diff options
Diffstat (limited to 'drivers/rtc/rtc-mv.c')
| -rw-r--r-- | drivers/rtc/rtc-mv.c | 330 |
1 files changed, 330 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-mv.c b/drivers/rtc/rtc-mv.c new file mode 100644 index 000000000..4b198b377 --- /dev/null +++ b/drivers/rtc/rtc-mv.c @@ -0,0 +1,330 @@ +/* + * 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/bitops.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 BIT(22) /* 12 hour 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 BIT(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 hour 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 0; +} + +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 hour 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 rtc_plat_data *pdata = dev_get_drvdata(dev); + 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; + 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 hour mode is enabled */ + rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS); + if (rtc_time & RTC_HOURS_12H_MODE) { + dev_err(&pdev->dev, "12 Hour mode is enabled but 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; + } + } + + 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", }, + {} +}; +MODULE_DEVICE_TABLE(of, rtc_mv_of_match_table); +#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"); |