Language Selection

English French German Italian Portuguese Spanish

Linux backlight control

Filed under

Backlight control is one of those things that you'd think would be simple, but ha ha this is computing so of course it's an utter disaster and everything is a huge mess. There's three main classes of backlight control in the x86 world, all of which have drawbacks:

* ACPI specifies a mechanism for backlight control, and the majority of modern machines implement it. It has the advantage that the brightness query interface is generally aware of anything else in the system which may have changed the brightness, so it's unlikely to get out of sync with reality if the platform tries to do something odd like change the backlight itself in response to an ambient light sensor or some other event. The main drawback is that there's typically a fairly small number of available backlight values, usually somewhere between 8 and 20.

* A platform-specific mechanism.

rest here

More in Tux Machines

Android Leftovers

LG releases webOS Open Source Edition, looks to expand webOS usage

LG’s smart TVs ship with an operating system called webOS, which is the latest version of an operating system that was developed by Palm to run on phones, acquired by HP to use with tablets, and eventually sold to LG, which is still using it today. But now LG wants to expand the adoption of webOS and the company is working with the South Korean government to solicit business proposals from other companies interested in using webOS. LG has also released a webOS Open Source Edition version of the operating system. Read more

Test driving 4 open source music players and more

In my last article, I described my latest music problem: I need an additional stage of amplification to make proper use of my new phono cartridge. While my pre-amplifier contains a phono stage, its gain is only suitable for cartridges that output about 5mV, whereas my new cartridge has a nominal output of 0.4mV. Based on my investigation, I liked the looks of the Muffsy phono kits, so I ordered the head amplifier, the power supply, and the back panel. I also needed to obtain a case to hold the boards and the back panel, available online from many vendors. Muffsy does not sell the “wall wart” necessary to power the unit, so I ordered one of those from a supplier in California. Finally, inspecting my soldering iron, solder “sucker,” and solder, I’ve realized I need to do better—so a bit more shopping, online or local, is in order there. Finally, for those, like me, whose soldering skills may be rusty and perhaps were not all that great to begin with, Muffsy kindly offers links to two instructional videos. Read more

Today in Techrights