Documentation/devicetree/bindings/iio/adc/envelope-detector.txt

   1 Bindings for ADC envelope detector using a DAC and a comparator
   2
   3 The DAC is used to find the peak level of an alternating voltage input
   4 signal by a binary search using the output of a comparator wired to
   5 an interrupt pin. Like so:
   6                           _
   7                          | \
   8     input +------>-------|+ \
   9                          |   \
  10            .-------.     |    }---.
  11            |       |     |   /    |
  12            |    dac|-->--|- /     |
  13            |       |     |_/      |
  14            |       |              |
  15            |       |              |
  16            |    irq|------<-------'
  17            |       |
  18            '-------'
  19
  20 Required properties:
  21 - compatible: Should be "axentia,tse850-envelope-detector"
  22 - io-channels: Channel node of the dac to be used for comparator input.
  23 - io-channel-names: Should be "dac".
  24 - interrupt specification for one client interrupt,
  25   see ../../interrupt-controller/interrupts.txt for details.
  26 - interrupt-names: Should be "comp".
  27
  28 Example:
  29
  30         &i2c {
  31                 dpot: mcp4651-104@28 {
  32                         compatible = "microchip,mcp4651-104";
  33                         reg = <0x28>;
  34                         #io-channel-cells = <1>;
  35                 };
  36         };
  37
  38         dac: dac {
  39                 compatible = "dpot-dac";
  40                 vref-supply = <&reg_3v3>;
  41                 io-channels = <&dpot 0>;
  42                 io-channel-names = "dpot";
  43                 #io-channel-cells = <1>;
  44         };
  45
  46         envelope-detector {
  47                 compatible = "axentia,tse850-envelope-detector";
  48                 io-channels = <&dac 0>;
  49                 io-channel-names = "dac";
  50
  51                 interrupt-parent = <&gpio>;
  52                 interrupts = <3 IRQ_TYPE_EDGE_FALLING>;
  53                 interrupt-names = "comp";
  54         };