From patchwork Thu Apr 30 16:04:14 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: 220192 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31834C47247 for ; Thu, 30 Apr 2020 16:06:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 08212208D5 for ; Thu, 30 Apr 2020 16:06:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588262819; bh=nFix0a/j/Cj5TviaDz5+T9+Ut0oC83oAgMWkoZOnEvQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=B0XHHHEKFwk+rGCcORzt3zj30zFtZzXpxDmjR4bWaR0Lys9JB1jEcYxKtsecp0L0h 7EjuWtVD8+iGUb/shdTIUrfqrIFqvsjdhXx/6m//5Khyq1tgi3Rgns+OwK2FWNwAhi UFfJyarLLqAEKWvBh50rQzqvYUpNhWTdPOSlyhhk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728489AbgD3QG6 (ORCPT ); Thu, 30 Apr 2020 12:06:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:50864 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726960AbgD3QEi (ORCPT ); Thu, 30 Apr 2020 12:04:38 -0400 Received: from mail.kernel.org (ip5f5ad5c5.dynamic.kabel-deutschland.de [95.90.213.197]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3A49624970; Thu, 30 Apr 2020 16:04:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588262676; bh=nFix0a/j/Cj5TviaDz5+T9+Ut0oC83oAgMWkoZOnEvQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IkzFj0pBnvQtFcGQpcY7mKuY7CwzkLdlE9w6FUv7aqrdOx4zaGMTkIpYV8ysll2T1 YWMwLz/uVefvLrz5q1HgKt9hKtsA6TpgTUSWhUnk7V6Ll+9UTUBJpAFWzWDgGHYEKr kSTOF+2o8uoSimJ5RQtZMq8CkGNGhZnKfh58O9FU= Received: from mchehab by mail.kernel.org with local (Exim 4.92.3) (envelope-from ) id 1jUBfu-00AxFc-Fq; Thu, 30 Apr 2020 18:04:34 +0200 From: Mauro Carvalho Chehab To: Linux Doc Mailing List Cc: Mauro Carvalho Chehab , linux-kernel@vger.kernel.org, Jonathan Corbet , "David S. Miller" , Jakub Kicinski , netdev@vger.kernel.org Subject: [PATCH 19/37] docs: networking: convert PLIP.txt to ReST Date: Thu, 30 Apr 2020 18:04:14 +0200 Message-Id: <3a25bd7bb5cda9f622d43584bd0d062034fa4fb6.1588261997.git.mchehab+huawei@kernel.org> X-Mailer: git-send-email 2.25.4 In-Reply-To: References: MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org - add SPDX header; - mark code blocks and literals as such; - adjust identation, whitespaces and blank lines where needed; - add to networking/index.rst. Signed-off-by: Mauro Carvalho Chehab --- Documentation/networking/index.rst | 1 + .../networking/{PLIP.txt => plip.rst} | 43 +++++++++++-------- drivers/net/plip/Kconfig | 2 +- 3 files changed, 27 insertions(+), 19 deletions(-) rename Documentation/networking/{PLIP.txt => plip.rst} (92%) diff --git a/Documentation/networking/index.rst b/Documentation/networking/index.rst index 696181a96e3c..18bb10239cad 100644 --- a/Documentation/networking/index.rst +++ b/Documentation/networking/index.rst @@ -92,6 +92,7 @@ Contents: packet_mmap phonet pktgen + plip .. only:: subproject and html diff --git a/Documentation/networking/PLIP.txt b/Documentation/networking/plip.rst similarity index 92% rename from Documentation/networking/PLIP.txt rename to Documentation/networking/plip.rst index ad7e3f7c3bbf..0eda745050ff 100644 --- a/Documentation/networking/PLIP.txt +++ b/Documentation/networking/plip.rst @@ -1,4 +1,8 @@ +.. SPDX-License-Identifier: GPL-2.0 + +================================================ PLIP: The Parallel Line Internet Protocol Device +================================================ Donald Becker (becker@super.org) I.D.A. Supercomputing Research Center, Bowie MD 20715 @@ -83,7 +87,7 @@ When the PLIP driver is used in IRQ mode, the timeout used for triggering a data transfer (the maximal time the PLIP driver would allow the other side before announcing a timeout, when trying to handshake a transfer of some data) is, by default, 500usec. As IRQ delivery is more or less immediate, -this timeout is quite sufficient. +this timeout is quite sufficient. When in IRQ-less mode, the PLIP driver polls the parallel port HZ times per second (where HZ is typically 100 on most platforms, and 1024 on an @@ -115,7 +119,7 @@ printer "null" cable to transfer data four bits at a time using data bit outputs connected to status bit inputs. The second data transfer method relies on both machines having -bi-directional parallel ports, rather than output-only ``printer'' +bi-directional parallel ports, rather than output-only ``printer`` ports. This allows byte-wide transfers and avoids reconstructing nibbles into bytes, leading to much faster transfers. @@ -132,7 +136,7 @@ bits with standard status register implementation. A cable that implements this protocol is available commercially as a "Null Printer" or "Turbo Laplink" cable. It can be constructed with -two DB-25 male connectors symmetrically connected as follows: +two DB-25 male connectors symmetrically connected as follows:: STROBE output 1* D0->ERROR 2 - 15 15 - 2 @@ -146,7 +150,8 @@ two DB-25 male connectors symmetrically connected as follows: SLCTIN 17 - 17 extra grounds are 18*,19*,20*,21*,22*,23*,24* GROUND 25 - 25 -* Do not connect these pins on either end + + * Do not connect these pins on either end If the cable you are using has a metallic shield it should be connected to the metallic DB-25 shell at one end only. @@ -155,14 +160,14 @@ Parallel Transfer Mode 1 ======================== The second data transfer method relies on both machines having -bi-directional parallel ports, rather than output-only ``printer'' +bi-directional parallel ports, rather than output-only ``printer`` ports. This allows byte-wide transfers, and avoids reconstructing nibbles into bytes. This cable should not be used on unidirectional -``printer'' (as opposed to ``parallel'') ports or when the machine +``printer`` (as opposed to ``parallel``) ports or when the machine isn't configured for PLIP, as it will result in output driver conflicts and the (unlikely) possibility of damage. -The cable for this transfer mode should be constructed as follows: +The cable for this transfer mode should be constructed as follows:: STROBE->BUSY 1 - 11 D0->D0 2 - 2 @@ -179,7 +184,8 @@ The cable for this transfer mode should be constructed as follows: GND->ERROR 18 - 15 extra grounds are 19*,20*,21*,22*,23*,24* GROUND 25 - 25 -* Do not connect these pins on either end + + * Do not connect these pins on either end Once again, if the cable you are using has a metallic shield it should be connected to the metallic DB-25 shell at one end only. @@ -188,7 +194,7 @@ PLIP Mode 0 transfer protocol ============================= The PLIP driver is compatible with the "Crynwr" parallel port transfer -standard in Mode 0. That standard specifies the following protocol: +standard in Mode 0. That standard specifies the following protocol:: send header nibble '0x8' count-low octet @@ -196,20 +202,21 @@ standard in Mode 0. That standard specifies the following protocol: ... data octets checksum octet -Each octet is sent as +Each octet is sent as:: + >4)&0x0F)> To start a transfer the transmitting machine outputs a nibble 0x08. That raises the ACK line, triggering an interrupt in the receiving machine. The receiving machine disables interrupts and raises its own ACK -line. +line. -Restated: +Restated:: -(OUT is bit 0-4, OUT.j is bit j from OUT. IN likewise) -Send_Byte: - OUT := low nibble, OUT.4 := 1 - WAIT FOR IN.4 = 1 - OUT := high nibble, OUT.4 := 0 - WAIT FOR IN.4 = 0 + (OUT is bit 0-4, OUT.j is bit j from OUT. IN likewise) + Send_Byte: + OUT := low nibble, OUT.4 := 1 + WAIT FOR IN.4 = 1 + OUT := high nibble, OUT.4 := 0 + WAIT FOR IN.4 = 0 diff --git a/drivers/net/plip/Kconfig b/drivers/net/plip/Kconfig index b41035be2d51..e03556d1d0c2 100644 --- a/drivers/net/plip/Kconfig +++ b/drivers/net/plip/Kconfig @@ -21,7 +21,7 @@ config PLIP bits at a time (mode 0) or with special PLIP cables, to be used on bidirectional parallel ports only, which can transmit 8 bits at a time (mode 1); you can find the wiring of these cables in - . The cables can be up to + . The cables can be up to 15m long. Mode 0 works also if one of the machines runs DOS/Windows and has some PLIP software installed, e.g. the Crynwr PLIP packet driver ()