On 3/5/25 11:10, Hans Verkuil wrote: > On 05/03/2025 01:59, Tim Surber wrote: >> Hi Dmitry, >> >> I did some more testing. That the Apple TV did not work was a bit >> misleading. >> >> It was just, that the Apple TV defaulted to 4:4:4 Chroma which does not >> work at all for me. (The same happens using the vendor driver). >> >> When I changed the EDID to match the vendor driver the HDMI handshake >> happened with 4:2:0 chroma, where I could verify even 4k60fps using your >> driver, nice! >> >> So the remaining problems I see are: >> - 4:4:4 chroma not working in any resolution >> - 4:2:2 and RGB not working in 4k60fps (is this a hardware limitation?) >> >> A possible workaround could be to disable these non supported formats in >> the default EDID. > I would like to merge this driver this week, since otherwise it will likely > slip to v6.16. So if there is a working EDID, perhaps it can be used for now, > and later on it can be patched if there is a better EDID. > > Would this EDID work? Tim, can you try this? > > v4l2-ctl --set-edid type=hdmi-4k-600mhz,ycbcr444,ycbcr422 > > Alternatively, if there is indeed a HW limitation that prevents 4kp60 to work, > try this: > > v4l2-ctl --set-edid type=hdmi-4k-300mhz,ycbcr444,ycbcr422 > > Whichever of the two works is what we can use as default EDID. Disabling 444 and 422 is an option. Though, they work on my setup at 4k@60p. In general, it often a challenge to get 4k@60p properly with any of these small board devices. 4k@60p works only using a short HDMI cable for me. Also, not everyone aware that the micro HDMI adapter needs to be compliant with HDMI 2.0 for 4k@60, that's why 300MHz is the default. Will be nice to have the good EDID enabled by default in the defconfig. Dealing with problems like that will be a headache for majority of people, IMO. -- Best regards, Dmitry
