Use the same PCLK divide option (divide DSI clock to generate pixel clock)
which is set to LVDS Configuration Register (LVCFG) also for a VSync delay
calculation. Without this change an auxiliary variable could underflow
during the calculation for some dual-link LVDS panels and then calculated
VSync delay is wrong. This leads to a shifted picture on a panel.

Tested-by: Jiri Vanek <jirivan...@gmail.com>
Signed-off-by: Jiri Vanek <jirivan...@gmail.com>
---
 drivers/gpu/drm/bridge/tc358775.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/tc358775.c 
b/drivers/gpu/drm/bridge/tc358775.c
index cd2721ab02a9..fecb8558b49a 100644
--- a/drivers/gpu/drm/bridge/tc358775.c
+++ b/drivers/gpu/drm/bridge/tc358775.c
@@ -430,7 +430,7 @@ static void tc_bridge_enable(struct drm_bridge *bridge)
                val = TC358775_VPCTRL_MSF(1);
 
        dsiclk = mode->crtc_clock * 3 * tc->bpc / tc->num_dsi_lanes / 1000;
-       clkdiv = dsiclk / DIVIDE_BY_3 * tc->lvds_link;
+       clkdiv = dsiclk / (tc->lvds_link == DUAL_LINK ? DIVIDE_BY_6 : 
DIVIDE_BY_3);
        byteclk = dsiclk / 4;
        t1 = hactive * (tc->bpc * 3 / 8) / tc->num_dsi_lanes;
        t2 = ((100000 / clkdiv)) * (hactive + hback_porch + hsync_len + 
hfront_porch) / 1000;
-- 
2.30.2

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