[PATCH 0/3] Add VGA support for Apalis iMX6

[PATCH 0/3] Add VGA support for Apalis iMX6

[Leonardo Costa]

This series adds a device tree overlay that enables the VGA output on Apalis
iMX6, which is driven from a parallel RGB interface passing through a
non-programmable video DAC.

The video DAC is a simple resistor network gated by an active-low
data-enable signal. For the bridge to work properly, this series also
changes the following in the dt-bindings and simple-bridge driver:

- dt-bindings: Add a new compatible for the bridge in the simple-bridge
  binding. This is necessary because the existing dumb-vga-dac compatible
  doesn't describe a data-enable signal polarity.

- simple-bridge: Add the VGA bridge match-table entry and timings
  struct, setting the DRM_BUS_FLAG_DE_LOW flag for the bridge.

This change depends on another patch, and should be applied after it:

- https://lore.kernel.org/all/20261002-v1-simple-bridge-atomic-check-v1-1-ef5d8332b078@toradex.com/T/#u

  Adds the atomic_check function to the simple-bridge driver, which
  allows the data-enable bus flag to be propagated through the DRM
  pipeline. This is necessary for the VGA to work correctly on the
  Apalis iMX6.

Signed-off-by: Leonardo Costa <leonardo.costa@toradex.com>
---
Leonardo Costa (3):
      dt-bindings: display: bridge: simple: Add the Toradex Apalis iMX6 VGA DAC bridge
      drm/bridge: simple-bridge: Add Toradex RGB to VGA DAC bridge
      ARM: dts: imx6q-apalis: Add VGA overlay

 .../bindings/display/bridge/simple-bridge.yaml     |  1 +
 arch/arm/boot/dts/nxp/imx/Makefile                 | 21 ++++++
 .../boot/dts/nxp/imx/imx6q-apalis-eval-vga.dtso    | 79 ++++++++++++++++++++++
 drivers/gpu/drm/bridge/simple-bridge.c             | 10 +++
 4 files changed, 111 insertions(+)
---
base-commit: f5f84daefcd92d7a630066635ecea1433ed5eac7
change-id: 20260928-v1-apalis-imx6-enable-vga-5c7ba6b358fe

Best regards,
-- 
Leonardo Costa <leonardo.costa@toradex.com>

[PATCH 1/3] dt-bindings: display: bridge: simple: Add the Toradex Apalis iMX6 VGA DAC bridge

[Leonardo Costa]

From: Leonardo Costa <leonardo.costa@toradex.com>

The VGA bridge on Apalis iMX6 consists of a simple resistor ladder that
converts a digital 16-bit RGB signal to VGA. The VGA output is gated by
an active-low data-enable signal.

Add a dedicated compatible for the bridge, since the generic
dumb-vga-dac doesn't describe a data-enable signal.

Signed-off-by: Leonardo Costa <leonardo.costa@toradex.com>
---
 Documentation/devicetree/bindings/display/bridge/simple-bridge.yaml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/display/bridge/simple-bridge.yaml b/Documentation/devicetree/bindings/display/bridge/simple-bridge.yaml
index 7636c24906ba..a86231a4a908 100644
--- a/Documentation/devicetree/bindings/display/bridge/simple-bridge.yaml
+++ b/Documentation/devicetree/bindings/display/bridge/simple-bridge.yaml
@@ -37,6 +37,7 @@ properties:
           - ti,opa362
           - ti,ths8134
           - ti,ths8135
+          - toradex,apalis-imx6-vga-dac
 
   ports:
     $ref: /schemas/graph.yaml#/properties/ports

-- 
2.43.0

[PATCH 2/3] drm/bridge: simple-bridge: Add Toradex RGB to VGA DAC bridge

[Leonardo Costa]

From: Leonardo Costa <leonardo.costa@toradex.com>

The VGA bridge on Apalis iMX6 consists of a simple resistor ladder that
converts a digital 16-bit RGB signal to VGA. The VGA output is gated by
an active-low data-enable signal.

Signed-off-by: Leonardo Costa <leonardo.costa@toradex.com>
---
 drivers/gpu/drm/bridge/simple-bridge.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/gpu/drm/bridge/simple-bridge.c b/drivers/gpu/drm/bridge/simple-bridge.c
index 3fba7002322e..3f88fcdfa214 100644
--- a/drivers/gpu/drm/bridge/simple-bridge.c
+++ b/drivers/gpu/drm/bridge/simple-bridge.c
@@ -253,6 +253,10 @@ static const struct drm_bridge_timings ti_ths8135_bridge_timings = {
 	.hold_time_ps = 500,
 };
 
+static const struct drm_bridge_timings toradex_apalis_imx6_vga_dac_timings = {
+	.input_bus_flags = DRM_BUS_FLAG_DE_LOW,
+};
+
 static const struct of_device_id simple_bridge_match[] = {
 	{
 		.compatible = "dumb-vga-dac",
@@ -312,6 +316,12 @@ static const struct of_device_id simple_bridge_match[] = {
 			.timings = &ti_ths8134_bridge_timings,
 			.connector_type = DRM_MODE_CONNECTOR_VGA,
 		},
+	}, {
+		.compatible = "toradex,apalis-imx6-vga-dac",
+		.data = &(const struct simple_bridge_info) {
+			.timings = &toradex_apalis_imx6_vga_dac_timings,
+			.connector_type = DRM_MODE_CONNECTOR_VGA,
+		},
 	},
 	{},
 };

-- 
2.43.0

[PATCH 3/3] ARM: dts: imx6q-apalis: Add VGA overlay

[Leonardo Costa]

From: Leonardo Costa <leonardo.costa@toradex.com>

Add a device tree overlay for the VGA output available on the Apalis
Evaluation Board, which is driven from a parallel RGB interface passing
through a non-programmable video DAC to a VGA connector, without VESA
DDC I2C signals.

The overlay is also combined with the various Apalis Evaluation Board
device trees to provide ready-to-use DTBs.

Signed-off-by: Leonardo Costa <leonardo.costa@toradex.com>
---
 arch/arm/boot/dts/nxp/imx/Makefile                 | 21 ++++++
 .../boot/dts/nxp/imx/imx6q-apalis-eval-vga.dtso    | 79 ++++++++++++++++++++++
 2 files changed, 100 insertions(+)

diff --git a/arch/arm/boot/dts/nxp/imx/Makefile b/arch/arm/boot/dts/nxp/imx/Makefile
index c5caca92ea10..b5ad9172e1f4 100644
--- a/arch/arm/boot/dts/nxp/imx/Makefile
+++ b/arch/arm/boot/dts/nxp/imx/Makefile
@@ -59,6 +59,22 @@ dtb-$(CONFIG_SOC_IMX53) += \
 imx53-qsb-hdmi-dtbs := imx53-qsb.dtb imx53-qsb-hdmi.dtbo
 imx53-qsrb-hdmi-dtbs := imx53-qsrb.dtb imx53-qsb-hdmi.dtbo
 
+imx6q-apalis-eval-v1.2-vga-dtbs := \
+	imx6q-apalis-eval-v1.2.dtb \
+	imx6q-apalis-eval-vga.dtbo
+
+imx6q-apalis-eval-vga-dtbs := \
+	imx6q-apalis-eval.dtb \
+	imx6q-apalis-eval-vga.dtbo
+
+imx6q-apalis-v1.2-eval-v1.2-vga-dtbs := \
+	imx6q-apalis-v1.2-eval-v1.2.dtb \
+	imx6q-apalis-eval-vga.dtbo
+
+imx6q-apalis-v1.2-eval-vga-dtbs := \
+	imx6q-apalis-v1.2-eval.dtb \
+	imx6q-apalis-eval-vga.dtbo
+
 imx6qdl-dhcom-pdk2-overlay-497-200-x12-dtbs := \
 	imx6q-dhcom-pdk2.dtb \
 	imx6qdl-dhcom-pdk2-overlay-497-200-x12.dtbo
@@ -184,11 +200,16 @@ dtb-$(CONFIG_SOC_IMX6Q) += \
 	imx6dl-yapp4-ursa.dtb \
 	imx6q-apalis-eval.dtb \
 	imx6q-apalis-eval-v1.2.dtb \
+	imx6q-apalis-eval-v1.2-vga.dtb \
+	imx6q-apalis-eval-vga.dtb \
+	imx6q-apalis-eval-vga.dtbo \
 	imx6q-apalis-ixora.dtb \
 	imx6q-apalis-ixora-v1.1.dtb \
 	imx6q-apalis-ixora-v1.2.dtb \
 	imx6q-apalis-v1.2-eval.dtb \
 	imx6q-apalis-v1.2-eval-v1.2.dtb \
+	imx6q-apalis-v1.2-eval-v1.2-vga.dtb \
+	imx6q-apalis-v1.2-eval-vga.dtb \
 	imx6q-apalis-v1.2-ixora.dtb \
 	imx6q-apalis-v1.2-ixora-v1.1.dtb \
 	imx6q-apalis-v1.2-ixora-v1.2.dtb \
diff --git a/arch/arm/boot/dts/nxp/imx/imx6q-apalis-eval-vga.dtso b/arch/arm/boot/dts/nxp/imx/imx6q-apalis-eval-vga.dtso
new file mode 100644
index 000000000000..a449ef9fbfaf
--- /dev/null
+++ b/arch/arm/boot/dts/nxp/imx/imx6q-apalis-eval-vga.dtso
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0-only OR MIT
+/*
+ * Copyright (c) Toradex
+ *
+ * VGA output connected to a parallel RGB LCD interface through a
+ * non-programmable video DAC with a VGA connector.
+ *
+ * The VGA output is available on the Apalis Evaluation Board without VESA DDC
+ * I2C signals.
+ */
+
+/dts-v1/;
+/plugin/;
+
+&{/} {
+	disp1 {
+		compatible = "fsl,imx-parallel-display";
+		pinctrl-names = "default";
+		pinctrl-0 = <&pinctrl_ipu2_vdac>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		interface-pix-fmt = "rgb565";
+
+		port@0 {
+			reg = <0>;
+
+			vga_display_in: endpoint {
+				remote-endpoint = <&ipu2_di0_disp0>;
+			};
+		};
+
+		port@1 {
+			reg = <1>;
+
+			vga_display_out: endpoint {
+				remote-endpoint = <&vga_enc_in>;
+			};
+		};
+	};
+
+	vga-encoder {
+		compatible = "toradex,apalis-imx6-vga-dac";
+
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port@0 {
+				reg = <0>;
+
+				vga_enc_in: endpoint {
+					remote-endpoint = <&vga_display_out>;
+				};
+			};
+
+			port@1 {
+				reg = <1>;
+
+				vga_enc_out: endpoint {
+					remote-endpoint = <&vga_connector_in>;
+				};
+			};
+		};
+	};
+
+	vga-connector {
+		compatible = "vga-connector";
+
+		port {
+			vga_connector_in: endpoint {
+				remote-endpoint = <&vga_enc_out>;
+			};
+		};
+	};
+};
+
+&ipu2_di0_disp0 {
+	remote-endpoint = <&vga_display_in>;
+};

-- 
2.43.0

Re: [PATCH 1/3] dt-bindings: display: bridge: simple: Add the Toradex Apalis iMX6 VGA DAC bridge

[Frank Li]

On Mon, Oct 12, 2026 at 04:25:23AM -0300, Leonardo Costa wrote:
> From: Leonardo Costa <leonardo.costa@toradex.com>
>
> The VGA bridge on Apalis iMX6 consists of a simple resistor ladder that
> converts a digital 16-bit RGB signal to VGA. The VGA output is gated by
> an active-low data-enable signal.
>
> Add a dedicated compatible for the bridge, since the generic
> dumb-vga-dac doesn't describe a data-enable signal.
>
> Signed-off-by: Leonardo Costa <leonardo.costa@toradex.com>
> ---

Reviewed-by: Frank Li <Frank.Li@nxp.com>

>  Documentation/devicetree/bindings/display/bridge/simple-bridge.yaml | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/Documentation/devicetree/bindings/display/bridge/simple-bridge.yaml b/Documentation/devicetree/bindings/display/bridge/simple-bridge.yaml
> index 7636c24906ba..a86231a4a908 100644
> --- a/Documentation/devicetree/bindings/display/bridge/simple-bridge.yaml
> +++ b/Documentation/devicetree/bindings/display/bridge/simple-bridge.yaml
> @@ -37,6 +37,7 @@ properties:
>            - ti,opa362
>            - ti,ths8134
>            - ti,ths8135
> +          - toradex,apalis-imx6-vga-dac
>
>    ports:
>      $ref: /schemas/graph.yaml#/properties/ports
>
> --
> 2.43.0
>
>

Re: [PATCH 2/3] drm/bridge: simple-bridge: Add Toradex RGB to VGA DAC bridge

[Frank Li]

On Mon, Oct 12, 2026 at 04:25:24AM -0300, Leonardo Costa wrote:
> From: Leonardo Costa <leonardo.costa@toradex.com>
>
> The VGA bridge on Apalis iMX6 consists of a simple resistor ladder that
> converts a digital 16-bit RGB signal to VGA. The VGA output is gated by
> an active-low data-enable signal.
>
> Signed-off-by: Leonardo Costa <leonardo.costa@toradex.com>
> ---

Reviewed-by: Frank Li <Frank.Li@nxp.com>

>  drivers/gpu/drm/bridge/simple-bridge.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
>
> diff --git a/drivers/gpu/drm/bridge/simple-bridge.c b/drivers/gpu/drm/bridge/simple-bridge.c
> index 3fba7002322e..3f88fcdfa214 100644
> --- a/drivers/gpu/drm/bridge/simple-bridge.c
> +++ b/drivers/gpu/drm/bridge/simple-bridge.c
> @@ -253,6 +253,10 @@ static const struct drm_bridge_timings ti_ths8135_bridge_timings = {
>  	.hold_time_ps = 500,
>  };
>
> +static const struct drm_bridge_timings toradex_apalis_imx6_vga_dac_timings = {
> +	.input_bus_flags = DRM_BUS_FLAG_DE_LOW,
> +};
> +
>  static const struct of_device_id simple_bridge_match[] = {
>  	{
>  		.compatible = "dumb-vga-dac",
> @@ -312,6 +316,12 @@ static const struct of_device_id simple_bridge_match[] = {
>  			.timings = &ti_ths8134_bridge_timings,
>  			.connector_type = DRM_MODE_CONNECTOR_VGA,
>  		},
> +	}, {
> +		.compatible = "toradex,apalis-imx6-vga-dac",
> +		.data = &(const struct simple_bridge_info) {
> +			.timings = &toradex_apalis_imx6_vga_dac_timings,
> +			.connector_type = DRM_MODE_CONNECTOR_VGA,
> +		},
>  	},
>  	{},
>  };
>
> --
> 2.43.0
>
>

Re: [PATCH 3/3] ARM: dts: imx6q-apalis: Add VGA overlay

[Frank Li]

On Mon, Oct 12, 2026 at 04:25:25AM -0300, Leonardo Costa wrote:
> From: Leonardo Costa <leonardo.costa@toradex.com>
>
> Add a device tree overlay for the VGA output available on the Apalis
> Evaluation Board, which is driven from a parallel RGB interface passing
> through a non-programmable video DAC to a VGA connector, without VESA
> DDC I2C signals.
>
> The overlay is also combined with the various Apalis Evaluation Board
> device trees to provide ready-to-use DTBs.
>
> Signed-off-by: Leonardo Costa <leonardo.costa@toradex.com>
> ---
>  arch/arm/boot/dts/nxp/imx/Makefile                 | 21 ++++++
>  .../boot/dts/nxp/imx/imx6q-apalis-eval-vga.dtso    | 79 ++++++++++++++++++++++
>  2 files changed, 100 insertions(+)
>
> diff --git a/arch/arm/boot/dts/nxp/imx/Makefile b/arch/arm/boot/dts/nxp/imx/Makefile
> index c5caca92ea10..b5ad9172e1f4 100644
> --- a/arch/arm/boot/dts/nxp/imx/Makefile
> +++ b/arch/arm/boot/dts/nxp/imx/Makefile
> @@ -59,6 +59,22 @@ dtb-$(CONFIG_SOC_IMX53) += \
>  imx53-qsb-hdmi-dtbs := imx53-qsb.dtb imx53-qsb-hdmi.dtbo
>  imx53-qsrb-hdmi-dtbs := imx53-qsrb.dtb imx53-qsb-hdmi.dtbo
>
> +imx6q-apalis-eval-v1.2-vga-dtbs := \
> +	imx6q-apalis-eval-v1.2.dtb \
> +	imx6q-apalis-eval-vga.dtbo
> +
> +imx6q-apalis-eval-vga-dtbs := \
> +	imx6q-apalis-eval.dtb \
> +	imx6q-apalis-eval-vga.dtbo
> +
> +imx6q-apalis-v1.2-eval-v1.2-vga-dtbs := \
> +	imx6q-apalis-v1.2-eval-v1.2.dtb \
> +	imx6q-apalis-eval-vga.dtbo
> +
> +imx6q-apalis-v1.2-eval-vga-dtbs := \
> +	imx6q-apalis-v1.2-eval.dtb \
> +	imx6q-apalis-eval-vga.dtbo
> +

Thank you using one overlay cover difference boards

Frank

Re: [PATCH 0/3] Add VGA support for Apalis iMX6

[Laurent Pinchart]

On Mon, Oct 12, 2026 at 04:25:22AM -0300, Leonardo Costa wrote:
> This series adds a device tree overlay that enables the VGA output on Apalis
> iMX6, which is driven from a parallel RGB interface passing through a
> non-programmable video DAC.
> 
> The video DAC is a simple resistor network gated by an active-low
> data-enable signal. For the bridge to work properly, this series also
> changes the following in the dt-bindings and simple-bridge driver:
> 
> - dt-bindings: Add a new compatible for the bridge in the simple-bridge
>   binding. This is necessary because the existing dumb-vga-dac compatible
>   doesn't describe a data-enable signal polarity.
> 
> - simple-bridge: Add the VGA bridge match-table entry and timings
>   struct, setting the DRM_BUS_FLAG_DE_LOW flag for the bridge.

Is there schematics available anywhere ? That would help reviewing the
series ?

> 
> This change depends on another patch, and should be applied after it:
> 
> - https://lore.kernel.org/all/20261002-v1-simple-bridge-atomic-check-v1-1-ef5d8332b078@toradex.com/T/#u
> 
>   Adds the atomic_check function to the simple-bridge driver, which
>   allows the data-enable bus flag to be propagated through the DRM
>   pipeline. This is necessary for the VGA to work correctly on the
>   Apalis iMX6.
> 
> Signed-off-by: Leonardo Costa <leonardo.costa@toradex.com>
> ---
> Leonardo Costa (3):
>       dt-bindings: display: bridge: simple: Add the Toradex Apalis iMX6 VGA DAC bridge
>       drm/bridge: simple-bridge: Add Toradex RGB to VGA DAC bridge
>       ARM: dts: imx6q-apalis: Add VGA overlay
> 
>  .../bindings/display/bridge/simple-bridge.yaml     |  1 +
>  arch/arm/boot/dts/nxp/imx/Makefile                 | 21 ++++++
>  .../boot/dts/nxp/imx/imx6q-apalis-eval-vga.dtso    | 79 ++++++++++++++++++++++
>  drivers/gpu/drm/bridge/simple-bridge.c             | 10 +++
>  4 files changed, 111 insertions(+)
> ---
> base-commit: f5f84daefcd92d7a630066635ecea1433ed5eac7
> change-id: 20260928-v1-apalis-imx6-enable-vga-5c7ba6b358fe

-- 
Regards,

Laurent Pinchart

Re: [PATCH 1/3] dt-bindings: display: bridge: simple: Add the Toradex Apalis iMX6 VGA DAC bridge

[Conor Dooley]

[-- Attachment #1: Type: text/plain, Size: 75 bytes --]

Acked-by: Conor Dooley <conor.dooley@microchip.com>
pw-bot: not-applicable

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]