arm64: dts: rockchip: describe the OV8858 user camera on PinePhone Pro

Add the description of the front/user camera (OV8858) on the PinePhone Pro
to the device dts file.
It receives commands over SCCB, an I2C-compatible protocol, at
I2C address 0x36 and transmits data over CSI-MIPI.
I confirmed this address experimentally.

The pin control mapping was again extracted from the PinePhone Pro
schematic v1.0 as well as the RK3399 datasheet revision 1.8.

Table 2-3 in section 2.8 of the RK3399 datasheet contains the mapping
of IO functions for the SoC pins. Page 52 shows GPIO1_A4, page 54 shows
GPIO2_B4.

For the reset (RESET) signal:
page 11 quadrant D2             | p.18 q.B3-4 | p.18 q.C2
RK3399_E.R28 -> GPIO1_A4 -> Camera2_RST -> MIPI_RST1 -> OV8858.12

For the powerdown (PWDN) signal:
page 9 quadrants D4-5          | p.18 q.B2
RK3399_L.F31 -> GPIO2_B4 -> DVP_PDN0_H -> OV8858.14

Helped-by: Dragan Simic <dsimic@manjaro.org>
Co-developed-by: Ondrej Jirman <megi@xff.cz>
Signed-off-by: Ondrej Jirman <megi@xff.cz>
Signed-off-by: Olivier Benjamin <olivier.benjamin@bootlin.com>
Link: https://lore.kernel.org/r/20250620-camera-v4-4-0201a8ed5fae@bootlin.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

Author: oli-ben

arch/arm64/boot/dts/rockchip/rk3399-pinephone-pro.dts

@@ -480,6 +480,27 @@
 		/* Same I2c bus as both cameras, depends on vcca1v8_codec for power. */
 		vcc-supply = <&vcc1v8_dvp>;
 	};
+
+	ucam: camera@36 {
+		compatible = "ovti,ov8858";
+		reg = <0x36>;
+		clocks = <&cru SCLK_CIF_OUT>; /* MIPI_MCLK1, derived from CIF_CLK0 */
+		clock-names = "xvclk";
+		dovdd-supply = <&vcc1v8_dvp>;
+		orientation = <0>; /* V4L2_CAMERA_ORIENTATION_FRONT */
+		pinctrl-names = "default";
+		pinctrl-0 = <&camera2_rst_l &dvp_pdn0_h>;
+		powerdown-gpios = <&gpio2 RK_PB4 GPIO_ACTIVE_LOW>;
+		reset-gpios = <&gpio1 RK_PA4 GPIO_ACTIVE_LOW>;
+		rotation = <90>;
+
+		port {
+			ucam_out: endpoint {
+				data-lanes = <1 2 3 4>;
+				remote-endpoint = <&mipi_in_ucam>;
+			};
+		};
+	};
 };
 
 &i2c3 {
@@ -524,6 +545,24 @@
 	status = "okay";
 };
 
+&isp0 {
+	status = "okay";
+
+	ports {
+		port@0 {
+			mipi_in_ucam: endpoint@0 {
+				reg = <0>;
+				data-lanes = <1 2 3 4>;
+				remote-endpoint = <&ucam_out>;
+			};
+		};
+	};
+};
+
+&isp0_mmu {
+	status = "okay";
+};
+
 &isp1 {
 	status = "okay";
 
@@ -596,10 +635,16 @@
 		};
 	};
 
-	camera {
+	cameras {
 		camera_rst_l: camera-rst-l {
 			rockchip,pins = <1 RK_PA0 RK_FUNC_GPIO &pcfg_pull_none>;
 		};
+		camera2_rst_l: camera2-rst-l {
+			rockchip,pins = <1 RK_PA4 RK_FUNC_GPIO &pcfg_pull_none>;
+		};
+		dvp_pdn0_h: dvp-pdn0-h {
+			rockchip,pins = <2 RK_PB4 RK_FUNC_GPIO &pcfg_pull_none>;
+		};
 	};
 
 	leds {