[deliverable/linux.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 <asm/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 int s3c_rtc_freq    = 1;

static DEFINE_SPINLOCK(s3c_rtc_pie_lock);
static unsigned int tick_count;

/* 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, tick_count++, 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 void s3c_rtc_setpie(int to)
{
	unsigned int tmp;

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

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

	if (to)
		tmp |= S3C2410_TICNT_ENABLE;

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

static void s3c_rtc_setfreq(int freq)
{
	unsigned int tmp;

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

	s3c_rtc_freq = freq;

	tmp |= (128 / freq)-1;

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

/* 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);

	if (0) {
		alrm_en = readb(base + S3C2410_RTCALM);
		alrm_en &= ~S3C2410_RTCALM_ALMEN;
		writeb(alrm_en, base + S3C2410_RTCALM);
		disable_irq_wake(s3c_rtc_alarmno);
	}

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

	return 0;
}

static int s3c_rtc_ioctl(struct device *dev,
			 unsigned int cmd, unsigned long arg)
{
	unsigned int ret = -ENOIOCTLCMD;

	switch (cmd) {
	case RTC_AIE_OFF:
	case RTC_AIE_ON:
		s3c_rtc_setaie((cmd == RTC_AIE_ON) ? 1 : 0);
		ret = 0;
		break;

	case RTC_PIE_OFF:
	case RTC_PIE_ON:
		tick_count = 0;
		s3c_rtc_setpie((cmd == RTC_PIE_ON) ? 1 : 0);
		ret = 0;
		break;

	case RTC_IRQP_READ:
		ret = put_user(s3c_rtc_freq, (unsigned long __user *)arg);
		break;

	case RTC_IRQP_SET:
		if (!is_power_of_2(arg)) {
			ret = -EINVAL;
			goto exit;
		}

		pr_debug("s3c2410_rtc: setting frequency %ld\n", arg);

		s3c_rtc_setfreq(arg);
		ret = 0;
		break;

	case RTC_UIE_ON:
	case RTC_UIE_OFF:
		ret = -EINVAL;
	}

 exit:
	return ret;
}

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" );

	seq_printf(seq, "periodic_freq\t: %d\n", s3c_rtc_freq);

	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(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,
	.ioctl		= s3c_rtc_ioctl,
	.read_time	= s3c_rtc_gettime,
	.set_time	= s3c_rtc_settime,
	.read_alarm	= s3c_rtc_getalarm,
	.set_alarm	= s3c_rtc_setalarm,
	.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(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(s3c_rtc_freq);

	/* 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 BD	24
	25	#include <asm/hardware.h>
	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;
	39	static int s3c_rtc_freq = 1;
	40
	41	static DEFINE_SPINLOCK(s3c_rtc_pie_lock);
	42	static unsigned int tick_count;
	43
	44	/* IRQ Handlers */
	45
7d12e780	46	static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
1add6781 BD	47	{
	48	struct rtc_device *rdev = id;
	49
ab6a2d70	50	rtc_update_irq(rdev, 1, RTC_AF \| RTC_IRQF);
1add6781 BD	51	return IRQ_HANDLED;
	52	}
	53
7d12e780	54	static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
1add6781 BD	55	{
	56	struct rtc_device *rdev = id;
	57
ab6a2d70	58	rtc_update_irq(rdev, tick_count++, RTC_PF \| RTC_IRQF);
1add6781 BD	59	return IRQ_HANDLED;
	60	}
	61
	62	/* Update control registers */
	63	static void s3c_rtc_setaie(int to)
	64	{
	65	unsigned int tmp;
	66
2a4e2b87	67	pr_debug("%s: aie=%d\n", __func__, to);
1add6781	68
9a654518	69	tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
1add6781 BD	70
	71	if (to)
	72	tmp \|= S3C2410_RTCALM_ALMEN;
	73
9a654518	74	writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
1add6781 BD	75	}
	76
	77	static void s3c_rtc_setpie(int to)
	78	{
	79	unsigned int tmp;
	80
2a4e2b87	81	pr_debug("%s: pie=%d\n", __func__, to);
1add6781 BD	82
1add6781 BD	83	spin_lock_irq(&s3c_rtc_pie_lock);
9a654518	84	tmp = readb(s3c_rtc_base + S3C2410_TICNT) & ~S3C2410_TICNT_ENABLE;
1add6781 BD	85
	86	if (to)
	87	tmp \|= S3C2410_TICNT_ENABLE;
	88
9a654518	89	writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
1add6781 BD	90	spin_unlock_irq(&s3c_rtc_pie_lock);
	91	}
	92
	93	static void s3c_rtc_setfreq(int freq)
	94	{
	95	unsigned int tmp;
	96
	97	spin_lock_irq(&s3c_rtc_pie_lock);
9a654518	98	tmp = readb(s3c_rtc_base + S3C2410_TICNT) & S3C2410_TICNT_ENABLE;
1add6781 BD	99
	100	s3c_rtc_freq = freq;
	101
	102	tmp \|= (128 / freq)-1;
	103
9a654518	104	writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
1add6781 BD	105	spin_unlock_irq(&s3c_rtc_pie_lock);
	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 BD	269
1add6781 BD	270	if (0) {
9a654518	271	alrm_en = readb(base + S3C2410_RTCALM);
1add6781	272	alrm_en &= ~S3C2410_RTCALM_ALMEN;
9a654518	273	writeb(alrm_en, base + S3C2410_RTCALM);
1add6781 BD	274	disable_irq_wake(s3c_rtc_alarmno);
	275	}
	276
	277	if (alrm->enabled)
	278	enable_irq_wake(s3c_rtc_alarmno);
	279	else
	280	disable_irq_wake(s3c_rtc_alarmno);
	281
	282	return 0;
	283	}
	284
	285	static int s3c_rtc_ioctl(struct device *dev,
	286	unsigned int cmd, unsigned long arg)
	287	{
	288	unsigned int ret = -ENOIOCTLCMD;
	289
	290	switch (cmd) {
	291	case RTC_AIE_OFF:
	292	case RTC_AIE_ON:
	293	s3c_rtc_setaie((cmd == RTC_AIE_ON) ? 1 : 0);
	294	ret = 0;
	295	break;
	296
	297	case RTC_PIE_OFF:
	298	case RTC_PIE_ON:
	299	tick_count = 0;
	300	s3c_rtc_setpie((cmd == RTC_PIE_ON) ? 1 : 0);
	301	ret = 0;
	302	break;
	303
	304	case RTC_IRQP_READ:
	305	ret = put_user(s3c_rtc_freq, (unsigned long __user *)arg);
	306	break;
	307
	308	case RTC_IRQP_SET:
9974b6ea	309	if (!is_power_of_2(arg)) {
1add6781 BD	310	ret = -EINVAL;
	311	goto exit;
	312	}
	313
	314	pr_debug("s3c2410_rtc: setting frequency %ld\n", arg);
	315
	316	s3c_rtc_setfreq(arg);
	317	ret = 0;
	318	break;
	319
	320	case RTC_UIE_ON:
	321	case RTC_UIE_OFF:
	322	ret = -EINVAL;
	323	}
	324
	325	exit:
	326	return ret;
	327	}
	328
	329	static int s3c_rtc_proc(struct device dev, struct seq_file seq)
	330	{
9a654518	331	unsigned int ticnt = readb(s3c_rtc_base + S3C2410_TICNT);
1add6781	332
1add6781 BD	333	seq_printf(seq, "periodic_IRQ\t: %s\n",
	334	(ticnt & S3C2410_TICNT_ENABLE) ? "yes" : "no" );
	335
	336	seq_printf(seq, "periodic_freq\t: %d\n", s3c_rtc_freq);
	337
	338	return 0;
	339	}
	340
	341	static int s3c_rtc_open(struct device *dev)
	342	{
	343	struct platform_device *pdev = to_platform_device(dev);
	344	struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
	345	int ret;
	346
	347	ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq,
38515e90	348	IRQF_DISABLED, "s3c2410-rtc alarm", rtc_dev);
1add6781 BD	349
	350	if (ret) {
	351	dev_err(dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret);
	352	return ret;
	353	}
	354
	355	ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq,
38515e90	356	IRQF_DISABLED, "s3c2410-rtc tick", rtc_dev);
1add6781 BD	357
	358	if (ret) {
	359	dev_err(dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret);
	360	goto tick_err;
	361	}
	362
	363	return ret;
	364
	365	tick_err:
	366	free_irq(s3c_rtc_alarmno, rtc_dev);
	367	return ret;
	368	}
	369
	370	static void s3c_rtc_release(struct device *dev)
	371	{
	372	struct platform_device *pdev = to_platform_device(dev);
	373	struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
	374
	375	/* do not clear AIE here, it may be needed for wake */
	376
	377	s3c_rtc_setpie(0);
	378	free_irq(s3c_rtc_alarmno, rtc_dev);
	379	free_irq(s3c_rtc_tickno, rtc_dev);
	380	}
	381
ff8371ac	382	static const struct rtc_class_ops s3c_rtcops = {
1add6781 BD	383	.open = s3c_rtc_open,
	384	.release = s3c_rtc_release,
	385	.ioctl = s3c_rtc_ioctl,
	386	.read_time = s3c_rtc_gettime,
	387	.set_time = s3c_rtc_settime,
	388	.read_alarm = s3c_rtc_getalarm,
	389	.set_alarm = s3c_rtc_setalarm,
	390	.proc = s3c_rtc_proc,
	391	};
	392
	393	static void s3c_rtc_enable(struct platform_device *pdev, int en)
	394	{
9a654518	395	void __iomem *base = s3c_rtc_base;
1add6781 BD	396	unsigned int tmp;
	397
	398	if (s3c_rtc_base == NULL)
	399	return;
	400
	401	if (!en) {
9a654518 BD	402	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	403	writeb(tmp & ~S3C2410_RTCCON_RTCEN, base + S3C2410_RTCCON);
1add6781	404
9a654518 BD	405	tmp = readb(base + S3C2410_TICNT);
9a654518 BD	406	writeb(tmp & ~S3C2410_TICNT_ENABLE, base + S3C2410_TICNT);
1add6781 BD	407	} else {
	408	/* re-enable the device, and check it is ok */
	409
9a654518	410	if ((readb(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0){
1add6781 BD	411	dev_info(&pdev->dev, "rtc disabled, re-enabling\n");
1add6781 BD	412
9a654518 BD	413	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	414	writeb(tmp\|S3C2410_RTCCON_RTCEN, base+S3C2410_RTCCON);
1add6781 BD	415	}
1add6781 BD	416
9a654518	417	if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)){
1add6781 BD	418	dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n");
1add6781 BD	419
9a654518 BD	420	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	421	writeb(tmp& ~S3C2410_RTCCON_CNTSEL, base+S3C2410_RTCCON);
1add6781 BD	422	}
1add6781 BD	423
9a654518	424	if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)){
1add6781 BD	425	dev_info(&pdev->dev, "removing RTCCON_CLKRST\n");
1add6781 BD	426
9a654518 BD	427	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	428	writeb(tmp & ~S3C2410_RTCCON_CLKRST, base+S3C2410_RTCCON);
1add6781 BD	429	}
	430	}
	431	}
	432
4cd0c5c4	433	static int __devexit s3c_rtc_remove(struct platform_device *dev)
1add6781 BD	434	{
	435	struct rtc_device *rtc = platform_get_drvdata(dev);
	436
	437	platform_set_drvdata(dev, NULL);
	438	rtc_device_unregister(rtc);
	439
	440	s3c_rtc_setpie(0);
	441	s3c_rtc_setaie(0);
	442
	443	iounmap(s3c_rtc_base);
	444	release_resource(s3c_rtc_mem);
	445	kfree(s3c_rtc_mem);
	446
	447	return 0;
	448	}
	449
4cd0c5c4	450	static int __devinit s3c_rtc_probe(struct platform_device *pdev)
1add6781 BD	451	{
	452	struct rtc_device *rtc;
	453	struct resource *res;
	454	int ret;
	455
2a4e2b87	456	pr_debug("%s: probe=%p\n", __func__, pdev);
1add6781 BD	457
	458	/* find the IRQs */
	459
	460	s3c_rtc_tickno = platform_get_irq(pdev, 1);
	461	if (s3c_rtc_tickno < 0) {
	462	dev_err(&pdev->dev, "no irq for rtc tick\n");
	463	return -ENOENT;
	464	}
	465
	466	s3c_rtc_alarmno = platform_get_irq(pdev, 0);
	467	if (s3c_rtc_alarmno < 0) {
	468	dev_err(&pdev->dev, "no irq for alarm\n");
	469	return -ENOENT;
	470	}
	471
	472	pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
	473	s3c_rtc_tickno, s3c_rtc_alarmno);
	474
	475	/* get the memory region */
	476
	477	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	478	if (res == NULL) {
	479	dev_err(&pdev->dev, "failed to get memory region resource\n");
	480	return -ENOENT;
	481	}
	482
	483	s3c_rtc_mem = request_mem_region(res->start,
9a654518 BD	484	res->end-res->start+1,
9a654518 BD	485	pdev->name);
1add6781 BD	486
	487	if (s3c_rtc_mem == NULL) {
	488	dev_err(&pdev->dev, "failed to reserve memory region\n");
	489	ret = -ENOENT;
	490	goto err_nores;
	491	}
	492
	493	s3c_rtc_base = ioremap(res->start, res->end - res->start + 1);
	494	if (s3c_rtc_base == NULL) {
	495	dev_err(&pdev->dev, "failed ioremap()\n");
	496	ret = -EINVAL;
	497	goto err_nomap;
	498	}
	499
	500	/* check to see if everything is setup correctly */
	501
	502	s3c_rtc_enable(pdev, 1);
	503
9a654518 BD	504	pr_debug("s3c2410_rtc: RTCCON=%02x\n",
9a654518 BD	505	readb(s3c_rtc_base + S3C2410_RTCCON));
1add6781 BD	506
	507	s3c_rtc_setfreq(s3c_rtc_freq);
	508
	509	/* register RTC and exit */
	510
	511	rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops,
	512	THIS_MODULE);
	513
	514	if (IS_ERR(rtc)) {
	515	dev_err(&pdev->dev, "cannot attach rtc\n");
	516	ret = PTR_ERR(rtc);
	517	goto err_nortc;
	518	}
	519
	520	rtc->max_user_freq = 128;
	521
	522	platform_set_drvdata(pdev, rtc);
	523	return 0;
	524
	525	err_nortc:
	526	s3c_rtc_enable(pdev, 0);
	527	iounmap(s3c_rtc_base);
	528
	529	err_nomap:
	530	release_resource(s3c_rtc_mem);
	531
	532	err_nores:
	533	return ret;
	534	}
	535
	536	#ifdef CONFIG_PM
	537
	538	/* RTC Power management control */
	539
1add6781 BD	540	static int ticnt_save;
	541
	542	static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
	543	{
1add6781	544	/* save TICNT for anyone using periodic interrupts */
9a654518	545	ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
1add6781	546	s3c_rtc_enable(pdev, 0);
1add6781 BD	547	return 0;
	548	}
	549
	550	static int s3c_rtc_resume(struct platform_device *pdev)
	551	{
1add6781	552	s3c_rtc_enable(pdev, 1);
9a654518	553	writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
1add6781 BD	554	return 0;
	555	}
	556	#else
	557	#define s3c_rtc_suspend NULL
	558	#define s3c_rtc_resume NULL
	559	#endif
	560
	561	static struct platform_driver s3c2410_rtcdrv = {
	562	.probe = s3c_rtc_probe,
4cd0c5c4	563	.remove = __devexit_p(s3c_rtc_remove),
1add6781 BD	564	.suspend = s3c_rtc_suspend,
	565	.resume = s3c_rtc_resume,
	566	.driver = {
	567	.name = "s3c2410-rtc",
	568	.owner = THIS_MODULE,
	569	},
	570	};
	571
	572	static char __initdata banner[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";
	573
	574	static int __init s3c_rtc_init(void)
	575	{
	576	printk(banner);
	577	return platform_driver_register(&s3c2410_rtcdrv);
	578	}
	579
	580	static void __exit s3c_rtc_exit(void)
	581	{
	582	platform_driver_unregister(&s3c2410_rtcdrv);
	583	}
	584
	585	module_init(s3c_rtc_init);
	586	module_exit(s3c_rtc_exit);
	587
	588	MODULE_DESCRIPTION("Samsung S3C RTC Driver");
	589	MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
	590	MODULE_LICENSE("GPL");
ad28a07b	591	MODULE_ALIAS("platform:s3c2410-rtc");