From owner-freebsd-multimedia@FreeBSD.ORG Wed Apr 30 10:44:33 2003 Return-Path: Delivered-To: freebsd-multimedia@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 43E6437B401 for ; Wed, 30 Apr 2003 10:44:33 -0700 (PDT) Received: from arg1.demon.co.uk (arg1.demon.co.uk [62.49.12.213]) by mx1.FreeBSD.org (Postfix) with ESMTP id 7B87943F3F for ; Wed, 30 Apr 2003 10:44:30 -0700 (PDT) (envelope-from arg-bsd@arg1.demon.co.uk) Received: by arg1.demon.co.uk (Postfix, from userid 1002) id 63E4A9B02; Wed, 30 Apr 2003 18:44:29 +0100 (BST) Received: from localhost (localhost [127.0.0.1]) by arg1.demon.co.uk (Postfix) with ESMTP id 60FB75D03 for ; Wed, 30 Apr 2003 18:44:29 +0100 (BST) Date: Wed, 30 Apr 2003 18:44:29 +0100 (BST) From: Andrew Gordon X-X-Sender: To: In-Reply-To: <200304301259.39771.mistry.7@osu.edu> Message-ID: <20030430182544.E10214-100000@server.arg.sj.co.uk> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Subject: Re: Audio sampling from bt848-based cards X-BeenThere: freebsd-multimedia@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Multimedia discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 30 Apr 2003 17:44:33 -0000 On Wed, 30 Apr 2003, Anish Mistry wrote: > On Wednesday 30 April 2003 11:59 am, Steve O'Hara-Smith wrote: > > with trying to understand the pcm framework at the same time as trying to > > separate the linux bits from the btaudio bits - three unkowns were > > getting too much - then I got too busy with other things. I get the > > distinct impression it should be quite straightforward for someone > > practiced at porting linux audio drivers to BSD pcm. > > > Wouldn't there be an issue of GPL code vs. BSD license in porting the code? I > ask since my sound card only has linux GPL drivers and the chipset > manufactuer doesn't want to release the spec, but I'm hesitant to look at the > GPL code since then whatever I get from it wouldn't that have to be GPL'd and > then now be able to be included in the kernel? There's no great need to look at Linux drivers to implement a BT878 audio driver: the BT878/879 datasheet is on the web and describes the audio side reasonably well. In particular, the audio DMA engine is the same as the video DMA engine, so you'd be better off stealing from the FreeBSD bktr driver than the Linux driver for 90% of the code. http://www.conexant.com/products/prodparts.jsp?id=707 (you want the datasheet, errata and application note linked from that page)