Function rt_serial_control

components/drivers/serial/dev_serial_v2.c:1378–1779

* @brief Control the serial device. * @param dev The pointer of device driver structure * @param cmd The command value that controls the serial device * @param args The parameter value that controls the serial device * @return Return the status of the operation. */

  * @return Return the status of the operation.
  */
static rt_err_t rt_serial_control(struct rt_device *dev,
                                  int               cmd,
                                  void             *args)
{
    rt_err_t                 ret = RT_EOK;
    struct rt_serial_device *serial;

    RT_ASSERT(dev != RT_NULL);
    serial = (struct rt_serial_device *)dev;

    switch ((rt_ubase_t)cmd)
    {
    case RT_DEVICE_CTRL_SUSPEND:
        /* suspend device */
        dev->flag |= RT_DEVICE_FLAG_SUSPENDED;
        break;

    case RT_DEVICE_CTRL_RESUME:
        /* resume device */
        dev->flag &= ~RT_DEVICE_FLAG_SUSPENDED;
        break;

    case RT_DEVICE_CTRL_CONFIG:
        if (args == RT_NULL)
        {
            ret = -RT_EINVAL;
        }
        else
        {
            struct serial_configure *pconfig = (struct serial_configure *)args;
            if (((pconfig->rx_bufsz != serial->config.rx_bufsz)
                 || (pconfig->tx_bufsz != serial->config.tx_bufsz)
#ifdef RT_SERIAL_USING_DMA
                 || (pconfig->dma_ping_bufsz != serial->config.dma_ping_bufsz)
#endif
                     )
                && serial->parent.ref_count != 0)
            {
                /*can not change buffer size*/
                ret = -RT_EBUSY;
                break;
            }
            /* set serial configure */
            serial->config = *pconfig;
            serial->ops->configure(serial, (struct serial_configure *)args);
        }
        break;
    case RT_SERIAL_CTRL_GET_CONFIG:
        if (args == RT_NULL)
        {
            ret = -RT_EINVAL;
        }
        else
        {
            struct serial_configure *pconfig = (struct serial_configure *)args;
            *pconfig                         = serial->config;
        }
        break;