54e2bcc7ad
current baudrate setting. Use this ioctl() when we don't know the baudrate of the sysdev (as represented by a 0 value). When the ioctl() fails, e.g. when the backend hasn't implemented it or the hardware doesn't provide the means to determine its current baudrate setting, we invalidate the baudrate setting by setting it to -1. None of the backends currently implement the new ioctl().