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% > > > + of the high-speed transmitter waveform. The range is from 0x0 to 0x3, > > + the default value is 0x1. Details can refer to TXRISETUNE0 bit of > > default: 1 > > Don't repeat constraints in free form text. Okay, will remove. > > > + USBNC_n_PHY_CFG1. > > + $ref: /schemas/types.yaml#/definitions/uint32 > > + minimum: 0x0 > > + maximum: 0x3 > > Why "samsung" prefix? If this is specific to samsung, make it > specific/narrowed like other properties. > > There are no Samsung compatibles here, so what is exactly here made by > Samsung? Which device? Reviewed the design, this is not specific to samsung. I will rename it to fsl,picophy-rise-fall-time-adjust since it's related to imx chip. Thanks, Xu Yang > > Best regards, > Krzysztof