On 29/11/2022 03:50, Xiangsheng Hou (侯祥胜) wrote: >>> --- a/Documentation/devicetree/bindings/spi/mediatek,spi-mtk- >>> snfi.yaml >>> +++ b/Documentation/devicetree/bindings/spi/mediatek,spi-mtk- >>> snfi.yaml >>> @@ -55,6 +55,22 @@ properties: >>> description: device-tree node of the accompanying ECC engine. >>> $ref: /schemas/types.yaml#/definitions/phandle >>> >>> + rx-sample-delay: >> >> No, use existing property, don't invent your own stuff - missing unit >> suffix. See spi-peripheral-props.yaml. > Will change to other private property. The read sample delay with > MediaTek SPI NAND controller can be set with values from 0 to 47. > However, it`s difficult to say the unit of each vaule, because the unit > value will be difference with different chip process or different > corner IC. Why you cannot use same formula as other SPI drivers for sample-delay? And divide/multiple by some factor specific to SoC, which is taken from driver_data? > >>> + description: Rx delay to sample data with this value, the >>> valid >>> + values are from 0 to 47. The delay is smaller >>> than >>> + the rx-latch-latency. >>> + $ref: /schemas/types.yaml#/definitions/uint32 >> >> Drop $ref. > Will do. > >> >>> + minItems: 0 >>> + maxItems: 47 >>> + default: 0 >>> + >>> + rx-latch-latency: >> >> Same problems. Did you check spi-peripheral-props.yaml or other SPI >> controller schemas for such property? >> >>> + description: Rx delay to sample data with this value, the >>> value >>> + unit is clock cycle. >> >> I think the unit should be rather time (e.g. us). >> > Yes, I checked the spi-peripheral-props.yaml and the delay values are > described exactly unit with ns or us. However the unit of MediaTek read > latch latency is clock cycle and it`s difference with different clock > frequency. This is fine in such case. > >>> + $ref: /schemas/types.yaml#/definitions/uint32 >>> + enum: [0, 1, 2, 3] >>> + default: 0 >>> + Best regards, Krzysztof
