[PATCH 2/2] arm64: dts: rockchip: add USB-C DP altmode support to LubanCat 4

[Pufan Jin <cyan2254650260@gmail.com>]

The Type-C port on the EmbedFire LubanCat 4 supports DisplayPort
alternate mode through the RK3588 usbdp combo PHY (usbdp_phy0).
The sideband use (SBU1/SBU2) AUX signals are routed through two DC
switches controlled by GPIO4_B3 and GPIO4_B4.

Add the DisplayPort alternate mode entry (SVID 0xff01) to the USB-C
connector and connect connector port@2 (SBU) to usbdp_phy0 port@3.
Configure usbdp_phy0 with mode-switch and sbu{1,2}-dc-gpios.  Enable
dp0 and connect dp0_out to usbdp_phy0 port@2, with dp0_in fed from
VOP2 VP1.

Tested driver stack registration on LubanCat 4 hardware:
- dw_dp bounds successfully to display-subsystem;
- DRM DP connector card2-DP-1 is registered and reports disconnected;
- typec_displayport registers the DisplayPort altmode driver;
- usbdp_phy0 registers the phy-switch and phy-mux.
Physical DisplayPort link training and monitor video output are pending
verification with a physical USB-C to DP sink/cable.

Signed-off-by: Pufan Jin <cyan2254650260@gmail.com>
---
 .../boot/dts/rockchip/rk3588s-lubancat-4.dts  | 57 +++++++++++++++++++
 1 file changed, 57 insertions(+)

diff --git a/arch/arm64/boot/dts/rockchip/rk3588s-lubancat-4.dts b/arch/arm64/boot/dts/rockchip/rk3588s-lubancat-4.dts
index a94aaddb2..6c5a942df 100644
--- a/arch/arm64/boot/dts/rockchip/rk3588s-lubancat-4.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3588s-lubancat-4.dts
@@ -323,6 +323,13 @@ usb_con: connector {
 			source-pdos =
 				<PDO_FIXED(5000, 2000, PDO_FIXED_USB_COMM)>;
 
+			altmodes {
+				displayport {
+					svid = /bits/ 16 <0xff01>;
+					vdo = <0xffffffff>;
+				};
+			};
+
 			ports {
 				#address-cells = <1>;
 				#size-cells = <0>;
@@ -342,6 +349,14 @@ usbc0_ss: endpoint {
 						remote-endpoint = <&usbdp_phy0_ss_out>;
 					};
 				};
+
+				port@2 {
+					reg = <2>;
+
+					usbc0_sbu: endpoint {
+						remote-endpoint = <&usbdp_phy0_dp_out>;
+					};
+				};
 			};
 		};
 	};
@@ -857,6 +872,9 @@ &usb_host2_xhci {
 
 &usbdp_phy0 {
 	orientation-switch;
+	mode-switch;
+	sbu1-dc-gpios = <&gpio4 RK_PB3 GPIO_ACTIVE_HIGH>;
+	sbu2-dc-gpios = <&gpio4 RK_PB4 GPIO_ACTIVE_HIGH>;
 	status = "okay";
 
 	ports {
@@ -878,6 +896,22 @@ usbdp_phy0_ss_in: endpoint {
 				remote-endpoint = <&usb_host0_xhci_ss>;
 			};
 		};
+
+		port@2 {
+			reg = <2>;
+
+			usbdp_phy0_dp_in: endpoint {
+				remote-endpoint = <&dp0_out_con>;
+			};
+		};
+
+		port@3 {
+			reg = <3>;
+
+			usbdp_phy0_dp_out: endpoint {
+				remote-endpoint = <&usbc0_sbu>;
+			};
+		};
 	};
 };
 
@@ -895,3 +929,26 @@ vp0_out_hdmi0: endpoint@ROCKCHIP_VOP2_EP_HDMI0 {
 		remote-endpoint = <&hdmi0_in_vp0>;
 	};
 };
+
+&dp0 {
+	status = "okay";
+};
+
+&dp0_in {
+	dp0_in_vp1: endpoint {
+		remote-endpoint = <&vp1_out_dp0>;
+	};
+};
+
+&dp0_out {
+	dp0_out_con: endpoint {
+		remote-endpoint = <&usbdp_phy0_dp_in>;
+	};
+};
+
+&vp1 {
+	vp1_out_dp0: endpoint@a {
+		reg = <ROCKCHIP_VOP2_EP_DP0>;
+		remote-endpoint = <&dp0_in_vp1>;
+	};
+};
-- 
2.56.0