linux-kernel - [PATCH 06/22] Input: kxtj9 - use guard notation when acquiring mutex/disabling irq

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Message-ID: <20240904044244.1042174-7-dmitry.torokhov@gmail.com>
Date: Tue,  3 Sep 2024 21:42:26 -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 06/22] Input: kxtj9 - use guard notation when acquiring mutex/disabling irq

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

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@...il.com>
---
 drivers/input/misc/kxtj9.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/drivers/input/misc/kxtj9.c b/drivers/input/misc/kxtj9.c
index 837682cb2a7d..c6146bcee9f9 100644
--- a/drivers/input/misc/kxtj9.c
+++ b/drivers/input/misc/kxtj9.c
@@ -314,9 +314,8 @@ static ssize_t kxtj9_set_poll(struct device *dev, struct device_attribute *attr,
 		return error;
 
 	/* Lock the device to prevent races with open/close (and itself) */
-	mutex_lock(&input_dev->mutex);
-
-	disable_irq(client->irq);
+	guard(mutex)(&input_dev->mutex);
+	guard(disable_irq)(&client->irq);
 
 	/*
 	 * Set current interval to the greater of the minimum interval or
@@ -326,9 +325,6 @@ static ssize_t kxtj9_set_poll(struct device *dev, struct device_attribute *attr,
 
 	kxtj9_update_odr(tj9, tj9->last_poll_interval);
 
-	enable_irq(client->irq);
-	mutex_unlock(&input_dev->mutex);
-
 	return count;
 }
 
@@ -504,12 +500,11 @@ static int kxtj9_suspend(struct device *dev)
 	struct kxtj9_data *tj9 = i2c_get_clientdata(client);
 	struct input_dev *input_dev = tj9->input_dev;
 
-	mutex_lock(&input_dev->mutex);
+	guard(mutex)(&input_dev->mutex);
 
 	if (input_device_enabled(input_dev))
 		kxtj9_disable(tj9);
 
-	mutex_unlock(&input_dev->mutex);
 	return 0;
 }
 
@@ -519,12 +514,11 @@ static int kxtj9_resume(struct device *dev)
 	struct kxtj9_data *tj9 = i2c_get_clientdata(client);
 	struct input_dev *input_dev = tj9->input_dev;
 
-	mutex_lock(&input_dev->mutex);
+	guard(mutex)(&input_dev->mutex);
 
 	if (input_device_enabled(input_dev))
 		kxtj9_enable(tj9);
 
-	mutex_unlock(&input_dev->mutex);
 	return 0;
 }
 
-- 
2.46.0.469.g59c65b2a67-goog