pvr2_ctrl_get_max
int pvr2_ctrl_get_max(struct pvr2_ctrl *);
val = pvr2_ctrl_get_max(cip->cptr);
lmax = pvr2_ctrl_get_max(hcp);
lmax = pvr2_ctrl_get_max(vcp);
vc->maximum = pvr2_ctrl_get_max(cptr);