rtc: mv: reset date if after year 2038

[deliverable/linux.git] / drivers / rtc / rtc-mv.c

diff --git a/drivers/rtc/rtc-mv.c b/drivers/rtc/rtc-mv.c
index d536c5962c99f1e6477f63b377e7445c354c5d14..d15a999363fce2808cfcba6089cf8282dfedc48a 100644 (file)
--- a/drivers/rtc/rtc-mv.c
+++ b/drivers/rtc/rtc-mv.c
@@ -222,6 +222,7 @@ static int __init mv_rtc_probe(struct platform_device *pdev)
        struct resource *res;
        struct rtc_plat_data *pdata;
        u32 rtc_time;
+       u32 rtc_date;
        int ret = 0;
 
        pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
@@ -257,6 +258,17 @@ static int __init mv_rtc_probe(struct platform_device *pdev)
                }
        }
 
+       /*
+        * A date after January 19th, 2038 does not fit on 32 bits and
+        * will confuse the kernel and userspace. Reset to a sane date
+        * (January 1st, 2013) if we're after 2038.
+        */
+       rtc_date = readl(pdata->ioaddr + RTC_DATE_REG_OFFS);
+       if (bcd2bin((rtc_date >> RTC_YEAR_OFFS) & 0xff) >= 38) {
+               dev_info(&pdev->dev, "invalid RTC date, resetting to January 1st, 2013\n");
+               writel(0x130101, pdata->ioaddr + RTC_DATE_REG_OFFS);
+       }
+
        pdata->irq = platform_get_irq(pdev, 0);
 
        platform_set_drvdata(pdev, pdata);