[PATCH 12/12] arm64: dts: qcom: qcs6490-radxa-dragon-q6a: add LPASS CPU audio variant
From: Xilin Wu
Date: Tue Apr 07 2026 - 11:31:05 EST
Add a qcs6490-radxa-dragon-q6a-lpass-cpu.dts variant for debugging and
bring-up of the host-controlled LPASS audio path on the Radxa Dragon
Q6A.
This variant enables the LPASS blocks and codec macros needed by the
lpass-cpu driver, wires WCD9380 playback/capture and DisplayPort audio
to the LPASS CDC DMA and DP interfaces, and disables remoteproc_adsp so
that the audio hardware is owned directly by Linux.
This DTB is an optional configuration for systems booted with the kernel
running at EL2, where direct CPU access to the LPASS hardware is
available. It is useful for users who need low-latency and fully
controllable audio.
Signed-off-by: Xilin Wu <sophon@xxxxxxxxx>
---
arch/arm64/boot/dts/qcom/Makefile | 1 +
.../qcom/qcs6490-radxa-dragon-q6a-lpass-cpu.dts | 131 +++++++++++++++++++++
2 files changed, 132 insertions(+)
diff --git a/arch/arm64/boot/dts/qcom/Makefile b/arch/arm64/boot/dts/qcom/Makefile
index 4ba8e7306419..2f84ef7109b5 100644
--- a/arch/arm64/boot/dts/qcom/Makefile
+++ b/arch/arm64/boot/dts/qcom/Makefile
@@ -169,6 +169,7 @@ qcs615-ride-el2-dtbs := qcs615-ride.dtb talos-el2.dtbo
dtb-$(CONFIG_ARCH_QCOM) += qcs615-ride-el2.dtb
dtb-$(CONFIG_ARCH_QCOM) += qcs6490-radxa-dragon-q6a.dtb
+dtb-$(CONFIG_ARCH_QCOM) += qcs6490-radxa-dragon-q6a-lpass-cpu.dtb
dtb-$(CONFIG_ARCH_QCOM) += qcs6490-rb3gen2.dtb
qcs6490-rb3gen2-vision-mezzanine-dtbs := qcs6490-rb3gen2.dtb qcs6490-rb3gen2-vision-mezzanine.dtbo
diff --git a/arch/arm64/boot/dts/qcom/qcs6490-radxa-dragon-q6a-lpass-cpu.dts b/arch/arm64/boot/dts/qcom/qcs6490-radxa-dragon-q6a-lpass-cpu.dts
new file mode 100644
index 000000000000..e7ee57372d7e
--- /dev/null
+++ b/arch/arm64/boot/dts/qcom/qcs6490-radxa-dragon-q6a-lpass-cpu.dts
@@ -0,0 +1,131 @@
+// SPDX-License-Identifier: BSD-3-Clause
+/*
+ * Copyright (c) 2025-2026 Radxa Computer (Shenzhen) Co., Ltd.
+ *
+ * Direct CPU access to the LPASS hardware block on this platform is
+ * restricted by default. Booting the Linux kernel in EL2 will allow the
+ * kernel to access the LPASS hardware directly.
+ *
+ * You can achieve this by setting the Hypervisor Override BIOS setting to
+ * "Enabled" if you are using the official UEFI firmware.
+ */
+
+/dts-v1/;
+
+#include "qcs6490-radxa-dragon-q6a.dtsi"
+
+&gcc {
+ protected-clocks = <GCC_MSS_CFG_AHB_CLK>,
+ <GCC_MSS_GPLL0_MAIN_DIV_CLK_SRC>,
+ <GCC_MSS_OFFLINE_AXI_CLK>,
+ <GCC_MSS_Q6SS_BOOT_CLK_SRC>,
+ <GCC_MSS_Q6_MEMNOC_AXI_CLK>,
+ <GCC_MSS_SNOC_AXI_CLK>,
+ <GCC_QSPI_CNOC_PERIPH_AHB_CLK>,
+ <GCC_QSPI_CORE_CLK>,
+ <GCC_QSPI_CORE_CLK_SRC>,
+ <GCC_SEC_CTRL_CLK_SRC>,
+ <GCC_WPSS_AHB_BDG_MST_CLK>,
+ <GCC_WPSS_AHB_CLK>,
+ <GCC_WPSS_RSCP_CLK>;
+};
+
+&lpass_aon {
+ status = "okay";
+};
+
+&lpass_core {
+ status = "okay";
+};
+
+&lpass_cpu {
+ status = "okay";
+
+ dai-link@5 {
+ reg = <LPASS_DP_RX>;
+ };
+
+ dai-link@6 {
+ reg = <LPASS_CDC_DMA_RX0>;
+ };
+
+ dai-link@19 {
+ reg = <LPASS_CDC_DMA_TX3>;
+ };
+};
+
+&lpass_hm {
+ status = "okay";
+};
+
+&lpass_rx_macro {
+ status = "okay";
+};
+
+&lpass_tx_macro {
+ status = "okay";
+};
+
+&lpass_va_macro {
+ status = "okay";
+};
+
+&lpasscc {
+ status = "okay";
+};
+
+&remoteproc_adsp {
+ status = "disabled";
+};
+
+&sound {
+ compatible = "radxa,dragon-q6a-sndcard", "google,sc7280-herobrine";
+ model = "qcs6490-wcd938x-dp";
+
+ audio-routing = "IN1_HPHL", "HPHL_OUT",
+ "IN2_HPHR", "HPHR_OUT",
+ "AMIC2", "MIC BIAS2",
+ "TX SWR_ADC1", "ADC2_OUTPUT";
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ dai-link@0 {
+ link-name = "WCD9380 Playback";
+ reg = <0>;
+
+ cpu {
+ sound-dai = <&lpass_cpu LPASS_CDC_DMA_RX0>;
+ };
+
+ codec {
+ sound-dai = <&wcd938x 0>, <&swr0 0>, <&lpass_rx_macro 0>;
+ };
+ };
+
+ dai-link@1 {
+ link-name = "DisplayPort";
+ reg = <1>;
+
+ cpu {
+ sound-dai = <&lpass_cpu LPASS_DP_RX>;
+ };
+
+ codec {
+ sound-dai = <&mdss_dp>;
+ };
+ };
+
+ dai-link@2 {
+ link-name = "WCD9380 Capture";
+ reg = <2>;
+
+ cpu {
+ sound-dai = <&lpass_cpu LPASS_CDC_DMA_TX3>;
+ };
+
+ codec {
+ sound-dai = <&wcd938x 1>, <&swr1 0>, <&lpass_tx_macro 0>;
+ };
+ };
+};
--
2.53.0