i.MX ProcessorsのトピックRe: MIPI Display interface

MIPI Display interface

jigneshpatel — Tue, 05 Mar 2019 05:08:31 GMT

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_12015179.pdf

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

Re: MIPI Display interface

joanxie — Mon, 11 Mar 2019 03:16:16 GMT

pls refer to the patch document as below:

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

Re: MIPI Display interface

jigneshpatel — Sat, 06 Apr 2019 13:36:37 GMT

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

Re: MIPI Display interface

grigoritimonen — Fri, 24 May 2019 07:49:17 GMT

Hi Jignesh,

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

Re: MIPI Display interface

jigneshpatel — Mon, 27 May 2019 08:03:13 GMT

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

Re: MIPI Display interface

grigoritimonen — Fri, 31 May 2019 12:42:24 GMT

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_12029172.pdf 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.

Re: MIPI Display interface

jigneshpatel — Wed, 05 Jun 2019 05:50:52 GMT

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