topic Re: Cross-compiling device driver with Visual Studio Code in i.MX Processors

Cross-compiling device driver with Visual Studio Code

hello-world123 — Wed, 24 Nov 2021 06:06:00 GMT

Hello, My name is john. I'm currently building cross-compile environment with visual studio code.

With Variscite's document and NXP's i.MX Porting Guide, I successfully built user-space application cross-compile environment with visual studio code.

The following links are what I referred.

Variscite's document

https://variwiki.com/index.php?title=Yocto_Programming_with_VSCode&release=RELEASE_HARDKNOTT_V1.0_DART-MX8M-MINI#Install_Yocto_Toolchain

NXP's document (2.1.1 How to build and load Kernel in standalone environment)

https://www.nxp.com/docs/en/user-guide/IMX_PORTING_GUIDE.pdf

I want to build device driver with the same method, but I have difficulties about setting kernel headers.

When I bitbake, I added the following to my recipe to include kernel source to sdk which generated by populate_sdk.

TOOLCHAIN_TARGET_TASK_append = " kernel-devsrc"

I made dummy device driver 'dummy.c' in https://github.com/PacktPublishing/Mastering-Embedded-Linux-Programming-Second-Edition/blob/master/Chapter09/dummy-driver/dummy.c

With dummy.c, I run 'make' and VScode show me lots of errors. I think I have to match kernel header carefully, but I don't know how to do.

The following figure is errors which VScode shows to me.

The following figure is my c_cpp_properties.json in VScode and my SDK's location is '/opt/fsl-imx-wayland/4.14-sumo/sysroots/aarch64-poky-linux/*'.

The following figure is my Makefile in VScode.

Thanks for your help.

Re: Cross-compiling device driver with Visual Studio Code

Yuri — Wed, 24 Nov 2021 09:30:26 GMT

@hello-world123
Hello,

VSCode can be used for development of relatively simple applications.
Hardly it is suitable for Linux driver design, since this area is very kernel / version
sensitive. I think it makes sense to rely on standard approaches here.

Regards,
Yuri.

Re: Cross-compiling device driver with Visual Studio Code

bladerunner1010 — Mon, 25 Jul 2022 06:20:07 GMT

Is there a manual for cross compiling?

Re: Cross-compiling device driver with Visual Studio Code

Yuri — Thu, 25 Nov 2021 06:12:24 GMT

@bladerunner1010
Hello,

usually driver sources are provided with instructions how to compile them.

Regards,
Yuri.

Re: Cross-compiling device driver with Visual Studio Code

hello-world123 — Thu, 25 Nov 2021 08:03:53 GMT

Hi, @Yuri . Thank you for your reply.

Your saying is that typical way to develop device driver is like this?

1. Edit/add device driver code and Makefile of kernel source in Yocto build directory with editor like vim.

2. Bitbake to build.

3. Test the device driver

If so, I think it's quite inefficient ways for developing.

According to your mention, am I understand right?

Thanks in advance.

Re: Cross-compiling device driver with Visual Studio Code

Yuri — Thu, 25 Nov 2021 08:50:24 GMT

@hello-world123
Hello,

It would be better to build toolchain, build / load Kernel in standalone environment,
as mentioned in "IMX_PORTING_GUIDE.pdf", unpack driver package with sources
and follow driver's documentation. Yocto approach is not used here.

Regards,
Yuri.