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

From: Yauhen Kharuzhy
Date: Sun Nov 06 2011 - 11:47:18 EST


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@xxxxxxxxx>
---
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

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