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

 /*
  * SuperH On-Chip RTC Support
  *
  * Copyright (C) 2006  Paul Mundt
  *
  * Based on the old arch/sh/kernel/cpu/rtc.c by:
  *
  *  Copyright (C) 2000  Philipp Rumpf <prumpf@tux.org>
  *  Copyright (C) 1999  Tetsuya Okada & Niibe Yutaka
  *
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  */
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/bcd.h>
 #include <linux/rtc.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
 #include <linux/seq_file.h>
 #include <linux/interrupt.h>
 #include <linux/spinlock.h>
 #include <asm/io.h>

 #ifdef CONFIG_CPU_SH3
 #define rtc_reg_size		sizeof(u16)
 #define RTC_BIT_INVERTED	0	/* No bug on SH7708, SH7709A */
 #elif defined(CONFIG_CPU_SH4)
 #define rtc_reg_size		sizeof(u32)
 #define RTC_BIT_INVERTED	0x40	/* bug on SH7750, SH7750S */
 #endif

 #define RTC_REG(r)	((r) * rtc_reg_size)

 #define R64CNT  	RTC_REG(0)
 #define RSECCNT 	RTC_REG(1)
 #define RMINCNT 	RTC_REG(2)
 #define RHRCNT  	RTC_REG(3)
 #define RWKCNT  	RTC_REG(4)
 #define RDAYCNT 	RTC_REG(5)
 #define RMONCNT 	RTC_REG(6)
 #define RYRCNT  	RTC_REG(7)
 #define RSECAR  	RTC_REG(8)
 #define RMINAR  	RTC_REG(9)
 #define RHRAR   	RTC_REG(10)
 #define RWKAR   	RTC_REG(11)
 #define RDAYAR  	RTC_REG(12)
 #define RMONAR  	RTC_REG(13)
 #define RCR1    	RTC_REG(14)
 #define RCR2    	RTC_REG(15)

 /* RCR1 Bits */
 #define RCR1_CF		0x80	/* Carry Flag             */
 #define RCR1_CIE	0x10	/* Carry Interrupt Enable */
 #define RCR1_AIE	0x08	/* Alarm Interrupt Enable */
 #define RCR1_AF		0x01	/* Alarm Flag             */

 /* RCR2 Bits */
 #define RCR2_PEF	0x80	/* PEriodic interrupt Flag */
 #define RCR2_PESMASK	0x70	/* Periodic interrupt Set  */
 #define RCR2_RTCEN	0x08	/* ENable RTC              */
 #define RCR2_ADJ	0x04	/* ADJustment (30-second)  */
 #define RCR2_RESET	0x02	/* Reset bit               */
 #define RCR2_START	0x01	/* Start bit               */

 struct sh_rtc {
 	void __iomem *regbase;
 	unsigned long regsize;
 	struct resource *res;
 	unsigned int alarm_irq, periodic_irq, carry_irq;
 	struct rtc_device *rtc_dev;
 	spinlock_t lock;
 };

 static irqreturn_t sh_rtc_interrupt(int irq, void *id)
 {
 	struct platform_device *pdev = id;
 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
 	unsigned int tmp, events = 0;

 	spin_lock(&rtc->lock);

 	tmp = readb(rtc->regbase + RCR1);

 	if (tmp & RCR1_AF)
 		events |= RTC_AF | RTC_IRQF;

 	tmp &= ~(RCR1_CF | RCR1_AF);

 	writeb(tmp, rtc->regbase + RCR1);

 	rtc_update_irq(&rtc->rtc_dev->class_dev, 1, events);

 	spin_unlock(&rtc->lock);

 	return IRQ_HANDLED;
 }

 static irqreturn_t sh_rtc_periodic(int irq, void *id)
 {
 	struct sh_rtc *rtc = dev_get_drvdata(id);

 	spin_lock(&rtc->lock);

 	rtc_update_irq(&rtc->rtc_dev->class_dev, 1, RTC_PF | RTC_IRQF);

 	spin_unlock(&rtc->lock);

 	return IRQ_HANDLED;
 }

 static inline void sh_rtc_setpie(struct device *dev, unsigned int enable)
 {
 	struct sh_rtc *rtc = dev_get_drvdata(dev);
 	unsigned int tmp;

 	spin_lock_irq(&rtc->lock);

 	tmp = readb(rtc->regbase + RCR2);

 	if (enable) {
 		tmp &= ~RCR2_PESMASK;
 		tmp |= RCR2_PEF | (2 << 4);
 	} else
 		tmp &= ~(RCR2_PESMASK | RCR2_PEF);

 	writeb(tmp, rtc->regbase + RCR2);

 	spin_unlock_irq(&rtc->lock);
 }

 static inline void sh_rtc_setaie(struct device *dev, unsigned int enable)
 {
 	struct sh_rtc *rtc = dev_get_drvdata(dev);
 	unsigned int tmp;

 	spin_lock_irq(&rtc->lock);

 	tmp = readb(rtc->regbase + RCR1);

 	if (enable)
 		tmp |= RCR1_AIE;
 	else
 		tmp &= ~RCR1_AIE;

 	writeb(tmp, rtc->regbase + RCR1);

 	spin_unlock_irq(&rtc->lock);
 }

 static int sh_rtc_open(struct device *dev)
 {
 	struct sh_rtc *rtc = dev_get_drvdata(dev);
 	unsigned int tmp;
 	int ret;

 	tmp = readb(rtc->regbase + RCR1);
 	tmp &= ~RCR1_CF;
 	tmp |= RCR1_CIE;
 	writeb(tmp, rtc->regbase + RCR1);

 	ret = request_irq(rtc->periodic_irq, sh_rtc_periodic, IRQF_DISABLED,
 			  "sh-rtc period", dev);
 	if (unlikely(ret)) {
 		dev_err(dev, "request period IRQ failed with %d, IRQ %d\n",
 			ret, rtc->periodic_irq);
 		return ret;
 	}

 	ret = request_irq(rtc->carry_irq, sh_rtc_interrupt, IRQF_DISABLED,
 			  "sh-rtc carry", dev);
 	if (unlikely(ret)) {
 		dev_err(dev, "request carry IRQ failed with %d, IRQ %d\n",
 			ret, rtc->carry_irq);
 		free_irq(rtc->periodic_irq, dev);
 		goto err_bad_carry;
 	}

 	ret = request_irq(rtc->alarm_irq, sh_rtc_interrupt, IRQF_DISABLED,
 			  "sh-rtc alarm", dev);
 	if (unlikely(ret)) {
 		dev_err(dev, "request alarm IRQ failed with %d, IRQ %d\n",
 			ret, rtc->alarm_irq);
 		goto err_bad_alarm;
 	}

 	return 0;

 err_bad_alarm:
 	free_irq(rtc->carry_irq, dev);
 err_bad_carry:
 	free_irq(rtc->periodic_irq, dev);

 	return ret;
 }

 static void sh_rtc_release(struct device *dev)
 {
 	struct sh_rtc *rtc = dev_get_drvdata(dev);

 	sh_rtc_setpie(dev, 0);

 	free_irq(rtc->periodic_irq, dev);
 	free_irq(rtc->carry_irq, dev);
 	free_irq(rtc->alarm_irq, dev);
 }

 static int sh_rtc_proc(struct device *dev, struct seq_file *seq)
 {
 	struct sh_rtc *rtc = dev_get_drvdata(dev);
 	unsigned int tmp;

 	tmp = readb(rtc->regbase + RCR1);
 	seq_printf(seq, "alarm_IRQ\t: %s\n",
 		   (tmp & RCR1_AIE) ? "yes" : "no");
 	seq_printf(seq, "carry_IRQ\t: %s\n",
 		   (tmp & RCR1_CIE) ? "yes" : "no");

 	tmp = readb(rtc->regbase + RCR2);
 	seq_printf(seq, "periodic_IRQ\t: %s\n",
 		   (tmp & RCR2_PEF) ? "yes" : "no");

 	return 0;
 }

 static int sh_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
 {
 	unsigned int ret = -ENOIOCTLCMD;

 	switch (cmd) {
 	case RTC_PIE_OFF:
 	case RTC_PIE_ON:
 		sh_rtc_setpie(dev, cmd == RTC_PIE_ON);
 		ret = 0;
 		break;
 	case RTC_AIE_OFF:
 	case RTC_AIE_ON:
 		sh_rtc_setaie(dev, cmd == RTC_AIE_ON);
 		ret = 0;
 		break;
 	}

 	return ret;
 }

 static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
 	unsigned int sec128, sec2, yr, yr100, cf_bit;

 	do {
 		unsigned int tmp;

 		spin_lock_irq(&rtc->lock);

 		tmp = readb(rtc->regbase + RCR1);
 		tmp &= ~RCR1_CF; /* Clear CF-bit */
 		tmp |= RCR1_CIE;
 		writeb(tmp, rtc->regbase + RCR1);

 		sec128 = readb(rtc->regbase + R64CNT);

 		tm->tm_sec	= BCD2BIN(readb(rtc->regbase + RSECCNT));
 		tm->tm_min	= BCD2BIN(readb(rtc->regbase + RMINCNT));
 		tm->tm_hour	= BCD2BIN(readb(rtc->regbase + RHRCNT));
 		tm->tm_wday	= BCD2BIN(readb(rtc->regbase + RWKCNT));
 		tm->tm_mday	= BCD2BIN(readb(rtc->regbase + RDAYCNT));
 		tm->tm_mon	= BCD2BIN(readb(rtc->regbase + RMONCNT));

 #if defined(CONFIG_CPU_SH4)
 		yr  = readw(rtc->regbase + RYRCNT);
 		yr100 = BCD2BIN(yr >> 8);
 		yr &= 0xff;
 #else
 		yr  = readb(rtc->regbase + RYRCNT);
 		yr100 = BCD2BIN((yr == 0x99) ? 0x19 : 0x20);
 #endif

 		tm->tm_year = (yr100 * 100 + BCD2BIN(yr)) - 1900;

 		sec2 = readb(rtc->regbase + R64CNT);
 		cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF;

 		spin_unlock_irq(&rtc->lock);
 	} while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0);

 #if RTC_BIT_INVERTED != 0
 	if ((sec128 & RTC_BIT_INVERTED))
 		tm->tm_sec--;
 #endif

 	dev_dbg(&dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
 		"mday=%d, mon=%d, year=%d, wday=%d\n",
 		__FUNCTION__,
 		tm->tm_sec, tm->tm_min, tm->tm_hour,
 		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);

 	if (rtc_valid_tm(tm) < 0)
 		dev_err(dev, "invalid date\n");

 	return 0;
 }

 static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct sh_rtc *rtc = platform_get_drvdata(pdev);
 	unsigned int tmp;
 	int year;

 	spin_lock_irq(&rtc->lock);

 	/* Reset pre-scaler & stop RTC */
 	tmp = readb(rtc->regbase + RCR2);
 	tmp |= RCR2_RESET;
 	writeb(tmp, rtc->regbase + RCR2);

 	writeb(BIN2BCD(tm->tm_sec),  rtc->regbase + RSECCNT);
 	writeb(BIN2BCD(tm->tm_min),  rtc->regbase + RMINCNT);
 	writeb(BIN2BCD(tm->tm_hour), rtc->regbase + RHRCNT);
 	writeb(BIN2BCD(tm->tm_wday), rtc->regbase + RWKCNT);
 	writeb(BIN2BCD(tm->tm_mday), rtc->regbase + RDAYCNT);
 	writeb(BIN2BCD(tm->tm_mon),  rtc->regbase + RMONCNT);

 #ifdef CONFIG_CPU_SH3
 	year = tm->tm_year % 100;
 	writeb(BIN2BCD(year), rtc->regbase + RYRCNT);
 #else
 	year = (BIN2BCD((tm->tm_year + 1900) / 100) << 8) |
 		BIN2BCD(tm->tm_year % 100);
 	writew(year, rtc->regbase + RYRCNT);
 #endif

 	/* Start RTC */
 	tmp = readb(rtc->regbase + RCR2);
 	tmp &= ~RCR2_RESET;
 	tmp |= RCR2_RTCEN | RCR2_START;
 	writeb(tmp, rtc->regbase + RCR2);

 	spin_unlock_irq(&rtc->lock);

 	return 0;
 }

 static struct rtc_class_ops sh_rtc_ops = {
 	.open		= sh_rtc_open,
 	.release	= sh_rtc_release,
 	.ioctl		= sh_rtc_ioctl,
 	.read_time	= sh_rtc_read_time,
 	.set_time	= sh_rtc_set_time,
 	.proc		= sh_rtc_proc,
 };

 static int __devinit sh_rtc_probe(struct platform_device *pdev)
 {
 	struct sh_rtc *rtc;
 	struct resource *res;
 	int ret = -ENOENT;

 	rtc = kzalloc(sizeof(struct sh_rtc), GFP_KERNEL);
 	if (unlikely(!rtc))
 		return -ENOMEM;

 	spin_lock_init(&rtc->lock);

 	rtc->periodic_irq = platform_get_irq(pdev, 0);
 	if (unlikely(rtc->periodic_irq < 0)) {
 		dev_err(&pdev->dev, "No IRQ for period\n");
 		goto err_badres;
 	}

 	rtc->carry_irq = platform_get_irq(pdev, 1);
 	if (unlikely(rtc->carry_irq < 0)) {
 		dev_err(&pdev->dev, "No IRQ for carry\n");
 		goto err_badres;
 	}

 	rtc->alarm_irq = platform_get_irq(pdev, 2);
 	if (unlikely(rtc->alarm_irq < 0)) {
 		dev_err(&pdev->dev, "No IRQ for alarm\n");
 		goto err_badres;
 	}

 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
 	if (unlikely(res == NULL)) {
 		dev_err(&pdev->dev, "No IO resource\n");
 		goto err_badres;
 	}

 	rtc->regsize = res->end - res->start + 1;

 	rtc->res = request_mem_region(res->start, rtc->regsize, pdev->name);
 	if (unlikely(!rtc->res)) {
 		ret = -EBUSY;
 		goto err_badres;
 	}

 	rtc->regbase = (void __iomem *)rtc->res->start;
 	if (unlikely(!rtc->regbase)) {
 		ret = -EINVAL;
 		goto err_badmap;
 	}

 	rtc->rtc_dev = rtc_device_register("sh", &pdev->dev,
 					   &sh_rtc_ops, THIS_MODULE);
 	if (IS_ERR(rtc)) {
 		ret = PTR_ERR(rtc->rtc_dev);
 		goto err_badmap;
 	}

 	platform_set_drvdata(pdev, rtc);

 	return 0;

 err_badmap:
 	release_resource(rtc->res);
 err_badres:
 	kfree(rtc);

 	return ret;
 }

 static int __devexit sh_rtc_remove(struct platform_device *pdev)
 {
 	struct sh_rtc *rtc = platform_get_drvdata(pdev);

 	if (likely(rtc->rtc_dev))
 		rtc_device_unregister(rtc->rtc_dev);

 	sh_rtc_setpie(&pdev->dev, 0);
 	sh_rtc_setaie(&pdev->dev, 0);

 	release_resource(rtc->res);

 	platform_set_drvdata(pdev, NULL);

 	kfree(rtc);

 	return 0;
 }
 static struct platform_driver sh_rtc_platform_driver = {
 	.driver		= {
 		.name	= "sh-rtc",
 		.owner	= THIS_MODULE,
 	},
 	.probe		= sh_rtc_probe,
 	.remove		= __devexit_p(sh_rtc_remove),
 };

 static int __init sh_rtc_init(void)
 {
 	return platform_driver_register(&sh_rtc_platform_driver);
 }

 static void __exit sh_rtc_exit(void)
 {
 	platform_driver_unregister(&sh_rtc_platform_driver);
 }

 module_init(sh_rtc_init);
 module_exit(sh_rtc_exit);

 MODULE_DESCRIPTION("SuperH on-chip RTC driver");
 MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
 MODULE_LICENSE("GPL");
	/*
	* SuperH On-Chip RTC Support
	*
	* Copyright (C) 2006 Paul Mundt
	*
	* Based on the old arch/sh/kernel/cpu/rtc.c by:
	*
	* Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
	* Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
	*
	* This file is subject to the terms and conditions of the GNU General Public
	* License. See the file "COPYING" in the main directory of this archive
	* for more details.
	*/
	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/bcd.h>
	#include <linux/rtc.h>
	#include <linux/init.h>
	#include <linux/platform_device.h>
	#include <linux/seq_file.h>
	#include <linux/interrupt.h>
	#include <linux/spinlock.h>
	#include <asm/io.h>

	#ifdef CONFIG_CPU_SH3
	#define rtc_reg_size sizeof(u16)
	#define RTC_BIT_INVERTED 0 /* No bug on SH7708, SH7709A */
	#elif defined(CONFIG_CPU_SH4)
	#define rtc_reg_size sizeof(u32)
	#define RTC_BIT_INVERTED 0x40 /* bug on SH7750, SH7750S */
	#endif

	#define RTC_REG(r) ((r) * rtc_reg_size)

	#define R64CNT RTC_REG(0)
	#define RSECCNT RTC_REG(1)
	#define RMINCNT RTC_REG(2)
	#define RHRCNT RTC_REG(3)
	#define RWKCNT RTC_REG(4)
	#define RDAYCNT RTC_REG(5)
	#define RMONCNT RTC_REG(6)
	#define RYRCNT RTC_REG(7)
	#define RSECAR RTC_REG(8)
	#define RMINAR RTC_REG(9)
	#define RHRAR RTC_REG(10)
	#define RWKAR RTC_REG(11)
	#define RDAYAR RTC_REG(12)
	#define RMONAR RTC_REG(13)
	#define RCR1 RTC_REG(14)
	#define RCR2 RTC_REG(15)

	/* RCR1 Bits */
	#define RCR1_CF 0x80 /* Carry Flag */
	#define RCR1_CIE 0x10 /* Carry Interrupt Enable */
	#define RCR1_AIE 0x08 /* Alarm Interrupt Enable */
	#define RCR1_AF 0x01 /* Alarm Flag */

	/* RCR2 Bits */
	#define RCR2_PEF 0x80 /* PEriodic interrupt Flag */
	#define RCR2_PESMASK 0x70 /* Periodic interrupt Set */
	#define RCR2_RTCEN 0x08 /* ENable RTC */
	#define RCR2_ADJ 0x04 /* ADJustment (30-second) */
	#define RCR2_RESET 0x02 /* Reset bit */
	#define RCR2_START 0x01 /* Start bit */

	struct sh_rtc {
	void __iomem *regbase;
	unsigned long regsize;
	struct resource *res;
	unsigned int alarm_irq, periodic_irq, carry_irq;
	struct rtc_device *rtc_dev;
	spinlock_t lock;
	};

	static irqreturn_t sh_rtc_interrupt(int irq, void *id)
	{
	struct platform_device *pdev = id;
	struct sh_rtc *rtc = platform_get_drvdata(pdev);
	unsigned int tmp, events = 0;

	spin_lock(&rtc->lock);

	tmp = readb(rtc->regbase + RCR1);

	if (tmp & RCR1_AF)
	events \|= RTC_AF \| RTC_IRQF;

	tmp &= ~(RCR1_CF \| RCR1_AF);

	writeb(tmp, rtc->regbase + RCR1);

	rtc_update_irq(&rtc->rtc_dev->class_dev, 1, events);

	spin_unlock(&rtc->lock);

	return IRQ_HANDLED;
	}

	static irqreturn_t sh_rtc_periodic(int irq, void *id)
	{
	struct sh_rtc *rtc = dev_get_drvdata(id);

	spin_lock(&rtc->lock);

	rtc_update_irq(&rtc->rtc_dev->class_dev, 1, RTC_PF \| RTC_IRQF);

	spin_unlock(&rtc->lock);

	return IRQ_HANDLED;
	}

	static inline void sh_rtc_setpie(struct device *dev, unsigned int enable)
	{
	struct sh_rtc *rtc = dev_get_drvdata(dev);
	unsigned int tmp;

	spin_lock_irq(&rtc->lock);

	tmp = readb(rtc->regbase + RCR2);

	if (enable) {
	tmp &= ~RCR2_PESMASK;
	tmp \|= RCR2_PEF \| (2 << 4);
	} else
	tmp &= ~(RCR2_PESMASK \| RCR2_PEF);

	writeb(tmp, rtc->regbase + RCR2);

	spin_unlock_irq(&rtc->lock);
	}

	static inline void sh_rtc_setaie(struct device *dev, unsigned int enable)
	{
	struct sh_rtc *rtc = dev_get_drvdata(dev);
	unsigned int tmp;

	spin_lock_irq(&rtc->lock);

	tmp = readb(rtc->regbase + RCR1);

	if (enable)
	tmp \|= RCR1_AIE;
	else
	tmp &= ~RCR1_AIE;

	writeb(tmp, rtc->regbase + RCR1);

	spin_unlock_irq(&rtc->lock);
	}

	static int sh_rtc_open(struct device *dev)
	{
	struct sh_rtc *rtc = dev_get_drvdata(dev);
	unsigned int tmp;
	int ret;

	tmp = readb(rtc->regbase + RCR1);
	tmp &= ~RCR1_CF;
	tmp \|= RCR1_CIE;
	writeb(tmp, rtc->regbase + RCR1);

	ret = request_irq(rtc->periodic_irq, sh_rtc_periodic, IRQF_DISABLED,
	"sh-rtc period", dev);
	if (unlikely(ret)) {
	dev_err(dev, "request period IRQ failed with %d, IRQ %d\n",
	ret, rtc->periodic_irq);
	return ret;
	}

	ret = request_irq(rtc->carry_irq, sh_rtc_interrupt, IRQF_DISABLED,
	"sh-rtc carry", dev);
	if (unlikely(ret)) {
	dev_err(dev, "request carry IRQ failed with %d, IRQ %d\n",
	ret, rtc->carry_irq);
	free_irq(rtc->periodic_irq, dev);
	goto err_bad_carry;
	}

	ret = request_irq(rtc->alarm_irq, sh_rtc_interrupt, IRQF_DISABLED,
	"sh-rtc alarm", dev);
	if (unlikely(ret)) {
	dev_err(dev, "request alarm IRQ failed with %d, IRQ %d\n",
	ret, rtc->alarm_irq);
	goto err_bad_alarm;
	}

	return 0;

	err_bad_alarm:
	free_irq(rtc->carry_irq, dev);
	err_bad_carry:
	free_irq(rtc->periodic_irq, dev);

	return ret;
	}

	static void sh_rtc_release(struct device *dev)
	{
	struct sh_rtc *rtc = dev_get_drvdata(dev);

	sh_rtc_setpie(dev, 0);

	free_irq(rtc->periodic_irq, dev);
	free_irq(rtc->carry_irq, dev);
	free_irq(rtc->alarm_irq, dev);
	}

	static int sh_rtc_proc(struct device dev, struct seq_file seq)
	{
	struct sh_rtc *rtc = dev_get_drvdata(dev);
	unsigned int tmp;

	tmp = readb(rtc->regbase + RCR1);
	seq_printf(seq, "alarm_IRQ\t: %s\n",
	(tmp & RCR1_AIE) ? "yes" : "no");
	seq_printf(seq, "carry_IRQ\t: %s\n",
	(tmp & RCR1_CIE) ? "yes" : "no");

	tmp = readb(rtc->regbase + RCR2);
	seq_printf(seq, "periodic_IRQ\t: %s\n",
	(tmp & RCR2_PEF) ? "yes" : "no");

	return 0;
	}

	static int sh_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
	{
	unsigned int ret = -ENOIOCTLCMD;

	switch (cmd) {
	case RTC_PIE_OFF:
	case RTC_PIE_ON:
	sh_rtc_setpie(dev, cmd == RTC_PIE_ON);
	ret = 0;
	break;
	case RTC_AIE_OFF:
	case RTC_AIE_ON:
	sh_rtc_setaie(dev, cmd == RTC_AIE_ON);
	ret = 0;
	break;
	}

	return ret;
	}

	static int sh_rtc_read_time(struct device dev, struct rtc_time tm)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct sh_rtc *rtc = platform_get_drvdata(pdev);
	unsigned int sec128, sec2, yr, yr100, cf_bit;

	do {
	unsigned int tmp;

	spin_lock_irq(&rtc->lock);

	tmp = readb(rtc->regbase + RCR1);
	tmp &= ~RCR1_CF; /* Clear CF-bit */
	tmp \|= RCR1_CIE;
	writeb(tmp, rtc->regbase + RCR1);

	sec128 = readb(rtc->regbase + R64CNT);

	tm->tm_sec = BCD2BIN(readb(rtc->regbase + RSECCNT));
	tm->tm_min = BCD2BIN(readb(rtc->regbase + RMINCNT));
	tm->tm_hour = BCD2BIN(readb(rtc->regbase + RHRCNT));
	tm->tm_wday = BCD2BIN(readb(rtc->regbase + RWKCNT));
	tm->tm_mday = BCD2BIN(readb(rtc->regbase + RDAYCNT));
	tm->tm_mon = BCD2BIN(readb(rtc->regbase + RMONCNT));

	#if defined(CONFIG_CPU_SH4)
	yr = readw(rtc->regbase + RYRCNT);
	yr100 = BCD2BIN(yr >> 8);
	yr &= 0xff;
	#else
	yr = readb(rtc->regbase + RYRCNT);
	yr100 = BCD2BIN((yr == 0x99) ? 0x19 : 0x20);
	#endif

	tm->tm_year = (yr100 * 100 + BCD2BIN(yr)) - 1900;

	sec2 = readb(rtc->regbase + R64CNT);
	cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF;

	spin_unlock_irq(&rtc->lock);
	} while (cf_bit != 0 \|\| ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0);

	#if RTC_BIT_INVERTED != 0
	if ((sec128 & RTC_BIT_INVERTED))
	tm->tm_sec--;
	#endif

	dev_dbg(&dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
	"mday=%d, mon=%d, year=%d, wday=%d\n",
	__FUNCTION__,
	tm->tm_sec, tm->tm_min, tm->tm_hour,
	tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);

	if (rtc_valid_tm(tm) < 0)
	dev_err(dev, "invalid date\n");

	return 0;
	}

	static int sh_rtc_set_time(struct device dev, struct rtc_time tm)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct sh_rtc *rtc = platform_get_drvdata(pdev);
	unsigned int tmp;
	int year;

	spin_lock_irq(&rtc->lock);

	/* Reset pre-scaler & stop RTC */
	tmp = readb(rtc->regbase + RCR2);
	tmp \|= RCR2_RESET;
	writeb(tmp, rtc->regbase + RCR2);

	writeb(BIN2BCD(tm->tm_sec), rtc->regbase + RSECCNT);
	writeb(BIN2BCD(tm->tm_min), rtc->regbase + RMINCNT);
	writeb(BIN2BCD(tm->tm_hour), rtc->regbase + RHRCNT);
	writeb(BIN2BCD(tm->tm_wday), rtc->regbase + RWKCNT);
	writeb(BIN2BCD(tm->tm_mday), rtc->regbase + RDAYCNT);
	writeb(BIN2BCD(tm->tm_mon), rtc->regbase + RMONCNT);

	#ifdef CONFIG_CPU_SH3
	year = tm->tm_year % 100;
	writeb(BIN2BCD(year), rtc->regbase + RYRCNT);
	#else
	year = (BIN2BCD((tm->tm_year + 1900) / 100) << 8) \|
	BIN2BCD(tm->tm_year % 100);
	writew(year, rtc->regbase + RYRCNT);
	#endif

	/* Start RTC */
	tmp = readb(rtc->regbase + RCR2);
	tmp &= ~RCR2_RESET;
	tmp \|= RCR2_RTCEN \| RCR2_START;
	writeb(tmp, rtc->regbase + RCR2);

	spin_unlock_irq(&rtc->lock);

	return 0;
	}

	static struct rtc_class_ops sh_rtc_ops = {
	.open = sh_rtc_open,
	.release = sh_rtc_release,
	.ioctl = sh_rtc_ioctl,
	.read_time = sh_rtc_read_time,
	.set_time = sh_rtc_set_time,
	.proc = sh_rtc_proc,
	};

	static int __devinit sh_rtc_probe(struct platform_device *pdev)
	{
	struct sh_rtc *rtc;
	struct resource *res;
	int ret = -ENOENT;

	rtc = kzalloc(sizeof(struct sh_rtc), GFP_KERNEL);
	if (unlikely(!rtc))
	return -ENOMEM;

	spin_lock_init(&rtc->lock);

	rtc->periodic_irq = platform_get_irq(pdev, 0);
	if (unlikely(rtc->periodic_irq < 0)) {
	dev_err(&pdev->dev, "No IRQ for period\n");
	goto err_badres;
	}

	rtc->carry_irq = platform_get_irq(pdev, 1);
	if (unlikely(rtc->carry_irq < 0)) {
	dev_err(&pdev->dev, "No IRQ for carry\n");
	goto err_badres;
	}

	rtc->alarm_irq = platform_get_irq(pdev, 2);
	if (unlikely(rtc->alarm_irq < 0)) {
	dev_err(&pdev->dev, "No IRQ for alarm\n");
	goto err_badres;
	}

	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
	if (unlikely(res == NULL)) {
	dev_err(&pdev->dev, "No IO resource\n");
	goto err_badres;
	}

	rtc->regsize = res->end - res->start + 1;

	rtc->res = request_mem_region(res->start, rtc->regsize, pdev->name);
	if (unlikely(!rtc->res)) {
	ret = -EBUSY;
	goto err_badres;
	}

	rtc->regbase = (void __iomem *)rtc->res->start;
	if (unlikely(!rtc->regbase)) {
	ret = -EINVAL;
	goto err_badmap;
	}

	rtc->rtc_dev = rtc_device_register("sh", &pdev->dev,
	&sh_rtc_ops, THIS_MODULE);
	if (IS_ERR(rtc)) {
	ret = PTR_ERR(rtc->rtc_dev);
	goto err_badmap;
	}

	platform_set_drvdata(pdev, rtc);

	return 0;

	err_badmap:
	release_resource(rtc->res);
	err_badres:
	kfree(rtc);

	return ret;
	}

	static int __devexit sh_rtc_remove(struct platform_device *pdev)
	{
	struct sh_rtc *rtc = platform_get_drvdata(pdev);

	if (likely(rtc->rtc_dev))
	rtc_device_unregister(rtc->rtc_dev);

	sh_rtc_setpie(&pdev->dev, 0);
	sh_rtc_setaie(&pdev->dev, 0);

	release_resource(rtc->res);

	platform_set_drvdata(pdev, NULL);

	kfree(rtc);

	return 0;
	}
	static struct platform_driver sh_rtc_platform_driver = {
	.driver = {
	.name = "sh-rtc",
	.owner = THIS_MODULE,
	},
	.probe = sh_rtc_probe,
	.remove = __devexit_p(sh_rtc_remove),
	};

	static int __init sh_rtc_init(void)
	{
	return platform_driver_register(&sh_rtc_platform_driver);
	}

	static void __exit sh_rtc_exit(void)
	{
	platform_driver_unregister(&sh_rtc_platform_driver);
	}

	module_init(sh_rtc_init);
	module_exit(sh_rtc_exit);

	MODULE_DESCRIPTION("SuperH on-chip RTC driver");
	MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
	MODULE_LICENSE("GPL");