List of iMac's that will do Target Display Mode

[zl3ag]

These currently work with smc_util ...
27"
A1312 EMC2309 (late 2009)
A1312 EMC2374 (late 2009)
A1312 EMC2390 (mid 2010)

24"
Possibly some of the early 2009 24" iMacs also work but I don't have any to try.

Apple support says the 2011, 2012, 2013, and mid 2014 iMac's also do TDM , but MVHR and MVMR do not appear in the SMC dump. They run Thunderbolt rather than displayport.

If someone has one of those they can do some SMC dumps on in OSX (has to be running OSX High Sierra or earlier) to see what changes when TDM is invoked...

Also, I'm running 2 iMac 27's as external monitors for a Debian 11 Xeon desktop. One running Debian 11, the other running OSX 10.6.8 (Snow Leopard - the last decent version of OSX). The iMac running OSX also appears as an audio sink in Debian. I wonder what would need to be done for the same to happen on the iMac running Linux?

I also use USBIP so I can access the USB ports on the Debian iMac from the Desktop box.

[kgarrels]

see my comment here:
#8 (comment)

[philip-johnson45]

I have an iMac late 2012 running High Sierra alongside an Arch base distro.
I don't use MacOS at all but I want TDM work under linux.
I'm glad I can help. But don't know what to do. I don't know these terminal stuff on MacOS.
If someone gives me some instructions to what to do on mac, I will share the output to fix TDM on Linux on these machines.

[rainerliebe]

I have also an imac 2012,2 running Ubuntu 20/04. It would be great, if someone give me a hint to get it work :)