[PATCH 1/2] RTC MXC: Fix setting time for MX1 SoC

[Yauhen Kharuzhy <jekhor@gmail.com>]

There is no way to track year in the i.MX1 RTC: Days Counter register is
9-bit wide only. Attempt to save date after 1970-01-01 plus 512 days
causes endless loop in mxc_rtc_set_mmss(). Fix this by resetting year to
1970.

Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com>
---
 drivers/rtc/rtc-mxc.c |   11 +++++++++++
 1 files changed, 11 insertions(+), 0 deletions(-)

diff --git a/drivers/rtc/rtc-mxc.c b/drivers/rtc/rtc-mxc.c
index 39e41fb..1cf6a0b 100644
--- a/drivers/rtc/rtc-mxc.c
+++ b/drivers/rtc/rtc-mxc.c
@@ -290,6 +290,17 @@ static int mxc_rtc_read_time(struct device *dev, struct rtc_time *tm)
  */
 static int mxc_rtc_set_mmss(struct device *dev, unsigned long time)
 {
+	/* RTC_DAYR register is 9-bit in MX1 SoC,
+	 * save time and day of year only
+	 */
+	if (cpu_is_mx1()) {
+		struct rtc_time tm;
+
+		rtc_time_to_tm(time, &tm);
+		tm.tm_year = 70;
+		rtc_tm_to_time(&tm, &time);
+	}
+
 	/* Avoid roll-over from reading the different registers */
 	do {
 		set_alarm_or_time(dev, MXC_RTC_TIME, time);
-- 
1.7.7.1