[PATCH v2 0/2] w5100: restore GPIO-based link detection

[PATCH v2 0/2] w5100: restore GPIO-based link detection

[Arthur Crépin Leblond]

Hi,

I am using the W5500 on a Raspberry Pi and rely on the link GPIO for
the carrier detection.
If we could bring it back, I would greatly appreciate.

Thank you!

Arthur Crépin Leblond

Signed-off-by: Arthur Crépin Leblond <arthur@marmottus.net>
---
Changes in v2:
- Convert device tree binding to YAML
- Use devm_request_threaded_irq instead of request_any_context_irq
- Use devm_gpiod_get_optional instead of gpiod_get_optional
- Call dev_err_probe on gpiod_to_irq failure
- Remove link_irq from priv
- Use a fixed string for the IRQ name
- Remove empty new lines
- Link to v1: https://patch.msgid.link/20260804-wiznet-link-gpio-v1-1-b626fd4f7ccb@marmottus.net
---
Arthur Crépin Leblond (2):
      w5100: restore GPIO-based link detection
      dt-bindings: net: convert wiznet,w5x00 to YAML

 .../devicetree/bindings/net/wiznet,w5x00.txt       |  50 ----------
 .../devicetree/bindings/net/wiznet,w5x00.yaml      | 103 +++++++++++++++++++++
 drivers/net/ethernet/wiznet/w5100.c                |  71 ++++++++++++++
 3 files changed, 174 insertions(+), 50 deletions(-)

[PATCH v2 1/2] w5100: restore GPIO-based link detection

[Arthur Crépin Leblond]

Commit dacf281771a9 ("w5100: remove unused gpio link detection")
dropped the link_gpio/link_irq handling on the grounds that no
devicetree user passed a "link" GPIO at the time.

This isn't a plain revert of that removal. The link GPIO is now
bound from the device tree link-gpios property using the resource
managed GPIO descriptors.

The link IRQ is also requested with devm_request_threaded_irq()
instead of request_any_context_irq(), so it is released automatically
on driver removal or probe failure.

Signed-off-by: Arthur Crépin Leblond <arthur@marmottus.net>
---
 drivers/net/ethernet/wiznet/w5100.c | 71 +++++++++++++++++++++++++++++++++++++
 1 file changed, 71 insertions(+)

diff --git a/drivers/net/ethernet/wiznet/w5100.c b/drivers/net/ethernet/wiznet/w5100.c
index 53d8dc642fbd..1410a9fcfa92 100644
--- a/drivers/net/ethernet/wiznet/w5100.c
+++ b/drivers/net/ethernet/wiznet/w5100.c
@@ -22,6 +22,7 @@
 #include <linux/ioport.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
+#include <linux/gpio/consumer.h>
 
 #include "w5100.h"
 
@@ -154,6 +155,7 @@ struct w5100_priv {
 	u16 s0_rx_buf_size;
 
 	int irq;
+	struct gpio_desc *link_gpio;
 
 	struct napi_struct napi;
 	struct net_device *ndev;
@@ -414,6 +416,16 @@ static void w5100_get_drvinfo(struct net_device *ndev,
 		sizeof(info->bus_info));
 }
 
+static u32 w5100_get_link(struct net_device *ndev)
+{
+	struct w5100_priv *priv = netdev_priv(ndev);
+
+	if (priv->link_gpio)
+		return !!gpiod_get_value_cansleep(priv->link_gpio);
+
+	return 1;
+}
+
 static u32 w5100_get_msglevel(struct net_device *ndev)
 {
 	struct w5100_priv *priv = netdev_priv(ndev);
@@ -616,6 +628,24 @@ static irqreturn_t w5100_interrupt(int irq, void *ndev_instance)
 	return IRQ_HANDLED;
 }
 
+static irqreturn_t w5100_detect_link(int irq, void *ndev_instance)
+{
+	struct net_device *ndev = ndev_instance;
+	struct w5100_priv *priv = netdev_priv(ndev);
+
+	if (netif_running(ndev)) {
+		if (gpiod_get_value(priv->link_gpio) != 0) {
+			netif_info(priv, link, ndev, "link is up\n");
+			netif_carrier_on(ndev);
+		} else {
+			netif_info(priv, link, ndev, "link is down\n");
+			netif_carrier_off(ndev);
+		}
+	}
+
+	return IRQ_HANDLED;
+}
+
 static void w5100_setrx_work(struct work_struct *work)
 {
 	struct w5100_priv *priv = container_of(work, struct w5100_priv,
@@ -659,6 +689,14 @@ static int w5100_open(struct net_device *ndev)
 	w5100_hw_start(priv);
 	napi_enable(&priv->napi);
 	netif_start_queue(ndev);
+
+	if (priv->link_gpio) {
+		if (gpiod_get_value_cansleep(priv->link_gpio) != 0)
+			netif_carrier_on(ndev);
+		else
+			netif_carrier_off(ndev);
+	}
+
 	return 0;
 }
 
@@ -678,6 +716,7 @@ static const struct ethtool_ops w5100_ethtool_ops = {
 	.get_drvinfo		= w5100_get_drvinfo,
 	.get_msglevel		= w5100_get_msglevel,
 	.set_msglevel		= w5100_set_msglevel,
+	.get_link		= w5100_get_link,
 	.get_regs_len		= w5100_get_regs_len,
 	.get_regs		= w5100_get_regs,
 };
@@ -751,6 +790,13 @@ int w5100_probe(struct device *dev, const struct w5100_ops *ops,
 	priv->ndev = ndev;
 	priv->ops = ops;
 	priv->irq = irq;
+	priv->link_gpio = devm_gpiod_get_optional(dev, "link", GPIOD_IN);
+	if (IS_ERR(priv->link_gpio)) {
+		err = dev_err_probe(dev, PTR_ERR(priv->link_gpio),
+				    "failed to get link GPIO\n");
+		priv->link_gpio = NULL;
+		goto err_register;
+	}
 
 	ndev->netdev_ops = &w5100_netdev_ops;
 	ndev->ethtool_ops = &w5100_ethtool_ops;
@@ -803,8 +849,29 @@ int w5100_probe(struct device *dev, const struct w5100_ops *ops,
 	if (err)
 		goto err_hw;
 
+	if (priv->link_gpio) {
+		int link_irq = gpiod_to_irq(priv->link_gpio);
+
+		if (link_irq < 0) {
+			err = dev_err_probe(dev, link_irq,
+					    "No corresponding irq for link gpio\n");
+			goto err_gpio;
+		}
+
+		err = devm_request_threaded_irq(dev, link_irq, NULL,
+						w5100_detect_link,
+						IRQF_TRIGGER_RISING |
+						IRQF_TRIGGER_FALLING |
+						IRQF_ONESHOT,
+						"w5100-link", priv->ndev);
+		if (err < 0)
+			goto err_gpio;
+	}
+
 	return 0;
 
+err_gpio:
+	free_irq(priv->irq, ndev);
 err_hw:
 	destroy_workqueue(priv->xfer_wq);
 err_wq:
@@ -857,6 +924,10 @@ static int w5100_resume(struct device *dev)
 		w5100_hw_start(priv);
 
 		netif_device_attach(ndev);
+
+		if (!priv->link_gpio ||
+		    gpiod_get_value_cansleep(priv->link_gpio) != 0)
+			netif_carrier_on(ndev);
 	}
 	return 0;
 }

-- 
2.55.0

[PATCH v2 2/2] dt-bindings: net: convert wiznet,w5x00 to YAML

[Arthur Crépin Leblond]

Convert the Wiznet w5x00 SPI Ethernet controller binding from
text to DT schema format.

Signed-off-by: Arthur Crépin Leblond <arthur@marmottus.net>
---
 .../devicetree/bindings/net/wiznet,w5x00.txt       |  50 ----------
 .../devicetree/bindings/net/wiznet,w5x00.yaml      | 103 +++++++++++++++++++++
 2 files changed, 103 insertions(+), 50 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/wiznet,w5x00.txt b/Documentation/devicetree/bindings/net/wiznet,w5x00.txt
deleted file mode 100644
index e9665798c4be..000000000000
--- a/Documentation/devicetree/bindings/net/wiznet,w5x00.txt
+++ /dev/null
@@ -1,50 +0,0 @@
-* Wiznet w5x00
-
-This is a standalone 10/100 MBit Ethernet controller with SPI interface.
-
-For each device connected to a SPI bus, define a child node within
-the SPI master node.
-
-Required properties:
-- compatible: Should be one of the following strings:
-	      "wiznet,w5100"
-	      "wiznet,w5200"
-	      "wiznet,w5500"
-- reg: Specify the SPI chip select the chip is wired to.
-- interrupts: Specify the interrupt index within the interrupt controller (referred
-              to above in interrupt-parent) and interrupt type. w5x00 natively
-              generates falling edge interrupts, however, additional board logic
-              might invert the signal.
-- pinctrl-names: List of assigned state names, see pinctrl binding documentation.
-- pinctrl-0: List of phandles to configure the GPIO pin used as interrupt line,
-             see also generic and your platform specific pinctrl binding
-             documentation.
-
-Optional properties:
-- spi-max-frequency: Maximum frequency of the SPI bus when accessing the w5500.
-  According to the w5500 datasheet, the chip allows a maximum of 80 MHz, however,
-  board designs may need to limit this value.
-- local-mac-address: See ethernet.txt in the same directory.
-
-
-Example (for Raspberry Pi with pin control stuff for GPIO irq):
-
-&spi {
-	ethernet@0: w5500@0 {
-		compatible = "wiznet,w5500";
-		reg = <0>;
-		pinctrl-names = "default";
-		pinctrl-0 = <&eth1_pins>;
-		interrupt-parent = <&gpio>;
-		interrupts = <25 IRQ_TYPE_EDGE_FALLING>;
-		spi-max-frequency = <30000000>;
-	};
-};
-
-&gpio {
-	eth1_pins: eth1_pins {
-		brcm,pins = <25>;
-		brcm,function = <0>; /* in */
-		brcm,pull = <0>; /* none */
-	};
-};
diff --git a/Documentation/devicetree/bindings/net/wiznet,w5x00.yaml b/Documentation/devicetree/bindings/net/wiznet,w5x00.yaml
new file mode 100644
index 000000000000..8f45a5d773fe
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/wiznet,w5x00.yaml
@@ -0,0 +1,103 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/wiznet,w5x00.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Wiznet w5x00 SPI Ethernet Controller
+
+description: |
+  This is a standalone 10/100 MBit Ethernet controller with SPI interface.
+
+  For each device connected to a SPI bus, define a child node within the SPI master node.
+
+allOf:
+  - $ref: /schemas/net/ethernet-controller.yaml#
+  - $ref: /schemas/spi/spi-peripheral-props.yaml#
+
+properties:
+  compatible:
+    enum:
+      - wiznet,w5100
+      - wiznet,w5200
+      - wiznet,w5500
+
+  reg:
+    description: Specify the SPI chip select the chip is wired to.
+    maxItems: 1
+    minItems: 1
+
+  interrupts:
+    description:
+      Specify the interrupt index within the interrupt controller (referred to
+      above in interrupt-parent) and interrupt type. w5x00 natively generates
+      falling edge interrupts, however, additional board logic might invert the
+      signal.
+    maxItems: 1
+    minItems: 1
+
+  pinctrl-names:
+    description:
+      List of assigned state names, see pinctrl binding documentation.
+    enum:
+      - default
+    minItems: 1
+
+  pinctrl-0:
+    description:
+      List of phandles to configure the GPIO pin used as interrupt line, see
+      also generic and your platform specific pinctrl binding documentation.
+    minItems: 1
+
+  local-mac-address: true
+
+  spi-max-frequency:
+    description:
+      Maximum frequency of the SPI bus when accessing the w5500. According to
+      the w5500 datasheet, the chip allows a maximum of 80 MHz, however, board
+      designs may need to limit this value.
+    maximum: 80000000
+
+  link-gpios:
+    description: A GPIO line used for the link detection interrupt.
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - pinctrl-names
+  - pinctrl-0
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    /* Example (for Raspberry Pi with pin control stuff for GPIO irq) */
+
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        ethernet@0: w5500@0 {
+          compatible = "wiznet,w5500";
+            reg = <0>;
+            pinctrl-names = "default";
+            pinctrl-0 = <&eth1_pins>;
+            interrupt-parent = <&gpio>;
+            interrupts = <25 IRQ_TYPE_EDGE_FALLING>;
+            spi-max-frequency = <30000000>;
+            link-gpios = <&gpio 4 GPIO_ACTIVE_HIGH>;
+            local-mac-address = [ a0 b0 c0 d0 e0 f0 ];
+        };
+    };
+
+    &gpio {
+      eth1_pins: eth1_pins {
+        brcm,pins = <25 4>;
+        brcm,function = <0 0>; /* in */
+        brcm,pull = <0 0>; /* none */
+    };

-- 
2.55.0

Re: [PATCH v2 1/2] w5100: restore GPIO-based link detection

[Arnd Bergmann]

On Tue, Aug 4, 2026, at 19:40, Arthur Crépin Leblond wrote:
> Commit dacf281771a9 ("w5100: remove unused gpio link detection")
> dropped the link_gpio/link_irq handling on the grounds that no
> devicetree user passed a "link" GPIO at the time.
>
> This isn't a plain revert of that removal. The link GPIO is now
> bound from the device tree link-gpios property using the resource
> managed GPIO descriptors.
>
> The link IRQ is also requested with devm_request_threaded_irq()
> instead of request_any_context_irq(), so it is released automatically
> on driver removal or probe failure.
>
> Signed-off-by: Arthur Crépin Leblond <arthur@marmottus.net>

Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Re: [PATCH v2 2/2] dt-bindings: net: convert wiznet,w5x00 to YAML

[Rob Herring (Arm)]

On Tue, 04 Aug 2026 19:40:57 +0200, Arthur Crépin Leblond wrote:
> Convert the Wiznet w5x00 SPI Ethernet controller binding from
> text to DT schema format.
> 
> Signed-off-by: Arthur Crépin Leblond <arthur@marmottus.net>
> ---
>  .../devicetree/bindings/net/wiznet,w5x00.txt       |  50 ----------
>  .../devicetree/bindings/net/wiznet,w5x00.yaml      | 103 +++++++++++++++++++++
>  2 files changed, 103 insertions(+), 50 deletions(-)
> 

My bot found errors running 'make dt_binding_check' on your patch:

yamllint warnings/errors:

dtschema/dtc warnings/errors:
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/net/wiznet,w5x00.yaml: properties:pinctrl-names: 'enum' should not be valid under {'enum': ['const', 'enum', 'exclusiveMaximum', 'exclusiveMinimum', 'minimum', 'maximum', 'multipleOf', 'pattern']}
	hint: Scalar and array keywords cannot be mixed
	from schema $id: http://devicetree.org/meta-schemas/keywords.yaml
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/net/wiznet,w5x00.yaml: 'maintainers' is a required property
	hint: Metaschema for devicetree binding documentation
	from schema $id: http://devicetree.org/meta-schemas/base.yaml
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/net/wiznet,w5x00.yaml: properties:reg: 'anyOf' conditional failed, one must be fixed:
	'minItems' is not one of ['maxItems', 'description', 'deprecated']
		hint: Only "maxItems" is required for a single entry if there are no constraints defined for the values.
	'maxItems' is not one of ['description', 'deprecated', 'const', 'enum', 'minimum', 'maximum', 'multipleOf', 'default', '$ref', 'oneOf']
	'minItems' is not one of ['description', 'deprecated', 'const', 'enum', 'minimum', 'maximum', 'multipleOf', 'default', '$ref', 'oneOf']
	1 is less than the minimum of 2
		hint: Arrays must be described with a combination of minItems/maxItems/items
	hint: cell array properties must define how many entries and what the entries are when there is more than one entry.
	from schema $id: http://devicetree.org/meta-schemas/cell.yaml
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/net/wiznet,w5x00.yaml: properties:interrupts: 'anyOf' conditional failed, one must be fixed:
	'minItems' is not one of ['maxItems', 'description', 'deprecated']
		hint: Only "maxItems" is required for a single entry if there are no constraints defined for the values.
	'maxItems' is not one of ['description', 'deprecated', 'const', 'enum', 'minimum', 'maximum', 'multipleOf', 'default', '$ref', 'oneOf']
	'minItems' is not one of ['description', 'deprecated', 'const', 'enum', 'minimum', 'maximum', 'multipleOf', 'default', '$ref', 'oneOf']
	1 is less than the minimum of 2
		hint: Arrays must be described with a combination of minItems/maxItems/items
	hint: cell array properties must define how many entries and what the entries are when there is more than one entry.
	from schema $id: http://devicetree.org/meta-schemas/cell.yaml
Error: Documentation/devicetree/bindings/net/wiznet,w5x00.example.dts:33.23-24 syntax error
FATAL ERROR: Unable to parse input tree
make[2]: *** [scripts/Makefile.dtbs:140: Documentation/devicetree/bindings/net/wiznet,w5x00.example.dtb] Error 1
make[2]: *** Waiting for unfinished jobs....
make[1]: *** [/builds/robherring/dt-review-ci/linux/Makefile:1703: dt_binding_check] Error 2
make: *** [Makefile:248: __sub-make] Error 2

doc reference errors (make refcheckdocs):

See https://patchwork.kernel.org/project/devicetree/patch/20260804-wiznet-link-gpio-v2-2-3b1d0c870f35@marmottus.net

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.

Re: [PATCH v2 1/2] w5100: restore GPIO-based link detection

[Jakub Kicinski]

On Tue, 04 Aug 2026 19:40:56 +0200 Arthur Crépin Leblond wrote:
> Commit dacf281771a9 ("w5100: remove unused gpio link detection")

Sounds like a fix, so the two patches should probably travel separately,
the fix with a Fixes tag and more explanation (what you have in the
cover letter and more) in the message.

And the conversion should travel via net-next.

Re: [PATCH v2 1/2] w5100: restore GPIO-based link detection

[Arnd Bergmann]

On Tue, Aug 4, 2026, at 22:58, Jakub Kicinski wrote:
> On Tue, 04 Aug 2026 19:40:56 +0200 Arthur Crépin Leblond wrote:
>> Commit dacf281771a9 ("w5100: remove unused gpio link detection")
>
> Sounds like a fix, so the two patches should probably travel separately,
> the fix with a Fixes tag and more explanation (what you have in the
> cover letter and more) in the message.
>
> And the conversion should travel via net-next.

It's not really a fix for my patch though: the original code never
worked on mainline kernels because the w5100_spi_probe() function
always passed -EINVAL as the gpio number since it was first added in
630cf09751fe ("net: w5100: support SPI interface mode"). Arthur
correctly adds support for the link gpio line using DT probing.

I would suggest rewording the patch description to clarify this
by describing what the added code does first before mentioning
the removal of the old version.

      Arnd

Re: [PATCH v2 2/2] dt-bindings: net: convert wiznet,w5x00 to YAML

[Krzysztof Kozlowski]

On 04/08/2026 19:40, Arthur Crépin Leblond wrote:
> Convert the Wiznet w5x00 SPI Ethernet controller binding from
> text to DT schema format.

Limited review, to spare you one review cycle, as it was not tested.

Subject: s/YAML/DT schema/

See also:
https://elixir.bootlin.com/linux/v7.1-rc7/source/Documentation/devicetree/bindings/submitting-patches.rst#L23

> 
> Signed-off-by: Arthur Crépin Leblond <arthur@marmottus.net>
> ---
>  .../devicetree/bindings/net/wiznet,w5x00.txt       |  50 ----------
>  .../devicetree/bindings/net/wiznet,w5x00.yaml      | 103 +++++++++++++++++++++
>  2 files changed, 103 insertions(+), 50 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/net/wiznet,w5x00.txt b/Documentation/devicetree/bindings/net/wiznet,w5x00.txt
> deleted file mode 100644
> index e9665798c4be..000000000000
> --- a/Documentation/devicetree/bindings/net/wiznet,w5x00.txt
> +++ /dev/null
> @@ -1,50 +0,0 @@
> -* Wiznet w5x00
> -
> -This is a standalone 10/100 MBit Ethernet controller with SPI interface.
> -
> -For each device connected to a SPI bus, define a child node within
> -the SPI master node.
> -
> -Required properties:
> -- compatible: Should be one of the following strings:
> -	      "wiznet,w5100"
> -	      "wiznet,w5200"
> -	      "wiznet,w5500"
> -- reg: Specify the SPI chip select the chip is wired to.
> -- interrupts: Specify the interrupt index within the interrupt controller (referred
> -              to above in interrupt-parent) and interrupt type. w5x00 natively
> -              generates falling edge interrupts, however, additional board logic
> -              might invert the signal.
> -- pinctrl-names: List of assigned state names, see pinctrl binding documentation.
> -- pinctrl-0: List of phandles to configure the GPIO pin used as interrupt line,
> -             see also generic and your platform specific pinctrl binding
> -             documentation.
> -
> -Optional properties:
> -- spi-max-frequency: Maximum frequency of the SPI bus when accessing the w5500.
> -  According to the w5500 datasheet, the chip allows a maximum of 80 MHz, however,
> -  board designs may need to limit this value.
> -- local-mac-address: See ethernet.txt in the same directory.
> -
> -
> -Example (for Raspberry Pi with pin control stuff for GPIO irq):
> -
> -&spi {
> -	ethernet@0: w5500@0 {
> -		compatible = "wiznet,w5500";
> -		reg = <0>;
> -		pinctrl-names = "default";
> -		pinctrl-0 = <&eth1_pins>;
> -		interrupt-parent = <&gpio>;
> -		interrupts = <25 IRQ_TYPE_EDGE_FALLING>;
> -		spi-max-frequency = <30000000>;
> -	};
> -};
> -
> -&gpio {
> -	eth1_pins: eth1_pins {
> -		brcm,pins = <25>;
> -		brcm,function = <0>; /* in */
> -		brcm,pull = <0>; /* none */
> -	};
> -};
> diff --git a/Documentation/devicetree/bindings/net/wiznet,w5x00.yaml b/Documentation/devicetree/bindings/net/wiznet,w5x00.yaml
> new file mode 100644
> index 000000000000..8f45a5d773fe
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/wiznet,w5x00.yaml

Filename: wiznet,w5100.yaml

> @@ -0,0 +1,103 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/net/wiznet,w5x00.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Wiznet w5x00 SPI Ethernet Controller
> +
> +description: |
> +  This is a standalone 10/100 MBit Ethernet controller with SPI interface.
> +
> +  For each device connected to a SPI bus, define a child node within the SPI master node.

This looks unwrapped (see Linux coding style).

> +
> +allOf:
> +  - $ref: /schemas/net/ethernet-controller.yaml#
> +  - $ref: /schemas/spi/spi-peripheral-props.yaml#
> +
> +properties:
> +  compatible:
> +    enum:
> +      - wiznet,w5100
> +      - wiznet,w5200
> +      - wiznet,w5500
> +
> +  reg:
> +    description: Specify the SPI chip select the chip is wired to.
> +    maxItems: 1
> +    minItems: 1

Drop, please do not invent your own syntax. Look at recently reviewed
code or example-schema.

> +
> +  interrupts:
> +    description:
> +      Specify the interrupt index within the interrupt controller (referred to
> +      above in interrupt-parent) and interrupt type. w5x00 natively generates
> +      falling edge interrupts, however, additional board logic might invert the
> +      signal.
> +    maxItems: 1
> +    minItems: 1
> +
> +  pinctrl-names:
> +    description:
> +      List of assigned state names, see pinctrl binding documentation.
> +    enum:
> +      - default
> +    minItems: 1

Do not invent own code. Drop

> +
> +  pinctrl-0:
> +    description:
> +      List of phandles to configure the GPIO pin used as interrupt line, see
> +      also generic and your platform specific pinctrl binding documentation.
> +    minItems: 1
> +
> +  local-mac-address: true
> +
> +  spi-max-frequency:
> +    description:
> +      Maximum frequency of the SPI bus when accessing the w5500. According to
> +      the w5500 datasheet, the chip allows a maximum of 80 MHz, however, board
> +      designs may need to limit this value.
> +    maximum: 80000000
> +
> +  link-gpios:
> +    description: A GPIO line used for the link detection interrupt.
> +    maxItems: 1

This wasn't in the original binding and lacks explanation in commit msg.
Any change done to the binding must be documented with a reason WHY. If
there is no reason WHY, then maybe you wanted separate commit (although
each commit should explain WHY).

> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - pinctrl-names
> +  - pinctrl-0
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    /* Example (for Raspberry Pi with pin control stuff for GPIO irq) */
> +
> +    #include <dt-bindings/gpio/gpio.h>
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +
> +    spi {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        ethernet@0: w5500@0 {
> +          compatible = "wiznet,w5500";
> +            reg = <0>;
> +            pinctrl-names = "default";

Messed indentation.

> +            pinctrl-0 = <&eth1_pins>;
> +            interrupt-parent = <&gpio>;
> +            interrupts = <25 IRQ_TYPE_EDGE_FALLING>;
> +            spi-max-frequency = <30000000>;
> +            link-gpios = <&gpio 4 GPIO_ACTIVE_HIGH>;
> +            local-mac-address = [ a0 b0 c0 d0 e0 f0 ];
> +        };
> +    };
> +
> +    &gpio {
> +      eth1_pins: eth1_pins {
> +        brcm,pins = <25 4>;
> +        brcm,function = <0 0>; /* in */
> +        brcm,pull = <0 0>; /* none */
> +    };

Irrelevant node, drop

Best regards,
Krzysztof

Re: [PATCH v2 2/2] dt-bindings: net: convert wiznet,w5x00 to YAML

[Arthur Crépin Leblond]

On Wed, Aug 05, 2026 at 01:08:35PM +0200, Krzysztof Kozlowski wrote:
>On 04/08/2026 19:40, Arthur Crépin Leblond wrote:
>> Convert the Wiznet w5x00 SPI Ethernet controller binding from
>> text to DT schema format.
>
>Limited review, to spare you one review cycle, as it was not tested.
>
>Subject: s/YAML/DT schema/
>
>See also:
>https://elixir.bootlin.com/linux/v7.1-rc7/source/Documentation/devicetree/bindings/submitting-patches.rst#L23
>

Hi Krzysztof,

Thank you for the review, I'll address all the changes in a new patch.
Quick question, since there was no maintainer on that text file, who
should I assign it to?

Thanks

Arthur

Re: [PATCH v2 1/2] w5100: restore GPIO-based link detection

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:
- [High] The devm-managed link IRQ outlives the manually freed network device, leading to a Use-After-Free in the interrupt handler during driver removal.
- [Medium] The threaded interrupt handler uses the non-sleepable `gpiod_get_value()` instead of `gpiod_get_value_cansleep()`, which will trigger a kernel WARNING if the GPIO chip can sleep.
- [Medium] Race condition between the initial link state check in `w5100_open` and the edge-triggered link IRQ, leading to a desynchronized carrier state.
--

--- Patch [1]: [PATCH v2 1/2] w5100: restore GPIO-based link detection ---
commit 48dd7a12d64614af31aae8617e2d9b17300b7e8a
Author: Arthur Crépin Leblond <arthur@marmottus.net>

w5100: restore GPIO-based link detection

Commit dacf281771a9 ("w5100: remove unused gpio link detection")
dropped the link_gpio/link_irq handling on the grounds that no
devicetree user passed a "link" GPIO at the time.

This isn't a plain revert of that removal. The link GPIO is now
bound from the device tree link-gpios property using the resource
managed GPIO descriptors.

The link IRQ is also requested with devm_request_threaded_irq()
instead of request_any_context_irq(), so it is released automatically
on driver removal or probe failure.

> diff --git a/drivers/net/ethernet/wiznet/w5100.c b/drivers/net/ethernet/wiznet/w5100.c
> index 53d8dc642fbd6..1410a9fcfa921 100644
> --- a/drivers/net/ethernet/wiznet/w5100.c
> +++ b/drivers/net/ethernet/wiznet/w5100.c
[ ... ]
> @@ -616,6 +628,24 @@ static irqreturn_t w5100_interrupt(int irq, void *ndev_instance)
>  	return IRQ_HANDLED;
>  }
>  
> +static irqreturn_t w5100_detect_link(int irq, void *ndev_instance)
> +{
> +	struct net_device *ndev = ndev_instance;
> +	struct w5100_priv *priv = netdev_priv(ndev);
> +
> +	if (netif_running(ndev)) {
> +		if (gpiod_get_value(priv->link_gpio) != 0) {

[Severity: Medium]
Will this trigger a warning if the GPIO controller can sleep?

Since w5100_detect_link() is registered as a threaded IRQ handler, it is
allowed to sleep. If the underlying GPIO controller is sleepable (like an I2C
or SPI expander), using the non-sleepable gpiod_get_value() will trigger a
WARN_ON. Should this use gpiod_get_value_cansleep() instead?

> +			netif_info(priv, link, ndev, "link is up\n");
> +			netif_carrier_on(ndev);
> +		} else {
> +			netif_info(priv, link, ndev, "link is down\n");
> +			netif_carrier_off(ndev);
> +		}
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +
[ ... ]
> @@ -659,6 +689,14 @@ static int w5100_open(struct net_device *ndev)
>  	w5100_hw_start(priv);
>  	napi_enable(&priv->napi);
>  	netif_start_queue(ndev);
> +
> +	if (priv->link_gpio) {
> +		if (gpiod_get_value_cansleep(priv->link_gpio) != 0)
> +			netif_carrier_on(ndev);
> +		else
> +			netif_carrier_off(ndev);
> +	}
> +

[Severity: Medium]
Can this race with the w5100_detect_link() IRQ handler?

If a physical link change triggers an interrupt right after the GPIO value
is read but before netif_carrier_on/off is called, the IRQ handler will run
and correctly update the carrier state.

Once the IRQ handler completes, w5100_open() will continue and overwrite the
carrier state with the stale value it read earlier. Because the link IRQ is
edge-triggered, no further interrupts will correct this desynchronization.

>  	return 0;
>  }
[ ... ]
> @@ -803,8 +849,29 @@ int w5100_probe(struct device *dev, const struct w5100_ops *ops,
>  	if (err)
>  		goto err_hw;
>  
> +	if (priv->link_gpio) {
> +		int link_irq = gpiod_to_irq(priv->link_gpio);
> +
> +		if (link_irq < 0) {
> +			err = dev_err_probe(dev, link_irq,
> +					    "No corresponding irq for link gpio\n");
> +			goto err_gpio;
> +		}
> +
> +		err = devm_request_threaded_irq(dev, link_irq, NULL,
> +						w5100_detect_link,
> +						IRQF_TRIGGER_RISING |
> +						IRQF_TRIGGER_FALLING |
> +						IRQF_ONESHOT,
> +						"w5100-link", priv->ndev);

[Severity: High]
Does this introduce a Use-After-Free during driver removal?

Since devm_request_threaded_irq() is used, the IRQ is automatically released
by devres after the driver's remove function returns.

However, w5100_remove() manually frees the network device:

drivers/net/ethernet/wiznet/w5100.c:w5100_remove() {
    ...
	unregister_netdev(ndev);
	free_netdev(ndev);
}

If a link interrupt fires after free_netdev() but before devres cleans up
the IRQ, w5100_detect_link() will be called and dereference the freed ndev
pointer.

> +		if (err < 0)
> +			goto err_gpio;
> +	}
> +
>  	return 0;

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260804-wiznet-link-gpio-v2-0-3b1d0c870f35@marmottus.net?part=1

Re: [PATCH v2 2/2] dt-bindings: net: convert wiznet,w5x00 to YAML

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Low] The device tree example contains multiple syntax errors and unresolved references that will cause `make dt_binding_check` to fail fatally.
- [Low] The `pinctrl-names` property incorrectly uses `enum` alongside `minItems: 1` for a string array constraint.
--

--- Patch [2]: [PATCH v2 2/2] dt-bindings: net: convert wiznet,w5x00 to YAML ---
commit 03b1fc0266172468d4c1e28d10eec5fa26175fe7
Author: Arthur Crépin Leblond <arthur@marmottus.net>

dt-bindings: net: convert wiznet,w5x00 to YAML
    
Convert the Wiznet w5x00 SPI Ethernet controller binding from
text to DT schema format.

> diff --git a/Documentation/devicetree/bindings/net/wiznet,w5x00.yaml b/Documentation/devicetree/bindings/net/wiznet,w5x00.yaml
> new file mode 100644
> index 0000000000000..8f45a5d773fe3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/wiznet,w5x00.yaml
> @@ -0,0 +1,103 @@
[ ... ]
> +  pinctrl-names:
> +    description:
> +      List of assigned state names, see pinctrl binding documentation.
> +    enum:
> +      - default
> +    minItems: 1

[Severity: Low]
Does this incorrectly restrict pinctrl-names to a scalar string instead of a
string-array?

Since pinctrl-names is inherently defined as a string-array, using
enum: [ default ] restricts the property to a scalar string, which will cause
schema validation to fail for valid device trees. The standard approach
requires:

  items:
    - const: default

[ ... ]
> +examples:
> +  - |
> +    /* Example (for Raspberry Pi with pin control stuff for GPIO irq) */
> +
> +    #include <dt-bindings/gpio/gpio.h>
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +
> +    spi {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        ethernet@0: w5500@0 {

[Severity: Low]
Is the label ethernet@0 valid here?

DTS labels cannot contain the '@' character. This will cause a strict
compilation failure when this YAML example is parsed by dtc during
make dt_binding_check.

> +          compatible = "wiznet,w5500";
> +            reg = <0>;
> +            pinctrl-names = "default";
> +            pinctrl-0 = <&eth1_pins>;
> +            interrupt-parent = <&gpio>;

[Severity: Low]
Could this unresolved &gpio phandle reference cause a compiler error during
dt_binding_check?

Since &gpio is not defined in the scope of this standalone example, dtc will
fail to resolve it.

> +            interrupts = <25 IRQ_TYPE_EDGE_FALLING>;
> +            spi-max-frequency = <30000000>;
> +            link-gpios = <&gpio 4 GPIO_ACTIVE_HIGH>;
> +            local-mac-address = [ a0 b0 c0 d0 e0 f0 ];
> +        };
> +    };
> +
> +    &gpio {
> +      eth1_pins: eth1_pins {
> +        brcm,pins = <25 4>;
> +        brcm,function = <0 0>; /* in */
> +        brcm,pull = <0 0>; /* none */
> +    };

[Severity: Low]
Are we missing a final closing brace for the &gpio node here?

This syntax error seems to have been introduced during the conversion from
the text binding, and it will prevent make dt_binding_check from compiling
the example.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260804-wiznet-link-gpio-v2-0-3b1d0c870f35@marmottus.net?part=2