The Helitron DV4mini dongle has been used at my QTH running with a windows tablet as a hotspot for both DMR+ and D-Star.
A spare Raspberry Pi2 has now been used with the Linux(ARM) version of the DV4mini software, downloaded from here. There are instructions for downloading and configuring a customised Raspian image for the Raspberry Pi2 which can be obtained here. Note that a 8GB or larger microSD card is recommended.
Help has been provided with a Youtube video by Pascal VA2PV of Laboenligne.ca – this shows how software and firmware updates can be applied. There are other related videos for the DV4mini available on Youtube.
Once setup, The Raspberry Pi2 autostarts on switch on and can be controlled via VNC from your PC.
The DV4mini acts as a hotspot also for D-Star and Yaesu (Fusion) C4FM. The photos below show it set up for DMR+ at my QTH.
[06Dec2015 edited by John G8DZH]