From: Frieder Schrempf <frieder.schrempf@kontron.de>

The GPIO that controls the power supply for the LVDS display
connector has changed between early prototypes and the current
production design of the hardware. Reflect this change in the
devicetree to properly switch on the panel supply.

This was working before even with the wrong GPIO due to the
bidirectional level shifter used on the board which drives the EN
signal high even when the input has a (weak) pull down configured as
reset condition of the SoC pad. As a result the display was working
but the supply was always on.

Tested on BL i.MX8MP to show the correct voltage level on the level
shifter input.

Fixes: 946ab10e3f40 ("arm64: dts: Add support for Kontron OSM-S i.MX8MP SoM and BL carrier board")
Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
---
 .../boot/dts/freescale/imx8mp-kontron-bl-osm-s.dts   | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/freescale/imx8mp-kontron-bl-osm-s.dts b/arch/arm64/boot/dts/freescale/imx8mp-kontron-bl-osm-s.dts
index 75ae46642782..29ce863403b8 100644
--- a/arch/arm64/boot/dts/freescale/imx8mp-kontron-bl-osm-s.dts
+++ b/arch/arm64/boot/dts/freescale/imx8mp-kontron-bl-osm-s.dts
@@ -49,7 +49,9 @@ pwm-beeper {
 
 	reg_vcc_panel: regulator-vcc-panel {
 		compatible = "regulator-fixed";
-		gpio = <&gpio4 3 GPIO_ACTIVE_HIGH>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&pinctrl_reg_vcc_panel>;
+		gpio = <&gpio5 3 GPIO_ACTIVE_HIGH>;
 		enable-active-high;
 		regulator-max-microvolt = <3300000>;
 		regulator-min-microvolt = <3300000>;
@@ -172,7 +174,7 @@ &gpio4 {
 &gpio5 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_gpio5>;
-	gpio-line-names = "I2S_BITCLK", "I2S_A_DATA_OUT", "I2S_MCLK", "PWM_2",
+	gpio-line-names = "I2S_BITCLK", "I2S_A_DATA_OUT", "I2S_MCLK", "VCC_PANEL_EN",
 			  "PWM_1", "PWM_0", "SPI_A_SCK", "CAN_ADDR1",
 			  "CAN_ADDR0", "SPI_A_CS0", "SPI_B_SCK", "SPI_B_SDO",
 			  "SPI_B_SDI", "SPI_B_CS0", "I2C_A_SCL", "I2C_A_SDA",
@@ -329,4 +331,10 @@ MX8MP_IOMUXC_ECSPI1_MOSI__GPIO5_IO07		0x46 /* CAN_ADR0 */
 			MX8MP_IOMUXC_ECSPI1_MISO__GPIO5_IO08		0x46 /* CAN_ADR1 */
 		>;
 	};
+
+	pinctrl_reg_vcc_panel: regvccpanelgrp {
+		fsl,pins = <
+			MX8MP_IOMUXC_SPDIF_TX__GPIO5_IO03		0x46
+		>;
+	};
 };
-- 
2.54.0

From: Frank Li <Frank.Li@nxp.com>


On Thu, 28 May 2026 12:15:56 +0200, Frieder Schrempf wrote:
> The GPIO that controls the power supply for the LVDS display
> connector has changed between early prototypes and the current
> production design of the hardware. Reflect this change in the
> devicetree to properly switch on the panel supply.
> 
> This was working before even with the wrong GPIO due to the
> bidirectional level shifter used on the board which drives the EN
> signal high even when the input has a (weak) pull down configured as
> reset condition of the SoC pad. As a result the display was working
> but the supply was always on.
> 
> [...]

Applied, thanks!

[1/1] arm64: dts: imx8mp-kontron: Fix GPIO for display power switch
      commit: ef64f97227a44177d68206cb88a9015897e34571

Best regards,
-- 
Frank Li <Frank.Li@nxp.com>