From 7fd17ce98fb333003ece62ab16e873062ee64d14 Mon Sep 17 00:00:00 2001 From: Joakim Tjernlund Date: Tue, 29 Jun 2010 15:05:34 -0700 Subject: [PATCH] rtc: fix ds1388 time corruption commit 96fc3a45ea073136566f3c2676cad52f8b39a7df upstream. The ds1307 driver misreads the ds1388 registers when checking for 12 or 24 hour mode. Instead of checking the hour register it reads the minute register. Therefore the driver thinks minutes >= 40 has the 12HR bit set and resets the minute register by zeroing the high bits. This results in minutes are reset to 0-9, jumping back in time 40 or 50 minutes. The time jump is also written back to the RTC. Signed-off-by: Joakim Tjernlund Cc: Wan ZongShun Cc: Alessandro Zummo Cc: Paul Gortmaker Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- drivers/rtc/rtc-ds1307.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c index c4ec5c158aa1..a01bbe22a2f8 100644 --- a/drivers/rtc/rtc-ds1307.c +++ b/drivers/rtc/rtc-ds1307.c @@ -775,7 +775,7 @@ static int __devinit ds1307_probe(struct i2c_client *client, read_rtc: /* read RTC registers */ - tmp = ds1307->read_block_data(ds1307->client, 0, 8, buf); + tmp = ds1307->read_block_data(ds1307->client, ds1307->offset, 8, buf); if (tmp != 8) { pr_debug("read error %d\n", tmp); err = -EIO; @@ -860,7 +860,7 @@ read_rtc: if (ds1307->regs[DS1307_REG_HOUR] & DS1307_BIT_PM) tmp += 12; i2c_smbus_write_byte_data(client, - DS1307_REG_HOUR, + ds1307->offset + DS1307_REG_HOUR, bin2bcd(tmp)); } -- 2.39.5