linux-kernel - [PATCH] rtc: ab-eoz9: fix abeoz9_rtc_read

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Message-ID: <20241112150607.3450063-1-alexandre.belloni@bootlin.com>
Date: Tue, 12 Nov 2024 16:06:07 +0100
From: alexandre.belloni@...tlin.com
To: Alexandre Belloni <alexandre.belloni@...tlin.com>
Cc: linux-rtc@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH] rtc: ab-eoz9: fix abeoz9_rtc_read_alarm

From: Alexandre Belloni <alexandre.belloni@...tlin.com>

abeoz9_rtc_read_alarm assumes we always read the alarm in 12-hour mode
while abeoz9_rtc_set_alarm will always set it in 24-hour mode.

We could support 12-hour mode in both functions but it seems very unlikely
that the RTC would be set to 12-hour mode now as the driver has been
setting it to 24-hour mode for a while now. The setting is undefined at
power-up and unchanged by subsequent resets which doesn't help us.

Signed-off-by: Alexandre Belloni <alexandre.belloni@...tlin.com>
---
 drivers/rtc/rtc-ab-eoz9.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/rtc/rtc-ab-eoz9.c b/drivers/rtc/rtc-ab-eoz9.c
index 02f7d0711287..c9448c279ee1 100644
--- a/drivers/rtc/rtc-ab-eoz9.c
+++ b/drivers/rtc/rtc-ab-eoz9.c
@@ -64,7 +64,7 @@
 #define ABEOZ9_BIT_ALARM_MIN		GENMASK(6, 0)
 #define ABEOZ9_REG_ALARM_HOURS		0x12
 #define ABEOZ9_BIT_ALARM_HOURS_PM	BIT(5)
-#define ABEOZ9_BIT_ALARM_HOURS		GENMASK(4, 0)
+#define ABEOZ9_BIT_ALARM_HOURS		GENMASK(5, 0)
 #define ABEOZ9_REG_ALARM_DAYS		0x13
 #define ABEOZ9_BIT_ALARM_DAYS		GENMASK(5, 0)
 #define ABEOZ9_REG_ALARM_WEEKDAYS	0x14
@@ -210,6 +210,7 @@ static int abeoz9_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 	struct abeoz9_rtc_data *data = dev_get_drvdata(dev);
 	struct regmap *regmap = data->regmap;
 	u8 regs[ABEOZ9_ALARM_LEN];
+	unsigned int hour;
 	u8 val[2];
 	int ret;
 
@@ -221,6 +222,10 @@ static int abeoz9_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 	if (ret)
 		return ret;
 
+	ret = regmap_read(regmap, ABEOZ9_REG_HOURS, &hour);
+	if (ret)
+		return ret;
+
 	alarm->enabled = val[0] & ABEOZ9_REG_CTRL_INT_AIE;
 	alarm->pending = val[1] & ABEOZ9_REG_CTRL_INT_FLAG_AF;
 
@@ -231,8 +236,6 @@ static int abeoz9_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 	alarm->time.tm_sec = bcd2bin(FIELD_GET(ABEOZ9_BIT_ALARM_SEC, regs[0]));
 	alarm->time.tm_min = bcd2bin(FIELD_GET(ABEOZ9_BIT_ALARM_MIN, regs[1]));
 	alarm->time.tm_hour = bcd2bin(FIELD_GET(ABEOZ9_BIT_ALARM_HOURS, regs[2]));
-	if (FIELD_GET(ABEOZ9_BIT_ALARM_HOURS_PM, regs[2]))
-		alarm->time.tm_hour += 12;
 
 	alarm->time.tm_mday = bcd2bin(FIELD_GET(ABEOZ9_BIT_ALARM_DAYS, regs[3]));
 
-- 
2.47.0