Kyle Swenson | 8d8f654 | 2021-03-15 11:02:55 -0600 | [diff] [blame] | 1 | |
| 2 | Video Output Switcher Control |
| 3 | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| 4 | 2006 luming.yu@intel.com |
| 5 | |
| 6 | The output sysfs class driver provides an abstract video output layer that |
| 7 | can be used to hook platform specific methods to enable/disable video output |
| 8 | device through common sysfs interface. For example, on my IBM ThinkPad T42 |
| 9 | laptop, The ACPI video driver registered its output devices and read/write |
| 10 | method 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 | |