[net-next-2.6.git] / drivers / rtc / rtc-s3c.c

/* drivers/rtc/rtc-s3c.c
 *
 * Copyright (c) 2004,2006 Simtec Electronics
 *	Ben Dooks, <ben@simtec.co.uk>
 *	http://armlinux.simtec.co.uk/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * S3C2410/S3C2440/S3C24XX Internal RTC Driver
*/

#include <linux/module.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/rtc.h>
#include <linux/bcd.h>
#include <linux/clk.h>
#include <linux/log2.h>

#include <mach/hardware.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/plat-s3c/regs-rtc.h>

/* I have yet to find an S3C implementation with more than one
 * of these rtc blocks in */

static struct resource *s3c_rtc_mem;

static void __iomem *s3c_rtc_base;
static int s3c_rtc_alarmno = NO_IRQ;
static int s3c_rtc_tickno  = NO_IRQ;

static DEFINE_SPINLOCK(s3c_rtc_pie_lock);

/* IRQ Handlers */

static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
{
	struct rtc_device *rdev = id;

	rtc_update_irq(rdev, 1, RTC_AF | RTC_IRQF);
	return IRQ_HANDLED;
}

static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
{
	struct rtc_device *rdev = id;

	rtc_update_irq(rdev, 1, RTC_PF | RTC_IRQF);
	return IRQ_HANDLED;
}

/* Update control registers */
static void s3c_rtc_setaie(int to)
{
	unsigned int tmp;

	pr_debug("%s: aie=%d\n", __func__, to);

	tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;

	if (to)
		tmp |= S3C2410_RTCALM_ALMEN;

	writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
}

static int s3c_rtc_setpie(struct device *dev, int enabled)
{
	unsigned int tmp;

	pr_debug("%s: pie=%d\n", __func__, enabled);

	spin_lock_irq(&s3c_rtc_pie_lock);
	tmp = readb(s3c_rtc_base + S3C2410_TICNT) & ~S3C2410_TICNT_ENABLE;

	if (enabled)
		tmp |= S3C2410_TICNT_ENABLE;

	writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
	spin_unlock_irq(&s3c_rtc_pie_lock);

	return 0;
}

static int s3c_rtc_setfreq(struct device *dev, int freq)
{
	unsigned int tmp;

	spin_lock_irq(&s3c_rtc_pie_lock);

	tmp = readb(s3c_rtc_base + S3C2410_TICNT) & S3C2410_TICNT_ENABLE;
	tmp |= (128 / freq)-1;

	writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
	spin_unlock_irq(&s3c_rtc_pie_lock);

	return 0;
}

/* Time read/write */

static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
{
	unsigned int have_retried = 0;
	void __iomem *base = s3c_rtc_base;

 retry_get_time:
	rtc_tm->tm_min  = readb(base + S3C2410_RTCMIN);
	rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR);
	rtc_tm->tm_mday = readb(base + S3C2410_RTCDATE);
	rtc_tm->tm_mon  = readb(base + S3C2410_RTCMON);
	rtc_tm->tm_year = readb(base + S3C2410_RTCYEAR);
	rtc_tm->tm_sec  = readb(base + S3C2410_RTCSEC);

	/* the only way to work out wether the system was mid-update
	 * when we read it is to check the second counter, and if it
	 * is zero, then we re-try the entire read
	 */

	if (rtc_tm->tm_sec == 0 && !have_retried) {
		have_retried = 1;
		goto retry_get_time;
	}

	pr_debug("read time %02x.%02x.%02x %02x/%02x/%02x\n",
		 rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
		 rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);

	BCD_TO_BIN(rtc_tm->tm_sec);
	BCD_TO_BIN(rtc_tm->tm_min);
	BCD_TO_BIN(rtc_tm->tm_hour);
	BCD_TO_BIN(rtc_tm->tm_mday);
	BCD_TO_BIN(rtc_tm->tm_mon);
	BCD_TO_BIN(rtc_tm->tm_year);

	rtc_tm->tm_year += 100;
	rtc_tm->tm_mon -= 1;

	return 0;
}

static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
{
	void __iomem *base = s3c_rtc_base;
	int year = tm->tm_year - 100;

	pr_debug("set time %02d.%02d.%02d %02d/%02d/%02d\n",
		 tm->tm_year, tm->tm_mon, tm->tm_mday,
		 tm->tm_hour, tm->tm_min, tm->tm_sec);

	/* we get around y2k by simply not supporting it */

	if (year < 0 || year >= 100) {
		dev_err(dev, "rtc only supports 100 years\n");
		return -EINVAL;
	}

	writeb(BIN2BCD(tm->tm_sec),  base + S3C2410_RTCSEC);
	writeb(BIN2BCD(tm->tm_min),  base + S3C2410_RTCMIN);
	writeb(BIN2BCD(tm->tm_hour), base + S3C2410_RTCHOUR);
	writeb(BIN2BCD(tm->tm_mday), base + S3C2410_RTCDATE);
	writeb(BIN2BCD(tm->tm_mon + 1), base + S3C2410_RTCMON);
	writeb(BIN2BCD(year), base + S3C2410_RTCYEAR);

	return 0;
}

static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct rtc_time *alm_tm = &alrm->time;
	void __iomem *base = s3c_rtc_base;
	unsigned int alm_en;

	alm_tm->tm_sec  = readb(base + S3C2410_ALMSEC);
	alm_tm->tm_min  = readb(base + S3C2410_ALMMIN);
	alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR);
	alm_tm->tm_mon  = readb(base + S3C2410_ALMMON);
	alm_tm->tm_mday = readb(base + S3C2410_ALMDATE);
	alm_tm->tm_year = readb(base + S3C2410_ALMYEAR);

	alm_en = readb(base + S3C2410_RTCALM);

	alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;

	pr_debug("read alarm %02x %02x.%02x.%02x %02x/%02x/%02x\n",
		 alm_en,
		 alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
		 alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);


	/* decode the alarm enable field */

	if (alm_en & S3C2410_RTCALM_SECEN)
		BCD_TO_BIN(alm_tm->tm_sec);
	else
		alm_tm->tm_sec = 0xff;

	if (alm_en & S3C2410_RTCALM_MINEN)
		BCD_TO_BIN(alm_tm->tm_min);
	else
		alm_tm->tm_min = 0xff;

	if (alm_en & S3C2410_RTCALM_HOUREN)
		BCD_TO_BIN(alm_tm->tm_hour);
	else
		alm_tm->tm_hour = 0xff;

	if (alm_en & S3C2410_RTCALM_DAYEN)
		BCD_TO_BIN(alm_tm->tm_mday);
	else
		alm_tm->tm_mday = 0xff;

	if (alm_en & S3C2410_RTCALM_MONEN) {
		BCD_TO_BIN(alm_tm->tm_mon);
		alm_tm->tm_mon -= 1;
	} else {
		alm_tm->tm_mon = 0xff;
	}

	if (alm_en & S3C2410_RTCALM_YEAREN)
		BCD_TO_BIN(alm_tm->tm_year);
	else
		alm_tm->tm_year = 0xffff;

	return 0;
}

static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct rtc_time *tm = &alrm->time;
	void __iomem *base = s3c_rtc_base;
	unsigned int alrm_en;

	pr_debug("s3c_rtc_setalarm: %d, %02x/%02x/%02x %02x.%02x.%02x\n",
		 alrm->enabled,
		 tm->tm_mday & 0xff, tm->tm_mon & 0xff, tm->tm_year & 0xff,
		 tm->tm_hour & 0xff, tm->tm_min & 0xff, tm->tm_sec);


	alrm_en = readb(base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
	writeb(0x00, base + S3C2410_RTCALM);

	if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
		alrm_en |= S3C2410_RTCALM_SECEN;
		writeb(BIN2BCD(tm->tm_sec), base + S3C2410_ALMSEC);
	}

	if (tm->tm_min < 60 && tm->tm_min >= 0) {
		alrm_en |= S3C2410_RTCALM_MINEN;
		writeb(BIN2BCD(tm->tm_min), base + S3C2410_ALMMIN);
	}

	if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
		alrm_en |= S3C2410_RTCALM_HOUREN;
		writeb(BIN2BCD(tm->tm_hour), base + S3C2410_ALMHOUR);
	}

	pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en);

	writeb(alrm_en, base + S3C2410_RTCALM);

	s3c_rtc_setaie(alrm->enabled);

	if (alrm->enabled)
		enable_irq_wake(s3c_rtc_alarmno);
	else
		disable_irq_wake(s3c_rtc_alarmno);

	return 0;
}

static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
{
	unsigned int ticnt = readb(s3c_rtc_base + S3C2410_TICNT);

	seq_printf(seq, "periodic_IRQ\t: %s\n",
		     (ticnt & S3C2410_TICNT_ENABLE) ? "yes" : "no" );
	return 0;
}

static int s3c_rtc_open(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
	int ret;

	ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq,
			  IRQF_DISABLED,  "s3c2410-rtc alarm", rtc_dev);

	if (ret) {
		dev_err(dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret);
		return ret;
	}

	ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq,
			  IRQF_DISABLED,  "s3c2410-rtc tick", rtc_dev);

	if (ret) {
		dev_err(dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret);
		goto tick_err;
	}

	return ret;

 tick_err:
	free_irq(s3c_rtc_alarmno, rtc_dev);
	return ret;
}

static void s3c_rtc_release(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct rtc_device *rtc_dev = platform_get_drvdata(pdev);

	/* do not clear AIE here, it may be needed for wake */

	s3c_rtc_setpie(dev, 0);
	free_irq(s3c_rtc_alarmno, rtc_dev);
	free_irq(s3c_rtc_tickno, rtc_dev);
}

static const struct rtc_class_ops s3c_rtcops = {
	.open		= s3c_rtc_open,
	.release	= s3c_rtc_release,
	.read_time	= s3c_rtc_gettime,
	.set_time	= s3c_rtc_settime,
	.read_alarm	= s3c_rtc_getalarm,
	.set_alarm	= s3c_rtc_setalarm,
	.irq_set_freq	= s3c_rtc_setfreq,
	.irq_set_state	= s3c_rtc_setpie,
	.proc	        = s3c_rtc_proc,
};

static void s3c_rtc_enable(struct platform_device *pdev, int en)
{
	void __iomem *base = s3c_rtc_base;
	unsigned int tmp;

	if (s3c_rtc_base == NULL)
		return;

	if (!en) {
		tmp = readb(base + S3C2410_RTCCON);
		writeb(tmp & ~S3C2410_RTCCON_RTCEN, base + S3C2410_RTCCON);

		tmp = readb(base + S3C2410_TICNT);
		writeb(tmp & ~S3C2410_TICNT_ENABLE, base + S3C2410_TICNT);
	} else {
		/* re-enable the device, and check it is ok */

		if ((readb(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0){
			dev_info(&pdev->dev, "rtc disabled, re-enabling\n");

			tmp = readb(base + S3C2410_RTCCON);
			writeb(tmp|S3C2410_RTCCON_RTCEN, base+S3C2410_RTCCON);
		}

		if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)){
			dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n");

			tmp = readb(base + S3C2410_RTCCON);
			writeb(tmp& ~S3C2410_RTCCON_CNTSEL, base+S3C2410_RTCCON);
		}

		if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)){
			dev_info(&pdev->dev, "removing RTCCON_CLKRST\n");

			tmp = readb(base + S3C2410_RTCCON);
			writeb(tmp & ~S3C2410_RTCCON_CLKRST, base+S3C2410_RTCCON);
		}
	}
}

static int __devexit s3c_rtc_remove(struct platform_device *dev)
{
	struct rtc_device *rtc = platform_get_drvdata(dev);

	platform_set_drvdata(dev, NULL);
	rtc_device_unregister(rtc);

	s3c_rtc_setpie(&dev->dev, 0);
	s3c_rtc_setaie(0);

	iounmap(s3c_rtc_base);
	release_resource(s3c_rtc_mem);
	kfree(s3c_rtc_mem);

	return 0;
}

static int __devinit s3c_rtc_probe(struct platform_device *pdev)
{
	struct rtc_device *rtc;
	struct resource *res;
	int ret;

	pr_debug("%s: probe=%p\n", __func__, pdev);

	/* find the IRQs */

	s3c_rtc_tickno = platform_get_irq(pdev, 1);
	if (s3c_rtc_tickno < 0) {
		dev_err(&pdev->dev, "no irq for rtc tick\n");
		return -ENOENT;
	}

	s3c_rtc_alarmno = platform_get_irq(pdev, 0);
	if (s3c_rtc_alarmno < 0) {
		dev_err(&pdev->dev, "no irq for alarm\n");
		return -ENOENT;
	}

	pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
		 s3c_rtc_tickno, s3c_rtc_alarmno);

	/* get the memory region */

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (res == NULL) {
		dev_err(&pdev->dev, "failed to get memory region resource\n");
		return -ENOENT;
	}

	s3c_rtc_mem = request_mem_region(res->start,
					 res->end-res->start+1,
					 pdev->name);

	if (s3c_rtc_mem == NULL) {
		dev_err(&pdev->dev, "failed to reserve memory region\n");
		ret = -ENOENT;
		goto err_nores;
	}

	s3c_rtc_base = ioremap(res->start, res->end - res->start + 1);
	if (s3c_rtc_base == NULL) {
		dev_err(&pdev->dev, "failed ioremap()\n");
		ret = -EINVAL;
		goto err_nomap;
	}

	/* check to see if everything is setup correctly */

	s3c_rtc_enable(pdev, 1);

 	pr_debug("s3c2410_rtc: RTCCON=%02x\n",
		 readb(s3c_rtc_base + S3C2410_RTCCON));

	s3c_rtc_setfreq(&pdev->dev, 1);

	/* register RTC and exit */

	rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops,
				  THIS_MODULE);

	if (IS_ERR(rtc)) {
		dev_err(&pdev->dev, "cannot attach rtc\n");
		ret = PTR_ERR(rtc);
		goto err_nortc;
	}

	rtc->max_user_freq = 128;

	platform_set_drvdata(pdev, rtc);
	return 0;

 err_nortc:
	s3c_rtc_enable(pdev, 0);
	iounmap(s3c_rtc_base);

 err_nomap:
	release_resource(s3c_rtc_mem);

 err_nores:
	return ret;
}

#ifdef CONFIG_PM

/* RTC Power management control */

static int ticnt_save;

static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
{
	/* save TICNT for anyone using periodic interrupts */
	ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
	s3c_rtc_enable(pdev, 0);
	return 0;
}

static int s3c_rtc_resume(struct platform_device *pdev)
{
	s3c_rtc_enable(pdev, 1);
	writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
	return 0;
}
#else
#define s3c_rtc_suspend NULL
#define s3c_rtc_resume  NULL
#endif

static struct platform_driver s3c2410_rtcdrv = {
	.probe		= s3c_rtc_probe,
	.remove		= __devexit_p(s3c_rtc_remove),
	.suspend	= s3c_rtc_suspend,
	.resume		= s3c_rtc_resume,
	.driver		= {
		.name	= "s3c2410-rtc",
		.owner	= THIS_MODULE,
	},
};

static char __initdata banner[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";

static int __init s3c_rtc_init(void)
{
	printk(banner);
	return platform_driver_register(&s3c2410_rtcdrv);
}

static void __exit s3c_rtc_exit(void)
{
	platform_driver_unregister(&s3c2410_rtcdrv);
}

module_init(s3c_rtc_init);
module_exit(s3c_rtc_exit);

MODULE_DESCRIPTION("Samsung S3C RTC Driver");
MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:s3c2410-rtc");
Commit	Line	Data
1add6781 BD	1	/* drivers/rtc/rtc-s3c.c
	2	*
	3	* Copyright (c) 2004,2006 Simtec Electronics
	4	* Ben Dooks, <ben@simtec.co.uk>
	5	* http://armlinux.simtec.co.uk/
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*
	11	* S3C2410/S3C2440/S3C24XX Internal RTC Driver
	12	*/
	13
	14	#include <linux/module.h>
	15	#include <linux/fs.h>
	16	#include <linux/string.h>
	17	#include <linux/init.h>
	18	#include <linux/platform_device.h>
	19	#include <linux/interrupt.h>
	20	#include <linux/rtc.h>
	21	#include <linux/bcd.h>
	22	#include <linux/clk.h>
9974b6ea	23	#include <linux/log2.h>
1add6781	24
a09e64fb	25	#include <mach/hardware.h>
1add6781 BD	26	#include <asm/uaccess.h>
	27	#include <asm/io.h>
	28	#include <asm/irq.h>
252e4838	29	#include <asm/plat-s3c/regs-rtc.h>
1add6781 BD	30
	31	/* I have yet to find an S3C implementation with more than one
	32	* of these rtc blocks in */
	33
	34	static struct resource *s3c_rtc_mem;
	35
	36	static void __iomem *s3c_rtc_base;
	37	static int s3c_rtc_alarmno = NO_IRQ;
	38	static int s3c_rtc_tickno = NO_IRQ;
1add6781 BD	39
1add6781 BD	40	static DEFINE_SPINLOCK(s3c_rtc_pie_lock);
1add6781 BD	41
	42	/* IRQ Handlers */
	43
7d12e780	44	static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
1add6781 BD	45	{
	46	struct rtc_device *rdev = id;
	47
ab6a2d70	48	rtc_update_irq(rdev, 1, RTC_AF \| RTC_IRQF);
1add6781 BD	49	return IRQ_HANDLED;
	50	}
	51
7d12e780	52	static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
1add6781 BD	53	{
	54	struct rtc_device *rdev = id;
	55
773be7ee	56	rtc_update_irq(rdev, 1, RTC_PF \| RTC_IRQF);
1add6781 BD	57	return IRQ_HANDLED;
	58	}
	59
	60	/* Update control registers */
	61	static void s3c_rtc_setaie(int to)
	62	{
	63	unsigned int tmp;
	64
2a4e2b87	65	pr_debug("%s: aie=%d\n", __func__, to);
1add6781	66
9a654518	67	tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
1add6781 BD	68
	69	if (to)
	70	tmp \|= S3C2410_RTCALM_ALMEN;
	71
9a654518	72	writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
1add6781 BD	73	}
1add6781 BD	74
773be7ee	75	static int s3c_rtc_setpie(struct device *dev, int enabled)
1add6781 BD	76	{
	77	unsigned int tmp;
	78
773be7ee	79	pr_debug("%s: pie=%d\n", __func__, enabled);
1add6781 BD	80
1add6781 BD	81	spin_lock_irq(&s3c_rtc_pie_lock);
9a654518	82	tmp = readb(s3c_rtc_base + S3C2410_TICNT) & ~S3C2410_TICNT_ENABLE;
1add6781	83
773be7ee	84	if (enabled)
1add6781 BD	85	tmp \|= S3C2410_TICNT_ENABLE;
1add6781 BD	86
9a654518	87	writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
1add6781	88	spin_unlock_irq(&s3c_rtc_pie_lock);
773be7ee BD	89
773be7ee BD	90	return 0;
1add6781 BD	91	}
1add6781 BD	92
773be7ee	93	static int s3c_rtc_setfreq(struct device *dev, int freq)
1add6781 BD	94	{
	95	unsigned int tmp;
	96
	97	spin_lock_irq(&s3c_rtc_pie_lock);
1add6781	98
773be7ee	99	tmp = readb(s3c_rtc_base + S3C2410_TICNT) & S3C2410_TICNT_ENABLE;
1add6781 BD	100	tmp \|= (128 / freq)-1;
1add6781 BD	101
9a654518	102	writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
1add6781	103	spin_unlock_irq(&s3c_rtc_pie_lock);
773be7ee BD	104
773be7ee BD	105	return 0;
1add6781 BD	106	}
	107
	108	/* Time read/write */
	109
	110	static int s3c_rtc_gettime(struct device dev, struct rtc_time rtc_tm)
	111	{
	112	unsigned int have_retried = 0;
9a654518	113	void __iomem *base = s3c_rtc_base;
1add6781 BD	114
1add6781 BD	115	retry_get_time:
9a654518 BD	116	rtc_tm->tm_min = readb(base + S3C2410_RTCMIN);
	117	rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR);
	118	rtc_tm->tm_mday = readb(base + S3C2410_RTCDATE);
	119	rtc_tm->tm_mon = readb(base + S3C2410_RTCMON);
	120	rtc_tm->tm_year = readb(base + S3C2410_RTCYEAR);
	121	rtc_tm->tm_sec = readb(base + S3C2410_RTCSEC);
1add6781 BD	122
	123	/* the only way to work out wether the system was mid-update
	124	* when we read it is to check the second counter, and if it
	125	* is zero, then we re-try the entire read
	126	*/
	127
	128	if (rtc_tm->tm_sec == 0 && !have_retried) {
	129	have_retried = 1;
	130	goto retry_get_time;
	131	}
	132
	133	pr_debug("read time %02x.%02x.%02x %02x/%02x/%02x\n",
	134	rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
	135	rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
	136
	137	BCD_TO_BIN(rtc_tm->tm_sec);
	138	BCD_TO_BIN(rtc_tm->tm_min);
	139	BCD_TO_BIN(rtc_tm->tm_hour);
	140	BCD_TO_BIN(rtc_tm->tm_mday);
	141	BCD_TO_BIN(rtc_tm->tm_mon);
	142	BCD_TO_BIN(rtc_tm->tm_year);
	143
	144	rtc_tm->tm_year += 100;
	145	rtc_tm->tm_mon -= 1;
	146
	147	return 0;
	148	}
	149
	150	static int s3c_rtc_settime(struct device dev, struct rtc_time tm)
	151	{
9a654518	152	void __iomem *base = s3c_rtc_base;
641741e0	153	int year = tm->tm_year - 100;
9a654518	154
641741e0 BD	155	pr_debug("set time %02d.%02d.%02d %02d/%02d/%02d\n",
	156	tm->tm_year, tm->tm_mon, tm->tm_mday,
	157	tm->tm_hour, tm->tm_min, tm->tm_sec);
	158
	159	/* we get around y2k by simply not supporting it */
1add6781	160
641741e0	161	if (year < 0 \|\| year >= 100) {
9a654518	162	dev_err(dev, "rtc only supports 100 years\n");
1add6781	163	return -EINVAL;
9a654518 BD	164	}
9a654518 BD	165
9a654518 BD	166	writeb(BIN2BCD(tm->tm_sec), base + S3C2410_RTCSEC);
	167	writeb(BIN2BCD(tm->tm_min), base + S3C2410_RTCMIN);
	168	writeb(BIN2BCD(tm->tm_hour), base + S3C2410_RTCHOUR);
	169	writeb(BIN2BCD(tm->tm_mday), base + S3C2410_RTCDATE);
	170	writeb(BIN2BCD(tm->tm_mon + 1), base + S3C2410_RTCMON);
641741e0	171	writeb(BIN2BCD(year), base + S3C2410_RTCYEAR);
1add6781 BD	172
	173	return 0;
	174	}
	175
	176	static int s3c_rtc_getalarm(struct device dev, struct rtc_wkalrm alrm)
	177	{
	178	struct rtc_time *alm_tm = &alrm->time;
9a654518	179	void __iomem *base = s3c_rtc_base;
1add6781 BD	180	unsigned int alm_en;
1add6781 BD	181
9a654518 BD	182	alm_tm->tm_sec = readb(base + S3C2410_ALMSEC);
	183	alm_tm->tm_min = readb(base + S3C2410_ALMMIN);
	184	alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR);
	185	alm_tm->tm_mon = readb(base + S3C2410_ALMMON);
	186	alm_tm->tm_mday = readb(base + S3C2410_ALMDATE);
	187	alm_tm->tm_year = readb(base + S3C2410_ALMYEAR);
1add6781	188
9a654518	189	alm_en = readb(base + S3C2410_RTCALM);
1add6781	190
a2db8dfc DB	191	alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
a2db8dfc DB	192
1add6781 BD	193	pr_debug("read alarm %02x %02x.%02x.%02x %02x/%02x/%02x\n",
	194	alm_en,
	195	alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
	196	alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
	197
	198
	199	/* decode the alarm enable field */
	200
	201	if (alm_en & S3C2410_RTCALM_SECEN)
	202	BCD_TO_BIN(alm_tm->tm_sec);
	203	else
	204	alm_tm->tm_sec = 0xff;
	205
	206	if (alm_en & S3C2410_RTCALM_MINEN)
	207	BCD_TO_BIN(alm_tm->tm_min);
	208	else
	209	alm_tm->tm_min = 0xff;
	210
	211	if (alm_en & S3C2410_RTCALM_HOUREN)
	212	BCD_TO_BIN(alm_tm->tm_hour);
	213	else
	214	alm_tm->tm_hour = 0xff;
	215
	216	if (alm_en & S3C2410_RTCALM_DAYEN)
	217	BCD_TO_BIN(alm_tm->tm_mday);
	218	else
	219	alm_tm->tm_mday = 0xff;
	220
	221	if (alm_en & S3C2410_RTCALM_MONEN) {
	222	BCD_TO_BIN(alm_tm->tm_mon);
	223	alm_tm->tm_mon -= 1;
	224	} else {
	225	alm_tm->tm_mon = 0xff;
	226	}
	227
	228	if (alm_en & S3C2410_RTCALM_YEAREN)
	229	BCD_TO_BIN(alm_tm->tm_year);
	230	else
	231	alm_tm->tm_year = 0xffff;
	232
	233	return 0;
	234	}
	235
	236	static int s3c_rtc_setalarm(struct device dev, struct rtc_wkalrm alrm)
	237	{
	238	struct rtc_time *tm = &alrm->time;
9a654518	239	void __iomem *base = s3c_rtc_base;
1add6781 BD	240	unsigned int alrm_en;
	241
	242	pr_debug("s3c_rtc_setalarm: %d, %02x/%02x/%02x %02x.%02x.%02x\n",
	243	alrm->enabled,
	244	tm->tm_mday & 0xff, tm->tm_mon & 0xff, tm->tm_year & 0xff,
	245	tm->tm_hour & 0xff, tm->tm_min & 0xff, tm->tm_sec);
	246
	247
9a654518 BD	248	alrm_en = readb(base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
9a654518 BD	249	writeb(0x00, base + S3C2410_RTCALM);
1add6781 BD	250
	251	if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
	252	alrm_en \|= S3C2410_RTCALM_SECEN;
9a654518	253	writeb(BIN2BCD(tm->tm_sec), base + S3C2410_ALMSEC);
1add6781 BD	254	}
	255
	256	if (tm->tm_min < 60 && tm->tm_min >= 0) {
	257	alrm_en \|= S3C2410_RTCALM_MINEN;
9a654518	258	writeb(BIN2BCD(tm->tm_min), base + S3C2410_ALMMIN);
1add6781 BD	259	}
	260
	261	if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
	262	alrm_en \|= S3C2410_RTCALM_HOUREN;
9a654518	263	writeb(BIN2BCD(tm->tm_hour), base + S3C2410_ALMHOUR);
1add6781 BD	264	}
	265
	266	pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en);
	267
9a654518	268	writeb(alrm_en, base + S3C2410_RTCALM);
1add6781	269
773be7ee	270	s3c_rtc_setaie(alrm->enabled);
1add6781 BD	271
	272	if (alrm->enabled)
	273	enable_irq_wake(s3c_rtc_alarmno);
	274	else
	275	disable_irq_wake(s3c_rtc_alarmno);
	276
	277	return 0;
	278	}
	279
1add6781 BD	280	static int s3c_rtc_proc(struct device dev, struct seq_file seq)
1add6781 BD	281	{
9a654518	282	unsigned int ticnt = readb(s3c_rtc_base + S3C2410_TICNT);
1add6781	283
1add6781 BD	284	seq_printf(seq, "periodic_IRQ\t: %s\n",
1add6781 BD	285	(ticnt & S3C2410_TICNT_ENABLE) ? "yes" : "no" );
1add6781 BD	286	return 0;
	287	}
	288
	289	static int s3c_rtc_open(struct device *dev)
	290	{
	291	struct platform_device *pdev = to_platform_device(dev);
	292	struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
	293	int ret;
	294
	295	ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq,
38515e90	296	IRQF_DISABLED, "s3c2410-rtc alarm", rtc_dev);
1add6781 BD	297
	298	if (ret) {
	299	dev_err(dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret);
	300	return ret;
	301	}
	302
	303	ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq,
38515e90	304	IRQF_DISABLED, "s3c2410-rtc tick", rtc_dev);
1add6781 BD	305
	306	if (ret) {
	307	dev_err(dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret);
	308	goto tick_err;
	309	}
	310
	311	return ret;
	312
	313	tick_err:
	314	free_irq(s3c_rtc_alarmno, rtc_dev);
	315	return ret;
	316	}
	317
	318	static void s3c_rtc_release(struct device *dev)
	319	{
	320	struct platform_device *pdev = to_platform_device(dev);
	321	struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
	322
	323	/* do not clear AIE here, it may be needed for wake */
	324
773be7ee	325	s3c_rtc_setpie(dev, 0);
1add6781 BD	326	free_irq(s3c_rtc_alarmno, rtc_dev);
	327	free_irq(s3c_rtc_tickno, rtc_dev);
	328	}
	329
ff8371ac	330	static const struct rtc_class_ops s3c_rtcops = {
1add6781 BD	331	.open = s3c_rtc_open,
1add6781 BD	332	.release = s3c_rtc_release,
1add6781 BD	333	.read_time = s3c_rtc_gettime,
	334	.set_time = s3c_rtc_settime,
	335	.read_alarm = s3c_rtc_getalarm,
	336	.set_alarm = s3c_rtc_setalarm,
773be7ee BD	337	.irq_set_freq = s3c_rtc_setfreq,
773be7ee BD	338	.irq_set_state = s3c_rtc_setpie,
1add6781 BD	339	.proc = s3c_rtc_proc,
	340	};
	341
	342	static void s3c_rtc_enable(struct platform_device *pdev, int en)
	343	{
9a654518	344	void __iomem *base = s3c_rtc_base;
1add6781 BD	345	unsigned int tmp;
	346
	347	if (s3c_rtc_base == NULL)
	348	return;
	349
	350	if (!en) {
9a654518 BD	351	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	352	writeb(tmp & ~S3C2410_RTCCON_RTCEN, base + S3C2410_RTCCON);
1add6781	353
9a654518 BD	354	tmp = readb(base + S3C2410_TICNT);
9a654518 BD	355	writeb(tmp & ~S3C2410_TICNT_ENABLE, base + S3C2410_TICNT);
1add6781 BD	356	} else {
	357	/* re-enable the device, and check it is ok */
	358
9a654518	359	if ((readb(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0){
1add6781 BD	360	dev_info(&pdev->dev, "rtc disabled, re-enabling\n");
1add6781 BD	361
9a654518 BD	362	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	363	writeb(tmp\|S3C2410_RTCCON_RTCEN, base+S3C2410_RTCCON);
1add6781 BD	364	}
1add6781 BD	365
9a654518	366	if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)){
1add6781 BD	367	dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n");
1add6781 BD	368
9a654518 BD	369	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	370	writeb(tmp& ~S3C2410_RTCCON_CNTSEL, base+S3C2410_RTCCON);
1add6781 BD	371	}
1add6781 BD	372
9a654518	373	if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)){
1add6781 BD	374	dev_info(&pdev->dev, "removing RTCCON_CLKRST\n");
1add6781 BD	375
9a654518 BD	376	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	377	writeb(tmp & ~S3C2410_RTCCON_CLKRST, base+S3C2410_RTCCON);
1add6781 BD	378	}
	379	}
	380	}
	381
4cd0c5c4	382	static int __devexit s3c_rtc_remove(struct platform_device *dev)
1add6781 BD	383	{
	384	struct rtc_device *rtc = platform_get_drvdata(dev);
	385
	386	platform_set_drvdata(dev, NULL);
	387	rtc_device_unregister(rtc);
	388
773be7ee	389	s3c_rtc_setpie(&dev->dev, 0);
1add6781 BD	390	s3c_rtc_setaie(0);
	391
	392	iounmap(s3c_rtc_base);
	393	release_resource(s3c_rtc_mem);
	394	kfree(s3c_rtc_mem);
	395
	396	return 0;
	397	}
	398
4cd0c5c4	399	static int __devinit s3c_rtc_probe(struct platform_device *pdev)
1add6781 BD	400	{
	401	struct rtc_device *rtc;
	402	struct resource *res;
	403	int ret;
	404
2a4e2b87	405	pr_debug("%s: probe=%p\n", __func__, pdev);
1add6781 BD	406
	407	/* find the IRQs */
	408
	409	s3c_rtc_tickno = platform_get_irq(pdev, 1);
	410	if (s3c_rtc_tickno < 0) {
	411	dev_err(&pdev->dev, "no irq for rtc tick\n");
	412	return -ENOENT;
	413	}
	414
	415	s3c_rtc_alarmno = platform_get_irq(pdev, 0);
	416	if (s3c_rtc_alarmno < 0) {
	417	dev_err(&pdev->dev, "no irq for alarm\n");
	418	return -ENOENT;
	419	}
	420
	421	pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
	422	s3c_rtc_tickno, s3c_rtc_alarmno);
	423
	424	/* get the memory region */
	425
	426	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	427	if (res == NULL) {
	428	dev_err(&pdev->dev, "failed to get memory region resource\n");
	429	return -ENOENT;
	430	}
	431
	432	s3c_rtc_mem = request_mem_region(res->start,
9a654518 BD	433	res->end-res->start+1,
9a654518 BD	434	pdev->name);
1add6781 BD	435
	436	if (s3c_rtc_mem == NULL) {
	437	dev_err(&pdev->dev, "failed to reserve memory region\n");
	438	ret = -ENOENT;
	439	goto err_nores;
	440	}
	441
	442	s3c_rtc_base = ioremap(res->start, res->end - res->start + 1);
	443	if (s3c_rtc_base == NULL) {
	444	dev_err(&pdev->dev, "failed ioremap()\n");
	445	ret = -EINVAL;
	446	goto err_nomap;
	447	}
	448
	449	/* check to see if everything is setup correctly */
	450
	451	s3c_rtc_enable(pdev, 1);
	452
9a654518 BD	453	pr_debug("s3c2410_rtc: RTCCON=%02x\n",
9a654518 BD	454	readb(s3c_rtc_base + S3C2410_RTCCON));
1add6781	455
773be7ee	456	s3c_rtc_setfreq(&pdev->dev, 1);
1add6781 BD	457
	458	/* register RTC and exit */
	459
	460	rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops,
	461	THIS_MODULE);
	462
	463	if (IS_ERR(rtc)) {
	464	dev_err(&pdev->dev, "cannot attach rtc\n");
	465	ret = PTR_ERR(rtc);
	466	goto err_nortc;
	467	}
	468
	469	rtc->max_user_freq = 128;
	470
	471	platform_set_drvdata(pdev, rtc);
	472	return 0;
	473
	474	err_nortc:
	475	s3c_rtc_enable(pdev, 0);
	476	iounmap(s3c_rtc_base);
	477
	478	err_nomap:
	479	release_resource(s3c_rtc_mem);
	480
	481	err_nores:
	482	return ret;
	483	}
	484
	485	#ifdef CONFIG_PM
	486
	487	/* RTC Power management control */
	488
1add6781 BD	489	static int ticnt_save;
	490
	491	static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
	492	{
1add6781	493	/* save TICNT for anyone using periodic interrupts */
9a654518	494	ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
1add6781	495	s3c_rtc_enable(pdev, 0);
1add6781 BD	496	return 0;
	497	}
	498
	499	static int s3c_rtc_resume(struct platform_device *pdev)
	500	{
1add6781	501	s3c_rtc_enable(pdev, 1);
9a654518	502	writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
1add6781 BD	503	return 0;
	504	}
	505	#else
	506	#define s3c_rtc_suspend NULL
	507	#define s3c_rtc_resume NULL
	508	#endif
	509
	510	static struct platform_driver s3c2410_rtcdrv = {
	511	.probe = s3c_rtc_probe,
4cd0c5c4	512	.remove = __devexit_p(s3c_rtc_remove),
1add6781 BD	513	.suspend = s3c_rtc_suspend,
	514	.resume = s3c_rtc_resume,
	515	.driver = {
	516	.name = "s3c2410-rtc",
	517	.owner = THIS_MODULE,
	518	},
	519	};
	520
	521	static char __initdata banner[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";
	522
	523	static int __init s3c_rtc_init(void)
	524	{
	525	printk(banner);
	526	return platform_driver_register(&s3c2410_rtcdrv);
	527	}
	528
	529	static void __exit s3c_rtc_exit(void)
	530	{
	531	platform_driver_unregister(&s3c2410_rtcdrv);
	532	}
	533
	534	module_init(s3c_rtc_init);
	535	module_exit(s3c_rtc_exit);
	536
	537	MODULE_DESCRIPTION("Samsung S3C RTC Driver");
	538	MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
	539	MODULE_LICENSE("GPL");
ad28a07b	540	MODULE_ALIAS("platform:s3c2410-rtc");