Patchwork rtc: add RTC driver for TPS80031/TPS80032

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Submitter Laxman Dewangan
Date Dec. 24, 2012, 9:34 a.m.
Message ID <1356341680-29644-1-git-send-email-ldewangan@nvidia.com>
Download mbox | patch
Permalink /patch/208041/
State New
Headers show

Comments

Laxman Dewangan - Dec. 24, 2012, 9:34 a.m.
Add an RTC driver for TPS80031/TPS80032 chips by TI.
This driver supports:
- Setting and getting time and date.
- Setting and reading alarm time.
- Alarm and interrupt functionlity.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
---
 drivers/rtc/Kconfig        |    8 +
 drivers/rtc/Makefile       |    1 +
 drivers/rtc/rtc-tps80031.c |  363 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 372 insertions(+), 0 deletions(-)
 create mode 100644 drivers/rtc/rtc-tps80031.c
Devendra Naga - Dec. 24, 2012, 10:02 a.m.
Hello,

On Mon, Dec 24, 2012 at 3:04 PM, Laxman Dewangan <ldewangan@nvidia.com> wrote:
> Add an RTC driver for TPS80031/TPS80032 chips by TI.
> This driver supports:
> - Setting and getting time and date.
> - Setting and reading alarm time.
> - Alarm and interrupt functionlity.
>

The patch looks ok, but just some minor comments below :).

> Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
> ---

[snip]

> +
> +static int tps80031_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
> +{
> +       struct rtc_time tm;
> +       unsigned long seconds;
> +       u8 buff[TPS80031_RTC_ALARM_NUM_REGS];
> +       int ret;
> +       unsigned long epoch_start;
> +
> +       rtc_tm_to_time(&alrm->time, &seconds);
> +       ret = tps80031_rtc_read_time(dev, &tm);
> +       if (ret < 0) {
> +               dev_err(dev, "Error in getting current time, err = %d\n", ret);
> +               return ret;
> +       }
> +       rtc_tm_to_time(&tm, &epoch_start);

> +
> +       if (alrm->enabled && (seconds < epoch_start)) {

its better to have this check in the core itself rather duplicating
everywhere, but i think the core already have this check, will you
please check ?

> +               dev_err(dev, "can't set alarm to requested time\n");
> +               return -EINVAL;
> +       }

> +
> +       buff[0] = bin2bcd(alrm->time.tm_sec);
> +       buff[1] = bin2bcd(alrm->time.tm_min);
> +       buff[2] = bin2bcd(alrm->time.tm_hour);
> +       buff[3] = bin2bcd(alrm->time.tm_mday);
> +       buff[4] = bin2bcd(alrm->time.tm_mon + 1);
> +       buff[5] = bin2bcd(alrm->time.tm_year % RTC_YEAR_OFFSET);
> +       ret = tps80031_writes(dev->parent, TPS80031_SLAVE_ID1,
> +                       TPS80031_ALARM_SECONDS_REG,
> +                       TPS80031_RTC_ALARM_NUM_REGS, buff);
> +       if (ret < 0) {
> +               dev_err(dev, "Writing RTC_ALARM failed, err %d\n", ret);
> +               return ret;
> +       }
> +       return tps80031_rtc_alarm_irq_enable(dev, alrm->enabled);

[ snip ]

> +static int __devinit tps80031_rtc_probe(struct platform_device *pdev)
> +{
> +       struct tps80031_rtc *rtc;
> +       struct rtc_time tm;
> +       int ret;
> +
> +       rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
> +       if (!rtc)
> +               return -ENOMEM;
> +
> +       rtc->irq = platform_get_irq(pdev, 0);
> +       platform_set_drvdata(pdev, rtc);
> +
> +       /* Start RTC */
> +       ret = tps80031_set_bits(pdev->dev.parent, TPS80031_SLAVE_ID1,
> +                       TPS80031_RTC_CTRL_REG, STOP_RTC);
> +       if (ret < 0) {
> +               dev_err(&pdev->dev, "failed to start RTC. err = %d\n", ret);
> +               return ret;
> +       }
> +
> +       /* If RTC have POR values, set time 01:01:2000 */
> +       tps80031_rtc_read_time(&pdev->dev, &tm);
> +       if ((tm.tm_year == RTC_YEAR_OFFSET + TPS80031_RTC_POR_YEAR) &&
> +               (tm.tm_mon == (TPS80031_RTC_POR_MONTH - 1)) &&
> +               (tm.tm_mday == TPS80031_RTC_POR_DAY)) {
> +               tm.tm_year = 2000;
> +               tm.tm_mday = 1;
> +               tm.tm_mon = 1;
> +               ret = tps80031_rtc_set_time(&pdev->dev, &tm);
> +               if (ret < 0) {
> +                       dev_err(&pdev->dev,
> +                               "RTC set time failed, err = %d\n", ret);
> +                       return ret;
> +               }
> +       }
> +
> +       /* Clear alarm intretupt status if it is there */
> +       ret = clear_alarm_int_status(&pdev->dev, rtc);
> +       if (ret < 0) {
> +               dev_err(&pdev->dev, "Clear alarm int failed, err = %d\n", ret);
> +               return ret;
> +       }
> +
> +       rtc->rtc = rtc_device_register(pdev->name, &pdev->dev,
> +                              &tps80031_rtc_ops, THIS_MODULE);
> +       if (IS_ERR(rtc->rtc)) {
> +               ret = PTR_ERR(rtc->rtc);
> +               return ret;

                  you can do return PTR_ERR(rtc->rtc); instead saving
that and returning, but this is just trivial.

> +       }
> +
> +       ret = request_threaded_irq(rtc->irq, NULL, tps80031_rtc_irq,
> +                       IRQF_ONESHOT | IRQF_EARLY_RESUME,
> +                       dev_name(&pdev->dev), rtc);
> +       if (ret < 0) {
> +               dev_err(&pdev->dev, "request IRQ:%d failed, err = %d\n",
> +                        rtc->irq, ret);
> +               rtc_device_unregister(rtc->rtc);
> +               return ret;
> +       }
> +       device_set_wakeup_capable(&pdev->dev, 1);
> +       return 0;
> +}
> +
> +static int __devexit tps80031_rtc_remove(struct platform_device *pdev)
> +{
> +       struct tps80031_rtc *rtc = platform_get_drvdata(pdev);
> +
> +       free_irq(rtc->irq, rtc);
> +       rtc_device_unregister(rtc->rtc);
> +       return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int tps80031_rtc_suspend(struct device *dev)
> +{
> +       struct tps80031_rtc *rtc = dev_get_drvdata(dev);
> +
> +       if (device_may_wakeup(dev))
> +               enable_irq_wake(rtc->irq);
> +       return 0;
> +}
> +
> +static int tps80031_rtc_resume(struct device *dev)
> +{
> +       struct tps80031_rtc *rtc = dev_get_drvdata(dev);
> +
> +       if (device_may_wakeup(dev))
> +               disable_irq_wake(rtc->irq);
> +       return 0;
> +};
> +#endif
> +
> +static const struct dev_pm_ops tps80031_pm_ops = {
> +       SET_SYSTEM_SLEEP_PM_OPS(tps80031_rtc_suspend, tps80031_rtc_resume)

say we dont have enabled CONFIG_PM_SLEEP, will we get an compiler error ?

> +};
> +
> +static struct platform_driver tps80031_rtc_driver = {
> +       .driver = {
> +               .name   = "tps80031-rtc",
> +               .owner  = THIS_MODULE,
> +               .pm     = &tps80031_pm_ops,
> +       },
> +       .probe  = tps80031_rtc_probe,
> +       .remove = __devexit_p(tps80031_rtc_remove),
> +};
> +
> +module_platform_driver(tps80031_rtc_driver);
> +
> +MODULE_ALIAS("platform:tps80031-rtc");
> +MODULE_DESCRIPTION("TI TPS80031/TPS80032 RTC driver");
> +MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
> +MODULE_LICENSE("GPL v2");
> --
> 1.7.1.1
>
> --
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> Please read the FAQ at  http://www.tux.org/lkml/
Laxman Dewangan - Dec. 24, 2012, 10:28 a.m.
Thanks Devendra for quick review.

Following are my response specific to query.

I will post the next patch for taking care of comments.



On Monday 24 December 2012 03:32 PM, devendra.aaru wrote:
> Hello,
>
> On Mon, Dec 24, 2012 at 3:04 PM, Laxman Dewangan<ldewangan@nvidia.com>  wrote:
>> Add an RTC driver for TPS80031/TPS80032 chips by TI.
>> This driver supports:
>> - Setting and getting time and date.
>> - Setting and reading alarm time.
>> - Alarm and interrupt functionlity.
>>
>
>> +
>> +       if (alrm->enabled&&  (seconds<  epoch_start)) {
> its better to have this check in the core itself rather duplicating
> everywhere, but i think the core already have this check, will you
> please check ?

Yes, it is there in __rtc_set_alarm() of interface.c file. I will remove 
this in next patch.


>> +
>> +static const struct dev_pm_ops tps80031_pm_ops = {
>> +       SET_SYSTEM_SLEEP_PM_OPS(tps80031_rtc_suspend, tps80031_rtc_resume)
> say we dont have enabled CONFIG_PM_SLEEP, will we get an compiler error ?

No compilation error. This is already taken care in on pm.h.
> Please read the FAQ at  http://www.tux.org/lkml/
Devendra Naga - Dec. 24, 2012, 10:31 a.m.
Hello,

On Mon, Dec 24, 2012 at 3:58 PM, Laxman Dewangan <ldewangan@nvidia.com> wrote:
> Thanks Devendra for quick review.
>
> Following are my response specific to query.
>
> I will post the next patch for taking care of comments.
>
>

thanks :)

>
>
> On Monday 24 December 2012 03:32 PM, devendra.aaru wrote:
>>
>> Hello,
>>
>> On Mon, Dec 24, 2012 at 3:04 PM, Laxman Dewangan<ldewangan@nvidia.com>
>> wrote:
>>>
>>> Add an RTC driver for TPS80031/TPS80032 chips by TI.
>>> This driver supports:
>>> - Setting and getting time and date.
>>> - Setting and reading alarm time.
>>> - Alarm and interrupt functionlity.
>>>
>>
>>> +
>>> +       if (alrm->enabled&&  (seconds<  epoch_start)) {
>>
>> its better to have this check in the core itself rather duplicating
>> everywhere, but i think the core already have this check, will you
>> please check ?
>
>
> Yes, it is there in __rtc_set_alarm() of interface.c file. I will remove
> this in next patch.
>

ok.

>
>
>>> +
>>> +static const struct dev_pm_ops tps80031_pm_ops = {
>>> +       SET_SYSTEM_SLEEP_PM_OPS(tps80031_rtc_suspend,
>>> tps80031_rtc_resume)
>>
>> say we dont have enabled CONFIG_PM_SLEEP, will we get an compiler error ?
>
>
> No compilation error. This is already taken care in on pm.h.
>

ok good to know, sorry for disturbing you with this comment.

>> Please read the FAQ at  http://www.tux.org/lkml/
>
>

Patch

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 923a9da..adf8a97 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -370,6 +370,14 @@  config RTC_DRV_TPS65910
 	  This driver can also be built as a module. If so, the module
 	  will be called rtc-tps65910.
 
+config RTC_DRV_TPS80031
+	tristate "TI TPS80031/TPS80032 RTC driver"
+	depends on MFD_TPS80031
+	help
+	  TI Power Managment IC TPS80031 supports RTC functionality
+	  along with alarm. This driver supports the RTC driver for
+	  the TPS80031 RTC module.
+
 config RTC_DRV_RC5T583
 	tristate "RICOH 5T583 RTC driver"
 	depends on MFD_RC5T583
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 4418ef3..9881e35 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -113,6 +113,7 @@  obj-$(CONFIG_RTC_DRV_TILE)	+= rtc-tile.o
 obj-$(CONFIG_RTC_DRV_TWL4030)	+= rtc-twl.o
 obj-$(CONFIG_RTC_DRV_TPS6586X)	+= rtc-tps6586x.o
 obj-$(CONFIG_RTC_DRV_TPS65910)	+= rtc-tps65910.o
+obj-$(CONFIG_RTC_DRV_TPS80031)	+= rtc-tps80031.o
 obj-$(CONFIG_RTC_DRV_TX4939)	+= rtc-tx4939.o
 obj-$(CONFIG_RTC_DRV_V3020)	+= rtc-v3020.o
 obj-$(CONFIG_RTC_DRV_VR41XX)	+= rtc-vr41xx.o
diff --git a/drivers/rtc/rtc-tps80031.c b/drivers/rtc/rtc-tps80031.c
new file mode 100644
index 0000000..d412e8c
--- /dev/null
+++ b/drivers/rtc/rtc-tps80031.c
@@ -0,0 +1,363 @@ 
+/*
+ * rtc-tps80031.c -- TI TPS80031/TPS80032 RTC driver
+ *
+ * RTC driver for TI TPS80031/TPS80032 Fully Integrated
+ * Power Management with Power Path and Battery Charger
+ *
+ * Copyright (c) 2012, NVIDIA Corporation.
+ *
+ * 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
+ * published by the Free Software Foundation version 2.
+ *
+ * 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ * 02111-1307, USA
+ */
+
+#include <linux/bcd.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mfd/tps80031.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <linux/slab.h>
+
+#define ENABLE_ALARM_INT			0x08
+#define ALARM_INT_STATUS			0x40
+
+/**
+ * Setting bit to 1 in STOP_RTC will run the RTC and
+ * setting this bit to 0 will freeze RTC.
+ */
+#define STOP_RTC				0x1
+
+/* Power on reset Values of RTC registers */
+#define TPS80031_RTC_POR_YEAR			0
+#define TPS80031_RTC_POR_MONTH			1
+#define TPS80031_RTC_POR_DAY			1
+
+/* Numbers of registers for time and alarms */
+#define TPS80031_RTC_TIME_NUM_REGS		7
+#define TPS80031_RTC_ALARM_NUM_REGS		6
+
+/**
+ * PMU RTC have only 2 nibbles to store year information, so using an
+ * offset of 100 to set the base year as 2000 for our driver.
+ */
+#define RTC_YEAR_OFFSET 100
+
+struct tps80031_rtc {
+	struct rtc_device	*rtc;
+	int			irq;
+};
+
+static int tps80031_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	u8 buff[TPS80031_RTC_TIME_NUM_REGS];
+	int ret;
+
+	ret = tps80031_reads(dev->parent, TPS80031_SLAVE_ID1,
+			TPS80031_SECONDS_REG, TPS80031_RTC_TIME_NUM_REGS, buff);
+	if (ret < 0) {
+		dev_err(dev, "reading RTC_SECONDS_REG failed, err = %d\n", ret);
+		return ret;
+	}
+
+	tm->tm_sec = bcd2bin(buff[0]);
+	tm->tm_min = bcd2bin(buff[1]);
+	tm->tm_hour = bcd2bin(buff[2]);
+	tm->tm_mday = bcd2bin(buff[3]);
+	tm->tm_mon = bcd2bin(buff[4]) - 1;
+	tm->tm_year = bcd2bin(buff[5]) + RTC_YEAR_OFFSET;
+	tm->tm_wday = bcd2bin(buff[6]);
+	return 0;
+}
+
+static int tps80031_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	u8 buff[7];
+	int ret;
+
+	buff[0] = bin2bcd(tm->tm_sec);
+	buff[1] = bin2bcd(tm->tm_min);
+	buff[2] = bin2bcd(tm->tm_hour);
+	buff[3] = bin2bcd(tm->tm_mday);
+	buff[4] = bin2bcd(tm->tm_mon + 1);
+	buff[5] = bin2bcd(tm->tm_year % RTC_YEAR_OFFSET);
+	buff[6] = bin2bcd(tm->tm_wday);
+
+	/* Stop RTC while updating the RTC time registers */
+	ret = tps80031_clr_bits(dev->parent, TPS80031_SLAVE_ID1,
+				TPS80031_RTC_CTRL_REG, STOP_RTC);
+	if (ret < 0) {
+		dev_err(dev->parent, "Stop RTC failed, err = %d\n", ret);
+		return ret;
+	}
+
+	ret = tps80031_writes(dev->parent, TPS80031_SLAVE_ID1,
+			TPS80031_SECONDS_REG,
+			TPS80031_RTC_TIME_NUM_REGS, buff);
+	if (ret < 0) {
+		dev_err(dev, "writing RTC_SECONDS_REG failed, err %d\n", ret);
+		return ret;
+	}
+
+	ret = tps80031_set_bits(dev->parent, TPS80031_SLAVE_ID1,
+				TPS80031_RTC_CTRL_REG, STOP_RTC);
+	if (ret < 0)
+		dev_err(dev->parent, "Start RTC failed, err = %d\n", ret);
+	return ret;
+}
+
+static int tps80031_rtc_alarm_irq_enable(struct device *dev,
+					 unsigned int enable)
+{
+	int ret;
+
+	if (enable)
+		ret = tps80031_set_bits(dev->parent, TPS80031_SLAVE_ID1,
+				TPS80031_RTC_INTERRUPTS_REG, ENABLE_ALARM_INT);
+	else
+		ret = tps80031_clr_bits(dev->parent, TPS80031_SLAVE_ID1,
+				TPS80031_RTC_INTERRUPTS_REG, ENABLE_ALARM_INT);
+	if (ret < 0) {
+		dev_err(dev, "Update on RTC_INT failed, err = %d\n", ret);
+		return ret;
+	}
+	return 0;
+}
+
+static int tps80031_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct rtc_time tm;
+	unsigned long seconds;
+	u8 buff[TPS80031_RTC_ALARM_NUM_REGS];
+	int ret;
+	unsigned long epoch_start;
+
+	rtc_tm_to_time(&alrm->time, &seconds);
+	ret = tps80031_rtc_read_time(dev, &tm);
+	if (ret < 0) {
+		dev_err(dev, "Error in getting current time, err = %d\n", ret);
+		return ret;
+	}
+	rtc_tm_to_time(&tm, &epoch_start);
+
+	if (alrm->enabled && (seconds < epoch_start)) {
+		dev_err(dev, "can't set alarm to requested time\n");
+		return -EINVAL;
+	}
+
+	buff[0] = bin2bcd(alrm->time.tm_sec);
+	buff[1] = bin2bcd(alrm->time.tm_min);
+	buff[2] = bin2bcd(alrm->time.tm_hour);
+	buff[3] = bin2bcd(alrm->time.tm_mday);
+	buff[4] = bin2bcd(alrm->time.tm_mon + 1);
+	buff[5] = bin2bcd(alrm->time.tm_year % RTC_YEAR_OFFSET);
+	ret = tps80031_writes(dev->parent, TPS80031_SLAVE_ID1,
+			TPS80031_ALARM_SECONDS_REG,
+			TPS80031_RTC_ALARM_NUM_REGS, buff);
+	if (ret < 0) {
+		dev_err(dev, "Writing RTC_ALARM failed, err %d\n", ret);
+		return ret;
+	}
+	return tps80031_rtc_alarm_irq_enable(dev, alrm->enabled);
+}
+
+static int tps80031_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	u8 buff[6];
+	int ret;
+
+	ret = tps80031_reads(dev->parent, TPS80031_SLAVE_ID1,
+			TPS80031_ALARM_SECONDS_REG,
+			TPS80031_RTC_ALARM_NUM_REGS, buff);
+	if (ret < 0) {
+		dev_err(dev->parent,
+			"reading RTC_ALARM failed, err = %d\n", ret);
+		return ret;
+	}
+
+	alrm->time.tm_sec = bcd2bin(buff[0]);
+	alrm->time.tm_min = bcd2bin(buff[1]);
+	alrm->time.tm_hour = bcd2bin(buff[2]);
+	alrm->time.tm_mday = bcd2bin(buff[3]);
+	alrm->time.tm_mon = bcd2bin(buff[4]) - 1;
+	alrm->time.tm_year = bcd2bin(buff[5]) + RTC_YEAR_OFFSET;
+	return 0;
+}
+
+static int clear_alarm_int_status(struct device *dev, struct tps80031_rtc *rtc)
+{
+	int ret;
+	u8 buf;
+
+	/**
+	 * As per datasheet, A dummy read of this  RTC_STATUS_REG register
+	 * is necessary before each I2C read in order to update the status
+	 * register value.
+	 */
+	ret = tps80031_read(dev->parent, TPS80031_SLAVE_ID1,
+				TPS80031_RTC_STATUS_REG, &buf);
+	if (ret < 0) {
+		dev_err(dev, "reading RTC_STATUS failed. err = %d\n", ret);
+		return ret;
+	}
+
+	/* clear Alarm status bits.*/
+	ret = tps80031_set_bits(dev->parent, TPS80031_SLAVE_ID1,
+			TPS80031_RTC_STATUS_REG, ALARM_INT_STATUS);
+	if (ret < 0) {
+		dev_err(dev, "clear Alarm INT failed, err = %d\n", ret);
+		return ret;
+	}
+	return 0;
+}
+
+static irqreturn_t tps80031_rtc_irq(int irq, void *data)
+{
+	struct device *dev = data;
+	struct tps80031_rtc *rtc = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clear_alarm_int_status(dev, rtc);
+	if (ret < 0)
+		return ret;
+
+	rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);
+	return IRQ_HANDLED;
+}
+
+static const struct rtc_class_ops tps80031_rtc_ops = {
+	.read_time = tps80031_rtc_read_time,
+	.set_time = tps80031_rtc_set_time,
+	.set_alarm = tps80031_rtc_set_alarm,
+	.read_alarm = tps80031_rtc_read_alarm,
+	.alarm_irq_enable = tps80031_rtc_alarm_irq_enable,
+};
+
+static int __devinit tps80031_rtc_probe(struct platform_device *pdev)
+{
+	struct tps80031_rtc *rtc;
+	struct rtc_time tm;
+	int ret;
+
+	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
+	if (!rtc)
+		return -ENOMEM;
+
+	rtc->irq = platform_get_irq(pdev, 0);
+	platform_set_drvdata(pdev, rtc);
+
+	/* Start RTC */
+	ret = tps80031_set_bits(pdev->dev.parent, TPS80031_SLAVE_ID1,
+			TPS80031_RTC_CTRL_REG, STOP_RTC);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to start RTC. err = %d\n", ret);
+		return ret;
+	}
+
+	/* If RTC have POR values, set time 01:01:2000 */
+	tps80031_rtc_read_time(&pdev->dev, &tm);
+	if ((tm.tm_year == RTC_YEAR_OFFSET + TPS80031_RTC_POR_YEAR) &&
+		(tm.tm_mon == (TPS80031_RTC_POR_MONTH - 1)) &&
+		(tm.tm_mday == TPS80031_RTC_POR_DAY)) {
+		tm.tm_year = 2000;
+		tm.tm_mday = 1;
+		tm.tm_mon = 1;
+		ret = tps80031_rtc_set_time(&pdev->dev, &tm);
+		if (ret < 0) {
+			dev_err(&pdev->dev,
+				"RTC set time failed, err = %d\n", ret);
+			return ret;
+		}
+	}
+
+	/* Clear alarm intretupt status if it is there */
+	ret = clear_alarm_int_status(&pdev->dev, rtc);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Clear alarm int failed, err = %d\n", ret);
+		return ret;
+	}
+
+	rtc->rtc = rtc_device_register(pdev->name, &pdev->dev,
+			       &tps80031_rtc_ops, THIS_MODULE);
+	if (IS_ERR(rtc->rtc)) {
+		ret = PTR_ERR(rtc->rtc);
+		return ret;
+	}
+
+	ret = request_threaded_irq(rtc->irq, NULL, tps80031_rtc_irq,
+			IRQF_ONESHOT | IRQF_EARLY_RESUME,
+			dev_name(&pdev->dev), rtc);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "request IRQ:%d failed, err = %d\n",
+			 rtc->irq, ret);
+		rtc_device_unregister(rtc->rtc);
+		return ret;
+	}
+	device_set_wakeup_capable(&pdev->dev, 1);
+	return 0;
+}
+
+static int __devexit tps80031_rtc_remove(struct platform_device *pdev)
+{
+	struct tps80031_rtc *rtc = platform_get_drvdata(pdev);
+
+	free_irq(rtc->irq, rtc);
+	rtc_device_unregister(rtc->rtc);
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int tps80031_rtc_suspend(struct device *dev)
+{
+	struct tps80031_rtc *rtc = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev))
+		enable_irq_wake(rtc->irq);
+	return 0;
+}
+
+static int tps80031_rtc_resume(struct device *dev)
+{
+	struct tps80031_rtc *rtc = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev))
+		disable_irq_wake(rtc->irq);
+	return 0;
+};
+#endif
+
+static const struct dev_pm_ops tps80031_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(tps80031_rtc_suspend, tps80031_rtc_resume)
+};
+
+static struct platform_driver tps80031_rtc_driver = {
+	.driver	= {
+		.name	= "tps80031-rtc",
+		.owner	= THIS_MODULE,
+		.pm	= &tps80031_pm_ops,
+	},
+	.probe	= tps80031_rtc_probe,
+	.remove	= __devexit_p(tps80031_rtc_remove),
+};
+
+module_platform_driver(tps80031_rtc_driver);
+
+MODULE_ALIAS("platform:tps80031-rtc");
+MODULE_DESCRIPTION("TI TPS80031/TPS80032 RTC driver");
+MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
+MODULE_LICENSE("GPL v2");