I did not do something streamlined like using a tool or something. I just reversed the nvidia driver in vista. I am not sure if there is any point in describing the process here. There are tons of info on reverse engineering on the net, but here is a general description.
After failing to spot any changes in the documented registers that are dumped by RivaTuner (after even extending the ranges) I had to take it more seriously. I attached WinDbg (the Windows kernel debugger) from a remote pc via firewire and traced through the windows kernel and nvidia driver, by examining the dissasembled code (using IDA Pro) and the memory and by putting breakpoints here and there. I found the address that is modified and caused the backlight level to change. After that you need to convert this virtual address to a physical bus address in order to use it from another operating system (or even the same system under different circumstances). I booted linux, modified the nvclock backend to write values to the new video memory location and voila! Have in mind that reversing commercial software like the Nvidia drivers is illegal. Michael On Tue, Oct 21, 2008 at 1:29 PM, Michael Doube <[EMAIL PROTECTED]> wrote: > mikes: could you please detail the method that you used to discover the > registers so that others may do this on future iterations and possibly > other manufacturers' implementations of nVidia devices? The basic > problem here was that no-one had a clue how to get the information that > you have discovered. > > -- > No Screen Backlight Control; Sony Vaio with nvidia 8 series graphics > https://bugs.launchpad.net/bugs/95444 > You received this bug notification because you are a direct subscriber > of the bug. > > Status in "hotkey-setup" source package in Ubuntu: In Progress > Status in "linux" source package in Ubuntu: In Progress > Status in "nvidia-graphics-drivers-177" source package in Ubuntu: In > Progress > > Bug description: > Using Ubuntu on Sony Vaio laptop with Nvidia 8 vga card: > > There is no way to control backlight brightness on Sony Vaios with 8-series > adapters, e.g. > nVidia Corporation GeForce 8400M GS > nVidia Corporation GeForce 8600M GT (rev a1) > > The registers have been found (kudos to mikes!). See these hacked nvclock > sources for fixed versions which can set backlight on Sony Vaios: > > http://stud.matrixcode.de/nvclock_hacked_seek.tgz > http://launchpadlibrarian.net/18755253/nvclock_hacked.tgz > > So far mikes' registers have been found to work on: > 8400M GS on Vaio SZ650 > 8400M GT on Vaio FZ38M, FZ11Z > 8600M GS on Vaio FZ31Z > > Invoking sonybright.sh with hotkeys will do nothing until the script calls > new versions either SmartDimmer or nvclock properly. > > Dual-adapter models (SZ6 among others) can get backlight control with the > Intel adapter using xbacklight, and can get hotkey functionality as per bug > #173652. > -- No Screen Backlight Control; Sony Vaio with nvidia 8 series graphics https://bugs.launchpad.net/bugs/95444 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
