drivers/rtc/rtc-lpc32xx.c - kernel/msm-4.9 - Gitiles

 /*
  * Copyright (C) 2010 NXP Semiconductors
  *
  * 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.
  *
  *  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.,
  *  675 Mass Ave, Cambridge, MA 02139, USA.
  */

 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
 #include <linux/spinlock.h>
 #include <linux/rtc.h>
 #include <linux/slab.h>
 #include <linux/io.h>
 #include <linux/of.h>

 /*
  * Clock and Power control register offsets
  */
 #define LPC32XX_RTC_UCOUNT		0x00
 #define LPC32XX_RTC_DCOUNT		0x04
 #define LPC32XX_RTC_MATCH0		0x08
 #define LPC32XX_RTC_MATCH1		0x0C
 #define LPC32XX_RTC_CTRL		0x10
 #define LPC32XX_RTC_INTSTAT		0x14
 #define LPC32XX_RTC_KEY			0x18
 #define LPC32XX_RTC_SRAM		0x80

 #define LPC32XX_RTC_CTRL_MATCH0		(1 << 0)
 #define LPC32XX_RTC_CTRL_MATCH1		(1 << 1)
 #define LPC32XX_RTC_CTRL_ONSW_MATCH0	(1 << 2)
 #define LPC32XX_RTC_CTRL_ONSW_MATCH1	(1 << 3)
 #define LPC32XX_RTC_CTRL_SW_RESET	(1 << 4)
 #define LPC32XX_RTC_CTRL_CNTR_DIS	(1 << 6)
 #define LPC32XX_RTC_CTRL_ONSW_FORCE_HI	(1 << 7)

 #define LPC32XX_RTC_INTSTAT_MATCH0	(1 << 0)
 #define LPC32XX_RTC_INTSTAT_MATCH1	(1 << 1)
 #define LPC32XX_RTC_INTSTAT_ONSW	(1 << 2)

 #define LPC32XX_RTC_KEY_ONSW_LOADVAL	0xB5C13F27

 #define RTC_NAME "rtc-lpc32xx"

 #define rtc_readl(dev, reg) \
 	__raw_readl((dev)->rtc_base + (reg))
 #define rtc_writel(dev, reg, val) \
 	__raw_writel((val), (dev)->rtc_base + (reg))

 struct lpc32xx_rtc {
 	void __iomem *rtc_base;
 	int irq;
 	unsigned char alarm_enabled;
 	struct rtc_device *rtc;
 	spinlock_t lock;
 };

 static int lpc32xx_rtc_read_time(struct device *dev, struct rtc_time *time)
 {
 	unsigned long elapsed_sec;
 	struct lpc32xx_rtc *rtc = dev_get_drvdata(dev);

 	elapsed_sec = rtc_readl(rtc, LPC32XX_RTC_UCOUNT);
 	rtc_time_to_tm(elapsed_sec, time);

 	return rtc_valid_tm(time);
 }

 static int lpc32xx_rtc_set_mmss(struct device *dev, unsigned long secs)
 {
 	struct lpc32xx_rtc *rtc = dev_get_drvdata(dev);
 	u32 tmp;

 	spin_lock_irq(&rtc->lock);

 	/* RTC must be disabled during count update */
 	tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL);
 	rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp | LPC32XX_RTC_CTRL_CNTR_DIS);
 	rtc_writel(rtc, LPC32XX_RTC_UCOUNT, secs);
 	rtc_writel(rtc, LPC32XX_RTC_DCOUNT, 0xFFFFFFFF - secs);
 	rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp &= ~LPC32XX_RTC_CTRL_CNTR_DIS);

 	spin_unlock_irq(&rtc->lock);

 	return 0;
 }

 static int lpc32xx_rtc_read_alarm(struct device *dev,
 	struct rtc_wkalrm *wkalrm)
 {
 	struct lpc32xx_rtc *rtc = dev_get_drvdata(dev);

 	rtc_time_to_tm(rtc_readl(rtc, LPC32XX_RTC_MATCH0), &wkalrm->time);
 	wkalrm->enabled = rtc->alarm_enabled;
 	wkalrm->pending = !!(rtc_readl(rtc, LPC32XX_RTC_INTSTAT) &
 		LPC32XX_RTC_INTSTAT_MATCH0);

 	return rtc_valid_tm(&wkalrm->time);
 }

 static int lpc32xx_rtc_set_alarm(struct device *dev,
 	struct rtc_wkalrm *wkalrm)
 {
 	struct lpc32xx_rtc *rtc = dev_get_drvdata(dev);
 	unsigned long alarmsecs;
 	u32 tmp;
 	int ret;

 	ret = rtc_tm_to_time(&wkalrm->time, &alarmsecs);
 	if (ret < 0) {
 		dev_warn(dev, "Failed to convert time: %d\n", ret);
 		return ret;
 	}

 	spin_lock_irq(&rtc->lock);

 	/* Disable alarm during update */
 	tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL);
 	rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp & ~LPC32XX_RTC_CTRL_MATCH0);

 	rtc_writel(rtc, LPC32XX_RTC_MATCH0, alarmsecs);

 	rtc->alarm_enabled = wkalrm->enabled;
 	if (wkalrm->enabled) {
 		rtc_writel(rtc, LPC32XX_RTC_INTSTAT,
 			   LPC32XX_RTC_INTSTAT_MATCH0);
 		rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp |
 			   LPC32XX_RTC_CTRL_MATCH0);
 	}

 	spin_unlock_irq(&rtc->lock);

 	return 0;
 }

 static int lpc32xx_rtc_alarm_irq_enable(struct device *dev,
 	unsigned int enabled)
 {
 	struct lpc32xx_rtc *rtc = dev_get_drvdata(dev);
 	u32 tmp;

 	spin_lock_irq(&rtc->lock);
 	tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL);

 	if (enabled) {
 		rtc->alarm_enabled = 1;
 		tmp |= LPC32XX_RTC_CTRL_MATCH0;
 	} else {
 		rtc->alarm_enabled = 0;
 		tmp &= ~LPC32XX_RTC_CTRL_MATCH0;
 	}

 	rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp);
 	spin_unlock_irq(&rtc->lock);

 	return 0;
 }

 static irqreturn_t lpc32xx_rtc_alarm_interrupt(int irq, void *dev)
 {
 	struct lpc32xx_rtc *rtc = dev;

 	spin_lock(&rtc->lock);

 	/* Disable alarm interrupt */
 	rtc_writel(rtc, LPC32XX_RTC_CTRL,
 		rtc_readl(rtc, LPC32XX_RTC_CTRL) &
 			  ~LPC32XX_RTC_CTRL_MATCH0);
 	rtc->alarm_enabled = 0;

 	/*
 	 * Write a large value to the match value so the RTC won't
 	 * keep firing the match status
 	 */
 	rtc_writel(rtc, LPC32XX_RTC_MATCH0, 0xFFFFFFFF);
 	rtc_writel(rtc, LPC32XX_RTC_INTSTAT, LPC32XX_RTC_INTSTAT_MATCH0);

 	spin_unlock(&rtc->lock);

 	rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);

 	return IRQ_HANDLED;
 }

 static const struct rtc_class_ops lpc32xx_rtc_ops = {
 	.read_time		= lpc32xx_rtc_read_time,
 	.set_mmss		= lpc32xx_rtc_set_mmss,
 	.read_alarm		= lpc32xx_rtc_read_alarm,
 	.set_alarm		= lpc32xx_rtc_set_alarm,
 	.alarm_irq_enable	= lpc32xx_rtc_alarm_irq_enable,
 };

 static int lpc32xx_rtc_probe(struct platform_device *pdev)
 {
 	struct resource *res;
 	struct lpc32xx_rtc *rtc;
 	resource_size_t size;
 	int rtcirq;
 	u32 tmp;

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res) {
 		dev_err(&pdev->dev, "Can't get memory resource\n");
 		return -ENOENT;
 	}

 	rtcirq = platform_get_irq(pdev, 0);
 	if (rtcirq < 0 || rtcirq >= NR_IRQS) {
 		dev_warn(&pdev->dev, "Can't get interrupt resource\n");
 		rtcirq = -1;
 	}

 	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
 	if (unlikely(!rtc)) {
 		dev_err(&pdev->dev, "Can't allocate memory\n");
 		return -ENOMEM;
 	}
 	rtc->irq = rtcirq;

 	size = resource_size(res);

 	if (!devm_request_mem_region(&pdev->dev, res->start, size,
 				     pdev->name)) {
 		dev_err(&pdev->dev, "RTC registers are not free\n");
 		return -EBUSY;
 	}

 	rtc->rtc_base = devm_ioremap(&pdev->dev, res->start, size);
 	if (!rtc->rtc_base) {
 		dev_err(&pdev->dev, "Can't map memory\n");
 		return -ENOMEM;
 	}

 	spin_lock_init(&rtc->lock);

 	/*
 	 * The RTC is on a separate power domain and can keep it's state
 	 * across a chip power cycle. If the RTC has never been previously
 	 * setup, then set it up now for the first time.
 	 */
 	tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL);
 	if (rtc_readl(rtc, LPC32XX_RTC_KEY) != LPC32XX_RTC_KEY_ONSW_LOADVAL) {
 		tmp &= ~(LPC32XX_RTC_CTRL_SW_RESET |
 			LPC32XX_RTC_CTRL_CNTR_DIS |
 			LPC32XX_RTC_CTRL_MATCH0 |
 			LPC32XX_RTC_CTRL_MATCH1 |
 			LPC32XX_RTC_CTRL_ONSW_MATCH0 |
 			LPC32XX_RTC_CTRL_ONSW_MATCH1 |
 			LPC32XX_RTC_CTRL_ONSW_FORCE_HI);
 		rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp);

 		/* Clear latched interrupt states */
 		rtc_writel(rtc, LPC32XX_RTC_MATCH0, 0xFFFFFFFF);
 		rtc_writel(rtc, LPC32XX_RTC_INTSTAT,
 			   LPC32XX_RTC_INTSTAT_MATCH0 |
 			   LPC32XX_RTC_INTSTAT_MATCH1 |
 			   LPC32XX_RTC_INTSTAT_ONSW);

 		/* Write key value to RTC so it won't reload on reset */
 		rtc_writel(rtc, LPC32XX_RTC_KEY,
 			   LPC32XX_RTC_KEY_ONSW_LOADVAL);
 	} else {
 		rtc_writel(rtc, LPC32XX_RTC_CTRL,
 			   tmp & ~LPC32XX_RTC_CTRL_MATCH0);
 	}

 	platform_set_drvdata(pdev, rtc);

 	rtc->rtc = rtc_device_register(RTC_NAME, &pdev->dev, &lpc32xx_rtc_ops,
 		THIS_MODULE);
 	if (IS_ERR(rtc->rtc)) {
 		dev_err(&pdev->dev, "Can't get RTC\n");
 		platform_set_drvdata(pdev, NULL);
 		return PTR_ERR(rtc->rtc);
 	}

 	/*
 	 * IRQ is enabled after device registration in case alarm IRQ
 	 * is pending upon suspend exit.
 	 */
 	if (rtc->irq >= 0) {
 		if (devm_request_irq(&pdev->dev, rtc->irq,
 				     lpc32xx_rtc_alarm_interrupt,
 				     0, pdev->name, rtc) < 0) {
 			dev_warn(&pdev->dev, "Can't request interrupt.\n");
 			rtc->irq = -1;
 		} else {
 			device_init_wakeup(&pdev->dev, 1);
 		}
 	}

 	return 0;
 }

 static int lpc32xx_rtc_remove(struct platform_device *pdev)
 {
 	struct lpc32xx_rtc *rtc = platform_get_drvdata(pdev);

 	if (rtc->irq >= 0)
 		device_init_wakeup(&pdev->dev, 0);

 	platform_set_drvdata(pdev, NULL);
 	rtc_device_unregister(rtc->rtc);

 	return 0;
 }

 #ifdef CONFIG_PM
 static int lpc32xx_rtc_suspend(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct lpc32xx_rtc *rtc = platform_get_drvdata(pdev);

 	if (rtc->irq >= 0) {
 		if (device_may_wakeup(&pdev->dev))
 			enable_irq_wake(rtc->irq);
 		else
 			disable_irq_wake(rtc->irq);
 	}

 	return 0;
 }

 static int lpc32xx_rtc_resume(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct lpc32xx_rtc *rtc = platform_get_drvdata(pdev);

 	if (rtc->irq >= 0 && device_may_wakeup(&pdev->dev))
 		disable_irq_wake(rtc->irq);

 	return 0;
 }

 /* Unconditionally disable the alarm */
 static int lpc32xx_rtc_freeze(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct lpc32xx_rtc *rtc = platform_get_drvdata(pdev);

 	spin_lock_irq(&rtc->lock);

 	rtc_writel(rtc, LPC32XX_RTC_CTRL,
 		rtc_readl(rtc, LPC32XX_RTC_CTRL) &
 			  ~LPC32XX_RTC_CTRL_MATCH0);

 	spin_unlock_irq(&rtc->lock);

 	return 0;
 }

 static int lpc32xx_rtc_thaw(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct lpc32xx_rtc *rtc = platform_get_drvdata(pdev);

 	if (rtc->alarm_enabled) {
 		spin_lock_irq(&rtc->lock);

 		rtc_writel(rtc, LPC32XX_RTC_CTRL,
 			   rtc_readl(rtc, LPC32XX_RTC_CTRL) |
 			   LPC32XX_RTC_CTRL_MATCH0);

 		spin_unlock_irq(&rtc->lock);
 	}

 	return 0;
 }

 static const struct dev_pm_ops lpc32xx_rtc_pm_ops = {
 	.suspend = lpc32xx_rtc_suspend,
 	.resume = lpc32xx_rtc_resume,
 	.freeze = lpc32xx_rtc_freeze,
 	.thaw = lpc32xx_rtc_thaw,
 	.restore = lpc32xx_rtc_resume
 };

 #define LPC32XX_RTC_PM_OPS (&lpc32xx_rtc_pm_ops)
 #else
 #define LPC32XX_RTC_PM_OPS NULL
 #endif

 #ifdef CONFIG_OF
 static const struct of_device_id lpc32xx_rtc_match[] = {
 	{ .compatible = "nxp,lpc3220-rtc" },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, lpc32xx_rtc_match);
 #endif

 static struct platform_driver lpc32xx_rtc_driver = {
 	.probe		= lpc32xx_rtc_probe,
 	.remove		= lpc32xx_rtc_remove,
 	.driver = {
 		.name	= RTC_NAME,
 		.owner	= THIS_MODULE,
 		.pm	= LPC32XX_RTC_PM_OPS,
 		.of_match_table = of_match_ptr(lpc32xx_rtc_match),
 	},
 };

 module_platform_driver(lpc32xx_rtc_driver);

 MODULE_AUTHOR("Kevin Wells <wellsk40@gmail.com");
 MODULE_DESCRIPTION("RTC driver for the LPC32xx SoC");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:rtc-lpc32xx");
	/*
	* Copyright (C) 2010 NXP Semiconductors
	*
	* 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.
	*
	* 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.,
	* 675 Mass Ave, Cambridge, MA 02139, USA.
	*/

	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/platform_device.h>
	#include <linux/spinlock.h>
	#include <linux/rtc.h>
	#include <linux/slab.h>
	#include <linux/io.h>
	#include <linux/of.h>

	/*
	* Clock and Power control register offsets
	*/
	#define LPC32XX_RTC_UCOUNT 0x00
	#define LPC32XX_RTC_DCOUNT 0x04
	#define LPC32XX_RTC_MATCH0 0x08
	#define LPC32XX_RTC_MATCH1 0x0C
	#define LPC32XX_RTC_CTRL 0x10
	#define LPC32XX_RTC_INTSTAT 0x14
	#define LPC32XX_RTC_KEY 0x18
	#define LPC32XX_RTC_SRAM 0x80

	#define LPC32XX_RTC_CTRL_MATCH0 (1 << 0)
	#define LPC32XX_RTC_CTRL_MATCH1 (1 << 1)
	#define LPC32XX_RTC_CTRL_ONSW_MATCH0 (1 << 2)
	#define LPC32XX_RTC_CTRL_ONSW_MATCH1 (1 << 3)
	#define LPC32XX_RTC_CTRL_SW_RESET (1 << 4)
	#define LPC32XX_RTC_CTRL_CNTR_DIS (1 << 6)
	#define LPC32XX_RTC_CTRL_ONSW_FORCE_HI (1 << 7)

	#define LPC32XX_RTC_INTSTAT_MATCH0 (1 << 0)
	#define LPC32XX_RTC_INTSTAT_MATCH1 (1 << 1)
	#define LPC32XX_RTC_INTSTAT_ONSW (1 << 2)

	#define LPC32XX_RTC_KEY_ONSW_LOADVAL 0xB5C13F27

	#define RTC_NAME "rtc-lpc32xx"

	#define rtc_readl(dev, reg) \
	__raw_readl((dev)->rtc_base + (reg))
	#define rtc_writel(dev, reg, val) \
	__raw_writel((val), (dev)->rtc_base + (reg))

	struct lpc32xx_rtc {
	void __iomem *rtc_base;
	int irq;
	unsigned char alarm_enabled;
	struct rtc_device *rtc;
	spinlock_t lock;
	};

	static int lpc32xx_rtc_read_time(struct device dev, struct rtc_time time)
	{
	unsigned long elapsed_sec;
	struct lpc32xx_rtc *rtc = dev_get_drvdata(dev);

	elapsed_sec = rtc_readl(rtc, LPC32XX_RTC_UCOUNT);
	rtc_time_to_tm(elapsed_sec, time);

	return rtc_valid_tm(time);
	}

	static int lpc32xx_rtc_set_mmss(struct device *dev, unsigned long secs)
	{
	struct lpc32xx_rtc *rtc = dev_get_drvdata(dev);
	u32 tmp;

	spin_lock_irq(&rtc->lock);

	/* RTC must be disabled during count update */
	tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL);
	rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp \| LPC32XX_RTC_CTRL_CNTR_DIS);
	rtc_writel(rtc, LPC32XX_RTC_UCOUNT, secs);
	rtc_writel(rtc, LPC32XX_RTC_DCOUNT, 0xFFFFFFFF - secs);
	rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp &= ~LPC32XX_RTC_CTRL_CNTR_DIS);

	spin_unlock_irq(&rtc->lock);

	return 0;
	}

	static int lpc32xx_rtc_read_alarm(struct device *dev,
	struct rtc_wkalrm *wkalrm)
	{
	struct lpc32xx_rtc *rtc = dev_get_drvdata(dev);

	rtc_time_to_tm(rtc_readl(rtc, LPC32XX_RTC_MATCH0), &wkalrm->time);
	wkalrm->enabled = rtc->alarm_enabled;
	wkalrm->pending = !!(rtc_readl(rtc, LPC32XX_RTC_INTSTAT) &
	LPC32XX_RTC_INTSTAT_MATCH0);

	return rtc_valid_tm(&wkalrm->time);
	}

	static int lpc32xx_rtc_set_alarm(struct device *dev,
	struct rtc_wkalrm *wkalrm)
	{
	struct lpc32xx_rtc *rtc = dev_get_drvdata(dev);
	unsigned long alarmsecs;
	u32 tmp;
	int ret;

	ret = rtc_tm_to_time(&wkalrm->time, &alarmsecs);
	if (ret < 0) {
	dev_warn(dev, "Failed to convert time: %d\n", ret);
	return ret;
	}

	spin_lock_irq(&rtc->lock);

	/* Disable alarm during update */
	tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL);
	rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp & ~LPC32XX_RTC_CTRL_MATCH0);

	rtc_writel(rtc, LPC32XX_RTC_MATCH0, alarmsecs);

	rtc->alarm_enabled = wkalrm->enabled;
	if (wkalrm->enabled) {
	rtc_writel(rtc, LPC32XX_RTC_INTSTAT,
	LPC32XX_RTC_INTSTAT_MATCH0);
	rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp \|
	LPC32XX_RTC_CTRL_MATCH0);
	}

	spin_unlock_irq(&rtc->lock);

	return 0;
	}

	static int lpc32xx_rtc_alarm_irq_enable(struct device *dev,
	unsigned int enabled)
	{
	struct lpc32xx_rtc *rtc = dev_get_drvdata(dev);
	u32 tmp;

	spin_lock_irq(&rtc->lock);
	tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL);

	if (enabled) {
	rtc->alarm_enabled = 1;
	tmp \|= LPC32XX_RTC_CTRL_MATCH0;
	} else {
	rtc->alarm_enabled = 0;
	tmp &= ~LPC32XX_RTC_CTRL_MATCH0;
	}

	rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp);
	spin_unlock_irq(&rtc->lock);

	return 0;
	}

	static irqreturn_t lpc32xx_rtc_alarm_interrupt(int irq, void *dev)
	{
	struct lpc32xx_rtc *rtc = dev;

	spin_lock(&rtc->lock);

	/* Disable alarm interrupt */
	rtc_writel(rtc, LPC32XX_RTC_CTRL,
	rtc_readl(rtc, LPC32XX_RTC_CTRL) &
	~LPC32XX_RTC_CTRL_MATCH0);
	rtc->alarm_enabled = 0;

	/*
	* Write a large value to the match value so the RTC won't
	* keep firing the match status
	*/
	rtc_writel(rtc, LPC32XX_RTC_MATCH0, 0xFFFFFFFF);
	rtc_writel(rtc, LPC32XX_RTC_INTSTAT, LPC32XX_RTC_INTSTAT_MATCH0);

	spin_unlock(&rtc->lock);

	rtc_update_irq(rtc->rtc, 1, RTC_IRQF \| RTC_AF);

	return IRQ_HANDLED;
	}

	static const struct rtc_class_ops lpc32xx_rtc_ops = {
	.read_time = lpc32xx_rtc_read_time,
	.set_mmss = lpc32xx_rtc_set_mmss,
	.read_alarm = lpc32xx_rtc_read_alarm,
	.set_alarm = lpc32xx_rtc_set_alarm,
	.alarm_irq_enable = lpc32xx_rtc_alarm_irq_enable,
	};

	static int lpc32xx_rtc_probe(struct platform_device *pdev)
	{
	struct resource *res;
	struct lpc32xx_rtc *rtc;
	resource_size_t size;
	int rtcirq;
	u32 tmp;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
	dev_err(&pdev->dev, "Can't get memory resource\n");
	return -ENOENT;
	}

	rtcirq = platform_get_irq(pdev, 0);
	if (rtcirq < 0 \|\| rtcirq >= NR_IRQS) {
	dev_warn(&pdev->dev, "Can't get interrupt resource\n");
	rtcirq = -1;
	}

	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
	if (unlikely(!rtc)) {
	dev_err(&pdev->dev, "Can't allocate memory\n");
	return -ENOMEM;
	}
	rtc->irq = rtcirq;

	size = resource_size(res);

	if (!devm_request_mem_region(&pdev->dev, res->start, size,
	pdev->name)) {
	dev_err(&pdev->dev, "RTC registers are not free\n");
	return -EBUSY;
	}

	rtc->rtc_base = devm_ioremap(&pdev->dev, res->start, size);
	if (!rtc->rtc_base) {
	dev_err(&pdev->dev, "Can't map memory\n");
	return -ENOMEM;
	}

	spin_lock_init(&rtc->lock);

	/*
	* The RTC is on a separate power domain and can keep it's state
	* across a chip power cycle. If the RTC has never been previously
	* setup, then set it up now for the first time.
	*/
	tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL);
	if (rtc_readl(rtc, LPC32XX_RTC_KEY) != LPC32XX_RTC_KEY_ONSW_LOADVAL) {
	tmp &= ~(LPC32XX_RTC_CTRL_SW_RESET \|
	LPC32XX_RTC_CTRL_CNTR_DIS \|
	LPC32XX_RTC_CTRL_MATCH0 \|
	LPC32XX_RTC_CTRL_MATCH1 \|
	LPC32XX_RTC_CTRL_ONSW_MATCH0 \|
	LPC32XX_RTC_CTRL_ONSW_MATCH1 \|
	LPC32XX_RTC_CTRL_ONSW_FORCE_HI);
	rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp);

	/* Clear latched interrupt states */
	rtc_writel(rtc, LPC32XX_RTC_MATCH0, 0xFFFFFFFF);
	rtc_writel(rtc, LPC32XX_RTC_INTSTAT,
	LPC32XX_RTC_INTSTAT_MATCH0 \|
	LPC32XX_RTC_INTSTAT_MATCH1 \|
	LPC32XX_RTC_INTSTAT_ONSW);

	/* Write key value to RTC so it won't reload on reset */
	rtc_writel(rtc, LPC32XX_RTC_KEY,
	LPC32XX_RTC_KEY_ONSW_LOADVAL);
	} else {
	rtc_writel(rtc, LPC32XX_RTC_CTRL,
	tmp & ~LPC32XX_RTC_CTRL_MATCH0);
	}

	platform_set_drvdata(pdev, rtc);

	rtc->rtc = rtc_device_register(RTC_NAME, &pdev->dev, &lpc32xx_rtc_ops,
	THIS_MODULE);
	if (IS_ERR(rtc->rtc)) {
	dev_err(&pdev->dev, "Can't get RTC\n");
	platform_set_drvdata(pdev, NULL);
	return PTR_ERR(rtc->rtc);
	}

	/*
	* IRQ is enabled after device registration in case alarm IRQ
	* is pending upon suspend exit.
	*/
	if (rtc->irq >= 0) {
	if (devm_request_irq(&pdev->dev, rtc->irq,
	lpc32xx_rtc_alarm_interrupt,
	0, pdev->name, rtc) < 0) {
	dev_warn(&pdev->dev, "Can't request interrupt.\n");
	rtc->irq = -1;
	} else {
	device_init_wakeup(&pdev->dev, 1);
	}
	}

	return 0;
	}

	static int lpc32xx_rtc_remove(struct platform_device *pdev)
	{
	struct lpc32xx_rtc *rtc = platform_get_drvdata(pdev);

	if (rtc->irq >= 0)
	device_init_wakeup(&pdev->dev, 0);

	platform_set_drvdata(pdev, NULL);
	rtc_device_unregister(rtc->rtc);

	return 0;
	}

	#ifdef CONFIG_PM
	static int lpc32xx_rtc_suspend(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct lpc32xx_rtc *rtc = platform_get_drvdata(pdev);

	if (rtc->irq >= 0) {
	if (device_may_wakeup(&pdev->dev))
	enable_irq_wake(rtc->irq);
	else
	disable_irq_wake(rtc->irq);
	}

	return 0;
	}

	static int lpc32xx_rtc_resume(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct lpc32xx_rtc *rtc = platform_get_drvdata(pdev);

	if (rtc->irq >= 0 && device_may_wakeup(&pdev->dev))
	disable_irq_wake(rtc->irq);

	return 0;
	}

	/* Unconditionally disable the alarm */
	static int lpc32xx_rtc_freeze(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct lpc32xx_rtc *rtc = platform_get_drvdata(pdev);

	spin_lock_irq(&rtc->lock);

	rtc_writel(rtc, LPC32XX_RTC_CTRL,
	rtc_readl(rtc, LPC32XX_RTC_CTRL) &
	~LPC32XX_RTC_CTRL_MATCH0);

	spin_unlock_irq(&rtc->lock);

	return 0;
	}

	static int lpc32xx_rtc_thaw(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct lpc32xx_rtc *rtc = platform_get_drvdata(pdev);

	if (rtc->alarm_enabled) {
	spin_lock_irq(&rtc->lock);

	rtc_writel(rtc, LPC32XX_RTC_CTRL,
	rtc_readl(rtc, LPC32XX_RTC_CTRL) \|
	LPC32XX_RTC_CTRL_MATCH0);

	spin_unlock_irq(&rtc->lock);
	}

	return 0;
	}

	static const struct dev_pm_ops lpc32xx_rtc_pm_ops = {
	.suspend = lpc32xx_rtc_suspend,
	.resume = lpc32xx_rtc_resume,
	.freeze = lpc32xx_rtc_freeze,
	.thaw = lpc32xx_rtc_thaw,
	.restore = lpc32xx_rtc_resume
	};

	#define LPC32XX_RTC_PM_OPS (&lpc32xx_rtc_pm_ops)
	#else
	#define LPC32XX_RTC_PM_OPS NULL
	#endif

	#ifdef CONFIG_OF
	static const struct of_device_id lpc32xx_rtc_match[] = {
	{ .compatible = "nxp,lpc3220-rtc" },
	{ }
	};
	MODULE_DEVICE_TABLE(of, lpc32xx_rtc_match);
	#endif

	static struct platform_driver lpc32xx_rtc_driver = {
	.probe = lpc32xx_rtc_probe,
	.remove = lpc32xx_rtc_remove,
	.driver = {
	.name = RTC_NAME,
	.owner = THIS_MODULE,
	.pm = LPC32XX_RTC_PM_OPS,
	.of_match_table = of_match_ptr(lpc32xx_rtc_match),
	},
	};

	module_platform_driver(lpc32xx_rtc_driver);

	MODULE_AUTHOR("Kevin Wells <wellsk40@gmail.com");
	MODULE_DESCRIPTION("RTC driver for the LPC32xx SoC");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("platform:rtc-lpc32xx");