はじめに

Windowsで組み込み開発をするとき、どうしてもLinuxが必要になることがあるとおもいます。

こちらの記事にある通り、USB-IPD Winを使えばいけます。

usbipd list # usb deviceリスト取得
usbipd attach --busid 2-4 # attach, 管理者権限必要
usbipd bind --busid 2-4 # WSLにbind

が、毎回コマンドを打つのが面倒です。

特に何回も抜き差ししたり、Rebootを繰り返すと、とても面倒です。

というわけで自動化するPythonスクリプトを作ってみました。

スクリプトの使い方

Powershellから下記のようにコマンドを叩くと

usbipd list

下記のように、VID:PIDが出てきます。

Connected:
BUSID  VID:PID    DEVICE                          STATE
2-4    2fe3:0100  USB シリアル デバイス (COM5)     Shared

その中から、WSL2に自動で接続させたいデバイスをスクリプトの中の、

conditions = [
    ["2fe3:0100"],  # USB-CDC
]

の部分に記載します。

デスクトップに*.pyとして保存し、必要な時にダブルクリックして実行すればOKです。

bindが必要なときは管理者権限を要求しますのでOKしてください。

＊ちなみに、上記のVID:PIDはZephyr RTOSのデフォルトのものです。
　こちらの記事で使いました。（宣伝）

スクリプト本体

内容としては、無限ループして該当するbus-idのデバイスにbind/attachするだけです。

"""usbipd_attacher.py."""

import subprocess
import time
import ctypes
from ctypes import windll

"""
Run this script on Windows to automatically attach USB serial devices to WSL.
It uses usbipd-win.
"""

# Define the target USB devices (VendorID:ProductID)
conditions = [
    ["2fe3:0100"],  # Example: USB-CDC
]

# Define excluded bus IDs if necessary
exclude_conditions_bus = []

# Input host IP address if you need to specify host address manually
host_ip = ""


def run_command_as_admin(executable, arguments):
    """
    Execute a command with Administrator privileges using ShellExecuteW.
    This triggers the UAC prompt.
    """
    # 1 = SW_SHOWNORMAL (Show window normally)
    # 0 = SW_HIDE (Hide window - useful if you don't want to see the popup console)
    ret = windll.shell32.ShellExecuteW(
        None, "runas", executable, arguments, None, 1
    )
    return ret > 32  # Returns True if execution was successful (started)


print("Starting usbipd auto-attacher...")

i = 0
while True:
    # Get the list of usbipd devices
    try:
        ret = subprocess.run(["usbipd", "list"], capture_output=True)
        strs = ret.stdout.decode("utf-8")
    except FileNotFoundError:
        print("Error: 'usbipd' command not found. Please install usbipd-win.")
        time.sleep(5)
        continue

    # Initialize exclusion list
    bus_is_excluded = [False] * 20
    
    # Print list periodically for monitoring
    if i % 5 == 0:
        print("")
        print("-------------------- usbipd list -----------------")
        print(strs)
    
    lines = strs.split("\n")
    
    # Update exclusion list based on bus IDs
    for s in lines:
        try:
            for c in exclude_conditions_bus:
                if c in s:
                    # Parse bus ID (assumes single digit for simplicity, adjust if needed)
                    bus_idx = int(s.strip().split(" ")[0].split("-")[0])
                    bus_is_excluded[bus_idx] = True
        except Exception:
            pass

    # Check devices and perform Bind/Attach
    for s in lines:
        try:
            if not s or len(s.split(" ")) < 1:
                continue

            # Parse bus ID to check exclusion
            try:
                # Extracts "1" from "1-2"
                bus_id_str = s.strip().split(" ")[0]
                bus_root = int(bus_id_str.split("-")[0])
                if bus_is_excluded[bus_root]:
                    continue
            except:
                pass # Skip if parsing fails (headers, etc.)

        except Exception:
            continue

        # Check against target conditions
        for cond in conditions:
            is_ok = True
            for c in cond:
                if c not in s:
                    is_ok = False
            
            if not is_ok:
                continue

            # --- Bind Logic (Requires Admin) ---
            if "Not shared" in s:
                print(f"[Action Required] Binding device: {s.strip()}")
                device_id = s.split(" ")[0]
                
                # Execute 'usbipd bind' with Admin privileges
                success = run_command_as_admin("usbipd", f"bind --busid {device_id}")
                
                if success:
                    print("  -> Admin prompt triggered. Waiting for bind to complete...")
                    # Wait for the user to click "Yes" and the bind to finish
                    time.sleep(3) 
                else:
                    print("  -> Failed to trigger admin prompt.")

            # --- Attach Logic (Runs as current user) ---
            elif "Shared" in s:
                # Check if already attached (Depends on usbipd version output)
                if "Attached" in s:
                    continue

                print(f"[Action Required] Attaching device: {s.strip()}")
                device_id = s.split(" ")[0]
                
                cmd = ["usbipd", "attach", "--wsl", "--busid", device_id]
                if host_ip != "":
                    cmd.append("--host-ip")
                    cmd.append(host_ip)
                
                # Run attach command (standard subprocess is usually sufficient for attach)
                subprocess.run(cmd)

    time.sleep(1)
    i += 1