On first RTC boot it has the month register value set to 0.
Unconditional subtracting of 1 subsequently in s3c_rtc_gettime() leads
to the next error message in kernel log:
hctosys: unable to read the hardware clock
That happens in s3c_rtc_probe() when trying to register the RTC, which
in turn tries to read and validate the time. Initialize RTC date/time
registers to valid values in probe function on the first boot to prevent
such errors.
Signed-off-by: Sam Protsenko <semen.protsenko@xxxxxxxxxx>
---
drivers/rtc/rtc-s3c.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)
diff --git a/drivers/rtc/rtc-s3c.c b/drivers/rtc/rtc-s3c.c
index 238928e29fbc..c7e763bcf61f 100644
--- a/drivers/rtc/rtc-s3c.c
+++ b/drivers/rtc/rtc-s3c.c
@@ -403,6 +403,28 @@ static int s3c_rtc_remove(struct platform_device *pdev)
return 0;
}
+/* Set RTC with valid date/time values on first boot */
+static int s3c_rtc_init_time(struct s3c_rtc *info)
+{
+ struct rtc_time tm;
+ int ret;
+
+ ret = s3c_rtc_read_time(info, &tm);
+ if (ret)
+ return ret;
+
+ /* Only init RTC date/time on first boot */
+ if (tm.tm_mday > 0)
+ return 0;
+
+ /* Init date/time: 1 Jan 2000 00:00:00 */
+ memset(&tm, 0, sizeof(struct rtc_time));
+ tm.tm_mday = 1; /* tm_mday min valid value is 1 */
+ tm.tm_mon = 1; /* January in internal representation */
+
+ return s3c_rtc_write_time(info, &tm);
+}
+
static int s3c_rtc_probe(struct platform_device *pdev)
{
struct s3c_rtc *info = NULL;
@@ -471,6 +493,10 @@ static int s3c_rtc_probe(struct platform_device *pdev)
device_init_wakeup(&pdev->dev, 1);
+ ret = s3c_rtc_init_time(info);
+ if (ret)
+ goto err_nortc;
+
info->rtc = devm_rtc_allocate_device(&pdev->dev);
if (IS_ERR(info->rtc)) {
ret = PTR_ERR(info->rtc);
--
2.30.2
