linux/Documentation/video-output.txt
<<
>>
Prefs
   1Video Output Switcher Control
   2~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   3
   42006 luming.yu@intel.com
   5
   6The output sysfs class driver provides an abstract video output layer that
   7can be used to hook platform specific methods to enable/disable video output
   8device through common sysfs interface. For example, on my IBM ThinkPad T42
   9laptop, The ACPI video driver registered its output devices and read/write
  10method for 'state' with output sysfs class. The user interface under sysfs is::
  11
  12  linux:/sys/class/video_output # tree .
  13  .
  14  |-- CRT0
  15  |   |-- device -> ../../../devices/pci0000:00/0000:00:01.0
  16  |   |-- state
  17  |   |-- subsystem -> ../../../class/video_output
  18  |   `-- uevent
  19  |-- DVI0
  20  |   |-- device -> ../../../devices/pci0000:00/0000:00:01.0
  21  |   |-- state
  22  |   |-- subsystem -> ../../../class/video_output
  23  |   `-- uevent
  24  |-- LCD0
  25  |   |-- device -> ../../../devices/pci0000:00/0000:00:01.0
  26  |   |-- state
  27  |   |-- subsystem -> ../../../class/video_output
  28  |   `-- uevent
  29  `-- TV0
  30     |-- device -> ../../../devices/pci0000:00/0000:00:01.0
  31     |-- state
  32     |-- subsystem -> ../../../class/video_output
  33     `-- uevent
  34
  35