[PATCH v2] dt-bindings: usb: maxim,max3421: convert to DT schema

[Rodrigo Gobbi <rodrigo.gobbi.7@gmail.com>]

Convert legacy maxim,max3421.txt to proper format.

Signed-off-by: Rodrigo Gobbi <rodrigo.gobbi.7@gmail.com>
---
Hi, all

At this v2, I`m reverting my previous idea about documenting new properties
because this is just a conversion from txt file. At v1, a question
was raised about that:

On 10/9/25 22:34, Krzysztof Kozlowski wrote:
> maxim,vbus-en-pin, maxim,gpx-pin, reset pin and supplies. Also add a
> Why new properties? You must explain not only the difference but WHY you
> are doing this.
In this case, I`ve kept the maxim,vbus-en-pin prop because it was already
described in the legacy file and the driver expects that property according
to [1] and [2].

[1] https://github.com/torvalds/linux/blob/a1388fcb52fcad3e0b06e2cdd0ed757a82a5be30/drivers/usb/host/max3421-hcd.c#L1807
[2] https://github.com/torvalds/linux/blob/a1388fcb52fcad3e0b06e2cdd0ed757a82a5be30/drivers/usb/host/max3421-hcd.c#L1845-L1847

Tks and regards to all!

Changelog:
v2: - fix subject/commit msg;
    - remove $ref/desc from spi-max-frequency;
    - add spi-peripheral-props/unevaluatedProperties;
    - remove the "new properties";
    - remove fallback compatible with the 'e' pattern;
    - fix file name, didn`t notice at previous version;
v1: https://lore.kernel.org/all/20251009182046.185520-1-rodrigo.gobbi.7@gmail.com/
---
 .../devicetree/bindings/usb/maxim,max3421.txt | 23 -------
 .../bindings/usb/maxim,max3421.yaml           | 67 +++++++++++++++++++
 2 files changed, 67 insertions(+), 23 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/usb/maxim,max3421.txt
 create mode 100644 Documentation/devicetree/bindings/usb/maxim,max3421.yaml

diff --git a/Documentation/devicetree/bindings/usb/maxim,max3421.txt b/Documentation/devicetree/bindings/usb/maxim,max3421.txt
deleted file mode 100644
index 90495b1aeec2..000000000000
--- a/Documentation/devicetree/bindings/usb/maxim,max3421.txt
+++ /dev/null
@@ -1,23 +0,0 @@
-Maxim Integrated SPI-based USB 2.0 host controller MAX3421E
-
-Required properties:
- - compatible: Should be "maxim,max3421"
- - spi-max-frequency: maximum frequency for this device must not exceed 26 MHz.
- - reg: chip select number to which this device is connected.
- - maxim,vbus-en-pin: <GPOUTx ACTIVE_LEVEL>
-   GPOUTx is the number (1-8) of the GPOUT pin of MAX3421E to drive Vbus.
-   ACTIVE_LEVEL is 0 or 1.
- - interrupts: the interrupt line description for the interrupt controller.
-   The driver configures MAX3421E for active low level triggered interrupts,
-   configure your interrupt line accordingly.
-
-Example:
-
-	usb@0 {
-		compatible = "maxim,max3421";
-		reg = <0>;
-		maxim,vbus-en-pin = <3 1>;
-		spi-max-frequency = <26000000>;
-		interrupt-parent = <&PIC>;
-		interrupts = <42>;
-	};
diff --git a/Documentation/devicetree/bindings/usb/maxim,max3421.yaml b/Documentation/devicetree/bindings/usb/maxim,max3421.yaml
new file mode 100644
index 000000000000..4639be7ab059
--- /dev/null
+++ b/Documentation/devicetree/bindings/usb/maxim,max3421.yaml
@@ -0,0 +1,67 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/usb/maxim,max3421.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MAXIM MAX3421e USB Peripheral/Host Controller
+
+maintainers:
+  - David Mosberger <davidm@egauge.net>
+
+description: |
+  The controller provides USB2.0 compliant with Full Speed or Low Speed when in
+  the host mode. At peripheral, it operates at Full Speed. At both cases, it
+  uses a SPI interface.
+  Datasheet at:
+    https://www.analog.com/media/en/technical-documentation/data-sheets/max3421e.pdf
+
+properties:
+  compatible:
+    const: maxim,max3421
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  spi-max-frequency:
+    maximum: 26000000
+
+  maxim,vbus-en-pin:
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+    description:
+      One of eight GPOUT pins to control external VBUS power and the polarity
+      of the active level. It's an array of GPIO number and the active level of it.
+    minItems: 2
+    maxItems: 2
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - maxim,vbus-en-pin
+
+allOf:
+  - $ref: /schemas/spi/spi-peripheral-props.yaml#
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        usb@0 {
+          compatible = "maxim,max3421";
+          reg = <0>;
+          maxim,vbus-en-pin = <3 1>;
+          spi-max-frequency = <26000000>;
+          interrupt-parent = <&gpio>;
+          interrupts = <42>;
+        };
+    };
-- 
2.48.1