[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 <asm/hardware.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/rtc.h>

#include <asm/mach/time.h>

#include <asm/arch/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->class_dev, 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->class_dev, 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", __FUNCTION__, 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", __FUNCTION__, 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:
		/* check for power of 2 */

		if ((arg & (arg-1)) != 0 || arg < 1) {
			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 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 s3c_rtc_probe(struct platform_device *pdev)
{
	struct rtc_device *rtc;
	struct resource *res;
	int ret;

	pr_debug("%s: probe=%p\n", __FUNCTION__, 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 struct timespec s3c_rtc_delta;

static int ticnt_save;

static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
{
	struct rtc_time tm;
	struct timespec time;

	time.tv_nsec = 0;

	/* save TICNT for anyone using periodic interrupts */

	ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);

	/* calculate time delta for suspend */

	s3c_rtc_gettime(&pdev->dev, &tm);
	rtc_tm_to_time(&tm, &time.tv_sec);
	save_time_delta(&s3c_rtc_delta, &time);
	s3c_rtc_enable(pdev, 0);

	return 0;
}

static int s3c_rtc_resume(struct platform_device *pdev)
{
	struct rtc_time tm;
	struct timespec time;

	time.tv_nsec = 0;

	s3c_rtc_enable(pdev, 1);
	s3c_rtc_gettime(&pdev->dev, &tm);
	rtc_tm_to_time(&tm, &time.tv_sec);
	restore_time_delta(&s3c_rtc_delta, &time);

	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		= 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");
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>
	23
	24	#include <asm/hardware.h>
	25	#include <asm/uaccess.h>
	26	#include <asm/io.h>
	27	#include <asm/irq.h>
	28	#include <asm/rtc.h>
	29
	30	#include <asm/mach/time.h>
	31
	32	#include <asm/arch/regs-rtc.h>
	33
	34	/* I have yet to find an S3C implementation with more than one
	35	* of these rtc blocks in */
	36
	37	static struct resource *s3c_rtc_mem;
	38
	39	static void __iomem *s3c_rtc_base;
	40	static int s3c_rtc_alarmno = NO_IRQ;
	41	static int s3c_rtc_tickno = NO_IRQ;
	42	static int s3c_rtc_freq = 1;
	43
	44	static DEFINE_SPINLOCK(s3c_rtc_pie_lock);
	45	static unsigned int tick_count;
	46
	47	/* IRQ Handlers */
	48
7d12e780	49	static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
1add6781 BD	50	{
	51	struct rtc_device *rdev = id;
	52
	53	rtc_update_irq(&rdev->class_dev, 1, RTC_AF \| RTC_IRQF);
	54	return IRQ_HANDLED;
	55	}
	56
7d12e780	57	static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
1add6781 BD	58	{
	59	struct rtc_device *rdev = id;
	60
	61	rtc_update_irq(&rdev->class_dev, tick_count++, RTC_PF \| RTC_IRQF);
	62	return IRQ_HANDLED;
	63	}
	64
	65	/* Update control registers */
	66	static void s3c_rtc_setaie(int to)
	67	{
	68	unsigned int tmp;
	69
	70	pr_debug("%s: aie=%d\n", __FUNCTION__, to);
	71
9a654518	72	tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
1add6781 BD	73
	74	if (to)
	75	tmp \|= S3C2410_RTCALM_ALMEN;
	76
9a654518	77	writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
1add6781 BD	78	}
	79
	80	static void s3c_rtc_setpie(int to)
	81	{
	82	unsigned int tmp;
	83
	84	pr_debug("%s: pie=%d\n", __FUNCTION__, to);
	85
	86	spin_lock_irq(&s3c_rtc_pie_lock);
9a654518	87	tmp = readb(s3c_rtc_base + S3C2410_TICNT) & ~S3C2410_TICNT_ENABLE;
1add6781 BD	88
	89	if (to)
	90	tmp \|= S3C2410_TICNT_ENABLE;
	91
9a654518	92	writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
1add6781 BD	93	spin_unlock_irq(&s3c_rtc_pie_lock);
	94	}
	95
	96	static void s3c_rtc_setfreq(int freq)
	97	{
	98	unsigned int tmp;
	99
	100	spin_lock_irq(&s3c_rtc_pie_lock);
9a654518	101	tmp = readb(s3c_rtc_base + S3C2410_TICNT) & S3C2410_TICNT_ENABLE;
1add6781 BD	102
	103	s3c_rtc_freq = freq;
	104
	105	tmp \|= (128 / freq)-1;
	106
9a654518	107	writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
1add6781 BD	108	spin_unlock_irq(&s3c_rtc_pie_lock);
	109	}
	110
	111	/* Time read/write */
	112
	113	static int s3c_rtc_gettime(struct device dev, struct rtc_time rtc_tm)
	114	{
	115	unsigned int have_retried = 0;
9a654518	116	void __iomem *base = s3c_rtc_base;
1add6781 BD	117
1add6781 BD	118	retry_get_time:
9a654518 BD	119	rtc_tm->tm_min = readb(base + S3C2410_RTCMIN);
	120	rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR);
	121	rtc_tm->tm_mday = readb(base + S3C2410_RTCDATE);
	122	rtc_tm->tm_mon = readb(base + S3C2410_RTCMON);
	123	rtc_tm->tm_year = readb(base + S3C2410_RTCYEAR);
	124	rtc_tm->tm_sec = readb(base + S3C2410_RTCSEC);
1add6781 BD	125
	126	/* the only way to work out wether the system was mid-update
	127	* when we read it is to check the second counter, and if it
	128	* is zero, then we re-try the entire read
	129	*/
	130
	131	if (rtc_tm->tm_sec == 0 && !have_retried) {
	132	have_retried = 1;
	133	goto retry_get_time;
	134	}
	135
	136	pr_debug("read time %02x.%02x.%02x %02x/%02x/%02x\n",
	137	rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
	138	rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
	139
	140	BCD_TO_BIN(rtc_tm->tm_sec);
	141	BCD_TO_BIN(rtc_tm->tm_min);
	142	BCD_TO_BIN(rtc_tm->tm_hour);
	143	BCD_TO_BIN(rtc_tm->tm_mday);
	144	BCD_TO_BIN(rtc_tm->tm_mon);
	145	BCD_TO_BIN(rtc_tm->tm_year);
	146
	147	rtc_tm->tm_year += 100;
	148	rtc_tm->tm_mon -= 1;
	149
	150	return 0;
	151	}
	152
	153	static int s3c_rtc_settime(struct device dev, struct rtc_time tm)
	154	{
9a654518	155	void __iomem *base = s3c_rtc_base;
641741e0	156	int year = tm->tm_year - 100;
9a654518	157
641741e0 BD	158	pr_debug("set time %02d.%02d.%02d %02d/%02d/%02d\n",
	159	tm->tm_year, tm->tm_mon, tm->tm_mday,
	160	tm->tm_hour, tm->tm_min, tm->tm_sec);
	161
	162	/* we get around y2k by simply not supporting it */
1add6781	163
641741e0	164	if (year < 0 \|\| year >= 100) {
9a654518	165	dev_err(dev, "rtc only supports 100 years\n");
1add6781	166	return -EINVAL;
9a654518 BD	167	}
9a654518 BD	168
9a654518 BD	169	writeb(BIN2BCD(tm->tm_sec), base + S3C2410_RTCSEC);
	170	writeb(BIN2BCD(tm->tm_min), base + S3C2410_RTCMIN);
	171	writeb(BIN2BCD(tm->tm_hour), base + S3C2410_RTCHOUR);
	172	writeb(BIN2BCD(tm->tm_mday), base + S3C2410_RTCDATE);
	173	writeb(BIN2BCD(tm->tm_mon + 1), base + S3C2410_RTCMON);
641741e0	174	writeb(BIN2BCD(year), base + S3C2410_RTCYEAR);
1add6781 BD	175
	176	return 0;
	177	}
	178
	179	static int s3c_rtc_getalarm(struct device dev, struct rtc_wkalrm alrm)
	180	{
	181	struct rtc_time *alm_tm = &alrm->time;
9a654518	182	void __iomem *base = s3c_rtc_base;
1add6781 BD	183	unsigned int alm_en;
1add6781 BD	184
9a654518 BD	185	alm_tm->tm_sec = readb(base + S3C2410_ALMSEC);
	186	alm_tm->tm_min = readb(base + S3C2410_ALMMIN);
	187	alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR);
	188	alm_tm->tm_mon = readb(base + S3C2410_ALMMON);
	189	alm_tm->tm_mday = readb(base + S3C2410_ALMDATE);
	190	alm_tm->tm_year = readb(base + S3C2410_ALMYEAR);
1add6781	191
9a654518	192	alm_en = readb(base + S3C2410_RTCALM);
1add6781	193
a2db8dfc DB	194	alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
a2db8dfc DB	195
1add6781 BD	196	pr_debug("read alarm %02x %02x.%02x.%02x %02x/%02x/%02x\n",
	197	alm_en,
	198	alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
	199	alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
	200
	201
	202	/* decode the alarm enable field */
	203
	204	if (alm_en & S3C2410_RTCALM_SECEN)
	205	BCD_TO_BIN(alm_tm->tm_sec);
	206	else
	207	alm_tm->tm_sec = 0xff;
	208
	209	if (alm_en & S3C2410_RTCALM_MINEN)
	210	BCD_TO_BIN(alm_tm->tm_min);
	211	else
	212	alm_tm->tm_min = 0xff;
	213
	214	if (alm_en & S3C2410_RTCALM_HOUREN)
	215	BCD_TO_BIN(alm_tm->tm_hour);
	216	else
	217	alm_tm->tm_hour = 0xff;
	218
	219	if (alm_en & S3C2410_RTCALM_DAYEN)
	220	BCD_TO_BIN(alm_tm->tm_mday);
	221	else
	222	alm_tm->tm_mday = 0xff;
	223
	224	if (alm_en & S3C2410_RTCALM_MONEN) {
	225	BCD_TO_BIN(alm_tm->tm_mon);
	226	alm_tm->tm_mon -= 1;
	227	} else {
	228	alm_tm->tm_mon = 0xff;
	229	}
	230
	231	if (alm_en & S3C2410_RTCALM_YEAREN)
	232	BCD_TO_BIN(alm_tm->tm_year);
	233	else
	234	alm_tm->tm_year = 0xffff;
	235
	236	return 0;
	237	}
	238
	239	static int s3c_rtc_setalarm(struct device dev, struct rtc_wkalrm alrm)
	240	{
	241	struct rtc_time *tm = &alrm->time;
9a654518	242	void __iomem *base = s3c_rtc_base;
1add6781 BD	243	unsigned int alrm_en;
	244
	245	pr_debug("s3c_rtc_setalarm: %d, %02x/%02x/%02x %02x.%02x.%02x\n",
	246	alrm->enabled,
	247	tm->tm_mday & 0xff, tm->tm_mon & 0xff, tm->tm_year & 0xff,
	248	tm->tm_hour & 0xff, tm->tm_min & 0xff, tm->tm_sec);
	249
	250
9a654518 BD	251	alrm_en = readb(base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
9a654518 BD	252	writeb(0x00, base + S3C2410_RTCALM);
1add6781 BD	253
	254	if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
	255	alrm_en \|= S3C2410_RTCALM_SECEN;
9a654518	256	writeb(BIN2BCD(tm->tm_sec), base + S3C2410_ALMSEC);
1add6781 BD	257	}
	258
	259	if (tm->tm_min < 60 && tm->tm_min >= 0) {
	260	alrm_en \|= S3C2410_RTCALM_MINEN;
9a654518	261	writeb(BIN2BCD(tm->tm_min), base + S3C2410_ALMMIN);
1add6781 BD	262	}
	263
	264	if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
	265	alrm_en \|= S3C2410_RTCALM_HOUREN;
9a654518	266	writeb(BIN2BCD(tm->tm_hour), base + S3C2410_ALMHOUR);
1add6781 BD	267	}
	268
	269	pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en);
	270
9a654518	271	writeb(alrm_en, base + S3C2410_RTCALM);
1add6781 BD	272
1add6781 BD	273	if (0) {
9a654518	274	alrm_en = readb(base + S3C2410_RTCALM);
1add6781	275	alrm_en &= ~S3C2410_RTCALM_ALMEN;
9a654518	276	writeb(alrm_en, base + S3C2410_RTCALM);
1add6781 BD	277	disable_irq_wake(s3c_rtc_alarmno);
	278	}
	279
	280	if (alrm->enabled)
	281	enable_irq_wake(s3c_rtc_alarmno);
	282	else
	283	disable_irq_wake(s3c_rtc_alarmno);
	284
	285	return 0;
	286	}
	287
	288	static int s3c_rtc_ioctl(struct device *dev,
	289	unsigned int cmd, unsigned long arg)
	290	{
	291	unsigned int ret = -ENOIOCTLCMD;
	292
	293	switch (cmd) {
	294	case RTC_AIE_OFF:
	295	case RTC_AIE_ON:
	296	s3c_rtc_setaie((cmd == RTC_AIE_ON) ? 1 : 0);
	297	ret = 0;
	298	break;
	299
	300	case RTC_PIE_OFF:
	301	case RTC_PIE_ON:
	302	tick_count = 0;
	303	s3c_rtc_setpie((cmd == RTC_PIE_ON) ? 1 : 0);
	304	ret = 0;
	305	break;
	306
	307	case RTC_IRQP_READ:
	308	ret = put_user(s3c_rtc_freq, (unsigned long __user *)arg);
	309	break;
	310
	311	case RTC_IRQP_SET:
	312	/* check for power of 2 */
	313
	314	if ((arg & (arg-1)) != 0 \|\| arg < 1) {
	315	ret = -EINVAL;
	316	goto exit;
	317	}
	318
	319	pr_debug("s3c2410_rtc: setting frequency %ld\n", arg);
	320
	321	s3c_rtc_setfreq(arg);
	322	ret = 0;
	323	break;
	324
	325	case RTC_UIE_ON:
	326	case RTC_UIE_OFF:
	327	ret = -EINVAL;
	328	}
	329
	330	exit:
	331	return ret;
	332	}
	333
	334	static int s3c_rtc_proc(struct device dev, struct seq_file seq)
	335	{
9a654518	336	unsigned int ticnt = readb(s3c_rtc_base + S3C2410_TICNT);
1add6781	337
1add6781 BD	338	seq_printf(seq, "periodic_IRQ\t: %s\n",
	339	(ticnt & S3C2410_TICNT_ENABLE) ? "yes" : "no" );
	340
	341	seq_printf(seq, "periodic_freq\t: %d\n", s3c_rtc_freq);
	342
	343	return 0;
	344	}
	345
	346	static int s3c_rtc_open(struct device *dev)
	347	{
	348	struct platform_device *pdev = to_platform_device(dev);
	349	struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
	350	int ret;
	351
	352	ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq,
38515e90	353	IRQF_DISABLED, "s3c2410-rtc alarm", rtc_dev);
1add6781 BD	354
	355	if (ret) {
	356	dev_err(dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret);
	357	return ret;
	358	}
	359
	360	ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq,
38515e90	361	IRQF_DISABLED, "s3c2410-rtc tick", rtc_dev);
1add6781 BD	362
	363	if (ret) {
	364	dev_err(dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret);
	365	goto tick_err;
	366	}
	367
	368	return ret;
	369
	370	tick_err:
	371	free_irq(s3c_rtc_alarmno, rtc_dev);
	372	return ret;
	373	}
	374
	375	static void s3c_rtc_release(struct device *dev)
	376	{
	377	struct platform_device *pdev = to_platform_device(dev);
	378	struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
	379
	380	/* do not clear AIE here, it may be needed for wake */
	381
	382	s3c_rtc_setpie(0);
	383	free_irq(s3c_rtc_alarmno, rtc_dev);
	384	free_irq(s3c_rtc_tickno, rtc_dev);
	385	}
	386
ff8371ac	387	static const struct rtc_class_ops s3c_rtcops = {
1add6781 BD	388	.open = s3c_rtc_open,
	389	.release = s3c_rtc_release,
	390	.ioctl = s3c_rtc_ioctl,
	391	.read_time = s3c_rtc_gettime,
	392	.set_time = s3c_rtc_settime,
	393	.read_alarm = s3c_rtc_getalarm,
	394	.set_alarm = s3c_rtc_setalarm,
	395	.proc = s3c_rtc_proc,
	396	};
	397
	398	static void s3c_rtc_enable(struct platform_device *pdev, int en)
	399	{
9a654518	400	void __iomem *base = s3c_rtc_base;
1add6781 BD	401	unsigned int tmp;
	402
	403	if (s3c_rtc_base == NULL)
	404	return;
	405
	406	if (!en) {
9a654518 BD	407	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	408	writeb(tmp & ~S3C2410_RTCCON_RTCEN, base + S3C2410_RTCCON);
1add6781	409
9a654518 BD	410	tmp = readb(base + S3C2410_TICNT);
9a654518 BD	411	writeb(tmp & ~S3C2410_TICNT_ENABLE, base + S3C2410_TICNT);
1add6781 BD	412	} else {
	413	/* re-enable the device, and check it is ok */
	414
9a654518	415	if ((readb(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0){
1add6781 BD	416	dev_info(&pdev->dev, "rtc disabled, re-enabling\n");
1add6781 BD	417
9a654518 BD	418	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	419	writeb(tmp\|S3C2410_RTCCON_RTCEN, base+S3C2410_RTCCON);
1add6781 BD	420	}
1add6781 BD	421
9a654518	422	if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)){
1add6781 BD	423	dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n");
1add6781 BD	424
9a654518 BD	425	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	426	writeb(tmp& ~S3C2410_RTCCON_CNTSEL, base+S3C2410_RTCCON);
1add6781 BD	427	}
1add6781 BD	428
9a654518	429	if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)){
1add6781 BD	430	dev_info(&pdev->dev, "removing RTCCON_CLKRST\n");
1add6781 BD	431
9a654518 BD	432	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	433	writeb(tmp & ~S3C2410_RTCCON_CLKRST, base+S3C2410_RTCCON);
1add6781 BD	434	}
	435	}
	436	}
	437
	438	static int s3c_rtc_remove(struct platform_device *dev)
	439	{
	440	struct rtc_device *rtc = platform_get_drvdata(dev);
	441
	442	platform_set_drvdata(dev, NULL);
	443	rtc_device_unregister(rtc);
	444
	445	s3c_rtc_setpie(0);
	446	s3c_rtc_setaie(0);
	447
	448	iounmap(s3c_rtc_base);
	449	release_resource(s3c_rtc_mem);
	450	kfree(s3c_rtc_mem);
	451
	452	return 0;
	453	}
	454
	455	static int s3c_rtc_probe(struct platform_device *pdev)
	456	{
	457	struct rtc_device *rtc;
	458	struct resource *res;
	459	int ret;
	460
	461	pr_debug("%s: probe=%p\n", __FUNCTION__, pdev);
	462
	463	/* find the IRQs */
	464
	465	s3c_rtc_tickno = platform_get_irq(pdev, 1);
	466	if (s3c_rtc_tickno < 0) {
	467	dev_err(&pdev->dev, "no irq for rtc tick\n");
	468	return -ENOENT;
	469	}
	470
	471	s3c_rtc_alarmno = platform_get_irq(pdev, 0);
	472	if (s3c_rtc_alarmno < 0) {
	473	dev_err(&pdev->dev, "no irq for alarm\n");
	474	return -ENOENT;
	475	}
	476
	477	pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
	478	s3c_rtc_tickno, s3c_rtc_alarmno);
	479
	480	/* get the memory region */
	481
	482	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	483	if (res == NULL) {
	484	dev_err(&pdev->dev, "failed to get memory region resource\n");
	485	return -ENOENT;
	486	}
	487
	488	s3c_rtc_mem = request_mem_region(res->start,
9a654518 BD	489	res->end-res->start+1,
9a654518 BD	490	pdev->name);
1add6781 BD	491
	492	if (s3c_rtc_mem == NULL) {
	493	dev_err(&pdev->dev, "failed to reserve memory region\n");
	494	ret = -ENOENT;
	495	goto err_nores;
	496	}
	497
	498	s3c_rtc_base = ioremap(res->start, res->end - res->start + 1);
	499	if (s3c_rtc_base == NULL) {
	500	dev_err(&pdev->dev, "failed ioremap()\n");
	501	ret = -EINVAL;
	502	goto err_nomap;
	503	}
	504
	505	/* check to see if everything is setup correctly */
	506
	507	s3c_rtc_enable(pdev, 1);
	508
9a654518 BD	509	pr_debug("s3c2410_rtc: RTCCON=%02x\n",
9a654518 BD	510	readb(s3c_rtc_base + S3C2410_RTCCON));
1add6781 BD	511
	512	s3c_rtc_setfreq(s3c_rtc_freq);
	513
	514	/* register RTC and exit */
	515
	516	rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops,
	517	THIS_MODULE);
	518
	519	if (IS_ERR(rtc)) {
	520	dev_err(&pdev->dev, "cannot attach rtc\n");
	521	ret = PTR_ERR(rtc);
	522	goto err_nortc;
	523	}
	524
	525	rtc->max_user_freq = 128;
	526
	527	platform_set_drvdata(pdev, rtc);
	528	return 0;
	529
	530	err_nortc:
	531	s3c_rtc_enable(pdev, 0);
	532	iounmap(s3c_rtc_base);
	533
	534	err_nomap:
	535	release_resource(s3c_rtc_mem);
	536
	537	err_nores:
	538	return ret;
	539	}
	540
	541	#ifdef CONFIG_PM
	542
	543	/* RTC Power management control */
	544
	545	static struct timespec s3c_rtc_delta;
	546
	547	static int ticnt_save;
	548
	549	static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
	550	{
	551	struct rtc_time tm;
	552	struct timespec time;
	553
	554	time.tv_nsec = 0;
	555
	556	/* save TICNT for anyone using periodic interrupts */
	557
9a654518	558	ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
1add6781 BD	559
	560	/* calculate time delta for suspend */
	561
	562	s3c_rtc_gettime(&pdev->dev, &tm);
	563	rtc_tm_to_time(&tm, &time.tv_sec);
	564	save_time_delta(&s3c_rtc_delta, &time);
	565	s3c_rtc_enable(pdev, 0);
	566
	567	return 0;
	568	}
	569
	570	static int s3c_rtc_resume(struct platform_device *pdev)
	571	{
	572	struct rtc_time tm;
	573	struct timespec time;
	574
	575	time.tv_nsec = 0;
	576
	577	s3c_rtc_enable(pdev, 1);
	578	s3c_rtc_gettime(&pdev->dev, &tm);
	579	rtc_tm_to_time(&tm, &time.tv_sec);
	580	restore_time_delta(&s3c_rtc_delta, &time);
	581
9a654518	582	writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
1add6781 BD	583	return 0;
	584	}
	585	#else
	586	#define s3c_rtc_suspend NULL
	587	#define s3c_rtc_resume NULL
	588	#endif
	589
	590	static struct platform_driver s3c2410_rtcdrv = {
	591	.probe = s3c_rtc_probe,
	592	.remove = s3c_rtc_remove,
	593	.suspend = s3c_rtc_suspend,
	594	.resume = s3c_rtc_resume,
	595	.driver = {
	596	.name = "s3c2410-rtc",
	597	.owner = THIS_MODULE,
	598	},
	599	};
	600
	601	static char __initdata banner[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";
	602
	603	static int __init s3c_rtc_init(void)
	604	{
	605	printk(banner);
	606	return platform_driver_register(&s3c2410_rtcdrv);
	607	}
	608
	609	static void __exit s3c_rtc_exit(void)
	610	{
	611	platform_driver_unregister(&s3c2410_rtcdrv);
	612	}
	613
	614	module_init(s3c_rtc_init);
	615	module_exit(s3c_rtc_exit);
	616
	617	MODULE_DESCRIPTION("Samsung S3C RTC Driver");
	618	MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
	619	MODULE_LICENSE("GPL");