[Intel-gfx] i915: Dell E6410 Ironlake display detection

[Ben Guthro]

FWIW, I filed a bug here on this issue, to have something to attach
the output of various useful info
https://bugs.freedesktop.org/show_bug.cgi?id=28746


On Thu, Jun 24, 2010 at 2:55 PM, Ben Guthro
<ben.guthro+intel-gfx at gmail.com> wrote:
> I posted a similar question to LKML yesterday, but perhaps this is a
> better forum for this discussion, as it seemed to get lost amongst
> many other non-graphics related discussions.
>
> I have a problematic machine, that I have traced the problem down to
> what I think is an issue with the i915 detection of the LVDS on the
> Ironlake chip.
>
> The machine in question is a Dell Latitude E6410 - i5 laptop, with the
> intel Ironlake chip, and the failure condition is such that when the
> boot sequence switches into KMS mode, the screen
> goes black, and never comes back.
>
> It seems to be very similar to both
> https://bugs.freedesktop.org/show_bug.cgi?id=28224
> and
> https://bugs.freedesktop.org/show_bug.cgi?id=28070
>
> However, I have tried all of the patches suggested on these bugs, to
> no avail (yet)
>
> My base install is Ubuntu 10.04, and I've spun through a few kernels
> to try to bisect the problem. Unfortunately, I've been unable to find
> a kernel that works, but I have settled on linus' 2.6.35rc3 for
> debugging this...
>
> I can get the machine to come up on an external display, if switched
> at the BIOS screen...but /sys/class/card0 never shows an LVDS...and
> dmesg doesn't seem to be throwing any errors.
>
> If you have any thoughts on what I might try next, in attempting to
> debug this issue, I'd appreciate any pointers, as the intel cards
> isn't my particular area of expertise, but am capable enough to read
> the code...
>
>
> Regards,
>
> Ben
>