Note: all the source code contained in this repository is for educational use only, and is provided with no support, endorsement, warranty, guarantee or implied fitness for a particular purpose. It does not constitute sample driver code. Do not reach out to VMware to support this code. Do not copy and reuse in any commercial or product setting.

thgpio

Native ESXi driver for RPi 4's GPIO interface.

Allows controlling the pins of the Raspberry Pi 4's GPIO interface.

Still very much work-in-progress!

Branch main contains:

• the base GPIO hardware driver
• a Python library for interacting with the GPIO MMIO memory directly
• a Python utility for interacting with the GPIO interface
• a Python utility for interacting with the Pimoroni FanShim

Videos

These demos use the Pimoroni FanShim as an example. Any GPIO accessory should work analogously.

Branch main: https://youtu.be/Mw8L1XAi8qA?t=170

Branch fanShimButton: https://youtu.be/YjSxgKr7gZg

Branch charDev: https://youtu.be/Ri1py3AzIsU?t=107

Installation

To install the driver, download the VIB file in the build directory and copy it to your RPi.

Install it as described here: https://kb.vmware.com/s/article/2008939

Note: you will need to reboot the RPi after installing the VIB.

I would recommend downloading the Python library in ./pyUtil/gpioLib/ as well so you don't have to worry about all the bit twiddling.

Post-Installation Setup

You may need to manually change the GPIO_DEVICE_PATH variable in ./pyUtil/gpioLib/__init__.py to reflect the correct name for the character device. This is due to a limitation in the VMKernel character device API.

1. Open the __init__.py file ( https://github.com/thebel1/thgpio/blob/main/pyUtil/gpioLib/__init__.py )
2. Locate the line GPIO_DEVICE_PATH = '/dev/vmgfx32'
3. Run the command ls /dev/ in the ESXi shell and locate the vmgfx* device(s)
4. Note the device number corresponding to the GPIO device 4.1. If you installed the GPIO driver first, the file path should be /dev/vmgfx32 4.2. If you installed the GPIO driver second, the file should be /dev/vmgfx33 4.3. It just keeps counting up from there as far as I can tell
5. Go back to the __init__.py file and set GPIO_DEVICE_PATH to the correct device path
6. Save the file and you're set