Creating fake/virtual USB devices on macOS using IOUSBHostControllerInterface

// ConsumerKeys.swift // Boot-protocol keyboard that reports keycodes in Consumer page (0x0C). // iOS maps consumer page usages received this way to system actions.

import Foundation

public final class ConsumerKeys: SyntheticHID {

// MARK: - Consumer usages sent as boot-keyboard keycodes (page 0x0C, ≤ 0xFF)

public enum Key: UInt8 {
    case acHome     = 0x40   // Consumer "Menu" → iOS home button
    case mute       = 0xE2
    case volumeUp   = 0xE9
    case volumeDown = 0xEA
    case playPause  = 0xCD
    case nextTrack  = 0xB5
    case prevTrack  = 0xB6
}

// MARK: - Init

public init() {
    super.init(
        reportDescriptor: Self.reportDescriptor,
        reportSize: 8,
        vendorID: 0x05AC,
        productID: 0x0002,
        manufacturer: "Apple Inc.",
        product: "Virtual Consumer Control",
        interfaceSubClass: 0x01,
        interfaceProtocol: 0x01)
}

// MARK: - Key injection

public func keyDown(_ key: Key) {
    sendReport([0, 0, key.rawValue, 0, 0, 0, 0, 0])
}

public func keyUp() {
    clearReport()
}

// MARK: - Report descriptor
// Minimal boot-keyboard shell with Consumer page (0x0C) keycodes.

private static let reportDescriptor: [UInt8] = [
    0x05, 0x0C,  // Usage Page (Consumer)
    0x09, 0x01,  // Usage (Consumer Control)
    0xA1, 0x01,  // Collection (Application)
    0x19, 0x00,  //   Usage Minimum (0)
    0x29, 0xFF,  //   Usage Maximum (255)
    0x15, 0x00,  //   Logical Minimum (0)
    0x25, 0xFF,  //   Logical Maximum (255)
    0x75, 0x08,  //   Report Size (8)
    0x95, 0x08,  //   Report Count (8)
    0x81, 0x00,  //   Input (Data, Array)
    0xC0,        // End Collection
]

}