rcar_du_plane_write(rgrp, index, PnDDCR4,
state->format->edf | PnDDCR4_CODE);
+
+ /*
+ * On Gen3, some DU channels have two planes, each being wired to a
+ * separate VSPD instance. The DU can then blend two planes. While
+ * this feature isn't used by the driver, issues related to alpha
+ * blending (such as incorrect colors or planes being invisible) may
+ * still occur if the PnALPHAR register has a stale value. Set the
+ * register to 0 to avoid this.
+ */
+
+ /* TODO: Check if alpha-blending should be disabled in PnMR. */
+ rcar_du_plane_write(rgrp, index, PnALPHAR, 0);
}
static void rcar_du_plane_setup_format(struct rcar_du_group *rgrp,