dts: bindings: gpio: add arducam 20-pin camera connector

Add the 20-pin camera connector used by at least Arducam, Waveshare,
Olimex, Arduino, NXP, ST, Adafruit that connects image sensor module
boards and devkits.

Signed-off-by: Josuah Demangeon <me@josuah.net>

Author: josuah

boards/nxp/frdm_mcxn947/frdm_mcxn947.dtsi

@@ -7,6 +7,7 @@
 #include "frdm_mcxn947-pinctrl.dtsi"
 #include <zephyr/dt-bindings/i2c/i2c.h>
 #include <zephyr/dt-bindings/input/input-event-codes.h>
+#include <zephyr/dt-bindings/gpio/dvp-20pin-connector.h>
 
 / {
 	aliases{
@@ -95,38 +96,22 @@ nxp_8080_touch_panel_i2c: &flexcomm2_lpi2c2 {
 	pinctrl-0 = <&pinmux_flexcomm7_lpi2c>;
 	pinctrl-names = "default";
 	clock-frequency = <I2C_BITRATE_STANDARD>;
-	ov7670: ov7670@21 {
-		compatible = "ovti,ov7670";
-		reset-gpios = <&gpio1 19 GPIO_ACTIVE_HIGH>;
-		pwdn-gpios = <&gpio1 18 GPIO_ACTIVE_HIGH>;
-		reg = <0x21>;
-
-		port {
-			ov7670_ep_out: endpoint {
-				remote-endpoint-label = "sdma_ep_in";
-			};
-		};
-	};
 };
 
 /* SmartDMA is used for video driver on this board */
 &smartdma {
+	/* Shields do not enable video-sdma parent node so enable it by default */
 	status = "okay";
 	program-mem = <0x4000000>;
+
 	video_sdma: video-sdma {
-		status = "okay";
+		status = "disabled";
 		compatible = "nxp,video-smartdma";
 		pinctrl-0 = <&pinmux_smartdma_camera>;
 		pinctrl-names = "default";
 		vsync-pin = <4>;
 		hsync-pin = <11>;
 		pclk-pin = <5>;
-
-		port {
-			sdma_ep_in: endpoint {
-				remote-endpoint-label = "ov7670_ep_out";
-			};
-		};
 	};
 };
 
@@ -300,3 +285,22 @@ zephyr_mipi_dbi_parallel: &flexio0_lcd {
 	pinctrl-0 = <&pinmux_sctimer>;
 	pinctrl-names = "default";
 };
+
+/*
+ * Connection with camera modules such as the dvp_20pin_ov7670 shield
+ */
+
+/ {
+	dvp_20pin_connector: dvp-20pin-connector {
+		compatible = "arducam,dvp-20pin-connector";
+		#gpio-cells = <2>;
+		gpio-map-mask = <0xffffffff 0xffffffc0>;
+		gpio-map-pass-thru = <0x0 GPIO_DT_FLAGS_MASK>;
+		gpio-map =	<DVP_20PIN_PEN 0 &gpio1 19 0>,
+				<DVP_20PIN_PDN 0 &gpio1 18 0>;
+	};
+};
+
+dvp_20pin_i2c: &flexcomm7_lpi2c7 {};
+
+dvp_20pin_interface: &video_sdma {};

dts/bindings/gpio/arducam,dvp-20pin-connector.yaml

@@ -0,0 +1,40 @@
+# Copyright 2025 tinyVision.ai Inc.
+# SPDX-License-Identifier: Apache-2.0
+
+description: |
+  GPIO pins exposed on ArduCam 20-pin header camera connector,
+  originally designed to connect Arducam modules to Arduino Giga R1,
+  but further used by other vendors of camera and devkits.
+
+  The connector layout is depicted below:
+
+     1   3V3          2   GND
+     3   SCL          4   SDA
+     5   VS           6   HS
+     7   PCLK         8   XCLK
+     9   D7           10  D6
+     11  D5           12  D4
+     13  D3           14  D2
+     15  D1           16  D0
+     17  PEN          18  PDN
+     19  GPIO0        20  GPIO1
+
+  In some variants, the last row containing the pins 19 and 20 is
+  not present, and the module is only providing 18 pins out of 20.
+
+  The following node labels can be used in devicetree:
+
+  - dvp_20pin_interface: the video interface that receives the video
+    feed and use with the zephyr,camera chosen node.
+
+  - dvp_20pin_i2c: the I2C device of the devkit on which the camera
+    module is instantiated.
+
+  - dvp_20pin_connector: the GPIO nexus using the arducam,dvp-20pin-connector
+    that defines the camera pins ('reset' (PEN), 'power-down' (PDN)...)
+
+  See <zephyr/dt-bindings/gpio/dvp-20pin-connector.h> for pin description.
+
+compatible: "arducam,dvp-20pin-connector"
+
+include: [gpio-nexus.yaml, base.yaml]

dts/bindings/vendor-prefixes.txt

@@ -70,6 +70,7 @@ arc	Synopsys, Inc. (formerly ARC International PLC)
 archermind	ArcherMind Technology (Nanjing) Co., Ltd.
 arctic	Arctic Sand
 arcx	arcx Inc. / Archronix Inc.
+arducam	Arducam
 arduino	Arduino
 aries	Aries Embedded GmbH
 arm	ARM Ltd.

include/zephyr/dt-bindings/gpio/dvp-20pin-connector.h

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2025 tinyVision.ai Inc.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#ifndef INCLUDE_ZEPHYR_DT_BINDINGS_GPIO_DVP_20PIN_CONNECTOR_H_
+#define INCLUDE_ZEPHYR_DT_BINDINGS_GPIO_DVP_20PIN_CONNECTOR_H_
+
+/**
+ * @name Arducam DVP 20-pin or 18-pin connector pinout
+ * @{
+ */
+#define DVP_20PIN_SCL	3	/**< I2C pin */
+#define DVP_20PIN_SDA	4	/**< I2C pin */
+#define DVP_20PIN_VS	5	/**< Vertical sync */
+#define DVP_20PIN_HS	6	/**< Horizontal sync */
+#define DVP_20PIN_PCLK	7	/**< Pixel clock used to transmit the data */
+#define DVP_20PIN_XCLK	8	/**< System clock often needed for I2C communication */
+#define DVP_20PIN_D7	9	/**< Parallel port data */
+#define DVP_20PIN_D6	10	/**< Parallel port data */
+#define DVP_20PIN_D5	11	/**< Parallel port data */
+#define DVP_20PIN_D4	12	/**< Parallel port data */
+#define DVP_20PIN_D3	13	/**< Parallel port data */
+#define DVP_20PIN_D2	14	/**< Parallel port data */
+#define DVP_20PIN_D1	15	/**< Parallel port data */
+#define DVP_20PIN_D0	16	/**< Parallel port data */
+#define DVP_20PIN_PEN	17	/**< Power Enable */
+#define DVP_20PIN_PDN	18	/**< Power Down */
+#define DVP_20PIN_GPIO0	19	/**< Extra GPIO pin present on some modules */
+#define DVP_20PIN_GPIO1	20	/**< Extra GPIO pin present on some modules */
+/** @} */
+
+#endif /* INCLUDE_ZEPHYR_DT_BINDINGS_GPIO_DVP_20PIN_CONNECTOR_H_ */