More Generic Audio Graph Sound Card idea

[Kuninori Morimoto]

Hi ALSA ML


> I'm thinking below style as new audio-graph-card2.
> It is not tricky, thus connection judgement for normal vs DSP is easy.
> Then, code can be more readable (= no guaranty :P) ?

I have proposed DPCM connection idea for audio-card2 before,
and proposed Multi-CPU/Codec connection idea later.
I'm not yet implemented these, but I want to merge / reuse these
idea to keep simple code.

By this mail, I want to propose Codec2Codec idea.
It is almost same idea with DPCM, Multi-CPU/Codec,
and is last parts for missing feature.

I think this idea can be generic and easy to update
in the future (if needed).

But, I want feedback, opinion.
I wonder does it works for your use-case ?

-- Image ---

Codec2Codec

Codec1 <--> Codec2

-- DT Image --

   +--+
=> |  |<--> Codec1
   |  |<--> Codec2
   +--+

-- DT Sample --

	sound {
		compatible = "audio-graph-card2";

		dais = <&codec2codec>;
	};

	CODEC2CODEC {
		compatible = "audio-graph-card2-codec2codec";

		ports {
			codec2codec: port at 0 { fe_ep: endpoint { remote-endpoint = <&codec1_ep>; }; };
			             port at 1 { be_ep: endpoint { remote-endpoint = <&codec2_ep>; }; };
		};
	};

 	Codec1 {
		port at 0 { codec1_ep: endpoint { remote-endpoint = <&fe_ep>; }; };
	};

 	Codec2 {
		port at 0 { codec2_ep: endpoint { remote-endpoint = <&be_ep>; }; };
	};


-- Image ---

          *******
PCM0 <--> *     * <--> DAI0: Codec Headset
PCM1 <--> *     * <--> DAI1: Codec Speakers
PCM2 <--> * DSP * <--> DAI2: MODEM
PCM3 <--> *     * <--> DAI3: BT
          *     * <--> DAI4: DMIC
          *     * <--> DAI5: FM
          *******

-- DT Image --

   +--+                ****                 +--+
=> |  |<--> PCM0       *  * <-- (dummy) --> |  | <=
   |  |<-- (dummy) --> *  *       DAI0 <--> |  |
   +--+                *  *                 +--+
                       *  *            
   +--+                *  *                 +--+
=> |  |<--> PCM1       *  * <-- (dummy) --> |  | <=
   |  |<-- (dummy) --> *  *       DAI1 <--> |  |
   +--+                *  *                 +--+
   ...                 ...                 ...


-- DT Sample --

	sound {
		compatible = "audio-graph-card2";

		/* indicate all Front-End, Back-End in DPCM case */
		dais = <&dsp_fe0, &dsp_fe1, &dsp_fe2, &dsp_fe3,
		        &dsp_be0, &dsp_be1, &dsp_be2, &dsp_be3, &dsp_be4, &dsp_be5>;
	};

	DSP {
		compatible = "audio-graph-card2-dsp";

		ports at 0 {
			/* Front-End is pcm0_ep, Back-End is dummy */
			dsp_fe0: port at 0 { dsp_fe0_ep: endpoint { remote-endpoint = <&pcm0_ep>; }; };
			         port at 1 { };
		};

		...

		ports at 4 {
			/* Front-End is dummy, Back-End is dai_ep */
			dsp_be0: port at 0 { };
			         port at 1 { dsp_be0_ep: endpoint { remote-endpoint = <&dai0_ep>; }; };
		};

		...

	};

 	CPU {
		ports {
			port at 0 { pcm0_ep: endpoint { remote-endpoint = <&dsp_fe0_ep>; }; };
			port at 1 { pcm1_ep: endpoint { remote-endpoint = <&dsp_fe1_ep>; }; };
			port at 2 { pcm2_ep: endpoint { remote-endpoint = <&dsp_fe2_ep>; }; };
			port at 3 { pcm3_ep: endpoint { remote-endpoint = <&dsp_fe3_ep>; }; };
			...
		};
	};

	Codec {
		ports {
			port at 0 { dai0_ep: endpoint { remote-endpoint = <&dsp_be0_ep>; }; };
			port at 1 { dai1_ep: endpoint { remote-endpoint = <&dsp_be1_ep>; }; };
			port at 2 { dai2_ep: endpoint { remote-endpoint = <&dsp_be2_ep>; }; };
			port at 3 { dai3_ep: endpoint { remote-endpoint = <&dsp_be3_ep>; }; };
			port at 4 { dai4_ep: endpoint { remote-endpoint = <&dsp_be4_ep>; }; };
			port at 5 { dai5_ep: endpoint { remote-endpoint = <&dsp_be5_ep>; }; };
			...
		};
	};


-- Image ---

As Sample, Normal Audio-Graph

CPU <---> Codec (Same as before)

-- DT Sample --

	sound {
		compatible = "audio-graph-card2";

		dais = <&cpu>;
	};

	CPU {
		cpu: port { cpu_ep: endpoint { remote-endpoint = <&codec_ep>; }; };
	};

	Codec {
		codec: port { codec_ep: endpoint { remote-endpoint = <&cpu_ep>; }; };
	};


-- Image ---

Multi-CPU/Codec
(complex connection as sample)

<- multi_CPU_0 ->
           ******
CPU01 <--> *    * <--> Codec0
       \-> *    *
CPU02 <--> *    *
           ******

           <-- multi_codec_1 -->
          ******
CPU1 <--> *    * <--> Codec11
          *    * <-/
          *    * <--> Codec12
          ******

-- DT Image --

   +--+                     +--+
=> |  | <--> CPU01_1     => |  | <--> CPU1
   |  | <--> CPU01_2        |  |
   |  | <--> CPU02          |  | <--> Codec11_1
   |  |                     |  | <--> Codec11_2
   |  | <--> Codec0         |  | <--> Codec12
   +--+                     +--+

-- DT Sample --

	sound {
		compatible = "audio-graph-card2";

		dais = <&cpu_0,
		        &cpu_1>;
	};

	MULTI0 {
		compatible = "audio-graph-card2-multi";

		cpu_0: ports at 0 {
			port at 0 { fe0_1_ep: endpoint { remote-endpoint = <&cpu01_1_ep>; }; };
			port at 1 { fe0_2_ep: endpoint { remote-endpoint = <&cpu01_2_ep>; }; };
			port at 2 { fe0_3_ep: endpoint { remote-endpoint = <&cpu02_ep>; }; };
		};
		ports at 1 {
			port at 0 { be0_ep: endpoint { remote-endpoint = <&codec0_ep>; }; };
		};
	};

	MULTI1 {
		compatible = "audio-graph-card2-multi";

		cpu_1: ports at 0 {
			port at 0 { fe1_ep: endpoint { remote-endpoint = <&cpu1_ep>; }; };
		};
		ports at 1 {
			port at 0 { be1_1_ep: endpoint { remote-endpoint = <&codec11_1_ep>; }; };
			port at 1 { be1_2_ep: endpoint { remote-endpoint = <&codec11_2_ep>; }; };
			port at 2 { be1_3_ep: endpoint { remote-endpoint = <&codec12_ep>; }; };
		};
	};

	CPU01 {
		ports {
			port at 0 { cpu01_1_ep: endpoint { remote-endpoint = <&fe0_1_ep>; }; };
			port at 1 { cpu01_2_ep: endpoint { remote-endpoint = <&fe0_2_ep>; }; };
			...
		};
	};

	CPU02 {
		ports {
			port at 0 { cpu02_ep: endpoint { remote-endpoint = <&fe0_3_ep>; }; };
			...
		};
	};

	CPU1 {
		ports {
			port at 0 { cpu1_ep: endpoint { remote-endpoint = <&fe1_ep>; }; };
			...
		};
	};

	Codec0 {
		ports {
			port at 0 { codec0_ep: endpoint { remote-endpoint = <&be0_ep>; }; };
			port at 1 { ... };
		};
	};

	Codec11 {
		ports {
			port at 0 { codec11_1_ep: endpoint { remote-endpoint = <&be1_1_ep>; }; };
			port at 1 { codec11_2_ep: endpoint { remote-endpoint = <&be1_2_ep>; }; };
			port at 2 { ... };
		};
	};

	Codec12 {
		ports {
			port at 0 { codec12_ep: endpoint { remote-endpoint = <&be1_3_ep>; }; };
			port at 1 { ... };
		};
	};