/* * Driver for the RTC in Marvell SoCs. * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. */ #include <linux/init.h> #include <linux/kernel.h> #include <linux/rtc.h> #include <linux/bcd.h> #include <linux/io.h> #include <linux/platform_device.h> #include <linux/of.h> #include <linux/delay.h> #include <linux/clk.h> #include <linux/gfp.h> #include <linux/module.h> #define RTC_TIME_REG_OFFS 0 #define RTC_SECONDS_OFFS 0 #define RTC_MINUTES_OFFS 8 #define RTC_HOURS_OFFS 16 #define RTC_WDAY_OFFS 24 #define RTC_HOURS_12H_MODE (1 << 22) /* 12 hours mode */ #define RTC_DATE_REG_OFFS 4 #define RTC_MDAY_OFFS 0 #define RTC_MONTH_OFFS 8 #define RTC_YEAR_OFFS 16 #define RTC_ALARM_TIME_REG_OFFS 8 #define RTC_ALARM_DATE_REG_OFFS 0xc #define RTC_ALARM_VALID (1 << 7) #define RTC_ALARM_INTERRUPT_MASK_REG_OFFS 0x10 #define RTC_ALARM_INTERRUPT_CASUE_REG_OFFS 0x14 struct rtc_plat_data { struct rtc_device *rtc; void __iomem *ioaddr; int irq; struct clk *clk; }; static int mv_rtc_set_time(struct device *dev, struct rtc_time *tm) { struct rtc_plat_data *pdata = dev_get_drvdata(dev); void __iomem *ioaddr = pdata->ioaddr; u32 rtc_reg; rtc_reg = (bin2bcd(tm->tm_sec) << RTC_SECONDS_OFFS) | (bin2bcd(tm->tm_min) << RTC_MINUTES_OFFS) | (bin2bcd(tm->tm_hour) << RTC_HOURS_OFFS) | (bin2bcd(tm->tm_wday) << RTC_WDAY_OFFS); writel(rtc_reg, ioaddr + RTC_TIME_REG_OFFS); rtc_reg = (bin2bcd(tm->tm_mday) << RTC_MDAY_OFFS) | (bin2bcd(tm->tm_mon + 1) << RTC_MONTH_OFFS) | (bin2bcd(tm->tm_year % 100) << RTC_YEAR_OFFS); writel(rtc_reg, ioaddr + RTC_DATE_REG_OFFS); return 0; } static int mv_rtc_read_time(struct device *dev, struct rtc_time *tm) { struct rtc_plat_data *pdata = dev_get_drvdata(dev); void __iomem *ioaddr = pdata->ioaddr; u32 rtc_time, rtc_date; unsigned int year, month, day, hour, minute, second, wday; rtc_time = readl(ioaddr + RTC_TIME_REG_OFFS); rtc_date = readl(ioaddr + RTC_DATE_REG_OFFS); second = rtc_time & 0x7f; minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f; hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hours mode */ wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7; day = rtc_date & 0x3f; month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f; year = (rtc_date >> RTC_YEAR_OFFS) & 0xff; tm->tm_sec = bcd2bin(second); tm->tm_min = bcd2bin(minute); tm->tm_hour = bcd2bin(hour); tm->tm_mday = bcd2bin(day); tm->tm_wday = bcd2bin(wday); tm->tm_mon = bcd2bin(month) - 1; /* hw counts from year 2000, but tm_year is relative to 1900 */ tm->tm_year = bcd2bin(year) + 100; return rtc_valid_tm(tm); } static int mv_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) { struct rtc_plat_data *pdata = dev_get_drvdata(dev); void __iomem *ioaddr = pdata->ioaddr; u32 rtc_time, rtc_date; unsigned int year, month, day, hour, minute, second, wday; rtc_time = readl(ioaddr + RTC_ALARM_TIME_REG_OFFS); rtc_date = readl(ioaddr + RTC_ALARM_DATE_REG_OFFS); second = rtc_time & 0x7f; minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f; hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hours mode */ wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7; day = rtc_date & 0x3f; month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f; year = (rtc_date >> RTC_YEAR_OFFS) & 0xff; alm->time.tm_sec = bcd2bin(second); alm->time.tm_min = bcd2bin(minute); alm->time.tm_hour = bcd2bin(hour); alm->time.tm_mday = bcd2bin(day); alm->time.tm_wday = bcd2bin(wday); alm->time.tm_mon = bcd2bin(month) - 1; /* hw counts from year 2000, but tm_year is relative to 1900 */ alm->time.tm_year = bcd2bin(year) + 100; if (rtc_valid_tm(&alm->time) < 0) { dev_err(dev, "retrieved alarm date/time is not valid.\n"); rtc_time_to_tm(0, &alm->time); } alm->enabled = !!readl(ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); return 0; } static int mv_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) { struct rtc_plat_data *pdata = dev_get_drvdata(dev); void __iomem *ioaddr = pdata->ioaddr; u32 rtc_reg = 0; if (alm->time.tm_sec >= 0) rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_sec)) << RTC_SECONDS_OFFS; if (alm->time.tm_min >= 0) rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_min)) << RTC_MINUTES_OFFS; if (alm->time.tm_hour >= 0) rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_hour)) << RTC_HOURS_OFFS; writel(rtc_reg, ioaddr + RTC_ALARM_TIME_REG_OFFS); if (alm->time.tm_mday >= 0) rtc_reg = (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mday)) << RTC_MDAY_OFFS; else rtc_reg = 0; if (alm->time.tm_mon >= 0) rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mon + 1)) << RTC_MONTH_OFFS; if (alm->time.tm_year >= 0) rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_year % 100)) << RTC_YEAR_OFFS; writel(rtc_reg, ioaddr + RTC_ALARM_DATE_REG_OFFS); writel(0, ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS); writel(alm->enabled ? 1 : 0, ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); return 0; } static int mv_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct platform_device *pdev = to_platform_device(dev); struct rtc_plat_data *pdata = platform_get_drvdata(pdev); void __iomem *ioaddr = pdata->ioaddr; if (pdata->irq < 0) return -EINVAL; /* fall back into rtc-dev's emulation */ if (enabled) writel(1, ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); else writel(0, ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); return 0; } static irqreturn_t mv_rtc_interrupt(int irq, void *data) { struct rtc_plat_data *pdata = data; void __iomem *ioaddr = pdata->ioaddr; /* alarm irq? */ if (!readl(ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS)) return IRQ_NONE; /* clear interrupt */ writel(0, ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS); rtc_update_irq(pdata->rtc, 1, RTC_IRQF | RTC_AF); return IRQ_HANDLED; } static const struct rtc_class_ops mv_rtc_ops = { .read_time = mv_rtc_read_time, .set_time = mv_rtc_set_time, }; static const struct rtc_class_ops mv_rtc_alarm_ops = { .read_time = mv_rtc_read_time, .set_time = mv_rtc_set_time, .read_alarm = mv_rtc_read_alarm, .set_alarm = mv_rtc_set_alarm, .alarm_irq_enable = mv_rtc_alarm_irq_enable, }; static int __init mv_rtc_probe(struct platform_device *pdev) { struct resource *res; struct rtc_plat_data *pdata; u32 rtc_time; u32 rtc_date; int ret = 0; pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); if (!pdata) return -ENOMEM; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); pdata->ioaddr = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(pdata->ioaddr)) return PTR_ERR(pdata->ioaddr); pdata->clk = devm_clk_get(&pdev->dev, NULL); /* Not all SoCs require a clock.*/ if (!IS_ERR(pdata->clk)) clk_prepare_enable(pdata->clk); /* make sure the 24 hours mode is enabled */ rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS); if (rtc_time & RTC_HOURS_12H_MODE) { dev_err(&pdev->dev, "24 Hours mode not supported.\n"); ret = -EINVAL; goto out; } /* make sure it is actually functional */ if (rtc_time == 0x01000000) { ssleep(1); rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS); if (rtc_time == 0x01000000) { dev_err(&pdev->dev, "internal RTC not ticking\n"); ret = -ENODEV; goto out; } } /* * A date after January 19th, 2038 does not fit on 32 bits and * will confuse the kernel and userspace. Reset to a sane date * (January 1st, 2013) if we're after 2038. */ rtc_date = readl(pdata->ioaddr + RTC_DATE_REG_OFFS); if (bcd2bin((rtc_date >> RTC_YEAR_OFFS) & 0xff) >= 38) { dev_info(&pdev->dev, "invalid RTC date, resetting to January 1st, 2013\n"); writel(0x130101, pdata->ioaddr + RTC_DATE_REG_OFFS); } pdata->irq = platform_get_irq(pdev, 0); platform_set_drvdata(pdev, pdata); if (pdata->irq >= 0) { device_init_wakeup(&pdev->dev, 1); pdata->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, &mv_rtc_alarm_ops, THIS_MODULE); } else { pdata->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, &mv_rtc_ops, THIS_MODULE); } if (IS_ERR(pdata->rtc)) { ret = PTR_ERR(pdata->rtc); goto out; } if (pdata->irq >= 0) { writel(0, pdata->ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); if (devm_request_irq(&pdev->dev, pdata->irq, mv_rtc_interrupt, IRQF_SHARED, pdev->name, pdata) < 0) { dev_warn(&pdev->dev, "interrupt not available.\n"); pdata->irq = -1; } } return 0; out: if (!IS_ERR(pdata->clk)) clk_disable_unprepare(pdata->clk); return ret; } static int __exit mv_rtc_remove(struct platform_device *pdev) { struct rtc_plat_data *pdata = platform_get_drvdata(pdev); if (pdata->irq >= 0) device_init_wakeup(&pdev->dev, 0); if (!IS_ERR(pdata->clk)) clk_disable_unprepare(pdata->clk); return 0; } #ifdef CONFIG_OF static const struct of_device_id rtc_mv_of_match_table[] = { { .compatible = "marvell,orion-rtc", }, {} }; #endif static struct platform_driver mv_rtc_driver = { .remove = __exit_p(mv_rtc_remove), .driver = { .name = "rtc-mv", .of_match_table = of_match_ptr(rtc_mv_of_match_table), }, }; module_platform_driver_probe(mv_rtc_driver, mv_rtc_probe); MODULE_AUTHOR("Saeed Bishara <saeed@marvell.com>"); MODULE_DESCRIPTION("Marvell RTC driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:rtc-mv");