/*
* 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");
