I am using an ASUS laptop with the dual nvidia/intel video cards and am trying to disable the nvidia card to save battery power. I am able to use the vga_switcheroo tool successfully when I boot using 22.214.171.124-0.fc15.x86_64, but when running 126.96.36.199-5.fc15.x86_64 the moment I run
echo OFF > /sys/kernel/debug/vgaswitcheroo/switch
it causes my system to hard lock to the point I have to power down. This is the same command I issue using the other kernel I mentioned and it works flawlessly.
Below I will include what have been able to pull from dmseg, the first example is from the successful kernel, the second is when it fails.
[ 85.877156] VGA switcheroo: switched nouveau off
[ 85.877246] [drm] nouveau 0000:01:00.0: Disabling fbcon acceleration...
[ 85.877252] [drm] nouveau 0000:01:00.0: Unpinning framebuffer(s)...
[ 85.877326] [drm] nouveau 0000:01:00.0: Evicting buffers...
[ 85.888567] [drm] nouveau 0000:01:00.0: Idling channels...
[ 85.888662] [drm] nouveau 0000:01:00.0: Suspending GPU objects...
[ 86.093746] [drm] nouveau 0000:01:00.0: And we're gone!
[ 86.093806] nouveau 0000:01:00.0: PCI INT A disabled
[ 86.095040] nouveau 0000:01:00.0: power state changed by ACPI to D3
[ 2.860925] vga_switcheroo: enabled
[ 2.860942] vgaarb: device changed decodes: PCI:0000:01:00.0,olddecodes=io+mem,decodes=none:ow ns=none
[ 2.860946] vgaarb: device changed decodes: PCI:0000:00:02.0,olddecodes=io+mem,decodes=none:ow ns=io+mem
[ 2.884439] Refined TSC clocksource calibration: 2294.787 MHz.
[ 2.884443] Switching to clocksource tsc
When the system freezes it starts scrolling text across the screen faster than I can read, but from what I can tell it mentions the nvidia driver (nouveau) and perhaps frame buffer? (fbcon)
Both Kernels are stock from the repository and were not custom compiled by me, they both have one non standard kernel module added (rts5139) for a 5 in 1 card reader.
Below are my video adapters as seen by lspci, just curious if anyone had any ideas?
00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09)
01:00.0 VGA compatible controller: nVidia Corporation GF106 [GeForce GT 555M SDDR3] (rev a1)