Documentation/devicetree/bindings/sound/audio-graph-card.txt

   1 Audio Graph Card:
   2
   3 Audio Graph Card specifies audio DAI connections of SoC <-> codec.
   4 It is based on common bindings for device graphs.
   5 see ${LINUX}/Documentation/devicetree/bindings/graph.txt
   6
   7 Basically, Audio Graph Card property is same as Simple Card.
   8 see ${LINUX}/Documentation/devicetree/bindings/sound/simple-card.txt
   9
  10 Below are same as Simple-Card.
  11
  12 - label
  13 - widgets
  14 - routing
  15 - dai-format
  16 - frame-master
  17 - bitclock-master
  18 - bitclock-inversion
  19 - frame-inversion
  20 - mclk-fs
  21 - hp-det-gpio
  22 - mic-det-gpio
  23 - dai-tdm-slot-num
  24 - dai-tdm-slot-width
  25 - clocks / system-clock-frequency
  26
  27 Required properties:
  28
  29 - compatible                            : "audio-graph-card";
  30 - dais                                  : list of CPU DAI port{s}
  31
  32 Optional properties:
  33 - pa-gpios: GPIO used to control external amplifier.
  34
  35 Example: Single DAI case
  36
  37         sound_card {
  38                 compatible = "audio-graph-card";
  39
  40                 dais = <&cpu_port>;
  41         };
  42
  43         dai-controller {
  44                 ...
  45                 cpu_port: port {
  46                         cpu_endpoint: endpoint {
  47                                 remote-endpoint = <&codec_endpoint>;
  48
  49                                 dai-format = "left_j";
  50                                 ...
  51                         };
  52                 };
  53         };
  54
  55         audio-codec {
  56                 ...
  57                 port {
  58                         codec_endpoint: endpoint {
  59                                 remote-endpoint = <&cpu_endpoint>;
  60                         };
  61                 };
  62         };
  63
  64 Example: Multi DAI case
  65
  66         sound-card {
  67                 compatible = "audio-graph-card";
  68
  69                 label = "sound-card";
  70
  71                 dais = <&cpu_port0
  72                         &cpu_port1
  73                         &cpu_port2>;
  74         };
  75
  76         audio-codec@0 {
  77                 ...
  78                 port {
  79                         codec0_endpoint: endpoint {
  80                                 remote-endpoint = <&cpu_endpoint0>;
  81                         };
  82                 };
  83         };
  84
  85         audio-codec@1 {
  86                 ...
  87                 port {
  88                         codec1_endpoint: endpoint {
  89                                 remote-endpoint = <&cpu_endpoint1>;
  90                         };
  91                 };
  92         };
  93
  94         audio-codec@2 {
  95                 ...
  96                 port {
  97                         codec2_endpoint: endpoint {
  98                                 remote-endpoint = <&cpu_endpoint2>;
  99                         };
 100                 };
 101         };
 102
 103         dai-controller {
 104                 ...
 105                 ports {
 106                         cpu_port0: port@0 {
 107                                 cpu_endpoint0: endpoint {
 108                                         remote-endpoint = <&codec0_endpoint>;
 109
 110                                         dai-format = "left_j";
 111                                         ...
 112                                 };
 113                         };
 114                         cpu_port1: port@1 {
 115                                 cpu_endpoint1: endpoint {
 116                                         remote-endpoint = <&codec1_endpoint>;
 117
 118                                         dai-format = "i2s";
 119                                         ...
 120                                 };
 121                         };
 122                         cpu_port2: port@2 {
 123                                 cpu_endpoint2: endpoint {
 124                                         remote-endpoint = <&codec2_endpoint>;
 125
 126                                         dai-format = "i2s";
 127                                         ...
 128                                 };
 129                         };
 130                 };
 131         };
 132