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Chunfeng Yungregkh
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dt-bindings: usb: mtk-xhci: add a property for Gen1 isoc-in transfer issue
For Gen1 isoc-in endpoint on controller before about SSUSB IPM v1.6.0, it still send out unexpected ACK after receiving a short packet in burst transfer, this will cause an exception on connected device, specially for a 4k camera. Add a quirk property "rx-fifo-depth" to work around this hardware issue, prefer to use 3k bytes; The side-effect is that it may cause performance drop about 10%, including bulk transfer. Acked-by: Krzysztof Kozlowski <[email protected]> Reviewed-by: AngeloGioacchino Del Regno <[email protected]> Signed-off-by: Chunfeng Yun <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
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Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml

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@@ -124,6 +124,17 @@ properties:
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defined in the xHCI spec on MTK's controller.
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default: 5000
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rx-fifo-depth:
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$ref: /schemas/types.yaml#/definitions/uint32
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description:
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It is a quirk used to work around Gen1 isoc-in endpoint transfer issue
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that still send out unexpected ACK after device finishes the burst
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transfer with a short packet and cause an exception, specially on a 4K
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camera device, it happens on controller before about IPM v1.6.0;
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the side-effect is that it may cause performance drop about 10%,
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including bulk transfer, prefer to use 3k here. The size is in bytes.
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enum: [1024, 2048, 3072, 4096]
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# the following properties are only used for case 1
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wakeup-source:
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description: enable USB remote wakeup, see power/wakeup-source.txt

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