Nouveau - Feb 2013 - Monitor with corrupted EDID

For an unknown reason both my monitors ended up with a corrupted EDID.
They both provide VGA and DVI input. The VGA input works fine, while
DVI is broken because of the EDID issue.

Using these [1] instructions I have been able to read the EDID and fix
it. Unfortunately I'm not able to write it back to the eeprom.
I always get this message:
  i2c i2c-1: sendbytes: NAK bailout.

This is what I usually see in /var/log/message
[dump of the EDID]
nouveau 0000:01:00.0: DVI-D-1: EDID block 0 invalid.
[drm] nouveau 0000:01:00.0: DDC responded, but no EDID for DVI-D-1

Do you know why writing to the monitor does not work? I suspect the
eeprom is write protected

Googling a bit I noticed the nvidia driver allows to ignore the EDID
returned by the monitor and use a custom one. I looks like the nouveau
drivers do not offer this feature. Am I wrong?

These are my specs:
  * kernel: 3.4.11-2.16-desktop
  * architecture: x86_64
  * distribution: openSUSE 12.2
  * xorg-x11-driver-video-nouveau-0.0.16_20120321_ab7291d-3.5.1.x86_64
  * X.Org X Server 1.12.3
  * NVIDIA Corporation G84M [Quadro FX 570M]
  * Monitor 1: lenovo l220x wide
  * Monitor 2: lenovo l2440p


What should I do?

Thanks in advance
Flavio

On Thu, Feb 07, 2013 at 04:16:54PM +0100, Flavio Castelli
wrote:
> For an unknown reason both my monitors ended up with a corrupted EDID.
> They both provide VGA and DVI input. The VGA input works fine, while
> DVI is broken because of the EDID issue.
> 
> Using these [1] instructions I have been able to read the EDID and fix
> it. Unfortunately I'm not able to write it back to the eeprom.
> I always get this message:
>   i2c i2c-1: sendbytes: NAK bailout.
> 
> This is what I usually see in /var/log/message
> [dump of the EDID]
> nouveau 0000:01:00.0: DVI-D-1: EDID block 0 invalid.
> [drm] nouveau 0000:01:00.0: DDC responded, but no EDID for DVI-D-1
> 
> Do you know why writing to the monitor does not work? I suspect the
> eeprom is write protected
> 
> Googling a bit I noticed the nvidia driver allows to ignore the EDID
> returned by the monitor and use a custom one. I looks like the nouveau
> drivers do not offer this feature. Am I wrong?
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=blob;f=Documentation/EDID/HOWTO.txt
> 
> These are my specs:
>   * kernel: 3.4.11-2.16-desktop
>   * architecture: x86_64
>   * distribution: openSUSE 12.2
>   * xorg-x11-driver-video-nouveau-0.0.16_20120321_ab7291d-3.5.1.x86_64
>   * X.Org X Server 1.12.3
>   * NVIDIA Corporation G84M [Quadro FX 570M]
>   * Monitor 1: lenovo l220x wide
>   * Monitor 2: lenovo l2440p
> 
> 
> What should I do?
> 
> Thanks in advance
> Flavio

On 02/07/2013 10:16 AM, Flavio Castelli wrote:
> For an unknown reason both my monitors ended up with a corrupted EDID.
> They both provide VGA and DVI input. The VGA input works fine, while
> DVI is broken because of the EDID issue.
>
> Using these [1] instructions I have been able to read the EDID and fix
> it. Unfortunately I'm not able to write it back to the eeprom.
> I always get this message:
>    i2c i2c-1: sendbytes: NAK bailout.
>
> This is what I usually see in /var/log/message
> [dump of the EDID]
> nouveau 0000:01:00.0: DVI-D-1: EDID block 0 invalid.
> [drm] nouveau 0000:01:00.0: DDC responded, but no EDID for DVI-D-1
>
> Do you know why writing to the monitor does not work? I suspect the
> eeprom is write protected
>
> Googling a bit I noticed the nvidia driver allows to ignore the EDID
> returned by the monitor and use a custom one. I looks like the nouveau
> drivers do not offer this feature. Am I wrong?
>
> These are my specs:
>    * kernel: 3.4.11-2.16-desktop
>    * architecture: x86_64
>    * distribution: openSUSE 12.2
>    * xorg-x11-driver-video-nouveau-0.0.16_20120321_ab7291d-3.5.1.x86_64
>    * X.Org X Server 1.12.3
>    * NVIDIA Corporation G84M [Quadro FX 570M]
>    * Monitor 1: lenovo l220x wide
>    * Monitor 2: lenovo l2440p
>
>
> What should I do?
>
> Thanks in advance
> Flavio
> _______________________________________________
> Nouveau mailing list
> Nouveau at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/nouveau
>
I recently used a DOS program called ddcw.exe to fix the corrupted EDID 
on one of my monitors.

See this site, http://byuu.org/articles/computing/edid
and get it here, http://www.komeil.com/download/2984

If that doesn't work, the drm_kms_helper module in newer kernels should 
have a parameter to get around the problem.

See https://www.osadl.org/Single-View.111+M50eaf2f2c66.0.html

-Mike