Wiznet makers

Linux Driver — W5500 Ethernet

Project Overview
This project aims to deliver a Linux kernel driver for the WIZnet W5500 Ethernet module, making it usable as a standard Ethernet interface (e.g., eth0, eth1) under Linux systems. By integrating SPI communication, device tree configuration, reset control, and interrupt handling, the driver enables embedded Linux boards (including Raspberry Pi, ARM/SoC-based platforms) to communicate over Ethernet using WIZnet W5500.

This work demonstrates WIZnet’s capability in supporting industrial-grade network solutions under Linux, and provides a foundation for R&D in driver optimization, kernel compatibility across versions, and future Single Pair Ethernet (SPE) readiness.

Key Features

Native Linux driver module (or built-into kernel) for WIZnet W5500 over SPI

Device Tree (DT) support: setting up SPI node, CS, IRQ, RST, and other pin configurations

Hardware reset line support (optional) to ensure reliable startup/reset behavior

Network interface registration so users can use standard tools (ifconfig, ip)

Support for both static IP and DHCP methods

Compatibility considerations for different Linux kernel versions

Configuration parameters like SPI speed, interrupt mode, reset polarity, etc.

Hardware Requirements

WIZnet W5500 Module (SPI + CS + RST + optional IRQ)

Linux board / Raspberry Pi or other compatible SoC supporting SPI and Device Tree overlays

Wiring: correct connections of SPI pins (MOSI, MISO, SCLK, CS), reset pin, optional interrupt pin

Usage / Quick Setup Example

Device Tree Overlay / DTS

Define SPI bus node with correct chip-select, reset GPIO, IRQ if used

Specify spi-max-frequency (e.g-40MHz or suitable speed)

Make sure device tree overlay or board file includes W5500 node

Driver Build / Module Loading

Network Interface Configuration

Testing Connectivity

Technical Challenges & Recommendations

SPI Speed Limitations: Higher SPI clock may cause communication errors if hardware wiring/PCB layout is not optimal

Kernel Version Compatibility: Some APIs / DT syntax change across kernel versions → need back-porting / patching for older kernels

Hardware Reset Support: Ensuring physical reset is supported improves reliability in many embedded applications

Interrupt Handling: For some use-cases, IRQ for link status or event notification may improve performance vs polling

R&D & Strategic Significance

Showcases WIZnet W5500 integration in Linux platform → widens market potential into embedded Linux devices

Provides concrete reference for prospective products that use Linux as OS

Enables internal engineering to consider driver performance improvements, maintainability, and future proofing (SPE, etc.)

Helps in drafting product proposals and techno-commercial documents by having Linux driver as a strong feature

Target Applications

Industrial gateways running Linux (Edge computing devices)

IoT routers / bridge devices that require Ethernet interface via SPI

Custom embedded appliances (e.g., data logging, monitoring) that require wired Ethernet connectivity

OEM / ODM products where Linux is base OS and WIZnet is the Ethernet controller

Contributing & Future Development

Test on multiple Linux kernels (e.g. 5.x, 6.x series) and document compatibility matrix

Enhance driver documentation: overlay examples, wiring schematics, board-specific notes

Add automated testing (link up/down, reset cycles, high throughput)

Potential for integrating Modbus TCP or other higher-layer protocols as modules within Linux

Explore SPE usage, possibly building driver variants optimized for SPE phys or minimized wiring