No gpio on BPI M4-zero

jrtaylor · April 30

Looking at the new BPI M4 zero to replace a RPI zero. The official build listed does not have gpio turned or maybe just not built into the kernel. If I download the image from the BPI website it has it but it based on bullseye and the image is broke. I built my own image but still no go so I am not sure what is wrong. I have built images for other boards and projects with success so that's not the problem.

I have a 3.5" TFT touch screen and some relays that I need to run along with a sensor.

c0rnelius · April 30

I suggest looking over the overlays available; https://github.com/BPI-SINOVOIP/pi-linux/tree/pi-6.1-sunxi/arch/arm64/boot/dts/allwinner/overlay

They may or maynot need to be edited as BSP VS MAINLINE usually isn't identical.

iGNUiCould · Tuesday at 11:27 PM

If this is still an issue for anyone, I forked into a repo that is modified to work exclusively with the M4 Zero. Confirmed working on the M4 Zero 4G / 32G model. Should work on other M4 Zero variants as long as the pins are the same.

https://github.com/ignuicould/WiringBPi-M4Zero

I also have pascal bindings for fpc / Lazarus if anyone is interested.

Igor · 2024-11-20T14:31:36Z

15 hours ago, iGNUiCould said:

I forked into a repo that is modified to work exclusively with the M4 Zero.

Take a look at universal projects that are made far better, and are universal by design.
https://forum.armbian.com/forum/40-reviews-tutorials-hardware-hacks/ (pinned topics)

iGNUiCould · 2024-11-21T16:10:36Z

On 11/20/2024 at 9:31 AM, Igor said:

Take a look at universal projects that are made far better, and are universal by design.

Are you saying the repo I posted is low quality because it doesn't contain a ton of extra code for boards I'm not using? I can remove it for you if you disapprove.

Igor · 2024-11-21T16:59:44Z

29 minutes ago, iGNUiCould said:

for boards I'm not using?

When you cloned our repo, you got 10 years of specific work on common work and that was contributed by 500+ people. Most of people are resolving their specific problems, yes, but we all try to do it the way that is reusable, that person behind has less work. We also got a lot of things prepared. Doing things universal should always be considered. Also because you might get help from someone. Which has absolutely same problems, but is having hardware from another vendor.

In our world, SoC defines how things work, not the one that put SoC on PCB and name / sell it. This means that most of the drivers are the same, especially this area is shared - low level communication protocols such as GPIO, I2C, SPI. This is always shared among boards with the same SoC. This goes further. It is shared among same families and we also already have some common generic top level API / libraries that can be used. https://docs.kernel.org/driver-api/gpio/consumer.html (but here my understanding ends, I am not updated with the state of this)

36 minutes ago, iGNUiCould said:

Are you saying the repo I posted is low quality

Yes, it has no point poking into. WiringPi library is a dead project for many years and its no point dealing with this. What vendors do here is, trying to be "as Rpi as possible", so they are doing their quick and dirty assemblies of that, always with partial functionality and absolute absence of maintenance. Their goal is to sell, regardless what is the quality of software. Is that your goal? I doubt.

I am not an expert in this field, so those are general tips, but there are people on and around this forum that knows this stuff well, as they developed those libraries.