megi's PinePhone Development Log RSS

2021–10–26: Pinephone HDMI hot-plug-detection HW bug fixed

The HDMI HPD HW bug I discovered previously that breaks USB-C Alt-DP mode was confirmed by the product team.

I've took some time to figure out a software based workaround to signalling hot-plug detection signal (HPD) from ANX7688 HDMI bridge to HDMI PHY inside the SoC and the rest of the DRM driver stack.

If you had issues with Alt-DP stopping at DP state 0x03 and not going further and was not able to use Pinephone with a HDMI dock connected to a monitor, now you should be able to with my 5.15 Linux kernel.