[RFC PATCH v3 6/8] rtc/mxc: Convert get_alarm_or_time()/set_alarm_or_time() to use time64_t

From: Xunlei Pang
Date: Tue Jan 20 2015 - 11:22:57 EST


We want to convert mxc_rtc_set_mmss() to use rtc_class_ops's set_mmss64(),
but it uses get_alarm_or_time()/set_alarm_or_time() internal interfaces
which are y2038 unsafe.

So here as a separate patch, it converts these two internal interfaces
of "mxc" to use safe time64_t to make some preparations.

Signed-off-by: Xunlei Pang <pang.xunlei@xxxxxxxxxx>
---
drivers/rtc/rtc-mxc.c | 29 ++++++++++++++---------------
1 file changed, 14 insertions(+), 15 deletions(-)

diff --git a/drivers/rtc/rtc-mxc.c b/drivers/rtc/rtc-mxc.c
index a7b218f..83cba23 100644
--- a/drivers/rtc/rtc-mxc.c
+++ b/drivers/rtc/rtc-mxc.c
@@ -106,7 +106,7 @@ static inline int is_imx1_rtc(struct rtc_plat_data *data)
* This function is used to obtain the RTC time or the alarm value in
* second.
*/
-static u32 get_alarm_or_time(struct device *dev, int time_alarm)
+static time64_t get_alarm_or_time(struct device *dev, int time_alarm)
{
struct platform_device *pdev = to_platform_device(dev);
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
@@ -129,29 +129,28 @@ static u32 get_alarm_or_time(struct device *dev, int time_alarm)
hr = hr_min >> 8;
min = hr_min & 0xff;

- return (((day * 24 + hr) * 60) + min) * 60 + sec;
+ return ((((time64_t)day * 24 + hr) * 60) + min) * 60 + sec;
}

/*
* This function sets the RTC alarm value or the time value.
*/
-static void set_alarm_or_time(struct device *dev, int time_alarm, u32 time)
+static void set_alarm_or_time(struct device *dev, int time_alarm, time64_t time)
{
- u32 day, hr, min, sec, temp;
+ u32 tod, day, hr, min, sec, temp;
struct platform_device *pdev = to_platform_device(dev);
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
void __iomem *ioaddr = pdata->ioaddr;

- day = time / 86400;
- time -= day * 86400;
+ day = div_s64_rem(time, 86400, &tod);

/* time is within a day now */
- hr = time / 3600;
- time -= hr * 3600;
+ hr = tod / 3600;
+ tod -= hr * 3600;

/* time is within an hour now */
- min = time / 60;
- sec = time - min * 60;
+ min = tod / 60;
+ sec = tod - min * 60;

temp = (hr << 8) + min;

@@ -175,12 +174,12 @@ static void set_alarm_or_time(struct device *dev, int time_alarm, u32 time)
*/
static void rtc_update_alarm(struct device *dev, struct rtc_time *alrm)
{
- unsigned long time;
+ time64_t time;
struct platform_device *pdev = to_platform_device(dev);
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
void __iomem *ioaddr = pdata->ioaddr;

- rtc_tm_to_time(alrm, &time);
+ time = rtc_tm_to_time64(alrm);

/* clear all the interrupt status bits */
writew(readw(ioaddr + RTC_RTCISR), ioaddr + RTC_RTCISR);
@@ -272,14 +271,14 @@ static int mxc_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
*/
static int mxc_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
- u32 val;
+ time64_t val;

/* Avoid roll-over from reading the different registers */
do {
val = get_alarm_or_time(dev, MXC_RTC_TIME);
} while (val != get_alarm_or_time(dev, MXC_RTC_TIME));

- rtc_time_to_tm(val, tm);
+ rtc_time64_to_tm(val, tm);

return 0;
}
@@ -322,7 +321,7 @@ static int mxc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
void __iomem *ioaddr = pdata->ioaddr;

- rtc_time_to_tm(get_alarm_or_time(dev, MXC_RTC_ALARM), &alrm->time);
+ rtc_time64_to_tm(get_alarm_or_time(dev, MXC_RTC_ALARM), &alrm->time);
alrm->pending = ((readw(ioaddr + RTC_RTCISR) & RTC_ALM_BIT)) ? 1 : 0;

return 0;
--
1.9.1

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