Messages in this thread | | | Date | Mon, 16 Oct 2023 16:32:55 +0200 | From | Neil Armstrong <> | Subject | Re: [PATCH 1/3] dt-bindings: usb: fsa4480: Add data-lanes property to endpoint |
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On 16/10/2023 16:22, Rob Herring wrote: > On Fri, Oct 13, 2023 at 01:38:05PM +0200, Luca Weiss wrote: >> Allow specifying data-lanes to reverse the SBU muxing orientation where >> necessary by the hardware design. > > What situation in the hardware design makes this necessary. Please > describe the problem. > >> >> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com> >> --- >> .../devicetree/bindings/usb/fcs,fsa4480.yaml | 29 +++++++++++++++++++++- >> 1 file changed, 28 insertions(+), 1 deletion(-) >> >> diff --git a/Documentation/devicetree/bindings/usb/fcs,fsa4480.yaml b/Documentation/devicetree/bindings/usb/fcs,fsa4480.yaml >> index f6e7a5c1ff0b..86f6d633c2fb 100644 >> --- a/Documentation/devicetree/bindings/usb/fcs,fsa4480.yaml >> +++ b/Documentation/devicetree/bindings/usb/fcs,fsa4480.yaml >> @@ -32,10 +32,37 @@ properties: >> type: boolean >> >> port: >> - $ref: /schemas/graph.yaml#/properties/port >> + $ref: /schemas/graph.yaml#/$defs/port-base >> description: >> A port node to link the FSA4480 to a TypeC controller for the purpose of >> handling altmode muxing and orientation switching. >> + unevaluatedProperties: false >> + >> + properties: >> + endpoint: >> + $ref: /schemas/graph.yaml#/$defs/endpoint-base >> + unevaluatedProperties: false >> + >> + properties: >> + data-lanes: >> + $ref: /schemas/types.yaml#/definitions/uint32-array >> + description: >> + Specifies how the AUX+/- lines are connected to SBU1/2. > > Doesn't this depend on the connector orientation? Or it is both that and > the lines can be swapped on the PCB? > > Seems like an abuse of data-lanes which already has a definition which > is not about swapping + and - differential lanes.
The FSA acts as a mux between DP AUX, Audio lanes on one side and the USB-C SBU lanes on the other side. _______ ______ | | | |-- HP --| | |-- MIC --| |or SoC | | MUX |-- SBU1 ---> To the USB-C Codec |-- AUX+ --| |-- SBU2 ---> connected |-- AUX- --| | ______| |____ |
The SBU1 & SBU2 are connected to the USB-C connector, and the actual orientation to the connected devices/cable/whatever is determined by the TPCM and the MUX in the FSA4480 with be dynamically changed according to the CC1/CC2 detection and PD alt mode.
But on the other side the orientation of the AUX+/AUX- connected to the SoC is not tied to the USB-C orientation but how it's routed on the PCB.
This describes how the AUX+/AUX- are physically routed to the FSA4480 chip.
Neil
> > Rob
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