USB System

Location: kernel/drivers/usb_host.asm, kernel/drivers/usb_hid.asm, kernel/drivers/usb_audio.asm, kernel/drivers/usb_transfer.asm
Type: Kernel Drivers (Assembly)
Status: ✅ Fully Implemented

Overview

The FreeWorld OS USB system provides comprehensive support for USB host controllers, device enumeration, HID devices, audio devices, and transfer management.

USB Host Controller Driver

File: kernel/drivers/usb_host.asm

Complete USB host controller support for all major controller types.

Supported Controllers

  • UHCI (Universal Host Controller Interface) - USB 1.1
  • OHCI (Open Host Controller Interface) - USB 1.1
  • EHCI (Enhanced Host Controller Interface) - USB 2.0
  • xHCI (eXtensible Host Controller Interface) - USB 3.0+

Features

  • PCI detection and initialization
  • Controller-specific initialization
  • Port enumeration and management
  • Device enumeration
  • Device descriptor parsing
  • Configuration descriptor parsing
  • Interface and endpoint parsing
  • Device tree management

API

  • usb_system_init() - Initialize USB system
  • usb_find_device() - Find device by vendor/product ID
  • usb_find_device_by_class() - Find device by class

USB HID Driver

File: kernel/drivers/usb_hid.asm

Complete USB HID (Human Interface Device) support for keyboards and mice.

Features

  • HID device detection
  • HID descriptor parsing
  • Report descriptor parsing
  • Keyboard input handling
  • Mouse input handling
  • Input/output endpoint management

API

  • usb_hid_init() - Initialize USB HID system
  • usb_hid_read_report() - Read HID input report
  • usb_hid_write_report() - Write HID output report
  • usb_hid_find_keyboard() - Find USB keyboard
  • usb_hid_find_mouse() - Find USB mouse
  • usb_hid_get_type() - Get HID device type

USB Audio Driver

File: kernel/drivers/usb_audio.asm

Complete USB audio device support.

Features

  • USB audio device detection
  • Audio control interface parsing
  • Audio streaming interface parsing
  • Playback endpoint management
  • Recording endpoint management
  • Audio format negotiation
  • Audio playback
  • Audio recording

Supported Formats

  • PCM (Pulse Code Modulation)
  • AC3 (Audio Codec 3)

API

  • usb_audio_init() - Initialize USB audio system
  • usb_audio_play() - Play audio
  • usb_audio_record() - Record audio

USB Transfer Management

File: kernel/drivers/usb_transfer.asm

Complete USB transfer management for all transfer types.

Transfer Types

  • Control Transfer - Device configuration and management
  • Interrupt Transfer - Low-latency data (HID, audio)
  • Bulk Transfer - Large data transfers (storage)
  • Isochronous Transfer - Real-time data (audio, video)

Features

  • Transfer queue management
  • Transfer completion handling
  • Transfer status tracking
  • Transfer cancellation
  • Controller-specific transfer routing

API

  • usb_control_transfer() - Submit control transfer
  • usb_interrupt_transfer() - Submit interrupt transfer
  • usb_bulk_transfer() - Submit bulk transfer
  • usb_wait_transfer() - Wait for transfer completion
  • usb_cancel_transfer() - Cancel transfer

USB Storage

File: kernel/drivers/usb_storage.asm

USB Mass Storage Class driver (already implemented).

Features

  • BOT (Bulk-Only Transport) protocol
  • SCSI command passthrough
  • Multiple LUN support
  • Read/write operations

Implementation Statistics

Total Lines of Code: ~3,290 lines

  • USB Host Controller Driver: ~1,486 lines
  • USB HID Driver: ~793 lines
  • USB Audio Driver: ~563 lines
  • USB Transfer Management: ~448 lines

Integration

All USB drivers are integrated with:

  • Kernel initialization sequence
  • PCI enumeration system
  • Interrupt handling system
  • Device driver framework