Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 856 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-max77686.c b/drivers/rtc/rtc-max77686.c
new file mode 100644
index 000000000..8e09450d1
--- /dev/null
+++ b/drivers/rtc/rtc-max77686.c
@@ -0,0 +1,856 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// RTC driver for Maxim MAX77686 and MAX77802
+//
+// Copyright (C) 2012 Samsung Electronics Co.Ltd
+//
+//  based on rtc-max8997.c
+
+#include <linux/i2c.h>
+#include <linux/slab.h>
+#include <linux/rtc.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/max77686-private.h>
+#include <linux/irqdomain.h>
+#include <linux/regmap.h>
+
+#define MAX77686_I2C_ADDR_RTC		(0x0C >> 1)
+#define MAX77620_I2C_ADDR_RTC		0x68
+#define MAX77686_INVALID_I2C_ADDR	(-1)
+
+/* Define non existing register */
+#define MAX77686_INVALID_REG		(-1)
+
+/* RTC Control Register */
+#define BCD_EN_SHIFT			0
+#define BCD_EN_MASK			BIT(BCD_EN_SHIFT)
+#define MODEL24_SHIFT			1
+#define MODEL24_MASK			BIT(MODEL24_SHIFT)
+/* RTC Update Register1 */
+#define RTC_UDR_SHIFT			0
+#define RTC_UDR_MASK			BIT(RTC_UDR_SHIFT)
+#define RTC_RBUDR_SHIFT			4
+#define RTC_RBUDR_MASK			BIT(RTC_RBUDR_SHIFT)
+/* RTC Hour register */
+#define HOUR_PM_SHIFT			6
+#define HOUR_PM_MASK			BIT(HOUR_PM_SHIFT)
+/* RTC Alarm Enable */
+#define ALARM_ENABLE_SHIFT		7
+#define ALARM_ENABLE_MASK		BIT(ALARM_ENABLE_SHIFT)
+
+#define REG_RTC_NONE			0xdeadbeef
+
+/*
+ * MAX77802 has separate register (RTCAE1) for alarm enable instead
+ * using 1 bit from registers RTC{SEC,MIN,HOUR,DAY,MONTH,YEAR,DATE}
+ * as in done in MAX77686.
+ */
+#define MAX77802_ALARM_ENABLE_VALUE	0x77
+
+enum {
+	RTC_SEC = 0,
+	RTC_MIN,
+	RTC_HOUR,
+	RTC_WEEKDAY,
+	RTC_MONTH,
+	RTC_YEAR,
+	RTC_DATE,
+	RTC_NR_TIME
+};
+
+struct max77686_rtc_driver_data {
+	/* Minimum usecs needed for a RTC update */
+	unsigned long		delay;
+	/* Mask used to read RTC registers value */
+	u8			mask;
+	/* Registers offset to I2C addresses map */
+	const unsigned int	*map;
+	/* Has a separate alarm enable register? */
+	bool			alarm_enable_reg;
+	/* I2C address for RTC block */
+	int			rtc_i2c_addr;
+	/* RTC interrupt via platform resource */
+	bool			rtc_irq_from_platform;
+	/* Pending alarm status register */
+	int			alarm_pending_status_reg;
+	/* RTC IRQ CHIP for regmap */
+	const struct regmap_irq_chip *rtc_irq_chip;
+};
+
+struct max77686_rtc_info {
+	struct device		*dev;
+	struct i2c_client	*rtc;
+	struct rtc_device	*rtc_dev;
+	struct mutex		lock;
+
+	struct regmap		*regmap;
+	struct regmap		*rtc_regmap;
+
+	const struct max77686_rtc_driver_data *drv_data;
+	struct regmap_irq_chip_data *rtc_irq_data;
+
+	int rtc_irq;
+	int virq;
+	int rtc_24hr_mode;
+};
+
+enum MAX77686_RTC_OP {
+	MAX77686_RTC_WRITE,
+	MAX77686_RTC_READ,
+};
+
+/* These are not registers but just offsets that are mapped to addresses */
+enum max77686_rtc_reg_offset {
+	REG_RTC_CONTROLM = 0,
+	REG_RTC_CONTROL,
+	REG_RTC_UPDATE0,
+	REG_WTSR_SMPL_CNTL,
+	REG_RTC_SEC,
+	REG_RTC_MIN,
+	REG_RTC_HOUR,
+	REG_RTC_WEEKDAY,
+	REG_RTC_MONTH,
+	REG_RTC_YEAR,
+	REG_RTC_DATE,
+	REG_ALARM1_SEC,
+	REG_ALARM1_MIN,
+	REG_ALARM1_HOUR,
+	REG_ALARM1_WEEKDAY,
+	REG_ALARM1_MONTH,
+	REG_ALARM1_YEAR,
+	REG_ALARM1_DATE,
+	REG_ALARM2_SEC,
+	REG_ALARM2_MIN,
+	REG_ALARM2_HOUR,
+	REG_ALARM2_WEEKDAY,
+	REG_ALARM2_MONTH,
+	REG_ALARM2_YEAR,
+	REG_ALARM2_DATE,
+	REG_RTC_AE1,
+	REG_RTC_END,
+};
+
+/* Maps RTC registers offset to the MAX77686 register addresses */
+static const unsigned int max77686_map[REG_RTC_END] = {
+	[REG_RTC_CONTROLM]   = MAX77686_RTC_CONTROLM,
+	[REG_RTC_CONTROL]    = MAX77686_RTC_CONTROL,
+	[REG_RTC_UPDATE0]    = MAX77686_RTC_UPDATE0,
+	[REG_WTSR_SMPL_CNTL] = MAX77686_WTSR_SMPL_CNTL,
+	[REG_RTC_SEC]        = MAX77686_RTC_SEC,
+	[REG_RTC_MIN]        = MAX77686_RTC_MIN,
+	[REG_RTC_HOUR]       = MAX77686_RTC_HOUR,
+	[REG_RTC_WEEKDAY]    = MAX77686_RTC_WEEKDAY,
+	[REG_RTC_MONTH]      = MAX77686_RTC_MONTH,
+	[REG_RTC_YEAR]       = MAX77686_RTC_YEAR,
+	[REG_RTC_DATE]       = MAX77686_RTC_DATE,
+	[REG_ALARM1_SEC]     = MAX77686_ALARM1_SEC,
+	[REG_ALARM1_MIN]     = MAX77686_ALARM1_MIN,
+	[REG_ALARM1_HOUR]    = MAX77686_ALARM1_HOUR,
+	[REG_ALARM1_WEEKDAY] = MAX77686_ALARM1_WEEKDAY,
+	[REG_ALARM1_MONTH]   = MAX77686_ALARM1_MONTH,
+	[REG_ALARM1_YEAR]    = MAX77686_ALARM1_YEAR,
+	[REG_ALARM1_DATE]    = MAX77686_ALARM1_DATE,
+	[REG_ALARM2_SEC]     = MAX77686_ALARM2_SEC,
+	[REG_ALARM2_MIN]     = MAX77686_ALARM2_MIN,
+	[REG_ALARM2_HOUR]    = MAX77686_ALARM2_HOUR,
+	[REG_ALARM2_WEEKDAY] = MAX77686_ALARM2_WEEKDAY,
+	[REG_ALARM2_MONTH]   = MAX77686_ALARM2_MONTH,
+	[REG_ALARM2_YEAR]    = MAX77686_ALARM2_YEAR,
+	[REG_ALARM2_DATE]    = MAX77686_ALARM2_DATE,
+	[REG_RTC_AE1]	     = REG_RTC_NONE,
+};
+
+static const struct regmap_irq max77686_rtc_irqs[] = {
+	/* RTC interrupts */
+	REGMAP_IRQ_REG(0, 0, MAX77686_RTCINT_RTC60S_MSK),
+	REGMAP_IRQ_REG(1, 0, MAX77686_RTCINT_RTCA1_MSK),
+	REGMAP_IRQ_REG(2, 0, MAX77686_RTCINT_RTCA2_MSK),
+	REGMAP_IRQ_REG(3, 0, MAX77686_RTCINT_SMPL_MSK),
+	REGMAP_IRQ_REG(4, 0, MAX77686_RTCINT_RTC1S_MSK),
+	REGMAP_IRQ_REG(5, 0, MAX77686_RTCINT_WTSR_MSK),
+};
+
+static const struct regmap_irq_chip max77686_rtc_irq_chip = {
+	.name		= "max77686-rtc",
+	.status_base	= MAX77686_RTC_INT,
+	.mask_base	= MAX77686_RTC_INTM,
+	.num_regs	= 1,
+	.irqs		= max77686_rtc_irqs,
+	.num_irqs	= ARRAY_SIZE(max77686_rtc_irqs),
+};
+
+static const struct max77686_rtc_driver_data max77686_drv_data = {
+	.delay = 16000,
+	.mask  = 0x7f,
+	.map   = max77686_map,
+	.alarm_enable_reg  = false,
+	.rtc_irq_from_platform = false,
+	.alarm_pending_status_reg = MAX77686_REG_STATUS2,
+	.rtc_i2c_addr = MAX77686_I2C_ADDR_RTC,
+	.rtc_irq_chip = &max77686_rtc_irq_chip,
+};
+
+static const struct max77686_rtc_driver_data max77620_drv_data = {
+	.delay = 16000,
+	.mask  = 0x7f,
+	.map   = max77686_map,
+	.alarm_enable_reg  = false,
+	.rtc_irq_from_platform = true,
+	.alarm_pending_status_reg = MAX77686_INVALID_REG,
+	.rtc_i2c_addr = MAX77620_I2C_ADDR_RTC,
+	.rtc_irq_chip = &max77686_rtc_irq_chip,
+};
+
+static const unsigned int max77802_map[REG_RTC_END] = {
+	[REG_RTC_CONTROLM]   = MAX77802_RTC_CONTROLM,
+	[REG_RTC_CONTROL]    = MAX77802_RTC_CONTROL,
+	[REG_RTC_UPDATE0]    = MAX77802_RTC_UPDATE0,
+	[REG_WTSR_SMPL_CNTL] = MAX77802_WTSR_SMPL_CNTL,
+	[REG_RTC_SEC]        = MAX77802_RTC_SEC,
+	[REG_RTC_MIN]        = MAX77802_RTC_MIN,
+	[REG_RTC_HOUR]       = MAX77802_RTC_HOUR,
+	[REG_RTC_WEEKDAY]    = MAX77802_RTC_WEEKDAY,
+	[REG_RTC_MONTH]      = MAX77802_RTC_MONTH,
+	[REG_RTC_YEAR]       = MAX77802_RTC_YEAR,
+	[REG_RTC_DATE]       = MAX77802_RTC_DATE,
+	[REG_ALARM1_SEC]     = MAX77802_ALARM1_SEC,
+	[REG_ALARM1_MIN]     = MAX77802_ALARM1_MIN,
+	[REG_ALARM1_HOUR]    = MAX77802_ALARM1_HOUR,
+	[REG_ALARM1_WEEKDAY] = MAX77802_ALARM1_WEEKDAY,
+	[REG_ALARM1_MONTH]   = MAX77802_ALARM1_MONTH,
+	[REG_ALARM1_YEAR]    = MAX77802_ALARM1_YEAR,
+	[REG_ALARM1_DATE]    = MAX77802_ALARM1_DATE,
+	[REG_ALARM2_SEC]     = MAX77802_ALARM2_SEC,
+	[REG_ALARM2_MIN]     = MAX77802_ALARM2_MIN,
+	[REG_ALARM2_HOUR]    = MAX77802_ALARM2_HOUR,
+	[REG_ALARM2_WEEKDAY] = MAX77802_ALARM2_WEEKDAY,
+	[REG_ALARM2_MONTH]   = MAX77802_ALARM2_MONTH,
+	[REG_ALARM2_YEAR]    = MAX77802_ALARM2_YEAR,
+	[REG_ALARM2_DATE]    = MAX77802_ALARM2_DATE,
+	[REG_RTC_AE1]	     = MAX77802_RTC_AE1,
+};
+
+static const struct regmap_irq_chip max77802_rtc_irq_chip = {
+	.name		= "max77802-rtc",
+	.status_base	= MAX77802_RTC_INT,
+	.mask_base	= MAX77802_RTC_INTM,
+	.num_regs	= 1,
+	.irqs		= max77686_rtc_irqs, /* same masks as 77686 */
+	.num_irqs	= ARRAY_SIZE(max77686_rtc_irqs),
+};
+
+static const struct max77686_rtc_driver_data max77802_drv_data = {
+	.delay = 200,
+	.mask  = 0xff,
+	.map   = max77802_map,
+	.alarm_enable_reg  = true,
+	.rtc_irq_from_platform = false,
+	.alarm_pending_status_reg = MAX77686_REG_STATUS2,
+	.rtc_i2c_addr = MAX77686_INVALID_I2C_ADDR,
+	.rtc_irq_chip = &max77802_rtc_irq_chip,
+};
+
+static void max77686_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
+				    struct max77686_rtc_info *info)
+{
+	u8 mask = info->drv_data->mask;
+
+	tm->tm_sec = data[RTC_SEC] & mask;
+	tm->tm_min = data[RTC_MIN] & mask;
+	if (info->rtc_24hr_mode) {
+		tm->tm_hour = data[RTC_HOUR] & 0x1f;
+	} else {
+		tm->tm_hour = data[RTC_HOUR] & 0x0f;
+		if (data[RTC_HOUR] & HOUR_PM_MASK)
+			tm->tm_hour += 12;
+	}
+
+	/* Only a single bit is set in data[], so fls() would be equivalent */
+	tm->tm_wday = ffs(data[RTC_WEEKDAY] & mask) - 1;
+	tm->tm_mday = data[RTC_DATE] & 0x1f;
+	tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1;
+	tm->tm_year = data[RTC_YEAR] & mask;
+	tm->tm_yday = 0;
+	tm->tm_isdst = 0;
+
+	/*
+	 * MAX77686 uses 1 bit from sec/min/hour/etc RTC registers and the
+	 * year values are just 0..99 so add 100 to support up to 2099.
+	 */
+	if (!info->drv_data->alarm_enable_reg)
+		tm->tm_year += 100;
+}
+
+static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data,
+				   struct max77686_rtc_info *info)
+{
+	data[RTC_SEC] = tm->tm_sec;
+	data[RTC_MIN] = tm->tm_min;
+	data[RTC_HOUR] = tm->tm_hour;
+	data[RTC_WEEKDAY] = 1 << tm->tm_wday;
+	data[RTC_DATE] = tm->tm_mday;
+	data[RTC_MONTH] = tm->tm_mon + 1;
+
+	if (info->drv_data->alarm_enable_reg) {
+		data[RTC_YEAR] = tm->tm_year;
+		return 0;
+	}
+
+	data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
+
+	if (tm->tm_year < 100) {
+		dev_err(info->dev, "RTC cannot handle the year %d.\n",
+			1900 + tm->tm_year);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int max77686_rtc_update(struct max77686_rtc_info *info,
+			       enum MAX77686_RTC_OP op)
+{
+	int ret;
+	unsigned int data;
+	unsigned long delay = info->drv_data->delay;
+
+	if (op == MAX77686_RTC_WRITE)
+		data = 1 << RTC_UDR_SHIFT;
+	else
+		data = 1 << RTC_RBUDR_SHIFT;
+
+	ret = regmap_update_bits(info->rtc_regmap,
+				 info->drv_data->map[REG_RTC_UPDATE0],
+				 data, data);
+	if (ret < 0)
+		dev_err(info->dev, "Fail to write update reg(ret=%d, data=0x%x)\n",
+			ret, data);
+	else {
+		/* Minimum delay required before RTC update. */
+		usleep_range(delay, delay * 2);
+	}
+
+	return ret;
+}
+
+static int max77686_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct max77686_rtc_info *info = dev_get_drvdata(dev);
+	u8 data[RTC_NR_TIME];
+	int ret;
+
+	mutex_lock(&info->lock);
+
+	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
+	if (ret < 0)
+		goto out;
+
+	ret = regmap_bulk_read(info->rtc_regmap,
+			       info->drv_data->map[REG_RTC_SEC],
+			       data, ARRAY_SIZE(data));
+	if (ret < 0) {
+		dev_err(info->dev, "Fail to read time reg(%d)\n", ret);
+		goto out;
+	}
+
+	max77686_rtc_data_to_tm(data, tm, info);
+
+out:
+	mutex_unlock(&info->lock);
+	return ret;
+}
+
+static int max77686_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct max77686_rtc_info *info = dev_get_drvdata(dev);
+	u8 data[RTC_NR_TIME];
+	int ret;
+
+	ret = max77686_rtc_tm_to_data(tm, data, info);
+	if (ret < 0)
+		return ret;
+
+	mutex_lock(&info->lock);
+
+	ret = regmap_bulk_write(info->rtc_regmap,
+				info->drv_data->map[REG_RTC_SEC],
+				data, ARRAY_SIZE(data));
+	if (ret < 0) {
+		dev_err(info->dev, "Fail to write time reg(%d)\n", ret);
+		goto out;
+	}
+
+	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
+
+out:
+	mutex_unlock(&info->lock);
+	return ret;
+}
+
+static int max77686_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct max77686_rtc_info *info = dev_get_drvdata(dev);
+	u8 data[RTC_NR_TIME];
+	unsigned int val;
+	const unsigned int *map = info->drv_data->map;
+	int i, ret;
+
+	mutex_lock(&info->lock);
+
+	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
+	if (ret < 0)
+		goto out;
+
+	ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
+			       data, ARRAY_SIZE(data));
+	if (ret < 0) {
+		dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
+		goto out;
+	}
+
+	max77686_rtc_data_to_tm(data, &alrm->time, info);
+
+	alrm->enabled = 0;
+
+	if (info->drv_data->alarm_enable_reg) {
+		if (map[REG_RTC_AE1] == REG_RTC_NONE) {
+			ret = -EINVAL;
+			dev_err(info->dev,
+				"alarm enable register not set(%d)\n", ret);
+			goto out;
+		}
+
+		ret = regmap_read(info->rtc_regmap, map[REG_RTC_AE1], &val);
+		if (ret < 0) {
+			dev_err(info->dev,
+				"fail to read alarm enable(%d)\n", ret);
+			goto out;
+		}
+
+		if (val)
+			alrm->enabled = 1;
+	} else {
+		for (i = 0; i < ARRAY_SIZE(data); i++) {
+			if (data[i] & ALARM_ENABLE_MASK) {
+				alrm->enabled = 1;
+				break;
+			}
+		}
+	}
+
+	alrm->pending = 0;
+
+	if (info->drv_data->alarm_pending_status_reg == MAX77686_INVALID_REG)
+		goto out;
+
+	ret = regmap_read(info->regmap,
+			  info->drv_data->alarm_pending_status_reg, &val);
+	if (ret < 0) {
+		dev_err(info->dev,
+			"Fail to read alarm pending status reg(%d)\n", ret);
+		goto out;
+	}
+
+	if (val & (1 << 4)) /* RTCA1 */
+		alrm->pending = 1;
+
+out:
+	mutex_unlock(&info->lock);
+	return ret;
+}
+
+static int max77686_rtc_stop_alarm(struct max77686_rtc_info *info)
+{
+	u8 data[RTC_NR_TIME];
+	int ret, i;
+	struct rtc_time tm;
+	const unsigned int *map = info->drv_data->map;
+
+	if (!mutex_is_locked(&info->lock))
+		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
+
+	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
+	if (ret < 0)
+		goto out;
+
+	if (info->drv_data->alarm_enable_reg) {
+		if (map[REG_RTC_AE1] == REG_RTC_NONE) {
+			ret = -EINVAL;
+			dev_err(info->dev,
+				"alarm enable register not set(%d)\n", ret);
+			goto out;
+		}
+
+		ret = regmap_write(info->rtc_regmap, map[REG_RTC_AE1], 0);
+	} else {
+		ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
+				       data, ARRAY_SIZE(data));
+		if (ret < 0) {
+			dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
+			goto out;
+		}
+
+		max77686_rtc_data_to_tm(data, &tm, info);
+
+		for (i = 0; i < ARRAY_SIZE(data); i++)
+			data[i] &= ~ALARM_ENABLE_MASK;
+
+		ret = regmap_bulk_write(info->rtc_regmap, map[REG_ALARM1_SEC],
+					data, ARRAY_SIZE(data));
+	}
+
+	if (ret < 0) {
+		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
+		goto out;
+	}
+
+	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
+out:
+	return ret;
+}
+
+static int max77686_rtc_start_alarm(struct max77686_rtc_info *info)
+{
+	u8 data[RTC_NR_TIME];
+	int ret;
+	struct rtc_time tm;
+	const unsigned int *map = info->drv_data->map;
+
+	if (!mutex_is_locked(&info->lock))
+		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
+
+	ret = max77686_rtc_update(info, MAX77686_RTC_READ);
+	if (ret < 0)
+		goto out;
+
+	if (info->drv_data->alarm_enable_reg) {
+		ret = regmap_write(info->rtc_regmap, map[REG_RTC_AE1],
+				   MAX77802_ALARM_ENABLE_VALUE);
+	} else {
+		ret = regmap_bulk_read(info->rtc_regmap, map[REG_ALARM1_SEC],
+				       data, ARRAY_SIZE(data));
+		if (ret < 0) {
+			dev_err(info->dev, "Fail to read alarm reg(%d)\n", ret);
+			goto out;
+		}
+
+		max77686_rtc_data_to_tm(data, &tm, info);
+
+		data[RTC_SEC] |= (1 << ALARM_ENABLE_SHIFT);
+		data[RTC_MIN] |= (1 << ALARM_ENABLE_SHIFT);
+		data[RTC_HOUR] |= (1 << ALARM_ENABLE_SHIFT);
+		data[RTC_WEEKDAY] &= ~ALARM_ENABLE_MASK;
+		if (data[RTC_MONTH] & 0xf)
+			data[RTC_MONTH] |= (1 << ALARM_ENABLE_SHIFT);
+		if (data[RTC_YEAR] & info->drv_data->mask)
+			data[RTC_YEAR] |= (1 << ALARM_ENABLE_SHIFT);
+		if (data[RTC_DATE] & 0x1f)
+			data[RTC_DATE] |= (1 << ALARM_ENABLE_SHIFT);
+
+		ret = regmap_bulk_write(info->rtc_regmap, map[REG_ALARM1_SEC],
+					data, ARRAY_SIZE(data));
+	}
+
+	if (ret < 0) {
+		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
+		goto out;
+	}
+
+	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
+out:
+	return ret;
+}
+
+static int max77686_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct max77686_rtc_info *info = dev_get_drvdata(dev);
+	u8 data[RTC_NR_TIME];
+	int ret;
+
+	ret = max77686_rtc_tm_to_data(&alrm->time, data, info);
+	if (ret < 0)
+		return ret;
+
+	mutex_lock(&info->lock);
+
+	ret = max77686_rtc_stop_alarm(info);
+	if (ret < 0)
+		goto out;
+
+	ret = regmap_bulk_write(info->rtc_regmap,
+				info->drv_data->map[REG_ALARM1_SEC],
+				data, ARRAY_SIZE(data));
+
+	if (ret < 0) {
+		dev_err(info->dev, "Fail to write alarm reg(%d)\n", ret);
+		goto out;
+	}
+
+	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
+	if (ret < 0)
+		goto out;
+
+	if (alrm->enabled)
+		ret = max77686_rtc_start_alarm(info);
+out:
+	mutex_unlock(&info->lock);
+	return ret;
+}
+
+static int max77686_rtc_alarm_irq_enable(struct device *dev,
+					 unsigned int enabled)
+{
+	struct max77686_rtc_info *info = dev_get_drvdata(dev);
+	int ret;
+
+	mutex_lock(&info->lock);
+	if (enabled)
+		ret = max77686_rtc_start_alarm(info);
+	else
+		ret = max77686_rtc_stop_alarm(info);
+	mutex_unlock(&info->lock);
+
+	return ret;
+}
+
+static irqreturn_t max77686_rtc_alarm_irq(int irq, void *data)
+{
+	struct max77686_rtc_info *info = data;
+
+	dev_dbg(info->dev, "RTC alarm IRQ: %d\n", irq);
+
+	rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
+
+	return IRQ_HANDLED;
+}
+
+static const struct rtc_class_ops max77686_rtc_ops = {
+	.read_time = max77686_rtc_read_time,
+	.set_time = max77686_rtc_set_time,
+	.read_alarm = max77686_rtc_read_alarm,
+	.set_alarm = max77686_rtc_set_alarm,
+	.alarm_irq_enable = max77686_rtc_alarm_irq_enable,
+};
+
+static int max77686_rtc_init_reg(struct max77686_rtc_info *info)
+{
+	u8 data[2];
+	int ret;
+
+	/* Set RTC control register : Binary mode, 24hour mdoe */
+	data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
+	data[1] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
+
+	info->rtc_24hr_mode = 1;
+
+	ret = regmap_bulk_write(info->rtc_regmap,
+				info->drv_data->map[REG_RTC_CONTROLM],
+				data, ARRAY_SIZE(data));
+	if (ret < 0) {
+		dev_err(info->dev, "Fail to write controlm reg(%d)\n", ret);
+		return ret;
+	}
+
+	ret = max77686_rtc_update(info, MAX77686_RTC_WRITE);
+	return ret;
+}
+
+static const struct regmap_config max77686_rtc_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+};
+
+static int max77686_init_rtc_regmap(struct max77686_rtc_info *info)
+{
+	struct device *parent = info->dev->parent;
+	struct i2c_client *parent_i2c = to_i2c_client(parent);
+	int ret;
+
+	if (info->drv_data->rtc_irq_from_platform) {
+		struct platform_device *pdev = to_platform_device(info->dev);
+
+		info->rtc_irq = platform_get_irq(pdev, 0);
+		if (info->rtc_irq < 0) {
+			dev_err(info->dev, "Failed to get rtc interrupts: %d\n",
+				info->rtc_irq);
+			return info->rtc_irq;
+		}
+	} else {
+		info->rtc_irq =  parent_i2c->irq;
+	}
+
+	info->regmap = dev_get_regmap(parent, NULL);
+	if (!info->regmap) {
+		dev_err(info->dev, "Failed to get rtc regmap\n");
+		return -ENODEV;
+	}
+
+	if (info->drv_data->rtc_i2c_addr == MAX77686_INVALID_I2C_ADDR) {
+		info->rtc_regmap = info->regmap;
+		goto add_rtc_irq;
+	}
+
+	info->rtc = i2c_new_dummy(parent_i2c->adapter,
+				  info->drv_data->rtc_i2c_addr);
+	if (!info->rtc) {
+		dev_err(info->dev, "Failed to allocate I2C device for RTC\n");
+		return -ENODEV;
+	}
+
+	info->rtc_regmap = devm_regmap_init_i2c(info->rtc,
+						&max77686_rtc_regmap_config);
+	if (IS_ERR(info->rtc_regmap)) {
+		ret = PTR_ERR(info->rtc_regmap);
+		dev_err(info->dev, "Failed to allocate RTC regmap: %d\n", ret);
+		goto err_unregister_i2c;
+	}
+
+add_rtc_irq:
+	ret = regmap_add_irq_chip(info->rtc_regmap, info->rtc_irq,
+				  IRQF_ONESHOT | IRQF_SHARED,
+				  0, info->drv_data->rtc_irq_chip,
+				  &info->rtc_irq_data);
+	if (ret < 0) {
+		dev_err(info->dev, "Failed to add RTC irq chip: %d\n", ret);
+		goto err_unregister_i2c;
+	}
+
+	return 0;
+
+err_unregister_i2c:
+	if (info->rtc)
+		i2c_unregister_device(info->rtc);
+	return ret;
+}
+
+static int max77686_rtc_probe(struct platform_device *pdev)
+{
+	struct max77686_rtc_info *info;
+	const struct platform_device_id *id = platform_get_device_id(pdev);
+	int ret;
+
+	info = devm_kzalloc(&pdev->dev, sizeof(struct max77686_rtc_info),
+			    GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	mutex_init(&info->lock);
+	info->dev = &pdev->dev;
+	info->drv_data = (const struct max77686_rtc_driver_data *)
+		id->driver_data;
+
+	ret = max77686_init_rtc_regmap(info);
+	if (ret < 0)
+		return ret;
+
+	platform_set_drvdata(pdev, info);
+
+	ret = max77686_rtc_init_reg(info);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Failed to initialize RTC reg:%d\n", ret);
+		goto err_rtc;
+	}
+
+	device_init_wakeup(&pdev->dev, 1);
+
+	info->rtc_dev = devm_rtc_device_register(&pdev->dev, id->name,
+					&max77686_rtc_ops, THIS_MODULE);
+
+	if (IS_ERR(info->rtc_dev)) {
+		ret = PTR_ERR(info->rtc_dev);
+		dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
+		if (ret == 0)
+			ret = -EINVAL;
+		goto err_rtc;
+	}
+
+	info->virq = regmap_irq_get_virq(info->rtc_irq_data,
+					 MAX77686_RTCIRQ_RTCA1);
+	if (info->virq <= 0) {
+		ret = -ENXIO;
+		goto err_rtc;
+	}
+
+	ret = request_threaded_irq(info->virq, NULL, max77686_rtc_alarm_irq, 0,
+				   "rtc-alarm1", info);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
+			info->virq, ret);
+		goto err_rtc;
+	}
+
+	return 0;
+
+err_rtc:
+	regmap_del_irq_chip(info->rtc_irq, info->rtc_irq_data);
+	if (info->rtc)
+		i2c_unregister_device(info->rtc);
+
+	return ret;
+}
+
+static int max77686_rtc_remove(struct platform_device *pdev)
+{
+	struct max77686_rtc_info *info = platform_get_drvdata(pdev);
+
+	free_irq(info->virq, info);
+	regmap_del_irq_chip(info->rtc_irq, info->rtc_irq_data);
+	if (info->rtc)
+		i2c_unregister_device(info->rtc);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int max77686_rtc_suspend(struct device *dev)
+{
+	if (device_may_wakeup(dev)) {
+		struct max77686_rtc_info *info = dev_get_drvdata(dev);
+
+		return enable_irq_wake(info->virq);
+	}
+
+	return 0;
+}
+
+static int max77686_rtc_resume(struct device *dev)
+{
+	if (device_may_wakeup(dev)) {
+		struct max77686_rtc_info *info = dev_get_drvdata(dev);
+
+		return disable_irq_wake(info->virq);
+	}
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(max77686_rtc_pm_ops,
+			 max77686_rtc_suspend, max77686_rtc_resume);
+
+static const struct platform_device_id rtc_id[] = {
+	{ "max77686-rtc", .driver_data = (kernel_ulong_t)&max77686_drv_data, },
+	{ "max77802-rtc", .driver_data = (kernel_ulong_t)&max77802_drv_data, },
+	{ "max77620-rtc", .driver_data = (kernel_ulong_t)&max77620_drv_data, },
+	{},
+};
+MODULE_DEVICE_TABLE(platform, rtc_id);
+
+static struct platform_driver max77686_rtc_driver = {
+	.driver		= {
+		.name	= "max77686-rtc",
+		.pm	= &max77686_rtc_pm_ops,
+	},
+	.probe		= max77686_rtc_probe,
+	.remove		= max77686_rtc_remove,
+	.id_table	= rtc_id,
+};
+
+module_platform_driver(max77686_rtc_driver);
+
+MODULE_DESCRIPTION("Maxim MAX77686 RTC driver");
+MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
+MODULE_LICENSE("GPL");