linux-kernel - [PATCH 4/9] gpio: swnode: don't use the swnode's name as the key for GPIO lookup

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Message-Id: <20251006-reset-gpios-swnodes-v1-4-6d3325b9af42@linaro.org>
Date: Mon, 06 Oct 2025 15:00:19 +0200
From: Bartosz Golaszewski <brgl@...ev.pl>
To: Linus Walleij <linus.walleij@...aro.org>, 
 Bartosz Golaszewski <brgl@...ev.pl>, 
 Andy Shevchenko <andriy.shevchenko@...ux.intel.com>, 
 Daniel Scally <djrscally@...il.com>, 
 Heikki Krogerus <heikki.krogerus@...ux.intel.com>, 
 Sakari Ailus <sakari.ailus@...ux.intel.com>, 
 Greg Kroah-Hartman <gregkh@...uxfoundation.org>, 
 "Rafael J. Wysocki" <rafael@...nel.org>, Danilo Krummrich <dakr@...nel.org>, 
 Philipp Zabel <p.zabel@...gutronix.de>, 
 Krzysztof Kozlowski <krzk@...nel.org>
Cc: linux-gpio@...r.kernel.org, linux-kernel@...r.kernel.org, 
 linux-acpi@...r.kernel.org, 
 Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
Subject: [PATCH 4/9] gpio: swnode: don't use the swnode's name as the key
 for GPIO lookup

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

Looking up a GPIO controller by label that is the name of the software
node is wonky at best - the GPIO controller driver is free to set
a different label than the name of its firmware node. We're already being
passed a firmware node handle attached to the GPIO device to
swnode_get_gpio_device() so use it instead for a more precise lookup.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
---
 drivers/gpio/gpiolib-swnode.c | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/drivers/gpio/gpiolib-swnode.c b/drivers/gpio/gpiolib-swnode.c
index f21dbc28cf2c8c2d06d034b7c89d302cc52bb9b5..573b5216cfda105bafa58e04fc5ad3a38d283698 100644
--- a/drivers/gpio/gpiolib-swnode.c
+++ b/drivers/gpio/gpiolib-swnode.c
@@ -7,6 +7,7 @@

 #define pr_fmt(fmt) "gpiolib: swnode: " fmt

+#include <linux/cleanup.h>
 #include <linux/err.h>
 #include <linux/errno.h>
 #include <linux/export.h>
@@ -26,23 +27,20 @@

 static struct gpio_device *swnode_get_gpio_device(struct fwnode_handle *fwnode)
 {
-	const struct software_node *gdev_node;
-	struct gpio_device *gdev;
-
-	gdev_node = to_software_node(fwnode);
-	if (!gdev_node || !gdev_node->name)
-		return ERR_PTR(-EINVAL);
+	struct gpio_device *gdev __free(gpio_device_put) =
+					gpio_device_find_by_fwnode(fwnode);
+	if (!gdev)
+		return ERR_PTR(-EPROBE_DEFER);

 	/*
 	 * Check for a special node that identifies undefined GPIOs, this is
 	 * primarily used as a key for internal chip selects in SPI bindings.
 	 */
 	if (IS_ENABLED(CONFIG_GPIO_SWNODE_UNDEFINED) &&
-	    !strcmp(gdev_node->name, GPIOLIB_SWNODE_UNDEFINED_NAME))
+	    !strcmp(fwnode_get_name(fwnode), GPIOLIB_SWNODE_UNDEFINED_NAME))
 		return ERR_PTR(-ENOENT);

-	gdev = gpio_device_find_by_label(gdev_node->name);
-	return gdev ?: ERR_PTR(-EPROBE_DEFER);
+	return no_free_ptr(gdev);
 }

 static int swnode_gpio_get_reference(const struct fwnode_handle *fwnode,

-- 
2.48.1