SN65DSI86: sn65dsi86 and mipi dsi connection error

Part Number: SN65DSI86

Tool/software:

I have edp bridge sn65dsi86 i need to connect with mipi dsi. i will share my dts for the same. I am getting an error for bridge attach issue  [ 5.084554] [drm:drm_bridge_attach] *ERROR* failed to attach bridge /soc@0/bus@32c00000/mipi_dsi@32e60000 to encoder DSI-40: -19    what will be the cause for it does i need to enable any configuration for this. i am using a custom board. 

&lcdif1 {
status = "okay";
lcdif1_disp: port@0 {
reg = <0>;

lcdif_to_dsim_1: endpoint {
remote-endpoint = <&dsim_from_lcdif_2>;
};
};
};

&mipi_dsi {
status = "okay";

ports {
#address-cells = <1>;
#size-cells = <0>;
port@0 {
reg = <0>;
dsim_from_lcdif_2: endpoint {
remote-endpoint = <&lcdif_to_dsim_1>;
};
};
port@1 {
reg = <1>;
dsim_to_edpbridge: endpoint {
remote-endpoint = <&edp_bridge_in>;
};
};
};
};


&i2c3{
clock-frequency = <400000>;
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_i2c3>;
status = "okay";


sn65dsi86_bridge: sn65dsi86@2c{
compatible = "ti,sn65dsi86";
reg = <0x2c>;
status ="okay";

pinctrl-names = "default";
pinctrl-0 = <&pinctrl_dp>;

enable-gpios = <&gpio1 5 GPIO_ACTIVE_HIGH>;

vccio-supply = <&vcc_1v8>;
vpll-supply = <&vcc_1v8>;
vcca-supply = <&vcc_1v2>;
vcc-supply = <&vcc_1v2>;

clock-names = "refclk";
clocks = <&refclk>;


ports{
#address-cells = <1>;
#size-cells = <0>;

port@0 {
reg = <0>;

edp_bridge_in: endpoint {
remote-endpoint = <&dsim_to_edpbridge>;
data-lanes = <0 1 2 3>;
};
};
port@1 {
reg = <1>;

edp_bridge_out: endpoint {
remote-endpoint = <&panel_in>;
data-lanes = <0 1 2 3>;
};
};

};
};  

  • Hello, 

    Due to US public holiday, support will resume on Tuesday, September 2nd. Thank you for your patience. 

    Regards, 

    Logan

  • Hi Cyriac,

    As a first step, please initialize the device for test pattern mode. The device will generate an internal test pattern without using DSI inputs and this will confirm whether the downstream DP connection and resolution is working with the attached display.


    For the "bridge attach issue" this may be due to the programming of the SoC/ DSI cource and not related to the DSI86 directly. The DSI86 will only use the DSI input and the initialization sequence (including power-up and DSI configurations) should be followed. The DSI source manual/datasheet may have more information about what the error means. What source are you using here?

    DSI86 Programming guide: 

    Please use this calculator tool to generate the register settings initialization: [FAQ] SN65DSI8x Programming Tools

    The READ ME sheet has information about the steps, and you can enable Color bar pattern for the display. After you enter all the inputs, you can generate the script and program the EVM via I2C.

    This programming guide can also be helpful: https://www.ti.com/lit/ab/slla425/slla425.pdf

    Best regards,
    Ikram