[PATCH v3 0/3] dt-bindings: connector: usb: provide bindings for altmodes

[PATCH v3 0/3] dt-bindings: connector: usb: provide bindings for altmodes

[Dmitry Baryshkov]

In some cases we need a way to specify USB-C AltModes that can be
supportd on the particular USB-C connector. For example, x86 INT33FE
driver does this by populating fwnode properties internally. For the
Qualcomm Robotics RB5 platform (and several similar devices which use
Qualcomm PMIC TCPM) we have to put this information to the DT.

Provide the DT bindings for this kind of information and while we are at
it, change svid property to be 16-bit unsigned integer instead of a
simple u32.

NOTE: usage of u16 is not compatible with the recenty extended
qcom/qrb5165-rb5.dts DT file. I'm looking for the guidance from DT and
USB maintainers whether to retain u32 usage or it's better to switch to
u16.

Changes since v2:
- Inlined altmode definitions instead of having them under $defs (Rob)
- Explicity list permitted AltMode names (currenty only displayport is
  allowed) (Rob)

Changes since v1:
- Added type:object and fixed 'description' string in the altmodes-list
  definition.

Dmitry Baryshkov (3):
  dt-bindings: connector: usb: add altmodes description
  usb: typec: change altmode SVID to u16 entry
  arm64: dts: qcom: qrb5165-rb5: use u16 for DP altmode svid

 .../bindings/connector/usb-connector.yaml     | 29 +++++++++++++++++++
 arch/arm64/boot/dts/qcom/qrb5165-rb5.dts      |  2 +-
 drivers/platform/x86/intel/chtwc_int33fe.c    |  2 +-
 drivers/usb/typec/class.c                     |  5 ++--
 4 files changed, 34 insertions(+), 4 deletions(-)

-- 
2.42.0

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

[Dmitry Baryshkov]

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)$":
+        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>;
-- 
2.42.0

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

[Krzysztof Kozlowski]

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

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

[Dmitry Baryshkov]

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
>


-- 
With best wishes
Dmitry

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

[Rob Herring]

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>

[PATCH v3 2/3] usb: typec: change altmode SVID to u16 entry

[Dmitry Baryshkov]

As stated in the changelog for the commit 7b458a4c5d73 ("usb: typec: Add
typec_port_register_altmodes()"), the code should be adjusted according
to the AltMode bindings. As the SVID is 16 bits wide (according to the
USB PD Spec), use fwnode_property_read_u16() to read it.

Acked-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/platform/x86/intel/chtwc_int33fe.c | 2 +-
 drivers/usb/typec/class.c                  | 5 +++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/platform/x86/intel/chtwc_int33fe.c b/drivers/platform/x86/intel/chtwc_int33fe.c
index 848baecc1bb0..93f75ba1dafd 100644
--- a/drivers/platform/x86/intel/chtwc_int33fe.c
+++ b/drivers/platform/x86/intel/chtwc_int33fe.c
@@ -136,7 +136,7 @@ static const struct software_node altmodes_node = {
 };
 
 static const struct property_entry dp_altmode_properties[] = {
-	PROPERTY_ENTRY_U32("svid", 0xff01),
+	PROPERTY_ENTRY_U16("svid", 0xff01),
 	PROPERTY_ENTRY_U32("vdo", 0x0c0086),
 	{ }
 };
diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
index 6ec2a94e6fad..4251d44137b6 100644
--- a/drivers/usb/typec/class.c
+++ b/drivers/usb/typec/class.c
@@ -2238,7 +2238,8 @@ void typec_port_register_altmodes(struct typec_port *port,
 	struct typec_altmode_desc desc;
 	struct typec_altmode *alt;
 	size_t index = 0;
-	u32 svid, vdo;
+	u16 svid;
+	u32 vdo;
 	int ret;
 
 	altmodes_node = device_get_named_child_node(&port->dev, "altmodes");
@@ -2246,7 +2247,7 @@ void typec_port_register_altmodes(struct typec_port *port,
 		return; /* No altmodes specified */
 
 	fwnode_for_each_child_node(altmodes_node, child) {
-		ret = fwnode_property_read_u32(child, "svid", &svid);
+		ret = fwnode_property_read_u16(child, "svid", &svid);
 		if (ret) {
 			dev_err(&port->dev, "Error reading svid for altmode %s\n",
 				fwnode_get_name(child));
-- 
2.42.0

[PATCH v3 3/3] arm64: dts: qcom: qrb5165-rb5: use u16 for DP altmode svid

[Dmitry Baryshkov]

Follow the bindings and use 16-bit value for AltMode SVID instead of
using the full u32.

Fixes: b3dea914127e ("arm64: dts: qcom: qrb5165-rb5: enable DP altmode")
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 arch/arm64/boot/dts/qcom/qrb5165-rb5.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/qcom/qrb5165-rb5.dts b/arch/arm64/boot/dts/qcom/qrb5165-rb5.dts
index c8cd40a462a3..88b37ceb13ed 100644
--- a/arch/arm64/boot/dts/qcom/qrb5165-rb5.dts
+++ b/arch/arm64/boot/dts/qcom/qrb5165-rb5.dts
@@ -1425,7 +1425,7 @@ PDO_FIXED_USB_COMM |
 
 		altmodes {
 			displayport {
-				svid = <0xff01>;
+				svid = /bits/ 16 <0xff01>;
 				vdo = <0x00001c46>;
 			};
 		};
-- 
2.42.0