From ec1aaf792d9aafbe1d1ffd414c423ddc2a3d3103 Mon Sep 17 00:00:00 2001 From: Axe Yang Date: Thu, 7 Dec 2023 14:35:34 +0800 Subject: [PATCH] dt-bindings: mmc: mtk-sd: add tuning steps related property Add 'mediatek,tuning-steps' setting. This property will give MSDC a chance to extend tuning steps up to 64. With more tuning steps, MSDC may achieve a more optimal calibration result, thus avoiding potential CRC issues. Reviewed-by: Krzysztof Kozlowski Signed-off-by: Axe Yang Reviewed-by: AngeloGioacchino Del Regno Link: https://lore.kernel.org/r/20231207063535.29546-2-axe.yang@mediatek.com Signed-off-by: Ulf Hansson --- Documentation/devicetree/bindings/mmc/mtk-sd.yaml | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/Documentation/devicetree/bindings/mmc/mtk-sd.yaml b/Documentation/devicetree/bindings/mmc/mtk-sd.yaml index 3fffa467e4e1c..c532ec92d2d9c 100644 --- a/Documentation/devicetree/bindings/mmc/mtk-sd.yaml +++ b/Documentation/devicetree/bindings/mmc/mtk-sd.yaml @@ -145,6 +145,15 @@ properties: minimum: 0 maximum: 7 + mediatek,tuning-step: + $ref: /schemas/types.yaml#/definitions/uint32 + description: + Some SoCs need extend tuning step for better delay value to avoid CRC issue. + If not present, default tuning step is 32. For eMMC and SD, this can yield + satisfactory calibration results in most cases. + enum: [32, 64] + default: 32 + resets: maxItems: 1 -- 2.30.2