In many applications that require physical interaction with humans or other physical environments, passivity is a useful property to have in order to improve safety and ease of use. Many hydraulic applications (e.g. a human operated excavator) fall into this category. In a previous work, the passivity property of a directional hydraulic flow control valve, and methods for passifying the valve were proposed. In this paper, the problem of developing passifying control laws for directional control valves is re-visited from a bond graph perspective. Two new bond graph elements with power scaling properties are first introduced and the passivity property of bondgraphs containing these elements are investigated. Then by representing the control valve in a suitable augmented bond graph, and by replacing the signal bonds and modulated power sources with power scaling elements, it is shown that passifying control laws can easily be recovered and generalized.