sound/soc/codec-to-codec.rst

2 Creating codec to codec dai link for ALSA dapm
9    ---------          ---------
10   |         |  dai   |         |
11       CPU    ------->    codec
13    ---------          ---------
18                        ---------
20                         codec-2
22                       ---------
24                          dai-2
26    ----------          ---------
27   |          |  dai-1 |         |
28       CPU     ------->  codec-1
30    ----------          ---------
32                          dai-3
34                        ---------
36                         codec-3
38                        ---------
40 Suppose codec-2 is a bluetooth chip and codec-3 is connected to
42 codec-2 will receive the audio data and the user wants to play that
43 audio through codec-3 without involving the CPU.This
45 connection should be used.
64     .name = "CPU-DSP",
65     .stream_name = "CPU-DSP",
66     .cpu_dai_name = "samsung-i2s.0",
67     .codec_name = "codec-2,
68     .codec_dai_name = "codec-2-dai_name",
69     .platform_name = "samsung-i2s.0",
76     .name = "DSP-CODEC",
77     .stream_name = "DSP-CODEC",
78     .cpu_dai_name = "wm0010-sdi2",
79     .codec_name = "codec-3,
80     .codec_dai_name = "codec-3-dai_name",
93 and codec_dai capture widget for playback path and vice-versa is
95 triggered, DAPM needs to find a valid endpoint which could be either
100 the speaker amp can be created as demonstrated in wm8727.c file, it
104 dai names ending with "Playback" and "Capture" respectively as dapm core
105 will link and power those dais based on the name.
107 A dai_link in a "simple-audio-card" will automatically be detected as
108 codec to codec when all DAIs on the link belong to codec components.
109 The dai_link will be initialized with the subset of stream parameters
110 (channels, format, sample rate) supported by all DAIs on the link. Since
112 mostly useful for communication with simple fixed-function codecs, such