Documentation/devicetree/bindings/sound/st,stm32-adfsdm.txt

   1 STMicroelectronics Audio Digital Filter Sigma Delta modulators(DFSDM)
   2
   3 The DFSDM allows PDM microphones capture through SPI interface. The Audio
   4 interface is seems as a sub block of the DFSDM device.
   5 For details on DFSDM bindings refer to ../iio/adc/st,stm32-dfsdm-adc.txt
   6
   7 Required properties:
   8   - compatible: "st,stm32h7-dfsdm-dai".
   9
  10   - #sound-dai-cells : Must be equal to 0
  11
  12   - io-channels : phandle to iio dfsdm instance node.
  13
  14 Example of a sound card using audio DFSDM node.
  15
  16         sound_card {
  17                 compatible = "audio-graph-card";
  18
  19                 dais = <&cpu_port>;
  20         };
  21
  22         dfsdm: dfsdm@40017000 {
  23                 compatible = "st,stm32h7-dfsdm";
  24                 reg = <0x40017000 0x400>;
  25                 clocks = <&rcc DFSDM1_CK>;
  26                 clock-names = "dfsdm";
  27                 #interrupt-cells = <1>;
  28                 #address-cells = <1>;
  29                 #size-cells = <0>;
  30
  31                 dfsdm_adc0: filter@0 {
  32                         compatible = "st,stm32-dfsdm-dmic";
  33                         reg = <0>;
  34                         interrupts = <110>;
  35                         dmas = <&dmamux1 101 0x400 0x00>;
  36                         dma-names = "rx";
  37                         st,adc-channels = <1>;
  38                         st,adc-channel-names = "dmic0";
  39                         st,adc-channel-types = "SPI_R";
  40                         st,adc-channel-clk-src = "CLKOUT";
  41                         st,filter-order = <5>;
  42
  43                         dfsdm_dai0: dfsdm-dai {
  44                                 compatible = "st,stm32h7-dfsdm-dai";
  45                                 #sound-dai-cells = <0>;
  46                                 io-channels = <&dfsdm_adc0 0>;
  47                                 cpu_port: port {
  48                                 dfsdm_endpoint: endpoint {
  49                                         remote-endpoint = <&dmic0_endpoint>;
  50                                 };
  51                         };
  52                 };
  53         };
  54
  55         dmic0: dmic@0 {
  56                 compatible = "dmic-codec";
  57                 #sound-dai-cells = <0>;
  58                 port {
  59                         dmic0_endpoint: endpoint {
  60                                 remote-endpoint = <&dfsdm_endpoint>;
  61                         };
  62                 };
  63         };