Device validation and process validation should be kept separate, make reference to 7.5.6 in the D & D procedure but do not try and encompass it all. I know it all seems a bit chicken and egg " but how can i validate the device if i have not validated the process" but, the aim of device validation is to ensure the DESIGN meets the intended specification/user needs/intended use etc. Once you have a design that works, you can design,verify and validate the process to make it.
I don't generally deal with software, but i would hazard a guess that software embedded in the device falls under 7.3, software used in manufacturing (cnc programs etc) would be in 7.5.6.