From owner-freebsd-multimedia@FreeBSD.ORG Mon Apr 16 21:26:06 2007 Return-Path: X-Original-To: freebsd-multimedia@FreeBSD.org Delivered-To: freebsd-multimedia@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 9FA9016A403 for ; Mon, 16 Apr 2007 21:26:06 +0000 (UTC) (envelope-from jmg@hydrogen.funkthat.com) Received: from hydrogen.funkthat.com (gate.funkthat.com [69.17.45.168]) by mx1.freebsd.org (Postfix) with ESMTP id 6DAF713C43E for ; Mon, 16 Apr 2007 21:26:06 +0000 (UTC) (envelope-from jmg@hydrogen.funkthat.com) Received: from hydrogen.funkthat.com (wrectec0nrrg3wf4@localhost.funkthat.com [127.0.0.1]) by hydrogen.funkthat.com (8.13.6/8.13.3) with ESMTP id l3GLQ5dd019623; Mon, 16 Apr 2007 14:26:05 -0700 (PDT) (envelope-from jmg@hydrogen.funkthat.com) Received: (from jmg@localhost) by hydrogen.funkthat.com (8.13.6/8.13.3/Submit) id l3GLQ5Hl019622; Mon, 16 Apr 2007 14:26:05 -0700 (PDT) (envelope-from jmg) Date: Mon, 16 Apr 2007 14:26:05 -0700 From: John-Mark Gurney To: "Greg 'groggy' Lehey" Message-ID: <20070416212605.GV73385@funkthat.com> Mail-Followup-To: Greg 'groggy' Lehey , usleepless@gmail.com, freebsd-multimedia@freebsd.org References: <20070416055055.GC1593@wantadilla.lemis.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070416055055.GC1593@wantadilla.lemis.com> User-Agent: Mutt/1.4.2.1i X-Operating-System: FreeBSD 5.4-RELEASE-p6 i386 X-Files: The truth is out there X-URL: http://resnet.uoregon.edu/~gurney_j/ X-Resume: http://resnet.uoregon.edu/~gurney_j/resume.html Cc: freebsd-multimedia@FreeBSD.org Subject: Re: pvrxxx, linux code and modules X-BeenThere: freebsd-multimedia@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: John-Mark Gurney List-Id: Multimedia discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 16 Apr 2007 21:26:06 -0000 Greg 'groggy' Lehey wrote this message on Mon, Apr 16, 2007 at 15:20 +0930: > - I need to understand better how tuners work. I've been thinking of > writing a document on the subject, something that people could use > for help when writing drivers. If you know of anything, even > partial or badly laid out, please let me know. Just to reiterate, tuner code really should be located in userland.. it's not time sensitive, and can't corrupted state of the kernel.. As for tuners, most/all of them communicate through the i2c bus... The tuner is programed w/ the frequency to tune, and depending upon the range of frequence will turn on/off various transistors to change some of the analog curcuit behavior... My HDTV device drive does all the tuning from userland... It was a lot easier to get it working using userland than having to constantly load/unload kernel modules, and risk crashing the machine... -- John-Mark Gurney Voice: +1 415 225 5579 "All that I will do, has been done, All that I have, has not."