Re: [v2.6.34-stable 137/165] USB: Fix Corruption issue in USB ftdidriver ftdi_sio.c

[Herton Ronaldo Krzesinski]

On Wed, Aug 15, 2012 at 03:48:01PM -0400, Paul Gortmaker wrote:
> From: Andrew Worsley <amworsley@xxxxxxxxx>
> 
>                    -------------------
>     This is a commit scheduled for the next v2.6.34 longterm release.
>     http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git
>     If you see a problem with using this for longterm, please comment.
>                    -------------------
> 
> commit b1ffb4c851f185e9051ba837c16d9b84ef688d26 upstream.
> 
> Fix for ftdi_set_termios() glitching output
> 
> ftdi_set_termios() is constantly setting the baud rate, data bits and parity
> unnecessarily on every call, . When called while characters are being
> transmitted can cause the FTDI chip to corrupt the serial port bit stream
> output by stalling the output half a bit during the output of a character.
> Simple fix by skipping this setting if the baud rate/data bits/parity are
> unchanged.
> 
> Signed-off-by: Andrew Worsley <amworsley@xxxxxxxxx>
[...]

commit 108e02b12921078a59dcacd048079ece48a4a983 ("USB: ftdi_sio: fix
initial baud rate") says it addresses a regression on this change,
something to consider for inclusion with this update.

-- 
[]'s
Herton
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/