From bb58da08f01ee12561867fcd4385b82679ae7f6c Mon Sep 17 00:00:00 2001 From: Andreas Dumberger Date: Thu, 12 Apr 2012 12:49:12 -0700 Subject: [PATCH] drivers/rtc/rtc-r9701.c: reset registers if invalid values are detected hwclock refuses to set date/time if RTC registers contain invalid values. Check the date/time register values at probe time and initialize them to make hwclock happy. Signed-off-by: Andreas Dumberger Signed-off-by: Anatolij Gustschin Cc: Alessandro Zummo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rtc/rtc-r9701.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) 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)) -- 2.30.2