MIPI Display interface

[jigneshpatel]

Hi,

I am working on i. MX6 Dual Processors with linux kernel revision 4.9.88 and Debian file system . I want to interface COM43H4N10ULC MIPI DSI interface with MX6.

COM43H4N10ULC : https://www.data-modul.com/productfinder/sites/default/files/products/COM%2043H4N10ULC_specification... 

As i know, MIPI DSI support exist in the current kernel by driver. 

I just know i have to do

1. Add configuration of MIPI DSI in device tree file.

2. Display panel porting in linux.

Guide me to achieve this. Did i miss anything?

What other information i need to read for better understand of MIPI display interface.

Thanks,

Jignesh Patel

[joanxie]

pls refer to the patch document as below:

https://community.nxp.com/message/1096015 

[jigneshpatel]

Thanks Joan for guiding,

Now I have changed my device tree as given link as below:

    mxcfb1:fb@0{
        compatible = "fsl,imx6q-mipi-dsi";
        disp_dev = "mipi_dsi";
        interface_pix_fmt = "RGB24";
        lcd_panel = "TRULY-WVGA";
        mode_str ="TRULY-WVGA";
        default_bpp = <24>;
        int_clk = <0>;
        lete_init = <0>;
        status = "okay";
    };

    &mipi_dsi {
        compatible = "fsl,imx6q-mipi-dsi";
        dev_id = <0>;
        disp_id = <1>;
        lcd_panel = "TRULY-WVGA";
        disp-power-on-supply = <&reg_mipi_dsi_pwr_on>;
        reset-gpios = <&gpio5 15 GPIO_ACTIVE_LOW>;
        reset-delay-us = <50000>;
        status = "okay";
    };

But still i am getting error:

    mxc_mipi_dsi 21e0000.mipi: i.MX MIPI DSI driver probed
    mxc_mipi_dsi fb@0: failed to read of property dev_id
    mxc_mipi_dsi: probe of fb@0 failed with error -22

Error is from mipi_dsi.c file.Why it gives the error of dev_id.

Is any other configuration is required for MIPI-DSI and mxcfb1?

Thanks,
Jignesh Patel

[grigoritimonen]

Hi Jignesh,

Did you manage to get display working? I have similar, but 5". Any clues on how to get it working?

[jigneshpatel]

Yes, I got working. what issue are you getting?

Refer my another post you can get the clue from it.

https://community.nxp.com/thread/499983 

[grigoritimonen]

Actually, I have a lot of problems. I have another panel, COM50H5N03ULC. And I have to write a driver for it. It is connected to i.MX8 8MMini-BB development kit.

I didn't check how device tree works for the panel.

I took a Raydium RM67191 driver as a reference.

According to specs https://www.data-modul.com/productfinder/sites/default/files/products/COM%2050H5N03ULC_specification...  panel requires some initialization (page 21 of specs). I have no idea on how to write a data to the panel. There are some functions like mipi_dsi_generic_write() and mipi_dsi_dcs_write_buffer(), but I'm not sure they will do what expected.

[jigneshpatel · Accepted solution]

Hi,

Power on sequence is already given on page 21 on your spec sheet.

you can take mxcfb_hx8369_wvga.c driver for reference, I used it.

BR,

Jignesh Patel