Date: Fri, 8 Jun 2007 12:48:53 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: David Woodhouse <dwmw2@infradead.org>
Cc: akpm@osdl.org, linux-kernel@vger.kernel.org, paulus@samba.org
Subject: Re: [SERIAL] Don't optimise away baud rate changes when BOTHER is
 used
Message-ID: <20070608124853.5fdfaee2@the-village.bc.nu>
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> It works fine. The only problem is that if I set a _standard_ baud rate
> with BOTHER and then read it back with something that doesn't grok
> BOTHER, I get it back just as I set it.

That seemed to me to be the right thing to do.

> It might be better if it was returning B38400, rather than BOTHER.
> Should we be using tty_termios_encode_baud_rate() for TCGETS()?

You can't really do that as you get weird behaviour then when people do

	tcgetattr
		|= BOTHER;
		speed = 19200;
	tcsetattr

later in the same app

	tcgetattr
		speed = 38400
	tcsetattr

knowing that they set BOTHER already.

I guess you could add both ioctl sets anyway but the plan longer term is
for glibc tcsetattr/getattr to do the right thing with the new ioctls in
all cases, as the glibc interface already provides speed fields.
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