drm: bridge: ti-sn65dsi83: Fix DSI mode flags for stable …DS output - #1823
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riteshk-quic merged 1 commit intoSep 18, 2026
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…DS output The current DSI mode configuration enables VIDEO_BURST and disables horizontal front porch (HFP) and back porch (HBP) transmission using MIPI_DSI_MODE_VIDEO_NO_HFP and MIPI_DSI_MODE_VIDEO_NO_HBP. However, the SN65DSI83/84 bridge relies on receiving full horizontal timing information over DSI in order to correctly reconstruct the LVDS output timings. When HFP and HBP are not transmitted, the bridge cannot recreate the required timing parameters, resulting in unstable or missing display output on some panels. Additionally, while burst mode is supported by the hardware, its use depends on continuous clock behavior from the DSI host. In practice, burst mode may introduce instability depending on the host controller implementation, as the DSI link may transition to low-power state between bursts. In testing, removing burst mode and ensuring full horizontal timing transmission results in stable LVDS output across affected panels. Update the DSI mode flags to: - Drop MIPI_DSI_MODE_VIDEO_BURST - Drop MIPI_DSI_MODE_VIDEO_NO_HFP - Drop MIPI_DSI_MODE_VIDEO_NO_HBP This aligns with common system configurations where non-burst mode is preferred and full timing information is transmitted over DSI. Link: https://lore.kernel.org/all/20260412053811.662461-2-tessolveupstream@gmail.com/ Signed-off-by: Sudarshan Shetty <tessolveupstream@gmail.com> Signed-off-by: Anand Tiwari <anand.tiwari@oss.qualcomm.com>
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Sep 18, 2026
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The current DSI mode configuration enables VIDEO_BURST and disables horizontal front porch (HFP) and back porch (HBP) transmission using MIPI_DSI_MODE_VIDEO_NO_HFP and MIPI_DSI_MODE_VIDEO_NO_HBP.
However, the SN65DSI83/84 bridge relies on receiving full horizontal timing information over DSI in order to correctly reconstruct the LVDS output timings. When HFP and HBP are not transmitted, the bridge cannot recreate the required timing parameters, resulting in unstable or missing display output on some panels.
Additionally, while burst mode is supported by the hardware, its use depends on continuous clock behavior from the DSI host. In practice, burst mode may introduce instability depending on the host controller implementation, as the DSI link may transition to low-power state between bursts.
In testing, removing burst mode and ensuring full horizontal timing transmission results in stable LVDS output across affected panels.
Update the DSI mode flags to:
This aligns with common system configurations where non-burst mode is preferred and full timing information is transmitted over DSI.
Link: https://lore.kernel.org/all/20260412053811.662461-2-tessolveupstream@gmail.com/
CRs-Fixed: 4673615