drm/bridge: cdns-dsi: Fix event mode

The timings calculation gets it wrong for DSI event mode, resulting in
too large hbp value. Fix the issue by taking into account the
pulse/event mode difference.

Tested-by: Parth Pancholi <parth.pancholi@toradex.com>
Reviewed-by: Jayesh Choudhary <j-choudhary@ti.com>
Tested-by: Jayesh Choudhary <j-choudhary@ti.com>
Reviewed-by: Devarsh Thakkar <devarsht@ti.com>
Link: https://lore.kernel.org/r/20250723-cdns-dsi-impro-v5-13-e61cc06074c2@ideasonboard.com
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>

diff --git a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c
index 07f8d5f5c2aaad4a12424f42afb14f66092e7d9a..3bc4d011b4c6868276a8f55dbfd44560b7ca95e2 100644 (file)
--- a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c
+++ b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c
@@ -418,7 +418,8 @@
 #define DSI_OUTPUT_PORT                        0
 #define DSI_INPUT_PORT(inputid)                (1 + (inputid))
 
-#define DSI_HBP_FRAME_OVERHEAD         12
+#define DSI_HBP_FRAME_PULSE_OVERHEAD   12
+#define DSI_HBP_FRAME_EVENT_OVERHEAD   16
 #define DSI_HSA_FRAME_OVERHEAD         14
 #define DSI_HFP_FRAME_OVERHEAD         6
 #define DSI_HSS_VSS_VSE_FRAME_OVERHEAD 4
@@ -487,23 +488,31 @@ static int cdns_dsi_mode2cfg(struct cdns_dsi *dsi,
 
        bpp = mipi_dsi_pixel_format_to_bpp(output->dev->format);
 
-       dsi_cfg->hbp = dpi_to_dsi_timing(dpi_hbp + (sync_pulse ? 0 : dpi_hsa),
-                                        bpp, DSI_HBP_FRAME_OVERHEAD);
+       if (sync_pulse) {
+               dsi_cfg->hbp = dpi_to_dsi_timing(dpi_hbp, bpp,
+                                                DSI_HBP_FRAME_PULSE_OVERHEAD);
 
-       if (sync_pulse)
-               dsi_cfg->hsa =
-                       dpi_to_dsi_timing(dpi_hsa, bpp, DSI_HSA_FRAME_OVERHEAD);
+               dsi_cfg->hsa = dpi_to_dsi_timing(dpi_hsa, bpp,
+                                                DSI_HSA_FRAME_OVERHEAD);
+       } else {
+               dsi_cfg->hbp = dpi_to_dsi_timing(dpi_hbp + dpi_hsa, bpp,
+                                                DSI_HBP_FRAME_EVENT_OVERHEAD);
+
+               dsi_cfg->hsa = 0;
+       }
 
        dsi_cfg->hact = dpi_to_dsi_timing(dpi_hact, bpp, 0);
 
        dsi_cfg->hfp = dpi_to_dsi_timing(dpi_hfp, bpp, DSI_HFP_FRAME_OVERHEAD);
 
-       dsi_cfg->htotal = dsi_cfg->hbp + DSI_HBP_FRAME_OVERHEAD;
-       if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
-               dsi_cfg->htotal += dsi_cfg->hsa + DSI_HSA_FRAME_OVERHEAD;
+       dsi_cfg->htotal = dsi_cfg->hact + dsi_cfg->hfp + DSI_HFP_FRAME_OVERHEAD;
 
-       dsi_cfg->htotal += dsi_cfg->hact;
-       dsi_cfg->htotal += dsi_cfg->hfp + DSI_HFP_FRAME_OVERHEAD;
+       if (sync_pulse) {
+               dsi_cfg->htotal += dsi_cfg->hbp + DSI_HBP_FRAME_PULSE_OVERHEAD;
+               dsi_cfg->htotal += dsi_cfg->hsa + DSI_HSA_FRAME_OVERHEAD;
+       } else {
+               dsi_cfg->htotal += dsi_cfg->hbp + DSI_HBP_FRAME_EVENT_OVERHEAD;
+       }
 
        return 0;
 }