On 10/14/2012 02:19 PM, Bruno Prémont wrote:
> On Sun, 14 October 2012 Mark Hounschell <dmarkh@cfl.rr.com> wrote:
>>>> And could I ask if this simple pgm might work to build the file I need?
>>>
>>> It looks fine. You can also check the output with hexdump just to
>>> make sure it looks sane.
>>
>> Did that and the data looks swapped compared to the array written, but I
>> guess that's normal?
>
> That might very well be presentation issue, how did you call hexdump?
> When called with no arguments but filename it groups bytes as words and
> those look swapped (on little-endian), but `hexdump -C $file` is fine,
> dumping each byte individually.
>

Yep, its right with -C

>>> If it's broken kernel will tell you that checksum does not match.
>>>
>>
>> So the  check sum is actually already in the data provided by the service
>> manual then.
>
> Yes, checksum byte is part of the EDID blob.
>
> Bruno
>
>>> In any case the (successful) loading of edid should be visible in kernel
>>> log.
>>>
>>
>> I'll be trying this a little later in the day.

I gave it a try. I don't think it liked my kernel cmdline. dmesg attached. 
There is a lot more in there now that nomodeset is gone and the debug is 
turned on.

# ls -al /lib/firmware/edid/lg42lb9df.edid
-rw-r--r-- 1 root root 1024 Oct 14  2012 /lib/firmware/edid/lg42lb9df.edid

## cat /proc/cmdline
root=/dev/disk/by-id/ata-INTEL_SSDSC2CW060A3_CVCV205106EB060AGN-part4 
noresume splash=silent quiet apm=off vga=normal drm.debug=0xe irqpoll 
drm_kms_helper.edid_firmware=edid/lg42lb9df.edid


from attached dmesg:
1.833032] drm_kms_helper: Unknown parameter `edid'

Mark