You can now control ToalMix from an Ipad, Mac or pc. It works with all RME devices that support TotalMix so your good to go with your HDSP card. It's downloadable from the RME forum and there's a feature list and manual too:

https://www.forum.rme-audio.de/viewtopic.php?id=26568

Looks really cool but I haven't fooled around with TotalMix yet. Without EQ and FX it probably won't work that well as a standalone mixer. You'll need an RME interface with dedicated dsp chip if you want to use it as standalone : https://www.youtube.com/watch?v=yfhNh4WmPso