Initial import

1 files changed, 273 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-nuc900.c b/drivers/rtc/rtc-nuc900.c
new file mode 100644
index 000000000..09fc1c19f
--- /dev/null
+++ b/drivers/rtc/rtc-nuc900.c
@@ -0,0 +1,273 @@
+/*
+ * Copyright (c) 2008-2009 Nuvoton technology corporation.
+ *
+ * Wan ZongShun <mcuos.com@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation;version 2 of the License.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/rtc.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/bcd.h>
+
+/* RTC Control Registers */
+#define REG_RTC_INIR		0x00
+#define REG_RTC_AER		0x04
+#define REG_RTC_FCR		0x08
+#define REG_RTC_TLR		0x0C
+#define REG_RTC_CLR		0x10
+#define REG_RTC_TSSR		0x14
+#define REG_RTC_DWR		0x18
+#define REG_RTC_TAR		0x1C
+#define REG_RTC_CAR		0x20
+#define REG_RTC_LIR		0x24
+#define REG_RTC_RIER		0x28
+#define REG_RTC_RIIR		0x2C
+#define REG_RTC_TTR		0x30
+
+#define RTCSET			0x01
+#define AERRWENB		0x10000
+#define INIRRESET		0xa5eb1357
+#define AERPOWERON		0xA965
+#define AERPOWEROFF		0x0000
+#define LEAPYEAR		0x0001
+#define TICKENB			0x80
+#define TICKINTENB		0x0002
+#define ALARMINTENB		0x0001
+#define MODE24			0x0001
+
+struct nuc900_rtc {
+	int			irq_num;
+	void __iomem		*rtc_reg;
+	struct rtc_device	*rtcdev;
+};
+
+struct nuc900_bcd_time {
+	int bcd_sec;
+	int bcd_min;
+	int bcd_hour;
+	int bcd_mday;
+	int bcd_mon;
+	int bcd_year;
+};
+
+static irqreturn_t nuc900_rtc_interrupt(int irq, void *_rtc)
+{
+	struct nuc900_rtc *rtc = _rtc;
+	unsigned long events = 0, rtc_irq;
+
+	rtc_irq = __raw_readl(rtc->rtc_reg + REG_RTC_RIIR);
+
+	if (rtc_irq & ALARMINTENB) {
+		rtc_irq &= ~ALARMINTENB;
+		__raw_writel(rtc_irq, rtc->rtc_reg + REG_RTC_RIIR);
+		events |= RTC_AF | RTC_IRQF;
+	}
+
+	if (rtc_irq & TICKINTENB) {
+		rtc_irq &= ~TICKINTENB;
+		__raw_writel(rtc_irq, rtc->rtc_reg + REG_RTC_RIIR);
+		events |= RTC_UF | RTC_IRQF;
+	}
+
+	rtc_update_irq(rtc->rtcdev, 1, events);
+
+	return IRQ_HANDLED;
+}
+
+static int *check_rtc_access_enable(struct nuc900_rtc *nuc900_rtc)
+{
+	unsigned int timeout = 0x1000;
+	__raw_writel(INIRRESET, nuc900_rtc->rtc_reg + REG_RTC_INIR);
+
+	mdelay(10);
+
+	__raw_writel(AERPOWERON, nuc900_rtc->rtc_reg + REG_RTC_AER);
+
+	while (!(__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_AER) & AERRWENB)
+								&& timeout--)
+		mdelay(1);
+
+	if (!timeout)
+		return ERR_PTR(-EPERM);
+
+	return NULL;
+}
+
+static int nuc900_rtc_bcd2bin(unsigned int timereg,
+				unsigned int calreg, struct rtc_time *tm)
+{
+	tm->tm_mday	= bcd2bin(calreg >> 0);
+	tm->tm_mon	= bcd2bin(calreg >> 8);
+	tm->tm_year	= bcd2bin(calreg >> 16) + 100;
+
+	tm->tm_sec	= bcd2bin(timereg >> 0);
+	tm->tm_min	= bcd2bin(timereg >> 8);
+	tm->tm_hour	= bcd2bin(timereg >> 16);
+
+	return rtc_valid_tm(tm);
+}
+
+static void nuc900_rtc_bin2bcd(struct device *dev, struct rtc_time *settm,
+						struct nuc900_bcd_time *gettm)
+{
+	gettm->bcd_mday = bin2bcd(settm->tm_mday) << 0;
+	gettm->bcd_mon  = bin2bcd(settm->tm_mon) << 8;
+
+	if (settm->tm_year < 100) {
+		dev_warn(dev, "The year will be between 1970-1999, right?\n");
+		gettm->bcd_year = bin2bcd(settm->tm_year) << 16;
+	} else {
+		gettm->bcd_year = bin2bcd(settm->tm_year - 100) << 16;
+	}
+
+	gettm->bcd_sec  = bin2bcd(settm->tm_sec) << 0;
+	gettm->bcd_min  = bin2bcd(settm->tm_min) << 8;
+	gettm->bcd_hour = bin2bcd(settm->tm_hour) << 16;
+}
+
+static int nuc900_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
+
+	if (enabled)
+		__raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)|
+				(ALARMINTENB), rtc->rtc_reg + REG_RTC_RIER);
+	else
+		__raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)&
+				(~ALARMINTENB), rtc->rtc_reg + REG_RTC_RIER);
+
+	return 0;
+}
+
+static int nuc900_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
+	unsigned int timeval, clrval;
+
+	timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TLR);
+	clrval	= __raw_readl(rtc->rtc_reg + REG_RTC_CLR);
+
+	return nuc900_rtc_bcd2bin(timeval, clrval, tm);
+}
+
+static int nuc900_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
+	struct nuc900_bcd_time gettm;
+	unsigned long val;
+	int *err;
+
+	nuc900_rtc_bin2bcd(dev, tm, &gettm);
+
+	err = check_rtc_access_enable(rtc);
+	if (IS_ERR(err))
+		return PTR_ERR(err);
+
+	val = gettm.bcd_mday | gettm.bcd_mon | gettm.bcd_year;
+	__raw_writel(val, rtc->rtc_reg + REG_RTC_CLR);
+
+	val = gettm.bcd_sec | gettm.bcd_min | gettm.bcd_hour;
+	__raw_writel(val, rtc->rtc_reg + REG_RTC_TLR);
+
+	return 0;
+}
+
+static int nuc900_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
+	unsigned int timeval, carval;
+
+	timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TAR);
+	carval	= __raw_readl(rtc->rtc_reg + REG_RTC_CAR);
+
+	return nuc900_rtc_bcd2bin(timeval, carval, &alrm->time);
+}
+
+static int nuc900_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
+	struct nuc900_bcd_time tm;
+	unsigned long val;
+	int *err;
+
+	nuc900_rtc_bin2bcd(dev, &alrm->time, &tm);
+
+	err = check_rtc_access_enable(rtc);
+	if (IS_ERR(err))
+		return PTR_ERR(err);
+
+	val = tm.bcd_mday | tm.bcd_mon | tm.bcd_year;
+	__raw_writel(val, rtc->rtc_reg + REG_RTC_CAR);
+
+	val = tm.bcd_sec | tm.bcd_min | tm.bcd_hour;
+	__raw_writel(val, rtc->rtc_reg + REG_RTC_TAR);
+
+	return 0;
+}
+
+static struct rtc_class_ops nuc900_rtc_ops = {
+	.read_time = nuc900_rtc_read_time,
+	.set_time = nuc900_rtc_set_time,
+	.read_alarm = nuc900_rtc_read_alarm,
+	.set_alarm = nuc900_rtc_set_alarm,
+	.alarm_irq_enable = nuc900_alarm_irq_enable,
+};
+
+static int __init nuc900_rtc_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct nuc900_rtc *nuc900_rtc;
+
+	nuc900_rtc = devm_kzalloc(&pdev->dev, sizeof(struct nuc900_rtc),
+				GFP_KERNEL);
+	if (!nuc900_rtc)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	nuc900_rtc->rtc_reg = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(nuc900_rtc->rtc_reg))
+		return PTR_ERR(nuc900_rtc->rtc_reg);
+
+	platform_set_drvdata(pdev, nuc900_rtc);
+
+	nuc900_rtc->rtcdev = devm_rtc_device_register(&pdev->dev, pdev->name,
+						&nuc900_rtc_ops, THIS_MODULE);
+	if (IS_ERR(nuc900_rtc->rtcdev)) {
+		dev_err(&pdev->dev, "rtc device register failed\n");
+		return PTR_ERR(nuc900_rtc->rtcdev);
+	}
+
+	__raw_writel(__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_TSSR) | MODE24,
+					nuc900_rtc->rtc_reg + REG_RTC_TSSR);
+
+	nuc900_rtc->irq_num = platform_get_irq(pdev, 0);
+	if (devm_request_irq(&pdev->dev, nuc900_rtc->irq_num,
+			nuc900_rtc_interrupt, 0, "nuc900rtc", nuc900_rtc)) {
+		dev_err(&pdev->dev, "NUC900 RTC request irq failed\n");
+		return -EBUSY;
+	}
+
+	return 0;
+}
+
+static struct platform_driver nuc900_rtc_driver = {
+	.driver		= {
+		.name	= "nuc900-rtc",
+	},
+};
+
+module_platform_driver_probe(nuc900_rtc_driver, nuc900_rtc_probe);
+
+MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>");
+MODULE_DESCRIPTION("nuc910/nuc920 RTC driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:nuc900-rtc");