Build unknown mraa platform

[kleysoncastro]

When the lib mraa is installed with apt it receives this MRAA version (v2.1.0-22-gb24cd50) on the Radxa ROCK Pi S.

• When done using buildroot, the version looks like this. Version 2022.02.1 on Unknown platform

code

#include <iostream>
#include <mraa.hpp>

int main() {
    // Inicializar o barramento I2C
    mraa::I2c i2c(0);  // O número 0 refere-se ao barramento I2C 0

    // Verificar se o barramento I2C foi inicializado corretamente
    if (!i2c.address(0x0A)) {
        std::cerr << "Erro ao inicializar o barramento I2C" << std::endl;
        return 1;
    }

    // Ler um byte do dispositivo no endereço 0x0A
    uint8_t dataRead;
    if (i2c.read(&dataRead, 1) != mraa::SUCCESS) {
        std::cerr << "Erro ao ler do dispositivo I2C" << std::endl;
        return 1;
    }

    std::cout << "Valor lido: " << static_cast<int>(dataRead) << std::endl;

    return 0;
}

• The code above runs normally in the debian version, in the version with buildroot I have this error

# ./i2c-list 
terminate called after throwing an instance of 'std::invalid_argument'
  what():  Invalid i2c bus
Aborted

Using, it ok

# i2cdetect -y 0
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- 0a -- -- -- -- -- 
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
70: -- -- -- -- -- -- -- --                         

I don't know if it's appropriate to open an issue here, but I would like to compile this mraa lib to run on my image. can you help me ?

[haelyons]

There could be a couple reasons for this; have you checked that upstream mraa supports ROCK Pi S, and are you using the default mraa package in Buildroot?

Are you using the default mraa package within Buildroot? I had this issue when cross-compiling a custom mraa version and it was due to the correct headers not being installed.

[kleysoncastro]

There could be a couple reasons for this; have you checked that upstream mraa supports ROCK Pi S, and are you using the default mraa package in Buildroot?

Are you using the default mraa package within Buildroot? I had this issue when cross-compiling a custom mraa version and it was due to the correct headers not being installed.

Yes, it is buildroot's own mraa lib.
If you look carefully in the buildroot/package/mrra directory
there is a *.pach correction that is to correct an import of a global variable.
1 Taking this into account, one of the ways to build mrra for RK03308 is to fork mraa on radxa's github, and apply the patch.
2 you can fork the radxa mrra lib and in the buildroot/package/mrra/mraa.mk directory change the flag #MRAA_SITE = $(call github,eclipse,mraa,v$(MRAA_VERSION)) to MRAA_SITE = https://github.com/kleysoncastro/mraa/archive/refs/tags.
of this "source" farm, you need to tag it in the lib,
but you can copy this line (MRAA_SITE = https://github.com/kleysoncastro/mraa/archive/refs/tags), then buildroot will do it in my repo. Hope this helps.