video_extension.txt 1.5 KB

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  1. ACPI video extensions
  2. ~~~~~~~~~~~~~~~~~~~~~
  3. This driver implement the ACPI Extensions For Display Adapters for
  4. integrated graphics devices on motherboard, as specified in ACPI 2.0
  5. Specification, Appendix B, allowing to perform some basic control like
  6. defining the video POST device, retrieving EDID information or to
  7. setup a video output, etc. Note that this is an ref. implementation
  8. only. It may or may not work for your integrated video device.
  9. Interfaces exposed to userland through /proc/acpi/video:
  10. VGA/info : display the supported video bus device capability like Video ROM, CRT/LCD/TV.
  11. VGA/ROM : Used to get a copy of the display devices' ROM data (up to 4k).
  12. VGA/POST_info : Used to determine what options are implemented.
  13. VGA/POST : Used to get/set POST device.
  14. VGA/DOS : Used to get/set ownership of output switching:
  15. Please refer ACPI spec B.4.1 _DOS
  16. VGA/CRT : CRT output
  17. VGA/LCD : LCD output
  18. VGA/TVO : TV output
  19. VGA/*/brightness : Used to get/set brightness of output device
  20. Notify event through /proc/acpi/event:
  21. #define ACPI_VIDEO_NOTIFY_SWITCH 0x80
  22. #define ACPI_VIDEO_NOTIFY_PROBE 0x81
  23. #define ACPI_VIDEO_NOTIFY_CYCLE 0x82
  24. #define ACPI_VIDEO_NOTIFY_NEXT_OUTPUT 0x83
  25. #define ACPI_VIDEO_NOTIFY_PREV_OUTPUT 0x84
  26. #define ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS 0x82
  27. #define ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS 0x83
  28. #define ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS 0x84
  29. #define ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS 0x85
  30. #define ACPI_VIDEO_NOTIFY_DISPLAY_OFF 0x86