[PATCH] drm/radeon: fix regression on atom cards with hardcoded EDID record.

[Alex Deucher]

On Sun, May 1, 2011 at 5:03 PM, Dave Airlie <airlied at gmail.com> wrote:
> On Mon, May 2, 2011 at 4:26 AM, Alex Deucher <alexdeucher at gmail.com> wrote:
>> On Sun, May 1, 2011 at 6:16 AM, Dave Airlie <airlied at gmail.com> wrote:
>>> From: Dave Airlie <airlied at redhat.com>
>>>
>>> Since fafcf94e2b5732d1e13b440291c53115d2b172e9 introduced an edid size, it seems to have broken this path.
>>>
>>> This manifest as oops on T500 Lenovo laptops with dual graphics primarily.
>>>
>>> Should fix: https://bugzilla.kernel.org/show_bug.cgi?id=33812
>>>
>>> Signed-off-by: Dave Airlie <airlied at redhat.com>
>>> cc: stable at kernel.org
>>
>> Reviewed-by: Alex Deucher <alexdeucher at gmail.com>
>>
>> Although, I think there may be a problem with the mux switching since
>> we shouldn't hit the hardcoded EDID unless DDC fails.
>
> I've avoided having to do a MUX switch for DDC so far since I've no
> idea how to enumerate what the MUX is attached to properly.

Ah ok.  That would explain the bugs where VGA/DVI ddc doesn't work you
switch gfx.

Alex

>
> The good thing is the table has worked fine up until now.
>
> Dave.
>