Re: [PATCH 2/2] arm64: dts: imx8mp-beacon: Enable LVDS-1

From: Marco Felsch
Date: Fri Mar 01 2024 - 03:58:36 EST


Hi Adam,

On 24-02-29, Adam Ford wrote:
> Beacon has an LVDS display that can connect to one of the
> LVDS ports on the baseboard. The display requires a 30MHz
> clock to display properly, and the LDB needs to run at 7x that.
> With the audio CODEC now moved to the AUDIO_PLL1, the AUDIO_PLL2
> is now available to source the LDB at 210MHz and the DISP_PIX2.
>
> Signed-off-by: Adam Ford <aford173@xxxxxxxxx>
>
> diff --git a/arch/arm64/boot/dts/freescale/imx8mp-beacon-kit.dts b/arch/arm64/boot/dts/freescale/imx8mp-beacon-kit.dts
> index 1f827ef38e36..731ee2667060 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mp-beacon-kit.dts
> +++ b/arch/arm64/boot/dts/freescale/imx8mp-beacon-kit.dts
> @@ -19,6 +19,26 @@ aliases {
> ethernet1 = &fec;
> };
>
> + backlight: backlight {
> + compatible = "pwm-backlight";
> + pwms = <&pwm2 0 100000 0>;
> + power-supply = <&reg_lcd1_reset>;
> + status = "okay";

status is not required here.

> +
> + brightness-levels = < 0 1 2 3 4 5 6 7 8 9
> + 10 11 12 13 14 15 16 17 18 19
> + 20 21 22 23 24 25 26 27 28 29
> + 30 31 32 33 34 35 36 37 38 39
> + 40 41 42 43 44 45 46 47 48 49
> + 50 51 52 53 54 55 56 57 58 59
> + 60 61 62 63 64 65 66 67 68 69
> + 70 71 72 73 74 75 76 77 78 79
> + 80 81 82 83 84 85 86 87 88 89
> + 90 91 92 93 94 95 96 97 98 99
> + 100>;

Are you aware of: 'num-interpolated-steps' to avoid such arrays?

> + default-brightness-level = <80>;
> + };
> +
> chosen {
> stdout-path = &uart2;
> };
> @@ -135,6 +155,38 @@ led-3 {
> };
> };
>
> + lvds-1 {
> + compatible = "panel-lvds";
> + power-supply = <&reg_lcd1>;
> + width-mm = <223>;
> + height-mm = <125>;
> + backlight = <&backlight>;
> + data-mapping = "vesa-24";
> +
> + panel-timing {
> + /* 800x480@60Hz */
> + clock-frequency = <30000000>;
> + hactive = <800>;
> + vactive = <480>;
> + hsync-len = <48>;
> + hfront-porch = <40>;
> + hback-porch = <40>;
> + vfront-porch = <13>;
> + vback-porch = <29>;
> + vsync-len = <1>;
> + hsync-active = <1>;
> + vsync-active = <3>;
> + de-active = <1>;
> + pixelclk-active = <0>;
> + };

I would like to have a proper panel-simple.c entry but that's just my
POV of adding panels.

> +
> + port {
> + panel1_in: endpoint {
> + remote-endpoint = <&ldb_lvds_ch1>;
> + };
> + };
> + };
> +
> reg_audio: regulator-wm8962 {
> compatible = "regulator-fixed";
> regulator-name = "3v3_aud";
> @@ -144,6 +196,25 @@ reg_audio: regulator-wm8962 {
> enable-active-high;
> };
>
> + reg_lcd1_reset: regulator-lcd1-reset {
> + compatible = "regulator-fixed";
> + regulator-name = "LVDS-1 reset";
> + regulator-min-microvolt = <3300000>;
> + regulator-max-microvolt = <3300000>;
> + gpio = <&pca6416_3 13 GPIO_ACTIVE_HIGH>;
> + enable-active-high;
> + vin-supply = <&reg_lcd1>;
> + };

This reset "regulator" seems more like a workaround, why don't you use
the reset-gpios property from "panel-lvds"?

Regards,
Marco

> +
> + reg_lcd1: regulator-lcd1 {
> + compatible = "regulator-fixed";
> + regulator-name = "lvds-1 power";
> + regulator-min-microvolt = <3300000>;
> + regulator-max-microvolt = <3300000>;
> + gpio = <&pca6416_3 14 GPIO_ACTIVE_HIGH>;
> + enable-active-high;
> + };
> +
> reg_usdhc2_vmmc: regulator-usdhc2 {
> compatible = "regulator-fixed";
> regulator-name = "VSD_3V3";
> @@ -457,6 +528,38 @@ &lcdif1 {
> status = "okay";
> };
>
> +&lcdif2 {
> + status = "okay";
> +};
> +
> +&lvds_bridge {
> + assigned-clocks = <&clk IMX8MP_CLK_MEDIA_LDB>, <&clk IMX8MP_AUDIO_PLL2_OUT>;
> + assigned-clock-parents = <&clk IMX8MP_AUDIO_PLL2_OUT>;
> + assigned-clock-rates = <210000000>, <210000000>;
> + status = "okay";
> +
> + ports {
> + port@2 {
> + ldb_lvds_ch1: endpoint {
> + remote-endpoint = <&panel1_in>;
> + };
> + };
> + };
> +};
> +
> +&media_blk_ctrl {
> + assigned-clocks = <&clk IMX8MP_CLK_MEDIA_AXI>,
> + <&clk IMX8MP_CLK_MEDIA_APB>,
> + <&clk IMX8MP_CLK_MEDIA_DISP1_PIX>,
> + <&clk IMX8MP_CLK_MEDIA_DISP2_PIX>,
> + <&clk IMX8MP_VIDEO_PLL1>;
> + assigned-clock-parents = <&clk IMX8MP_SYS_PLL2_1000M>,
> + <&clk IMX8MP_SYS_PLL1_800M>,
> + <&clk IMX8MP_VIDEO_PLL1_OUT>,
> + <&clk IMX8MP_AUDIO_PLL2_OUT>;
> + assigned-clock-rates = <500000000>, <200000000>, <0>, <0>, <1039500000>;
> +};
> +
> &micfil {
> pinctrl-names = "default";
> pinctrl-0 = <&pinctrl_pdm>;
> @@ -496,6 +599,12 @@ &pcie_phy {
> status = "okay";
> };
>
> +&pwm2 {
> + status = "okay";
> + pinctrl-names = "default";
> + pinctrl-0 = <&pinctrl_pwm2>;
> +};
> +
> &sai3 {
> pinctrl-names = "default";
> pinctrl-0 = <&pinctrl_sai3>;
> @@ -596,6 +705,13 @@ &usdhc2 {
> };
>
> &iomuxc {
> +
> + pinctrl_pwm2: pwm2grp {
> + fsl,pins = <
> + MX8MP_IOMUXC_GPIO1_IO09__PWM2_OUT 0x116
> + >;
> + };
> +
> pinctrl_ecspi2: ecspi2grp {
> fsl,pins = <
> MX8MP_IOMUXC_ECSPI2_SCLK__ECSPI2_SCLK 0x82
> --
> 2.43.0
>
>
>