arm64: dts: apple: t8112-j473: Use dcpext for HDMI out

dcp on t8112 and t602x does not wake up after sleep + reset but dcpext*
does. Use dcpext0 for sharing the code with M1* devices.
My interpretation of the tea leaves from Apple's marketing department
suggests that dcpext is more capable (6k 60Hz vs 5k 60Hz) so use dcpext
as long as only one is used.

Signed-off-by: Janne Grunau <[email protected]>

Author: jannau

arch/arm64/boot/dts/apple/t8112-j473.dts

@@ -18,20 +18,38 @@
 
 	aliases {
 		bluetooth0 = &bluetooth0;
+		/delete-property/ dcp;
+		dcpext = &dcpext;
 		ethernet0 = &ethernet0;
 		wifi0 = &wifi0;
 	};
 };
 
 &framebuffer0 {
-	power-domains = <&ps_disp0_cpu0>, <&ps_dptx_ext_phy>;
+	power-domains = <&ps_dispext_cpu0>, <&ps_dptx_ext_phy>;
 };
 
 &dptxphy {
 	status = "okay";
 };
 
 &dcp {
+	status = "disabled";
+};
+
+&display {
+	iommus = <&dispext0_dart 0>;
+};
+&dispext0_dart {
+	status = "okay";
+};
+&dcpext_dart {
+	status = "okay";
+};
+&dcpext_mbox {
+	status = "okay";
+};
+&dcpext {
 	status = "okay";
 	apple,connector-type = "HDMI-A";