arch/arm64/boot/dts/renesas/ulcb-audio-graph-card2-mix+split.dtsi

Source file repositories/reference/linux-study-clean/arch/arm64/boot/dts/renesas/ulcb-audio-graph-card2-mix+split.dtsi

File Facts

System
Linux kernel
Corpus path
arch/arm64/boot/dts/renesas/ulcb-audio-graph-card2-mix+split.dtsi
Extension
.dtsi
Size
2072 bytes
Lines
113
Domain
Architecture Layer
Bucket
arch/arm64
Inferred role
Architecture Layer: configuration, schema, or hardware description
Status
atlas-only

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
/*
 * Device Tree for ULCB + Audio Graph Card2 (MIX + TDM Split)
 *
 * Copyright (C) 2022 Renesas Electronics Corp.
 */

/*
 * Note:
 * The HDMI output is ignored due to the limited number of subdevices
 *
 *	(A) CPU0 (2ch) <----> (2ch) (X) ak4613	(MIX-0)
 *	(B) CPU1 (2ch)  --/			(MIX-1)
 *
 *	(A) aplay   -D plughw:0,0 xxx.wav
 *	(B) aplay   -D plughw:0,1 xxx.wav
 *
 *	(A) arecord -D plughw:0,0 xxx.wav
 */
/ {
	sound_card: sound {
		compatible = "audio-graph-card2";
		label = "snd-ulcb-mix";

		routing = "ak4613 Playback", "DAI0 Playback",
			  "ak4613 Playback", "DAI1 Playback",
			  "DAI0 Capture",    "ak4613 Capture";

		links = <&fe_a		/* (A) CPU0   */
			 &fe_b		/* (B) CPU1   */
			 &be_x		/* (X) ak4613 */
		>;

		dpcm {
			#address-cells = <1>;
			#size-cells = <0>;

			ports@0 {
				#address-cells = <1>;
				#size-cells = <0>;
				reg = <0>;
				/*
				 * FE
				 * (A) CPU0 (MIX-0)
				 * (B) CPU1 (MIX-1)
				 */
				fe_a: port@0 { reg = <0>; fe_a_ep: endpoint { remote-endpoint = <&rsnd_a_ep>; }; };
				fe_b: port@1 { reg = <1>; fe_b_ep: endpoint { remote-endpoint = <&rsnd_b_ep>; }; };
			};

			ports@1 {
				reg = <1>;
				/*
				 * BE
				 * (X) ak4613
				 */
				be_x: port { be_x_ep: endpoint { remote-endpoint = <&ak4613_x_ep>; }; };
			};
		};
	};
};

&ak4613 {
	port {
		/*
		 * (X) ak4613
		 */
		prefix = "ak4613";
		convert-rate = <48000>;

Annotation

Implementation Notes