staging: speakup: flush tty buffers

[Okash Khawaja]

Hi,

> On 5 May 2017, at 00:21, Samuel Thibault <samuel.thibault at ens-lyon.org> wrote:
> 
> Hello,
> 
> John Covici, on mar. 02 mai 2017 19:05:15 -0400, wrote:
>> Make sure that the modem lines rts-cts are also properly switched.
> 
> Mmm, I'm afraid we forgot to set that.
> 
> It seems RTS/CTS flow control is not enabled by default.

Ah I see. So it is by reading the value returned by set_termios that we know if  RTS/CTS flow control enabled or not. I'm still learning as I have been while working on speakup in general.

> So in ttyio
> we'd need to call tty_set_termios. See how set_termios gets the current
> value, on which we just need to termios.c_cflag |= CRTSCTS before
> calling tty_set_termios.

Sure I'll update the patch. 

Thanks,
Okash