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Date: Wed, 10 May 2017 20:41:51 +0100
From: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
To: okash.khawaja@gmail.com
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Samuel Thibault <samuel.thibault@ens-lyon.org>,
        linux-kernel@vger.kernel.org, William Hubbs <w.d.hubbs@gmail.com>,
        Chris Brannon <chris@the-brannons.com>, Kirk Reiser <kirk@reisers.ca>,
        speakup@linux-speakup.org, devel@driverdev.osuosl.org,
        John Covici <covici@ccs.covici.com>
Subject: Re: [patch 1/1] staging: speakup: flush tty buffers and ensure
 hardware flow control
Message-ID: <20170510204151.43986689@alans-desktop>
In-Reply-To: <20170509124238.139472887@gmail.com>
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        <20170509124238.139472887@gmail.com>
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> +	if (!(tmp_termios.c_cflag & CRTSCTS)) {
> +		tmp_termios.c_cflag |= CRTSCTS;
> +		ret = tty_set_termios(tty, &tmp_termios);
> +		if (ret)
> +			pr_warn("speakup: Failed to set hardware flow control\n");

You should check the tty c_cflag after the call rather than rely on an
error code. Strictly speaking tty_set_termios should error if no tty bits
are changed by the request but it never has on Linux. Instead check the
tty gave you the result you wanted.

Alan