linux-kernel - [PATCH 16/22] Input: max8997_haptic - use guard notation when acquiring mutex

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Message-ID: <20240904044834.1048468-1-dmitry.torokhov@gmail.com>
Date: Tue,  3 Sep 2024 21:48:33 -0700
From: Dmitry Torokhov <dmitry.torokhov@...il.com>
To: linux-input@...r.kernel.org
Cc: Michael Hennerich <michael.hennerich@...log.com>,
	Ville Syrjala <syrjala@....fi>,
	Support Opensource <support.opensource@...semi.com>,
	Eddie James <eajames@...ux.ibm.com>,
	Andrey Moiseev <o2g.org.ru@...il.com>,
	Hans de Goede <hdegoede@...hat.com>,
	Javier Carrasco <javier.carrasco.cruz@...il.com>,
	Jeff LaBundy <jeff@...undy.com>,
	linux-kernel@...r.kernel.org
Subject: [PATCH 16/22] Input: max8997_haptic - use guard notation when acquiring mutex

Using guard notation makes the code more compact and error handling
more robust by ensuring that mutexes are released in all code paths
when control leaves critical section.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@...il.com>
---
 drivers/input/misc/max8997_haptic.c | 15 +++++----------
 1 file changed, 5 insertions(+), 10 deletions(-)

diff --git a/drivers/input/misc/max8997_haptic.c b/drivers/input/misc/max8997_haptic.c
index 11cac4b7dddc..2853455daef2 100644
--- a/drivers/input/misc/max8997_haptic.c
+++ b/drivers/input/misc/max8997_haptic.c
@@ -153,19 +153,19 @@ static void max8997_haptic_enable(struct max8997_haptic *chip)
 {
 	int error;
 
-	mutex_lock(&chip->mutex);
+	guard(mutex)(&chip->mutex);
 
 	error = max8997_haptic_set_duty_cycle(chip);
 	if (error) {
 		dev_err(chip->dev, "set_pwm_cycle failed, error: %d\n", error);
-		goto out;
+		return;
 	}
 
 	if (!chip->enabled) {
 		error = regulator_enable(chip->regulator);
 		if (error) {
 			dev_err(chip->dev, "Failed to enable regulator\n");
-			goto out;
+			return;
 		}
 		max8997_haptic_configure(chip);
 		if (chip->mode == MAX8997_EXTERNAL_MODE) {
@@ -173,19 +173,16 @@ static void max8997_haptic_enable(struct max8997_haptic *chip)
 			if (error) {
 				dev_err(chip->dev, "Failed to enable PWM\n");
 				regulator_disable(chip->regulator);
-				goto out;
+				return;
 			}
 		}
 		chip->enabled = true;
 	}
-
-out:
-	mutex_unlock(&chip->mutex);
 }
 
 static void max8997_haptic_disable(struct max8997_haptic *chip)
 {
-	mutex_lock(&chip->mutex);
+	guard(mutex)(&chip->mutex);
 
 	if (chip->enabled) {
 		chip->enabled = false;
@@ -194,8 +191,6 @@ static void max8997_haptic_disable(struct max8997_haptic *chip)
 			pwm_disable(chip->pwm);
 		regulator_disable(chip->regulator);
 	}
-
-	mutex_unlock(&chip->mutex);
 }
 
 static void max8997_haptic_play_effect_work(struct work_struct *work)
-- 
2.46.0.469.g59c65b2a67-goog