struct ff_effect — defines force feedback effect
struct ff_effect { __u16 type; __s16 id; __u16 direction; struct ff_trigger trigger; struct ff_replay replay; union u; };
type of the effect (FF_CONSTANT, FF_PERIODIC, FF_RAMP, FF_SPRING, FF_FRICTION, FF_DAMPER, FF_RUMBLE, FF_INERTIA, or FF_CUSTOM)
an unique id assigned to an effect
direction of the effect
trigger conditions (struct ff_trigger)
scheduling of the effect (struct ff_replay)
effect-specific structure (one of ff_constant_effect, ff_ramp_effect, ff_periodic_effect, ff_condition_effect, ff_rumble_effect) further defining effect parameters