[PATCH 05/40] arm64: dts: rockchip: Add frl-enable-gpios to rk3576-luckfox-core3576

Cristian Ciocaltea
2026-04-17T09:25:40Z

The board exposes the GPIO4_C6 line to control the voltage bias on the
HDMI data lines. It must be asserted when operating in HDMI 2.1 FRL
mode and deasserted for HDMI 1.4/2.0 TMDS mode.

Wire up the HDMI node to the GPIO line using the frl-enable-gpios
property and drop the line from the vcc_5v0_hdmi regulator to allow
adjusting the bias when transitioning between TMDS and FRL operating
modes.

Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
---
arch/arm64/boot/dts/rockchip/rk3576-luckfox-core3576.dtsi | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/boot/dts/rockchip/rk3576-luckfox-core3576.dtsi b/arch/arm64/boot/dts/rockchip/rk3576-luckfox-core3576.dtsi
index 749f0a54b478..93ae37699366 100644
--- a/arch/arm64/boot/dts/rockchip/rk3576-luckfox-core3576.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3576-luckfox-core3576.dtsi
@@ -140,10 +140,7 @@ regulator-state-mem {

vcc_5v0_hdmi: regulator-vcc-5v0-hdmi {
compatible = "regulator-fixed";
- enable-active-high;
- gpios = <&gpio4 RK_PC6 GPIO_ACTIVE_HIGH>;
- pinctrl-names = "default";
- pinctrl-0 = <&hdmi_con_en>;
+ regulator-always-on;
regulator-min-microvolt = <5000000>;
regulator-max-microvolt = <5000000>;
regulator-name = "vcc_5v0_hdmi";
@@ -231,6 +228,8 @@ &gpu {
};

&hdmi {
+ pinctrl-0 = <&hdmi_txm0_pins &hdmi_tx_scl &hdmi_tx_sda &hdmi_frl_en>;
+ frl-enable-gpios = <&gpio4 RK_PC6 GPIO_ACTIVE_LOW>;
status = "okay";
};

@@ -655,7 +654,7 @@ &pcie0 {

&pinctrl {
hdmi {
- hdmi_con_en: hdmi-con-en {
+ hdmi_frl_en: hdmi-frl-en {
rockchip,pins = <4 RK_PC6 RK_FUNC_GPIO &pcfg_pull_none>;