Return-Path: Received: from mail-lf0-f65.google.com ([209.85.215.65]:35638 "EHLO mail-lf0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753938AbcI2LZU (ORCPT ); Thu, 29 Sep 2016 07:25:20 -0400 From: Johan Hovold To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , linux-usb@vger.kernel.org, Konstantin Shkolnyy , Johan Hovold Subject: [PATCH stable-4.4] USB: serial: cp210x: fix hardware flow-control disable Date: Thu, 29 Sep 2016 13:24:31 +0200 Message-Id: <1475148271-6456-1-git-send-email-johan@kernel.org> Sender: stable-owner@vger.kernel.org List-ID: From: Konstantin Shkolnyy commit a377f9e906af4df9071ba8ddba60188cb4013d93 upstream A bug in the CRTSCTS handling caused RTS to alternate between CRTSCTS=0 => "RTS is transmit active signal" and CRTSCTS=1 => "RTS is used for receive flow control" instead of CRTSCTS=0 => "RTS is statically active" and CRTSCTS=1 => "RTS is used for receive flow control" This only happened after first having enabled CRTSCTS. Signed-off-by: Konstantin Shkolnyy Fixes: 39a66b8d22a3 ("[PATCH] USB: CP2101 Add support for flow control") [johan: reword commit message ] Signed-off-by: Johan Hovold [johan: backport to 4.4 ] Signed-off-by: Johan Hovold --- This is a backport of an upstream fix to v4.4, which should apply too earlier stable trees as well. Johan drivers/usb/serial/cp210x.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c index a2b43a6e7fa7..c33dfff81cd3 100644 --- a/drivers/usb/serial/cp210x.c +++ b/drivers/usb/serial/cp210x.c @@ -784,7 +784,7 @@ static void cp210x_set_termios(struct tty_struct *tty, } else { modem_ctl[0] &= ~0x7B; modem_ctl[0] |= 0x01; - modem_ctl[1] |= 0x40; + modem_ctl[1] = 0x40; dev_dbg(dev, "%s - flow control = NONE\n", __func__); } -- 2.7.3