linux-kernel - [PATCH 11/17] Input: matrix_keypad - use guard notation when acquiring spinlock

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Message-ID: <20240825051627.2848495-12-dmitry.torokhov@gmail.com>
Date: Sat, 24 Aug 2024 22:16:15 -0700
From: Dmitry Torokhov <dmitry.torokhov@...il.com>
To: linux-input@...r.kernel.org
Cc: Michael Hennerich <michael.hennerich@...log.com>,
	Shawn Guo <shawnguo@...nel.org>,
	Sascha Hauer <s.hauer@...gutronix.de>,
	Fabio Estevam <festevam@...il.com>,
	Laxman Dewangan <ldewangan@...dia.com>,
	Thierry Reding <thierry.reding@...il.com>,
	Hans de Goede <hdegoede@...hat.com>,
	Tony Lindgren <tony@...mide.com>,
	Jeff LaBundy <jeff@...undy.com>,
	linux-kernel@...r.kernel.org,
	imx@...ts.linux.dev,
	linux-arm-kernel@...ts.infradead.org,
	linux-tegra@...r.kernel.org
Subject: [PATCH 11/17] Input: matrix_keypad - use guard notation when acquiring spinlock

This makes the code more compact and error handling more robust
by ensuring that locks are released in all code paths when control
leaves critical section.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@...il.com>
---
 drivers/input/keyboard/matrix_keypad.c | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c
index 7a56f3d3aacd..bd763d704306 100644
--- a/drivers/input/keyboard/matrix_keypad.c
+++ b/drivers/input/keyboard/matrix_keypad.c
@@ -158,18 +158,17 @@ static void matrix_keypad_scan(struct work_struct *work)
 	activate_all_cols(pdata, true);
 
 	/* Enable IRQs again */
-	spin_lock_irq(&keypad->lock);
-	keypad->scan_pending = false;
-	enable_row_irqs(keypad);
-	spin_unlock_irq(&keypad->lock);
+	scoped_guard(spinlock_irq, &keypad->lock) {
+		keypad->scan_pending = false;
+		enable_row_irqs(keypad);
+	}
 }
 
 static irqreturn_t matrix_keypad_interrupt(int irq, void *id)
 {
 	struct matrix_keypad *keypad = id;
-	unsigned long flags;
 
-	spin_lock_irqsave(&keypad->lock, flags);
+	guard(spinlock_irqsave)(&keypad->lock);
 
 	/*
 	 * See if another IRQ beaten us to it and scheduled the
@@ -185,7 +184,6 @@ static irqreturn_t matrix_keypad_interrupt(int irq, void *id)
 		msecs_to_jiffies(keypad->pdata->debounce_ms));
 
 out:
-	spin_unlock_irqrestore(&keypad->lock, flags);
 	return IRQ_HANDLED;
 }
 
@@ -209,9 +207,9 @@ static void matrix_keypad_stop(struct input_dev *dev)
 {
 	struct matrix_keypad *keypad = input_get_drvdata(dev);
 
-	spin_lock_irq(&keypad->lock);
-	keypad->stopped = true;
-	spin_unlock_irq(&keypad->lock);
+	scoped_guard(spinlock_irq, &keypad->lock) {
+		keypad->stopped = true;
+	}
 
 	flush_delayed_work(&keypad->work);
 	/*
-- 
2.46.0.295.g3b9ea8a38a-goog