projects / mirror_ubuntu-bionic-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 3c4c1b69 CC |
1 | What: /sys/class/backlight/<backlight>/bl_power |
| 2 | Date: April 2005 | |
| 3 | KernelVersion: 2.6.12 | |
| 4 | Contact: Richard Purdie <rpurdie@rpsys.net> | |
| 5 | Description: | |
| 6 | Control BACKLIGHT power, values are FB_BLANK_* from fb.h | |
| 7 | - FB_BLANK_UNBLANK (0) : power on. | |
| 8 | - FB_BLANK_POWERDOWN (4) : power off | |
| 9 | Users: HAL | |
| 10 | ||
| 11 | What: /sys/class/backlight/<backlight>/brightness | |
| 12 | Date: April 2005 | |
| 13 | KernelVersion: 2.6.12 | |
| 14 | Contact: Richard Purdie <rpurdie@rpsys.net> | |
| 15 | Description: | |
| 16 | Control the brightness for this <backlight>. Values | |
| 17 | are between 0 and max_brightness. This file will also | |
| 18 | show the brightness level stored in the driver, which | |
| 19 | may not be the actual brightness (see actual_brightness). | |
| 20 | Users: HAL | |
| 21 | ||
| 22 | What: /sys/class/backlight/<backlight>/actual_brightness | |
| 23 | Date: March 2006 | |
| 24 | KernelVersion: 2.6.17 | |
| 25 | Contact: Richard Purdie <rpurdie@rpsys.net> | |
| 26 | Description: | |
| 27 | Show the actual brightness by querying the hardware. | |
| 28 | Users: HAL | |
| 29 | ||
| 30 | What: /sys/class/backlight/<backlight>/max_brightness | |
| 31 | Date: April 2005 | |
| 32 | KernelVersion: 2.6.12 | |
| 33 | Contact: Richard Purdie <rpurdie@rpsys.net> | |
| 34 | Description: | |
| 35 | Maximum brightness for <backlight>. | |
| 36 | Users: HAL | |
| bb7ca747 MG |
37 | |
| 38 | What: /sys/class/backlight/<backlight>/type | |
| 39 | Date: September 2010 | |
| 40 | KernelVersion: 2.6.37 | |
| 41 | Contact: Matthew Garrett <mjg@redhat.com> | |
| 42 | Description: | |
| 43 | The type of interface controlled by <backlight>. | |
| 44 | "firmware": The driver uses a standard firmware interface | |
| 45 | "platform": The driver uses a platform-specific interface | |
| 46 | "raw": The driver controls hardware registers directly | |
| 47 | ||
| 48 | In the general case, when multiple backlight | |
| 49 | interfaces are available for a single device, firmware | |
| 50 | control should be preferred to platform control should | |
| 51 | be preferred to raw control. Using a firmware | |
| 52 | interface reduces the probability of confusion with | |
| 53 | the hardware and the OS independently updating the | |
| 54 | backlight state. Platform interfaces are mostly a | |
| 55 | holdover from pre-standardisation of firmware | |
| 56 | interfaces. |