Commit 6e59b5ae authored by Amelie Delaunay's avatar Amelie Delaunay Committed by Vinod Koul
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dt-bindings: phy: phy-stm32-usbphyc: add optional phy tuning properties 



This patch adds the description of new optional phy tuning properties
for usbphyc phy sub nodes.

Signed-off-by: default avatarAmelie Delaunay <amelie.delaunay@foss.st.com>
Reviewed-by: default avatarRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211015161427.220784-3-amelie.delaunay@foss.st.com


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent 95e38c17

Documentation/devicetree/bindings/phy/phy-stm32-usbphyc.yaml

+129 −0
Original line number Diff line number Diff line
@@ -81,6 +81,119 @@ patternProperties: 
        properties:

          vbus-supply: true



      # It can be necessary to adjust the PHY settings to compensate parasitics, which can be due

      # to USB connector/receptacle, routing, ESD protection component,... Here is the list of

      # all optional parameters to tune the interface of the PHY (HS for High-Speed, FS for Full-

      # Speed, LS for Low-Speed)



      st,current-boost-microamp:

        description: Current boosting in uA

        enum: [ 1000, 2000 ]



      st,no-lsfs-fb-cap:

        description: Disables the LS/FS feedback capacitor

        type: boolean



      st,decrease-hs-slew-rate:

        description: Decreases the HS driver slew rate by 10%

        type: boolean



      st,tune-hs-dc-level:

        description: |

          Tunes the HS driver DC level

          - <0> normal level

          - <1> increases the level by 5 to 7 mV

          - <2> increases the level by 10 to 14 mV

          - <3> decreases the level by 5 to 7 mV

        $ref: /schemas/types.yaml#/definitions/uint32

        minimum: 0

        maximum: 3

        default: 0



      st,enable-fs-rftime-tuning:

        description: Enables the FS rise/fall tuning option

        type: boolean



      st,enable-hs-rftime-reduction:

        description: Enables the HS rise/fall reduction feature

        type: boolean



      st,trim-hs-current:

        description: |

          Controls HS driver current trimming for choke compensation

          - <0> = 18.87 mA target current / nominal + 0%

          - <1> = 19.165 mA target current / nominal + 1.56%

          - <2> = 19.46 mA target current / nominal + 3.12%

          - <3> = 19.755 mA target current / nominal + 4.68%

          - <4> = 20.05 mA target current / nominal + 6.24%

          - <5> = 20.345 mA target current / nominal + 7.8%

          - <6> = 20.64 mA target current / nominal + 9.36%

          - <7> = 20.935 mA target current / nominal + 10.92%

          - <8> = 21.23 mA target current / nominal + 12.48%

          - <9> = 21.525 mA target current / nominal + 14.04%

          - <10> = 21.82 mA target current / nominal + 15.6%

          - <11> = 22.115 mA target current / nominal + 17.16%

          - <12> = 22.458 mA target current / nominal + 19.01%

          - <13> = 22.755 mA target current / nominal + 20.58%

          - <14> = 23.052 mA target current / nominal + 22.16%

          - <15> = 23.348 mA target current / nominal + 23.73%

        $ref: /schemas/types.yaml#/definitions/uint32

        minimum: 0

        maximum: 15

        default: 0



      st,trim-hs-impedance:

        description: |

          Controls HS driver impedance tuning for choke compensation

          - <0> = no impedance offset

          - <1> = reduce the impedance by 2 ohms

          - <2> = reduce the impedance by 4 ohms

          - <3> = reduce the impedance by 6 ohms

        $ref: /schemas/types.yaml#/definitions/uint32

        minimum: 0

        maximum: 3

        default: 0



      st,tune-squelch-level:

        description: |

          Tunes the squelch DC threshold value

          - <0> = no shift in threshold

          - <1> = threshold shift by +7 mV

          - <2> = threshold shift by -5 mV

          - <3> = threshold shift by +14 mV

        $ref: /schemas/types.yaml#/definitions/uint32

        minimum: 0

        maximum: 3

        default: 0



      st,enable-hs-rx-gain-eq:

        description: Enables the HS Rx gain equalizer

        type: boolean



      st,tune-hs-rx-offset:

        description: |

          Adjusts the HS Rx offset

          - <0> = no offset

          - <1> = offset of +5 mV

          - <2> = offset of +10 mV

          - <3> = offset of -5 mV

        $ref: /schemas/types.yaml#/definitions/uint32

        minimum: 0

        maximum: 3

        default: 0



      st,no-hs-ftime-ctrl:

        description: Disables the HS fall time control of single ended signals during pre-emphasis

        type: boolean



      st,no-lsfs-sc:

        description: Disables the short circuit protection in LS/FS driver

        type: boolean



      st,enable-hs-tx-staggering:

        description: Enables the basic staggering in HS Tx mode

        type: boolean



    allOf:

      - if:

          properties:
@@ -137,6 +250,14 @@ examples: 
            reg = <0>;

            phy-supply = <&vdd_usb>;

            #phy-cells = <0>;

            st,tune-hs-dc-level = <2>;

            st,enable-fs-rftime-tuning;

            st,enable-hs-rftime-reduction;

            st,trim-hs-current = <15>;

            st,trim-hs-impedance = <1>;

            st,tune-squelch-level = <3>;

            st,tune-hs-rx-offset = <2>;

            st,no-lsfs-sc;

            connector {

                compatible = "usb-a-connector";

                vbus-supply = <&vbus_sw>;
@@ -147,6 +268,14 @@ examples: 
            reg = <1>;

            phy-supply = <&vdd_usb>;

            #phy-cells = <1>;

            st,tune-hs-dc-level = <2>;

            st,enable-fs-rftime-tuning;

            st,enable-hs-rftime-reduction;

            st,trim-hs-current = <15>;

            st,trim-hs-impedance = <1>;

            st,tune-squelch-level = <3>;

            st,tune-hs-rx-offset = <2>;

            st,no-lsfs-sc;

        };

    };

...