1 files changed, 22 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-r9701.c b/drivers/rtc/rtc-r9701.c
index 7f8e6c247935..33b6ba0afa0d 100644
--- a/drivers/rtc/rtc-r9701.c
+++ b/drivers/rtc/rtc-r9701.c
@@ -122,6 +122,7 @@ static const struct rtc_class_ops r9701_rtc_ops = {
 static int __devinit r9701_probe(struct spi_device *spi)
 {
         struct rtc_device *rtc;
+        struct rtc_time dt;
         unsigned char tmp;
         int res;
 
@@ -132,6 +133,27 @@ static int __devinit r9701_probe(struct spi_device *spi)
                 return -ENODEV;
         }
 
+        /*
+         * The device seems to be present. Now check if the registers
+         * contain invalid values. If so, try to write a default date:
+         * 2000/1/1 00:00:00
+         */
+        r9701_get_datetime(&spi->dev, &dt);
+        if (rtc_valid_tm(&dt)) {
+                dev_info(&spi->dev, "trying to repair invalid date/time\n");
+                dt.tm_sec  = 0;
+                dt.tm_min  = 0;
+                dt.tm_hour = 0;
+                dt.tm_mday = 1;
+                dt.tm_mon  = 0;
+                dt.tm_year = 100;
+
+                if (r9701_set_datetime(&spi->dev, &dt)) {
+                        dev_err(&spi->dev, "cannot repair RTC register\n");
+                        return -ENODEV;
+                }
+        }
+
         rtc = rtc_device_register("r9701",
                                 &spi->dev, &r9701_rtc_ops, THIS_MODULE);
         if (IS_ERR(rtc))