[PATCH] drm/rcar-du: dsi: Handle both DRM_MODE_FLAG_N.SYNC and !DRM_MODE_FLAG_P.SYNC

[Marek Vasut]

Since commit 94fe479fae96 ("drm/rcar-du: dsi: Clean up handling of DRM mode flags")
the driver does not set TXVMVPRMSET0R_VSPOL_LOW and TXVMVPRMSET0R_HSPOL_LOW
for modes which set neither DRM_MODE_FLAG_[PN].SYNC. The previous behavior
was to assume that neither flag means DRM_MODE_FLAG_N.SYNC . Restore the
previous behavior for maximum compatibility.

Fixes: 94fe479fae96 ("drm/rcar-du: dsi: Clean up handling of DRM mode flags")
Signed-off-by: Marek Vasut <marek.vasut+renesas@xxxxxxxxxxx>
---
Cc: David Airlie <airlied@xxxxxxxxx>
Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Cc: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
Cc: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
Cc: Magnus Damm <magnus.damm@xxxxxxxxx>
Cc: Maxime Ripard <mripard@xxxxxxxxxx>
Cc: Simona Vetter <simona@xxxxxxxx>
Cc: Thomas Zimmermann <tzimmermann@xxxxxxx>
Cc: Tomi Valkeinen <tomi.valkeinen+renesas@xxxxxxxxxxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-renesas-soc@xxxxxxxxxxxxxxx
---
 drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c b/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c
index 9413b76d0bfce..98bd7f40adbea 100644
--- a/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c
+++ b/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c
@@ -492,9 +492,11 @@ static void rcar_mipi_dsi_set_display_timing(struct rcar_mipi_dsi *dsi,
 
 	/* Configuration for Video Parameters, input is always RGB888 */
 	vprmset0r = TXVMVPRMSET0R_BPP_24;
-	if (mode->flags & DRM_MODE_FLAG_NVSYNC)
+	if ((mode->flags & DRM_MODE_FLAG_NVSYNC) ||
+	    !(mode->flags & DRM_MODE_FLAG_PVSYNC))
 		vprmset0r |= TXVMVPRMSET0R_VSPOL_LOW;
-	if (mode->flags & DRM_MODE_FLAG_NHSYNC)
+	if ((mode->flags & DRM_MODE_FLAG_NHSYNC) ||
+	    !(mode->flags & DRM_MODE_FLAG_PHSYNC))
 		vprmset0r |= TXVMVPRMSET0R_HSPOL_LOW;
 
 	vprmset1r = TXVMVPRMSET1R_VACTIVE(mode->vdisplay)
-- 
2.51.0