dt-bindings: fpga: Add Efinix SPI programming bindings

Add device tree bindings documentation for configuring Efinix FPGA
using serial SPI passive programming mode.

Signed-off-by: Ian Dannapel <iansdannapel@gmail.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20260416144237.373852-3-iansdannapel@gmail.com
Signed-off-by: Xu Yilun <yilun.xu@linux.intel.com>

diff --git a/Documentation/devicetree/bindings/fpga/efinix,trion-config.yaml b/Documentation/devicetree/bindings/fpga/efinix,trion-config.yaml
new file mode 100644 (file)
index 0000000..7c7444f
--- /dev/null
+++ b/Documentation/devicetree/bindings/fpga/efinix,trion-config.yaml
@@ -0,0 +1,98 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/fpga/efinix,trion-config.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Efinix SPI FPGA Manager
+
+maintainers:
+  - Ian Dannapel <iansdannapel@gmail.com>
+
+description: |
+  Efinix FPGAs (Trion, Topaz, and Titanium families) support loading bitstreams
+  through "SPI Passive Mode".
+  Additional pin hogs for bus width configuration should be set
+  elsewhere, if necessary.
+
+  References:
+  - https://www.efinixinc.com/docs/an006-configuring-trion-fpgas-v6.3.pdf
+  - https://www.efinixinc.com/docs/an033-configuring-titanium-fpgas-v2.8.pdf
+  - https://www.efinixinc.com/docs/an061-configuring-topaz-fpgas-v1.1.pdf
+
+allOf:
+  - $ref: /schemas/spi/spi-peripheral-props.yaml#
+
+properties:
+  compatible:
+    oneOf:
+      - items:
+          - enum:
+              - efinix,titanium-config
+              - efinix,topaz-config
+          - const: efinix,trion-config
+      - const: efinix,trion-config
+
+  spi-cpha: true
+
+  spi-cpol: true
+
+  spi-max-frequency:
+    maximum: 25000000
+
+  reg:
+    maxItems: 1
+
+  reset-gpios:
+    description:
+      reset and re-configuration trigger pin (low active)
+    maxItems: 1
+
+  cdone-gpios:
+    description:
+      optional configuration done status pin (high active)
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - reset-gpios
+  - spi-cpha
+  - spi-cpol
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    spi {
+      #address-cells = <1>;
+      #size-cells = <0>;
+      cs-gpios = <&gpio5 13 GPIO_ACTIVE_LOW>;
+      fpga-mgr@0 {
+        compatible = "efinix,trion-config";
+        reg = <0>;
+        spi-max-frequency = <25000000>;
+        spi-cpha;
+        spi-cpol;
+        reset-gpios = <&gpio4 17 GPIO_ACTIVE_LOW>;
+        cdone-gpios = <&gpio0 9 GPIO_ACTIVE_HIGH>;
+      };
+    };
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    spi {
+      #address-cells = <1>;
+      #size-cells = <0>;
+      cs-gpios = <&gpio5 13 GPIO_ACTIVE_LOW>;
+      fpga-mgr@0 {
+        compatible = "efinix,titanium-config", "efinix,trion-config";
+        reg = <0>;
+        spi-max-frequency = <25000000>;
+        spi-cpha;
+        spi-cpol;
+        reset-gpios = <&gpio4 17 GPIO_ACTIVE_LOW>;
+        cdone-gpios = <&gpio0 9 GPIO_ACTIVE_HIGH>;
+      };
+    };
+...