From: Tzuyi Chang <tychang@realtek.com>

Add the device tree bindings for the Realtek DHC (Digital Home Center)
RTD1625 GPIO controllers.

The RTD1625 GPIO controller features a per-pin register architecture
that differs significantly from previous generations. It utilizes
separate register blocks for GPIO configuration and interrupt control.

Signed-off-by: Tzuyi Chang <tychang@realtek.com>
Signed-off-by: Yu-Chun Lin <eleanor.lin@realtek.com>
---
 .../bindings/gpio/realtek,rtd1625-gpio.yaml   | 74 +++++++++++++++++++
 1 file changed, 74 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/gpio/realtek,rtd1625-gpio.yaml

diff --git a/Documentation/devicetree/bindings/gpio/realtek,rtd1625-gpio.yaml b/Documentation/devicetree/bindings/gpio/realtek,rtd1625-gpio.yaml
new file mode 100644
index 000000000000..e81d13dfefc2
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/realtek,rtd1625-gpio.yaml
@@ -0,0 +1,74 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+# Copyright 2023 Realtek Semiconductor Corporation
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/gpio/realtek,rtd1625-gpio.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Realtek DHC RTD1625 GPIO controller
+
+maintainers:
+  - Tzuyi Chang <tychang@realtek.com>
+
+description: |
+  GPIO controller for the Realtek RTD1625 SoC, featuring a per-pin register
+  architecture that differs significantly from earlier RTD series controllers.
+  Each GPIO has dedicated registers for configuration (direction, input/output
+  values, debounce), and interrupt control supporting edge and level detection
+  modes.
+
+properties:
+  compatible:
+    enum:
+      - realtek,rtd1625-iso-gpio
+      - realtek,rtd1625-isom-gpio
+
+  reg:
+    items:
+      - description: GPIO controller registers
+      - description: GPIO interrupt registers
+
+  interrupts:
+    items:
+      - description: Interrupt number of the assert GPIO interrupt, which is
+                     triggered when there is a rising edge.
+      - description: Interrupt number of the deassert GPIO interrupt, which is
+                     triggered when there is a falling edge.
+      - description: Interrupt number of the level-sensitive GPIO interrupt,
+                     triggered by a configured logic level.
+
+  interrupt-controller: true
+
+  "#interrupt-cells":
+    const: 2
+
+  gpio-ranges: true
+
+  gpio-controller: true
+
+  "#gpio-cells":
+    const: 2
+
+required:
+  - compatible
+  - reg
+  - gpio-ranges
+  - gpio-controller
+  - "#gpio-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    gpio@89120 {
+      compatible = "realtek,rtd1625-isom-gpio";
+      reg = <0x89120 0x10>,
+            <0x89100 0x20>;
+      interrupt-parent = <&iso_m_irq_mux>;
+      interrupts = <0>, <1>, <2>;
+      interrupt-controller;
+      #interrupt-cells = <2>;
+      gpio-ranges = <&isom_pinctrl 0 0 4>;
+      gpio-controller;
+      #gpio-cells = <2>;
+    };
-- 
2.34.1

On Tue, Mar 31, 2026 at 07:38:33PM +0800, Yu-Chun Lin wrote:
> +  reg:
> +    items:
> +      - description: GPIO controller registers
> +      - description: GPIO interrupt registers
> +
> +  interrupts:
> +    items:
> +      - description: Interrupt number of the assert GPIO interrupt, which is
> +                     triggered when there is a rising edge.
> +      - description: Interrupt number of the deassert GPIO interrupt, which is
> +                     triggered when there is a falling edge.
> +      - description: Interrupt number of the level-sensitive GPIO interrupt,
> +                     triggered by a configured logic level.
> +
> +  interrupt-controller: true
> +
> +  "#interrupt-cells":
> +    const: 2
> +
> +  gpio-ranges: true
> +
> +  gpio-controller: true
> +
> +  "#gpio-cells":
> +    const: 2
> +
> +required:
> +  - compatible
> +  - reg
> +  - gpio-ranges
> +  - gpio-controller
> +  - "#gpio-cells"
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    gpio@89120 {
> +      compatible = "realtek,rtd1625-isom-gpio";
> +      reg = <0x89120 0x10>,

0x10 feels very short range.

> +            <0x89100 0x20>;

And this means it's continuous. Are you sure these are two separate
address spaces?

Best regards,
Krzysztof