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[PATCH 1/3] dt-bindings: usb: fsa4480: Add data-lanes property to endpoint

Luca Weiss posted 3 patches 2 years, 2 months ago
There is a newer version of this series
[PATCH 1/3] dt-bindings: usb: fsa4480: Add data-lanes property to endpoint
Posted by Luca Weiss 2 years, 2 months ago 
Allow specifying data-lanes to reverse the SBU muxing orientation where
necessary by the hardware design.

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.
+            oneOf:
+              - items:
+                  - const: 0
+                  - const: 1
+                description: |
+                  Default AUX/SBU layout
+                  - AUX+ connected to SBU2
+                  - AUX- connected to SBU1
+              - items:
+                  - const: 1
+                  - const: 0
+                description: |
+                  Swapped AUX/SBU layout
+                  - AUX+ connected to SBU1
+                  - AUX- connected to SBU2
 
 required:
   - compatible

-- 
2.42.0
Re: [PATCH 1/3] dt-bindings: usb: fsa4480: Add data-lanes property to endpoint
Posted by Rob Herring 2 years, 2 months ago 
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.

Rob
Re: [PATCH 1/3] dt-bindings: usb: fsa4480: Add data-lanes property to endpoint
Posted by Neil Armstrong 2 years, 2 months ago 
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
Re: [PATCH 1/3] dt-bindings: usb: fsa4480: Add data-lanes property to endpoint
Posted by Rob Herring 2 years, 2 months ago 
On Mon, Oct 16, 2023 at 04:32:55PM +0200, Neil Armstrong wrote:
> 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.

I'd hate for this ASCII art to go to waste. Please add this detail to 
the commit message.

Rob

Patchew 2.1-devel-b67e4c2

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