LINUX下USB1.1设备学习小记(6)_hid与input子系统(3)

static int mousedev_connect(struct input_handler *handler,
             struct input_dev *dev,
             const struct input_device_id *id)
{
    struct mousedev *mousedev;
    int minor;
    int error;
    //历遍mousedev_table数组,寻找一个为空的位置
    for (minor = 0; minor < MOUSEDEV_MINORS; minor++)
        if (!mousedev_table[minor])
            break;
    //检测数组是否满了
    if (minor == MOUSEDEV_MINORS) {
        printk(KERN_ERR "mousedev: no more free mousedev devices\n");
        return -ENFILE;
    }
    //创建一个鼠标设备
    mousedev = mousedev_create(dev, handler, minor);
    if (IS_ERR(mousedev))
        return PTR_ERR(mousedev);
    //添加到mice设备队列中
    error = mixdev_add_device(mousedev);
    if (error) {
        mousedev_destroy(mousedev);
        return error;
    }
    return 0;
}

int input_register_handle(struct input_handle *handle)
{
    struct input_handler *handler = handle->handler;
    struct input_dev *dev = handle->dev;
    int error;
    /*
     * We take dev->mutex here to prevent race with
     * input_release_device().
     */
    error = mutex_lock_interruptible(&dev->mutex);
    if (error)
        return error;
    //连接连接器到设备
    list_add_tail_rcu(&handle->d_node, &dev->h_list);
    mutex_unlock(&dev->mutex);
    synchronize_rcu();
    /*
     * Since we are supposed to be called from ->connect()
     * which is mutually exclusive with ->disconnect()
     * we can't be racing with input_unregister_handle()
     * and so separate lock is not needed here.
     */
    //连接连接器与处理模块
    list_add_tail(&handle->h_node, &handler->h_list);
    //检测处理模块是否有start操作
    if (handler->start)
        handler->start(handle);
    return 0;
}