static int32_t SampleAttach(struct UartHost *host, struct HdfDeviceObject *device)
{
    int32_t ret;
    struct UartDevice *uartDevice = NULL;
    if (device->property == NULL) {
        HDF_LOGE("%s: property is NULL", __func__);
        return HDF_FAILURE;
    }
    uartDevice = (struct UartDevice *)OsalMemCalloc(sizeof(struct UartDevice));
    if (uartDevice == NULL) {
        HDF_LOGE("%s: OsalMemCalloc uartDevice error", __func__);
        return HDF_ERR_MALLOC_FAIL;
    }
    SampleDispatchConstruct(uartDevice);
    device->service = &uartDevice->ioService; // 服务应该在HdfUartSampleBind方法中进行绑定
    ret = UartDeviceGetResource(uartDevice, device->property);
    if (ret != HDF_SUCCESS) {
        (void)OsalMemFree(uartDevice);
        return HDF_FAILURE;
    }
    host->num = uartDevice->resource.num;
    host->priv = uartDevice;
    UartSampleAddDev(host);
    return UartDeviceInit(uartDevice);
}