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From: Greg KH <greg@kroah.com>
To: linux-kernel@vger.kernel.org, Alan Cox <alan@lxorguk.ukuu.org.uk>
Subject: Re: Dropped characters in serial connection without flow control
Date: Wed, 28 Oct 2009 11:05:44 -0700	[thread overview]
Message-ID: <20091028180544.GA3523@kroah.com> (raw)
In-Reply-To: <20091028175937.27472.qmail@stuge.se>

On Wed, Oct 28, 2009 at 06:59:37PM +0100, Peter Stuge wrote:
> Peter Stuge wrote:
> > I'm writing a line discipline for a serial port multiplexing
> > hardware
> 
> There is no(!) support for flow control in the hardware.
> 
> Is there anything I can do to reduce serial port interrupt latency or
> otherwise try to mitigate this in my ldisc or in Linux in general? I
> realize that it will never be quite reliable without any flow
> control.

What's wrong with XON/XOFF?  That is a well-known flow control protocol
for systems without hardware support for it.

And since when is adding a UART to a hardware chip expensive these days?

thanks,

greg k-h

  reply	other threads:[~2009-10-28 18:08 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-10-28 17:59 Dropped characters in serial connection without flow control Peter Stuge
2009-10-28 18:05 ` Greg KH [this message]
2009-10-28 18:19   ` Peter Stuge
2009-10-28 18:16 ` Alan Cox

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