linux-kernel - [PATCH 4.19 177/639] rtc: ds1307: rx8130: Fix alarm handling

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Message-Id: <20200124093109.349854130@linuxfoundation.org>
Date:   Fri, 24 Jan 2020 10:25:47 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        Uwe Kleine-König 
        <u.kleine-koenig@...gutronix.de>,
        Alexandre Belloni <alexandre.belloni@...tlin.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 4.19 177/639] rtc: ds1307: rx8130: Fix alarm handling

From: Uwe Kleine-König <u.kleine-koenig@...gutronix.de>

[ Upstream commit 3f929cad943380370b6db31fcb7a38d898d91089 ]

When the EXTENSION.WADA bit is set, register 0x19 contains a bitmap of
week days, not a day of month. As Linux only handles a single alarm
without repetition using day of month is more flexible, so clear this
bit. (Otherwise a value depending on time.tm_wday would have to be
written to register 0x19.)

Also optimize setting the AIE bit to use a single register write instead
of a bulk write of three registers.

Fixes: ee0981be7704 ("rtc: ds1307: Add support for Epson RX8130CE")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@...gutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@...tlin.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/rtc/rtc-ds1307.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
index 71396b62dc52b..ebd59e86a567b 100644
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -749,8 +749,8 @@ static int rx8130_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 	if (ret < 0)
 		return ret;
 
-	ctl[0] &= ~RX8130_REG_EXTENSION_WADA;
-	ctl[1] |= RX8130_REG_FLAG_AF;
+	ctl[0] &= RX8130_REG_EXTENSION_WADA;
+	ctl[1] &= ~RX8130_REG_FLAG_AF;
 	ctl[2] &= ~RX8130_REG_CONTROL0_AIE;
 
 	ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
@@ -773,8 +773,7 @@ static int rx8130_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 
 	ctl[2] |= RX8130_REG_CONTROL0_AIE;
 
-	return regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
-				 sizeof(ctl));
+	return regmap_write(ds1307->regmap, RX8130_REG_CONTROL0, ctl[2]);
 }
 
 static int rx8130_alarm_irq_enable(struct device *dev, unsigned int enabled)
-- 
2.20.1