Re: [PATCH 2/7] dt-bindings: phy: mediatek,tphy: add property to set pre-emphasis
From: Krzysztof Kozlowski <hidden>
Date: 2022-08-26 06:37:05
Also in:
linux-devicetree, linux-mediatek, linux-phy, lkml
On 26/08/2022 08:36, Chunfeng Yun wrote:
On Tue, 2022-08-23 at 13:24 +0300, Krzysztof Kozlowski wrote:quoted
On 22/08/2022 10:07, Chunfeng Yun wrote:quoted
On Fri, 2022-08-19 at 15:15 +0300, Krzysztof Kozlowski wrote:quoted
On 19/08/2022 12:13, Chunfeng Yun wrote:quoted
Add a property to set usb2 phy's pre-emphasis. Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com> --- Documentation/devicetree/bindings/phy/mediatek,tphy.yaml | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/Documentation/devicetree/bindings/phy/mediatek,tphy.yaml b/Documentation/devicetree/bindings/phy/mediatek,tphy.yaml index 848edfb1f677..aee2f3027371 100644--- a/Documentation/devicetree/bindings/phy/mediatek,tphy.yaml +++ b/Documentation/devicetree/bindings/phy/mediatek,tphy.yaml@@ -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: 3Instead 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? 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... Best regards, Krzysztof _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel