[RFC PATCH 1/1] drm/bridge: ti-sn65dsi83: Remove burst mode

[estl at gmx.net]

From: Eberhard Stoll <eberhard.stoll at kontron.de>

Remove LVDS panel overclocking for some configurations by disabling
burst mode for this chip

With burst mode enabled, some DSI controllers increase their DSI lane
clock beyond the clock which is needed to transfer all pixel data.

But this driver operates with a pixel clock derived from the DSI lane
clock by a fixed prescaler. So, every increase of the DSI clock also
increases the LVDS pixel clock. In this case, the LVDS pixel clock is
overclocked.

This is the case e.g. for synopsys stm DSI bridge
(drm/stm/dw_mipi_dsi-stm.c). With burst mode the DSI clock is
increased by 20% and therefore also for the LVDS panel.

Signed-off-by: Eberhard Stoll <eberhard.stoll at kontron.de>
---
 drivers/gpu/drm/bridge/ti-sn65dsi83.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi83.c b/drivers/gpu/drm/bridge/ti-sn65dsi83.c
index c901c0e1a3b0..ffc39208536e 100644
--- a/drivers/gpu/drm/bridge/ti-sn65dsi83.c
+++ b/drivers/gpu/drm/bridge/ti-sn65dsi83.c
@@ -272,7 +272,7 @@ static int sn65dsi83_attach(struct drm_bridge *bridge,

 	dsi->lanes = ctx->dsi_lanes;
 	dsi->format = MIPI_DSI_FMT_RGB888;
-	dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST;
+	dsi->mode_flags = MIPI_DSI_MODE_VIDEO;

 	ret = mipi_dsi_attach(dsi);
 	if (ret < 0) {
--
2.25.1