Originally Posted by EarlyMon
If the phone uses a simple sd card setup, it'll mount that as USB.
If it uses a portion of storage marked as an internal sd card, you'll need MTP for that.
MTP is a Windows protocol.
If you don't mind wifi, install SwiFTP for full access or any number of wifi-private-web (read: only on your network) solutions. AirDroid is a very good one.
I use MTP, SwiFTP, AirDroid (all free) and like MTP least of all, but your mileage may vary.
I'm not sure what a "simple sd card setup" is. Could you elaborate?
No wifi here in my neck of the woods here in rural India.
mikedt says MTP is supported by Ubuntu, so looks like I'm all set there.