I've tried connecting my DualSense now for the past couple days, and nothing I do at all will cause it to connect. The MiSTer does not even detect the controller at all (the USB port doesn't have a green light at all when I try to plug in a DualSense) and no inputs do anything.
I've tested multiple other (non-DualSense) controllers in every USB port of the MiSTer and they all work totally fine as expected, with the green light on and inputs functioning normally. Also all my DualSense controllers and cables work totally fine on PC/Steam as well as PS5, just not on the MiSTer.
What I've tried (none of which worked):
a half dozen different DualSenses, including older models and newer models, and even a brand new DualSense fresh from the box
updating my DualSense to latest firmware using PS5
Updating my MiSTer using update_all script
Disabling/enabling fast polling in MiSTer settings
double checked ini settings for anything that could have any impact on a DualSense connecting (couldn't find anything)
Disabling bluetooth on my PS5 and also powered off and unplugged my PS5
a half dozen different USB-C cables of different brands
every single USB port on the MiSTer multiple times
rechecking all my connections, power connections, moving the cable around to make sure it's connected properly
Note that I have not tested Bluetooth, nor do I have any plans to since don't plan on using the controller with BT, and would like to it wired only.
I'm really at a loss as to what could be causing this, and it seems like I'm like the only person on earth having this issue; I did find one other person on reddit with a similar issue, but he never solved it wired, could only use bluetooth.