On Tue, 2022-08-30 at 13:08 +0300, Krzysztof Kozlowski wrote: > On 29/08/2022 05:37, Chunfeng Yun wrote: > > On Fri, 2022-08-26 at 09:36 +0300, Krzysztof Kozlowski wrote: > > > On 26/08/2022 08:36, Chunfeng Yun wrote: > > > > On Tue, 2022-08-23 at 13:24 +0300, Krzysztof Kozlowski wrote: > > > > > On 22/08/2022 10:07, Chunfeng Yun wrote: > > > > > > On Fri, 2022-08-19 at 15:15 +0300, Krzysztof Kozlowski > > > > > > wrote: > > > > > > > On 19/08/2022 12:13, Chunfeng Yun wrote: > > > > > > > > Add a property to set usb2 phy's pre-emphasis. > > > > > > > > > > > > > > > > Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx> > > > > > > > > --- > > > > > > > > Documentation/devicetree/bindings/phy/mediatek,tphy.ya > > > > > > > > ml | > > > > > > > > 7 > > > > > > > > +++++++ > > > > > > > > 1 file changed, 7 insertions(+) > > > > > > > > > > > > > > > > diff --git > > > > > > > > a/Documentation/devicetree/bindings/phy/mediatek,tphy.y > > > > > > > > aml > > > > > > > > b/Documentation/devicetree/bindings/phy/mediatek,tphy.y > > > > > > > > aml > > > > > > > > index 848edfb1f677..aee2f3027371 100644 > > > > > > > > --- > > > > > > > > a/Documentation/devicetree/bindings/phy/mediatek,tphy.y > > > > > > > > aml > > > > > > > > +++ > > > > > > > > b/Documentation/devicetree/bindings/phy/mediatek,tphy.y > > > > > > > > aml > > > > > > > > @@ -219,6 +219,13 @@ patternProperties: > > > > > > > > minimum: 1 > > > > > > > > maximum: 15 > > > > > > > > > > > > > > > > + mediatek,pre-emphasis: > > > > > > > > + description: > > > > > > > > + The selection of pre-emphasis (U2 phy) > > > > > > > > + $ref: /schemas/types.yaml#/definitions/uint32 > > > > > > > > + minimum: 1 > > > > > > > > + maximum: 3 > > > > > > > > > > > > > > Instead of hard-coding register values in bindings, you > > > > > > > should > > > > > > > rather > > > > > > > describe here feature/effect. If it is in units, use unit > > > > > > > suffixes. > > > > > > > If > > > > > > > it is some choice, usually string enum is appropriate. > > > > > > > > > > > > How about changing description as bellow: > > > > > > > > > > > > "The level of pre-emphasis, increases one level, boosts the > > > > > > relative > > > > > > amplitudes of signal's higher frequencies components about > > > > > > 4.16% > > > > > > (U2 > > > > > > phy)" > > > > > > > > > > > > > > > > Still the question is what is the unit. 4.16%? > > > > > > > > No unit, it's a level value, like an index of array. > > > > > > > > > > So a value from register/device programming? > > > > Yes > > > Rather a regular units > > > should be used if that's possible. If not, this should be clearly > > > described here, not some magical number which you encode into > > > DTS... > > > > Ok, I'll add more descriptions. > > Better use logical value, e.g. > https://urldefense.com/v3/__https://github.com/devicetree-org/dt-schema/blob/main/dtschema/schemas/property-units.yaml*L38__;Iw!!CTRNKA9wMg0ARbw!1e-h0R_uwcaHKfKC9qYfaRWYeuWRq1sLCGy3yupNmkFyuW5s1nmRotL7Y0vFG9ETLLTA$ > Optional unit may be -percent or -bp, but the value 4.16% * X (X=1,2,3...)is not an exact value, they are variable in a range and dependent more factors. So I think use level value is simple enough. > > Best regards, > Krzysztof
