[PATCH 2/3] drm: rcar-du: Only initialise TVM_TVSYNC mode when supported

[Kieran Bingham]

From: Kieran Bingham <kieran.bingham+renesas at ideasonboard.com>

The R-Car DU as found on the D3, E3, and V3U do not have support
for an external synchronisation method.

In these cases, the dsysr cached register should not be initialised
in DSYSR_TVM_TVSYNC, but instead should be left clear to configure as
DSYSR_TVM_MASTER by default.

Signed-off-by: Kieran Bingham <kieran.bingham+renesas at ideasonboard.com>
---
 drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
index ea7e39d03545..cff0d82b9491 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
@@ -1243,7 +1243,10 @@ int rcar_du_crtc_create(struct rcar_du_group *rgrp, unsigned int swindex,
 	rcrtc->group = rgrp;
 	rcrtc->mmio_offset = mmio_offsets[hwindex];
 	rcrtc->index = hwindex;
-	rcrtc->dsysr = (rcrtc->index % 2 ? 0 : DSYSR_DRES) | DSYSR_TVM_TVSYNC;
+	rcrtc->dsysr = (rcrtc->index % 2 ? 0 : DSYSR_DRES);
+
+	if (rcar_du_has(rcdu, RCAR_DU_FEATURE_TVM_SYNC))
+		rcrtc->dsysr |= DSYSR_TVM_TVSYNC;
 
 	if (rcar_du_has(rcdu, RCAR_DU_FEATURE_VSP1_SOURCE))
 		primary = &rcrtc->vsp->planes[rcrtc->vsp_pipe].plane;
-- 
2.30.2