From: David Jander <da...@protonic.nl>

The documentation is not clear about how this delay works.
Empirical tests have shown that with a VSDELAY of 0, the first
scanline is not properly formatted in the output stream when
DSI->DP mode is used. The calculation spreadsheets from Toshiba
seem to always make this value equal to the HFP + 10 for DSI->DP
use-case. For DSI->DPI this value should be > 2 and for DPI->DP
it seems to always be 0x64.

Signed-off-by: David Jander <da...@protonic.nl>
Signed-off-by: Lucas Stach <l.st...@pengutronix.de>
---
 drivers/gpu/drm/bridge/tc358767.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/tc358767.c 
b/drivers/gpu/drm/bridge/tc358767.c
index 46916ae30f8f..9f2c67b4a488 100644
--- a/drivers/gpu/drm/bridge/tc358767.c
+++ b/drivers/gpu/drm/bridge/tc358767.c
@@ -817,7 +817,7 @@ static int tc_set_common_video_mode(struct tc_data *tc,
         * sync signals
         */
        ret = regmap_write(tc->regmap, VPCTRL0,
-                          FIELD_PREP(VSDELAY, 0) |
+                          FIELD_PREP(VSDELAY, right_margin + 10) |
                           OPXLFMT_RGB888 | FRMSYNC_DISABLED | MSF_DISABLED);
        if (ret)
                return ret;
-- 
2.39.2

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