How to upload Chef cookbook from current directory?

I'm moving to a workflow of single git repository per chef cookbook. And I have a fairly recent chefdk. I'd like to be able to upload to chef from within the current git repo without a chef-repo behind it. I'm struggling to see how to do that with knife upload. Any ideas. (I can't move to PolicyFiles yet, but I'd like to setup a piece of the workflow now). Any ideas to just "knife upload" from within a git repo easily, would be helful.