Quoting Ville Syrjälä (2020-10-29 14:07:46)
On Thu, Oct 29, 2020 at 11:00:30AM +0000, Chris Wilson wrote:
We have a few displays in CI that always report their EDID as a bunch of zeroes. This is consistent behavioud, so one assumes intentional indication of an "absent" EDID. Let us treat is as such by silently reporting the zero edid using connector->null_edid_counter, leaving the loud carp to EDID that violate their checksums or otherwise return unexpected illegal data upon reading. These are more likely to be inconsistent bad connections rather than being intended.
I don't think null_edid_counter is actually used by anything. So apart from wondering why the mode list has turned strange is there some way I can still see from the logs that the EDID has become all zeroes?
The ones in question, it's every time we read the EDID it comes back zero. I am betting that transient everything-is-zero rather than spurious data is rare enough not to worry about.
An alternative would be to pass the log level to the bad_edid dumper, or just make it debug for even gibberish edids? -Chris