HDMI LCD vignetted border issue with iMX6 based Udoo Neo board

Question

I am struggling to find out the issue with is happened in my HDMI display and I can't find any solution

I used udoo neo board with android os And I have one HDMI LCD with touch display https://shop.udoo.org/7inch-hdmi-usb-display-touch.html

LCDis working fine with PC and Raspberry Pi 3 but when I connect this display to my Udoo Neo board it show vignetted screen border as below:

The DTS file has:

 / {
        codec_hdmi: hdmi-codec {
            compatible = "udoo,tda19988-codec";
            status = "okay";
        };

        sound_hdmi {
            compatible = "udoo,audio-tda19988";
            model = "imx6sx-tda19988";
            cpu-dai = <&ssi2>;
            audio-codec = <&codec_hdmi>;
            mux-int-port = <2>;
            mux-ext-port = <5>;
            ssi-controller = <&ssi2>;
            status = "okay";
        };

    };

    &i2c3 {
        status = "okay";

        tda19988: tda19988@34 {
            compatible = "udoo,tda19988";
            reg = <0x34>;
            status = "okay";
        };
    };

    &lcdif1 {
        pinctrl-names = "default";
        pinctrl-0 = <&pinctrl_lcdif_dat_0
        &pinctrl_lcdif_ctrl_0>;
        lcd-supply = <&vgen5_reg>;
        display = <&display0>;
        status = "okay";

        display0: display {
            bits-per-pixel = <32>;
            bus-width = <24>;

            display-timings {
                native-mode = <&timing0>;
                timing0: timing0 {
                    clock-frequency = <74250000>;
                    hactive = <1280>;
                    vactive = <720>;
                    hback-porch = <220>;
                    hfront-porch = <110>;
                    vback-porch = <20>;
                    vfront-porch = <5>;
                    hsync-len = <40>;
                    vsync-len = <5>;

                    hsync-active = <0>;
                    vsync-active = <1>;
                    de-active = <1>;
                    pixelclk-active = <0>;
                };
            };
        };
    };

    &dcic1 {
        dcic_id = <0>;
        dcic_mux = "dcic-lcdif1";
        status = "okay";
    };

    &ssi2 {
        fsl,mode = "i2s-master";
        status = "okay";
    };

    &audmux {
        pinctrl-names = "default";
        pinctrl-0 = <&pinctrl_audmux_hdmi>;
        status = "okay";
    };

I don't know why this happening please help me

Looks like a hardware or video driver / configuration issue - probably off-topic for SO unless there's code involved. Are you running it at the native resolution of the screen? — Clifford, Feb 21 '20 at 09:47
thanks for replay, no not running on native resolution. I adit my dts file with lock-frequency = 32000000; hactive = 1024; vactive = 600; hback-porch = 40; hfront-porch = 40; vback-porch = 29; vfront-porch = 13; hsync-len = 48; vsync-len = 3; hsync-active = 0; vsync-active = 0; de-active = 1; pixelclk-active = 0; — Dimpu10, Feb 21 '20 at 12:17
Definitely off topic. Since the screen and board are from the same vendor, probably best asked at https://www.udoo.org/forum where someone is likely to have got this combination working. — Clifford, Feb 21 '20 at 12:54
Put relevant information in the question, not in the comments. Include the DTS content in the question. — Clifford, Feb 21 '20 at 20:43
The [screen manufacurer's site](https://www.waveshare.com/wiki/7inch_HDMI_LCD_(C)#Working_with_Raspberry_Pi) has settings for RPi which may be relevant. I would suggest starting in native resolution first. — Clifford, Feb 21 '20 at 20:56
yes you are right but no one gives the answer at udoo.org/forum — Dimpu10, Feb 24 '20 at 05:07

score 0 · Answer 1 · answered Feb 25 '20 at 22:47

The timings suggested at https://tinkerboarding.co.uk/forum/thread-670-post-3018.html#pid3018 for a similar display suggest:

        display-timings {
            native-mode = <&timing0>;
            timing0: timing0 {
                clock-frequency = <74250000>;
                hactive = <1024>;
                vactive = <600>;
                hback-porch = <160>;
                hfront-porch = <24>;
                vback-porch = <29>;
                vfront-porch = <3>;
                hsync-len = <136>;
                vsync-len = <6>;

                hsync-active = <0>;
                vsync-active = <0>;
                de-active = <1>;
                pixelclk-active = <0>;
            };

But I am no expert. But setting the native-mode to something other then the display's native mode makes little sense. It should be your starting point.

HDMI LCD vignetted border issue with iMX6 based Udoo Neo board

1 Answers1