diff options
Diffstat (limited to 'drivers/rtc/rtc-mv.c')
| -rw-r--r-- | drivers/rtc/rtc-mv.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-mv.c b/drivers/rtc/rtc-mv.c new file mode 100644 index 000000000000..45f12dcd3716 --- /dev/null +++ b/drivers/rtc/rtc-mv.c @@ -0,0 +1,163 @@ +/* + * 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> + + +#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 + + +struct rtc_plat_data { + struct rtc_device *rtc; + void __iomem *ioaddr; +}; + +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 const struct rtc_class_ops mv_rtc_ops = { + .read_time = mv_rtc_read_time, + .set_time = mv_rtc_set_time, +}; + +static int __init mv_rtc_probe(struct platform_device *pdev) +{ + struct resource *res; + struct rtc_plat_data *pdata; + resource_size_t size; + u32 rtc_time; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENODEV; + + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return -ENOMEM; + + size = resource_size(res); + if (!devm_request_mem_region(&pdev->dev, res->start, size, + pdev->name)) + return -EBUSY; + + pdata->ioaddr = devm_ioremap(&pdev->dev, res->start, size); + if (!pdata->ioaddr) + return -ENOMEM; + + /* 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"); + return -EINVAL; + } + + platform_set_drvdata(pdev, pdata); + pdata->rtc = rtc_device_register(pdev->name, &pdev->dev, + &mv_rtc_ops, THIS_MODULE); + if (IS_ERR(pdata->rtc)) + return PTR_ERR(pdata->rtc); + + return 0; +} + +static int __exit mv_rtc_remove(struct platform_device *pdev) +{ + struct rtc_plat_data *pdata = platform_get_drvdata(pdev); + + rtc_device_unregister(pdata->rtc); + return 0; +} + +static struct platform_driver mv_rtc_driver = { + .remove = __exit_p(mv_rtc_remove), + .driver = { + .name = "rtc-mv", + .owner = THIS_MODULE, + }, +}; + +static __init int mv_init(void) +{ + return platform_driver_probe(&mv_rtc_driver, mv_rtc_probe); +} + +static __exit void mv_exit(void) +{ + platform_driver_unregister(&mv_rtc_driver); +} + +module_init(mv_init); +module_exit(mv_exit); + +MODULE_AUTHOR("Saeed Bishara <saeed@marvell.com>"); +MODULE_DESCRIPTION("Marvell RTC driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:rtc-mv"); |
