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