Using the correct bit helps. The documentation specifies bit 0 in both registers to be controlling polarity of dpi_vsync_input and dpi_hsync_input polarity. Bit 1 is reserved, and should therefore not be set. Tested with panel that requires active high vsync and hsync. Signed-off-by: Esben Haabendal <esben@xxxxxxxxxx> --- drivers/gpu/drm/bridge/nwl-dsi.c | 8 ++++---- drivers/gpu/drm/bridge/nwl-dsi.h | 4 ++-- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/bridge/nwl-dsi.c b/drivers/gpu/drm/bridge/nwl-dsi.c index 8d54091ec66e..5f05647a3bea 100644 --- a/drivers/gpu/drm/bridge/nwl-dsi.c +++ b/drivers/gpu/drm/bridge/nwl-dsi.c @@ -289,13 +289,13 @@ static int nwl_dsi_config_dpi(struct nwl_dsi *dsi) nwl_dsi_write(dsi, NWL_DSI_INTERFACE_COLOR_CODING, NWL_DSI_DPI_24_BIT); nwl_dsi_write(dsi, NWL_DSI_PIXEL_FORMAT, color_format); - /* - * Adjusting input polarity based on the video mode results in - * a black screen so always pick active low: - */ nwl_dsi_write(dsi, NWL_DSI_VSYNC_POLARITY, + dsi->mode.flags & DRM_MODE_FLAG_PVSYNC ? + NWL_DSI_VSYNC_POLARITY_ACTIVE_HIGH : NWL_DSI_VSYNC_POLARITY_ACTIVE_LOW); nwl_dsi_write(dsi, NWL_DSI_HSYNC_POLARITY, + dsi->mode.flags & DRM_MODE_FLAG_PHSYNC ? + NWL_DSI_HSYNC_POLARITY_ACTIVE_HIGH : NWL_DSI_HSYNC_POLARITY_ACTIVE_LOW); burst_mode = (dsi->dsi_mode_flags & MIPI_DSI_MODE_VIDEO_BURST) && diff --git a/drivers/gpu/drm/bridge/nwl-dsi.h b/drivers/gpu/drm/bridge/nwl-dsi.h index a247a8a11c7c..61e7d65cb1eb 100644 --- a/drivers/gpu/drm/bridge/nwl-dsi.h +++ b/drivers/gpu/drm/bridge/nwl-dsi.h @@ -30,11 +30,11 @@ #define NWL_DSI_PIXEL_FORMAT 0x20c #define NWL_DSI_VSYNC_POLARITY 0x210 #define NWL_DSI_VSYNC_POLARITY_ACTIVE_LOW 0 -#define NWL_DSI_VSYNC_POLARITY_ACTIVE_HIGH BIT(1) +#define NWL_DSI_VSYNC_POLARITY_ACTIVE_HIGH BIT(0) #define NWL_DSI_HSYNC_POLARITY 0x214 #define NWL_DSI_HSYNC_POLARITY_ACTIVE_LOW 0 -#define NWL_DSI_HSYNC_POLARITY_ACTIVE_HIGH BIT(1) +#define NWL_DSI_HSYNC_POLARITY_ACTIVE_HIGH BIT(0) #define NWL_DSI_VIDEO_MODE 0x218 #define NWL_DSI_HFP 0x21c --- base-commit: 7c626ce4bae1ac14f60076d00eafe71af30450ba change-id: 20240814-nwl-dsi-sync-polarity-ddc58435a4c4 Best regards, -- Esben Haabendal <esben@xxxxxxxxxx>