"Driving pressure" usually refers to the set inspiratory pressure for a mandatory breath during pressure control. Pressure support is used to reduce WOB ( increased R due to circuit, ETT, ect.) during spontaneous breaths, Pressure support can be used in volume control as well as pressure control. "Driving pressure" is usually pressure added to PEEP, so you may think of it as "ventilatory pressure". Be wary however (notice I use the term usually!) different people/places/vents use different terminology, correctly or otherwise!