Hector Martin

sounds pretty cool for a raspberry or something tbh

Yeah except the Raspberry isn't designed for that and doesn't actually run on 5V through HDMI, but it tries to, and then it won't shut down when you pull the power, nor reboot properly when you power it again, and you have to disconnect HDMI every time.

Maybe because MHL: https://en.wikipedia.org/wiki/Mobile_High-Definition_Link … Because the same five-pin Micro-USB port is also typically used for charging the device, the sink is required to provide power to maintain the state of charge (or even recharge)

[...] The specification introduces a reversible 32-pin superMHL connector, which (along with USB Type-C) supports a higher charging power of up to 40 W (20 V / 2 A), and is designed for future bandwidth expansion.

Pin 18 - +5V Power. http://hdmiconnect.com/downloads/HDMI%20Pinout.pdf …

From *source* to *sink*. Not the other way around.

Dell monitors have a problem with this and DisplayPort. Broke the WiFi card on one of my Macs three times before I figured it out and bought a cable that just didn't have pin 20 connected.

link to cable? I have a Dell P2415Q which has forever had problems resuming from standby, maybe this is the reason. U2718Q doesn't seem to have the problem, fwiw.