From patchwork Thu Feb 6 15:17:29 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mauro Carvalho Chehab X-Patchwork-Id: 11368765 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 21D43109A for ; Thu, 6 Feb 2020 15:18:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E224421741 for ; Thu, 6 Feb 2020 15:18:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581002310; bh=XdTyZooBRMKtyKSrT4v/e8SPc1N3XdUEAP2haII5urU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=wzYKFUO4fQBsOdB6KpsRav3VqQAarHdPDSxBtnYib4oCR45Dhed2wICwamFMz5ZS2 TZp59kAay3dVTWSwO6xf3S9e40arNZew4xv+5TFIAIzriltpEBb4bJspx6DyLLRLjo znsk4Vc7VJEXMoALg66wBGtlakvC7u5xT8fkSKYs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727833AbgBFPS2 (ORCPT ); Thu, 6 Feb 2020 10:18:28 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:38146 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727600AbgBFPSA (ORCPT ); Thu, 6 Feb 2020 10:18:00 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Sender:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description; bh=TDw4+n6xFIkIZr6/PMan7IvWXuztzHBg7QOOp1nQd6U=; b=tyrOorZGg0l/BAcXz//a1S6VmB AHc1UDlvIBDN1MUiIG0StZ1YKBfgyBLYKBSOEfTQ6ForLgpKnFh+nxaacZwGL/Z94KB779y1I/UW0 XDMYScpzS1mJ5Uw4DIBg2WTuRNO1kUJCEJEucUFRSc8E3mQ6ko3N54wColDvdlMPi2SqVa3SBQv2S bjXhW2DOFuU74Z++DCsmssYt3hyw1HXowaS+1ErYB0/AuGfFFxRVHgQWAPfOgGUcquorhNmZQMWDA 7qjSWYVT9Ye9/AZD9Qo+U2xVFcP5I0+bjfJij+m6WvFS4ve35WzW0JtWB65hYrJa8lj0lufC/d2ZE 4AsiTcgA==; Received: from [179.95.15.160] (helo=bombadil.infradead.org) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1iziul-0005jP-Ib; Thu, 06 Feb 2020 15:18:00 +0000 Received: from mchehab by bombadil.infradead.org with local (Exim 4.92.3) (envelope-from ) id 1iziud-002oVJ-3l; Thu, 06 Feb 2020 16:17:51 +0100 From: Mauro Carvalho Chehab To: Linux Media Mailing List Cc: Mauro Carvalho Chehab , Mauro Carvalho Chehab , "David S. Miller" , Jakub Kicinski , Jonathan Corbet , netdev@vger.kernel.org, linux-doc@vger.kernel.org Subject: [PATCH 09/28] docs: networking: convert baycom.txt to ReST Date: Thu, 6 Feb 2020 16:17:29 +0100 Message-Id: <14095ed618a5e64460923da48236bfc6d8943e5a.1581002063.git.mchehab+huawei@kernel.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: References: MIME-Version: 1.0 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org - add SPDX header; - adjust titles and chapters, adding proper markups; - mark code blocks and literals as such; - mark tables as such; - adjust identation, whitespaces and blank lines; - add to networking/index.rst. Signed-off-by: Mauro Carvalho Chehab --- .../networking/{baycom.txt => baycom.rst} | 110 ++++++++++-------- Documentation/networking/index.rst | 1 + 2 files changed, 64 insertions(+), 47 deletions(-) rename Documentation/networking/{baycom.txt => baycom.rst} (58%) diff --git a/Documentation/networking/baycom.txt b/Documentation/networking/baycom.rst similarity index 58% rename from Documentation/networking/baycom.txt rename to Documentation/networking/baycom.rst index 688f18fd4467..fe2d010f0e86 100644 --- a/Documentation/networking/baycom.txt +++ b/Documentation/networking/baycom.rst @@ -1,26 +1,31 @@ - LINUX DRIVERS FOR BAYCOM MODEMS +.. SPDX-License-Identifier: GPL-2.0 - Thomas M. Sailer, HB9JNX/AE4WA, +=============================== +Linux Drivers for Baycom Modems +=============================== -!!NEW!! (04/98) The drivers for the baycom modems have been split into +Thomas M. Sailer, HB9JNX/AE4WA, + +The drivers for the baycom modems have been split into separate drivers as they did not share any code, and the driver and device names have changed. This document describes the Linux Kernel Drivers for simple Baycom style -amateur radio modems. +amateur radio modems. The following drivers are available: +==================================== baycom_ser_fdx: This driver supports the SER12 modems either full or half duplex. - Its baud rate may be changed via the `baud' module parameter, + Its baud rate may be changed via the ``baud`` module parameter, therefore it supports just about every bit bang modem on a serial port. Its devices are called bcsf0 through bcsf3. This is the recommended driver for SER12 type modems, however if you have a broken UART clone that does not have working - delta status bits, you may try baycom_ser_hdx. + delta status bits, you may try baycom_ser_hdx. -baycom_ser_hdx: +baycom_ser_hdx: This is an alternative driver for SER12 type modems. It only supports half duplex, and only 1200 baud. Its devices are called bcsh0 through bcsh3. Use this driver only if baycom_ser_fdx @@ -37,45 +42,48 @@ baycom_epp: The following modems are supported: -ser12: This is a very simple 1200 baud AFSK modem. The modem consists only - of a modulator/demodulator chip, usually a TI TCM3105. The computer - is responsible for regenerating the receiver bit clock, as well as - for handling the HDLC protocol. The modem connects to a serial port, - hence the name. Since the serial port is not used as an async serial - port, the kernel driver for serial ports cannot be used, and this - driver only supports standard serial hardware (8250, 16450, 16550) +======= ======================================================================== +ser12 This is a very simple 1200 baud AFSK modem. The modem consists only + of a modulator/demodulator chip, usually a TI TCM3105. The computer + is responsible for regenerating the receiver bit clock, as well as + for handling the HDLC protocol. The modem connects to a serial port, + hence the name. Since the serial port is not used as an async serial + port, the kernel driver for serial ports cannot be used, and this + driver only supports standard serial hardware (8250, 16450, 16550) -par96: This is a modem for 9600 baud FSK compatible to the G3RUH standard. - The modem does all the filtering and regenerates the receiver clock. - Data is transferred from and to the PC via a shift register. - The shift register is filled with 16 bits and an interrupt is signalled. - The PC then empties the shift register in a burst. This modem connects - to the parallel port, hence the name. The modem leaves the - implementation of the HDLC protocol and the scrambler polynomial to - the PC. +par96 This is a modem for 9600 baud FSK compatible to the G3RUH standard. + The modem does all the filtering and regenerates the receiver clock. + Data is transferred from and to the PC via a shift register. + The shift register is filled with 16 bits and an interrupt is signalled. + The PC then empties the shift register in a burst. This modem connects + to the parallel port, hence the name. The modem leaves the + implementation of the HDLC protocol and the scrambler polynomial to + the PC. -picpar: This is a redesign of the par96 modem by Henning Rech, DF9IC. The modem - is protocol compatible to par96, but uses only three low power ICs - and can therefore be fed from the parallel port and does not require - an additional power supply. Furthermore, it incorporates a carrier - detect circuitry. +picpar This is a redesign of the par96 modem by Henning Rech, DF9IC. The modem + is protocol compatible to par96, but uses only three low power ICs + and can therefore be fed from the parallel port and does not require + an additional power supply. Furthermore, it incorporates a carrier + detect circuitry. -EPP: This is a high-speed modem adaptor that connects to an enhanced parallel port. - Its target audience is users working over a high speed hub (76.8kbit/s). - -eppfpga: This is a redesign of the EPP adaptor. +EPP This is a high-speed modem adaptor that connects to an enhanced parallel + port. + Its target audience is users working over a high speed hub (76.8kbit/s). +eppfpga This is a redesign of the EPP adaptor. +======= ======================================================================== All of the above modems only support half duplex communications. However, the driver supports the KISS (see below) fullduplex command. It then simply starts to send as soon as there's a packet to transmit and does not care about DCD, i.e. it starts to send even if there's someone else on the channel. -This command is required by some implementations of the DAMA channel +This command is required by some implementations of the DAMA channel access protocol. The Interface of the drivers +============================ Unlike previous drivers, these drivers are no longer character devices, but they are now true kernel network interfaces. Installation is therefore @@ -88,20 +96,22 @@ me for WAMPES which allows attaching a kernel network interface directly. Configuring the driver +====================== Every time a driver is inserted into the kernel, it has to know which modems it should access at which ports. This can be done with the setbaycom utility. If you are only using one modem, you can also configure the driver from the insmod command line (or by means of an option line in -/etc/modprobe.d/*.conf). +``/etc/modprobe.d/*.conf``). + +Examples:: -Examples: modprobe baycom_ser_fdx mode="ser12*" iobase=0x3f8 irq=4 sethdlc -i bcsf0 -p mode "ser12*" io 0x3f8 irq 4 Both lines configure the first port to drive a ser12 modem at the first -serial port (COM1 under DOS). The * in the mode parameter instructs the driver to use -the software DCD algorithm (see below). +serial port (COM1 under DOS). The * in the mode parameter instructs the driver +to use the software DCD algorithm (see below):: insmod baycom_par mode="picpar" iobase=0x378 sethdlc -i bcp0 -p mode "picpar" io 0x378 @@ -115,29 +125,33 @@ Note that both utilities interpret the values slightly differently. Hardware DCD versus Software DCD +================================ To avoid collisions on the air, the driver must know when the channel is busy. This is the task of the DCD circuitry/software. The driver may either utilise a software DCD algorithm (options=1) or use a DCD signal from the hardware (options=0). -ser12: if software DCD is utilised, the radio's squelch should always be - open. It is highly recommended to use the software DCD algorithm, - as it is much faster than most hardware squelch circuitry. The - disadvantage is a slightly higher load on the system. +======= ================================================================= +ser12 if software DCD is utilised, the radio's squelch should always be + open. It is highly recommended to use the software DCD algorithm, + as it is much faster than most hardware squelch circuitry. The + disadvantage is a slightly higher load on the system. -par96: the software DCD algorithm for this type of modem is rather poor. - The modem simply does not provide enough information to implement - a reasonable DCD algorithm in software. Therefore, if your radio - feeds the DCD input of the PAR96 modem, the use of the hardware - DCD circuitry is recommended. +par96 the software DCD algorithm for this type of modem is rather poor. + The modem simply does not provide enough information to implement + a reasonable DCD algorithm in software. Therefore, if your radio + feeds the DCD input of the PAR96 modem, the use of the hardware + DCD circuitry is recommended. -picpar: the picpar modem features a builtin DCD hardware, which is highly - recommended. +picpar the picpar modem features a builtin DCD hardware, which is highly + recommended. +======= ================================================================= Compatibility with the rest of the Linux kernel +=============================================== The serial driver and the baycom serial drivers compete for the same hardware resources. Of course only one driver can access a given @@ -154,5 +168,7 @@ The parallel port drivers (baycom_par, baycom_epp) now use the parport subsystem to arbitrate the ports between different client drivers. vy 73s de + Tom Sailer, sailer@ife.ee.ethz.ch + hb9jnx @ hb9w.ampr.org diff --git a/Documentation/networking/index.rst b/Documentation/networking/index.rst index 1e0fc66739cc..250d29bf9efb 100644 --- a/Documentation/networking/index.rst +++ b/Documentation/networking/index.rst @@ -41,6 +41,7 @@ Contents: arcnet atm ax25 + baycom .. only:: subproject and html