rtc: palmas: clean-up rtc driver

Clean-up and align the Palmas RTC driver to mainline.
Following are the changes:
- Remove intermediate read/write API and directly use the palmas_*
  APIs.
- Simplify the read-time/set-time/read-alarm and set-alarm
  implementation.
- Avoid duplication of code by using function.

Change-Id: I70a3c65312a21da170a5a0558a3cefd7d8f796bd
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-on: http://git-master/r/266677

1 files changed, 166 insertions, 217 deletions

diff --git a/drivers/rtc/rtc-palmas.c b/drivers/rtc/rtc-palmas.c
index 4a20185511df..ae747543450e 100644
--- a/drivers/rtc/rtc-palmas.c
+++ b/drivers/rtc/rtc-palmas.c
@@ -1,8 +1,13 @@
 /*
- * rtc-palmas.c -- Palmas Real Time Clock interface
+ * rtc-palmas.c -- Palmas Real Time Clock driver.
+
+ * RTC driver for TI Palma series devices like TPS65913,
+ * TPS65914 power management IC.
  *
  * Copyright (c) 2012 - 2013, NVIDIA CORPORATION.  All rights reserved.
+ *
  * Author: Kasoju Mallikarjun <mkasoju@nvidia.com>
+ * Author: Laxman Dewangan <ldewangan@nvidia.com>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
@@ -10,7 +15,7 @@
  *
  * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
  * whether express or implied; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
@@ -19,115 +24,46 @@
  * 02111-1307, USA
  */
 
-#include <linux/kernel.h>
+#include <linux/bcd.h>
 #include <linux/errno.h>
 #include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mfd/palmas.h>
 #include <linux/module.h>
-#include <linux/types.h>
+#include <linux/of.h>
 #include <linux/rtc.h>
-#include <linux/bcd.h>
+#include <linux/types.h>
 #include <linux/platform_device.h>
-#include <linux/interrupt.h>
-#include <linux/mfd/palmas.h>
+#include <linux/pm.h>
 
 struct palmas_rtc {
 	struct rtc_device	*rtc;
-	/* To store the list of enabled interrupts */
-	unsigned int irqstat;
-	unsigned int irq;
+	struct device		*dev;
+	unsigned int		irq;
 };
 
 /* Total number of RTC registers needed to set time*/
-#define NUM_TIME_REGS	(PALMAS_YEARS_REG - PALMAS_SECONDS_REG + 1)
-
-int palmas_rtc_read(struct palmas *palmas, unsigned int reg,
-				unsigned int *dest)
-{
-	unsigned int addr;
-	addr = PALMAS_BASE_TO_REG(PALMAS_RTC_BASE, reg);
-
-	return regmap_read(palmas->regmap[RTC_SLAVE], addr, dest);
-}
-
-int palmas_rtc_write(struct palmas *palmas, unsigned int reg,
-				unsigned int value)
-{
-	unsigned int addr;
-	addr = PALMAS_BASE_TO_REG(PALMAS_RTC_BASE, reg);
-
-	return regmap_write(palmas->regmap[RTC_SLAVE], addr, value);
-}
-
-int palmas_rtc_bulk_read(struct palmas *palmas, unsigned int reg,
-				void *val, size_t val_count)
-{
-	unsigned int addr;
-	addr = PALMAS_BASE_TO_REG(PALMAS_RTC_BASE, reg);
-
-	return regmap_bulk_read(palmas->regmap[RTC_SLAVE], addr,
-		val, val_count);
-}
-
-int palmas_rtc_bulk_write(struct palmas *palmas, unsigned int reg,
-	const void *val, size_t val_count)
-{
-	unsigned int addr;
-	addr = PALMAS_BASE_TO_REG(PALMAS_RTC_BASE, reg);
-
-	return regmap_bulk_write(palmas->regmap[RTC_SLAVE], addr,
-		val, val_count);
-}
-
-int palmas_rtc_update_bits(struct palmas *palmas, unsigned int reg,
-				unsigned int mask, unsigned int val)
-{
-	unsigned int addr;
-	addr = PALMAS_BASE_TO_REG(PALMAS_RTC_BASE, reg);
-
-	return regmap_update_bits(palmas->regmap[RTC_SLAVE], addr, mask, val);
-}
+#define PALMAS_NUM_TIME_REGS	(PALMAS_YEARS_REG - PALMAS_SECONDS_REG + 1)
 
-static int palmas_rtc_alarm_irq_enable(struct device *dev, unsigned enabled)
-{
-	struct palmas *palmas = dev_get_drvdata(dev->parent);
-	u8 val = 0;
-
-	dev_dbg(dev, "%s(): enabled %u\n", __func__, enabled);
-
-	if (enabled)
-		val = PALMAS_RTC_INTERRUPTS_REG_IT_ALARM;
-
-	return palmas_rtc_write(palmas,
-		PALMAS_RTC_INTERRUPTS_REG, val);
-}
-
-/*
- * Gets current palmas RTC time and date parameters.
- *
- * The RTC's time/alarm representation is not what gmtime(3) requires
- * Linux to use:
- *
- *  - Months are 1..12 vs Linux 0-11
- *  - Years are 0..99 vs Linux 1900..N (we assume 21st century)
- */
 static int palmas_rtc_read_time(struct device *dev, struct rtc_time *tm)
 {
-	unsigned char rtc_data[NUM_TIME_REGS];
+	unsigned char rtc_data[PALMAS_NUM_TIME_REGS];
 	struct palmas *palmas = dev_get_drvdata(dev->parent);
 	int ret;
 
 	/* Copy RTC counting registers to static registers or latches */
-	ret = palmas_rtc_update_bits(palmas, PALMAS_RTC_CTRL_REG,
+	ret = palmas_update_bits(palmas, PALMAS_RTC_BASE, PALMAS_RTC_CTRL_REG,
 		PALMAS_RTC_CTRL_REG_GET_TIME, PALMAS_RTC_CTRL_REG_GET_TIME);
 	if (ret < 0) {
-		dev_err(dev, "RTC CTRL reg update failed with err:%d\n", ret);
+		dev_err(dev, "RTC CTRL reg update failed, err: %d\n", ret);
 		return ret;
 	}
 
-	ret = palmas_rtc_bulk_read(palmas, PALMAS_SECONDS_REG,
-		rtc_data, NUM_TIME_REGS);
+	ret = palmas_bulk_read(palmas, PALMAS_RTC_BASE, PALMAS_SECONDS_REG,
+			rtc_data, PALMAS_NUM_TIME_REGS);
 	if (ret < 0) {
-		dev_err(dev, "reading from RTC failed with err:%d\n", ret);
+		dev_err(dev, "RTC_SECONDS reg read failed, err = %d\n", ret);
 		return ret;
 	}
 
@@ -146,7 +82,7 @@ static int palmas_rtc_read_time(struct device *dev, struct rtc_time *tm)
 
 static int palmas_rtc_set_time(struct device *dev, struct rtc_time *tm)
 {
-	unsigned char rtc_data[NUM_TIME_REGS];
+	unsigned char rtc_data[PALMAS_NUM_TIME_REGS];
 	struct palmas *palmas = dev_get_drvdata(dev->parent);
 	int ret;
 
@@ -162,44 +98,50 @@ static int palmas_rtc_set_time(struct device *dev, struct rtc_time *tm)
 		tm->tm_hour, tm->tm_min, tm->tm_sec);
 
 	/* Stop RTC while updating the RTC time registers */
-	ret = palmas_rtc_update_bits(palmas, PALMAS_RTC_CTRL_REG,
+	ret = palmas_update_bits(palmas, PALMAS_RTC_BASE, PALMAS_RTC_CTRL_REG,
 		PALMAS_RTC_CTRL_REG_STOP_RTC, 0);
 	if (ret < 0) {
-		dev_err(dev, "RTC stop failed with err:%d\n", ret);
+		dev_err(dev, "RTC stop failed, err = %d\n", ret);
 		return ret;
 	}
 
-	/* update all the time registers in one shot */
-	ret = palmas_rtc_bulk_write(palmas, PALMAS_SECONDS_REG,
-		rtc_data, NUM_TIME_REGS);
+	ret = palmas_bulk_write(palmas, PALMAS_RTC_BASE, PALMAS_SECONDS_REG,
+		rtc_data, PALMAS_NUM_TIME_REGS);
 	if (ret < 0) {
-		dev_err(dev, "rtc_set_time error %d\n", ret);
+		dev_err(dev, "RTC_SECONDS reg write failed, err = %d\n", ret);
 		return ret;
 	}
 
 	/* Start back RTC */
-	ret = palmas_rtc_update_bits(palmas, PALMAS_RTC_CTRL_REG,
-		PALMAS_RTC_CTRL_REG_STOP_RTC, 1);
+	ret = palmas_update_bits(palmas, PALMAS_RTC_BASE, PALMAS_RTC_CTRL_REG,
+		PALMAS_RTC_CTRL_REG_STOP_RTC, PALMAS_RTC_CTRL_REG_STOP_RTC);
 	if (ret < 0)
-		dev_err(dev, "RTC start failed with err:%d\n", ret);
-
+		dev_err(dev, "RTC start failed, err = %d\n", ret);
 	return ret;
 }
 
-/*
- * Gets current palmas RTC alarm time.
- */
+static int palmas_rtc_alarm_irq_enable(struct device *dev, unsigned enabled)
+{
+	struct palmas *palmas = dev_get_drvdata(dev->parent);
+	u8 val;
+
+	val = enabled ? PALMAS_RTC_INTERRUPTS_REG_IT_ALARM : 0;
+	return palmas_write(palmas, PALMAS_RTC_BASE,
+		PALMAS_RTC_INTERRUPTS_REG, val);
+}
+
 static int palmas_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
 {
-	unsigned char alarm_data[NUM_TIME_REGS];
+	unsigned char alarm_data[PALMAS_NUM_TIME_REGS];
 	u32 int_val;
 	struct palmas *palmas = dev_get_drvdata(dev->parent);
 	int ret;
 
-	ret = palmas_rtc_bulk_read(palmas, PALMAS_ALARM_SECONDS_REG,
-		alarm_data, NUM_TIME_REGS);
+	ret = palmas_bulk_read(palmas, PALMAS_RTC_BASE,
+			PALMAS_ALARM_SECONDS_REG,
+			alarm_data, PALMAS_NUM_TIME_REGS);
 	if (ret < 0) {
-		dev_err(dev, "rtc_read_alarm error %d\n", ret);
+		dev_err(dev, "RTC_ALARM_SECONDS read failed, err = %d\n", ret);
 		return ret;
 	}
 
@@ -214,27 +156,29 @@ static int palmas_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
 		alm->time.tm_year, alm->time.tm_mon, alm->time.tm_mday,
 		alm->time.tm_hour, alm->time.tm_min, alm->time.tm_sec);
 
-	ret = palmas_rtc_read(palmas, PALMAS_RTC_INTERRUPTS_REG,
-		&int_val);
-	if (ret < 0)
+	ret = palmas_read(palmas, PALMAS_RTC_BASE, PALMAS_RTC_INTERRUPTS_REG,
+			&int_val);
+	if (ret < 0) {
+		dev_err(dev, "RTC_INTERRUPTS reg read failed, err = %d\n", ret);
 		return ret;
+	}
 
 	if (int_val & PALMAS_RTC_INTERRUPTS_REG_IT_ALARM)
 		alm->enabled = 1;
-
 	return ret;
 }
 
 static int palmas_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
 {
-	unsigned char alarm_data[NUM_TIME_REGS];
+	unsigned char alarm_data[PALMAS_NUM_TIME_REGS];
 	struct palmas *palmas = dev_get_drvdata(dev->parent);
 	int ret;
 
-	dev_dbg(dev, "%s()\n", __func__);
 	ret = palmas_rtc_alarm_irq_enable(dev, 0);
-	if (ret)
+	if (ret < 0) {
+		dev_err(dev, "Disable RTC alarm failed\n");
 		return ret;
+	}
 
 	alarm_data[0] = bin2bcd(alm->time.tm_sec);
 	alarm_data[1] = bin2bcd(alm->time.tm_min);
@@ -247,49 +191,53 @@ static int palmas_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
 		alm->time.tm_year, alm->time.tm_mon, alm->time.tm_mday,
 		alm->time.tm_hour, alm->time.tm_min, alm->time.tm_sec);
 
-	/* update all the alarm registers in one shot */
-	ret = palmas_rtc_bulk_write(palmas,
-		PALMAS_ALARM_SECONDS_REG, alarm_data, NUM_TIME_REGS);
-	if (ret) {
-		dev_err(dev, "rtc_set_alarm error %d\n", ret);
+	ret = palmas_bulk_write(palmas, PALMAS_RTC_BASE,
+		PALMAS_ALARM_SECONDS_REG, alarm_data, PALMAS_NUM_TIME_REGS);
+	if (ret < 0) {
+		dev_err(dev, "ALARM_SECONDS_REG write failed, err = %d\n", ret);
 		return ret;
 	}
 
 	if (alm->enabled)
 		ret = palmas_rtc_alarm_irq_enable(dev, 1);
-
 	return ret;
 }
 
-static irqreturn_t palmas_rtc_interrupt(int irq, void *rtc)
+static int palmas_clear_interrupts(struct device *dev)
 {
-	struct device *dev = rtc;
-	unsigned long events = 0;
 	struct palmas *palmas = dev_get_drvdata(dev->parent);
-	struct palmas_rtc *palmas_rtc = dev_get_drvdata(dev);
+	unsigned int rtc_reg;
 	int ret;
-	u32 rtc_reg;
 
-	dev_dbg(dev, "RTC ISR\n");
-
-	ret = palmas_rtc_read(palmas, PALMAS_RTC_STATUS_REG,
-		&rtc_reg);
-	if (ret)
-		return IRQ_NONE;
+	ret = palmas_read(palmas, PALMAS_RTC_BASE, PALMAS_RTC_STATUS_REG,
+				&rtc_reg);
+	if (ret < 0) {
+		dev_err(dev, "RTC_STATUS read failed, err = %d\n", ret);
+		return ret;
+	}
 
-	dev_dbg(dev, "RTC ISR status 0x%02x\n", rtc_reg);
+	ret = palmas_write(palmas, PALMAS_RTC_BASE, PALMAS_RTC_STATUS_REG,
+			rtc_reg);
+	if (ret < 0) {
+		dev_err(dev, "RTC_STATUS write failed, err = %d\n", ret);
+		return ret;
+	}
+	return 0;
+}
 
-	if (rtc_reg & PALMAS_RTC_STATUS_REG_ALARM)
-		events = RTC_IRQF | RTC_AF;
+static irqreturn_t palmas_rtc_interrupt(int irq, void *context)
+{
+	struct palmas_rtc *palmas_rtc = context;
+	struct device *dev = palmas_rtc->dev;
+	int ret;
 
-	ret = palmas_rtc_write(palmas, PALMAS_RTC_STATUS_REG,
-		rtc_reg);
-	if (ret)
+	ret = palmas_clear_interrupts(dev);
+	if (ret < 0) {
+		dev_err(dev, "RTC interrupt clear failed, err = %d\n", ret);
 		return IRQ_NONE;
+	}
 
-	/* Notify RTC core on event */
-	rtc_update_irq(palmas_rtc->rtc, 1, events);
-
+	rtc_update_irq(palmas_rtc->rtc, 1, RTC_IRQF | RTC_AF);
 	return IRQ_HANDLED;
 }
 
@@ -303,14 +251,28 @@ static struct rtc_class_ops palmas_rtc_ops = {
 
 static int palmas_rtc_probe(struct platform_device *pdev)
 {
-	struct palmas *palmas = NULL;
+	struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
 	struct palmas_rtc *palmas_rtc = NULL;
 	struct palmas_platform_data *palmas_pdata;
 	struct palmas_rtc_platform_data *rtc_pdata = NULL;
 	int ret;
-	u32 rtc_reg;
+	bool enable_bb_charging = false;
+	bool high_bb_charging;
 
-	palmas = dev_get_drvdata(pdev->dev.parent);
+
+	palmas_pdata = dev_get_platdata(pdev->dev.parent);
+	if (palmas_pdata)
+		rtc_pdata = palmas_pdata->rtc_pdata;
+
+	if (rtc_pdata) {
+		enable_bb_charging = rtc_pdata->backup_battery_chargeable;
+		high_bb_charging = rtc_pdata->backup_battery_charge_high_current;
+	} else if (pdev->dev.of_node) {
+		enable_bb_charging = of_property_read_bool(pdev->dev.of_node,
+					"ti,backup-battery-chargeable");
+		high_bb_charging = of_property_read_bool(pdev->dev.of_node,
+					"ti,backup-battery-charge-high-current");
+	}
 
 	palmas_rtc = devm_kzalloc(&pdev->dev, sizeof(struct palmas_rtc),
 			GFP_KERNEL);
@@ -319,125 +281,106 @@ static int palmas_rtc_probe(struct platform_device *pdev)
 		return -ENOMEM;
 	}
 
-	palmas_pdata = dev_get_platdata(pdev->dev.parent);
-	if (palmas_pdata)
-		rtc_pdata = palmas_pdata->rtc_pdata;
+	/* Clear pending interrupts */
+	ret = palmas_clear_interrupts(&pdev->dev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "clear RTC int failed, err = %d\n", ret);
+		return ret;
+	}
 
 	palmas->rtc = palmas_rtc;
-	if (rtc_pdata && rtc_pdata->backup_battery_chargeable) {
-		int slave;
-		unsigned int addr;
-		int reg = 0;
+	palmas_rtc->dev = &pdev->dev;
+	platform_set_drvdata(pdev, palmas_rtc);
 
-		addr = PALMAS_BASE_TO_REG(PALMAS_PMU_CONTROL_BASE,
-				PALMAS_BACKUP_BATTERY_CTRL);
-		slave = PALMAS_BASE_TO_SLAVE(PALMAS_PMU_CONTROL_BASE);
+	if (enable_bb_charging) {
+		unsigned reg = PALMAS_BACKUP_BATTERY_CTRL_BBS_BBC_LOW_ICHRG;
 
-		if (!rtc_pdata->backup_battery_charge_high_current)
-			reg = PALMAS_BACKUP_BATTERY_CTRL_BBS_BBC_LOW_ICHRG;
+		if (high_bb_charging)
+			reg = 0;
 
-		ret = regmap_update_bits(palmas->regmap[slave], addr,
-				PALMAS_BACKUP_BATTERY_CTRL_BBS_BBC_LOW_ICHRG,
-				reg);
+		ret = palmas_update_bits(palmas, PALMAS_PMU_CONTROL_BASE,
+			PALMAS_BACKUP_BATTERY_CTRL,
+			PALMAS_BACKUP_BATTERY_CTRL_BBS_BBC_LOW_ICHRG, reg);
 		if (ret < 0) {
 			dev_err(&pdev->dev,
-				"Battery backup control failed, e %d\n", ret);
+				"BACKUP_BATTERY_CTRL update failed, %d\n", ret);
 			return ret;
-		};
+		}
 
-		ret = regmap_update_bits(palmas->regmap[slave], addr,
-				PALMAS_BACKUP_BATTERY_CTRL_BB_CHG_EN,
-				PALMAS_BACKUP_BATTERY_CTRL_BB_CHG_EN);
+		ret = palmas_update_bits(palmas, PALMAS_PMU_CONTROL_BASE,
+			PALMAS_BACKUP_BATTERY_CTRL,
+			PALMAS_BACKUP_BATTERY_CTRL_BB_CHG_EN,
+			PALMAS_BACKUP_BATTERY_CTRL_BB_CHG_EN);
 		if (ret < 0) {
 			dev_err(&pdev->dev,
-				"Battery backup charging enable failed, e %d\n",
-				ret);
+				"BACKUP_BATTERY_CTRL update failed, %d\n", ret);
 			return ret;
 		}
 	}
 
-	ret = palmas_rtc_write(palmas, PALMAS_RTC_INTERRUPTS_REG, 0);
+	ret = palmas_write(palmas, PALMAS_RTC_BASE,
+				PALMAS_RTC_INTERRUPTS_REG, 0);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "RTC_INTERRUPTS_REG write failed: %d\n",
 				ret);
 		return ret;
 	}
 
-	/* Clear pending interrupts */
-	ret = palmas_rtc_read(palmas, PALMAS_RTC_STATUS_REG,
-		&rtc_reg);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "rtc_read_status error %d\n", ret);
-		return ret;
-	}
-
-	ret = palmas_rtc_write(palmas, PALMAS_RTC_STATUS_REG,
-		rtc_reg);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "rtc_clear_interupt error %d\n", ret);
-		return ret;
-	}
-
-	dev_dbg(&pdev->dev, "Enabling palmas-RTC.\n");
-	rtc_reg = PALMAS_RTC_CTRL_REG_STOP_RTC;
-	ret = palmas_rtc_write(palmas, PALMAS_RTC_CTRL_REG,
-		rtc_reg);
+	/* Start RTC */
+	ret = palmas_update_bits(palmas, PALMAS_RTC_BASE, PALMAS_RTC_CTRL_REG,
+			PALMAS_RTC_CTRL_REG_STOP_RTC,
+			PALMAS_RTC_CTRL_REG_STOP_RTC);
 	if (ret < 0) {
-		dev_err(&pdev->dev, "rtc_enable error %d\n", ret);
+		dev_err(&pdev->dev, "RTC_CTRL write failed, err = %d\n", ret);
 		return ret;
 	}
 
 	palmas_rtc->irq = palmas_irq_get_virq(palmas, PALMAS_RTC_ALARM_IRQ);
 	dev_dbg(&pdev->dev, "RTC interrupt %d\n", palmas_rtc->irq);
-	ret = request_threaded_irq(palmas_rtc->irq, NULL,
-		palmas_rtc_interrupt, IRQF_TRIGGER_LOW | IRQF_ONESHOT |
-		IRQF_EARLY_RESUME,
-		"palmas-rtc", &pdev->dev);
-	if (ret < 0) {
-		dev_err(&pdev->dev, "IRQ is not free.\n");
-		return ret;
-	}
-	device_init_wakeup(&pdev->dev, 1);
-	platform_set_drvdata(pdev, palmas_rtc);
 
+	device_init_wakeup(&pdev->dev, 1);
 	palmas_rtc->rtc = rtc_device_register(pdev->name, &pdev->dev,
 		&palmas_rtc_ops, THIS_MODULE);
 	if (IS_ERR(palmas_rtc->rtc)) {
 		ret = PTR_ERR(palmas_rtc->rtc);
-		free_irq(palmas_rtc->irq, &pdev->dev);
-		dev_err(&pdev->dev, "RTC device register: err %d\n", ret);
+		dev_err(&pdev->dev, "RTC register failed, err = %d\n", ret);
+		return ret;
+	}
+
+	ret = request_threaded_irq(palmas_rtc->irq, NULL,
+			palmas_rtc_interrupt,
+			IRQF_TRIGGER_LOW | IRQF_ONESHOT |
+			IRQF_EARLY_RESUME,
+			dev_name(&pdev->dev), palmas_rtc);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "IRQ request failed, err = %d\n", ret);
+		rtc_device_unregister(palmas_rtc->rtc);
 		return ret;
 	}
 
 	return 0;
 }
 
-/*
- * Disable all palmas RTC module interrupts.
- * Sets status flag to free.
- */
 static int palmas_rtc_remove(struct platform_device *pdev)
 {
-	/* leave rtc running, but disable irqs */
-	struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
+	struct palmas_rtc *palmas_rtc = platform_get_drvdata(pdev);
 
-	palmas_rtc_alarm_irq_enable(&palmas->rtc->rtc->dev, 0);
-	free_irq(palmas->irq, &pdev->dev);
-	rtc_device_unregister(palmas->rtc->rtc);
+	palmas_rtc_alarm_irq_enable(&pdev->dev, 0);
+	free_irq(palmas_rtc->irq, palmas_rtc);
+	rtc_device_unregister(palmas_rtc->rtc);
 	return 0;
 }
 
 #ifdef CONFIG_PM_SLEEP
 static int palmas_rtc_suspend(struct device *dev)
 {
-	struct platform_device *pdev = to_platform_device(dev);
-	struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
+	struct palmas_rtc *palmas_rtc = dev_get_drvdata(dev);
 
 	if (device_may_wakeup(dev)) {
 		int ret;
 		struct rtc_wkalrm alm;
 
-		enable_irq_wake(palmas->rtc->irq);
+		enable_irq_wake(palmas_rtc->irq);
 		ret = palmas_rtc_read_alarm(dev, &alm);
 		if (!ret)
 			dev_info(dev, "%s() alrm %d time %d %d %d %d %d %d\n",
@@ -452,14 +395,13 @@ static int palmas_rtc_suspend(struct device *dev)
 
 static int palmas_rtc_resume(struct device *dev)
 {
-	struct platform_device *pdev = to_platform_device(dev);
-	struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
+	struct palmas_rtc *palmas_rtc = dev_get_drvdata(dev);
 
 	if (device_may_wakeup(dev)) {
 		struct rtc_time tm;
 		int ret;
 
-		disable_irq_wake(palmas->rtc->irq);
+		disable_irq_wake(palmas_rtc->irq);
 		ret = palmas_rtc_read_time(dev, &tm);
 		if (!ret)
 			dev_info(dev, "%s() %d %d %d %d %d %d\n",
@@ -469,15 +411,18 @@ static int palmas_rtc_resume(struct device *dev)
 
 	return 0;
 }
+#endif
 
 static const struct dev_pm_ops palmas_rtc_pm_ops = {
-	.suspend	= palmas_rtc_suspend,
-	.resume		= palmas_rtc_resume,
+	SET_SYSTEM_SLEEP_PM_OPS(palmas_rtc_suspend, palmas_rtc_resume)
 };
 
-#define DEV_PM_OPS     (&palmas_rtc_pm_ops)
-#else
-#define DEV_PM_OPS     NULL
+#ifdef CONFIG_OF
+static struct of_device_id of_palmas_rtc_match[] = {
+	{ .compatible = "ti,palmas-rtc"},
+	{ },
+};
+MODULE_DEVICE_TABLE(of, of_palmas_rtc_match);
 #endif
 
 static struct platform_driver palmas_rtc_driver = {
@@ -486,11 +431,15 @@ static struct platform_driver palmas_rtc_driver = {
 	.driver		= {
 		.owner	= THIS_MODULE,
 		.name	= "palmas-rtc",
-		.pm	= DEV_PM_OPS,
+		.pm	= &palmas_rtc_pm_ops,
+		.of_match_table = of_match_ptr(of_palmas_rtc_match),
 	},
 };
 
 module_platform_driver(palmas_rtc_driver);
+
 MODULE_ALIAS("platform:palmas_rtc");
+MODULE_DESCRIPTION("TI PALMAS series RTC driver");
 MODULE_AUTHOR("Kasoju Mallikarjun <mkasoju@nvidia.com>");
+MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
 MODULE_LICENSE("GPL v2");