Pin mappings for Milk-V Duo

I received a new RISC-V-based board from Milk-V and started using this library to work with GPIO: https://github.com/warthog618/gpiod. Apparently, the naming scheme in Duo is different from those used in RPi and Banana Pi for which the pin mappings are provided.

I created this tiny module to support Milk-V Duo mappings. It’s not required to be part of the gpiod module so it can be imported separately. See the example below.

Pin naming in Milk-V Duo

In this board there are 5 GPIO chips (gpiochip0 to gpiochip4). The pins are named like GPIOA14, GPIOC9, or PWR_GPIO21 and they are served by different chips. In this case the names above would be translated to gpiochip0 + offset 14, gpiochip2 + offset 9, and gpiochip4 + offset 21 respectively.

Example

package main

import (
	"fmt"
	"log"
	"os"
	"os/signal"
	"syscall"
	"time"

	milkvduo "github.com/pavelanni/gpiod-milkvduo"
	"github.com/warthog618/gpiod"
)

func main() {
	pin := "PWR_GPIO21" // this could be "GPIOA14" or "GPIOC9"
	lineId, err := milkvduo.PinLineID(pin)
	if err != nil {
		log.Fatal(err)
	}

	l, err := gpiod.RequestLine(lineId.Chip, lineId.Offset, gpiod.AsOutput())
	if err != nil {
		log.Fatal(err)
	}

// The rest is the same: you set the line's value, etc.
}

Board info

Here is the official Milk-V Duo documentation: https://milkv.io/docs/duo/overview

More information and guides are available here: https://spotpear.com/index/product/detail/id/1296.html (check the RESOURCES tab for the guides)

This repo contains datasheets and other info for the CPU/TPU used in Duo: https://github.com/sophgocommunity/Duo_Doc/tree/main

Pinout