[PATCH v1 0/2] ARM: tegra: document Tegra20 HDMI port

[PATCH v1 0/2] ARM: tegra: document Tegra20 HDMI port

[Svyatoslav Ryhel]

Document port which can be used in the HDMI to model it using OF
graph.

Svyatoslav Ryhel (2):
  dt-bindings: display: tegra: document Tegra20 HDMI port
  ARM: tegra: transformers: add connector node

 .../display/tegra/nvidia,tegra20-hdmi.yaml    | 13 +++++++++--
 .../tegra20-asus-transformer-common.dtsi      | 22 ++++++++++++++++---
 .../boot/dts/nvidia/tegra30-asus-tf600t.dts   | 21 ++++++++++++++++--
 .../tegra30-asus-transformer-common.dtsi      | 21 ++++++++++++++++--
 4 files changed, 68 insertions(+), 9 deletions(-)

-- 
2.51.0

[PATCH v1 1/2] dt-bindings: display: tegra: document Tegra20 HDMI port

[Svyatoslav Ryhel]

Tegra HDMI can be modeled using an OF graph. Reflect this in the bindings.

Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
---
 .../bindings/display/tegra/nvidia,tegra20-hdmi.yaml | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-hdmi.yaml b/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-hdmi.yaml
index f77197e4869f..f33b700bf0ee 100644
--- a/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-hdmi.yaml
+++ b/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-hdmi.yaml
@@ -82,6 +82,10 @@ properties:
     description: phandle of a display panel
     $ref: /schemas/types.yaml#/definitions/phandle
 
+  port:
+    description: connection to controller receiving HDMI signals
+    $ref: /schemas/graph.yaml#/properties/port
+
   "#sound-dai-cells":
     const: 0
 
@@ -97,8 +101,13 @@ required:
   - reset-names
   - pll-supply
   - vdd-supply
-  - nvidia,ddc-i2c-bus
-  - nvidia,hpd-gpio
+
+anyOf:
+  - required:
+    - nvidia,ddc-i2c-bus
+    - nvidia,hpd-gpio
+  - required:
+    - port
 
 examples:
   - |
-- 
2.51.0

[PATCH v1 2/2] ARM: tegra: transformers: add connector node

[Svyatoslav Ryhel]

All ASUS Transformers have micro-HDMI connector directly available. After
Tegra HDMI got bridge/connector support, we should use connector framework
for proper HW description.

Tested-by: Andreas Westman Dorcsak <hedmoo@yahoo.com> # ASUS TF T30
Tested-by: Robert Eckelmann <longnoserob@gmail.com> # ASUS TF101 T20
Tested-by: Svyatoslav Ryhel <clamor95@gmail.com> # ASUS TF201 T30
Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
---
 .../tegra20-asus-transformer-common.dtsi      | 22 ++++++++++++++++---
 .../boot/dts/nvidia/tegra30-asus-tf600t.dts   | 21 ++++++++++++++++--
 .../tegra30-asus-transformer-common.dtsi      | 21 ++++++++++++++++--
 3 files changed, 57 insertions(+), 7 deletions(-)

diff --git a/arch/arm/boot/dts/nvidia/tegra20-asus-transformer-common.dtsi b/arch/arm/boot/dts/nvidia/tegra20-asus-transformer-common.dtsi
index 73c7ee378865..51d99998d836 100644
--- a/arch/arm/boot/dts/nvidia/tegra20-asus-transformer-common.dtsi
+++ b/arch/arm/boot/dts/nvidia/tegra20-asus-transformer-common.dtsi
@@ -79,9 +79,11 @@ hdmi@54280000 {
 			pll-supply = <&hdmi_pll_reg>;
 			hdmi-supply = <&vdd_hdmi_en>;
 
-			nvidia,ddc-i2c-bus = <&hdmi_ddc>;
-			nvidia,hpd-gpio = <&gpio TEGRA_GPIO(N, 7)
-				GPIO_ACTIVE_HIGH>;
+			port {
+				hdmi_out: endpoint {
+					remote-endpoint = <&connector_in>;
+				};
+			};
 		};
 	};
 
@@ -951,6 +953,20 @@ clk32k_in: clock-32k-in {
 		#clock-cells = <0>;
 	};
 
+	connector {
+		compatible = "hdmi-connector";
+		type = "d";
+
+		hpd-gpios = <&gpio TEGRA_GPIO(N, 7) GPIO_ACTIVE_HIGH>;
+		ddc-i2c-bus = <&hdmi_ddc>;
+
+		port {
+			connector_in: endpoint {
+				remote-endpoint = <&hdmi_out>;
+			};
+		};
+	};
+
 	cpus {
 		cpu0: cpu@0 {
 			cpu-supply = <&vdd_cpu>;
diff --git a/arch/arm/boot/dts/nvidia/tegra30-asus-tf600t.dts b/arch/arm/boot/dts/nvidia/tegra30-asus-tf600t.dts
index 1ed0536ae3fa..498780a96cf9 100644
--- a/arch/arm/boot/dts/nvidia/tegra30-asus-tf600t.dts
+++ b/arch/arm/boot/dts/nvidia/tegra30-asus-tf600t.dts
@@ -67,8 +67,11 @@ hdmi: hdmi@54280000 {
 			pll-supply = <&vdd_1v8_vio>;
 			vdd-supply = <&vdd_3v3_sys>;
 
-			nvidia,hpd-gpio = <&gpio TEGRA_GPIO(N, 7) GPIO_ACTIVE_HIGH>;
-			nvidia,ddc-i2c-bus = <&hdmi_ddc>;
+			port {
+				hdmi_out: endpoint {
+					remote-endpoint = <&connector_in>;
+				};
+			};
 		};
 
 		lcd: dsi@54300000 {
@@ -2302,6 +2305,20 @@ clk32k_in: clock-32k {
 		clock-output-names = "pmic-oscillator";
 	};
 
+	connector {
+		compatible = "hdmi-connector";
+		type = "d";
+
+		hpd-gpios = <&gpio TEGRA_GPIO(N, 7) GPIO_ACTIVE_HIGH>;
+		ddc-i2c-bus = <&hdmi_ddc>;
+
+		port {
+			connector_in: endpoint {
+				remote-endpoint = <&hdmi_out>;
+			};
+		};
+	};
+
 	cpus {
 		cpu0: cpu@0 {
 			cpu-supply = <&vdd_cpu>;
diff --git a/arch/arm/boot/dts/nvidia/tegra30-asus-transformer-common.dtsi b/arch/arm/boot/dts/nvidia/tegra30-asus-transformer-common.dtsi
index 53382e10f29f..0b0713d62e32 100644
--- a/arch/arm/boot/dts/nvidia/tegra30-asus-transformer-common.dtsi
+++ b/arch/arm/boot/dts/nvidia/tegra30-asus-transformer-common.dtsi
@@ -166,8 +166,11 @@ hdmi: hdmi@54280000 {
 			pll-supply = <&vdd_1v8_vio>;
 			vdd-supply = <&vdd_3v3_sys>;
 
-			nvidia,hpd-gpio = <&gpio TEGRA_GPIO(N, 7) GPIO_ACTIVE_HIGH>;
-			nvidia,ddc-i2c-bus = <&hdmi_ddc>;
+			port {
+				hdmi_out: endpoint {
+					remote-endpoint = <&connector_in>;
+				};
+			};
 		};
 	};
 
@@ -1713,6 +1716,20 @@ clk32k_in: clock-32k {
 		clock-output-names = "pmic-oscillator";
 	};
 
+	connector {
+		compatible = "hdmi-connector";
+		type = "d";
+
+		hpd-gpios = <&gpio TEGRA_GPIO(N, 7) GPIO_ACTIVE_HIGH>;
+		ddc-i2c-bus = <&hdmi_ddc>;
+
+		port {
+			connector_in: endpoint {
+				remote-endpoint = <&hdmi_out>;
+			};
+		};
+	};
+
 	cpus {
 		cpu0: cpu@0 {
 			cpu-supply = <&vdd_cpu>;
-- 
2.51.0

Re: [PATCH v1 1/2] dt-bindings: display: tegra: document Tegra20 HDMI port

[Rob Herring (Arm)]

On Tue, 10 Feb 2026 11:49:07 +0200, Svyatoslav Ryhel wrote:
> Tegra HDMI can be modeled using an OF graph. Reflect this in the bindings.
> 
> Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
> ---
>  .../bindings/display/tegra/nvidia,tegra20-hdmi.yaml | 13 +++++++++++--
>  1 file changed, 11 insertions(+), 2 deletions(-)
> 

My bot found errors running 'make dt_binding_check' on your patch:

yamllint warnings/errors:
./Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-hdmi.yaml:107:5: [warning] wrong indentation: expected 6 but found 4 (indentation)
./Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-hdmi.yaml:110:5: [warning] wrong indentation: expected 6 but found 4 (indentation)

dtschema/dtc warnings/errors:

doc reference errors (make refcheckdocs):

See https://patchwork.kernel.org/project/devicetree/patch/20260210094908.14276-2-clamor95@gmail.com

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.

Re: [PATCH v1 1/2] dt-bindings: display: tegra: document Tegra20 HDMI port

[Rob Herring]

On Tue, Feb 10, 2026 at 11:49:07AM +0200, Svyatoslav Ryhel wrote:
> Tegra HDMI can be modeled using an OF graph. Reflect this in the bindings.
> 
> Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
> ---
>  .../bindings/display/tegra/nvidia,tegra20-hdmi.yaml | 13 +++++++++++--
>  1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-hdmi.yaml b/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-hdmi.yaml
> index f77197e4869f..f33b700bf0ee 100644
> --- a/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-hdmi.yaml
> +++ b/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-hdmi.yaml
> @@ -82,6 +82,10 @@ properties:
>      description: phandle of a display panel
>      $ref: /schemas/types.yaml#/definitions/phandle
>  
> +  port:
> +    description: connection to controller receiving HDMI signals

Describe this in terms of this block, not what it is connected to. It 
could be an hdmi-connector node or a bridge.

> +    $ref: /schemas/graph.yaml#/properties/port
> +
>    "#sound-dai-cells":
>      const: 0
>  
> @@ -97,8 +101,13 @@ required:
>    - reset-names
>    - pll-supply
>    - vdd-supply
> -  - nvidia,ddc-i2c-bus
> -  - nvidia,hpd-gpio
> +
> +anyOf:
> +  - required:
> +    - nvidia,ddc-i2c-bus
> +    - nvidia,hpd-gpio
> +  - required:
> +    - port
>  
>  examples:
>    - |
> -- 
> 2.51.0
> 

Re: [PATCH v1 1/2] dt-bindings: display: tegra: document Tegra20 HDMI port

[Svyatoslav Ryhel]

10 лютого 2026 р. 16:19:17 GMT+02:00, Rob Herring <robh@kernel.org> пише:
>On Tue, Feb 10, 2026 at 11:49:07AM +0200, Svyatoslav Ryhel wrote:
>> Tegra HDMI can be modeled using an OF graph. Reflect this in the bindings.
>> 
>> Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
>> ---
>>  .../bindings/display/tegra/nvidia,tegra20-hdmi.yaml | 13 +++++++++++--
>>  1 file changed, 11 insertions(+), 2 deletions(-)
>> 
>> diff --git a/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-hdmi.yaml b/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-hdmi.yaml
>> index f77197e4869f..f33b700bf0ee 100644
>> --- a/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-hdmi.yaml
>> +++ b/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-hdmi.yaml
>> @@ -82,6 +82,10 @@ properties:
>>      description: phandle of a display panel
>>      $ref: /schemas/types.yaml#/definitions/phandle
>>  
>> +  port:
>> +    description: connection to controller receiving HDMI signals
>
>Describe this in terms of this block, not what it is connected to. It 
>could be an hdmi-connector node or a bridge.
>

Isn't the idea of port to provide connection to the remove device. How should I word it: "links HDMI host with the receiver" or "output of HDMI"? I don't quite understand what you mean. Maybe I should remove description entirely, HDMI has a single port and its function is pretty strait forward.

>> +    $ref: /schemas/graph.yaml#/properties/port
>> +
>>    "#sound-dai-cells":
>>      const: 0
>>  
>> @@ -97,8 +101,13 @@ required:
>>    - reset-names
>>    - pll-supply
>>    - vdd-supply
>> -  - nvidia,ddc-i2c-bus
>> -  - nvidia,hpd-gpio
>> +
>> +anyOf:
>> +  - required:
>> +    - nvidia,ddc-i2c-bus
>> +    - nvidia,hpd-gpio
>> +  - required:
>> +    - port
>>  
>>  examples:
>>    - |
>> -- 
>> 2.51.0
>> 

Claude review: ARM: tegra: document Tegra20 HDMI port

[Claude Code Review Bot]

Overall Series Review

Subject: ARM: tegra: document Tegra20 HDMI port
Author: Svyatoslav Ryhel <clamor95@gmail.com>
Patches: 5
Reviewed: 2026-02-11T16:27:52.817707

---

This 2-patch series adds OF graph support to the Tegra20/30 HDMI bindings and migrates ASUS Transformer devices to use the connector framework. The series has one critical issue that blocks merging:

**BLOCKING ISSUES:**
1. **YAML indentation errors** in patch 1/2 - The dt-binding bot found yamllint warnings about incorrect indentation (lines 107, 110). This must be fixed before the binding can be accepted.

**TECHNICAL ASSESSMENT:**
- The approach is sound: moving from deprecated `nvidia,ddc-i2c-bus` and `nvidia,hpd-gpio` properties to the modern OF graph + connector framework pattern
- The binding change correctly makes the properties mutually exclusive via `anyOf`
- DTS changes are mechanical and consistent across all three device trees
- Testing coverage is good with Tested-by tags from multiple devices

**FEEDBACK FROM MAINTAINERS:**
- Rob Herring's automated bot caught the indentation issue
- Rob Herring requested a clarification on the port description (should describe the block itself, not what it connects to)

**RECOMMENDATION:** Fix the indentation and description issues in v2, then the series should be ready for merge.

---

---
Generated by Claude Code Patch Reviewer

Claude review: dt-bindings: display: tegra: document Tegra20 HDMI port

[Claude Code Review Bot]

Patch Review

**COMMIT MESSAGE:**
The commit message is minimal but adequate for a binding addition. It states what is being added without explaining why the change is needed.

**TECHNICAL ISSUES:**

1. **YAML indentation errors (BLOCKING):**
```yaml
+anyOf:
+  - required:
+    - nvidia,ddc-i2c-bus
+    - nvidia,hpd-gpio
+  - required:
+    - port
```

The yamllint warnings indicate lines 107 and 110 have incorrect indentation. The `- required:` entries under `anyOf` should be indented with 6 spaces, not 4. This causes the binding validation to fail.

**Correct format should be:**
```yaml
anyOf:
  - required:
      - nvidia,ddc-i2c-bus
      - nvidia,hpd-gpio
  - required:
      - port
```

2. **Port description clarity:**
```yaml
+  port:
+    description: connection to controller receiving HDMI signals
```

Rob Herring correctly points out this describes the remote endpoint, not the local port. The description should focus on what this HDMI block outputs.

**Suggested improvement:**
```yaml
  port:
    description: HDMI output port for connection to HDMI connector or bridge
```

**STRUCTURAL REVIEW:**

The logic of making `nvidia,ddc-i2c-bus`/`nvidia,hpd-gpio` and `port` mutually exclusive via `anyOf` is correct:
- Old binding: direct DDC/HPD properties (deprecated but still supported)
- New binding: OF graph port (connects to hdmi-connector node)

This maintains backward compatibility while enabling the modern approach.

**RATING:** Needs work (indentation must be fixed, description should be improved)

---

---
Generated by Claude Code Patch Reviewer

Claude review: ARM: tegra: transformers: add connector node

[Claude Code Review Bot]

Patch Review

**COMMIT MESSAGE:**
Clear and well-written. Explains what hardware is present, why the change is being made (bridge/connector support), and includes excellent testing coverage with Tested-by tags from three different devices.

**TECHNICAL REVIEW:**

The changes are consistent and correct across all three files. Each follows the same pattern:

**Pattern applied in tegra20-asus-transformer-common.dtsi (lines 369-400):**
```diff
-		nvidia,ddc-i2c-bus = <&hdmi_ddc>;
-		nvidia,hpd-gpio = <&gpio TEGRA_GPIO(N, 7)
-			GPIO_ACTIVE_HIGH>;
+		port {
+			hdmi_out: endpoint {
+				remote-endpoint = <&connector_in>;
+			};
+		};
```

And the corresponding connector node:
```diff
+	connector {
+		compatible = "hdmi-connector";
+		type = "d";
+
+		hpd-gpios = <&gpio TEGRA_GPIO(N, 7) GPIO_ACTIVE_HIGH>;
+		ddc-i2c-bus = <&hdmi_ddc>;
+
+		port {
+			connector_in: endpoint {
+				remote-endpoint = <&hdmi_out>;
+			};
+		};
+	};
```

**CORRECTNESS CHECKS:**

1. **Connector type:** `type = "d"` is correct for micro-HDMI (Type D) connectors as stated in the commit message
2. **GPIO polarity:** `GPIO_ACTIVE_HIGH` is preserved from the original binding
3. **DDC bus reference:** `<&hdmi_ddc>` correctly preserved
4. **OF graph connections:** The remote-endpoint references are bidirectional and correct
5. **Node placement:** Connector nodes are correctly placed at the root level (not under any bus)

**CONSISTENCY:**
The exact same transformation is applied to:
- `arch/arm/boot/dts/nvidia/tegra20-asus-transformer-common.dtsi`
- `arch/arm/boot/dts/nvidia/tegra30-asus-tf600t.dts`
- `arch/arm/boot/dts/nvidia/tegra30-asus-transformer-common.dtsi`

All three use the same GPIO (`TEGRA_GPIO(N, 7)`), same connector type (`"d"`), and same reference name (`hdmi_ddc`), which makes sense as these are all ASUS Transformer variant devices.

**POTENTIAL CONCERNS:**

None identified. The mechanical transformation is straightforward and the testing coverage confirms it works on real hardware.

**DEPENDENCIES:**

This patch depends on:
1. Patch 1/2 being accepted (binding must allow the `port` property)
2. The kernel having hdmi-connector driver support (already upstream)
3. The Tegra HDMI driver having bridge/connector support (mentioned in commit message as already done)

**RATING:** Ready for merge (contingent on patch 1/2 being fixed and merged first)

---

**SUMMARY:**
- Patch 1/2: **Needs revision** (fix indentation, improve description)
- Patch 2/2: **Ready** (well-tested, correct implementation)
- Series approach: **Sound** (proper migration to modern connector framework)

---
Generated by Claude Code Patch Reviewer