[PATCH 07/40] arm64: dts: rockchip: Add frl-enable-gpios to rk3576-nanopi-r76s

Cristian Ciocaltea
2026-04-17T09:25:48Z

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 vcc5v_hdmi_tx 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-nanopi-r76s.dts | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/boot/dts/rockchip/rk3576-nanopi-r76s.dts b/arch/arm64/boot/dts/rockchip/rk3576-nanopi-r76s.dts
index 7ec27b05ff10..21ef369c478c 100644
--- a/arch/arm64/boot/dts/rockchip/rk3576-nanopi-r76s.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3576-nanopi-r76s.dts
@@ -111,10 +111,7 @@ vcc5v_dcin: regulator-vcc5v-dcin {

vcc5v_hdmi_tx: regulator-vcc5v-hdmi-tx {
compatible = "regulator-fixed";
- enable-active-high;
- gpios = <&gpio4 RK_PC6 GPIO_ACTIVE_HIGH>;
- pinctrl-names = "default";
- pinctrl-0 = <&hdmi_tx_on_h>;
+ regulator-always-on;
regulator-min-microvolt = <5000000>;
regulator-max-microvolt = <5000000>;
regulator-name = "vcc5v_hdmi_tx";
@@ -252,6 +249,8 @@ &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";
};

@@ -717,7 +716,7 @@ led2_h: led2-h {
};

hdmi {
- hdmi_tx_on_h: hdmi-tx-on-h {
+ hdmi_frl_en: hdmi-frl-en {
rockchip,pins = <4 RK_PC6 RK_FUNC_GPIO &pcfg_pull_none>;
};
};

--
2.53.0