From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dalibor Kranjcic Subject: modem multiplexing mode? Date: 19 Aug 2003 11:51:32 +0200 Sender: linux-serial-owner@vger.kernel.org Message-ID: <1061286695.1312.172.camel@dalibork.ultra.si> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from naomi.triera.net ([213.161.0.25]:20144 "EHLO naomi.triera.net") by vger.kernel.org with ESMTP id S269639AbTHSJvg (ORCPT ); Tue, 19 Aug 2003 05:51:36 -0400 Received: from dalibork.ultra.si (cpe1-7-75.cable.triera.net [213.161.7.75]) by naomi.triera.net (Postfix) with ESMTP id D156C177A4 for ; Tue, 19 Aug 2003 11:52:42 +0200 (CEST) List-Id: linux-serial@vger.kernel.org To: linux-serial@vger.kernel.org Hi, Is there any way to send addtional traffic (AT commands) to serial port (/dev/ttyS1 (COM2) in my example) when ppp is atached to it, thus providing something as a modem multiplexing mode/protocol (Wavecom GPRS modem), since /dev/ttyS1 is locked by pppd and used by ppp modules. I tried to use /dev/ttyS12 as virtual port for COM2, which would allow sending of additional data flow to COM2 independently from the data flow which is already sent trough /dev/ttyS1 (ppp traffic). So, I expect write to /dev/ttyS12 to activate rs_interrupt_single method which does the actual write in serial driver. Once I'm in rs_interrupt_single method I would redirect the incoming user space data to TX lines for COM2. The write to /dev/ttyS12 fails with EIO Input/Output error, I suppose because there is no UART defined for this device and some initialization stuff doesn't go trough. Is there any way to have more (virtual) tty device files for the same COM thus allowing AT commands to be sent despite present ppp traffic. Is it possible to send AT commands when ppp traffic is running on serial port? Thanks for any advice... Dalibor Kranjcic.