Currently, mtk_dsi_lane_ready (which setup the DSI lane) is triggered before mtk_dsi_poweron. lanes_ready flag toggle to true during mtk_dsi_lane_ready function, and the DSI module is set up during mtk_dsi_poweron. Later, during panel driver init, mtk_dsi_lane_ready is triggered but does nothing because lanes are considered ready. Unfortunately, when the panel driver try to communicate, the DSI returns a timeout. The solution found here is to put lanes_ready flag to false after the DSI module setup into mtk_dsi_poweron to init the DSI lanes after the power / setup of the DSI module. Signed-off-by: Alexandre Mergnat <amergnat@xxxxxxxxxxxx> --- drivers/gpu/drm/mediatek/mtk_dsi.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c index 3b7d13028fb6..35c36cc05c04 100644 --- a/drivers/gpu/drm/mediatek/mtk_dsi.c +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c @@ -667,6 +667,8 @@ static int mtk_dsi_poweron(struct mtk_dsi *dsi) mtk_dsi_config_vdo_timing(dsi); mtk_dsi_set_interrupt_enable(dsi); + dsi->lanes_ready = false; + return 0; err_disable_engine_clk: clk_disable_unprepare(dsi->engine_clk); -- b4 0.10.1