Since commit e646d57 booting my 15" MacbookPro results in a black screen. I don't believe this is related to the LVDS channels which was fixed a few commits previous, but a new issue. Please let me know if any additional information is needed.
Created attachment 61064 [details]
Created attachment 61065 [details]
Just to double check: With e646d57 you get a black screen and with the commit right before that (i.e. 7a39a9d4767e8d22) everything works smoothly? Also please boot with drm.debug=0xe added to your kernel cmdline on both a broken and a working kernel (preferrable the two sha1 versions mentioned above) and attach the complete dmesg for both runs.
Created attachment 61088 [details]
working dmesg output from 7a39a9d
Created attachment 61089 [details]
broken dmesg output from e646d57
Created attachment 61090 [details]
kernel config (same for both broken and working)
That's correct, 7a39a9d works great, e646d57 black screens. (Of course I didn't get lucky, i had to bisect :P ). Dmesg output attached as requested
Shot in the dark: Can you try the linked patch on top of drm-intel-next-queued?
Created attachment 61203 [details]
dmesg output booting with edp-power-sequencing-fix.patch
Created attachment 61204 [details]
intel_reg_dumper output booting with edp-power-sequencing-fix.patch
No dice unfortunately. Dmesg and intel_reg_dumper output attached.
Created attachment 61350 [details] [review]
don't return -ENXIO
Patch for you to try.
The latest patch works when applied on aa104eb! Thanks!
Created attachment 61885 [details] [review]
improved patch after review
Daniel Kurtz suggested a slightly alternative approach to fix this bug. Please test this new patch and check whether things still work out for you. Thanks.
The new patch works great too.
Patch merged to -fixes:
Author: Daniel Vetter <firstname.lastname@example.org>
Date: Mon May 21 20:19:48 2012 +0200
drm/i915: be more careful when returning -ENXIO in gmbus transfer
Thanks for reporting this bug!