Ubuntu on an Intel MacBook Pro-how to get trackpad to work?

Pretty much the title. I’ve got an old (circa 2012) MacBook Pro with no screen that’s running Ubuntu, but since day one of the install it has never recognized the touchpad. I’ve been using it with an external mouse, which works, but it’s much less convenient and elegant than if I had even basic touchpad use.

Any ideas on how I might make this work?