ICVS_CSI_PAD_SOURCE
v4l2_subdev_state_get_format(state, ICVS_CSI_PAD_SOURCE);
if (format->pad == ICVS_CSI_PAD_SOURCE) { /* source pad mirrors sink */
ctx->pads[ICVS_CSI_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;