Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) ====================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) ASoC Platform Driver
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3) ====================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5) An ASoC platform driver class can be divided into audio DMA drivers, SoC DAI
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6) drivers and DSP drivers. The platform drivers only target the SoC CPU and must
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) have no board specific code.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) Audio DMA
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) =========
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) The platform DMA driver optionally supports the following ALSA operations:-
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) ::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)   /* SoC audio ops */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16)   struct snd_soc_ops {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 	int (*startup)(struct snd_pcm_substream *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 	void (*shutdown)(struct snd_pcm_substream *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 	int (*hw_params)(struct snd_pcm_substream *, struct snd_pcm_hw_params *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 	int (*hw_free)(struct snd_pcm_substream *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 	int (*prepare)(struct snd_pcm_substream *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 	int (*trigger)(struct snd_pcm_substream *, int);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23)   };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) The platform driver exports its DMA functionality via struct
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) snd_soc_component_driver:-
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) ::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29)   struct snd_soc_component_driver {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 	const char *name;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 	...
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 	int (*probe)(struct snd_soc_component *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 	void (*remove)(struct snd_soc_component *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 	int (*suspend)(struct snd_soc_component *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 	int (*resume)(struct snd_soc_component *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 	/* pcm creation and destruction */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 	int (*pcm_new)(struct snd_soc_pcm_runtime *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 	void (*pcm_free)(struct snd_pcm *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 	...
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 	const struct snd_pcm_ops *ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 	const struct snd_compr_ops *compr_ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 	...
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)   };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) Please refer to the ALSA driver documentation for details of audio DMA.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) http://www.alsa-project.org/~iwai/writing-an-alsa-driver/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) An example DMA driver is soc/pxa/pxa2xx-pcm.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) SoC DAI Drivers
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) ===============
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) Each SoC DAI driver must provide the following features:-
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 1. Digital audio interface (DAI) description
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 2. Digital audio interface configuration
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 3. PCM's description
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 4. SYSCLK configuration
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 5. Suspend and resume (optional)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) Please see codec.rst for a description of items 1 - 4.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) SoC DSP Drivers
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) ===============
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) Each SoC DSP driver usually supplies the following features :-
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 1. DAPM graph
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 2. Mixer controls
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) 3. DMA IO to/from DSP buffers (if applicable)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) 4. Definition of DSP front end (FE) PCM devices.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) Please see DPCM.txt for a description of item 4.