[PATCH 3/3] arm64: dts: qcom: qcm6490-fairphone-fp5: Add DisplayPort sound support

[Luca Weiss <luca.weiss@fairphone.com>]

Add the required nodes for sound playback via a connected external
display (DisplayPort over USB-C).

In user space just the following route needs to be set (e.g. using
ALSA UCM):

  amixer -c0 cset name='DISPLAY_PORT_RX Audio Mixer MultiMedia1' 1

Afterwards one can play audio on the MultiMedia1 sound device, e.g.:

  aplay -D plughw:0,0 test.wav

Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
---
(from cover letter)
Unfortunately DisplayPort enablement itself for Fairphone 5 is not
upstream yet. This is blocked by DSI display bringup upstream which is
blocked by DSC 1:1:1 not being supported upstream yet and just working
with a hacky patch. Nevertheless, DisplayPort audio was validated
working with no additional sound-related changes so once DisplayPort
gets enabled, sound should also just work upstream.
---
 arch/arm64/boot/dts/qcom/qcm6490-fairphone-fp5.dts | 37 ++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/qcm6490-fairphone-fp5.dts b/arch/arm64/boot/dts/qcom/qcm6490-fairphone-fp5.dts
index 8ab30c01712e..45d4512546fe 100644
--- a/arch/arm64/boot/dts/qcom/qcm6490-fairphone-fp5.dts
+++ b/arch/arm64/boot/dts/qcom/qcm6490-fairphone-fp5.dts
@@ -14,6 +14,8 @@
 #include <dt-bindings/leds/common.h>
 #include <dt-bindings/pinctrl/qcom,pmic-gpio.h>
 #include <dt-bindings/regulator/qcom,rpmh-regulator.h>
+#include <dt-bindings/sound/qcom,q6afe.h>
+#include <dt-bindings/sound/qcom,q6asm.h>
 #include "sc7280.dtsi"
 #include "pm7250b.dtsi"
 #include "pm7325.dtsi"
@@ -841,6 +843,12 @@ &pon_resin {
 	status = "okay";
 };
 
+&q6afedai {
+	dai@104 {
+		reg = <DISPLAY_PORT_RX>;
+	};
+};
+
 &qup_spi13_cs {
 	drive-strength = <6>;
 	bias-disable;
@@ -914,6 +922,35 @@ &sdhc_2 {
 	status = "okay";
 };
 
+&sound {
+	compatible = "qcom,qcm6490-sndcard";
+	model = "Fairphone 5";
+
+	mm1-dai-link {
+		link-name = "MultiMedia1";
+
+		cpu {
+			sound-dai = <&q6asmdai MSM_FRONTEND_DAI_MULTIMEDIA1>;
+		};
+	};
+
+	displayport-rx-dai-link {
+		link-name = "DisplayPort Playback";
+
+		cpu {
+			sound-dai = <&q6afedai DISPLAY_PORT_RX>;
+		};
+
+		platform {
+			sound-dai = <&q6routing>;
+		};
+
+		codec {
+			sound-dai = <&mdss_dp>;
+		};
+	};
+};
+
 &spi13 {
 	status = "okay";
 

-- 
2.46.0