usbbus.java

来自「纯java操作系统jnode,安装简单和操作简单的个人使用的Java操作系统」· Java 代码 · 共 56 行

/*
 * $Id: USBBus.java,v 1.1 2003/11/25 11:41:20 epr Exp $
 */
package org.jnode.driver.usb;

import org.jnode.driver.Bus;
import org.jnode.driver.Device;

/**
 * @author epr
 */
public class USBBus extends Bus {

	/** Bitmap with in use device id's */
	private final boolean devIdsInUse[];
	/** The Host Controller API for this bus */
	private final USBHostControllerAPI hcApi;

	/**
	 * @param parent
	 */
	public USBBus(Device parent, USBHostControllerAPI hcApi) {
		super(parent);
		this.hcApi = hcApi;
		this.devIdsInUse = new boolean[128];
	}

	/**
	 * Allocate a new device id.
	 */
	final synchronized int allocDeviceID() {
		final int max = devIdsInUse.length;
		for (int i = 1; i < max; i++) {
			if (!devIdsInUse[i]) {
				devIdsInUse[i] = true;
				return i;
			}
		}
		throw new IllegalArgumentException("Too many allocated USB device id's");
	}

	/**
	 * Free a given device id.
	 */
	final synchronized void freeDeviceID(int devId) {
		devIdsInUse[devId] = false;
	}
	
	/**
	 * @return Returns the hcApi.
	 */
	public USBHostControllerAPI getHcApi() {
		return this.hcApi;
	}
}