linux-kernel - [PATCH 2/8] gpio: mxc: use lock guards for the generic GPIO chip lock

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Message-Id: <20250624-gpio-mmio-rework-v1-2-aea12209d258@linaro.org>
Date: Tue, 24 Jun 2025 15:27:34 +0200
From: Bartosz Golaszewski <brgl@...ev.pl>
To: Linus Walleij <linus.walleij@...aro.org>, 
 Bartosz Golaszewski <brgl@...ev.pl>, Shawn Guo <shawnguo@...nel.org>, 
 Sascha Hauer <s.hauer@...gutronix.de>, 
 Pengutronix Kernel Team <kernel@...gutronix.de>, 
 Fabio Estevam <festevam@...il.com>
Cc: linux-kernel@...r.kernel.org, linux-gpio@...r.kernel.org, 
 imx@...ts.linux.dev, linux-arm-kernel@...ts.infradead.org, 
 Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
Subject: [PATCH 2/8] gpio: mxc: use lock guards for the generic GPIO chip
 lock

From: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>

Simplify the code by using lock guards for the bgpio_lock.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
---
 drivers/gpio/gpio-mxc.c | 50 ++++++++++++++++++++++---------------------------
 1 file changed, 22 insertions(+), 28 deletions(-)

diff --git a/drivers/gpio/gpio-mxc.c b/drivers/gpio/gpio-mxc.c
index 4af5a2972d12f68909dd87d9396921c80445f87c..1c37168c8d0a657d7f93067d9ac95cfbd821f757 100644
--- a/drivers/gpio/gpio-mxc.c
+++ b/drivers/gpio/gpio-mxc.c
@@ -7,6 +7,7 @@
 // Authors: Daniel Mack, Juergen Beisert.
 // Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
 
+#include <linux/cleanup.h>
 #include <linux/clk.h>
 #include <linux/err.h>
 #include <linux/init.h>
@@ -161,7 +162,6 @@ static int gpio_set_irq_type(struct irq_data *d, u32 type)
 {
 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 	struct mxc_gpio_port *port = gc->private;
-	unsigned long flags;
 	u32 bit, val;
 	u32 gpio_idx = d->hwirq;
 	int edge;
@@ -200,41 +200,38 @@ static int gpio_set_irq_type(struct irq_data *d, u32 type)
 		return -EINVAL;
 	}
 
-	raw_spin_lock_irqsave(&port->gc.bgpio_lock, flags);
+	scoped_guard(raw_spinlock_irqsave, &port->gc.bgpio_lock) {
+		if (GPIO_EDGE_SEL >= 0) {
+			val = readl(port->base + GPIO_EDGE_SEL);
+			if (edge == GPIO_INT_BOTH_EDGES)
+				writel(val | (1 << gpio_idx),
+				       port->base + GPIO_EDGE_SEL);
+			else
+				writel(val & ~(1 << gpio_idx),
+				       port->base + GPIO_EDGE_SEL);
+		}
 
-	if (GPIO_EDGE_SEL >= 0) {
-		val = readl(port->base + GPIO_EDGE_SEL);
-		if (edge == GPIO_INT_BOTH_EDGES)
-			writel(val | (1 << gpio_idx),
-				port->base + GPIO_EDGE_SEL);
-		else
-			writel(val & ~(1 << gpio_idx),
-				port->base + GPIO_EDGE_SEL);
+		if (edge != GPIO_INT_BOTH_EDGES) {
+			reg += GPIO_ICR1 + ((gpio_idx & 0x10) >> 2); /* lower or upper register */
+			bit = gpio_idx & 0xf;
+			val = readl(reg) & ~(0x3 << (bit << 1));
+			writel(val | (edge << (bit << 1)), reg);
+		}
+
+		writel(1 << gpio_idx, port->base + GPIO_ISR);
+		port->pad_type[gpio_idx] = type;
 	}
 
-	if (edge != GPIO_INT_BOTH_EDGES) {
-		reg += GPIO_ICR1 + ((gpio_idx & 0x10) >> 2); /* lower or upper register */
-		bit = gpio_idx & 0xf;
-		val = readl(reg) & ~(0x3 << (bit << 1));
-		writel(val | (edge << (bit << 1)), reg);
-	}
-
-	writel(1 << gpio_idx, port->base + GPIO_ISR);
-	port->pad_type[gpio_idx] = type;
-
-	raw_spin_unlock_irqrestore(&port->gc.bgpio_lock, flags);
-
 	return port->gc.direction_input(&port->gc, gpio_idx);
 }
 
 static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio)
 {
 	void __iomem *reg = port->base;
-	unsigned long flags;
 	u32 bit, val;
 	int edge;
 
-	raw_spin_lock_irqsave(&port->gc.bgpio_lock, flags);
+	guard(raw_spinlock_irqsave)(&port->gc.bgpio_lock);
 
 	reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */
 	bit = gpio & 0xf;
@@ -250,12 +247,9 @@ static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio)
 	} else {
 		pr_err("mxc: invalid configuration for GPIO %d: %x\n",
 		       gpio, edge);
-		goto unlock;
+		return;
 	}
 	writel(val | (edge << (bit << 1)), reg);
-
-unlock:
-	raw_spin_unlock_irqrestore(&port->gc.bgpio_lock, flags);
 }
 
 /* handle 32 interrupts in one status register */

-- 
2.48.1