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 <victor.liu@xxxxxxx> --- v1->v3: * No change. 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 945d46a76995..ed9288a9c444 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 <drm/bridge/dw_mipi_dsi.h> #include <drm/drm_atomic_helper.h> #include <drm/drm_bridge.h> +#include <drm/drm_connector.h> #include <drm/drm_crtc.h> #include <drm/drm_mipi_dsi.h> #include <drm/drm_modes.h> @@ -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, -- 2.37.1