1 files changed, 369 insertions, 267 deletions

diff --git a/drivers/rtc/rtc-s3c.c b/drivers/rtc/rtc-s3c.c
index 86766f1f249..4958a363b2c 100644
--- a/drivers/rtc/rtc-s3c.c
+++ b/drivers/rtc/rtc-s3c.c
@@ -1,5 +1,8 @@
 /* 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/
@@ -21,29 +24,56 @@
 #include <linux/bcd.h>
 #include <linux/clk.h>
 #include <linux/log2.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
 
-#include <asm/hardware.h>
-#include <asm/uaccess.h>
-#include <asm/io.h>
 #include <asm/irq.h>
-#include <asm/rtc.h>
+#include "rtc-s3c.h"
 
-#include <asm/mach/time.h>
+enum s3c_cpu_type {
+	TYPE_S3C2410,
+	TYPE_S3C2416,
+	TYPE_S3C2443,
+	TYPE_S3C64XX,
+};
 
-#include <asm/plat-s3c/regs-rtc.h>
+struct s3c_rtc_drv_data {
+	int cpu_type;
+};
 
 /* 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 int s3c_rtc_freq    = 1;
+static int s3c_rtc_alarmno;
+static int s3c_rtc_tickno;
+static enum s3c_cpu_type s3c_rtc_cpu_type;
 
 static DEFINE_SPINLOCK(s3c_rtc_pie_lock);
-static unsigned int tick_count;
+
+static void s3c_rtc_alarm_clk_enable(bool enable)
+{
+	static DEFINE_SPINLOCK(s3c_rtc_alarm_clk_lock);
+	static bool alarm_clk_enabled;
+	unsigned long irq_flags;
+
+	spin_lock_irqsave(&s3c_rtc_alarm_clk_lock, irq_flags);
+	if (enable) {
+		if (!alarm_clk_enabled) {
+			clk_enable(rtc_clk);
+			alarm_clk_enabled = true;
+		}
+	} else {
+		if (alarm_clk_enabled) {
+			clk_disable(rtc_clk);
+			alarm_clk_enabled = false;
+		}
+	}
+	spin_unlock_irqrestore(&s3c_rtc_alarm_clk_lock, irq_flags);
+}
 
 /* IRQ Handlers */
 
@@ -51,7 +81,16 @@ static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
 {
 	struct rtc_device *rdev = id;
 
+	clk_enable(rtc_clk);
 	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);
+
+	clk_disable(rtc_clk);
+
+	s3c_rtc_alarm_clk_enable(false);
+
 	return IRQ_HANDLED;
 }
 
@@ -59,54 +98,72 @@ 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);
+	clk_enable(rtc_clk);
+	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);
+
+	clk_disable(rtc_clk);
 	return IRQ_HANDLED;
 }
 
 /* Update control registers */
-static void s3c_rtc_setaie(int to)
+static int s3c_rtc_setaie(struct device *dev, unsigned int enabled)
 {
 	unsigned int tmp;
 
-	pr_debug("%s: aie=%d\n", __FUNCTION__, to);
+	dev_dbg(dev, "%s: aie=%d\n", __func__, enabled);
 
+	clk_enable(rtc_clk);
 	tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
 
-	if (to)
+	if (enabled)
 		tmp |= S3C2410_RTCALM_ALMEN;
 
 	writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
+	clk_disable(rtc_clk);
+
+	s3c_rtc_alarm_clk_enable(enabled);
+
+	return 0;
 }
 
-static void s3c_rtc_setpie(int to)
+static int s3c_rtc_setfreq(struct device *dev, int freq)
 {
-	unsigned int tmp;
+	struct platform_device *pdev = to_platform_device(dev);
+	struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
+	unsigned int tmp = 0;
+	int val;
 
-	pr_debug("%s: pie=%d\n", __FUNCTION__, to);
+	if (!is_power_of_2(freq))
+		return -EINVAL;
 
+	clk_enable(rtc_clk);
 	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;
+	if (s3c_rtc_cpu_type != TYPE_S3C64XX) {
+		tmp = readb(s3c_rtc_base + S3C2410_TICNT);
+		tmp &= S3C2410_TICNT_ENABLE;
+	}
 
-	spin_lock_irq(&s3c_rtc_pie_lock);
-	tmp = readb(s3c_rtc_base + S3C2410_TICNT) & S3C2410_TICNT_ENABLE;
+	val = (rtc_dev->max_user_freq / freq) - 1;
 
-	s3c_rtc_freq = freq;
+	if (s3c_rtc_cpu_type == TYPE_S3C2416 || s3c_rtc_cpu_type == TYPE_S3C2443) {
+		tmp |= S3C2443_TICNT_PART(val);
+		writel(S3C2443_TICNT1_PART(val), s3c_rtc_base + S3C2443_TICNT1);
 
-	tmp |= (128 / freq)-1;
+		if (s3c_rtc_cpu_type == TYPE_S3C2416)
+			writel(S3C2416_TICNT2_PART(val), s3c_rtc_base + S3C2416_TICNT2);
+	} else {
+		tmp |= val;
+	}
 
-	writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
+	writel(tmp, s3c_rtc_base + S3C2410_TICNT);
 	spin_unlock_irq(&s3c_rtc_pie_lock);
+	clk_disable(rtc_clk);
+
+	return 0;
 }
 
 /* Time read/write */
@@ -116,6 +173,7 @@ static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
 	unsigned int have_retried = 0;
 	void __iomem *base = s3c_rtc_base;
 
+	clk_enable(rtc_clk);
  retry_get_time:
 	rtc_tm->tm_min  = readb(base + S3C2410_RTCMIN);
 	rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR);
@@ -124,7 +182,7 @@ static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
 	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
+	/* the only way to work out whether 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
 	 */
@@ -134,21 +192,23 @@ static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
 		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_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;
+
+	dev_dbg(dev, "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_mon -= 1;
 
-	return 0;
+	clk_disable(rtc_clk);
+	return rtc_valid_tm(rtc_tm);
 }
 
 static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
@@ -156,8 +216,8 @@ 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,
+	dev_dbg(dev, "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 */
@@ -167,12 +227,14 @@ static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
 		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);
+	clk_enable(rtc_clk);
+	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);
+	clk_disable(rtc_clk);
 
 	return 0;
 }
@@ -183,6 +245,7 @@ static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
 	void __iomem *base = s3c_rtc_base;
 	unsigned int alm_en;
 
+	clk_enable(rtc_clk);
 	alm_tm->tm_sec  = readb(base + S3C2410_ALMSEC);
 	alm_tm->tm_min  = readb(base + S3C2410_ALMMIN);
 	alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR);
@@ -194,46 +257,47 @@ static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
 
 	alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
 
-	pr_debug("read alarm %02x %02x.%02x.%02x %02x/%02x/%02x\n",
+	dev_dbg(dev, "read alarm %d, %04d.%02d.%02d %02d:%02d:%02d\n",
 		 alm_en,
-		 alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
+		 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)
-		BCD_TO_BIN(alm_tm->tm_sec);
+		alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
 	else
-		alm_tm->tm_sec = 0xff;
+		alm_tm->tm_sec = -1;
 
 	if (alm_en & S3C2410_RTCALM_MINEN)
-		BCD_TO_BIN(alm_tm->tm_min);
+		alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
 	else
-		alm_tm->tm_min = 0xff;
+		alm_tm->tm_min = -1;
 
 	if (alm_en & S3C2410_RTCALM_HOUREN)
-		BCD_TO_BIN(alm_tm->tm_hour);
+		alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
 	else
-		alm_tm->tm_hour = 0xff;
+		alm_tm->tm_hour = -1;
 
 	if (alm_en & S3C2410_RTCALM_DAYEN)
-		BCD_TO_BIN(alm_tm->tm_mday);
+		alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
 	else
-		alm_tm->tm_mday = 0xff;
+		alm_tm->tm_mday = -1;
 
 	if (alm_en & S3C2410_RTCALM_MONEN) {
-		BCD_TO_BIN(alm_tm->tm_mon);
+		alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
 		alm_tm->tm_mon -= 1;
 	} else {
-		alm_tm->tm_mon = 0xff;
+		alm_tm->tm_mon = -1;
 	}
 
 	if (alm_en & S3C2410_RTCALM_YEAREN)
-		BCD_TO_BIN(alm_tm->tm_year);
+		alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
 	else
-		alm_tm->tm_year = 0xffff;
+		alm_tm->tm_year = -1;
 
+	clk_disable(rtc_clk);
 	return 0;
 }
 
@@ -243,155 +307,65 @@ static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
 	void __iomem *base = s3c_rtc_base;
 	unsigned int alrm_en;
 
-	pr_debug("s3c_rtc_setalarm: %d, %02x/%02x/%02x %02x.%02x.%02x\n",
+	clk_enable(rtc_clk);
+	dev_dbg(dev, "s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\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);
-
+		 1900 + tm->tm_year, tm->tm_mon + 1, 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);
+		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);
+		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);
+		writeb(bin2bcd(tm->tm_hour), base + S3C2410_ALMHOUR);
 	}
 
-	pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en);
+	dev_dbg(dev, "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);
+	s3c_rtc_setaie(dev, alrm->enabled);
 
+	clk_disable(rtc_clk);
 	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);
+	unsigned int ticnt;
 
-	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;
+	clk_enable(rtc_clk);
+	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;
 	}
 
-	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);
+	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
+	clk_disable(rtc_clk);
+	return 0;
 }
 
 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,
+	.proc		= s3c_rtc_proc,
+	.alarm_irq_enable = s3c_rtc_setaie,
 };
 
 static void s3c_rtc_enable(struct platform_device *pdev, int en)
@@ -402,117 +376,131 @@ static void s3c_rtc_enable(struct platform_device *pdev, int en)
 	if (s3c_rtc_base == NULL)
 		return;
 
+	clk_enable(rtc_clk);
 	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);
+		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_S3C64XX) {
+			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 ((readb(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0){
+		if ((readw(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);
+			tmp = readw(base + S3C2410_RTCCON);
+			writew(tmp | S3C2410_RTCCON_RTCEN,
+				base + S3C2410_RTCCON);
 		}
 
-		if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)){
+		if ((readw(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);
+			tmp = readw(base + S3C2410_RTCCON);
+			writew(tmp & ~S3C2410_RTCCON_CNTSEL,
+				base + S3C2410_RTCCON);
 		}
 
-		if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)){
+		if ((readw(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);
+			tmp = readw(base + S3C2410_RTCCON);
+			writew(tmp & ~S3C2410_RTCCON_CLKRST,
+				base + S3C2410_RTCCON);
 		}
 	}
+	clk_disable(rtc_clk);
 }
 
 static int s3c_rtc_remove(struct platform_device *dev)
 {
-	struct rtc_device *rtc = platform_get_drvdata(dev);
+	s3c_rtc_setaie(&dev->dev, 0);
 
-	platform_set_drvdata(dev, NULL);
-	rtc_device_unregister(rtc);
+	clk_unprepare(rtc_clk);
+	rtc_clk = NULL;
 
-	s3c_rtc_setpie(0);
-	s3c_rtc_setaie(0);
+	return 0;
+}
 
-	iounmap(s3c_rtc_base);
-	release_resource(s3c_rtc_mem);
-	kfree(s3c_rtc_mem);
+static const struct of_device_id s3c_rtc_dt_match[];
 
-	return 0;
+static inline int s3c_rtc_get_driver_data(struct platform_device *pdev)
+{
+#ifdef CONFIG_OF
+	struct s3c_rtc_drv_data *data;
+	if (pdev->dev.of_node) {
+		const struct of_device_id *match;
+		match = of_match_node(s3c_rtc_dt_match, pdev->dev.of_node);
+		data = (struct s3c_rtc_drv_data *) match->data;
+		return data->cpu_type;
+	}
+#endif
+	return platform_get_device_id(pdev)->driver_data;
 }
 
 static int s3c_rtc_probe(struct platform_device *pdev)
 {
 	struct rtc_device *rtc;
+	struct rtc_time rtc_tm;
 	struct resource *res;
 	int ret;
+	int tmp;
 
-	pr_debug("%s: probe=%p\n", __FUNCTION__, pdev);
+	dev_dbg(&pdev->dev, "%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;
+		return s3c_rtc_tickno;
 	}
 
 	s3c_rtc_alarmno = platform_get_irq(pdev, 0);
 	if (s3c_rtc_alarmno < 0) {
 		dev_err(&pdev->dev, "no irq for alarm\n");
-		return -ENOENT;
+		return s3c_rtc_alarmno;
 	}
 
-	pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
+	dev_dbg(&pdev->dev, "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 = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(s3c_rtc_base))
+		return PTR_ERR(s3c_rtc_base);
+
+	rtc_clk = devm_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;
+		return ret;
 	}
 
-	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;
-	}
+	clk_prepare_enable(rtc_clk);
 
 	/* 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));
+	dev_dbg(&pdev->dev, "s3c2410_rtc: RTCCON=%02x\n",
+		 readw(s3c_rtc_base + S3C2410_RTCCON));
 
-	s3c_rtc_setfreq(s3c_rtc_freq);
+	device_init_wakeup(&pdev->dev, 1);
 
 	/* register RTC and exit */
 
-	rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops,
+	rtc = devm_rtc_device_register(&pdev->dev, "s3c", &s3c_rtcops,
 				  THIS_MODULE);
 
 	if (IS_ERR(rtc)) {
@@ -521,74 +509,188 @@ static int s3c_rtc_probe(struct platform_device *pdev)
 		goto err_nortc;
 	}
 
-	rtc->max_user_freq = 128;
+	s3c_rtc_cpu_type = s3c_rtc_get_driver_data(pdev);
+
+	/* 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_S3C2410)
+		rtc->max_user_freq = 32768;
+	else
+		rtc->max_user_freq = 128;
+
+	if (s3c_rtc_cpu_type == TYPE_S3C2416 || s3c_rtc_cpu_type == TYPE_S3C2443) {
+		tmp = readw(s3c_rtc_base + S3C2410_RTCCON);
+		tmp |= S3C2443_RTCCON_TICSEL;
+		writew(tmp, s3c_rtc_base + S3C2410_RTCCON);
+	}
 
 	platform_set_drvdata(pdev, rtc);
+
+	s3c_rtc_setfreq(&pdev->dev, 1);
+
+	ret = devm_request_irq(&pdev->dev, s3c_rtc_alarmno, s3c_rtc_alarmirq,
+			  0,  "s3c2410-rtc alarm", rtc);
+	if (ret) {
+		dev_err(&pdev->dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret);
+		goto err_nortc;
+	}
+
+	ret = devm_request_irq(&pdev->dev, s3c_rtc_tickno, s3c_rtc_tickirq,
+			  0,  "s3c2410-rtc tick", rtc);
+	if (ret) {
+		dev_err(&pdev->dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret);
+		goto err_nortc;
+	}
+
+	clk_disable(rtc_clk);
+
 	return 0;
 
  err_nortc:
 	s3c_rtc_enable(pdev, 0);
-	iounmap(s3c_rtc_base);
-
- err_nomap:
-	release_resource(s3c_rtc_mem);
+	clk_disable_unprepare(rtc_clk);
 
- err_nores:
 	return ret;
 }
 
-#ifdef CONFIG_PM
-
+#ifdef CONFIG_PM_SLEEP
 /* RTC Power management control */
 
-static int ticnt_save;
+static int ticnt_save, ticnt_en_save;
+static bool wake_en;
 
-static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
+static int s3c_rtc_suspend(struct device *dev)
 {
+	struct platform_device *pdev = to_platform_device(dev);
+
+	clk_enable(rtc_clk);
 	/* 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;
+		ticnt_save = readl(s3c_rtc_base + S3C2410_TICNT);
+	} else {
+		ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
+	}
 	s3c_rtc_enable(pdev, 0);
+
+	if (device_may_wakeup(dev) && !wake_en) {
+		if (enable_irq_wake(s3c_rtc_alarmno) == 0)
+			wake_en = true;
+		else
+			dev_err(dev, "enable_irq_wake failed\n");
+	}
+	clk_disable(rtc_clk);
+
 	return 0;
 }
 
-static int s3c_rtc_resume(struct platform_device *pdev)
+static int s3c_rtc_resume(struct device *dev)
 {
+	struct platform_device *pdev = to_platform_device(dev);
+	unsigned int tmp;
+
+	clk_enable(rtc_clk);
 	s3c_rtc_enable(pdev, 1);
-	writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
+	if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
+		writel(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
+		if (ticnt_en_save) {
+			tmp = readw(s3c_rtc_base + S3C2410_RTCCON);
+			writew(tmp | ticnt_en_save,
+					s3c_rtc_base + S3C2410_RTCCON);
+		}
+	} else {
+		writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
+	}
+
+	if (device_may_wakeup(dev) && wake_en) {
+		disable_irq_wake(s3c_rtc_alarmno);
+		wake_en = false;
+	}
+	clk_disable(rtc_clk);
+
 	return 0;
 }
-#else
-#define s3c_rtc_suspend NULL
-#define s3c_rtc_resume  NULL
 #endif
 
-static struct platform_driver s3c2410_rtcdrv = {
+static SIMPLE_DEV_PM_OPS(s3c_rtc_pm_ops, s3c_rtc_suspend, s3c_rtc_resume);
+
+#ifdef CONFIG_OF
+static struct s3c_rtc_drv_data s3c_rtc_drv_data_array[] = {
+	[TYPE_S3C2410] = { TYPE_S3C2410 },
+	[TYPE_S3C2416] = { TYPE_S3C2416 },
+	[TYPE_S3C2443] = { TYPE_S3C2443 },
+	[TYPE_S3C64XX] = { TYPE_S3C64XX },
+};
+
+static const struct of_device_id s3c_rtc_dt_match[] = {
+	{
+		.compatible = "samsung,s3c2410-rtc",
+		.data = &s3c_rtc_drv_data_array[TYPE_S3C2410],
+	}, {
+		.compatible = "samsung,s3c2416-rtc",
+		.data = &s3c_rtc_drv_data_array[TYPE_S3C2416],
+	}, {
+		.compatible = "samsung,s3c2443-rtc",
+		.data = &s3c_rtc_drv_data_array[TYPE_S3C2443],
+	}, {
+		.compatible = "samsung,s3c6410-rtc",
+		.data = &s3c_rtc_drv_data_array[TYPE_S3C64XX],
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, s3c_rtc_dt_match);
+#endif
+
+static struct platform_device_id s3c_rtc_driver_ids[] = {
+	{
+		.name		= "s3c2410-rtc",
+		.driver_data	= TYPE_S3C2410,
+	}, {
+		.name		= "s3c2416-rtc",
+		.driver_data	= TYPE_S3C2416,
+	}, {
+		.name		= "s3c2443-rtc",
+		.driver_data	= TYPE_S3C2443,
+	}, {
+		.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		= s3c_rtc_remove,
-	.suspend	= s3c_rtc_suspend,
-	.resume		= s3c_rtc_resume,
+	.id_table	= s3c_rtc_driver_ids,
 	.driver		= {
-		.name	= "s3c2410-rtc",
+		.name	= "s3c-rtc",
 		.owner	= THIS_MODULE,
+		.pm	= &s3c_rtc_pm_ops,
+		.of_match_table	= of_match_ptr(s3c_rtc_dt_match),
 	},
 };
 
-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_platform_driver(s3c_rtc_driver);
 
 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
 MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:s3c2410-rtc");