RE: [PATCH] USB: serial: ftdi_sio: fix extreme low-latency setting

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From: Johan Hovold
> Sent: 25 January 2017 14:35
> Since commit 557aaa7ffab6 ("ft232: support the ASYNC_LOW_LATENCY
> flag") the FTDI driver has been using a receive latency-timer value of
> 1 ms instead of the device default of 16 ms.
> 
> The latency timer is used to periodically empty a non-full receive
> buffer, but a status header is always sent when the timer expires
> including when the buffer is empty. This means that a two-byte bulk
> message is received every millisecond also for an otherwise idle port as
> long as it is open.
...

I'd wondered what all those packets were.
It seems beyond stupid that the hardware is sending them at all.

	David

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