linux-kernel - [PATCH 1/2] rtc: max31335: remove unecessary locking

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Message-ID: <20240115232215.273374-1-alexandre.belloni@bootlin.com>
Date: Tue, 16 Jan 2024 00:22:13 +0100
From: alexandre.belloni@...tlin.com
To: Antoniu Miclaus <antoniu.miclaus@...log.com>,
	Alexandre Belloni <alexandre.belloni@...tlin.com>
Cc: linux-rtc@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH 1/2] rtc: max31335: remove unecessary locking

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

There is no race condition when accessing MAX31335_STATUS1 because it is
always about clearing the alarm interrupt bit.

Signed-off-by: Alexandre Belloni <alexandre.belloni@...tlin.com>
---
 drivers/rtc/rtc-max31335.c | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/drivers/rtc/rtc-max31335.c b/drivers/rtc/rtc-max31335.c
index 3ddfe71bbb56..2ce23f60a7f3 100644
--- a/drivers/rtc/rtc-max31335.c
+++ b/drivers/rtc/rtc-max31335.c
@@ -348,27 +348,19 @@ static int max31335_alarm_irq_enable(struct device *dev, unsigned int enabled)
 static irqreturn_t max31335_handle_irq(int irq, void *dev_id)
 {
 	struct max31335_data *max31335 = dev_id;
-	struct mutex *lock = &max31335->rtc->ops_lock;
 	int ret, status;
 
-	mutex_lock(lock);
-
 	ret = regmap_read(max31335->regmap, MAX31335_STATUS1, &status);
 	if (ret)
-		goto exit;
+		return IRQ_HANDLED;
 
 	if (FIELD_GET(MAX31335_STATUS1_A1F, status)) {
-		ret = regmap_update_bits(max31335->regmap, MAX31335_STATUS1,
-					 MAX31335_STATUS1_A1F, 0);
-		if (ret)
-			goto exit;
+		regmap_update_bits(max31335->regmap, MAX31335_STATUS1,
+				   MAX31335_STATUS1_A1F, 0);
 
 		rtc_update_irq(max31335->rtc, 1, RTC_AF | RTC_IRQF);
 	}
 
-exit:
-	mutex_unlock(lock);
-
 	return IRQ_HANDLED;
 }
 
-- 
2.43.0