[linux-block.git] / drivers / rtc / rtc-s3c.c

/* drivers/rtc/rtc-s3c.c
 *
 * Copyright (c) 2010 Samsung Electronics Co., Ltd.
 *		http://www.samsung.com/
 *
 * 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 <linux/slab.h>

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

enum s3c_cpu_type {
	TYPE_S3C2410,
	TYPE_S3C64XX,
};

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

static struct resource *s3c_rtc_mem;

static struct clk *rtc_clk;
static void __iomem *s3c_rtc_base;
static int s3c_rtc_alarmno = NO_IRQ;
static int s3c_rtc_tickno  = NO_IRQ;
static enum s3c_cpu_type s3c_rtc_cpu_type;

static DEFINE_SPINLOCK(s3c_rtc_pie_lock);

/* IRQ Handlers */

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

	rtc_update_irq(rdev, 1, RTC_AF | RTC_IRQF);

	if (s3c_rtc_cpu_type == TYPE_S3C64XX)
		writeb(S3C2410_INTP_ALM, s3c_rtc_base + S3C2410_INTP);

	return IRQ_HANDLED;
}

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

	rtc_update_irq(rdev, 1, RTC_PF | RTC_IRQF);

	if (s3c_rtc_cpu_type == TYPE_S3C64XX)
		writeb(S3C2410_INTP_TIC, s3c_rtc_base + S3C2410_INTP);

	return IRQ_HANDLED;
}

/* Update control registers */
static int s3c_rtc_setaie(struct device *dev, unsigned int enabled)
{
	unsigned int tmp;

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

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

	if (enabled)
		tmp |= S3C2410_RTCALM_ALMEN;

	writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);

	return 0;
}

static int s3c_rtc_setfreq(struct device *dev, int freq)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
	unsigned int tmp = 0;

	if (!is_power_of_2(freq))
		return -EINVAL;

	spin_lock_irq(&s3c_rtc_pie_lock);

	if (s3c_rtc_cpu_type == TYPE_S3C2410) {
		tmp = readb(s3c_rtc_base + S3C2410_TICNT);
		tmp &= S3C2410_TICNT_ENABLE;
	}

	tmp |= (rtc_dev->max_user_freq / freq)-1;

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

	return 0;
}

/* Time read/write */

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

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

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

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

	pr_debug("read time %04d.%02d.%02d %02d:%02d:%02d\n",
		 1900 + rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
		 rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);

	rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
	rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
	rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
	rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
	rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
	rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);

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

	return rtc_valid_tm(rtc_tm);
}

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 %04d.%02d.%02d %02d:%02d:%02d\n",
		 1900 + 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 %d, %04d.%02d.%02d %02d:%02d:%02d\n",
		 alm_en,
		 1900 + 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)
		alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
	else
		alm_tm->tm_sec = -1;

	if (alm_en & S3C2410_RTCALM_MINEN)
		alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
	else
		alm_tm->tm_min = -1;

	if (alm_en & S3C2410_RTCALM_HOUREN)
		alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
	else
		alm_tm->tm_hour = -1;

	if (alm_en & S3C2410_RTCALM_DAYEN)
		alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
	else
		alm_tm->tm_mday = -1;

	if (alm_en & S3C2410_RTCALM_MONEN) {
		alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
		alm_tm->tm_mon -= 1;
	} else {
		alm_tm->tm_mon = -1;
	}

	if (alm_en & S3C2410_RTCALM_YEAREN)
		alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
	else
		alm_tm->tm_year = -1;

	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, %04d.%02d.%02d %02d:%02d:%02d\n",
		 alrm->enabled,
		 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
		 tm->tm_hour, tm->tm_min, tm->tm_sec);


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

	if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
		alrm_en |= S3C2410_RTCALM_SECEN;
		writeb(bin2bcd(tm->tm_sec), base + S3C2410_ALMSEC);
	}

	if (tm->tm_min < 60 && tm->tm_min >= 0) {
		alrm_en |= S3C2410_RTCALM_MINEN;
		writeb(bin2bcd(tm->tm_min), base + S3C2410_ALMMIN);
	}

	if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
		alrm_en |= S3C2410_RTCALM_HOUREN;
		writeb(bin2bcd(tm->tm_hour), base + S3C2410_ALMHOUR);
	}

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

	writeb(alrm_en, base + S3C2410_RTCALM);

	s3c_rtc_setaie(dev, alrm->enabled);

	return 0;
}

static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
{
	unsigned int ticnt;

	if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
		ticnt = readw(s3c_rtc_base + S3C2410_RTCCON);
		ticnt &= S3C64XX_RTCCON_TICEN;
	} else {
		ticnt = readb(s3c_rtc_base + S3C2410_TICNT);
		ticnt &= S3C2410_TICNT_ENABLE;
	}

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

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

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

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

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

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

	return ret;

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

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

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

	free_irq(s3c_rtc_alarmno, rtc_dev);
	free_irq(s3c_rtc_tickno, rtc_dev);
}

static const struct rtc_class_ops s3c_rtcops = {
	.open		= s3c_rtc_open,
	.release	= s3c_rtc_release,
	.read_time	= s3c_rtc_gettime,
	.set_time	= s3c_rtc_settime,
	.read_alarm	= s3c_rtc_getalarm,
	.set_alarm	= s3c_rtc_setalarm,
	.proc		= s3c_rtc_proc,
	.alarm_irq_enable = s3c_rtc_setaie,
};

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 = readw(base + S3C2410_RTCCON);
		if (s3c_rtc_cpu_type == TYPE_S3C64XX)
			tmp &= ~S3C64XX_RTCCON_TICEN;
		tmp &= ~S3C2410_RTCCON_RTCEN;
		writew(tmp, base + S3C2410_RTCCON);

		if (s3c_rtc_cpu_type == TYPE_S3C2410) {
			tmp = readb(base + S3C2410_TICNT);
			tmp &= ~S3C2410_TICNT_ENABLE;
			writeb(tmp, base + S3C2410_TICNT);
		}
	} else {
		/* re-enable the device, and check it is ok */

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

			tmp = readw(base + S3C2410_RTCCON);
			writew(tmp | S3C2410_RTCCON_RTCEN,
				base + S3C2410_RTCCON);
		}

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

			tmp = readw(base + S3C2410_RTCCON);
			writew(tmp & ~S3C2410_RTCCON_CNTSEL,
				base + S3C2410_RTCCON);
		}

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

			tmp = readw(base + S3C2410_RTCCON);
			writew(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_setaie(&dev->dev, 0);

	clk_disable(rtc_clk);
	clk_put(rtc_clk);
	rtc_clk = NULL;

	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 rtc_time rtc_tm;
	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;
	}

	rtc_clk = clk_get(&pdev->dev, "rtc");
	if (IS_ERR(rtc_clk)) {
		dev_err(&pdev->dev, "failed to find rtc clock source\n");
		ret = PTR_ERR(rtc_clk);
		rtc_clk = NULL;
		goto err_clk;
	}

	clk_enable(rtc_clk);

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

	s3c_rtc_enable(pdev, 1);

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

	device_init_wakeup(&pdev->dev, 1);

	/* register RTC and exit */

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

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

	s3c_rtc_cpu_type = platform_get_device_id(pdev)->driver_data;

	/* Check RTC Time */

	s3c_rtc_gettime(NULL, &rtc_tm);

	if (rtc_valid_tm(&rtc_tm)) {
		rtc_tm.tm_year	= 100;
		rtc_tm.tm_mon	= 0;
		rtc_tm.tm_mday	= 1;
		rtc_tm.tm_hour	= 0;
		rtc_tm.tm_min	= 0;
		rtc_tm.tm_sec	= 0;

		s3c_rtc_settime(NULL, &rtc_tm);

		dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n");
	}

	if (s3c_rtc_cpu_type == TYPE_S3C64XX)
		rtc->max_user_freq = 32768;
	else
		rtc->max_user_freq = 128;

	platform_set_drvdata(pdev, rtc);

	s3c_rtc_setfreq(&pdev->dev, 1);

	return 0;

 err_nortc:
	s3c_rtc_enable(pdev, 0);
	clk_disable(rtc_clk);
	clk_put(rtc_clk);

 err_clk:
	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, ticnt_en_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);
	if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
		ticnt_en_save = readw(s3c_rtc_base + S3C2410_RTCCON);
		ticnt_en_save &= S3C64XX_RTCCON_TICEN;
	}
	s3c_rtc_enable(pdev, 0);

	if (device_may_wakeup(&pdev->dev))
		enable_irq_wake(s3c_rtc_alarmno);

	return 0;
}

static int s3c_rtc_resume(struct platform_device *pdev)
{
	unsigned int tmp;

	s3c_rtc_enable(pdev, 1);
	writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
	if (s3c_rtc_cpu_type == TYPE_S3C64XX && ticnt_en_save) {
		tmp = readw(s3c_rtc_base + S3C2410_RTCCON);
		writew(tmp | ticnt_en_save, s3c_rtc_base + S3C2410_RTCCON);
	}

	if (device_may_wakeup(&pdev->dev))
		disable_irq_wake(s3c_rtc_alarmno);

	return 0;
}
#else
#define s3c_rtc_suspend NULL
#define s3c_rtc_resume  NULL
#endif

static struct platform_device_id s3c_rtc_driver_ids[] = {
	{
		.name		= "s3c2410-rtc",
		.driver_data	= TYPE_S3C2410,
	}, {
		.name		= "s3c64xx-rtc",
		.driver_data	= TYPE_S3C64XX,
	},
	{ }
};

MODULE_DEVICE_TABLE(platform, s3c_rtc_driver_ids);

static struct platform_driver s3c_rtc_driver = {
	.probe		= s3c_rtc_probe,
	.remove		= __devexit_p(s3c_rtc_remove),
	.suspend	= s3c_rtc_suspend,
	.resume		= s3c_rtc_resume,
	.id_table	= s3c_rtc_driver_ids,
	.driver		= {
		.name	= "s3c-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(&s3c_rtc_driver);
}

static void __exit s3c_rtc_exit(void)
{
	platform_driver_unregister(&s3c_rtc_driver);
}

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
	1	/* drivers/rtc/rtc-s3c.c
	2	*
	3	* Copyright (c) 2010 Samsung Electronics Co., Ltd.
	4	* http://www.samsung.com/
	5	*
	6	* Copyright (c) 2004,2006 Simtec Electronics
	7	* Ben Dooks, <ben@simtec.co.uk>
	8	* http://armlinux.simtec.co.uk/
	9	*
	10	* This program is free software; you can redistribute it and/or modify
	11	* it under the terms of the GNU General Public License version 2 as
	12	* published by the Free Software Foundation.
	13	*
	14	* S3C2410/S3C2440/S3C24XX Internal RTC Driver
	15	*/
	16
	17	#include <linux/module.h>
	18	#include <linux/fs.h>
	19	#include <linux/string.h>
	20	#include <linux/init.h>
	21	#include <linux/platform_device.h>
	22	#include <linux/interrupt.h>
	23	#include <linux/rtc.h>
	24	#include <linux/bcd.h>
	25	#include <linux/clk.h>
	26	#include <linux/log2.h>
	27	#include <linux/slab.h>
	28
	29	#include <mach/hardware.h>
	30	#include <asm/uaccess.h>
	31	#include <asm/io.h>
	32	#include <asm/irq.h>
	33	#include <plat/regs-rtc.h>
	34
	35	enum s3c_cpu_type {
	36	TYPE_S3C2410,
	37	TYPE_S3C64XX,
	38	};
	39
	40	/* I have yet to find an S3C implementation with more than one
	41	* of these rtc blocks in */
	42
	43	static struct resource *s3c_rtc_mem;
	44
	45	static struct clk *rtc_clk;
	46	static void __iomem *s3c_rtc_base;
	47	static int s3c_rtc_alarmno = NO_IRQ;
	48	static int s3c_rtc_tickno = NO_IRQ;
	49	static enum s3c_cpu_type s3c_rtc_cpu_type;
	50
	51	static DEFINE_SPINLOCK(s3c_rtc_pie_lock);
	52
	53	/* IRQ Handlers */
	54
	55	static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
	56	{
	57	struct rtc_device *rdev = id;
	58
	59	rtc_update_irq(rdev, 1, RTC_AF \| RTC_IRQF);
	60
	61	if (s3c_rtc_cpu_type == TYPE_S3C64XX)
	62	writeb(S3C2410_INTP_ALM, s3c_rtc_base + S3C2410_INTP);
	63
	64	return IRQ_HANDLED;
	65	}
	66
	67	static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
	68	{
	69	struct rtc_device *rdev = id;
	70
	71	rtc_update_irq(rdev, 1, RTC_PF \| RTC_IRQF);
	72
	73	if (s3c_rtc_cpu_type == TYPE_S3C64XX)
	74	writeb(S3C2410_INTP_TIC, s3c_rtc_base + S3C2410_INTP);
	75
	76	return IRQ_HANDLED;
	77	}
	78
	79	/* Update control registers */
	80	static int s3c_rtc_setaie(struct device *dev, unsigned int enabled)
	81	{
	82	unsigned int tmp;
	83
	84	pr_debug("%s: aie=%d\n", __func__, enabled);
	85
	86	tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
	87
	88	if (enabled)
	89	tmp \|= S3C2410_RTCALM_ALMEN;
	90
	91	writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
	92
	93	return 0;
	94	}
	95
	96	static int s3c_rtc_setfreq(struct device *dev, int freq)
	97	{
	98	struct platform_device *pdev = to_platform_device(dev);
	99	struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
	100	unsigned int tmp = 0;
	101
	102	if (!is_power_of_2(freq))
	103	return -EINVAL;
	104
	105	spin_lock_irq(&s3c_rtc_pie_lock);
	106
	107	if (s3c_rtc_cpu_type == TYPE_S3C2410) {
	108	tmp = readb(s3c_rtc_base + S3C2410_TICNT);
	109	tmp &= S3C2410_TICNT_ENABLE;
	110	}
	111
	112	tmp \|= (rtc_dev->max_user_freq / freq)-1;
	113
	114	writel(tmp, s3c_rtc_base + S3C2410_TICNT);
	115	spin_unlock_irq(&s3c_rtc_pie_lock);
	116
	117	return 0;
	118	}
	119
	120	/* Time read/write */
	121
	122	static int s3c_rtc_gettime(struct device dev, struct rtc_time rtc_tm)
	123	{
	124	unsigned int have_retried = 0;
	125	void __iomem *base = s3c_rtc_base;
	126
	127	retry_get_time:
	128	rtc_tm->tm_min = readb(base + S3C2410_RTCMIN);
	129	rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR);
	130	rtc_tm->tm_mday = readb(base + S3C2410_RTCDATE);
	131	rtc_tm->tm_mon = readb(base + S3C2410_RTCMON);
	132	rtc_tm->tm_year = readb(base + S3C2410_RTCYEAR);
	133	rtc_tm->tm_sec = readb(base + S3C2410_RTCSEC);
	134
	135	/* the only way to work out wether the system was mid-update
	136	* when we read it is to check the second counter, and if it
	137	* is zero, then we re-try the entire read
	138	*/
	139
	140	if (rtc_tm->tm_sec == 0 && !have_retried) {
	141	have_retried = 1;
	142	goto retry_get_time;
	143	}
	144
	145	pr_debug("read time %04d.%02d.%02d %02d:%02d:%02d\n",
	146	1900 + rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
	147	rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
	148
	149	rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
	150	rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
	151	rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
	152	rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
	153	rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
	154	rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
	155
	156	rtc_tm->tm_year += 100;
	157	rtc_tm->tm_mon -= 1;
	158
	159	return rtc_valid_tm(rtc_tm);
	160	}
	161
	162	static int s3c_rtc_settime(struct device dev, struct rtc_time tm)
	163	{
	164	void __iomem *base = s3c_rtc_base;
	165	int year = tm->tm_year - 100;
	166
	167	pr_debug("set time %04d.%02d.%02d %02d:%02d:%02d\n",
	168	1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
	169	tm->tm_hour, tm->tm_min, tm->tm_sec);
	170
	171	/* we get around y2k by simply not supporting it */
	172
	173	if (year < 0 \|\| year >= 100) {
	174	dev_err(dev, "rtc only supports 100 years\n");
	175	return -EINVAL;
	176	}
	177
	178	writeb(bin2bcd(tm->tm_sec), base + S3C2410_RTCSEC);
	179	writeb(bin2bcd(tm->tm_min), base + S3C2410_RTCMIN);
	180	writeb(bin2bcd(tm->tm_hour), base + S3C2410_RTCHOUR);
	181	writeb(bin2bcd(tm->tm_mday), base + S3C2410_RTCDATE);
	182	writeb(bin2bcd(tm->tm_mon + 1), base + S3C2410_RTCMON);
	183	writeb(bin2bcd(year), base + S3C2410_RTCYEAR);
	184
	185	return 0;
	186	}
	187
	188	static int s3c_rtc_getalarm(struct device dev, struct rtc_wkalrm alrm)
	189	{
	190	struct rtc_time *alm_tm = &alrm->time;
	191	void __iomem *base = s3c_rtc_base;
	192	unsigned int alm_en;
	193
	194	alm_tm->tm_sec = readb(base + S3C2410_ALMSEC);
	195	alm_tm->tm_min = readb(base + S3C2410_ALMMIN);
	196	alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR);
	197	alm_tm->tm_mon = readb(base + S3C2410_ALMMON);
	198	alm_tm->tm_mday = readb(base + S3C2410_ALMDATE);
	199	alm_tm->tm_year = readb(base + S3C2410_ALMYEAR);
	200
	201	alm_en = readb(base + S3C2410_RTCALM);
	202
	203	alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
	204
	205	pr_debug("read alarm %d, %04d.%02d.%02d %02d:%02d:%02d\n",
	206	alm_en,
	207	1900 + alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
	208	alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
	209
	210
	211	/* decode the alarm enable field */
	212
	213	if (alm_en & S3C2410_RTCALM_SECEN)
	214	alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
	215	else
	216	alm_tm->tm_sec = -1;
	217
	218	if (alm_en & S3C2410_RTCALM_MINEN)
	219	alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
	220	else
	221	alm_tm->tm_min = -1;
	222
	223	if (alm_en & S3C2410_RTCALM_HOUREN)
	224	alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
	225	else
	226	alm_tm->tm_hour = -1;
	227
	228	if (alm_en & S3C2410_RTCALM_DAYEN)
	229	alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
	230	else
	231	alm_tm->tm_mday = -1;
	232
	233	if (alm_en & S3C2410_RTCALM_MONEN) {
	234	alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
	235	alm_tm->tm_mon -= 1;
	236	} else {
	237	alm_tm->tm_mon = -1;
	238	}
	239
	240	if (alm_en & S3C2410_RTCALM_YEAREN)
	241	alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
	242	else
	243	alm_tm->tm_year = -1;
	244
	245	return 0;
	246	}
	247
	248	static int s3c_rtc_setalarm(struct device dev, struct rtc_wkalrm alrm)
	249	{
	250	struct rtc_time *tm = &alrm->time;
	251	void __iomem *base = s3c_rtc_base;
	252	unsigned int alrm_en;
	253
	254	pr_debug("s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n",
	255	alrm->enabled,
	256	1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
	257	tm->tm_hour, tm->tm_min, tm->tm_sec);
	258
	259
	260	alrm_en = readb(base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
	261	writeb(0x00, base + S3C2410_RTCALM);
	262
	263	if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
	264	alrm_en \|= S3C2410_RTCALM_SECEN;
	265	writeb(bin2bcd(tm->tm_sec), base + S3C2410_ALMSEC);
	266	}
	267
	268	if (tm->tm_min < 60 && tm->tm_min >= 0) {
	269	alrm_en \|= S3C2410_RTCALM_MINEN;
	270	writeb(bin2bcd(tm->tm_min), base + S3C2410_ALMMIN);
	271	}
	272
	273	if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
	274	alrm_en \|= S3C2410_RTCALM_HOUREN;
	275	writeb(bin2bcd(tm->tm_hour), base + S3C2410_ALMHOUR);
	276	}
	277
	278	pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en);
	279
	280	writeb(alrm_en, base + S3C2410_RTCALM);
	281
	282	s3c_rtc_setaie(dev, alrm->enabled);
	283
	284	return 0;
	285	}
	286
	287	static int s3c_rtc_proc(struct device dev, struct seq_file seq)
	288	{
	289	unsigned int ticnt;
	290
	291	if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
	292	ticnt = readw(s3c_rtc_base + S3C2410_RTCCON);
	293	ticnt &= S3C64XX_RTCCON_TICEN;
	294	} else {
	295	ticnt = readb(s3c_rtc_base + S3C2410_TICNT);
	296	ticnt &= S3C2410_TICNT_ENABLE;
	297	}
	298
	299	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt ? "yes" : "no");
	300	return 0;
	301	}
	302
	303	static int s3c_rtc_open(struct device *dev)
	304	{
	305	struct platform_device *pdev = to_platform_device(dev);
	306	struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
	307	int ret;
	308
	309	ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq,
	310	IRQF_DISABLED, "s3c2410-rtc alarm", rtc_dev);
	311
	312	if (ret) {
	313	dev_err(dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret);
	314	return ret;
	315	}
	316
	317	ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq,
	318	IRQF_DISABLED, "s3c2410-rtc tick", rtc_dev);
	319
	320	if (ret) {
	321	dev_err(dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret);
	322	goto tick_err;
	323	}
	324
	325	return ret;
	326
	327	tick_err:
	328	free_irq(s3c_rtc_alarmno, rtc_dev);
	329	return ret;
	330	}
	331
	332	static void s3c_rtc_release(struct device *dev)
	333	{
	334	struct platform_device *pdev = to_platform_device(dev);
	335	struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
	336
	337	/* do not clear AIE here, it may be needed for wake */
	338
	339	free_irq(s3c_rtc_alarmno, rtc_dev);
	340	free_irq(s3c_rtc_tickno, rtc_dev);
	341	}
	342
	343	static const struct rtc_class_ops s3c_rtcops = {
	344	.open = s3c_rtc_open,
	345	.release = s3c_rtc_release,
	346	.read_time = s3c_rtc_gettime,
	347	.set_time = s3c_rtc_settime,
	348	.read_alarm = s3c_rtc_getalarm,
	349	.set_alarm = s3c_rtc_setalarm,
	350	.proc = s3c_rtc_proc,
	351	.alarm_irq_enable = s3c_rtc_setaie,
	352	};
	353
	354	static void s3c_rtc_enable(struct platform_device *pdev, int en)
	355	{
	356	void __iomem *base = s3c_rtc_base;
	357	unsigned int tmp;
	358
	359	if (s3c_rtc_base == NULL)
	360	return;
	361
	362	if (!en) {
	363	tmp = readw(base + S3C2410_RTCCON);
	364	if (s3c_rtc_cpu_type == TYPE_S3C64XX)
	365	tmp &= ~S3C64XX_RTCCON_TICEN;
	366	tmp &= ~S3C2410_RTCCON_RTCEN;
	367	writew(tmp, base + S3C2410_RTCCON);
	368
	369	if (s3c_rtc_cpu_type == TYPE_S3C2410) {
	370	tmp = readb(base + S3C2410_TICNT);
	371	tmp &= ~S3C2410_TICNT_ENABLE;
	372	writeb(tmp, base + S3C2410_TICNT);
	373	}
	374	} else {
	375	/* re-enable the device, and check it is ok */
	376
	377	if ((readw(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0) {
	378	dev_info(&pdev->dev, "rtc disabled, re-enabling\n");
	379
	380	tmp = readw(base + S3C2410_RTCCON);
	381	writew(tmp \| S3C2410_RTCCON_RTCEN,
	382	base + S3C2410_RTCCON);
	383	}
	384
	385	if ((readw(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)) {
	386	dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n");
	387
	388	tmp = readw(base + S3C2410_RTCCON);
	389	writew(tmp & ~S3C2410_RTCCON_CNTSEL,
	390	base + S3C2410_RTCCON);
	391	}
	392
	393	if ((readw(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)) {
	394	dev_info(&pdev->dev, "removing RTCCON_CLKRST\n");
	395
	396	tmp = readw(base + S3C2410_RTCCON);
	397	writew(tmp & ~S3C2410_RTCCON_CLKRST,
	398	base + S3C2410_RTCCON);
	399	}
	400	}
	401	}
	402
	403	static int __devexit s3c_rtc_remove(struct platform_device *dev)
	404	{
	405	struct rtc_device *rtc = platform_get_drvdata(dev);
	406
	407	platform_set_drvdata(dev, NULL);
	408	rtc_device_unregister(rtc);
	409
	410	s3c_rtc_setaie(&dev->dev, 0);
	411
	412	clk_disable(rtc_clk);
	413	clk_put(rtc_clk);
	414	rtc_clk = NULL;
	415
	416	iounmap(s3c_rtc_base);
	417	release_resource(s3c_rtc_mem);
	418	kfree(s3c_rtc_mem);
	419
	420	return 0;
	421	}
	422
	423	static int __devinit s3c_rtc_probe(struct platform_device *pdev)
	424	{
	425	struct rtc_device *rtc;
	426	struct rtc_time rtc_tm;
	427	struct resource *res;
	428	int ret;
	429
	430	pr_debug("%s: probe=%p\n", __func__, pdev);
	431
	432	/* find the IRQs */
	433
	434	s3c_rtc_tickno = platform_get_irq(pdev, 1);
	435	if (s3c_rtc_tickno < 0) {
	436	dev_err(&pdev->dev, "no irq for rtc tick\n");
	437	return -ENOENT;
	438	}
	439
	440	s3c_rtc_alarmno = platform_get_irq(pdev, 0);
	441	if (s3c_rtc_alarmno < 0) {
	442	dev_err(&pdev->dev, "no irq for alarm\n");
	443	return -ENOENT;
	444	}
	445
	446	pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
	447	s3c_rtc_tickno, s3c_rtc_alarmno);
	448
	449	/* get the memory region */
	450
	451	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	452	if (res == NULL) {
	453	dev_err(&pdev->dev, "failed to get memory region resource\n");
	454	return -ENOENT;
	455	}
	456
	457	s3c_rtc_mem = request_mem_region(res->start,
	458	res->end-res->start+1,
	459	pdev->name);
	460
	461	if (s3c_rtc_mem == NULL) {
	462	dev_err(&pdev->dev, "failed to reserve memory region\n");
	463	ret = -ENOENT;
	464	goto err_nores;
	465	}
	466
	467	s3c_rtc_base = ioremap(res->start, res->end - res->start + 1);
	468	if (s3c_rtc_base == NULL) {
	469	dev_err(&pdev->dev, "failed ioremap()\n");
	470	ret = -EINVAL;
	471	goto err_nomap;
	472	}
	473
	474	rtc_clk = clk_get(&pdev->dev, "rtc");
	475	if (IS_ERR(rtc_clk)) {
	476	dev_err(&pdev->dev, "failed to find rtc clock source\n");
	477	ret = PTR_ERR(rtc_clk);
	478	rtc_clk = NULL;
	479	goto err_clk;
	480	}
	481
	482	clk_enable(rtc_clk);
	483
	484	/* check to see if everything is setup correctly */
	485
	486	s3c_rtc_enable(pdev, 1);
	487
	488	pr_debug("s3c2410_rtc: RTCCON=%02x\n",
	489	readw(s3c_rtc_base + S3C2410_RTCCON));
	490
	491	device_init_wakeup(&pdev->dev, 1);
	492
	493	/* register RTC and exit */
	494
	495	rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops,
	496	THIS_MODULE);
	497
	498	if (IS_ERR(rtc)) {
	499	dev_err(&pdev->dev, "cannot attach rtc\n");
	500	ret = PTR_ERR(rtc);
	501	goto err_nortc;
	502	}
	503
	504	s3c_rtc_cpu_type = platform_get_device_id(pdev)->driver_data;
	505
	506	/* Check RTC Time */
	507
	508	s3c_rtc_gettime(NULL, &rtc_tm);
	509
	510	if (rtc_valid_tm(&rtc_tm)) {
	511	rtc_tm.tm_year = 100;
	512	rtc_tm.tm_mon = 0;
	513	rtc_tm.tm_mday = 1;
	514	rtc_tm.tm_hour = 0;
	515	rtc_tm.tm_min = 0;
	516	rtc_tm.tm_sec = 0;
	517
	518	s3c_rtc_settime(NULL, &rtc_tm);
	519
	520	dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n");
	521	}
	522
	523	if (s3c_rtc_cpu_type == TYPE_S3C64XX)
	524	rtc->max_user_freq = 32768;
	525	else
	526	rtc->max_user_freq = 128;
	527
	528	platform_set_drvdata(pdev, rtc);
	529
	530	s3c_rtc_setfreq(&pdev->dev, 1);
	531
	532	return 0;
	533
	534	err_nortc:
	535	s3c_rtc_enable(pdev, 0);
	536	clk_disable(rtc_clk);
	537	clk_put(rtc_clk);
	538
	539	err_clk:
	540	iounmap(s3c_rtc_base);
	541
	542	err_nomap:
	543	release_resource(s3c_rtc_mem);
	544
	545	err_nores:
	546	return ret;
	547	}
	548
	549	#ifdef CONFIG_PM
	550
	551	/* RTC Power management control */
	552
	553	static int ticnt_save, ticnt_en_save;
	554
	555	static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
	556	{
	557	/* save TICNT for anyone using periodic interrupts */
	558	ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
	559	if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
	560	ticnt_en_save = readw(s3c_rtc_base + S3C2410_RTCCON);
	561	ticnt_en_save &= S3C64XX_RTCCON_TICEN;
	562	}
	563	s3c_rtc_enable(pdev, 0);
	564
	565	if (device_may_wakeup(&pdev->dev))
	566	enable_irq_wake(s3c_rtc_alarmno);
	567
	568	return 0;
	569	}
	570
	571	static int s3c_rtc_resume(struct platform_device *pdev)
	572	{
	573	unsigned int tmp;
	574
	575	s3c_rtc_enable(pdev, 1);
	576	writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
	577	if (s3c_rtc_cpu_type == TYPE_S3C64XX && ticnt_en_save) {
	578	tmp = readw(s3c_rtc_base + S3C2410_RTCCON);
	579	writew(tmp \| ticnt_en_save, s3c_rtc_base + S3C2410_RTCCON);
	580	}
	581
	582	if (device_may_wakeup(&pdev->dev))
	583	disable_irq_wake(s3c_rtc_alarmno);
	584
	585	return 0;
	586	}
	587	#else
	588	#define s3c_rtc_suspend NULL
	589	#define s3c_rtc_resume NULL
	590	#endif
	591
	592	static struct platform_device_id s3c_rtc_driver_ids[] = {
	593	{
	594	.name = "s3c2410-rtc",
	595	.driver_data = TYPE_S3C2410,
	596	}, {
	597	.name = "s3c64xx-rtc",
	598	.driver_data = TYPE_S3C64XX,
	599	},
	600	{ }
	601	};
	602
	603	MODULE_DEVICE_TABLE(platform, s3c_rtc_driver_ids);
	604
	605	static struct platform_driver s3c_rtc_driver = {
	606	.probe = s3c_rtc_probe,
	607	.remove = __devexit_p(s3c_rtc_remove),
	608	.suspend = s3c_rtc_suspend,
	609	.resume = s3c_rtc_resume,
	610	.id_table = s3c_rtc_driver_ids,
	611	.driver = {
	612	.name = "s3c-rtc",
	613	.owner = THIS_MODULE,
	614	},
	615	};
	616
	617	static char __initdata banner[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";
	618
	619	static int __init s3c_rtc_init(void)
	620	{
	621	printk(banner);
	622	return platform_driver_register(&s3c_rtc_driver);
	623	}
	624
	625	static void __exit s3c_rtc_exit(void)
	626	{
	627	platform_driver_unregister(&s3c_rtc_driver);
	628	}
	629
	630	module_init(s3c_rtc_init);
	631	module_exit(s3c_rtc_exit);
	632
	633	MODULE_DESCRIPTION("Samsung S3C RTC Driver");
	634	MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
	635	MODULE_LICENSE("GPL");
	636	MODULE_ALIAS("platform:s3c2410-rtc");