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From:   Jayesh Choudhary <j-choudhary@ti.com>
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Subject: [PATCH v2 1/2] dt-bindings: drm/bridge: Add no-hpd property
Date:   Wed, 5 Apr 2023 19:54:39 +0530
Message-ID: <20230405142440.191939-2-j-choudhary@ti.com>
In-Reply-To: <20230405142440.191939-1-j-choudhary@ti.com>
References: <20230405142440.191939-1-j-choudhary@ti.com>
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From: Rahul T R <r-ravikumar@ti.com>

The mhdp bridge can work without its HPD pin hooked up to the connector,
but the current bridge driver throws an error when hpd line is not
connected to the connector. For such cases, we need an indication for
no-hpd, using which we can bypass the hpd detection and instead use the
auxiliary channels connected to the DP connector to confirm the
connection.
So add no-hpd property to the bindings, to disable hpd when not
connected or unusable.

Signed-off-by: Rahul T R <r-ravikumar@ti.com>
Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
---
 .../devicetree/bindings/display/bridge/cdns,mhdp8546.yaml   | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml b/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml
index c2b369456e4e..3a6c6d837593 100644
--- a/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml
+++ b/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml
@@ -57,6 +57,12 @@ properties:
   interrupts:
     maxItems: 1
 
+  cdns,no-hpd:
+    type: boolean
+    description:
+      Set if the HPD line on the bridge isn't hooked up to anything or is
+      otherwise unusable.
+
   ports:
     $ref: /schemas/graph.yaml#/properties/ports
 
-- 
2.25.1