EDID hack

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Tomi Valkeinen

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Feb 5, 2009, 7:20:42 AM2/5/09
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Hi,

I hacked this together just out of interest. The patch is ugly as hell,
and this can't really be done like I do it here =).

With this patch beagle fetches the EDID information from the monitor,
tries to find highest resolution mode that omap can output, tweaking the
timings a bit to make them compatible with omap, and uses that for DVI
output.

Interestingly, even if EDID says that we need inverted syncs, the image
on my IBM monitor becomes scrambled if I invert the sync signals...

Tomi

0001-HACK-DSS2-Hack-for-EDID-testing.patch

chr...@goop.org

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Feb 5, 2009, 1:56:28 PM2/5/09
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Hi Tomi,

I haven't tried your patch but it looks very useful. I'd recommend
trying to use the preferred mode (FB_MISC_1ST_DETAIL) by default as
this is typically the native resolution of the panel. The NVIDIA
proprietary drivers (for example) will hardware scale the user
selected mode to the preferred mode by default.

I'm not surprised about your syncs - DVI EDIDs are often wrong,
incomplete, contradictory, or describe analogue modes which don't work
over the digital interface.

Christopher.
>  0001-HACK-DSS2-Hack-for-EDID-testing.patch
> 5KViewDownload

Frans Meulenbroeks

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Feb 8, 2009, 4:45:10 AM2/8/09
to Beagle Board
>  0001-HACK-DSS2-Hack-for-EDID-testing.patch
> 5KWeergevenDownloaden

Does your patch also result in a working system if the monitor does
not support DDC on the video interface.

FM
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