tmp_suning_uos_patched/drivers/rtc/rtc-mv.c
Thomas Petazzoni e102dc7a54 rtc: mv: reset date if after year 2038
Dates after January, 19th 2038 are badly handled by userspace due to
the time being stored on 32 bits. This causes issues on some Marvell
platform on which the RTC is initialized by default to a date that's
beyond 2038, causing a really weird behavior of the RTC.

In order to avoid that, reset the date to a sane value if the RTC is
beyond 2038.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-02-21 23:29:05 +00:00

343 lines
9.2 KiB
C

/*
* 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 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",
.owner = THIS_MODULE,
.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");