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Message-ID: <d120d50005012712411b6a1bf7@mail.gmail.com>
Date: Thu, 27 Jan 2005 15:41:32 -0500
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reply-To: dtor_core@ameritech.net
To: Andries Brouwer <aebr@win.tue.nl>
Subject: Re: i8042 access timings
Cc: Linus Torvalds <torvalds@osdl.org>, Jaco Kroon <jaco@kroon.co.za>,
       sebekpi@poczta.onet.pl, Vojtech Pavlik <vojtech@suse.cz>,
       Andrew Morton <akpm@osdl.org>, linux-kernel@vger.kernel.org
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On Thu, 27 Jan 2005 21:29:47 +0100, Andries Brouwer <aebr@win.tue.nl> wrote:
> On Thu, Jan 27, 2005 at 10:09:24AM -0800, Linus Torvalds wrote:
> 
> > So what _might_ happen is that we write the command, and then
> > i8042_wait_write() thinks that there is space to write the data
> > immediately, and writes the data, but now the data got lost because the
> > buffer was busy.
> 
> Hmm - I just answered the same post and concluded that I didnt understand,
> so you have progressed further. I considered the same possibility,
> but the data was not lost since we read it again later.
> Only the ready flag was lost.
> 

No, note that if there was valid data we would dee 0xa5 instead of
0x5a that was in the buffer - because in i8042_command we invert data
coming from AUX port. So Linus's theory seems feasible.
 

-- 
Dmitry
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