[mirror_ubuntu-zesty-kernel.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/rtc.h>

#include <asm/mach/time.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 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", __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		= 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>
	29	#include <asm/rtc.h>
	30
	31	#include <asm/mach/time.h>
	32
252e4838	33	#include <asm/plat-s3c/regs-rtc.h>
1add6781 BD	34
	35	/* I have yet to find an S3C implementation with more than one
	36	* of these rtc blocks in */
	37
	38	static struct resource *s3c_rtc_mem;
	39
	40	static void __iomem *s3c_rtc_base;
	41	static int s3c_rtc_alarmno = NO_IRQ;
	42	static int s3c_rtc_tickno = NO_IRQ;
	43	static int s3c_rtc_freq = 1;
	44
	45	static DEFINE_SPINLOCK(s3c_rtc_pie_lock);
	46	static unsigned int tick_count;
	47
	48	/* IRQ Handlers */
	49
7d12e780	50	static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
1add6781 BD	51	{
	52	struct rtc_device *rdev = id;
	53
ab6a2d70	54	rtc_update_irq(rdev, 1, RTC_AF \| RTC_IRQF);
1add6781 BD	55	return IRQ_HANDLED;
	56	}
	57
7d12e780	58	static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
1add6781 BD	59	{
	60	struct rtc_device *rdev = id;
	61
ab6a2d70	62	rtc_update_irq(rdev, tick_count++, RTC_PF \| RTC_IRQF);
1add6781 BD	63	return IRQ_HANDLED;
	64	}
	65
	66	/* Update control registers */
	67	static void s3c_rtc_setaie(int to)
	68	{
	69	unsigned int tmp;
	70
2a4e2b87	71	pr_debug("%s: aie=%d\n", __func__, to);
1add6781	72
9a654518	73	tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
1add6781 BD	74
	75	if (to)
	76	tmp \|= S3C2410_RTCALM_ALMEN;
	77
9a654518	78	writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
1add6781 BD	79	}
	80
	81	static void s3c_rtc_setpie(int to)
	82	{
	83	unsigned int tmp;
	84
2a4e2b87	85	pr_debug("%s: pie=%d\n", __func__, to);
1add6781 BD	86
1add6781 BD	87	spin_lock_irq(&s3c_rtc_pie_lock);
9a654518	88	tmp = readb(s3c_rtc_base + S3C2410_TICNT) & ~S3C2410_TICNT_ENABLE;
1add6781 BD	89
	90	if (to)
	91	tmp \|= S3C2410_TICNT_ENABLE;
	92
9a654518	93	writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
1add6781 BD	94	spin_unlock_irq(&s3c_rtc_pie_lock);
	95	}
	96
	97	static void s3c_rtc_setfreq(int freq)
	98	{
	99	unsigned int tmp;
	100
	101	spin_lock_irq(&s3c_rtc_pie_lock);
9a654518	102	tmp = readb(s3c_rtc_base + S3C2410_TICNT) & S3C2410_TICNT_ENABLE;
1add6781 BD	103
	104	s3c_rtc_freq = freq;
	105
	106	tmp \|= (128 / freq)-1;
	107
9a654518	108	writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
1add6781 BD	109	spin_unlock_irq(&s3c_rtc_pie_lock);
	110	}
	111
	112	/* Time read/write */
	113
	114	static int s3c_rtc_gettime(struct device dev, struct rtc_time rtc_tm)
	115	{
	116	unsigned int have_retried = 0;
9a654518	117	void __iomem *base = s3c_rtc_base;
1add6781 BD	118
1add6781 BD	119	retry_get_time:
9a654518 BD	120	rtc_tm->tm_min = readb(base + S3C2410_RTCMIN);
	121	rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR);
	122	rtc_tm->tm_mday = readb(base + S3C2410_RTCDATE);
	123	rtc_tm->tm_mon = readb(base + S3C2410_RTCMON);
	124	rtc_tm->tm_year = readb(base + S3C2410_RTCYEAR);
	125	rtc_tm->tm_sec = readb(base + S3C2410_RTCSEC);
1add6781 BD	126
	127	/* the only way to work out wether the system was mid-update
	128	* when we read it is to check the second counter, and if it
	129	* is zero, then we re-try the entire read
	130	*/
	131
	132	if (rtc_tm->tm_sec == 0 && !have_retried) {
	133	have_retried = 1;
	134	goto retry_get_time;
	135	}
	136
	137	pr_debug("read time %02x.%02x.%02x %02x/%02x/%02x\n",
	138	rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
	139	rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
	140
	141	BCD_TO_BIN(rtc_tm->tm_sec);
	142	BCD_TO_BIN(rtc_tm->tm_min);
	143	BCD_TO_BIN(rtc_tm->tm_hour);
	144	BCD_TO_BIN(rtc_tm->tm_mday);
	145	BCD_TO_BIN(rtc_tm->tm_mon);
	146	BCD_TO_BIN(rtc_tm->tm_year);
	147
	148	rtc_tm->tm_year += 100;
	149	rtc_tm->tm_mon -= 1;
	150
	151	return 0;
	152	}
	153
	154	static int s3c_rtc_settime(struct device dev, struct rtc_time tm)
	155	{
9a654518	156	void __iomem *base = s3c_rtc_base;
641741e0	157	int year = tm->tm_year - 100;
9a654518	158
641741e0 BD	159	pr_debug("set time %02d.%02d.%02d %02d/%02d/%02d\n",
	160	tm->tm_year, tm->tm_mon, tm->tm_mday,
	161	tm->tm_hour, tm->tm_min, tm->tm_sec);
	162
	163	/* we get around y2k by simply not supporting it */
1add6781	164
641741e0	165	if (year < 0 \|\| year >= 100) {
9a654518	166	dev_err(dev, "rtc only supports 100 years\n");
1add6781	167	return -EINVAL;
9a654518 BD	168	}
9a654518 BD	169
9a654518 BD	170	writeb(BIN2BCD(tm->tm_sec), base + S3C2410_RTCSEC);
	171	writeb(BIN2BCD(tm->tm_min), base + S3C2410_RTCMIN);
	172	writeb(BIN2BCD(tm->tm_hour), base + S3C2410_RTCHOUR);
	173	writeb(BIN2BCD(tm->tm_mday), base + S3C2410_RTCDATE);
	174	writeb(BIN2BCD(tm->tm_mon + 1), base + S3C2410_RTCMON);
641741e0	175	writeb(BIN2BCD(year), base + S3C2410_RTCYEAR);
1add6781 BD	176
	177	return 0;
	178	}
	179
	180	static int s3c_rtc_getalarm(struct device dev, struct rtc_wkalrm alrm)
	181	{
	182	struct rtc_time *alm_tm = &alrm->time;
9a654518	183	void __iomem *base = s3c_rtc_base;
1add6781 BD	184	unsigned int alm_en;
1add6781 BD	185
9a654518 BD	186	alm_tm->tm_sec = readb(base + S3C2410_ALMSEC);
	187	alm_tm->tm_min = readb(base + S3C2410_ALMMIN);
	188	alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR);
	189	alm_tm->tm_mon = readb(base + S3C2410_ALMMON);
	190	alm_tm->tm_mday = readb(base + S3C2410_ALMDATE);
	191	alm_tm->tm_year = readb(base + S3C2410_ALMYEAR);
1add6781	192
9a654518	193	alm_en = readb(base + S3C2410_RTCALM);
1add6781	194
a2db8dfc DB	195	alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
a2db8dfc DB	196
1add6781 BD	197	pr_debug("read alarm %02x %02x.%02x.%02x %02x/%02x/%02x\n",
	198	alm_en,
	199	alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
	200	alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
	201
	202
	203	/* decode the alarm enable field */
	204
	205	if (alm_en & S3C2410_RTCALM_SECEN)
	206	BCD_TO_BIN(alm_tm->tm_sec);
	207	else
	208	alm_tm->tm_sec = 0xff;
	209
	210	if (alm_en & S3C2410_RTCALM_MINEN)
	211	BCD_TO_BIN(alm_tm->tm_min);
	212	else
	213	alm_tm->tm_min = 0xff;
	214
	215	if (alm_en & S3C2410_RTCALM_HOUREN)
	216	BCD_TO_BIN(alm_tm->tm_hour);
	217	else
	218	alm_tm->tm_hour = 0xff;
	219
	220	if (alm_en & S3C2410_RTCALM_DAYEN)
	221	BCD_TO_BIN(alm_tm->tm_mday);
	222	else
	223	alm_tm->tm_mday = 0xff;
	224
	225	if (alm_en & S3C2410_RTCALM_MONEN) {
	226	BCD_TO_BIN(alm_tm->tm_mon);
	227	alm_tm->tm_mon -= 1;
	228	} else {
	229	alm_tm->tm_mon = 0xff;
	230	}
	231
	232	if (alm_en & S3C2410_RTCALM_YEAREN)
	233	BCD_TO_BIN(alm_tm->tm_year);
	234	else
	235	alm_tm->tm_year = 0xffff;
	236
	237	return 0;
	238	}
	239
	240	static int s3c_rtc_setalarm(struct device dev, struct rtc_wkalrm alrm)
	241	{
	242	struct rtc_time *tm = &alrm->time;
9a654518	243	void __iomem *base = s3c_rtc_base;
1add6781 BD	244	unsigned int alrm_en;
	245
	246	pr_debug("s3c_rtc_setalarm: %d, %02x/%02x/%02x %02x.%02x.%02x\n",
	247	alrm->enabled,
	248	tm->tm_mday & 0xff, tm->tm_mon & 0xff, tm->tm_year & 0xff,
	249	tm->tm_hour & 0xff, tm->tm_min & 0xff, tm->tm_sec);
	250
	251
9a654518 BD	252	alrm_en = readb(base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
9a654518 BD	253	writeb(0x00, base + S3C2410_RTCALM);
1add6781 BD	254
	255	if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
	256	alrm_en \|= S3C2410_RTCALM_SECEN;
9a654518	257	writeb(BIN2BCD(tm->tm_sec), base + S3C2410_ALMSEC);
1add6781 BD	258	}
	259
	260	if (tm->tm_min < 60 && tm->tm_min >= 0) {
	261	alrm_en \|= S3C2410_RTCALM_MINEN;
9a654518	262	writeb(BIN2BCD(tm->tm_min), base + S3C2410_ALMMIN);
1add6781 BD	263	}
	264
	265	if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
	266	alrm_en \|= S3C2410_RTCALM_HOUREN;
9a654518	267	writeb(BIN2BCD(tm->tm_hour), base + S3C2410_ALMHOUR);
1add6781 BD	268	}
	269
	270	pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en);
	271
9a654518	272	writeb(alrm_en, base + S3C2410_RTCALM);
1add6781 BD	273
1add6781 BD	274	if (0) {
9a654518	275	alrm_en = readb(base + S3C2410_RTCALM);
1add6781	276	alrm_en &= ~S3C2410_RTCALM_ALMEN;
9a654518	277	writeb(alrm_en, base + S3C2410_RTCALM);
1add6781 BD	278	disable_irq_wake(s3c_rtc_alarmno);
	279	}
	280
	281	if (alrm->enabled)
	282	enable_irq_wake(s3c_rtc_alarmno);
	283	else
	284	disable_irq_wake(s3c_rtc_alarmno);
	285
	286	return 0;
	287	}
	288
	289	static int s3c_rtc_ioctl(struct device *dev,
	290	unsigned int cmd, unsigned long arg)
	291	{
	292	unsigned int ret = -ENOIOCTLCMD;
	293
	294	switch (cmd) {
	295	case RTC_AIE_OFF:
	296	case RTC_AIE_ON:
	297	s3c_rtc_setaie((cmd == RTC_AIE_ON) ? 1 : 0);
	298	ret = 0;
	299	break;
	300
	301	case RTC_PIE_OFF:
	302	case RTC_PIE_ON:
	303	tick_count = 0;
	304	s3c_rtc_setpie((cmd == RTC_PIE_ON) ? 1 : 0);
	305	ret = 0;
	306	break;
	307
	308	case RTC_IRQP_READ:
	309	ret = put_user(s3c_rtc_freq, (unsigned long __user *)arg);
	310	break;
	311
	312	case RTC_IRQP_SET:
9974b6ea	313	if (!is_power_of_2(arg)) {
1add6781 BD	314	ret = -EINVAL;
	315	goto exit;
	316	}
	317
	318	pr_debug("s3c2410_rtc: setting frequency %ld\n", arg);
	319
	320	s3c_rtc_setfreq(arg);
	321	ret = 0;
	322	break;
	323
	324	case RTC_UIE_ON:
	325	case RTC_UIE_OFF:
	326	ret = -EINVAL;
	327	}
	328
	329	exit:
	330	return ret;
	331	}
	332
	333	static int s3c_rtc_proc(struct device dev, struct seq_file seq)
	334	{
9a654518	335	unsigned int ticnt = readb(s3c_rtc_base + S3C2410_TICNT);
1add6781	336
1add6781 BD	337	seq_printf(seq, "periodic_IRQ\t: %s\n",
	338	(ticnt & S3C2410_TICNT_ENABLE) ? "yes" : "no" );
	339
	340	seq_printf(seq, "periodic_freq\t: %d\n", s3c_rtc_freq);
	341
	342	return 0;
	343	}
	344
	345	static int s3c_rtc_open(struct device *dev)
	346	{
	347	struct platform_device *pdev = to_platform_device(dev);
	348	struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
	349	int ret;
	350
	351	ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq,
38515e90	352	IRQF_DISABLED, "s3c2410-rtc alarm", rtc_dev);
1add6781 BD	353
	354	if (ret) {
	355	dev_err(dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret);
	356	return ret;
	357	}
	358
	359	ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq,
38515e90	360	IRQF_DISABLED, "s3c2410-rtc tick", rtc_dev);
1add6781 BD	361
	362	if (ret) {
	363	dev_err(dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret);
	364	goto tick_err;
	365	}
	366
	367	return ret;
	368
	369	tick_err:
	370	free_irq(s3c_rtc_alarmno, rtc_dev);
	371	return ret;
	372	}
	373
	374	static void s3c_rtc_release(struct device *dev)
	375	{
	376	struct platform_device *pdev = to_platform_device(dev);
	377	struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
	378
	379	/* do not clear AIE here, it may be needed for wake */
	380
	381	s3c_rtc_setpie(0);
	382	free_irq(s3c_rtc_alarmno, rtc_dev);
	383	free_irq(s3c_rtc_tickno, rtc_dev);
	384	}
	385
ff8371ac	386	static const struct rtc_class_ops s3c_rtcops = {
1add6781 BD	387	.open = s3c_rtc_open,
	388	.release = s3c_rtc_release,
	389	.ioctl = s3c_rtc_ioctl,
	390	.read_time = s3c_rtc_gettime,
	391	.set_time = s3c_rtc_settime,
	392	.read_alarm = s3c_rtc_getalarm,
	393	.set_alarm = s3c_rtc_setalarm,
	394	.proc = s3c_rtc_proc,
	395	};
	396
	397	static void s3c_rtc_enable(struct platform_device *pdev, int en)
	398	{
9a654518	399	void __iomem *base = s3c_rtc_base;
1add6781 BD	400	unsigned int tmp;
	401
	402	if (s3c_rtc_base == NULL)
	403	return;
	404
	405	if (!en) {
9a654518 BD	406	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	407	writeb(tmp & ~S3C2410_RTCCON_RTCEN, base + S3C2410_RTCCON);
1add6781	408
9a654518 BD	409	tmp = readb(base + S3C2410_TICNT);
9a654518 BD	410	writeb(tmp & ~S3C2410_TICNT_ENABLE, base + S3C2410_TICNT);
1add6781 BD	411	} else {
	412	/* re-enable the device, and check it is ok */
	413
9a654518	414	if ((readb(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0){
1add6781 BD	415	dev_info(&pdev->dev, "rtc disabled, re-enabling\n");
1add6781 BD	416
9a654518 BD	417	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	418	writeb(tmp\|S3C2410_RTCCON_RTCEN, base+S3C2410_RTCCON);
1add6781 BD	419	}
1add6781 BD	420
9a654518	421	if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)){
1add6781 BD	422	dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n");
1add6781 BD	423
9a654518 BD	424	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	425	writeb(tmp& ~S3C2410_RTCCON_CNTSEL, base+S3C2410_RTCCON);
1add6781 BD	426	}
1add6781 BD	427
9a654518	428	if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)){
1add6781 BD	429	dev_info(&pdev->dev, "removing RTCCON_CLKRST\n");
1add6781 BD	430
9a654518 BD	431	tmp = readb(base + S3C2410_RTCCON);
9a654518 BD	432	writeb(tmp & ~S3C2410_RTCCON_CLKRST, base+S3C2410_RTCCON);
1add6781 BD	433	}
	434	}
	435	}
	436
	437	static int s3c_rtc_remove(struct platform_device *dev)
	438	{
	439	struct rtc_device *rtc = platform_get_drvdata(dev);
	440
	441	platform_set_drvdata(dev, NULL);
	442	rtc_device_unregister(rtc);
	443
	444	s3c_rtc_setpie(0);
	445	s3c_rtc_setaie(0);
	446
	447	iounmap(s3c_rtc_base);
	448	release_resource(s3c_rtc_mem);
	449	kfree(s3c_rtc_mem);
	450
	451	return 0;
	452	}
	453
	454	static int s3c_rtc_probe(struct platform_device *pdev)
	455	{
	456	struct rtc_device *rtc;
	457	struct resource *res;
	458	int ret;
	459
2a4e2b87	460	pr_debug("%s: probe=%p\n", __func__, pdev);
1add6781 BD	461
	462	/* find the IRQs */
	463
	464	s3c_rtc_tickno = platform_get_irq(pdev, 1);
	465	if (s3c_rtc_tickno < 0) {
	466	dev_err(&pdev->dev, "no irq for rtc tick\n");
	467	return -ENOENT;
	468	}
	469
	470	s3c_rtc_alarmno = platform_get_irq(pdev, 0);
	471	if (s3c_rtc_alarmno < 0) {
	472	dev_err(&pdev->dev, "no irq for alarm\n");
	473	return -ENOENT;
	474	}
	475
	476	pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
	477	s3c_rtc_tickno, s3c_rtc_alarmno);
	478
	479	/* get the memory region */
	480
	481	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	482	if (res == NULL) {
	483	dev_err(&pdev->dev, "failed to get memory region resource\n");
	484	return -ENOENT;
	485	}
	486
	487	s3c_rtc_mem = request_mem_region(res->start,
9a654518 BD	488	res->end-res->start+1,
9a654518 BD	489	pdev->name);
1add6781 BD	490
	491	if (s3c_rtc_mem == NULL) {
	492	dev_err(&pdev->dev, "failed to reserve memory region\n");
	493	ret = -ENOENT;
	494	goto err_nores;
	495	}
	496
	497	s3c_rtc_base = ioremap(res->start, res->end - res->start + 1);
	498	if (s3c_rtc_base == NULL) {
	499	dev_err(&pdev->dev, "failed ioremap()\n");
	500	ret = -EINVAL;
	501	goto err_nomap;
	502	}
	503
	504	/* check to see if everything is setup correctly */
	505
	506	s3c_rtc_enable(pdev, 1);
	507
9a654518 BD	508	pr_debug("s3c2410_rtc: RTCCON=%02x\n",
9a654518 BD	509	readb(s3c_rtc_base + S3C2410_RTCCON));
1add6781 BD	510
	511	s3c_rtc_setfreq(s3c_rtc_freq);
	512
	513	/* register RTC and exit */
	514
	515	rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops,
	516	THIS_MODULE);
	517
	518	if (IS_ERR(rtc)) {
	519	dev_err(&pdev->dev, "cannot attach rtc\n");
	520	ret = PTR_ERR(rtc);
	521	goto err_nortc;
	522	}
	523
	524	rtc->max_user_freq = 128;
	525
	526	platform_set_drvdata(pdev, rtc);
	527	return 0;
	528
	529	err_nortc:
	530	s3c_rtc_enable(pdev, 0);
	531	iounmap(s3c_rtc_base);
	532
	533	err_nomap:
	534	release_resource(s3c_rtc_mem);
	535
	536	err_nores:
	537	return ret;
	538	}
	539
	540	#ifdef CONFIG_PM
	541
	542	/* RTC Power management control */
	543
1add6781 BD	544	static int ticnt_save;
	545
	546	static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
	547	{
1add6781	548	/* save TICNT for anyone using periodic interrupts */
9a654518	549	ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
1add6781	550	s3c_rtc_enable(pdev, 0);
1add6781 BD	551	return 0;
	552	}
	553
	554	static int s3c_rtc_resume(struct platform_device *pdev)
	555	{
1add6781	556	s3c_rtc_enable(pdev, 1);
9a654518	557	writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
1add6781 BD	558	return 0;
	559	}
	560	#else
	561	#define s3c_rtc_suspend NULL
	562	#define s3c_rtc_resume NULL
	563	#endif
	564
	565	static struct platform_driver s3c2410_rtcdrv = {
	566	.probe = s3c_rtc_probe,
	567	.remove = s3c_rtc_remove,
	568	.suspend = s3c_rtc_suspend,
	569	.resume = s3c_rtc_resume,
	570	.driver = {
	571	.name = "s3c2410-rtc",
	572	.owner = THIS_MODULE,
	573	},
	574	};
	575
	576	static char __initdata banner[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";
	577
	578	static int __init s3c_rtc_init(void)
	579	{
	580	printk(banner);
	581	return platform_driver_register(&s3c2410_rtcdrv);
	582	}
	583
	584	static void __exit s3c_rtc_exit(void)
	585	{
	586	platform_driver_unregister(&s3c2410_rtcdrv);
	587	}
	588
	589	module_init(s3c_rtc_init);
	590	module_exit(s3c_rtc_exit);
	591
	592	MODULE_DESCRIPTION("Samsung S3C RTC Driver");
	593	MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
	594	MODULE_LICENSE("GPL");
ad28a07b	595	MODULE_ALIAS("platform:s3c2410-rtc");