Re: [PATCH 7/9] dt-bindings: spi: mtk-snfi: add two timing delay property

[Xiangsheng Hou (侯祥胜)]

Hi Krzysztof,

On Tue, 2022-11-29 at 08:47 +0100, Krzysztof Kozlowski wrote:
> 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?

Even for specific SoC, the unit of sample delay may be various with
different corner IC.
Besides, whether it`s acceptable by change the property rx-sample-delay 
and rx-latch-latency to mediatek,rx-sample-delay and mediatek,rx-latch-
latency?

Thanks
Xiangsheng Hou