diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/rtc/rtc-nuc900.c | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-nuc900.c b/drivers/rtc/rtc-nuc900.c new file mode 100644 index 000000000..7da664a77 --- /dev/null +++ b/drivers/rtc/rtc-nuc900.c @@ -0,0 +1,275 @@ +/* + * 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 void 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); +} + +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); + + nuc900_rtc_bcd2bin(timeval, clrval, tm); + + return 0; +} + +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); + + nuc900_rtc_bcd2bin(timeval, carval, &alrm->time); + + return rtc_valid_tm(&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 const 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"); |