Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756748AbYC1MzD (ORCPT ); Fri, 28 Mar 2008 08:55:03 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754980AbYC1Mww (ORCPT ); Fri, 28 Mar 2008 08:52:52 -0400 Received: from SpacedOut.fries.net ([67.64.210.234]:56332 "EHLO SpacedOut.fries.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756382AbYC1Mwu (ORCPT ); Fri, 28 Mar 2008 08:52:50 -0400 Date: Fri, 28 Mar 2008 07:25:15 -0500 From: David Fries To: linux-kernel@vger.kernel.org Cc: Evgeniy Polyakov Subject: [PATCH 9/35] W1: create documentation for the w1_therm slave device Message-ID: <20080328122515.GJ3613@spacedout.fries.net> References: <200803272343.m2RNhDac017650@SpacedOut.fries.net> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="SBT+cnFS/G3NVgv4" Content-Disposition: inline In-Reply-To: <200803272343.m2RNhDac017650@SpacedOut.fries.net> User-Agent: Mutt/1.5.4i X-Greylist: Sender is SPF-compliant, not delayed by milter-greylist-3.0 (SpacedOut.fries.net [127.0.0.1]); Fri, 28 Mar 2008 07:25:15 -0500 (CDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3469 Lines: 110 --SBT+cnFS/G3NVgv4 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable New directory for temperature sensor documentation. Documentation/w1/00-INDEX 1.2 Added new subdirectory slaves Documentation/w1/slaves/00-INDEX 1.1 1.2 Added index and w1_therm entry. Documentation/w1/slaves/w1_therm 1.1 1.2 Initial entry for the temperature sensor. Signed-off-by: David Fries --- Documentation/w1/00-INDEX | 2 ++ Documentation/w1/slaves/00-INDEX | 4 ++++ Documentation/w1/slaves/w1_therm | 35 +++++++++++++++++++++++++++++++++++ 3 files changed, 41 insertions(+), 0 deletions(-) diff --git a/Documentation/w1/00-INDEX b/Documentation/w1/00-INDEX index 5270cf4..cb49802 100644 --- a/Documentation/w1/00-INDEX +++ b/Documentation/w1/00-INDEX @@ -1,5 +1,7 @@ 00-INDEX - This file +slaves/ + - Drivers that provide support for specific family codes. masters/ - Individual chips providing 1-wire busses. w1.generic diff --git a/Documentation/w1/slaves/00-INDEX b/Documentation/w1/slaves/00-= INDEX new file mode 100644 index 0000000..f8101d6 --- /dev/null +++ b/Documentation/w1/slaves/00-INDEX @@ -0,0 +1,4 @@ +00-INDEX + - This file +w1_therm + - The Maxim/Dallas Semiconductor ds18*20 temperature sensor. diff --git a/Documentation/w1/slaves/w1_therm b/Documentation/w1/slaves/w1_= therm new file mode 100644 index 0000000..7b045ae --- /dev/null +++ b/Documentation/w1/slaves/w1_therm @@ -0,0 +1,35 @@ +Kernel driver w1_therm +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D + +Supported chips: + * Maxim ds18*20 based temperature sensors. + +Author: Evgeniy Polyakov + + +Description +----------- + +w1_therm provides basic temperature conversion for ds18*20 devices. +supported family codes: +W1_THERM_DS18S20 0x10 +W1_THERM_DS1822 0x22 +W1_THERM_DS18B20 0x28 +Support is provided through the sysfs w1_slave file. Each open and +read sequence will initiate a temperature conversion then provide two +lines of ASCII output. The first line contains the nine hex bytes +read along with a calculated crc value and YES or NO if it matched. +If the crc matched the returned values are retained. The second line +displays the retained values along with a temperature in millidegrees +Centigrade after t=3D. + +w1_therm selects the current slave device for temperature conversion +and provides a strong pullup if the master devices supports one and +delays 750ms for the conversion. + +Parasite powered devices are limited to one slave performing a +temperature conversion at a time. If none of the devices are parasite +powered it would be possible to convert all the devices at the same +time and then go back to read individual sensors. That isn't +currently supported. The driver also doesn't support reduced +precision (which would also reduce the conversion time). --=20 1.4.4.4 --SBT+cnFS/G3NVgv4 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.1 (GNU/Linux) iD8DBQFH7OOrAI852cse6PARAmxUAKDK3NbiTJ26qvz/h7BmapMPotkYfgCfeuca 9Be22n7AgAXCqoun3DsR2es= =M8JJ -----END PGP SIGNATURE----- --SBT+cnFS/G3NVgv4-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/