From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64C26C433FE for ; Mon, 28 Feb 2022 18:10:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237549AbiB1SLd (ORCPT ); Mon, 28 Feb 2022 13:11:33 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60336 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241168AbiB1SJc (ORCPT ); Mon, 28 Feb 2022 13:09:32 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 465B7888F1; Mon, 28 Feb 2022 09:49:37 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id C7214CE17C4; Mon, 28 Feb 2022 17:49:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C70ABC340E7; Mon, 28 Feb 2022 17:49:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1646070571; bh=o+Zbj5gKSwYE13o0HjjCs07AfQPVB2F5VfONz0njsJ8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=T1Bjhn1xnSnx6hKkrrJGpuNTN6mQDArdrZNk4/yV06RdxOQGNgABFSHcWh4uko+h6 QT7D40wbY5R4KcMAbGgQaOIYXGTqwTbuxn4+v8mxU0Z0eJ0DlzWp2LCrSTO9HXypLY YvGgX1fH/0/vLthbmQ2jMVFpPwdSX7YYGoWXdufQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Daniel Starke Subject: [PATCH 5.16 158/164] tty: n_gsm: fix wrong tty control line for flow control Date: Mon, 28 Feb 2022 18:25:20 +0100 Message-Id: <20220228172414.025967453@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220228172359.567256961@linuxfoundation.org> References: <20220228172359.567256961@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: daniel.starke@siemens.com commit c19d93542a6081577e6da9bf5e887979c72e80c1 upstream. tty flow control is handled via gsmtty_throttle() and gsmtty_unthrottle(). Both functions propagate the outgoing hardware flow control state to the remote side via MSC (modem status command) frames. The local state is taken from the RTS (ready to send) flag of the tty. However, RTS gets mapped to DTR (data terminal ready), which is wrong. This patch corrects this by mapping RTS to RTS. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Cc: stable@vger.kernel.org Signed-off-by: Daniel Starke Link: https://lore.kernel.org/r/20220218073123.2121-5-daniel.starke@siemens.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/n_gsm.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -3246,9 +3246,9 @@ static void gsmtty_throttle(struct tty_s if (dlci->state == DLCI_CLOSED) return; if (C_CRTSCTS(tty)) - dlci->modem_tx &= ~TIOCM_DTR; + dlci->modem_tx &= ~TIOCM_RTS; dlci->throttled = true; - /* Send an MSC with DTR cleared */ + /* Send an MSC with RTS cleared */ gsmtty_modem_update(dlci, 0); } @@ -3258,9 +3258,9 @@ static void gsmtty_unthrottle(struct tty if (dlci->state == DLCI_CLOSED) return; if (C_CRTSCTS(tty)) - dlci->modem_tx |= TIOCM_DTR; + dlci->modem_tx |= TIOCM_RTS; dlci->throttled = false; - /* Send an MSC with DTR set */ + /* Send an MSC with RTS set */ gsmtty_modem_update(dlci, 0); }