[PATCH v4 1/2] dt-bindings: usb: cdns3: Add no_drd property

[Pawel Laszczak via B4 Relay <devnull+pawell.cadence.com@kernel.org>]

From: Pawel Laszczak <pawell@cadence.com>

Introduce a new boolean property 'no_drd' for Cadence USBSS/USBSSP
controllers.

Some hardware configurations of this controller are designed without
the Dual-Role Device (DRD) register block or have it inaccessible.
In such cases, the driver must skip all OTG/DRD register accesses
to avoid bus errors and cannot rely on hardware-based role switching.

To accommodate these configurations, also relax the requirements for
the 'reg' and 'interrupts' properties, making the 'otg' resources
optional.

Signed-off-by: Pawel Laszczak <pawell@cadence.com>
---
 Documentation/devicetree/bindings/usb/cdns,usb3.yaml | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/usb/cdns,usb3.yaml b/Documentation/devicetree/bindings/usb/cdns,usb3.yaml
index 2d95fb7321af..8c7dc81708fb 100644
--- a/Documentation/devicetree/bindings/usb/cdns,usb3.yaml
+++ b/Documentation/devicetree/bindings/usb/cdns,usb3.yaml
@@ -20,19 +20,21 @@ properties:
     const: cdns,usb3
 
   reg:
+    minItems: 2
     items:
       - description: OTG controller registers
       - description: XHCI Host controller registers
       - description: DEVICE controller registers
 
   reg-names:
+    minItems: 2
     items:
       - const: otg
       - const: xhci
       - const: dev
 
   interrupts:
-    minItems: 3
+    minItems: 2
     items:
       - description: XHCI host controller interrupt
       - description: Device controller interrupt
@@ -41,7 +43,7 @@ properties:
                      cleared by xhci core, this interrupt is optional
 
   interrupt-names:
-    minItems: 3
+    minItems: 2
     items:
       - const: host
       - const: peripheral
@@ -79,6 +81,13 @@ properties:
     description: Enable resetting of PHY if Rx fail is detected
     type: boolean
 
+  no_drd:
+    description:
+      Indicates that the Dual-Role Device (DRD) register block is not
+      implemented or is inaccessible. In this case, the controller
+      must operate in a fixed peripheral or host mode.
+    type: boolean
+
 dependencies:
   port: [ usb-role-switch ]
 

-- 
2.43.0