ti-tsc-adc.txt 1.5 KB

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  1. * TI - TSC ADC (Touschscreen and analog digital converter)
  2. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  3. Required properties:
  4. - child "tsc"
  5. ti,wires: Wires refer to application modes i.e. 4/5/8 wire touchscreen
  6. support on the platform.
  7. ti,x-plate-resistance: X plate resistance
  8. ti,coordiante-readouts: The sequencer supports a total of 16
  9. programmable steps each step is used to
  10. read a single coordinate. A single
  11. readout is enough but multiple reads can
  12. increase the quality.
  13. A value of 5 means, 5 reads for X, 5 for
  14. Y and 2 for Z (always). This utilises 12
  15. of the 16 software steps available. The
  16. remaining 4 can be used by the ADC.
  17. ti,wire-config: Different boards could have a different order for
  18. connecting wires on touchscreen. We need to provide an
  19. 8 bit number where in the 1st four bits represent the
  20. analog lines and the next 4 bits represent positive/
  21. negative terminal on that input line. Notations to
  22. represent the input lines and terminals resoectively
  23. is as follows:
  24. AIN0 = 0, AIN1 = 1 and so on till AIN7 = 7.
  25. XP = 0, XN = 1, YP = 2, YN = 3.
  26. - child "adc"
  27. ti,adc-channels: List of analog inputs available for ADC.
  28. AIN0 = 0, AIN1 = 1 and so on till AIN7 = 7.
  29. Example:
  30. tscadc: tscadc@44e0d000 {
  31. compatible = "ti,am3359-tscadc";
  32. tsc {
  33. ti,wires = <4>;
  34. ti,x-plate-resistance = <200>;
  35. ti,coordiante-readouts = <5>;
  36. ti,wire-config = <0x00 0x11 0x22 0x33>;
  37. };
  38. adc {
  39. ti,adc-channels = <4 5 6 7>;
  40. };
  41. }