| |
| Video Output Switcher Control |
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| 2006 luming.yu@intel.com |
| |
| The output sysfs class driver provides an abstract video output layer that |
| can be used to hook platform specific methods to enable/disable video output |
| device through common sysfs interface. For example, on my IBM ThinkPad T42 |
| laptop, The ACPI video driver registered its output devices and read/write |
| method for 'state' with output sysfs class. The user interface under sysfs is: |
| |
| linux:/sys/class/video_output # tree . |
| . |
| |-- CRT0 |
| | |-- device -> ../../../devices/pci0000:00/0000:00:01.0 |
| | |-- state |
| | |-- subsystem -> ../../../class/video_output |
| | `-- uevent |
| |-- DVI0 |
| | |-- device -> ../../../devices/pci0000:00/0000:00:01.0 |
| | |-- state |
| | |-- subsystem -> ../../../class/video_output |
| | `-- uevent |
| |-- LCD0 |
| | |-- device -> ../../../devices/pci0000:00/0000:00:01.0 |
| | |-- state |
| | |-- subsystem -> ../../../class/video_output |
| | `-- uevent |
| `-- TV0 |
| |-- device -> ../../../devices/pci0000:00/0000:00:01.0 |
| |-- state |
| |-- subsystem -> ../../../class/video_output |
| `-- uevent |
| |