ENGR00141217-6 srtc: add rtc driver for 2.6.38

Add srtc support

Signed-off-by: Frank Li <Frank.Li@freescale.com>

3 files changed, 763 insertions, 0 deletions

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index ce2aabf5c550..f2e0eaf6134e 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -634,6 +634,13 @@ config RTC_MXC
 	   This driver can also be built as a module, if so, the module
 	   will be called "rtc-mxc".
 
+config RTC_DRV_MXC_V2
+	tristate "Freescale MXC Secure Real Time Clock"
+	depends on ARCH_MXC
+	depends on RTC_CLASS
+	help
+	   Support for Freescale SRTC MXC
+
 config RTC_DRV_BQ4802
 	tristate "TI BQ4802"
 	help
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 0ffefe877bfa..7e8626d1444e 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -108,3 +108,4 @@ obj-$(CONFIG_RTC_DRV_VT8500)	+= rtc-vt8500.o
 obj-$(CONFIG_RTC_DRV_WM831X)	+= rtc-wm831x.o
 obj-$(CONFIG_RTC_DRV_WM8350)	+= rtc-wm8350.o
 obj-$(CONFIG_RTC_DRV_X1205)	+= rtc-x1205.o
+obj-$(CONFIG_RTC_DRV_MXC_V2)    += rtc-mxc_v2.o
diff --git a/drivers/rtc/rtc-mxc_v2.c b/drivers/rtc/rtc-mxc_v2.c
new file mode 100644
index 000000000000..7737420cac9b
--- /dev/null
+++ b/drivers/rtc/rtc-mxc_v2.c
@@ -0,0 +1,755 @@
+/*
+ * Copyright (C) 2004-2011 Freescale Semiconductor, Inc. All Rights Reserved.
+ */
+
+/*
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+/*
+ * Implementation based on rtc-ds1553.c
+ */
+
+/*!
+ * @defgroup RTC Real Time Clock (RTC) Driver
+ */
+/*!
+ * @file rtc-mxc_v2.c
+ * @brief Real Time Clock interface
+ *
+ * This file contains Real Time Clock interface for Linux.
+ *
+ * @ingroup RTC
+ */
+
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/rtc.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+#include <linux/sched.h>
+#include <linux/mxc_srtc.h>
+
+#define SRTC_LPSCLR_LLPSC_LSH	17	 /* start bit for LSB time value */
+
+#define SRTC_LPPDR_INIT       0x41736166	/* init for glitch detect */
+
+#define SRTC_LPCR_SWR_LP      (1 << 0)	/* lp software reset */
+#define SRTC_LPCR_EN_LP       (1 << 3)	/* lp enable */
+#define SRTC_LPCR_WAE         (1 << 4)	/* lp wakeup alarm enable */
+#define SRTC_LPCR_SAE         (1 << 5)	/* lp security alarm enable */
+#define SRTC_LPCR_SI          (1 << 6)	/* lp security interrupt enable */
+#define SRTC_LPCR_ALP         (1 << 7)	/* lp alarm flag */
+#define SRTC_LPCR_LTC         (1 << 8)	/* lp lock time counter */
+#define SRTC_LPCR_LMC         (1 << 9)	/* lp lock monotonic counter */
+#define SRTC_LPCR_SV          (1 << 10)	/* lp security violation */
+#define SRTC_LPCR_NSA         (1 << 11)	/* lp non secure access */
+#define SRTC_LPCR_NVEIE       (1 << 12)	/* lp non valid state exit int en */
+#define SRTC_LPCR_IEIE        (1 << 13)	/* lp init state exit int enable */
+#define SRTC_LPCR_NVE         (1 << 14)	/* lp non valid state exit bit */
+#define SRTC_LPCR_IE          (1 << 15)	/* lp init state exit bit */
+
+#define SRTC_LPCR_ALL_INT_EN (SRTC_LPCR_WAE | SRTC_LPCR_SAE | \
+			      SRTC_LPCR_SI | SRTC_LPCR_ALP | \
+			      SRTC_LPCR_NVEIE | SRTC_LPCR_IEIE)
+
+#define SRTC_LPSR_TRI         (1 << 0)	/* lp time read invalidate */
+#define SRTC_LPSR_PGD         (1 << 1)	/* lp power supply glitc detected */
+#define SRTC_LPSR_CTD         (1 << 2)	/* lp clock tampering detected */
+#define SRTC_LPSR_ALP         (1 << 3)	/* lp alarm flag */
+#define SRTC_LPSR_MR          (1 << 4)	/* lp monotonic counter rollover */
+#define SRTC_LPSR_TR          (1 << 5)	/* lp time rollover */
+#define SRTC_LPSR_EAD         (1 << 6)	/* lp external alarm detected */
+#define SRTC_LPSR_IT0         (1 << 7)	/* lp IIM throttle */
+#define SRTC_LPSR_IT1         (1 << 8)
+#define SRTC_LPSR_IT2         (1 << 9)
+#define SRTC_LPSR_SM0         (1 << 10)	/* lp security mode */
+#define SRTC_LPSR_SM1         (1 << 11)
+#define SRTC_LPSR_STATE_LP0   (1 << 12)	/* lp state */
+#define SRTC_LPSR_STATE_LP1   (1 << 13)
+#define SRTC_LPSR_NVES        (1 << 14)	/* lp non-valid state exit status */
+#define SRTC_LPSR_IES         (1 << 15)	/* lp init state exit status */
+
+#define MAX_PIE_NUM     15
+#define MAX_PIE_FREQ    32768
+#define MIN_PIE_FREQ	1
+
+#define SRTC_PI0         (1 << 0)
+#define SRTC_PI1         (1 << 1)
+#define SRTC_PI2         (1 << 2)
+#define SRTC_PI3         (1 << 3)
+#define SRTC_PI4         (1 << 4)
+#define SRTC_PI5         (1 << 5)
+#define SRTC_PI6         (1 << 6)
+#define SRTC_PI7         (1 << 7)
+#define SRTC_PI8         (1 << 8)
+#define SRTC_PI9         (1 << 9)
+#define SRTC_PI10        (1 << 10)
+#define SRTC_PI11        (1 << 11)
+#define SRTC_PI12        (1 << 12)
+#define SRTC_PI13        (1 << 13)
+#define SRTC_PI14        (1 << 14)
+#define SRTC_PI15        (1 << 15)
+
+#define PIT_ALL_ON      (SRTC_PI1 | SRTC_PI2 | SRTC_PI3 | \
+			SRTC_PI4 | SRTC_PI5 | SRTC_PI6 | SRTC_PI7 | \
+			SRTC_PI8 | SRTC_PI9 | SRTC_PI10 | SRTC_PI11 | \
+			SRTC_PI12 | SRTC_PI13 | SRTC_PI14 | SRTC_PI15)
+
+#define SRTC_SWR_HP      (1 << 0)	/* hp software reset */
+#define SRTC_EN_HP       (1 << 3)	/* hp enable */
+#define SRTC_TS          (1 << 4)	/* time syncronize hp with lp */
+
+#define SRTC_IE_AHP      (1 << 16)	/* Alarm HP Interrupt Enable bit */
+#define SRTC_IE_WDHP     (1 << 18)	/* Write Done HP Interrupt Enable bit */
+#define SRTC_IE_WDLP     (1 << 19)	/* Write Done LP Interrupt Enable bit */
+
+#define SRTC_ISR_AHP     (1 << 16)	/* interrupt status: alarm hp */
+#define SRTC_ISR_WDHP    (1 << 18)	/* interrupt status: write done hp */
+#define SRTC_ISR_WDLP    (1 << 19)	/* interrupt status: write done lp */
+#define SRTC_ISR_WPHP    (1 << 20)	/* interrupt status: write pending hp */
+#define SRTC_ISR_WPLP    (1 << 21)	/* interrupt status: write pending lp */
+
+#define SRTC_LPSCMR	0x00	/* LP Secure Counter MSB Reg */
+#define SRTC_LPSCLR	0x04	/* LP Secure Counter LSB Reg */
+#define SRTC_LPSAR	0x08	/* LP Secure Alarm Reg */
+#define SRTC_LPSMCR	0x0C	/* LP Secure Monotonic Counter Reg */
+#define SRTC_LPCR	0x10	/* LP Control Reg */
+#define SRTC_LPSR	0x14	/* LP Status Reg */
+#define SRTC_LPPDR	0x18	/* LP Power Supply Glitch Detector Reg */
+#define SRTC_LPGR	0x1C	/* LP General Purpose Reg */
+#define SRTC_HPCMR	0x20	/* HP Counter MSB Reg */
+#define SRTC_HPCLR	0x24	/* HP Counter LSB Reg */
+#define SRTC_HPAMR	0x28	/* HP Alarm MSB Reg */
+#define SRTC_HPALR	0x2C	/* HP Alarm LSB Reg */
+#define SRTC_HPCR	0x30	/* HP Control Reg */
+#define SRTC_HPISR	0x34	/* HP Interrupt Status Reg */
+#define SRTC_HPIENR	0x38	/* HP Interrupt Enable Reg */
+
+#define SRTC_SECMODE_MASK	0x3	/* the mask of SRTC security mode */
+#define SRTC_SECMODE_LOW	0x0	/* Low Security */
+#define SRTC_SECMODE_MED	0x1	/* Medium Security */
+#define SRTC_SECMODE_HIGH	0x2	/* High Security */
+#define SRTC_SECMODE_RESERVED	0x3	/* Reserved */
+
+struct rtc_drv_data {
+	struct rtc_device *rtc;
+	void __iomem *ioaddr;
+	unsigned long baseaddr;
+	int irq;
+	struct clk *clk;
+	bool irq_enable;
+};
+
+
+/* completion event for implementing RTC_WAIT_FOR_TIME_SET ioctl */
+DECLARE_COMPLETION(srtc_completion);
+/* global to save difference of 47-bit counter value */
+static int64_t time_diff;
+
+/*!
+ * @defgroup RTC Real Time Clock (RTC) Driver
+ */
+/*!
+ * @file rtc-mxc.c
+ * @brief Real Time Clock interface
+ *
+ * This file contains Real Time Clock interface for Linux.
+ *
+ * @ingroup RTC
+ */
+
+static unsigned long rtc_status;
+
+static DEFINE_SPINLOCK(rtc_lock);
+
+/*!
+ * This function does write synchronization for writes to the lp srtc block.
+ * To take care of the asynchronous CKIL clock, all writes from the IP domain
+ * will be synchronized to the CKIL domain.
+ */
+static inline void rtc_write_sync_lp(void __iomem *ioaddr)
+{
+	unsigned int i, count;
+	/* Wait for 3 CKIL cycles */
+	for (i = 0; i < 3; i++) {
+		count = __raw_readl(ioaddr + SRTC_LPSCLR);
+		while
+			((__raw_readl(ioaddr + SRTC_LPSCLR)) == count);
+	}
+}
+
+/*!
+ * This function updates the RTC alarm registers and then clears all the
+ * interrupt status bits.
+ *
+ * @param  alrm         the new alarm value to be updated in the RTC
+ *
+ * @return  0 if successful; non-zero otherwise.
+ */
+static int rtc_update_alarm(struct device *dev, struct rtc_time *alrm)
+{
+	struct rtc_drv_data *pdata = dev_get_drvdata(dev);
+	void __iomem *ioaddr = pdata->ioaddr;
+	struct rtc_time alarm_tm, now_tm;
+	unsigned long now, time;
+	int ret;
+
+	now = __raw_readl(ioaddr + SRTC_LPSCMR);
+	rtc_time_to_tm(now, &now_tm);
+
+	alarm_tm.tm_year = now_tm.tm_year;
+	alarm_tm.tm_mon = now_tm.tm_mon;
+	alarm_tm.tm_mday = now_tm.tm_mday;
+
+	alarm_tm.tm_hour = alrm->tm_hour;
+	alarm_tm.tm_min = alrm->tm_min;
+	alarm_tm.tm_sec = alrm->tm_sec;
+
+	rtc_tm_to_time(&now_tm, &now);
+	rtc_tm_to_time(&alarm_tm, &time);
+
+	if (time < now) {
+		time += 60 * 60 * 24;
+		rtc_time_to_tm(time, &alarm_tm);
+	}
+	ret = rtc_tm_to_time(&alarm_tm, &time);
+
+	__raw_writel(time, ioaddr + SRTC_LPSAR);
+
+	/* clear alarm interrupt status bit */
+	__raw_writel(SRTC_LPSR_ALP, ioaddr + SRTC_LPSR);
+
+	return ret;
+}
+
+/*!
+ * This function is the RTC interrupt service routine.
+ *
+ * @param  irq          RTC IRQ number
+ * @param  dev_id       device ID which is not used
+ *
+ * @return IRQ_HANDLED as defined in the include/linux/interrupt.h file.
+ */
+static irqreturn_t mxc_rtc_interrupt(int irq, void *dev_id)
+{
+	struct platform_device *pdev = dev_id;
+	struct rtc_drv_data *pdata = platform_get_drvdata(pdev);
+	void __iomem *ioaddr = pdata->ioaddr;
+	u32 lp_status, lp_cr;
+	u32 events = 0;
+
+	lp_status = __raw_readl(ioaddr + SRTC_LPSR);
+	lp_cr = __raw_readl(ioaddr + SRTC_LPCR);
+
+	/* update irq data & counter */
+	if (lp_status & SRTC_LPSR_ALP) {
+		if (lp_cr & SRTC_LPCR_ALP)
+			events |= (RTC_AF | RTC_IRQF);
+
+		/* disable further lp alarm interrupts */
+		lp_cr &= ~(SRTC_LPCR_ALP | SRTC_LPCR_WAE);
+	}
+
+	/* Update interrupt enables */
+	__raw_writel(lp_cr, ioaddr + SRTC_LPCR);
+
+	/* If no interrupts are enabled, turn off interrupts in kernel */
+	if (((lp_cr & SRTC_LPCR_ALL_INT_EN) == 0) && (pdata->irq_enable)) {
+		disable_irq_nosync(pdata->irq);
+		pdata->irq_enable = false;
+	}
+
+	/* clear interrupt status */
+	__raw_writel(lp_status, ioaddr + SRTC_LPSR);
+
+	rtc_update_irq(pdata->rtc, 1, events);
+	return IRQ_HANDLED;
+}
+
+/*!
+ * This function is used to open the RTC driver.
+ *
+ * @return  0 if successful; non-zero otherwise.
+ */
+static int mxc_rtc_open(struct device *dev)
+{
+	if (test_and_set_bit(1, &rtc_status))
+		return -EBUSY;
+	return 0;
+}
+
+/*!
+ * clear all interrupts and release the IRQ
+ */
+static void mxc_rtc_release(struct device *dev)
+{
+	rtc_status = 0;
+}
+
+/*!
+ * This function is used to support some ioctl calls directly.
+ * Other ioctl calls are supported indirectly through the
+ * arm/common/rtctime.c file.
+ *
+ * @param  cmd          ioctl command as defined in include/linux/rtc.h
+ * @param  arg          value for the ioctl command
+ *
+ * @return  0 if successful or negative value otherwise.
+ */
+static int mxc_rtc_ioctl(struct device *dev, unsigned int cmd,
+			 unsigned long arg)
+{
+	struct rtc_drv_data *pdata = dev_get_drvdata(dev);
+	void __iomem *ioaddr = pdata->ioaddr;
+	unsigned long lock_flags = 0;
+	u32 lp_cr;
+	u64 time_47bit;
+	int retVal;
+
+	switch (cmd) {
+	case RTC_AIE_OFF:
+		spin_lock_irqsave(&rtc_lock, lock_flags);
+		lp_cr = __raw_readl(ioaddr + SRTC_LPCR);
+		lp_cr &= ~(SRTC_LPCR_ALP | SRTC_LPCR_WAE);
+		if (((lp_cr & SRTC_LPCR_ALL_INT_EN) == 0)
+		    && (pdata->irq_enable)) {
+			disable_irq(pdata->irq);
+			pdata->irq_enable = false;
+		}
+		__raw_writel(lp_cr, ioaddr + SRTC_LPCR);
+		spin_unlock_irqrestore(&rtc_lock, lock_flags);
+		return 0;
+
+	case RTC_AIE_ON:
+		spin_lock_irqsave(&rtc_lock, lock_flags);
+		if (!pdata->irq_enable) {
+			enable_irq(pdata->irq);
+			pdata->irq_enable = true;
+		}
+		lp_cr = __raw_readl(ioaddr + SRTC_LPCR);
+		lp_cr |= SRTC_LPCR_ALP | SRTC_LPCR_WAE;
+		__raw_writel(lp_cr, ioaddr + SRTC_LPCR);
+		spin_unlock_irqrestore(&rtc_lock, lock_flags);
+		return 0;
+
+	case RTC_READ_TIME_47BIT:
+		time_47bit = (((u64) __raw_readl(ioaddr + SRTC_LPSCMR)) << 32 |
+			((u64) __raw_readl(ioaddr + SRTC_LPSCLR)));
+		time_47bit >>= SRTC_LPSCLR_LLPSC_LSH;
+
+		if (arg && copy_to_user((u64 *) arg, &time_47bit, sizeof(u64)))
+			return -EFAULT;
+
+		return 0;
+
+	/* This IOCTL to be used by processes to be notified of time changes */
+	case RTC_WAIT_TIME_SET:
+
+		/* don't block without releasing mutex first */
+		mutex_unlock(&pdata->rtc->ops_lock);
+
+		/* sleep until awakened by SRTC driver when LPSCMR is changed */
+		wait_for_completion(&srtc_completion);
+
+		/* relock mutex because rtc_dev_ioctl will unlock again */
+		retVal = mutex_lock_interruptible(&pdata->rtc->ops_lock);
+
+		/* copy the new time difference = new time - previous time
+		  * to the user param. The difference is a signed value */
+		if (arg && copy_to_user((int64_t *) arg, &time_diff,
+			sizeof(int64_t)))
+			return -EFAULT;
+
+		return retVal;
+
+	}
+
+	return -ENOIOCTLCMD;
+}
+
+/*!
+ * This function reads the current RTC time into tm in Gregorian date.
+ *
+ * @param  tm           contains the RTC time value upon return
+ *
+ * @return  0 if successful; non-zero otherwise.
+ */
+static int mxc_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct rtc_drv_data *pdata = dev_get_drvdata(dev);
+	void __iomem *ioaddr = pdata->ioaddr;
+
+	rtc_time_to_tm(__raw_readl(ioaddr + SRTC_LPSCMR), tm);
+	return 0;
+}
+
+/*!
+ * This function sets the internal RTC time based on tm in Gregorian date.
+ *
+ * @param  tm           the time value to be set in the RTC
+ *
+ * @return  0 if successful; non-zero otherwise.
+ */
+static int mxc_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct rtc_drv_data *pdata = dev_get_drvdata(dev);
+	void __iomem *ioaddr = pdata->ioaddr;
+	unsigned long time;
+	u64 old_time_47bit, new_time_47bit;
+	int ret;
+	ret = rtc_tm_to_time(tm, &time);
+	if (ret != 0)
+		return ret;
+
+	old_time_47bit = (((u64) __raw_readl(ioaddr + SRTC_LPSCMR)) << 32 |
+			((u64) __raw_readl(ioaddr + SRTC_LPSCLR)));
+	old_time_47bit >>= SRTC_LPSCLR_LLPSC_LSH;
+
+	__raw_writel(time, ioaddr + SRTC_LPSCMR);
+	rtc_write_sync_lp(ioaddr);
+
+	new_time_47bit = (((u64) __raw_readl(ioaddr + SRTC_LPSCMR)) << 32 |
+			((u64) __raw_readl(ioaddr + SRTC_LPSCLR)));
+	new_time_47bit >>= SRTC_LPSCLR_LLPSC_LSH;
+
+	/* update the difference between previous time and new time */
+	time_diff = new_time_47bit - old_time_47bit;
+
+	/* signal all waiting threads that time changed */
+	complete_all(&srtc_completion);
+
+	/* allow signalled threads to handle the time change notification */
+	schedule();
+
+	/* reinitialize completion variable */
+	INIT_COMPLETION(srtc_completion);
+
+	return 0;
+}
+
+/*!
+ * This function reads the current alarm value into the passed in \b alrm
+ * argument. It updates the \b alrm's pending field value based on the whether
+ * an alarm interrupt occurs or not.
+ *
+ * @param  alrm         contains the RTC alarm value upon return
+ *
+ * @return  0 if successful; non-zero otherwise.
+ */
+static int mxc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct rtc_drv_data *pdata = dev_get_drvdata(dev);
+	void __iomem *ioaddr = pdata->ioaddr;
+
+	rtc_time_to_tm(__raw_readl(ioaddr + SRTC_LPSAR), &alrm->time);
+	alrm->pending =
+	    ((__raw_readl(ioaddr + SRTC_LPSR) & SRTC_LPSR_ALP) != 0) ? 1 : 0;
+
+	return 0;
+}
+
+/*!
+ * This function sets the RTC alarm based on passed in alrm.
+ *
+ * @param  alrm         the alarm value to be set in the RTC
+ *
+ * @return  0 if successful; non-zero otherwise.
+ */
+static int mxc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct rtc_drv_data *pdata = dev_get_drvdata(dev);
+	void __iomem *ioaddr = pdata->ioaddr;
+	unsigned long lock_flags = 0;
+	u32 lp_cr;
+	int ret;
+
+	if (rtc_valid_tm(&alrm->time)) {
+		if (alrm->time.tm_sec > 59 ||
+		    alrm->time.tm_hour > 23 || alrm->time.tm_min > 59) {
+			return -EINVAL;
+		}
+	}
+
+	spin_lock_irqsave(&rtc_lock, lock_flags);
+	lp_cr = __raw_readl(ioaddr + SRTC_LPCR);
+
+	ret = rtc_update_alarm(dev, &alrm->time);
+	if (ret)
+		goto out;
+
+	if (alrm->enabled)
+		lp_cr |= (SRTC_LPCR_ALP | SRTC_LPCR_WAE);
+	else
+		lp_cr &= ~(SRTC_LPCR_ALP | SRTC_LPCR_WAE);
+
+	if (lp_cr & SRTC_LPCR_ALL_INT_EN) {
+		if (!pdata->irq_enable) {
+			enable_irq(pdata->irq);
+			pdata->irq_enable = true;
+		}
+	} else {
+		if (pdata->irq_enable) {
+			disable_irq(pdata->irq);
+			pdata->irq_enable = false;
+		}
+	}
+
+	__raw_writel(lp_cr, ioaddr + SRTC_LPCR);
+
+out:
+	spin_unlock_irqrestore(&rtc_lock, lock_flags);
+	rtc_write_sync_lp(ioaddr);
+	return ret;
+}
+
+/*!
+ * This function is used to provide the content for the /proc/driver/rtc
+ * file.
+ *
+ * @param  seq  buffer to hold the information that the driver wants to write
+ *
+ * @return  The number of bytes written into the rtc file.
+ */
+static int mxc_rtc_proc(struct device *dev, struct seq_file *seq)
+{
+	struct rtc_drv_data *pdata = dev_get_drvdata(dev);
+	void __iomem *ioaddr = pdata->ioaddr;
+
+	seq_printf(seq, "alarm_IRQ\t: %s\n",
+		   (((__raw_readl(ioaddr + SRTC_LPCR)) & SRTC_LPCR_ALP) !=
+		    0) ? "yes" : "no");
+
+	return 0;
+}
+
+/*!
+ * The RTC driver structure
+ */
+static struct rtc_class_ops mxc_rtc_ops = {
+	.open = mxc_rtc_open,
+	.release = mxc_rtc_release,
+	.ioctl = mxc_rtc_ioctl,
+	.read_time = mxc_rtc_read_time,
+	.set_time = mxc_rtc_set_time,
+	.read_alarm = mxc_rtc_read_alarm,
+	.set_alarm = mxc_rtc_set_alarm,
+	.proc = mxc_rtc_proc,
+};
+
+/*! MXC RTC Power management control */
+static int mxc_rtc_probe(struct platform_device *pdev)
+{
+	struct clk *clk;
+	struct timespec tv;
+	struct resource *res;
+	struct rtc_device *rtc;
+	struct rtc_drv_data *pdata = NULL;
+	void __iomem *ioaddr;
+	int ret = 0;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
+	if (!pdata)
+		return -ENOMEM;
+
+	pdata->clk = clk_get(&pdev->dev, "rtc_clk");
+	clk_enable(pdata->clk);
+	pdata->baseaddr = res->start;
+	pdata->ioaddr = ioremap(pdata->baseaddr, 0x40);
+	ioaddr = pdata->ioaddr;
+
+	/* Configure and enable the RTC */
+	pdata->irq = platform_get_irq(pdev, 0);
+	if (pdata->irq >= 0) {
+		if (request_irq(pdata->irq, mxc_rtc_interrupt, IRQF_SHARED,
+				pdev->name, pdev) < 0) {
+			dev_warn(&pdev->dev, "interrupt not available.\n");
+			pdata->irq = -1;
+		} else {
+			disable_irq(pdata->irq);
+			pdata->irq_enable = false;
+		}
+	}
+
+	clk = clk_get(&pdev->dev, "rtc_clk");
+	if (clk_get_rate(clk) != 32768) {
+		printk(KERN_ALERT "rtc clock is not valid");
+		ret = -EINVAL;
+		clk_put(clk);
+		goto err_out;
+	}
+	clk_put(clk);
+
+	/* initialize glitch detect */
+	__raw_writel(SRTC_LPPDR_INIT, ioaddr + SRTC_LPPDR);
+	udelay(100);
+
+	/* clear lp interrupt status */
+	__raw_writel(0xFFFFFFFF, ioaddr + SRTC_LPSR);
+	udelay(100);
+
+	/* move out of init state */
+	__raw_writel((SRTC_LPCR_IE | SRTC_LPCR_NSA),
+		     ioaddr + SRTC_LPCR);
+
+	udelay(100);
+
+	while ((__raw_readl(ioaddr + SRTC_LPSR) & SRTC_LPSR_IES) == 0)
+		;
+
+	/* move out of non-valid state */
+	__raw_writel((SRTC_LPCR_IE | SRTC_LPCR_NVE | SRTC_LPCR_NSA |
+		      SRTC_LPCR_EN_LP), ioaddr + SRTC_LPCR);
+
+	udelay(100);
+
+	while ((__raw_readl(ioaddr + SRTC_LPSR) & SRTC_LPSR_NVES) == 0)
+		;
+
+	__raw_writel(0xFFFFFFFF, ioaddr + SRTC_LPSR);
+	udelay(100);
+
+	rtc = rtc_device_register(pdev->name, &pdev->dev,
+				  &mxc_rtc_ops, THIS_MODULE);
+	if (IS_ERR(rtc)) {
+		ret = PTR_ERR(rtc);
+		goto err_out;
+	}
+
+	pdata->rtc = rtc;
+	platform_set_drvdata(pdev, pdata);
+
+	tv.tv_nsec = 0;
+	tv.tv_sec = __raw_readl(ioaddr + SRTC_LPSCMR);
+
+	/* By default, devices should wakeup if they can */
+	/* So srtc is set as "should wakeup" as it can */
+	device_init_wakeup(&pdev->dev, 1);
+
+	return ret;
+
+err_out:
+	clk_disable(pdata->clk);
+	iounmap(ioaddr);
+	if (pdata->irq >= 0)
+		free_irq(pdata->irq, pdev);
+	kfree(pdata);
+	return ret;
+}
+
+static int __exit mxc_rtc_remove(struct platform_device *pdev)
+{
+	struct rtc_drv_data *pdata = platform_get_drvdata(pdev);
+	rtc_device_unregister(pdata->rtc);
+	if (pdata->irq >= 0)
+		free_irq(pdata->irq, pdev);
+
+	clk_disable(pdata->clk);
+	clk_put(pdata->clk);
+	kfree(pdata);
+	return 0;
+}
+
+/*!
+ * This function is called to save the system time delta relative to
+ * the MXC RTC when enterring a low power state. This time delta is
+ * then used on resume to adjust the system time to account for time
+ * loss while suspended.
+ *
+ * @param   pdev  not used
+ * @param   state Power state to enter.
+ *
+ * @return  The function always returns 0.
+ */
+static int mxc_rtc_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct rtc_drv_data *pdata = platform_get_drvdata(pdev);
+
+	if (device_may_wakeup(&pdev->dev)) {
+		enable_irq_wake(pdata->irq);
+	} else {
+		if (pdata->irq_enable)
+			disable_irq(pdata->irq);
+	}
+
+	return 0;
+}
+
+/*!
+ * This function is called to correct the system time based on the
+ * current MXC RTC time relative to the time delta saved during
+ * suspend.
+ *
+ * @param   pdev  not used
+ *
+ * @return  The function always returns 0.
+ */
+static int mxc_rtc_resume(struct platform_device *pdev)
+{
+	struct rtc_drv_data *pdata = platform_get_drvdata(pdev);
+
+	if (device_may_wakeup(&pdev->dev)) {
+		disable_irq_wake(pdata->irq);
+	} else {
+		if (pdata->irq_enable)
+			enable_irq(pdata->irq);
+	}
+
+	return 0;
+}
+
+/*!
+ * Contains pointers to the power management callback functions.
+ */
+static struct platform_driver mxc_rtc_driver = {
+	.driver = {
+		   .name = "mxc_rtc",
+		   },
+	.probe = mxc_rtc_probe,
+	.remove = __exit_p(mxc_rtc_remove),
+	.suspend = mxc_rtc_suspend,
+	.resume = mxc_rtc_resume,
+};
+
+/*!
+ * This function creates the /proc/driver/rtc file and registers the device RTC
+ * in the /dev/misc directory. It also reads the RTC value from external source
+ * and setup the internal RTC properly.
+ *
+ * @return  -1 if RTC is failed to initialize; 0 is successful.
+ */
+static int __init mxc_rtc_init(void)
+{
+	return platform_driver_register(&mxc_rtc_driver);
+}
+
+/*!
+ * This function removes the /proc/driver/rtc file and un-registers the
+ * device RTC from the /dev/misc directory.
+ */
+static void __exit mxc_rtc_exit(void)
+{
+	platform_driver_unregister(&mxc_rtc_driver);
+
+}
+
+module_init(mxc_rtc_init);
+module_exit(mxc_rtc_exit);
+
+MODULE_AUTHOR("Freescale Semiconductor, Inc.");
+MODULE_DESCRIPTION("Realtime Clock Driver (RTC)");
+MODULE_LICENSE("GPL");