From d5116fb29dc09bd4b9d9175f4f571e6eac539c93 Mon Sep 17 00:00:00 2001 From: Liu Ying Date: Mon, 21 Aug 2023 11:40:02 +0800 Subject: [PATCH] drm/bridge: synopsys: dw-mipi-dsi: Force input bus flags The DATAEN_ACTIVE_LOW bit in DSI_DPI_CFG_POL register is set to zero, so set the DRM_BUS_FLAG_DE_HIGH flag in input_bus_cfg.flags. It appears that the DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE flag also makes sense, so set it in input_bus_cfg.flags too. With this patch, the flags set by drm_atomic_bridge_propagate_bus_flags() are overridden (see comment in that function) in case any downstream bridges propagates invalid flags to this bridge. A real problematic case is to connect a RM67191 MIPI DSI panel whose driver sets DRM_BUS_FLAG_DE_LOW and DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE bus flags. Signed-off-by: Liu Ying Reviewed-by: Robert Foss Signed-off-by: Robert Foss Link: https://patchwork.freedesktop.org/patch/msgid/20230821034008.3876938-4-victor.liu@nxp.com --- drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c index fbd0ae58a951..4e5171b5978a 100644 --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #include #include @@ -567,6 +568,17 @@ dw_mipi_dsi_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge, return input_fmts; } +static int dw_mipi_dsi_bridge_atomic_check(struct drm_bridge *bridge, + struct drm_bridge_state *bridge_state, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state) +{ + bridge_state->input_bus_cfg.flags = + DRM_BUS_FLAG_DE_HIGH | DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE; + + return 0; +} + static void dw_mipi_dsi_video_mode_config(struct dw_mipi_dsi *dsi) { u32 val; @@ -1036,6 +1048,7 @@ static const struct drm_bridge_funcs dw_mipi_dsi_bridge_funcs = { .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state, .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state, .atomic_get_input_bus_fmts = dw_mipi_dsi_bridge_atomic_get_input_bus_fmts, + .atomic_check = dw_mipi_dsi_bridge_atomic_check, .atomic_reset = drm_atomic_helper_bridge_reset, .atomic_pre_enable = dw_mipi_dsi_bridge_atomic_pre_enable, .atomic_enable = dw_mipi_dsi_bridge_atomic_enable,