rtc: max77663: Add MAX77663 RTC driver

Add RTC driver for Maxim PMU MAX77663.

Bug 849360

Change-Id: Ia7c910a852527f6a7bf5d2622cb1f76fd72222cd
Signed-off-by: Jin Park <jinyoungp@nvidia.com>
Reviewed-on: http://git-master/r/49584
Reviewed-by: Laxman Dewangan <ldewangan@nvidia.com>

3 files changed, 573 insertions, 0 deletions

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index a05202a015d2..4c82d428515e 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -223,6 +223,16 @@ config RTC_DRV_MAX8907C
 	  This driver can also be built as a module. If so, the module
 	  will be called rtc-max8907c.
 
+config RTC_DRV_MAX77663
+	tristate "Maxim MAX77663"
+	depends on MFD_MAX77663
+	help
+	  If you say yes here you will get support for the
+	  RTC of Maxim MAX77663 PMIC.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called rtc-max77663.
+
 config RTC_DRV_RS5C372
 	tristate "Ricoh R2025S/D, RS5C372A/B, RV5C386, RV5C387A"
 	help
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 20a2b4f15973..aef7a660c195 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -63,6 +63,7 @@ obj-$(CONFIG_RTC_DRV_MAX6900)	+= rtc-max6900.o
 obj-$(CONFIG_RTC_DRV_MAX8925)	+= rtc-max8925.o
 obj-$(CONFIG_RTC_DRV_MAX8907C)	+= rtc-max8907c.o
 obj-$(CONFIG_RTC_DRV_MAX6902)	+= rtc-max6902.o
+obj-$(CONFIG_RTC_DRV_MAX77663)	+= rtc-max77663.o
 obj-$(CONFIG_RTC_DRV_MC13783)	+= rtc-mc13783.o
 obj-$(CONFIG_RTC_DRV_MSM6242)	+= rtc-msm6242.o
 obj-$(CONFIG_RTC_DRV_MPC5121)	+= rtc-mpc5121.o
diff --git a/drivers/rtc/rtc-max77663.c b/drivers/rtc/rtc-max77663.c
new file mode 100644
index 000000000000..f0bcd83624c0
--- /dev/null
+++ b/drivers/rtc/rtc-max77663.c
@@ -0,0 +1,562 @@
+/*
+ * drivers/rtc/rtc-max77663.c
+ * Max77663 RTC driver
+ *
+ * Copyright 2011 Maxim Integrated Products, Inc.
+ * Copyright (C) 2011 NVIDIA Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ */
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/rtc.h>
+#include <linux/mfd/max77663-core.h>
+
+/* Registers */
+#define MAX77663_RTC_IRQ		0x00
+#define MAX77663_RTC_IRQ_MASK		0x01
+#define MAX77663_RTC_CTRL_MODE		0x02
+#define MAX77663_RTC_CTRL		0x03
+#define MAX77663_RTC_UPDATE0		0x04
+#define MAX77663_RTC_UPDATE1		0x05
+#define MAX77663_RTC_SEC		0x07
+#define MAX77663_RTC_MIN		0x08
+#define MAX77663_RTC_HOUR		0x09
+#define MAX77663_RTC_WEEKDAY		0x0A
+#define MAX77663_RTC_MONTH		0x0B
+#define MAX77663_RTC_YEAR		0x0C
+#define MAX77663_RTC_MONTHDAY		0x0D
+#define MAX77663_RTC_ALARM_SEC1		0x0E
+#define MAX77663_RTC_ALARM_MIN1		0x0F
+#define MAX77663_RTC_ALARM_HOUR1	0x10
+#define MAX77663_RTC_ALARM_WEEKDAY1	0x11
+#define MAX77663_RTC_ALARM_MONTH1	0x12
+#define MAX77663_RTC_ALARM_YEAR1	0x13
+#define MAX77663_RTC_ALARM_MONTHDAY1	0x14
+
+#define RTC_IRQ_60SEC_MASK		(1 << 0)
+#define RTC_IRQ_ALARM1_MASK		(1 << 1)
+#define RTC_IRQ_ALARM2_MASK		(1 << 2)
+#define RTC_IRQ_SMPL_MASK		(1 << 3)
+#define RTC_IRQ_1SEC_MASK		(1 << 4)
+#define RTC_IRQ_MASK			0x1F
+
+#define BCD_MODE_MASK			(1 << 0)
+#define HR_MODE_MASK			(1 << 1)
+
+#define WB_UPDATE_MASK			(1 << 0)
+#define FLAG_AUTO_CLEAR_MASK		(1 << 1)
+#define FREEZE_SEC_MASK			(1 << 2)
+#define RTC_WAKE_MASK			(1 << 3)
+#define RB_UPDATE_MASK			(1 << 4)
+
+#define WB_UPDATE_FLAG_MASK		(1 << 0)
+#define RB_UPDATE_FLAG_MASK		(1 << 1)
+
+#define SEC_MASK			0x7F
+#define MIN_MASK			0x7F
+#define HOUR_MASK			0x3F
+#define WEEKDAY_MASK			0x7F
+#define MONTH_MASK			0x1F
+#define YEAR_MASK			0xFF
+#define MONTHDAY_MASK			0x3F
+
+#define ALARM_EN_MASK			0x80
+#define ALARM_EN_SHIFT			7
+
+#define RTC_UPDATE_RETRIES		20
+#define RTC_YEAR_BASE			100
+#define RTC_YEAR_MAX			99
+
+enum {
+	RTC_SEC,
+	RTC_MIN,
+	RTC_HOUR,
+	RTC_WEEKDAY,
+	RTC_MONTH,
+	RTC_YEAR,
+	RTC_MONTHDAY,
+	RTC_NR
+};
+
+struct max77663_rtc {
+	struct rtc_device *rtc;
+	struct device *dev;
+
+	struct mutex io_lock;
+	int irq;
+	u8 irq_mask;
+};
+
+static inline struct device *_to_parent(struct max77663_rtc *rtc)
+{
+	return rtc->dev->parent;
+}
+
+static inline int max77663_rtc_update_buffer(struct max77663_rtc *rtc,
+					     int write)
+{
+	struct device *parent = _to_parent(rtc);
+	int retries = RTC_UPDATE_RETRIES;
+	u8 val = FLAG_AUTO_CLEAR_MASK | RTC_WAKE_MASK | RB_UPDATE_MASK;
+	u8 flag_mask = RB_UPDATE_FLAG_MASK;
+	int ret;
+
+	if (write) {
+		val = FLAG_AUTO_CLEAR_MASK | RTC_WAKE_MASK | WB_UPDATE_MASK;
+		flag_mask = WB_UPDATE_FLAG_MASK;
+	}
+
+	dev_dbg(rtc->dev, "rtc_update_buffer: write=%d, addr=0x%x, val=0x%x\n",
+		write, MAX77663_RTC_UPDATE0, val);
+	ret = max77663_write(parent, MAX77663_RTC_UPDATE0, &val, 1, 1);
+	if (ret < 0) {
+		dev_err(rtc->dev, "rtc_update_buffer: "
+			"Failed to get rtc update0\n");
+		return ret;
+	}
+
+	do {
+		ret = max77663_read(parent, MAX77663_RTC_UPDATE1, &val, 1, 1);
+		schedule_timeout_uninterruptible(msecs_to_jiffies(1));
+	} while (!ret && retries-- && !(val & flag_mask));
+
+	if (ret < 0) {
+		dev_err(rtc->dev,
+			"rtc_update_buffer: Failed to get rtc update1\n");
+		return ret;
+	}
+
+	if (retries <= 0) {
+		dev_err(rtc->dev, "rtc_update_buffer: "
+			"Timeout waiting for buffer update\n");
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+static inline int max77663_rtc_write(struct max77663_rtc *rtc, u8 addr,
+				     void *values, u32 len, int update_buffer)
+{
+	struct device *parent = _to_parent(rtc);
+	int ret;
+
+	mutex_lock(&rtc->io_lock);
+
+	dev_dbg(rtc->dev, "rtc_write: addr=0x%x, values=0x%x, len=%u, "
+		"update_buffer=%d\n",
+		addr, *((u8 *)values), len, update_buffer);
+	ret = max77663_write(parent, addr, values, len, 1);
+	if (ret < 0)
+		goto out;
+
+	if (update_buffer)
+		ret = max77663_rtc_update_buffer(rtc, 1);
+
+out:
+	mutex_unlock(&rtc->io_lock);
+	return ret;
+}
+
+static inline int max77663_rtc_read(struct max77663_rtc *rtc, u8 addr,
+				    void *values, u32 len, int update_buffer)
+{
+	struct device *parent = _to_parent(rtc);
+	int ret;
+
+	mutex_lock(&rtc->io_lock);
+
+	if (update_buffer) {
+		ret = max77663_rtc_update_buffer(rtc, 0);
+		if (ret < 0)
+			goto out;
+	}
+
+	ret = max77663_read(parent, addr, values, len, 1);
+	dev_dbg(rtc->dev, "rtc_read: addr=0x%x, values=0x%x, len=%u, "
+		"update_buffer=%d\n",
+		addr, *((u8 *)values), len, update_buffer);
+
+out:
+	mutex_unlock(&rtc->io_lock);
+	return ret;
+}
+
+static inline int max77663_rtc_reg_to_tm(struct max77663_rtc *rtc, u8 *buf,
+					 struct rtc_time *tm)
+{
+	int wday = buf[RTC_WEEKDAY] & WEEKDAY_MASK;
+
+	if (unlikely(!wday)) {
+		dev_err(rtc->dev,
+			"rtc_reg_to_tm: Invalid day of week, %d\n", wday);
+		return -EINVAL;
+	}
+
+	tm->tm_sec = (int)(buf[RTC_SEC] & SEC_MASK);
+	tm->tm_min = (int)(buf[RTC_MIN] & MIN_MASK);
+	tm->tm_hour = (int)(buf[RTC_HOUR] & HOUR_MASK);
+	tm->tm_mday = (int)(buf[RTC_MONTHDAY] & MONTHDAY_MASK);
+	tm->tm_mon = (int)(buf[RTC_MONTH] & MONTH_MASK) - 1;
+	tm->tm_year = (int)(buf[RTC_YEAR] & YEAR_MASK) + RTC_YEAR_BASE;
+	tm->tm_wday = ffs(wday);
+
+	dev_dbg(rtc->dev, "rtc_reg_to_tm: buf sec=%u, min=%u, hour=%u, "
+		"mday=%u, month=%u, year=%u, wday=%u\n",
+		buf[RTC_SEC] & SEC_MASK, buf[RTC_MIN] & MIN_MASK,
+		buf[RTC_HOUR] & HOUR_MASK, buf[RTC_MONTHDAY] & MONTHDAY_MASK,
+		buf[RTC_MONTH] & MONTH_MASK, buf[RTC_YEAR] & YEAR_MASK,
+		buf[RTC_WEEKDAY] & WEEKDAY_MASK);
+	dev_dbg(rtc->dev, "rtc_reg_to_tm: tm_sec=%d, tm_min=%d, tm_hour=%d, "
+		"tm_mday=%d, tm_mon=%d, tm_year=%d, tm_wday=%d\n",
+		tm->tm_sec, tm->tm_min, tm->tm_hour, tm->tm_mday, tm->tm_mon,
+		tm->tm_year, tm->tm_wday);
+
+	return 0;
+}
+
+static inline int max77663_rtc_tm_to_reg(struct max77663_rtc *rtc, u8 *buf,
+					 struct rtc_time *tm, int alarm)
+{
+	u8 alarm_mask = alarm ? ALARM_EN_MASK : 0;
+
+	if (unlikely((tm->tm_year < RTC_YEAR_BASE) ||
+			(tm->tm_year > RTC_YEAR_BASE + RTC_YEAR_MAX))) {
+		dev_err(rtc->dev,
+			"rtc_tm_to_reg: Invalid year, %d\n", tm->tm_year);
+		return -EINVAL;
+	}
+
+	buf[RTC_SEC] = tm->tm_sec | alarm_mask;
+	buf[RTC_MIN] = tm->tm_min | alarm_mask;
+	buf[RTC_HOUR] = tm->tm_hour | alarm_mask;
+	buf[RTC_MONTHDAY] = tm->tm_mday | alarm_mask;
+	buf[RTC_MONTH] = (tm->tm_mon + 1) | alarm_mask;
+	buf[RTC_YEAR] = (tm->tm_year - RTC_YEAR_BASE) | alarm_mask;
+	buf[RTC_WEEKDAY] = (1 << tm->tm_wday) | alarm_mask;
+
+	dev_dbg(rtc->dev, "rtc_tm_to_reg: tm_sec=%d, tm_min=%d, tm_hour=%d, "
+		"tm_mday=%d, tm_mon=%d, tm_year=%d, tm_wday=%d, alarm=%d\n",
+		tm->tm_sec, tm->tm_min, tm->tm_hour, tm->tm_mday, tm->tm_mon,
+		tm->tm_year, tm->tm_wday, alarm);
+	dev_dbg(rtc->dev, "rtc_tm_to_reg: buf sec=%u, min=%u, hour=%u, "
+		"mday=%u, month=%u, year=%u, wday=%u\n",
+		buf[RTC_SEC] & SEC_MASK, buf[RTC_MIN] & MIN_MASK,
+		buf[RTC_HOUR] & HOUR_MASK, buf[RTC_MONTHDAY] & MONTHDAY_MASK,
+		buf[RTC_MONTH] & MONTH_MASK, buf[RTC_YEAR] & YEAR_MASK,
+		buf[RTC_WEEKDAY] & WEEKDAY_MASK);
+
+	return 0;
+}
+
+static irqreturn_t max77663_rtc_irq(int irq, void *data)
+{
+	struct max77663_rtc *rtc = (struct max77663_rtc *)data;
+	u8 val = 0;
+	int ret;
+
+	ret = max77663_rtc_read(rtc, MAX77663_RTC_IRQ, &val, 1, 0);
+	if (ret < 0)
+		dev_err(rtc->dev, "rtc_irq: Failed to get rtc irq status\n");
+
+	if (val & RTC_IRQ_ALARM1_MASK)
+		rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);
+
+	if (val & RTC_IRQ_1SEC_MASK)
+		rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_UF);
+
+	return IRQ_HANDLED;
+}
+
+static int max77663_rtc_alarm_irq_enable(struct device *dev,
+					 unsigned int enabled)
+{
+	struct max77663_rtc *rtc = dev_get_drvdata(dev);
+	struct device *parent = _to_parent(rtc);
+	u8 val = 0;
+	int ret = 0;
+
+	if (rtc->irq < 0)
+		return -ENXIO;
+
+	mutex_lock(&rtc->io_lock);
+	if (enabled)
+		val = rtc->irq_mask & ~RTC_IRQ_ALARM1_MASK;
+	else
+		val = rtc->irq_mask | RTC_IRQ_ALARM1_MASK;
+
+	if (val != rtc->irq_mask) {
+		ret = max77663_write(parent, MAX77663_RTC_IRQ_MASK, &val, 1, 1);
+		if (ret < 0) {
+			dev_err(rtc->dev, "rtc_alarm_irq_enable: "
+				"Failed to set rtc irq mask\n");
+			mutex_unlock(&rtc->io_lock);
+			return ret;
+		}
+
+		rtc->irq_mask = val;
+	}
+	mutex_unlock(&rtc->io_lock);
+
+	return 0;
+}
+
+static int max77663_rtc_update_irq_enable(struct device *dev,
+					  unsigned int enabled)
+{
+	struct max77663_rtc *rtc = dev_get_drvdata(dev);
+	struct device *parent = _to_parent(rtc);
+	u8 val = 0;
+	int ret = 0;
+
+	if (rtc->irq < 0)
+		return -ENXIO;
+
+	mutex_lock(&rtc->io_lock);
+	if (enabled)
+		val = rtc->irq_mask & ~RTC_IRQ_1SEC_MASK;
+	else
+		val = rtc->irq_mask | RTC_IRQ_1SEC_MASK;
+
+	if (val != rtc->irq_mask) {
+		ret = max77663_write(parent, MAX77663_RTC_IRQ_MASK, &val, 1, 1);
+		if (ret < 0) {
+			dev_err(rtc->dev, "rtc_update_irq_enable: "
+				"Failed to set rtc irq mask\n");
+			mutex_unlock(&rtc->io_lock);
+			return ret;
+		}
+
+		rtc->irq_mask = val;
+	}
+	mutex_unlock(&rtc->io_lock);
+
+	return 0;
+}
+
+static int max77663_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct max77663_rtc *rtc = dev_get_drvdata(dev);
+	u8 buf[RTC_NR];
+	int ret;
+
+	ret = max77663_rtc_read(rtc, MAX77663_RTC_SEC, buf, sizeof(buf), 1);
+	if (ret < 0) {
+		dev_err(rtc->dev, "rtc_read_time: Failed to read rtc time\n");
+		return ret;
+	}
+
+	return max77663_rtc_reg_to_tm(rtc, buf, tm);
+}
+
+static int max77663_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct max77663_rtc *rtc = dev_get_drvdata(dev);
+	u8 buf[RTC_NR];
+	int ret;
+
+	ret = max77663_rtc_tm_to_reg(rtc, buf, tm, 0);
+	if (ret < 0) {
+		dev_err(rtc->dev, "rtc_set_time: "
+			"Failed to convert time format into register format\n");
+		return ret;
+	}
+
+	return max77663_rtc_write(rtc, MAX77663_RTC_SEC, buf, sizeof(buf), 1);
+}
+
+static int max77663_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct max77663_rtc *rtc = dev_get_drvdata(dev);
+	u8 buf[RTC_NR];
+	int ret;
+
+	ret = max77663_rtc_read(rtc, MAX77663_RTC_ALARM_SEC1, buf, sizeof(buf),
+				1);
+	if (ret < 0) {
+		dev_err(rtc->dev,
+			"rtc_read_alarm: Failed to read rtc alarm time\n");
+		return ret;
+	}
+
+	ret = max77663_rtc_reg_to_tm(rtc, buf, &alrm->time);
+	if (ret < 0) {
+		dev_err(rtc->dev, "rtc_read_alarm: "
+			"Failed to convert register format into time format\n");
+		return ret;
+	}
+
+	if (rtc->irq_mask & RTC_IRQ_ALARM1_MASK)
+		alrm->enabled = 1;
+	else
+		alrm->enabled = 0;
+
+	return 0;
+}
+
+static int max77663_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct max77663_rtc *rtc = dev_get_drvdata(dev);
+	u8 buf[RTC_NR];
+	int ret;
+
+	ret = max77663_rtc_tm_to_reg(rtc, buf, &alrm->time, 1);
+	if (ret < 0) {
+		dev_err(rtc->dev, "rtc_set_alarm: "
+			"Failed to convert time format into register format\n");
+		return ret;
+	}
+
+	ret = max77663_rtc_write(rtc, MAX77663_RTC_ALARM_SEC1, buf, sizeof(buf),
+				 1);
+	if (ret < 0) {
+		dev_err(rtc->dev,
+			"rtc_set_alarm: Failed to write rtc alarm time\n");
+		return ret;
+	}
+
+	ret = max77663_rtc_alarm_irq_enable(dev, alrm->enabled);
+	if (ret < 0) {
+		dev_err(rtc->dev,
+			"rtc_set_alarm: Failed to set rtc alarm irq\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct rtc_class_ops max77663_rtc_ops = {
+	.read_time = max77663_rtc_read_time,
+	.set_time = max77663_rtc_set_time,
+	.read_alarm = max77663_rtc_read_alarm,
+	.set_alarm = max77663_rtc_set_alarm,
+	.alarm_irq_enable = max77663_rtc_alarm_irq_enable,
+	.update_irq_enable = max77663_rtc_update_irq_enable,
+};
+
+static int max77663_rtc_preinit(struct max77663_rtc *rtc)
+{
+	u8 val;
+	int ret;
+
+	/* Mask all interrupts */
+	rtc->irq_mask = RTC_IRQ_MASK;
+	ret = max77663_rtc_write(rtc, MAX77663_RTC_IRQ_MASK, &rtc->irq_mask, 1,
+				 0);
+	if (ret < 0) {
+		dev_err(rtc->dev, "preinit: Failed to set rtc irq mask\n");
+		return ret;
+	}
+
+	/* Configure Binary mode and 24hour mode */
+	val = HR_MODE_MASK;
+	ret = max77663_rtc_write(rtc, MAX77663_RTC_CTRL, &val, 1, 0);
+	if (ret < 0) {
+		dev_err(rtc->dev, "preinit: Failed to set rtc control\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int max77663_rtc_probe(struct platform_device *pdev)
+{
+	struct max77663_platform_data *parent_pdata =
+						pdev->dev.parent->platform_data;
+	static struct max77663_rtc *rtc;
+	int ret = 0;
+
+	rtc = kzalloc(sizeof(struct max77663_rtc), GFP_KERNEL);
+	if (!rtc) {
+		dev_err(&pdev->dev, "probe: kzalloc() failed\n");
+		return -ENOMEM;
+	}
+
+	dev_set_drvdata(&pdev->dev, rtc);
+	rtc->dev = &pdev->dev;
+	mutex_init(&rtc->io_lock);
+
+	ret = max77663_rtc_preinit(rtc);
+	if (ret) {
+		dev_err(&pdev->dev, "probe: Failed to rtc preinit\n");
+		goto out_kfree;
+	}
+
+	rtc->rtc = rtc_device_register("max77663-rtc", &pdev->dev,
+				       &max77663_rtc_ops, THIS_MODULE);
+	if (IS_ERR_OR_NULL(rtc->rtc)) {
+		dev_err(&pdev->dev, "probe: Failed to register rtc\n");
+		ret = PTR_ERR(rtc->rtc);
+		goto out_kfree;
+	}
+
+	if (parent_pdata->irq_base < 0)
+		goto out;
+
+	rtc->irq = parent_pdata->irq_base + MAX77663_IRQ_RTC;
+	ret = request_threaded_irq(rtc->irq, NULL, max77663_rtc_irq,
+				   IRQF_ONESHOT, "max77663-rtc", rtc);
+	if (ret < 0) {
+		dev_err(rtc->dev, "probe: Failed to request irq %d\n",
+			rtc->irq);
+		rtc->irq = -1;
+	} else {
+		device_init_wakeup(rtc->dev, 1);
+		enable_irq_wake(rtc->irq);
+	}
+
+	return 0;
+
+out_kfree:
+	mutex_destroy(&rtc->io_lock);
+	kfree(rtc->rtc);
+out:
+	return ret;
+}
+
+static int __devexit max77663_rtc_remove(struct platform_device *pdev)
+{
+	struct max77663_rtc *rtc = dev_get_drvdata(&pdev->dev);
+
+	if (rtc->irq != -1)
+		free_irq(rtc->irq, rtc);
+
+	rtc_device_unregister(rtc->rtc);
+	mutex_destroy(&rtc->io_lock);
+	kfree(rtc);
+
+	return 0;
+}
+
+static struct platform_driver max77663_rtc_driver = {
+	.probe = max77663_rtc_probe,
+	.remove = __devexit_p(max77663_rtc_remove),
+	.driver = {
+		   .name = "max77663-rtc",
+		   .owner = THIS_MODULE,
+	},
+};
+
+static int __init max77663_rtc_init(void)
+{
+	return platform_driver_register(&max77663_rtc_driver);
+}
+module_init(max77663_rtc_init);
+
+static void __exit max77663_rtc_exit(void)
+{
+	platform_driver_unregister(&max77663_rtc_driver);
+}
+module_exit(max77663_rtc_exit);
+
+MODULE_DESCRIPTION("max77663 RTC driver");
+MODULE_LICENSE("GPL v2");
+MODULE_VERSION("1.0");