From: Oliver Neukum <oliver@neukum.org>
To: Paul Fulghum <paulkf@microgate.com>
Subject: Re: [SOLVED] Serial buffer corruption [was Re: FTDI usb-serial possible bug]
Date: Sat, 5 May 2007 18:46:56 +0200
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Cc: Antonino Ingargiola <tritemio@gmail.com>,
       Alan Cox <alan@lxorguk.ukuu.org.uk>,
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Am Samstag, 5. Mai 2007 18:08 schrieb Paul Fulghum:

> If the line discipline throttles the driver input,
> the cdc-acm driver stops giving data to the tty buffering
> and instead stores them internally.

So do usb serial drivers.

> In the serial driver this usually just results in dropping
> RTS to signal the remote end to stop sending. The serial

This may take considerable time in the case of usb devices.

> driver always immediately gives receive data to the tty buffering
> without regard to the throttled state.
> 
> I would argue that cdc-acm should do the same as the serial driver.

Has this been tested?
If so we could reduce the complexity of the throtteling logic in the usb
drivers.

	Regards
		Oliver
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