[PATCH v8 1/3] dt-bindings: phy: qcom,usb-snps-femto-v2: Add phy override params bindings
Krishna Kurapati PSSNV
quic_kriskura at quicinc.com
Wed Jun 8 04:03:04 PDT 2022
On 6/8/2022 3:06 PM, Krzysztof Kozlowski wrote:
> On 01/06/2022 08:56, Krishna Kurapati wrote:
>> From: Sandeep Maheswaram <quic_c_sanm at quicinc.com>
>>
>> Add device tree bindings for SNPS phy tuning parameters.
>>
>> Signed-off-by: Sandeep Maheswaram <quic_c_sanm at quicinc.com>
>> Signed-off-by: Krishna Kurapati <quic_kriskura at quicinc.com>
>> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski at linaro.org>
>> ---
>> .../bindings/phy/qcom,usb-snps-femto-v2.yaml | 96 ++++++++++++++++++++++
>> 1 file changed, 96 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/phy/qcom,usb-snps-femto-v2.yaml b/Documentation/devicetree/bindings/phy/qcom,usb-snps-femto-v2.yaml
>> index 1ce251d..daeeb04 100644
>> --- a/Documentation/devicetree/bindings/phy/qcom,usb-snps-femto-v2.yaml
>> +++ b/Documentation/devicetree/bindings/phy/qcom,usb-snps-femto-v2.yaml
>> @@ -53,6 +53,102 @@ properties:
>> vdda33-supply:
>> description: phandle to the regulator 3.3V supply node.
>>
>> + qcom,hs-disconnect-bp:
>> + description:
>> + This adjusts the voltage level for the threshold used to
>> + detect a disconnect event at the host. Possible values are.
>> + The values defined are in multiples of basis points (1bp = 0.01%).
>> + The hardware accepts only discrete values. The value closest to the
>> + provided input will be chosen as the override value for this param.
>> + minimum: -272
>> + maximum: 2156
>> +
>> + qcom,squelch-detector-bp:
>> + description:
>> + This adjusts the voltage level for the threshold used to
>> + detect valid high-speed data.
>> + The values defined are in multiples of basis points (1bp = 0.01%).
>> + The hardware accepts only discrete values. The value closest to the
>> + provided input will be chosen as the override value for this param.
>> + minimum: -2090
>> + maximum: 1590
>> +
>> + qcom,hs-amplitude-bp:
>> + description:
>> + This adjusts the high-speed DC level voltage.
>> + The values defined are in multiples of basis points (1bp = 0.01%).
>> + The hardware accepts only discrete values. The value closest to the
>> + provided input will be chosen as the override value for this param.
>> + minimum: -660
>> + maximum: 2670
>> +
>> + qcom,pre-emphasis-duration-bp:
>> + description:
>> + This signal controls the duration for which the
>> + HS pre-emphasis current is sourced onto DP<#> or DM<#>.
>> + The HS Transmitter pre-emphasis duration is defined in terms of
>> + unit amounts. One unit of pre-emphasis duration is approximately
>> + 650 ps and is defined as 1X pre-emphasis duration.
>> + The values defined are in multiples of basis points (1bp = 0.01%).
>> + The hardware accepts only discrete values. The value closest to the
>> + provided input will be chosen as the override value for this param.
>> + minimum: 10000
>> + maximum: 20000
>> +
>> + qcom,pre-emphasis-amplitude-bp:
>> + description:
>> + This signal controls the amount of current sourced to
>> + DP<#> and DM<#> after a J-to-K or K-to-J transition.
>> + The HS Transmitter pre-emphasis current is defined in terms of unit
>> + amounts. One unit amount is approximately 2 mA and is defined as
>> + 1X pre-emphasis current.
>> + The values defined are in multiples of basis points (1bp = 0.01%).
>> + The hardware accepts only discrete values. The value closest to the
>> + provided input will be chosen as the override value for this param.
>> + minimum: 10000
>> + maximum: 40000
>> +
>> + qcom,hs-rise-fall-time-bp:
>> + description:
>> + This adjusts the rise/fall times of the high-speed waveform.
>> + The values defined are in multiples of basis points (1bp = 0.01%).
>> + The hardware accepts only discrete values. The value closest to the
>> + provided input will be chosen as the override value for this param.
>> + minimum: -4100
>> + maximum: 5430
>> +
>> + qcom,hs-crossover-voltage-microvolt:
>> + description:
>> + This adjusts the voltage at which the DP<#> and DM<#>
>> + signals cross while transmitting in HS mode.
>> + The values defined are in milli volts.
> It's not accurate anymore - it's microvolt. I propose to skip this one
> sentence, because unit is obvious from the type.
>
>> + maximum: 28000
>> +
>> + qcom,hs-output-impedance-micro-ohms:
>> + description:
>> + In some applications, there can be significant series resistance
>> + on the D+ and D- paths between the transceiver and cable. This adjusts
>> + the driver source impedance to compensate for added series
>> + resistance on the USB. The values defined are in milli ohms.
> The same. Other places might need similar change.
>
> Best regards,
> Krzysztof
Hi Krzysztof,
Sure, will modify the description for all the params.
Regards,
Krishna,
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