https://bugzilla.kernel.org/show_bug.cgi?id=51381
--- Comment #22 from Teofilis Martisius Teofilis.Martisius@gmail.com --- Ok,
I tried playing around with Linux 3.12, that's the last stable version before that commit.
Booted with parameters:
[ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-3.12-1-amd64 root=UUID=... ro quiet radeon.audio=0 modeset=1 radeon.dpm=1 radeon.no_wb=1 radeon.runpm=0
Executed:
echo OFF >/sys/kernel/debug/vgaswitcheroo/switch
dGPU got switched off, everything works fine. Got a message in dmesg:
[ 1454.396648] radeon: switched off
I don't want to spam attachments on this bug report, full dmesg output if needed at: http://menulis.org/kernel/dmesg_3.12_off1.log
I tried it with radeon.runpm=1 as well, same results, everything works fine. Dmesg: http://menulis.org/kernel/dmesg_3.12_off2.log
Let me know if you want these two dmesg logs attached here in bugzilla.
Let me know if you need me to try something else next.
Sincerely, Teofilis Martisius