diff mbox series

[v3,1/3] dt-bindings: connector: usb: add altmodes description

Message ID 20231120224919.2293730-2-dmitry.baryshkov@linaro.org (mailing list archive)
State Superseded
Headers show
Series dt-bindings: connector: usb: provide bindings for altmodes | expand

Commit Message

Dmitry Baryshkov Nov. 20, 2023, 10 p.m. UTC
Add description of the USB-C AltModes supported on the particular USB-C
connector. This is required for devices like Qualcomm Robotics RB5,
which have no other way to express alternative modes supported by the
hardware platform.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 .../bindings/connector/usb-connector.yaml     | 29 +++++++++++++++++++
 1 file changed, 29 insertions(+)

Comments

Krzysztof Kozlowski Nov. 21, 2023, 8:31 a.m. UTC | #1
On 20/11/2023 23:00, Dmitry Baryshkov wrote:
> Add description of the USB-C AltModes supported on the particular USB-C
> connector. This is required for devices like Qualcomm Robotics RB5,
> which have no other way to express alternative modes supported by the
> hardware platform.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
>  .../bindings/connector/usb-connector.yaml     | 29 +++++++++++++++++++
>  1 file changed, 29 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/connector/usb-connector.yaml b/Documentation/devicetree/bindings/connector/usb-connector.yaml
> index 7c8a3e8430d3..c1aaac861d9d 100644
> --- a/Documentation/devicetree/bindings/connector/usb-connector.yaml
> +++ b/Documentation/devicetree/bindings/connector/usb-connector.yaml
> @@ -171,6 +171,28 @@ properties:
>        offer the power, Capability Mismatch is set. Required for power sink and
>        power dual role.
>  
> +  altmodes:
> +    type: object
> +    description: List of Alternative Modes supported by the schematics on the
> +      particular device. This is only necessary if there are no other means to
> +      discover supported alternative modes (e.g. through the UCSI firmware
> +      interface).
> +
> +    patternProperties:
> +      "^(displayport)$":

This is just a property, so should be under "properties:".

The rest looks good to me, but I don't know USB that much to judge.

Best regards,
Krzysztof
Dmitry Baryshkov Nov. 21, 2023, 9:19 a.m. UTC | #2
On Tue, 21 Nov 2023 at 10:31, Krzysztof Kozlowski
<krzysztof.kozlowski@linaro.org> wrote:
>
> On 20/11/2023 23:00, Dmitry Baryshkov wrote:
> > Add description of the USB-C AltModes supported on the particular USB-C
> > connector. This is required for devices like Qualcomm Robotics RB5,
> > which have no other way to express alternative modes supported by the
> > hardware platform.
> >
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > ---
> >  .../bindings/connector/usb-connector.yaml     | 29 +++++++++++++++++++
> >  1 file changed, 29 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/connector/usb-connector.yaml b/Documentation/devicetree/bindings/connector/usb-connector.yaml
> > index 7c8a3e8430d3..c1aaac861d9d 100644
> > --- a/Documentation/devicetree/bindings/connector/usb-connector.yaml
> > +++ b/Documentation/devicetree/bindings/connector/usb-connector.yaml
> > @@ -171,6 +171,28 @@ properties:
> >        offer the power, Capability Mismatch is set. Required for power sink and
> >        power dual role.
> >
> > +  altmodes:
> > +    type: object
> > +    description: List of Alternative Modes supported by the schematics on the
> > +      particular device. This is only necessary if there are no other means to
> > +      discover supported alternative modes (e.g. through the UCSI firmware
> > +      interface).
> > +
> > +    patternProperties:
> > +      "^(displayport)$":
>
> This is just a property, so should be under "properties:".

Having it under properties would make adding new altmodes harder.

Inherently it should become something like
"^(displayport|virtuallink|thunderbolt)$".

>
> The rest looks good to me, but I don't know USB that much to judge.
>
> Best regards,
> Krzysztof
>
Rob Herring (Arm) Nov. 27, 2023, 6:50 p.m. UTC | #3
On Tue, Nov 21, 2023 at 12:00:18AM +0200, Dmitry Baryshkov wrote:
> Add description of the USB-C AltModes supported on the particular USB-C
> connector. This is required for devices like Qualcomm Robotics RB5,
> which have no other way to express alternative modes supported by the
> hardware platform.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
>  .../bindings/connector/usb-connector.yaml     | 29 +++++++++++++++++++
>  1 file changed, 29 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/connector/usb-connector.yaml b/Documentation/devicetree/bindings/connector/usb-connector.yaml
> index 7c8a3e8430d3..c1aaac861d9d 100644
> --- a/Documentation/devicetree/bindings/connector/usb-connector.yaml
> +++ b/Documentation/devicetree/bindings/connector/usb-connector.yaml
> @@ -171,6 +171,28 @@ properties:
>        offer the power, Capability Mismatch is set. Required for power sink and
>        power dual role.
>  
> +  altmodes:
> +    type: object
> +    description: List of Alternative Modes supported by the schematics on the
> +      particular device. This is only necessary if there are no other means to
> +      discover supported alternative modes (e.g. through the UCSI firmware
> +      interface).

Move additionalProperties here.

> +
> +    patternProperties:
> +      "^(displayport)$":
> +        type: object
> +        description:
> +          A single USB-C Alternative Mode as supported by the USB-C connector logic.

Move additionalProperties here.

And a blank line

> +        properties:
> +          svid:
> +            $ref: /schemas/types.yaml#/definitions/uint16
> +            description: Unique value assigned by USB-IF to the Vendor / AltMode.

blank line

Since you've constrained the node name, then the only possible value 
here is 0xff01?

OTOH, I don't know that we want to enumerate all possible values here 
especially if there could be lots of vendor modes. But then again, maybe 
better to just wait and see if that becomes a problem.

With those nits fixed,

Reviewed-by: Rob Herring <robh@kernel.org>
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/connector/usb-connector.yaml b/Documentation/devicetree/bindings/connector/usb-connector.yaml
index 7c8a3e8430d3..c1aaac861d9d 100644
--- a/Documentation/devicetree/bindings/connector/usb-connector.yaml
+++ b/Documentation/devicetree/bindings/connector/usb-connector.yaml
@@ -171,6 +171,28 @@  properties:
       offer the power, Capability Mismatch is set. Required for power sink and
       power dual role.
 
+  altmodes:
+    type: object
+    description: List of Alternative Modes supported by the schematics on the
+      particular device. This is only necessary if there are no other means to
+      discover supported alternative modes (e.g. through the UCSI firmware
+      interface).
+
+    patternProperties:
+      "^(displayport)$":
+        type: object
+        description:
+          A single USB-C Alternative Mode as supported by the USB-C connector logic.
+        properties:
+          svid:
+            $ref: /schemas/types.yaml#/definitions/uint16
+            description: Unique value assigned by USB-IF to the Vendor / AltMode.
+          vdo:
+            $ref: /schemas/types.yaml#/definitions/uint32
+            description: VDO returned by Discover Modes USB PD command.
+        additionalProperties: false
+    additionalProperties: false
+
   port:
     $ref: /schemas/graph.yaml#/properties/port
     description: OF graph bindings modeling a data bus to the connector, e.g.
@@ -289,6 +311,13 @@  examples:
             compatible = "usb-c-connector";
             label = "USB-C";
 
+            altmodes {
+                displayport {
+                    svid = /bits/ 16 <0xff01>;
+                    vdo = <0x00001c46>;
+                };
+            };
+
             ports {
                 #address-cells = <1>;
                 #size-cells = <0>;