/* * 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");