If that’s what you are looking for, and you don’t mind paying $5, there is an add-on called Mavis Up Button that does exactly that, and nothing more.
The Up button works in Explorer:
Or in Control Panel:
There’s only one bug… the button stays “active” even if you are “up” as far as you can go (the Desktop). It’s not a big deal, but perfectionists might be annoyed by it.
If you are using a custom visual style, you’ll also notice that it doesn’t change with those themes.
Download Mavis Up Button Trial Version