From patchwork Thu Feb 2 14:59:33 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "D. Starke" X-Patchwork-Id: 650588 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 9A230C61DA4 for ; Thu, 2 Feb 2023 15:00:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232182AbjBBPA5 (ORCPT ); Thu, 2 Feb 2023 10:00:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40490 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229916AbjBBPA4 (ORCPT ); Thu, 2 Feb 2023 10:00:56 -0500 Received: from mta-64-227.siemens.flowmailer.net (mta-64-227.siemens.flowmailer.net [185.136.64.227]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B4A4F24103 for ; Thu, 2 Feb 2023 07:00:53 -0800 (PST) Received: by mta-64-227.siemens.flowmailer.net with ESMTPSA id 20230202150051505bf481a34e84b1ee for ; Thu, 02 Feb 2023 16:00:51 +0100 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; s=fm1; d=siemens.com; i=daniel.starke@siemens.com; h=Date:From:Subject:To:Message-ID:MIME-Version:Content-Type:Content-Transfer-Encoding:Cc:References:In-Reply-To; bh=CGxEhyAoxwEddJ0xl4OF2ojfXEmQZFbiyIt4XcYZYMI=; b=oFm7tsEbzNjln8ACwbYSnM8fp5u8CRuWKKLUxzh4QBJSiSe2NXcTPMrOAYNrMOFzYSSOXe sUVP86thOq5sefEzlqiL2VWEeT2g6n9SZXzRotnTvT5jn43+U3w7lzz0bJf9HwLO/k8Kj6pG /quUsM1DNz0abYmXxhdJlbTsB3LBU=; From: "D. Starke" To: linux-serial@vger.kernel.org, gregkh@linuxfoundation.org, jirislaby@kernel.org, ilpo.jarvinen@linux.intel.com Cc: linux-kernel@vger.kernel.org, Daniel Starke Subject: [PATCH v2 2/3] tty: n_gsm: add RING/CD control support Date: Thu, 2 Feb 2023 15:59:33 +0100 Message-Id: <20230202145934.22641-2-daniel.starke@siemens.com> In-Reply-To: <20230202145934.22641-1-daniel.starke@siemens.com> References: <20230202145934.22641-1-daniel.starke@siemens.com> MIME-Version: 1.0 X-Flowmailer-Platform: Siemens Feedback-ID: 519:519-314044:519-21489:flowmailer Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org From: Daniel Starke The status lines ring and carrier detect are used by the modem to signal incoming calls (RING) or an established connection (CD). This is implemented as physical lines on a standard RS232 connection. However, the muxer protocol encodes these status lines as modem bits IC and DV. These incoming lines are masked by tty driver (see tty_io.c) and cannot be set by a user application. Allow setting RING via TIOCM_OUT1 and CD via TIOCM_OUT2 to allow implementation of a modem or modem emulator. Signed-off-by: Daniel Starke --- drivers/tty/n_gsm.c | 5 +++++ 1 file changed, 5 insertions(+) v1 -> v2: No changes. diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index d068df1cf2fd..cf1ab7d619d9 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -546,6 +546,11 @@ static u8 gsm_encode_modem(const struct gsm_dlci *dlci) modembits |= MDM_IC; if (dlci->modem_tx & TIOCM_CD || dlci->gsm->initiator) modembits |= MDM_DV; + /* special mappings for passive side to operate as UE */ + if (dlci->modem_tx & TIOCM_OUT1) + modembits |= MDM_IC; + if (dlci->modem_tx & TIOCM_OUT2) + modembits |= MDM_DV; return modembits; }