drivers/rtc/mxc: Convert get_alarm_or_time()/set_alarm_or_time() to use time64_t

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@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1427945681-29972-13-git-send-email-john.stultz@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/drivers/rtc/rtc-mxc.c b/drivers/rtc/rtc-mxc.c
index a7b218ff078d67d38b466231581b63eff69b44bd..83cba23a6b00aaa445088a9b0c4abb0a16f107e2 100644 (file)
--- 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;