2 * RTC driver for Maxim MAX77686
4 * Copyright (C) 2012 Samsung Electronics Co.Ltd
6 * based on rtc-max8997.c
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.
15 #include <linux/slab.h>
16 #include <linux/rtc.h>
17 #include <linux/delay.h>
18 #include <linux/mutex.h>
19 #include <linux/module.h>
20 #include <linux/platform_device.h>
21 #include <linux/mfd/max77686-private.h>
22 #include <linux/irqdomain.h>
23 #include <linux/regmap.h>
25 /* RTC Control Register */
26 #define BCD_EN_SHIFT 0
27 #define BCD_EN_MASK (1 << BCD_EN_SHIFT)
28 #define MODEL24_SHIFT 1
29 #define MODEL24_MASK (1 << MODEL24_SHIFT)
30 /* RTC Update Register1 */
31 #define RTC_UDR_SHIFT 0
32 #define RTC_UDR_MASK (1 << RTC_UDR_SHIFT)
33 #define RTC_RBUDR_SHIFT 4
34 #define RTC_RBUDR_MASK (1 << RTC_RBUDR_SHIFT)
35 /* RTC Hour register */
36 #define HOUR_PM_SHIFT 6
37 #define HOUR_PM_MASK (1 << HOUR_PM_SHIFT)
38 /* RTC Alarm Enable */
39 #define ALARM_ENABLE_SHIFT 7
40 #define ALARM_ENABLE_MASK (1 << ALARM_ENABLE_SHIFT)
42 #define MAX77686_RTC_UPDATE_DELAY 16
55 struct max77686_rtc_info {
57 struct max77686_dev *max77686;
58 struct i2c_client *rtc;
59 struct rtc_device *rtc_dev;
62 struct regmap *regmap;
68 enum MAX77686_RTC_OP {
73 static inline int max77686_rtc_calculate_wday(u8 shifted)
83 static void max77686_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
86 tm->tm_sec = data[RTC_SEC] & 0x7f;
87 tm->tm_min = data[RTC_MIN] & 0x7f;
89 tm->tm_hour = data[RTC_HOUR] & 0x1f;
91 tm->tm_hour = data[RTC_HOUR] & 0x0f;
92 if (data[RTC_HOUR] & HOUR_PM_MASK)
96 tm->tm_wday = max77686_rtc_calculate_wday(data[RTC_WEEKDAY] & 0x7f);
97 tm->tm_mday = data[RTC_DATE] & 0x1f;
98 tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1;
99 tm->tm_year = (data[RTC_YEAR] & 0x7f) + 100;
104 static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data)
106 data[RTC_SEC] = tm->tm_sec;
107 data[RTC_MIN] = tm->tm_min;
108 data[RTC_HOUR] = tm->tm_hour;
109 data[RTC_WEEKDAY] = 1 << tm->tm_wday;
110 data[RTC_DATE] = tm->tm_mday;
111 data[RTC_MONTH] = tm->tm_mon + 1;
112 data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
114 if (tm->tm_year < 100) {
115 pr_warn("%s: MAX77686 RTC cannot handle the year %d."
116 "Assume it's 2000.\n", __func__, 1900 + tm->tm_year);
122 static int max77686_rtc_update(struct max77686_rtc_info *info,
123 enum MAX77686_RTC_OP op)
128 if (op == MAX77686_RTC_WRITE)
129 data = 1 << RTC_UDR_SHIFT;
131 data = 1 << RTC_RBUDR_SHIFT;
133 ret = regmap_update_bits(info->max77686->rtc_regmap,
134 MAX77686_RTC_UPDATE0, data, data);
136 dev_err(info->dev, "%s: fail to write update reg(ret=%d, data=0x%x)\n",
137 __func__, ret, data);
139 /* Minimum 16ms delay required before RTC update. */
140 msleep(MAX77686_RTC_UPDATE_DELAY);
146 static int max77686_rtc_read_time(struct device *dev, struct rtc_time *tm)
148 struct max77686_rtc_info *info = dev_get_drvdata(dev);
149 u8 data[RTC_NR_TIME];
152 mutex_lock(&info->lock);
154 ret = max77686_rtc_update(info, MAX77686_RTC_READ);
158 ret = regmap_bulk_read(info->max77686->rtc_regmap,
159 MAX77686_RTC_SEC, data, RTC_NR_TIME);
161 dev_err(info->dev, "%s: fail to read time reg(%d)\n", __func__, ret);
165 max77686_rtc_data_to_tm(data, tm, info->rtc_24hr_mode);
167 ret = rtc_valid_tm(tm);
170 mutex_unlock(&info->lock);
174 static int max77686_rtc_set_time(struct device *dev, struct rtc_time *tm)
176 struct max77686_rtc_info *info = dev_get_drvdata(dev);
177 u8 data[RTC_NR_TIME];
180 ret = max77686_rtc_tm_to_data(tm, data);
184 mutex_lock(&info->lock);
186 ret = regmap_bulk_write(info->max77686->rtc_regmap,
187 MAX77686_RTC_SEC, data, RTC_NR_TIME);
189 dev_err(info->dev, "%s: fail to write time reg(%d)\n", __func__,
194 ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
197 mutex_unlock(&info->lock);
201 static int max77686_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
203 struct max77686_rtc_info *info = dev_get_drvdata(dev);
204 u8 data[RTC_NR_TIME];
208 mutex_lock(&info->lock);
210 ret = max77686_rtc_update(info, MAX77686_RTC_READ);
214 ret = regmap_bulk_read(info->max77686->rtc_regmap,
215 MAX77686_ALARM1_SEC, data, RTC_NR_TIME);
217 dev_err(info->dev, "%s:%d fail to read alarm reg(%d)\n",
218 __func__, __LINE__, ret);
222 max77686_rtc_data_to_tm(data, &alrm->time, info->rtc_24hr_mode);
225 for (i = 0; i < RTC_NR_TIME; i++) {
226 if (data[i] & ALARM_ENABLE_MASK) {
233 ret = regmap_read(info->max77686->regmap, MAX77686_REG_STATUS2, &val);
235 dev_err(info->dev, "%s:%d fail to read status2 reg(%d)\n",
236 __func__, __LINE__, ret);
240 if (val & (1 << 4)) /* RTCA1 */
244 mutex_unlock(&info->lock);
248 static int max77686_rtc_stop_alarm(struct max77686_rtc_info *info)
250 u8 data[RTC_NR_TIME];
254 if (!mutex_is_locked(&info->lock))
255 dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
257 ret = max77686_rtc_update(info, MAX77686_RTC_READ);
261 ret = regmap_bulk_read(info->max77686->rtc_regmap,
262 MAX77686_ALARM1_SEC, data, RTC_NR_TIME);
264 dev_err(info->dev, "%s: fail to read alarm reg(%d)\n",
269 max77686_rtc_data_to_tm(data, &tm, info->rtc_24hr_mode);
271 for (i = 0; i < RTC_NR_TIME; i++)
272 data[i] &= ~ALARM_ENABLE_MASK;
274 ret = regmap_bulk_write(info->max77686->rtc_regmap,
275 MAX77686_ALARM1_SEC, data, RTC_NR_TIME);
277 dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
282 ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
287 static int max77686_rtc_start_alarm(struct max77686_rtc_info *info)
289 u8 data[RTC_NR_TIME];
293 if (!mutex_is_locked(&info->lock))
294 dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
296 ret = max77686_rtc_update(info, MAX77686_RTC_READ);
300 ret = regmap_bulk_read(info->max77686->rtc_regmap,
301 MAX77686_ALARM1_SEC, data, RTC_NR_TIME);
303 dev_err(info->dev, "%s: fail to read alarm reg(%d)\n",
308 max77686_rtc_data_to_tm(data, &tm, info->rtc_24hr_mode);
310 data[RTC_SEC] |= (1 << ALARM_ENABLE_SHIFT);
311 data[RTC_MIN] |= (1 << ALARM_ENABLE_SHIFT);
312 data[RTC_HOUR] |= (1 << ALARM_ENABLE_SHIFT);
313 data[RTC_WEEKDAY] &= ~ALARM_ENABLE_MASK;
314 if (data[RTC_MONTH] & 0xf)
315 data[RTC_MONTH] |= (1 << ALARM_ENABLE_SHIFT);
316 if (data[RTC_YEAR] & 0x7f)
317 data[RTC_YEAR] |= (1 << ALARM_ENABLE_SHIFT);
318 if (data[RTC_DATE] & 0x1f)
319 data[RTC_DATE] |= (1 << ALARM_ENABLE_SHIFT);
321 ret = regmap_bulk_write(info->max77686->rtc_regmap,
322 MAX77686_ALARM1_SEC, data, RTC_NR_TIME);
324 dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
329 ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
334 static int max77686_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
336 struct max77686_rtc_info *info = dev_get_drvdata(dev);
337 u8 data[RTC_NR_TIME];
340 ret = max77686_rtc_tm_to_data(&alrm->time, data);
344 mutex_lock(&info->lock);
346 ret = max77686_rtc_stop_alarm(info);
350 ret = regmap_bulk_write(info->max77686->rtc_regmap,
351 MAX77686_ALARM1_SEC, data, RTC_NR_TIME);
354 dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
359 ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
364 ret = max77686_rtc_start_alarm(info);
366 mutex_unlock(&info->lock);
370 static int max77686_rtc_alarm_irq_enable(struct device *dev,
371 unsigned int enabled)
373 struct max77686_rtc_info *info = dev_get_drvdata(dev);
376 mutex_lock(&info->lock);
378 ret = max77686_rtc_start_alarm(info);
380 ret = max77686_rtc_stop_alarm(info);
381 mutex_unlock(&info->lock);
386 static irqreturn_t max77686_rtc_alarm_irq(int irq, void *data)
388 struct max77686_rtc_info *info = data;
390 dev_info(info->dev, "%s:irq(%d)\n", __func__, irq);
392 rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
397 static const struct rtc_class_ops max77686_rtc_ops = {
398 .read_time = max77686_rtc_read_time,
399 .set_time = max77686_rtc_set_time,
400 .read_alarm = max77686_rtc_read_alarm,
401 .set_alarm = max77686_rtc_set_alarm,
402 .alarm_irq_enable = max77686_rtc_alarm_irq_enable,
405 static int max77686_rtc_init_reg(struct max77686_rtc_info *info)
410 /* Set RTC control register : Binary mode, 24hour mdoe */
411 data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
412 data[1] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
414 info->rtc_24hr_mode = 1;
416 ret = regmap_bulk_write(info->max77686->rtc_regmap, MAX77686_RTC_CONTROLM, data, 2);
418 dev_err(info->dev, "%s: fail to write controlm reg(%d)\n",
423 ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
427 static int max77686_rtc_probe(struct platform_device *pdev)
429 struct max77686_dev *max77686 = dev_get_drvdata(pdev->dev.parent);
430 struct max77686_rtc_info *info;
433 dev_info(&pdev->dev, "%s\n", __func__);
435 info = devm_kzalloc(&pdev->dev, sizeof(struct max77686_rtc_info),
440 mutex_init(&info->lock);
441 info->dev = &pdev->dev;
442 info->max77686 = max77686;
443 info->rtc = max77686->rtc;
445 platform_set_drvdata(pdev, info);
447 ret = max77686_rtc_init_reg(info);
450 dev_err(&pdev->dev, "Failed to initialize RTC reg:%d\n", ret);
454 device_init_wakeup(&pdev->dev, 1);
456 info->rtc_dev = devm_rtc_device_register(&pdev->dev, "max77686-rtc",
457 &max77686_rtc_ops, THIS_MODULE);
459 if (IS_ERR(info->rtc_dev)) {
460 dev_info(&pdev->dev, "%s: fail\n", __func__);
462 ret = PTR_ERR(info->rtc_dev);
463 dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
469 info->virq = regmap_irq_get_virq(max77686->rtc_irq_data,
470 MAX77686_RTCIRQ_RTCA1);
476 ret = devm_request_threaded_irq(&pdev->dev, info->virq, NULL,
477 max77686_rtc_alarm_irq, 0, "rtc-alarm1", info);
479 dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
486 #ifdef CONFIG_PM_SLEEP
487 static int max77686_rtc_suspend(struct device *dev)
489 if (device_may_wakeup(dev)) {
490 struct max77686_rtc_info *info = dev_get_drvdata(dev);
492 return enable_irq_wake(info->virq);
498 static int max77686_rtc_resume(struct device *dev)
500 if (device_may_wakeup(dev)) {
501 struct max77686_rtc_info *info = dev_get_drvdata(dev);
503 return disable_irq_wake(info->virq);
510 static SIMPLE_DEV_PM_OPS(max77686_rtc_pm_ops,
511 max77686_rtc_suspend, max77686_rtc_resume);
513 static const struct platform_device_id rtc_id[] = {
514 { "max77686-rtc", 0 },
518 static struct platform_driver max77686_rtc_driver = {
520 .name = "max77686-rtc",
521 .owner = THIS_MODULE,
522 .pm = &max77686_rtc_pm_ops,
524 .probe = max77686_rtc_probe,
528 module_platform_driver(max77686_rtc_driver);
530 MODULE_DESCRIPTION("Maxim MAX77686 RTC driver");
531 MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
532 MODULE_LICENSE("GPL");