linux-kernel - [PATCH 5/9] rtc: ds1343: use regmap_update

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]

Date:   Sat, 19 Oct 2019 22:49:37 +0200
From:   Alexandre Belloni <alexandre.belloni@...tlin.com>
To:     linux-rtc@...r.kernel.org
Cc:     linux-kernel@...r.kernel.org,
        Alexandre Belloni <alexandre.belloni@...tlin.com>
Subject: [PATCH 5/9] rtc: ds1343: use regmap_update_bits for glitch filter

Use regmap_update_bits to update DS1343_CONTROL_REG in a race free manner
when setting the glitch filter.

Signed-off-by: Alexandre Belloni <alexandre.belloni@...tlin.com>
---
 drivers/rtc/rtc-ds1343.c | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/drivers/rtc/rtc-ds1343.c b/drivers/rtc/rtc-ds1343.c
index ec8d1e82d7ac..7532a2e8407e 100644
--- a/drivers/rtc/rtc-ds1343.c
+++ b/drivers/rtc/rtc-ds1343.c
@@ -108,20 +108,18 @@ static ssize_t ds1343_store_glitchfilter(struct device *dev,
 					const char *buf, size_t count)
 {
 	struct ds1343_priv *priv = dev_get_drvdata(dev->parent);
-	int data;
-
-	regmap_read(priv->map, DS1343_CONTROL_REG, &data);
+	int data = 0;
+	int res;
 
 	if (strncmp(buf, "enabled", 7) == 0)
-		data |= DS1343_EGFIL;
-
-	else if (strncmp(buf, "disabled", 8) == 0)
-		data &= ~(DS1343_EGFIL);
-
-	else
+		data = DS1343_EGFIL;
+	else if (strncmp(buf, "disabled", 8))
 		return -EINVAL;
 
-	regmap_write(priv->map, DS1343_CONTROL_REG, data);
+	res = regmap_update_bits(priv->map, DS1343_CONTROL_REG,
+				 DS1343_EGFIL, data);
+	if (res)
+		return res;
 
 	return count;
 }
-- 
2.21.0