From 8431fff9e0f3fc1c5844cf99a73b49b63ceed481 Mon Sep 17 00:00:00 2001 From: Wojciech Macek Date: Wed, 17 Apr 2024 10:38:19 +0000 Subject: [PATCH] drm/mediatek: dp: Fix mtk_dp_aux_transfer return value In case there is no DP device attached to the port the transfer function should return IO error, similar to what other drivers do. In case EAGAIN is returned then any read from /dev/drm_dp_aux device ends up in an infinite loop as the upper layers constantly repeats the transfer request. Fixes: f70ac097a2cf ("drm/mediatek: Add MT8195 Embedded DisplayPort driver") Signed-off-by: Wojciech Macek Reviewed-by: AngeloGioacchino Del Regno Reviewed-by: CK Hu Link: https://patchwork.kernel.org/project/dri-devel/patch/20240417103819.990512-1-wmacek@chromium.org/ Signed-off-by: Chun-Kuang Hu --- drivers/gpu/drm/mediatek/mtk_dp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c index 0ba72102636aa..536366956447a 100644 --- a/drivers/gpu/drm/mediatek/mtk_dp.c +++ b/drivers/gpu/drm/mediatek/mtk_dp.c @@ -2104,7 +2104,7 @@ static ssize_t mtk_dp_aux_transfer(struct drm_dp_aux *mtk_aux, if (mtk_dp->bridge.type != DRM_MODE_CONNECTOR_eDP && !mtk_dp->train_info.cable_plugged_in) { - ret = -EAGAIN; + ret = -EIO; goto err; } -- 2.30.2