FE_OUTPUT0_PAD
.link_pad = FE_OUTPUT0_PAD
struct vb2_buffer *buf = vb2_bufs[FE_OUTPUT0_PAD + i];
fmt = v4l2_subdev_state_get_format(state, FE_OUTPUT0_PAD);
fmt = v4l2_subdev_state_get_format(state, FE_OUTPUT0_PAD);
case FE_OUTPUT0_PAD:
fe->pad[FE_OUTPUT0_PAD].flags = MEDIA_PAD_FL_SOURCE;