[v4 1/3] dt-bindings: phy: qcom,usb-snps-femto-v2: Add phy override params bindings

Krzysztof Kozlowski krzysztof.kozlowski at linaro.org
Thu May 12 03:30:20 PDT 2022


On 12/05/2022 07:57, Krishna Kurapati PSSNV wrote:
> 
> On 5/11/2022 11:49 PM, Krzysztof Kozlowski wrote:
>> On 11/05/2022 17:26, 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>
>>> ---
>>>   .../bindings/phy/qcom,usb-snps-femto-v2.yaml       | 87 ++++++++++++++++++++++
>>>   1 file changed, 87 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..70efffe 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 +53,93 @@ properties:
>>>     vdda33-supply:
>>>       description: phandle to the regulator 3.3V supply node.
>>>   
>>> +  qcom,hs-disconnect-bps:
>>> +    $ref: /schemas/types.yaml#/definitions/int32
>>> +    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%).
>> This means there is some minimum and maximum (100%)?
> 
> Hi Krzystof,
> 
> Yes there are max and min for each parameter (not necessarily 0%/100%)
> 
> As an example if we take squelch detector threshold, the register value 
> vs actual percentage changer as per data book is as follows :
> 
> % change in voltage    |     corresponding reg value
> 
>   -20.90%                        |    7
>   -15.60%                        |    6
> -10.30%                         |    5
> -5.30%                           |    4
> 0%                                  |    3
> 5.30%                            |    2
> 10.60%                          |    1
> 15.90%                          |    0
> 
> Here the min and max are 15.9% to -20.9%
> 
> The min and max differ for each parameter and might not be necessarily 
> 0% and 100%

Then it seems possible to define minimum and maximum values - please add
them ("minimum: xxxx").


Best regards,
Krzysztof



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