Hello guys,

 

I've been trying for the past month to get USB OTG and I2C to work on a NanoPI NEO AIR running Armbian, without any success. For OTG what I've tried was adding the following to "sun8i-h3-nanopi-neo-air.dts":

 

&usb_otg {
        dr_mode = "otg";
        status = "okay";
};

I have also enabled OTG and I2C in the kernel config menu, but for I2C I couldn't find what to put inside the DTS file.

 

Can someone give me pointers on how to solve this, please? Yes, I am a very inexperienced developer when it comes to embedded systems and have very poor understanding of how to properly configure a device tree source file. Any help would be deeply appreciated. Thank you.

I don't know much about device tree overlays or kernel configs, since there hasn't been a compulsion for me to learn.... yet  but I have been able to get i2c screens and Serial over USB via OTG working on the NanoPi NeoAir.

And by 'I' Have, I mean others have lead the way and I've stood on their shoulders  Don't know what exactly you wanna do with i2c/OTG on NPNA but maybe you'll find something useful here: https://github.com/BiTinerary/PocketServerPi

It's the best I can offer, otherwise you'll have to wait for better, more experienced, specific direction. Good luck.

@Vitor Falcão

Check this docs: https://docs.armbian.com/User-Guide_Allwinner_overlays/

 

OTG implementation might not be fully ready/broken in this kernel: http://linux-sunxi.org/Linux_mainlining_effort#Status_Matrix

@Igor

I had tried what's on the docs before, but it didn't work =/ I am now playing with the DTS, basing myself on the orangepi DTS, but so far I haven't succeeded.

 

About the OTG, I don't know if I am testing it correctly. What I do is the following:

 

modprobe gadgetfs
sudo mkdir /dev/gadget
sudo mount -t gadgetfs gadgetfs /dev/gadget
ls /dev/gadget

But it fails on the third command (sudo mount...). It says: mount: unknown filesystem type 'gadgetfs'. Is this the right way to test it? lsmod shows that gadgetfs is loaded. Thank you.