linux-kernel - [PATCH v3 05/10] gpio: swnode: allow referencing GPIO chips by firmware nodes

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Message-Id: <20251029-reset-gpios-swnodes-v3-5-638a4cb33201@linaro.org>
Date: Wed, 29 Oct 2025 13:28:39 +0100
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 v3 05/10] gpio: swnode: allow referencing GPIO chips by
 firmware nodes

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

When doing a software node lookup, we require both the fwnode that
references a GPIO chip as well as the node associated with that chip to
be software nodes. However, we now allow referencing generic firmware
nodes from software nodes in driver core so we should allow the same in
GPIO core. Make the software node name check optional and dependent on
whether the referenced firmware node is a software node. If it's not,
just continue with the lookup.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
---
 drivers/gpio/gpiolib-swnode.c | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/drivers/gpio/gpiolib-swnode.c b/drivers/gpio/gpiolib-swnode.c
index e3806db1c0e077d76fcc71a50ca40bbf6872ca40..16af83fcc5aa886dd009dedc26b1ac23e5cbc4ea 100644
--- a/drivers/gpio/gpiolib-swnode.c
+++ b/drivers/gpio/gpiolib-swnode.c
@@ -30,16 +30,15 @@ static struct gpio_device *swnode_get_gpio_device(struct fwnode_handle *fwnode)
 	struct gpio_device *gdev;

 	gdev_node = to_software_node(fwnode);
-	if (!gdev_node || !gdev_node->name)
-		return ERR_PTR(-EINVAL);
-
-	/*
-	 * 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))
-		return ERR_PTR(-ENOENT);
+	if (gdev_node && gdev_node->name) {
+		/*
+		 * 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))
+			return ERR_PTR(-ENOENT);
+	}

 	gdev = gpio_device_find_by_fwnode(fwnode);
 	return gdev ?: ERR_PTR(-EPROBE_DEFER);

-- 
2.48.1