n",
239				__func__, ret);
240		goto out;
241	}
242
243	for (i = 0; i < RTC_NR_TIME; i++)
244		data[i] &= ~ALARM_ENABLE_MASK;
245
246	ret = max8997_bulk_write(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
247				 data);
248	if (ret < 0) {
249		dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
250				__func__, ret);
251		goto out;
252	}
253
254	ret = max8997_rtc_set_update_reg(info);
255out:
256	return ret;
257}
258
259static int max8997_rtc_start_alarm(struct max8997_rtc_info *info)
260{
261	u8 data[RTC_NR_TIME];
262	int ret;
263
264	if (!mutex_is_locked(&info->lock))
265		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
266
267	ret = max8997_bulk_read(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
268				data);
269	if (ret < 0) {
270		dev_err(info->dev, "%s: fail to read alarm reg(%d)\n",
271				__func__, ret);
272		goto out;
273	}
274
275	data[RTC_SEC] |= (1 << ALARM_ENABLE_SHIFT);
276	data[RTC_MIN] |= (1 << ALARM_ENABLE_SHIFT);
277	data[RTC_HOUR] |= (1 << ALARM_ENABLE_SHIFT);
278	data[RTC_WEEKDAY] &= ~ALARM_ENABLE_MASK;
279	if (data[RTC_MONTH] & 0xf)
280		data[RTC_MONTH] |= (1 << ALARM_ENABLE_SHIFT);
281	if (data[RTC_YEAR] & 0x7f)
282		data[RTC_YEAR] |= (1 << ALARM_ENABLE_SHIFT);
283	if (data[RTC_DATE] & 0x1f)
284		data[RTC_DATE] |= (1 << ALARM_ENABLE_SHIFT);
285
286	ret = max8997_bulk_write(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
287				 data);
288	if (ret < 0) {
289		dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
290				__func__, ret);
291		goto out;
292	}
293
294	ret = max8997_rtc_set_update_reg(info);
295out:
296	return ret;
297}
298static int max8997_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
299{
300	struct max8997_rtc_info *info = dev_get_drvdata(dev);
301	u8 data[RTC_NR_TIME];
302	int ret;
303
304	ret = max8997_rtc_tm_to_data(&alrm->time, data);
305	if (ret < 0)
306		return ret;
307
308	dev_info(info->dev, "%s: %d-%02d-%02d %02d:%02d:%02d\n", __func__,
309			data[RTC_YEAR] + 2000, data[RTC_MONTH], data[RTC_DATE],
310			data[RTC_HOUR], data[RTC_MIN], data[RTC_SEC]);
311
312	mutex_lock(&info->lock);
313
314	ret = max8997_rtc_stop_alarm(info);
315	if (ret < 0)
316		goto out;
317
318	ret = max8997_bulk_write(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
319				data);
320	if (ret < 0) {
321		dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
322				__func__, ret);
323		goto out;
324	}
325
326	ret = max8997_rtc_set_update_reg(info);
327	if (ret < 0)
328		goto out;
329
330	if (alrm->enabled)
331		ret = max8997_rtc_start_alarm(info);
332out:
333	mutex_unlock(&info->lock);
334	return ret;
335}
336
337static int max8997_rtc_alarm_irq_enable(struct device *dev,
338					unsigned int enabled)
339{
340	struct max8997_rtc_info *info = dev_get_drvdata(dev);
341	int ret;
342
343	mutex_lock(&info->lock);
344	if (enabled)
345		ret = max8997_rtc_start_alarm(info);
346	else
347		ret = max8997_rtc_stop_alarm(info);
348	mutex_unlock(&info->lock);
349
350	return ret;
351}
352
353static irqreturn_t max8997_rtc_alarm_irq(int irq, void *data)
354{
355	struct max8997_rtc_info *info = data;
356
357	dev_info(info->dev, "%s:irq(%d)\n", __func__, irq);
358
359	rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
360
361	return IRQ_HANDLED;
362}
363
364static const struct rtc_class_ops max8997_rtc_ops = {
365	.read_time = max8997_rtc_read_time,
366	.set_time = max8997_rtc_set_time,
367	.read_alarm = max8997_rtc_read_alarm,
368	.set_alarm = max8997_rtc_set_alarm,
369	.alarm_irq_enable = max8997_rtc_alarm_irq_enable,
370};
371
372static void max8997_rtc_enable_wtsr(struct max8997_rtc_info *info, bool enable)
373{
374	int ret;
375	u8 val, mask;
376
377	if (!wtsr_en)
378		return;
379
380	if (enable)
381		val = (1 << WTSR_EN_SHIFT) | (3 << WTSRT_SHIFT);
382	else
383		val = 0;
384
385	mask = WTSR_EN_MASK | WTSRT_MASK;
386
387	dev_info(info->dev, "%s: %s WTSR\n", __func__,
388			enable ? "enable" : "disable");
389
390	ret = max8997_update_reg(info->rtc, MAX8997_RTC_WTSR_SMPL, val, mask);
391	if (ret < 0) {
392		dev_err(info->dev, "%s: fail to update WTSR reg(%d)\n",
393				__func__, ret);
394		return;
395	}
396
397	max8997_rtc_set_update_reg(info);
398}
399
400static void max8997_rtc_enable_smpl(struct max8997_rtc_info *info, bool enable)
401{
402	int ret;
403	u8 val, mask;
404
405	if (!smpl_en)
406		return;
407
408	if (enable)
409		val = (1 << SMPL_EN_SHIFT) | (0 << SMPLT_SHIFT);
410	else
411		val = 0;
412
413	mask = SMPL_EN_MASK | SMPLT_MASK;
414
415	dev_info(info->dev, "%s: %s SMPL\n", __func__,
416			enable ? "enable" : "disable");
417
418	ret = max8997_update_reg(info->rtc, MAX8997_RTC_WTSR_SMPL, val, mask);
419	if (ret < 0) {
420		dev_err(info->dev, "%s: fail to update SMPL reg(%d)\n",
421				__func__, ret);
422		return;
423	}
424
425	max8997_rtc_set_update_reg(info);
426
427	val = 0;
428	max8997_read_reg(info->rtc, MAX8997_RTC_WTSR_SMPL, &val);
429	pr_info("WTSR_SMPL(0x%02x)\n", val);
430}
431
432static int max8997_rtc_init_reg(struct max8997_rtc_info *info)
433{
434	u8 data[2];
435	int ret;
436
437	/* Set RTC control register : Binary mode, 24hour mdoe */
438	data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
439	data[1] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
440
441	info->rtc_24hr_mode = 1;
442
443	ret = max8997_bulk_write(info->rtc, MAX8997_RTC_CTRLMASK, 2, data);
444	if (ret < 0) {
445		dev_err(info->dev, "%s: fail to write controlm reg(%d)\n",
446				__func__, ret);
447		return ret;
448	}
449
450	ret = max8997_rtc_set_update_reg(info);
451	return ret;
452}
453
454static int max8997_rtc_probe(struct platform_device *pdev)
455{
456	struct max8997_dev *max8997 = dev_get_drvdata(pdev->dev.parent);
457	struct max8997_rtc_info *info;
458	int ret, virq;
459
460	info = devm_kzalloc(&pdev->dev, sizeof(struct max8997_rtc_info),
461			GFP_KERNEL);
462	if (!info)
463		return -ENOMEM;
464
465	mutex_init(&info->lock);
466	info->dev = &pdev->dev;
467	info->max8997 = max8997;
468	info->rtc = max8997->rtc;
469
470	platform_set_drvdata(pdev, info);
471
472	ret = max8997_rtc_init_reg(info);
473
474	if (ret < 0) {
475		dev_err(&pdev->dev, "Failed to initialize RTC reg:%d\n", ret);
476		return ret;
477	}
478
479	max8997_rtc_enable_wtsr(info, true);
480	max8997_rtc_enable_smpl(info, true);
481
482	device_init_wakeup(&pdev->dev, 1);
483
484	info->rtc_dev = devm_rtc_device_register(&pdev->dev, "max8997-rtc",
485					&max8997_rtc_ops, THIS_MODULE);
486
487	if (IS_ERR(info->rtc_dev)) {
488		ret = PTR_ERR(info->rtc_dev);
489		dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
490		return ret;
491	}
492
493	virq = irq_create_mapping(max8997->irq_domain, MAX8997_PMICIRQ_RTCA1);
494	if (!virq) {
495		dev_err(&pdev->dev, "Failed to create mapping alarm IRQ\n");
496		ret = -ENXIO;
497		goto err_out;
498	}
499	info->virq = virq;
500
501	ret = devm_request_threaded_irq(&pdev->dev, virq, NULL,
502				max8997_rtc_alarm_irq, 0,
503				"rtc-alarm0", info);
504	if (ret < 0)
505		dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
506			info->virq, ret);
507
508err_out:
509	return ret;
510}
511
512static void max8997_rtc_shutdown(struct platform_device *pdev)
513{
514	struct max8997_rtc_info *info = platform_get_drvdata(pdev);
515
516	max8997_rtc_enable_wtsr(info, false);
517	max8997_rtc_enable_smpl(info, false);
518}
519
520static const struct platform_device_id rtc_id[] = {
521	{ "max8997-rtc", 0 },
522	{},
523};
524MODULE_DEVICE_TABLE(platform, rtc_id);
525
526static struct platform_driver max8997_rtc_driver = {
527	.driver		= {
528		.name	= "max8997-rtc",
529	},
530	.probe		= max8997_rtc_probe,
531	.shutdown	= max8997_rtc_shutdown,
532	.id_table	= rtc_id,
533};
534
535module_platform_driver(max8997_rtc_driver);
536
537MODULE_DESCRIPTION("Maxim MAX8997 RTC driver");
538MODULE_AUTHOR("<ms925.kim@samsung.com>");
539MODULE_LICENSE("GPL");