Currently working on getting GPIO based I2C bus working for OpenChrome DDX

I am currently working on getting MSI CN700T mainboard’s DVI to properly handle the screen resolutions the monitor actually supports. At the present time, the DVI coming out of this mainboard can display certain screen resolutions X Server provides by default if EDID was not received by the DDX. I do not find this behavior to be very desirable. The issue I am observing here is that VIA Technologies VT1632A DVI transmitter is connected to GPIO2 / 3 pins to emulate I2C bus, but it is not working for the purpose of receiving EDID. That being said, it works for the purpose of detecting and controlling VT1632A. Please note that the code I am talking about is the existing OpenChrome DDX UMS (User Mode Setting) code for the upcoming Version 0.7 release.

Strange twist (?) to this saga is that if I let OpenChrome DRM to perform KMS (Kernel Mode Setting), its GPIO based I2C code works well, and I am able to obtain EDID from the monitor.

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