Re: [PATCH 3/5] arm64: dts: mediatek: cherry: Configure eDP and internal display

From: Chen-Yu Tsai
Date: Fri Apr 21 2023 - 02:57:44 EST


On Thu, Apr 20, 2023 at 5:45 PM AngeloGioacchino Del Regno
<angelogioacchino.delregno@xxxxxxxxxxxxx> wrote:
>
> Add the required nodes to enable the DisplayPort interface, connected
> to the Embedded DisplayPort port, where we have an internal display.
>
> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
> ---
> .../boot/dts/mediatek/mt8195-cherry.dtsi | 32 +++++++++++++++++++
> 1 file changed, 32 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi b/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi
> index 918380697a9a..46f1c8091498 100644
> --- a/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi
> +++ b/arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi
> @@ -49,6 +49,18 @@ memory@40000000 {
> reg = <0 0x40000000 0 0x80000000>;
> };
>
> + pp3300_disp_x: regulator-pp3300-disp-x {
> + compatible = "regulator-fixed";
> + regulator-name = "pp3300_disp_x";
> + regulator-min-microvolt = <3300000>;
> + regulator-max-microvolt = <3300000>;

>From the schematics:
vin-supply = <&pp3300_z2>;

Also, this is an RT9742. The datasheet says the typical enable time is
2.1ms. For a bit of margin, I'd say we could model it as 2.5ms? So:

regulator-enable-ramp-delay = <2500>;

ChenYu

> + enable-active-high;
> + gpio = <&pio 55 GPIO_ACTIVE_HIGH>;
> + pinctrl-names = "default";
> + pinctrl-0 = <&panel_fixed_pins>;
> + regulator-always-on;
> + };
> +
> /* system wide LDO 3.3V power rail */
> pp3300_z5: regulator-pp3300-ldo-z5 {
> compatible = "regulator-fixed";
> @@ -290,6 +302,20 @@ port@1 {
> reg = <1>;
> edp_out: endpoint {
> data-lanes = <0 1 2 3>;
> + remote-endpoint = <&panel_in>;
> + };
> + };
> + };
> +
> + aux-bus {
> + panel {
> + compatible = "edp-panel";
> + power-supply = <&pp3300_disp_x>;
> + backlight = <&backlight_lcd0>;
> + port {
> + panel_in: endpoint {
> + remote-endpoint = <&edp_out>;
> + };
> };
> };
> };
> @@ -929,6 +955,12 @@ pins-cs {
> };
> };
>
> + panel_fixed_pins: panel-pwr-default-pins {
> + pins-vreg-en {
> + pinmux = <PINMUX_GPIO55__FUNC_GPIO55>;
> + };
> + };
> +
> pio_default: pio-default-pins {
> pins-wifi-enable {
> pinmux = <PINMUX_GPIO58__FUNC_GPIO58>;
> --
> 2.40.0
>
>