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Check the return value to confirm that AUX communication is successful. Fixes: f70ac097a2cf ("drm/mediatek: Add MT8195 Embedded DisplayPort driver") Signed-off-by: Liankun Yang --- Changes in V4: - Fix IF judgement condition. Per suggestion from the previous thread: https://patchwork.kernel.org/project/linux-mediatek/patch/20241218113448.2992-1-liankun.yang@mediatek.com/ Changes in V3: - Using drm_dp_read_sink_count() to improve patch. Per suggestion from the previous thread: https://patchwork.kernel.org/project/linux-mediatek/patch/20241128030940.25657-1-liankun.yang@mediatek.com/ Changes in V2: - Modify Fixes in Commit Message. Per suggestion from the previous thread: https://patchwork.kernel.org/project/linux-mediatek/patch/20240930092000.5385-1-liankun.yang@mediatek.com/ --- drivers/gpu/drm/mediatek/mtk_dp.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c index 36713c176cfc..b8e4e9a6eb78 100644 --- a/drivers/gpu/drm/mediatek/mtk_dp.c +++ b/drivers/gpu/drm/mediatek/mtk_dp.c @@ -2100,7 +2100,6 @@ static enum drm_connector_status mtk_dp_bdg_detect(struct drm_bridge *bridge) struct mtk_dp *mtk_dp = mtk_dp_from_bridge(bridge); enum drm_connector_status ret = connector_status_disconnected; bool enabled = mtk_dp->enabled; - u8 sink_count = 0; if (!mtk_dp->train_info.cable_plugged_in) return ret; @@ -2115,8 +2114,8 @@ static enum drm_connector_status mtk_dp_bdg_detect(struct drm_bridge *bridge) * function, we just need to check the HPD connection to check * whether we connect to a sink device. */ - drm_dp_dpcd_readb(&mtk_dp->aux, DP_SINK_COUNT, &sink_count); - if (DP_GET_SINK_COUNT(sink_count)) + + if (drm_dp_read_sink_count(&mtk_dp->aux) > 0) ret = connector_status_connected; if (!enabled) -- 2.45.2