linux-kernel - [PATCH 6/6] rtc: rv8803: Clear V1F when setting the time

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1469097692-103146-6-git-send-email-benoit@wsystem.com>
Date:	Thu, 21 Jul 2016 12:41:32 +0200
From:	Benoît Thébaudeau <benoit@...stem.com>
To:	rtc-linux@...glegroups.com
Cc:	linux-kernel@...r.kernel.org,
	Alessandro Zummo <a.zummo@...ertech.it>,
	Alexandre Belloni <alexandre.belloni@...e-electrons.com>,
	Benoît Thébaudeau <benoit@...stem.com>
Subject: [PATCH 6/6] rtc: rv8803: Clear V1F when setting the time

V1F indicates that the time accuracy may have been compromised because
of a voltage drop (possibly only temporary) below VLOW1, which stops the
temperature compensation. When the time is set, the accuracy is
restored, so V1F should be cleared in order to indicate this and to be
able to detect the next temperature compensation loss. This is the same
principle as for V2F, which is cleared when the time is set to indicate
that the time is no longer invalid and to be able to detect the next
data loss.

Signed-off-by: Benoît Thébaudeau <benoit@...stem.com>
---
 drivers/rtc/rtc-rv8803.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/rtc/rtc-rv8803.c b/drivers/rtc/rtc-rv8803.c
index 24c688e..9a2f6a9 100644
--- a/drivers/rtc/rtc-rv8803.c
+++ b/drivers/rtc/rtc-rv8803.c
@@ -265,7 +265,7 @@ static int rv8803_set_time(struct device *dev, struct rtc_time *tm)
 	}

 	ret = rv8803_write_reg(rv8803->client, RV8803_FLAG,
-			       flags & ~RV8803_FLAG_V2F);
+			       flags & ~(RV8803_FLAG_V1F | RV8803_FLAG_V2F));

 	mutex_unlock(&rv8803->flags_lock);

-- 
2.5.0