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Date: Mon, 12 May 2008 11:44:07 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Bryan Wu <cooloney@kernel.org>
Cc: linux-kernel@vger.kernel.org, Oleksiy Kebkal <kebkal@gmail.com>,
       Oleksiy Kebkal <lesha@evologics.de>,
       Russell King <rmk@arm.linux.org.uk>,
       Andrew Morton <akpm@linux-foundation.org>,
       Bryan Wu <cooloney@kernel.org>
Subject: Re: [PATCH 1/1] [serial/core]: This patch leaves RTS alone when
 CRTSCTS is not set.
Message-ID: <20080512114407.1dd79301@core>
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References: <1210587614-10016-1-git-send-email-cooloney@kernel.org>
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> +			 * Setup the RTS (in the case of hardware flow control)
> +			 * and DTR signals once the port is open and ready to
> +			 * respond.
>  			 */
> -			if (info->tty->termios->c_cflag & CBAUD)
> -				uart_set_mctrl(port, TIOCM_RTS | TIOCM_DTR);
> +			if (info->tty->termios->c_cflag & CBAUD) {
> +				uart_set_mctrl(port, TIOCM_DTR);
> +				if (info->flags & UIF_CTS_FLOW)
> +					uart_set_mctrl(port, TIOCM_RTS);
> +			}

Seems fine but we've now got 5 line blocks of duplicated code - and code
we will need to complicate further in future if we add other flow control
systems.

statc void uart_set_flow_control(port, int onoff)
{
	..
}

Would be worth writing and using for these cases

(Yes I am being fussy: I am currently trying to stamp out lots of code
duplication in the tty and serial layers so I don't want more added as it
is getting out of hand)

Alan