drivers/rtc/rtc-pxa.c - kernel/msm-4.19 - Gitiles

 /*
  * Real Time Clock interface for XScale PXA27x and PXA3xx
  *
  * Copyright (C) 2008 Robert Jarzmik
  *
  * 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.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; 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/platform_device.h>
 #include <linux/module.h>
 #include <linux/rtc.h>
 #include <linux/seq_file.h>
 #include <linux/interrupt.h>

 #include <asm/io.h>

 #define TIMER_FREQ		CLOCK_TICK_RATE
 #define RTC_DEF_DIVIDER		(32768 - 1)
 #define RTC_DEF_TRIM		0
 #define MAXFREQ_PERIODIC	1000

 /*
  * PXA Registers and bits definitions
  */
 #define RTSR_PICE	(1 << 15)	/* Periodic interrupt count enable */
 #define RTSR_PIALE	(1 << 14)	/* Periodic interrupt Alarm enable */
 #define RTSR_PIAL	(1 << 13)	/* Periodic interrupt detected */
 #define RTSR_SWALE2	(1 << 11)	/* RTC stopwatch alarm2 enable */
 #define RTSR_SWAL2	(1 << 10)	/* RTC stopwatch alarm2 detected */
 #define RTSR_SWALE1	(1 << 9)	/* RTC stopwatch alarm1 enable */
 #define RTSR_SWAL1	(1 << 8)	/* RTC stopwatch alarm1 detected */
 #define RTSR_RDALE2	(1 << 7)	/* RTC alarm2 enable */
 #define RTSR_RDAL2	(1 << 6)	/* RTC alarm2 detected */
 #define RTSR_RDALE1	(1 << 5)	/* RTC alarm1 enable */
 #define RTSR_RDAL1	(1 << 4)	/* RTC alarm1 detected */
 #define RTSR_HZE	(1 << 3)	/* HZ interrupt enable */
 #define RTSR_ALE	(1 << 2)	/* RTC alarm interrupt enable */
 #define RTSR_HZ		(1 << 1)	/* HZ rising-edge detected */
 #define RTSR_AL		(1 << 0)	/* RTC alarm detected */
 #define RTSR_TRIG_MASK	(RTSR_AL | RTSR_HZ | RTSR_RDAL1 | RTSR_RDAL2\
 			 | RTSR_SWAL1 | RTSR_SWAL2)
 #define RYxR_YEAR_S	9
 #define RYxR_YEAR_MASK	(0xfff << RYxR_YEAR_S)
 #define RYxR_MONTH_S	5
 #define RYxR_MONTH_MASK	(0xf << RYxR_MONTH_S)
 #define RYxR_DAY_MASK	0x1f
 #define RDxR_HOUR_S	12
 #define RDxR_HOUR_MASK	(0x1f << RDxR_HOUR_S)
 #define RDxR_MIN_S	6
 #define RDxR_MIN_MASK	(0x3f << RDxR_MIN_S)
 #define RDxR_SEC_MASK	0x3f

 #define RTSR		0x08
 #define RTTR		0x0c
 #define RDCR		0x10
 #define RYCR		0x14
 #define RDAR1		0x18
 #define RYAR1		0x1c
 #define RTCPICR		0x34
 #define PIAR		0x38

 #define rtc_readl(pxa_rtc, reg)	\
 	__raw_readl((pxa_rtc)->base + (reg))
 #define rtc_writel(pxa_rtc, reg, value)	\
 	__raw_writel((value), (pxa_rtc)->base + (reg))

 struct pxa_rtc {
 	struct resource	*ress;
 	void __iomem		*base;
 	int			irq_1Hz;
 	int			irq_Alrm;
 	struct rtc_device	*rtc;
 	spinlock_t		lock;		/* Protects this structure */
 	struct rtc_time		rtc_alarm;
 };

 static u32 ryxr_calc(struct rtc_time *tm)
 {
 	return ((tm->tm_year + 1900) << RYxR_YEAR_S)
 		| ((tm->tm_mon + 1) << RYxR_MONTH_S)
 		| tm->tm_mday;
 }

 static u32 rdxr_calc(struct rtc_time *tm)
 {
 	return (tm->tm_hour << RDxR_HOUR_S) | (tm->tm_min << RDxR_MIN_S)
 		| tm->tm_sec;
 }

 static void tm_calc(u32 rycr, u32 rdcr, struct rtc_time *tm)
 {
 	tm->tm_year = ((rycr & RYxR_YEAR_MASK) >> RYxR_YEAR_S) - 1900;
 	tm->tm_mon = (((rycr & RYxR_MONTH_MASK) >> RYxR_MONTH_S)) - 1;
 	tm->tm_mday = (rycr & RYxR_DAY_MASK);
 	tm->tm_hour = (rdcr & RDxR_HOUR_MASK) >> RDxR_HOUR_S;
 	tm->tm_min = (rdcr & RDxR_MIN_MASK) >> RDxR_MIN_S;
 	tm->tm_sec = rdcr & RDxR_SEC_MASK;
 }

 static void rtsr_clear_bits(struct pxa_rtc *pxa_rtc, u32 mask)
 {
 	u32 rtsr;

 	rtsr = rtc_readl(pxa_rtc, RTSR);
 	rtsr &= ~RTSR_TRIG_MASK;
 	rtsr &= ~mask;
 	rtc_writel(pxa_rtc, RTSR, rtsr);
 }

 static void rtsr_set_bits(struct pxa_rtc *pxa_rtc, u32 mask)
 {
 	u32 rtsr;

 	rtsr = rtc_readl(pxa_rtc, RTSR);
 	rtsr &= ~RTSR_TRIG_MASK;
 	rtsr |= mask;
 	rtc_writel(pxa_rtc, RTSR, rtsr);
 }

 static irqreturn_t pxa_rtc_irq(int irq, void *dev_id)
 {
 	struct platform_device *pdev = to_platform_device(dev_id);
 	struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev);
 	u32 rtsr;
 	unsigned long events = 0;

 	spin_lock(&pxa_rtc->lock);

 	/* clear interrupt sources */
 	rtsr = rtc_readl(pxa_rtc, RTSR);
 	rtc_writel(pxa_rtc, RTSR, rtsr);

 	/* temporary disable rtc interrupts */
 	rtsr_clear_bits(pxa_rtc, RTSR_RDALE1 | RTSR_PIALE | RTSR_HZE);

 	/* clear alarm interrupt if it has occurred */
 	if (rtsr & RTSR_RDAL1)
 		rtsr &= ~RTSR_RDALE1;

 	/* update irq data & counter */
 	if (rtsr & RTSR_RDAL1)
 		events |= RTC_AF | RTC_IRQF;
 	if (rtsr & RTSR_HZ)
 		events |= RTC_UF | RTC_IRQF;
 	if (rtsr & RTSR_PIAL)
 		events |= RTC_PF | RTC_IRQF;

 	rtc_update_irq(pxa_rtc->rtc, 1, events);

 	/* enable back rtc interrupts */
 	rtc_writel(pxa_rtc, RTSR, rtsr & ~RTSR_TRIG_MASK);

 	spin_unlock(&pxa_rtc->lock);
 	return IRQ_HANDLED;
 }

 static int pxa_rtc_open(struct device *dev)
 {
 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
 	int ret;

 	ret = request_irq(pxa_rtc->irq_1Hz, pxa_rtc_irq, IRQF_DISABLED,
 			  "rtc 1Hz", dev);
 	if (ret < 0) {
 		dev_err(dev, "can't get irq %i, err %d\n", pxa_rtc->irq_1Hz,
 			ret);
 		goto err_irq_1Hz;
 	}
 	ret = request_irq(pxa_rtc->irq_Alrm, pxa_rtc_irq, IRQF_DISABLED,
 			  "rtc Alrm", dev);
 	if (ret < 0) {
 		dev_err(dev, "can't get irq %i, err %d\n", pxa_rtc->irq_Alrm,
 			ret);
 		goto err_irq_Alrm;
 	}

 	return 0;

 err_irq_Alrm:
 	free_irq(pxa_rtc->irq_1Hz, dev);
 err_irq_1Hz:
 	return ret;
 }

 static void pxa_rtc_release(struct device *dev)
 {
 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);

 	spin_lock_irq(&pxa_rtc->lock);
 	rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_RDALE1 | RTSR_HZE);
 	spin_unlock_irq(&pxa_rtc->lock);

 	free_irq(pxa_rtc->irq_Alrm, dev);
 	free_irq(pxa_rtc->irq_1Hz, dev);
 }

 static int pxa_periodic_irq_set_freq(struct device *dev, int freq)
 {
 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
 	int period_ms;

 	if (freq < 1 || freq > MAXFREQ_PERIODIC)
 		return -EINVAL;

 	period_ms = 1000 / freq;
 	rtc_writel(pxa_rtc, PIAR, period_ms);

 	return 0;
 }

 static int pxa_periodic_irq_set_state(struct device *dev, int enabled)
 {
 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);

 	if (enabled)
 		rtsr_set_bits(pxa_rtc, RTSR_PIALE | RTSR_PICE);
 	else
 		rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_PICE);

 	return 0;
 }

 static int pxa_rtc_ioctl(struct device *dev, unsigned int cmd,
 		unsigned long arg)
 {
 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
 	int ret = 0;

 	spin_lock_irq(&pxa_rtc->lock);
 	switch (cmd) {
 	case RTC_AIE_OFF:
 		rtsr_clear_bits(pxa_rtc, RTSR_RDALE1);
 		break;
 	case RTC_AIE_ON:
 		rtsr_set_bits(pxa_rtc, RTSR_RDALE1);
 		break;
 	case RTC_UIE_OFF:
 		rtsr_clear_bits(pxa_rtc, RTSR_HZE);
 		break;
 	case RTC_UIE_ON:
 		rtsr_set_bits(pxa_rtc, RTSR_HZE);
 		break;
 	default:
 		ret = -ENOIOCTLCMD;
 	}

 	spin_unlock_irq(&pxa_rtc->lock);
 	return ret;
 }

 static int pxa_rtc_read_time(struct device *dev, struct rtc_time *tm)
 {
 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
 	u32 rycr, rdcr;

 	rycr = rtc_readl(pxa_rtc, RYCR);
 	rdcr = rtc_readl(pxa_rtc, RDCR);

 	tm_calc(rycr, rdcr, tm);
 	return 0;
 }

 static int pxa_rtc_set_time(struct device *dev, struct rtc_time *tm)
 {
 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);

 	rtc_writel(pxa_rtc, RYCR, ryxr_calc(tm));
 	rtc_writel(pxa_rtc, RDCR, rdxr_calc(tm));

 	return 0;
 }

 static int pxa_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 {
 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
 	u32 rtsr, ryar, rdar;

 	ryar = rtc_readl(pxa_rtc, RYAR1);
 	rdar = rtc_readl(pxa_rtc, RDAR1);
 	tm_calc(ryar, rdar, &alrm->time);

 	rtsr = rtc_readl(pxa_rtc, RTSR);
 	alrm->enabled = (rtsr & RTSR_RDALE1) ? 1 : 0;
 	alrm->pending = (rtsr & RTSR_RDAL1) ? 1 : 0;
 	return 0;
 }

 static int pxa_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 {
 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
 	u32 rtsr;

 	spin_lock_irq(&pxa_rtc->lock);

 	rtc_writel(pxa_rtc, RYAR1, ryxr_calc(&alrm->time));
 	rtc_writel(pxa_rtc, RDAR1, rdxr_calc(&alrm->time));

 	rtsr = rtc_readl(pxa_rtc, RTSR);
 	if (alrm->enabled)
 		rtsr |= RTSR_RDALE1;
 	else
 		rtsr &= ~RTSR_RDALE1;
 	rtc_writel(pxa_rtc, RTSR, rtsr);

 	spin_unlock_irq(&pxa_rtc->lock);

 	return 0;
 }

 static int pxa_rtc_proc(struct device *dev, struct seq_file *seq)
 {
 	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);

 	seq_printf(seq, "trim/divider\t: 0x%08x\n", rtc_readl(pxa_rtc, RTTR));
 	seq_printf(seq, "update_IRQ\t: %s\n",
 		   (rtc_readl(pxa_rtc, RTSR) & RTSR_HZE) ? "yes" : "no");
 	seq_printf(seq, "periodic_IRQ\t: %s\n",
 		   (rtc_readl(pxa_rtc, RTSR) & RTSR_PIALE) ? "yes" : "no");
 	seq_printf(seq, "periodic_freq\t: %u\n", rtc_readl(pxa_rtc, PIAR));

 	return 0;
 }

 static const struct rtc_class_ops pxa_rtc_ops = {
 	.open = pxa_rtc_open,
 	.release = pxa_rtc_release,
 	.ioctl = pxa_rtc_ioctl,
 	.read_time = pxa_rtc_read_time,
 	.set_time = pxa_rtc_set_time,
 	.read_alarm = pxa_rtc_read_alarm,
 	.set_alarm = pxa_rtc_set_alarm,
 	.proc = pxa_rtc_proc,
 	.irq_set_state = pxa_periodic_irq_set_state,
 	.irq_set_freq = pxa_periodic_irq_set_freq,
 };

 static int __devinit pxa_rtc_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct pxa_rtc *pxa_rtc;
 	int ret;
 	u32 rttr;

 	ret = -ENOMEM;
 	pxa_rtc = kzalloc(sizeof(struct pxa_rtc), GFP_KERNEL);
 	if (!pxa_rtc)
 		goto err_alloc;

 	ret = -ENXIO;
 	pxa_rtc->ress = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!pxa_rtc->ress) {
 		dev_err(dev, "No I/O memory resource defined\n");
 		goto err_ress;
 	}

 	pxa_rtc->irq_1Hz = platform_get_irq(pdev, 0);
 	if (pxa_rtc->irq_1Hz < 0) {
 		dev_err(dev, "No 1Hz IRQ resource defined\n");
 		goto err_ress;
 	}
 	pxa_rtc->irq_Alrm = platform_get_irq(pdev, 1);
 	if (pxa_rtc->irq_Alrm < 0) {
 		dev_err(dev, "No alarm IRQ resource defined\n");
 		goto err_ress;
 	}

 	pxa_rtc->rtc = rtc_device_register(pdev->name, &pdev->dev, &pxa_rtc_ops,
 					   THIS_MODULE);
 	ret = PTR_ERR(pxa_rtc->rtc);
 	if (IS_ERR(pxa_rtc->rtc)) {
 		dev_err(dev, "Failed to register RTC device -> %d\n", ret);
 		goto err_rtc_reg;
 	}

 	spin_lock_init(&pxa_rtc->lock);
 	platform_set_drvdata(pdev, pxa_rtc);

 	ret = -ENOMEM;
 	pxa_rtc->base = ioremap(pxa_rtc->ress->start,
 				pxa_rtc->ress->end - pxa_rtc->ress->start + 1);
 	if (!pxa_rtc->base) {
 		dev_err(&pdev->dev, "Unable to map pxa RTC I/O memory\n");
 		goto err_map;
 	}

 	/*
 	 * If the clock divider is uninitialized then reset it to the
 	 * default value to get the 1Hz clock.
 	 */
 	if (rtc_readl(pxa_rtc, RTTR) == 0) {
 		rttr = RTC_DEF_DIVIDER + (RTC_DEF_TRIM << 16);
 		rtc_writel(pxa_rtc, RTTR, rttr);
 		dev_warn(dev, "warning: initializing default clock"
 			 " divider/trim value\n");
 	}

 	rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_RDALE1 | RTSR_HZE);
 	device_init_wakeup(dev, 1);

 	return 0;

 err_map:
 	platform_set_drvdata(pdev, NULL);
 	rtc_device_unregister(pxa_rtc->rtc);
 err_rtc_reg:
 err_ress:
 	kfree(pxa_rtc);
 err_alloc:
 	return ret;
 }

 static int __devexit pxa_rtc_remove(struct platform_device *pdev)
 {
 	struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev);

 	spin_lock_irq(&pxa_rtc->lock);
 	iounmap(pxa_rtc->base);
 	pxa_rtc->base = NULL;
 	platform_set_drvdata(pdev, NULL);
 	spin_unlock_irq(&pxa_rtc->lock);

 	rtc_device_unregister(pxa_rtc->rtc);
 	kfree(pxa_rtc);

 	return 0;
 }

 #ifdef CONFIG_PM
 static int pxa_rtc_suspend(struct platform_device *pdev, pm_message_t state)
 {
 	struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev);

 	if (device_may_wakeup(&pdev->dev))
 		enable_irq_wake(pxa_rtc->irq_Alrm);
 	return 0;
 }

 static int pxa_rtc_resume(struct platform_device *pdev)
 {
 	struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev);

 	if (device_may_wakeup(&pdev->dev))
 		disable_irq_wake(pxa_rtc->irq_Alrm);
 	return 0;
 }
 #else
 #define pxa_rtc_suspend	NULL
 #define pxa_rtc_resume	NULL
 #endif

 static struct platform_driver pxa_rtc_driver = {
 	.probe		= pxa_rtc_probe,
 	.remove		= __exit_p(pxa_rtc_remove),
 	.suspend	= pxa_rtc_suspend,
 	.resume		= pxa_rtc_resume,
 	.driver		= {
 		.name		= "pxa-rtc",
 	},
 };

 static int __init pxa_rtc_init(void)
 {
 	if (cpu_is_pxa27x() || cpu_is_pxa3xx())
 		return platform_driver_register(&pxa_rtc_driver);

 	return -ENODEV;
 }

 static void __exit pxa_rtc_exit(void)
 {
 	platform_driver_unregister(&pxa_rtc_driver);
 }

 module_init(pxa_rtc_init);
 module_exit(pxa_rtc_exit);

 MODULE_AUTHOR("Robert Jarzmik");
 MODULE_DESCRIPTION("PXA27x/PXA3xx Realtime Clock Driver (RTC)");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:pxa-rtc");
	/*
	* Real Time Clock interface for XScale PXA27x and PXA3xx
	*
	* Copyright (C) 2008 Robert Jarzmik
	*
	* 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.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; 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/platform_device.h>
	#include <linux/module.h>
	#include <linux/rtc.h>
	#include <linux/seq_file.h>
	#include <linux/interrupt.h>

	#include <asm/io.h>

	#define TIMER_FREQ CLOCK_TICK_RATE
	#define RTC_DEF_DIVIDER (32768 - 1)
	#define RTC_DEF_TRIM 0
	#define MAXFREQ_PERIODIC 1000

	/*
	* PXA Registers and bits definitions
	*/
	#define RTSR_PICE (1 << 15) /* Periodic interrupt count enable */
	#define RTSR_PIALE (1 << 14) /* Periodic interrupt Alarm enable */
	#define RTSR_PIAL (1 << 13) /* Periodic interrupt detected */
	#define RTSR_SWALE2 (1 << 11) /* RTC stopwatch alarm2 enable */
	#define RTSR_SWAL2 (1 << 10) /* RTC stopwatch alarm2 detected */
	#define RTSR_SWALE1 (1 << 9) /* RTC stopwatch alarm1 enable */
	#define RTSR_SWAL1 (1 << 8) /* RTC stopwatch alarm1 detected */
	#define RTSR_RDALE2 (1 << 7) /* RTC alarm2 enable */
	#define RTSR_RDAL2 (1 << 6) /* RTC alarm2 detected */
	#define RTSR_RDALE1 (1 << 5) /* RTC alarm1 enable */
	#define RTSR_RDAL1 (1 << 4) /* RTC alarm1 detected */
	#define RTSR_HZE (1 << 3) /* HZ interrupt enable */
	#define RTSR_ALE (1 << 2) /* RTC alarm interrupt enable */
	#define RTSR_HZ (1 << 1) /* HZ rising-edge detected */
	#define RTSR_AL (1 << 0) /* RTC alarm detected */
	#define RTSR_TRIG_MASK (RTSR_AL \| RTSR_HZ \| RTSR_RDAL1 \| RTSR_RDAL2\
	\| RTSR_SWAL1 \| RTSR_SWAL2)
	#define RYxR_YEAR_S 9
	#define RYxR_YEAR_MASK (0xfff << RYxR_YEAR_S)
	#define RYxR_MONTH_S 5
	#define RYxR_MONTH_MASK (0xf << RYxR_MONTH_S)
	#define RYxR_DAY_MASK 0x1f
	#define RDxR_HOUR_S 12
	#define RDxR_HOUR_MASK (0x1f << RDxR_HOUR_S)
	#define RDxR_MIN_S 6
	#define RDxR_MIN_MASK (0x3f << RDxR_MIN_S)
	#define RDxR_SEC_MASK 0x3f

	#define RTSR 0x08
	#define RTTR 0x0c
	#define RDCR 0x10
	#define RYCR 0x14
	#define RDAR1 0x18
	#define RYAR1 0x1c
	#define RTCPICR 0x34
	#define PIAR 0x38

	#define rtc_readl(pxa_rtc, reg) \
	__raw_readl((pxa_rtc)->base + (reg))
	#define rtc_writel(pxa_rtc, reg, value) \
	__raw_writel((value), (pxa_rtc)->base + (reg))

	struct pxa_rtc {
	struct resource *ress;
	void __iomem *base;
	int irq_1Hz;
	int irq_Alrm;
	struct rtc_device *rtc;
	spinlock_t lock; /* Protects this structure */
	struct rtc_time rtc_alarm;
	};

	static u32 ryxr_calc(struct rtc_time *tm)
	{
	return ((tm->tm_year + 1900) << RYxR_YEAR_S)
	\| ((tm->tm_mon + 1) << RYxR_MONTH_S)
	\| tm->tm_mday;
	}

	static u32 rdxr_calc(struct rtc_time *tm)
	{
	return (tm->tm_hour << RDxR_HOUR_S) \| (tm->tm_min << RDxR_MIN_S)
	\| tm->tm_sec;
	}

	static void tm_calc(u32 rycr, u32 rdcr, struct rtc_time *tm)
	{
	tm->tm_year = ((rycr & RYxR_YEAR_MASK) >> RYxR_YEAR_S) - 1900;
	tm->tm_mon = (((rycr & RYxR_MONTH_MASK) >> RYxR_MONTH_S)) - 1;
	tm->tm_mday = (rycr & RYxR_DAY_MASK);
	tm->tm_hour = (rdcr & RDxR_HOUR_MASK) >> RDxR_HOUR_S;
	tm->tm_min = (rdcr & RDxR_MIN_MASK) >> RDxR_MIN_S;
	tm->tm_sec = rdcr & RDxR_SEC_MASK;
	}

	static void rtsr_clear_bits(struct pxa_rtc *pxa_rtc, u32 mask)
	{
	u32 rtsr;

	rtsr = rtc_readl(pxa_rtc, RTSR);
	rtsr &= ~RTSR_TRIG_MASK;
	rtsr &= ~mask;
	rtc_writel(pxa_rtc, RTSR, rtsr);
	}

	static void rtsr_set_bits(struct pxa_rtc *pxa_rtc, u32 mask)
	{
	u32 rtsr;

	rtsr = rtc_readl(pxa_rtc, RTSR);
	rtsr &= ~RTSR_TRIG_MASK;
	rtsr \|= mask;
	rtc_writel(pxa_rtc, RTSR, rtsr);
	}

	static irqreturn_t pxa_rtc_irq(int irq, void *dev_id)
	{
	struct platform_device *pdev = to_platform_device(dev_id);
	struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev);
	u32 rtsr;
	unsigned long events = 0;

	spin_lock(&pxa_rtc->lock);

	/* clear interrupt sources */
	rtsr = rtc_readl(pxa_rtc, RTSR);
	rtc_writel(pxa_rtc, RTSR, rtsr);

	/* temporary disable rtc interrupts */
	rtsr_clear_bits(pxa_rtc, RTSR_RDALE1 \| RTSR_PIALE \| RTSR_HZE);

	/* clear alarm interrupt if it has occurred */
	if (rtsr & RTSR_RDAL1)
	rtsr &= ~RTSR_RDALE1;

	/* update irq data & counter */
	if (rtsr & RTSR_RDAL1)
	events \|= RTC_AF \| RTC_IRQF;
	if (rtsr & RTSR_HZ)
	events \|= RTC_UF \| RTC_IRQF;
	if (rtsr & RTSR_PIAL)
	events \|= RTC_PF \| RTC_IRQF;

	rtc_update_irq(pxa_rtc->rtc, 1, events);

	/* enable back rtc interrupts */
	rtc_writel(pxa_rtc, RTSR, rtsr & ~RTSR_TRIG_MASK);

	spin_unlock(&pxa_rtc->lock);
	return IRQ_HANDLED;
	}

	static int pxa_rtc_open(struct device *dev)
	{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
	int ret;

	ret = request_irq(pxa_rtc->irq_1Hz, pxa_rtc_irq, IRQF_DISABLED,
	"rtc 1Hz", dev);
	if (ret < 0) {
	dev_err(dev, "can't get irq %i, err %d\n", pxa_rtc->irq_1Hz,
	ret);
	goto err_irq_1Hz;
	}
	ret = request_irq(pxa_rtc->irq_Alrm, pxa_rtc_irq, IRQF_DISABLED,
	"rtc Alrm", dev);
	if (ret < 0) {
	dev_err(dev, "can't get irq %i, err %d\n", pxa_rtc->irq_Alrm,
	ret);
	goto err_irq_Alrm;
	}

	return 0;

	err_irq_Alrm:
	free_irq(pxa_rtc->irq_1Hz, dev);
	err_irq_1Hz:
	return ret;
	}

	static void pxa_rtc_release(struct device *dev)
	{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);

	spin_lock_irq(&pxa_rtc->lock);
	rtsr_clear_bits(pxa_rtc, RTSR_PIALE \| RTSR_RDALE1 \| RTSR_HZE);
	spin_unlock_irq(&pxa_rtc->lock);

	free_irq(pxa_rtc->irq_Alrm, dev);
	free_irq(pxa_rtc->irq_1Hz, dev);
	}

	static int pxa_periodic_irq_set_freq(struct device *dev, int freq)
	{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
	int period_ms;

	if (freq < 1 \|\| freq > MAXFREQ_PERIODIC)
	return -EINVAL;

	period_ms = 1000 / freq;
	rtc_writel(pxa_rtc, PIAR, period_ms);

	return 0;
	}

	static int pxa_periodic_irq_set_state(struct device *dev, int enabled)
	{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);

	if (enabled)
	rtsr_set_bits(pxa_rtc, RTSR_PIALE \| RTSR_PICE);
	else
	rtsr_clear_bits(pxa_rtc, RTSR_PIALE \| RTSR_PICE);

	return 0;
	}

	static int pxa_rtc_ioctl(struct device *dev, unsigned int cmd,
	unsigned long arg)
	{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
	int ret = 0;

	spin_lock_irq(&pxa_rtc->lock);
	switch (cmd) {
	case RTC_AIE_OFF:
	rtsr_clear_bits(pxa_rtc, RTSR_RDALE1);
	break;
	case RTC_AIE_ON:
	rtsr_set_bits(pxa_rtc, RTSR_RDALE1);
	break;
	case RTC_UIE_OFF:
	rtsr_clear_bits(pxa_rtc, RTSR_HZE);
	break;
	case RTC_UIE_ON:
	rtsr_set_bits(pxa_rtc, RTSR_HZE);
	break;
	default:
	ret = -ENOIOCTLCMD;
	}

	spin_unlock_irq(&pxa_rtc->lock);
	return ret;
	}

	static int pxa_rtc_read_time(struct device dev, struct rtc_time tm)
	{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
	u32 rycr, rdcr;

	rycr = rtc_readl(pxa_rtc, RYCR);
	rdcr = rtc_readl(pxa_rtc, RDCR);

	tm_calc(rycr, rdcr, tm);
	return 0;
	}

	static int pxa_rtc_set_time(struct device dev, struct rtc_time tm)
	{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);

	rtc_writel(pxa_rtc, RYCR, ryxr_calc(tm));
	rtc_writel(pxa_rtc, RDCR, rdxr_calc(tm));

	return 0;
	}

	static int pxa_rtc_read_alarm(struct device dev, struct rtc_wkalrm alrm)
	{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
	u32 rtsr, ryar, rdar;

	ryar = rtc_readl(pxa_rtc, RYAR1);
	rdar = rtc_readl(pxa_rtc, RDAR1);
	tm_calc(ryar, rdar, &alrm->time);

	rtsr = rtc_readl(pxa_rtc, RTSR);
	alrm->enabled = (rtsr & RTSR_RDALE1) ? 1 : 0;
	alrm->pending = (rtsr & RTSR_RDAL1) ? 1 : 0;
	return 0;
	}

	static int pxa_rtc_set_alarm(struct device dev, struct rtc_wkalrm alrm)
	{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);
	u32 rtsr;

	spin_lock_irq(&pxa_rtc->lock);

	rtc_writel(pxa_rtc, RYAR1, ryxr_calc(&alrm->time));
	rtc_writel(pxa_rtc, RDAR1, rdxr_calc(&alrm->time));

	rtsr = rtc_readl(pxa_rtc, RTSR);
	if (alrm->enabled)
	rtsr \|= RTSR_RDALE1;
	else
	rtsr &= ~RTSR_RDALE1;
	rtc_writel(pxa_rtc, RTSR, rtsr);

	spin_unlock_irq(&pxa_rtc->lock);

	return 0;
	}

	static int pxa_rtc_proc(struct device dev, struct seq_file seq)
	{
	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev);

	seq_printf(seq, "trim/divider\t: 0x%08x\n", rtc_readl(pxa_rtc, RTTR));
	seq_printf(seq, "update_IRQ\t: %s\n",
	(rtc_readl(pxa_rtc, RTSR) & RTSR_HZE) ? "yes" : "no");
	seq_printf(seq, "periodic_IRQ\t: %s\n",
	(rtc_readl(pxa_rtc, RTSR) & RTSR_PIALE) ? "yes" : "no");
	seq_printf(seq, "periodic_freq\t: %u\n", rtc_readl(pxa_rtc, PIAR));

	return 0;
	}

	static const struct rtc_class_ops pxa_rtc_ops = {
	.open = pxa_rtc_open,
	.release = pxa_rtc_release,
	.ioctl = pxa_rtc_ioctl,
	.read_time = pxa_rtc_read_time,
	.set_time = pxa_rtc_set_time,
	.read_alarm = pxa_rtc_read_alarm,
	.set_alarm = pxa_rtc_set_alarm,
	.proc = pxa_rtc_proc,
	.irq_set_state = pxa_periodic_irq_set_state,
	.irq_set_freq = pxa_periodic_irq_set_freq,
	};

	static int __devinit pxa_rtc_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	struct pxa_rtc *pxa_rtc;
	int ret;
	u32 rttr;

	ret = -ENOMEM;
	pxa_rtc = kzalloc(sizeof(struct pxa_rtc), GFP_KERNEL);
	if (!pxa_rtc)
	goto err_alloc;

	ret = -ENXIO;
	pxa_rtc->ress = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!pxa_rtc->ress) {
	dev_err(dev, "No I/O memory resource defined\n");
	goto err_ress;
	}

	pxa_rtc->irq_1Hz = platform_get_irq(pdev, 0);
	if (pxa_rtc->irq_1Hz < 0) {
	dev_err(dev, "No 1Hz IRQ resource defined\n");
	goto err_ress;
	}
	pxa_rtc->irq_Alrm = platform_get_irq(pdev, 1);
	if (pxa_rtc->irq_Alrm < 0) {
	dev_err(dev, "No alarm IRQ resource defined\n");
	goto err_ress;
	}

	pxa_rtc->rtc = rtc_device_register(pdev->name, &pdev->dev, &pxa_rtc_ops,
	THIS_MODULE);
	ret = PTR_ERR(pxa_rtc->rtc);
	if (IS_ERR(pxa_rtc->rtc)) {
	dev_err(dev, "Failed to register RTC device -> %d\n", ret);
	goto err_rtc_reg;
	}

	spin_lock_init(&pxa_rtc->lock);
	platform_set_drvdata(pdev, pxa_rtc);

	ret = -ENOMEM;
	pxa_rtc->base = ioremap(pxa_rtc->ress->start,
	pxa_rtc->ress->end - pxa_rtc->ress->start + 1);
	if (!pxa_rtc->base) {
	dev_err(&pdev->dev, "Unable to map pxa RTC I/O memory\n");
	goto err_map;
	}

	/*
	* If the clock divider is uninitialized then reset it to the
	* default value to get the 1Hz clock.
	*/
	if (rtc_readl(pxa_rtc, RTTR) == 0) {
	rttr = RTC_DEF_DIVIDER + (RTC_DEF_TRIM << 16);
	rtc_writel(pxa_rtc, RTTR, rttr);
	dev_warn(dev, "warning: initializing default clock"
	" divider/trim value\n");
	}

	rtsr_clear_bits(pxa_rtc, RTSR_PIALE \| RTSR_RDALE1 \| RTSR_HZE);
	device_init_wakeup(dev, 1);

	return 0;

	err_map:
	platform_set_drvdata(pdev, NULL);
	rtc_device_unregister(pxa_rtc->rtc);
	err_rtc_reg:
	err_ress:
	kfree(pxa_rtc);
	err_alloc:
	return ret;
	}

	static int __devexit pxa_rtc_remove(struct platform_device *pdev)
	{
	struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev);

	spin_lock_irq(&pxa_rtc->lock);
	iounmap(pxa_rtc->base);
	pxa_rtc->base = NULL;
	platform_set_drvdata(pdev, NULL);
	spin_unlock_irq(&pxa_rtc->lock);

	rtc_device_unregister(pxa_rtc->rtc);
	kfree(pxa_rtc);

	return 0;
	}

	#ifdef CONFIG_PM
	static int pxa_rtc_suspend(struct platform_device *pdev, pm_message_t state)
	{
	struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev);

	if (device_may_wakeup(&pdev->dev))
	enable_irq_wake(pxa_rtc->irq_Alrm);
	return 0;
	}

	static int pxa_rtc_resume(struct platform_device *pdev)
	{
	struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev);

	if (device_may_wakeup(&pdev->dev))
	disable_irq_wake(pxa_rtc->irq_Alrm);
	return 0;
	}
	#else
	#define pxa_rtc_suspend NULL
	#define pxa_rtc_resume NULL
	#endif

	static struct platform_driver pxa_rtc_driver = {
	.probe = pxa_rtc_probe,
	.remove = __exit_p(pxa_rtc_remove),
	.suspend = pxa_rtc_suspend,
	.resume = pxa_rtc_resume,
	.driver = {
	.name = "pxa-rtc",
	},
	};

	static int __init pxa_rtc_init(void)
	{
	if (cpu_is_pxa27x() \|\| cpu_is_pxa3xx())
	return platform_driver_register(&pxa_rtc_driver);

	return -ENODEV;
	}

	static void __exit pxa_rtc_exit(void)
	{
	platform_driver_unregister(&pxa_rtc_driver);
	}

	module_init(pxa_rtc_init);
	module_exit(pxa_rtc_exit);

	MODULE_AUTHOR("Robert Jarzmik");
	MODULE_DESCRIPTION("PXA27x/PXA3xx Realtime Clock Driver (RTC)");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("platform:pxa-rtc");