From 6e59b5aea2f8b55e1c629ac35c147dfc14c418da Mon Sep 17 00:00:00 2001 From: Amelie Delaunay Date: Fri, 15 Oct 2021 18:14:26 +0200 Subject: [PATCH] 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: Amelie Delaunay Reviewed-by: Rob Herring Link: https://lore.kernel.org/r/20211015161427.220784-3-amelie.delaunay@foss.st.com Signed-off-by: Vinod Koul --- .../devicetree/bindings/phy/phy-stm32-usbphyc.yaml | 129 +++++++++++++++++++++ 1 file changed, 129 insertions(+) diff --git a/Documentation/devicetree/bindings/phy/phy-stm32-usbphyc.yaml b/Documentation/devicetree/bindings/phy/phy-stm32-usbphyc.yaml index 3329f1d..2251283 100644 --- a/Documentation/devicetree/bindings/phy/phy-stm32-usbphyc.yaml +++ b/Documentation/devicetree/bindings/phy/phy-stm32-usbphyc.yaml @@ -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; }; }; ... -- 2.7.4