On 27/06/2023 05:10, Xu Yang wrote: > Hi Krzysztof, > >> -----Original Message----- >> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> >> Sent: Monday, June 26, 2023 11:45 PM >> To: Xu Yang <xu.yang_2@xxxxxxx>; peter.chen@xxxxxxxxxx; robh+dt@xxxxxxxxxx; krzysztof.kozlowski+dt@xxxxxxxxxx; >> gregkh@xxxxxxxxxxxxxxxxxxx >> Cc: conor+dt@xxxxxxxxxx; shawnguo@xxxxxxxxxx; s.hauer@xxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx>; Peng Fan >> <peng.fan@xxxxxxx>; linux-usb@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; Jun Li <jun.li@xxxxxxx> >> Subject: [EXT] Re: [PATCH 2/3] dt-bindings: usb: ci-hdrc-usb2: add samsung,picophy-rise-fall-time-adjust property >> >> Caution: This is an external email. Please take care when clicking links or opening attachments. When in doubt, report the >> message using the 'Report this email' button >> >> >> On 26/06/2023 11:29, Xu Yang wrote: >>> The samsung,picophy-rise-fall-time-adjust property can help to adjust the >>> rise/fall times of the high-speed transmitter waveform. The value can be >>> 0~3. >>> >>> Signed-off-by: Xu Yang <xu.yang_2@xxxxxxx> >>> --- >>> .../devicetree/bindings/usb/ci-hdrc-usb2.yaml | 10 ++++++++++ >>> 1 file changed, 10 insertions(+) >>> >>> diff --git a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.yaml b/Documentation/devicetree/bindings/usb/ci- >> hdrc-usb2.yaml >>> index 782402800d4a..d84c66c342ac 100644 >>> --- a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.yaml >>> +++ b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.yaml >>> @@ -292,6 +292,16 @@ properties: >>> minimum: 0x0 >>> maximum: 0xf >>> >>> + samsung,picophy-rise-fall-time-adjust: >>> + description: >>> + HS Transmitter Rise/Fall Time Adjustment. Adjust the rise/fall times >> >> Adjust with/by what? What are the units? > > This property is used to adjust the rise/fall time of the high-speed > transmitter waveform. It has no unit. According to the description of > USBNC_n_PHY_CFG1 register, the rise/fall time will be increased or > decreased by a certain percentage relative to design default time if > a value is given to this property. > > The actions as below: > - 0: -10% > - 1: design default > - 2: +15% > - 3: +20% Include it then in the description or even make the property -percent: https://github.com/devicetree-org/dt-schema/blob/main/dtschema/schemas/property-units.yaml Best regards, Krzysztof
