Thread (8 messages) 8 messages, 3 authors, 2025-09-10

Re: [PATCH RFC 1/2] dt-bindings: phy: rockchip-usbdp: add improved ports scheme

From: Dmitry Baryshkov <hidden>
Date: 2025-09-06 19:24:59
Also in: linux-devicetree, linux-phy, linux-rockchip, lkml

On Thu, Sep 04, 2025 at 08:26:02PM +0200, Sebastian Reichel wrote:
quoted hunk ↗ jump to hunk
Currently the Rockchip USBDP PHY as a very simply port scheme: It just
offers a single port, which is supposed to point towards the connector.
Usually with 2 endpoints, one for the USB-C superspeed port and one for
the USB-C SBU port.

This scheme is not good enough to properly handle DP AltMode, so add
a new scheme, which has separate ports for everything. This has been
modelled after the Qualcomm QMP USB4-USB3-DP PHY controller binding
with a slight difference that there is an additional port for the
USB-C SBU port as the Rockchip USB-DP PHY also contains the mux.

Signed-off-by: Sebastian Reichel <redacted>
---
 .../bindings/phy/phy-rockchip-usbdp.yaml           | 23 ++++++++++++++++++++++
 1 file changed, 23 insertions(+)
diff --git a/Documentation/devicetree/bindings/phy/phy-rockchip-usbdp.yaml b/Documentation/devicetree/bindings/phy/phy-rockchip-usbdp.yaml
index 8b7059d5b1826fdec5170cf78d6e27f2bd6766bb..f728acf057e4046a4d254ee687af3451f17bcd01 100644
--- a/Documentation/devicetree/bindings/phy/phy-rockchip-usbdp.yaml
+++ b/Documentation/devicetree/bindings/phy/phy-rockchip-usbdp.yaml
@@ -114,6 +114,29 @@ properties:
       A port node to link the PHY to a TypeC controller for the purpose of
       handling orientation switching.
 
+  ports:
+    $ref: /schemas/graph.yaml#/properties/ports
+    properties:
+      port@0:
+        $ref: /schemas/graph.yaml#/properties/port
+        description:
+          Output endpoint of the PHY for USB (or DP when configured into 4 lane
+          mode), which should point to the superspeed port of a USB connector.
What abourt USB+DP mode, where each one gets 2 lanes?
+
+      port@1:
+        $ref: /schemas/graph.yaml#/properties/port
+        description: Incoming endpoint from the USB controller
+
+      port@2:
+        $ref: /schemas/graph.yaml#/properties/port
+        description: Incoming endpoint from the DisplayPort controller
+
+      port@3:
+        $ref: /schemas/graph.yaml#/properties/port
+        description:
+          Output endpoint of the PHY for DP, which should either point to the
+          SBU port of a USB-C connector or a DisplayPort connector input port.
I would suggest describing this port as 'DisplayPort AUX signals to be
connected to the SBU port of a USB-C connector (maybe through the
additinal mux, switch or retimer)'. It should not be confused with the
actual DisplayPort signals (as those go through the port@0).

In the Qualcomm world we currently do not describe this link from the
PHY to the gpio-mux or retimer, but I think we will have to do that
soon.
+
 required:
   - compatible
   - reg

-- 
2.50.1


_______________________________________________
Linux-rockchip mailing list
Linux-rockchip@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-rockchip
-- 
With best wishes
Dmitry
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help